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kc3-lang/libxml2/xmlregexp.c
Nick Wellnhofer
- xmlregexp.c
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/* * regexp.c: generic and extensible Regular Expression engine * * Basically designed with the purpose of compiling regexps for * the variety of validation/schemas mechanisms now available in * XML related specifications these include: * - XML-1.0 DTD validation * - XML Schemas structure part 1 * - XML Schemas Datatypes part 2 especially Appendix F * - RELAX-NG/TREX i.e. the counter proposal * * See Copyright for the status of this software. * * Daniel Veillard <veillard@redhat.com> */ #define IN_LIBXML #include "libxml.h" #ifdef LIBXML_REGEXP_ENABLED #include <stdio.h> #include <string.h> #include <limits.h> #include <libxml/tree.h> #include <libxml/parserInternals.h> #include <libxml/xmlregexp.h> #include <libxml/xmlautomata.h> #include <libxml/xmlunicode.h> #include "private/error.h" #include "private/regexp.h" #ifndef SIZE_MAX #define SIZE_MAX ((size_t) -1) #endif #define MAX_PUSH 10000000 #ifdef ERROR #undef ERROR #endif #define ERROR(str) \ ctxt->error = XML_REGEXP_COMPILE_ERROR; \ xmlRegexpErrCompile(ctxt, str); #define NEXT ctxt->cur++ #define CUR (*(ctxt->cur)) #define NXT(index) (ctxt->cur[index]) #define CUR_SCHAR(s, l) xmlStringCurrentChar(NULL, s, &l) #define NEXTL(l) ctxt->cur += l; #define XML_REG_STRING_SEPARATOR '|' /* * Need PREV to check on a '-' within a Character Group. May only be used * when it's guaranteed that cur is not at the beginning of ctxt->string! */ #define PREV (ctxt->cur[-1]) /** * TODO: * * macro to flag unimplemented blocks */ #define TODO \ xmlGenericError(xmlGenericErrorContext, \ "Unimplemented block at %s:%d\n", \ __FILE__, __LINE__); /************************************************************************ * * * Datatypes and structures * * * ************************************************************************/ /* * Note: the order of the enums below is significant, do not shuffle */ typedef enum { XML_REGEXP_EPSILON = 1, XML_REGEXP_CHARVAL, XML_REGEXP_RANGES, XML_REGEXP_SUBREG, /* used for () sub regexps */ XML_REGEXP_STRING, XML_REGEXP_ANYCHAR, /* . */ XML_REGEXP_ANYSPACE, /* \s */ XML_REGEXP_NOTSPACE, /* \S */ XML_REGEXP_INITNAME, /* \l */ XML_REGEXP_NOTINITNAME, /* \L */ XML_REGEXP_NAMECHAR, /* \c */ XML_REGEXP_NOTNAMECHAR, /* \C */ XML_REGEXP_DECIMAL, /* \d */ XML_REGEXP_NOTDECIMAL, /* \D */ XML_REGEXP_REALCHAR, /* \w */ XML_REGEXP_NOTREALCHAR, /* \W */ XML_REGEXP_LETTER = 100, XML_REGEXP_LETTER_UPPERCASE, XML_REGEXP_LETTER_LOWERCASE, XML_REGEXP_LETTER_TITLECASE, XML_REGEXP_LETTER_MODIFIER, XML_REGEXP_LETTER_OTHERS, XML_REGEXP_MARK, XML_REGEXP_MARK_NONSPACING, XML_REGEXP_MARK_SPACECOMBINING, XML_REGEXP_MARK_ENCLOSING, XML_REGEXP_NUMBER, XML_REGEXP_NUMBER_DECIMAL, XML_REGEXP_NUMBER_LETTER, XML_REGEXP_NUMBER_OTHERS, XML_REGEXP_PUNCT, XML_REGEXP_PUNCT_CONNECTOR, XML_REGEXP_PUNCT_DASH, XML_REGEXP_PUNCT_OPEN, XML_REGEXP_PUNCT_CLOSE, XML_REGEXP_PUNCT_INITQUOTE, XML_REGEXP_PUNCT_FINQUOTE, XML_REGEXP_PUNCT_OTHERS, XML_REGEXP_SEPAR, XML_REGEXP_SEPAR_SPACE, XML_REGEXP_SEPAR_LINE, XML_REGEXP_SEPAR_PARA, XML_REGEXP_SYMBOL, XML_REGEXP_SYMBOL_MATH, XML_REGEXP_SYMBOL_CURRENCY, XML_REGEXP_SYMBOL_MODIFIER, XML_REGEXP_SYMBOL_OTHERS, XML_REGEXP_OTHER, XML_REGEXP_OTHER_CONTROL, XML_REGEXP_OTHER_FORMAT, XML_REGEXP_OTHER_PRIVATE, XML_REGEXP_OTHER_NA, XML_REGEXP_BLOCK_NAME } xmlRegAtomType; typedef enum { XML_REGEXP_QUANT_EPSILON = 1, XML_REGEXP_QUANT_ONCE, XML_REGEXP_QUANT_OPT, XML_REGEXP_QUANT_MULT, XML_REGEXP_QUANT_PLUS, XML_REGEXP_QUANT_ONCEONLY, XML_REGEXP_QUANT_ALL, XML_REGEXP_QUANT_RANGE } xmlRegQuantType; typedef enum { XML_REGEXP_START_STATE = 1, XML_REGEXP_FINAL_STATE, XML_REGEXP_TRANS_STATE, XML_REGEXP_SINK_STATE, XML_REGEXP_UNREACH_STATE } xmlRegStateType; typedef enum { XML_REGEXP_MARK_NORMAL = 0, XML_REGEXP_MARK_START, XML_REGEXP_MARK_VISITED } xmlRegMarkedType; typedef struct _xmlRegRange xmlRegRange; typedef xmlRegRange *xmlRegRangePtr; struct _xmlRegRange { int neg; /* 0 normal, 1 not, 2 exclude */ xmlRegAtomType type; int start; int end; xmlChar *blockName; }; typedef struct _xmlRegAtom xmlRegAtom; typedef xmlRegAtom *xmlRegAtomPtr; typedef struct _xmlAutomataState xmlRegState; typedef xmlRegState *xmlRegStatePtr; struct _xmlRegAtom { int no; xmlRegAtomType type; xmlRegQuantType quant; int min; int max; void *valuep; void *valuep2; int neg; int codepoint; xmlRegStatePtr start; xmlRegStatePtr start0; xmlRegStatePtr stop; int maxRanges; int nbRanges; xmlRegRangePtr *ranges; void *data; }; typedef struct _xmlRegCounter xmlRegCounter; typedef xmlRegCounter *xmlRegCounterPtr; struct _xmlRegCounter { int min; int max; }; typedef struct _xmlRegTrans xmlRegTrans; typedef xmlRegTrans *xmlRegTransPtr; struct _xmlRegTrans { xmlRegAtomPtr atom; int to; int counter; int count; int nd; }; struct _xmlAutomataState { xmlRegStateType type; xmlRegMarkedType mark; xmlRegMarkedType markd; xmlRegMarkedType reached; int no; int maxTrans; int nbTrans; xmlRegTrans *trans; /* knowing states pointing to us can speed things up */ int maxTransTo; int nbTransTo; int *transTo; }; typedef struct _xmlAutomata xmlRegParserCtxt; typedef xmlRegParserCtxt *xmlRegParserCtxtPtr; #define AM_AUTOMATA_RNG 1 struct _xmlAutomata { xmlChar *string; xmlChar *cur; int error; int neg; xmlRegStatePtr start; xmlRegStatePtr end; xmlRegStatePtr state; xmlRegAtomPtr atom; int maxAtoms; int nbAtoms; xmlRegAtomPtr *atoms; int maxStates; int nbStates; xmlRegStatePtr *states; int maxCounters; int nbCounters; xmlRegCounter *counters; int determinist; int negs; int flags; int depth; }; struct _xmlRegexp { xmlChar *string; int nbStates; xmlRegStatePtr *states; int nbAtoms; xmlRegAtomPtr *atoms; int nbCounters; xmlRegCounter *counters; int determinist; int flags; /* * That's the compact form for determinists automatas */ int nbstates; int *compact; void **transdata; int nbstrings; xmlChar **stringMap; }; typedef struct _xmlRegExecRollback xmlRegExecRollback; typedef xmlRegExecRollback *xmlRegExecRollbackPtr; struct _xmlRegExecRollback { xmlRegStatePtr state;/* the current state */ int index; /* the index in the input stack */ int nextbranch; /* the next transition to explore in that state */ int *counts; /* save the automata state if it has some */ }; typedef struct _xmlRegInputToken xmlRegInputToken; typedef xmlRegInputToken *xmlRegInputTokenPtr; struct _xmlRegInputToken { xmlChar *value; void *data; }; struct _xmlRegExecCtxt { int status; /* execution status != 0 indicate an error */ int determinist; /* did we find an indeterministic behaviour */ xmlRegexpPtr comp; /* the compiled regexp */ xmlRegExecCallbacks callback; void *data; xmlRegStatePtr state;/* the current state */ int transno; /* the current transition on that state */ int transcount; /* the number of chars in char counted transitions */ /* * A stack of rollback states */ int maxRollbacks; int nbRollbacks; xmlRegExecRollback *rollbacks; /* * The state of the automata if any */ int *counts; /* * The input stack */ int inputStackMax; int inputStackNr; int index; int *charStack; const xmlChar *inputString; /* when operating on characters */ xmlRegInputTokenPtr inputStack;/* when operating on strings */ /* * error handling */ int errStateNo; /* the error state number */ xmlRegStatePtr errState; /* the error state */ xmlChar *errString; /* the string raising the error */ int *errCounts; /* counters at the error state */ int nbPush; }; #define REGEXP_ALL_COUNTER 0x123456 #define REGEXP_ALL_LAX_COUNTER 0x123457 static void xmlFAParseRegExp(xmlRegParserCtxtPtr ctxt, int top); static void xmlRegFreeState(xmlRegStatePtr state); static void xmlRegFreeAtom(xmlRegAtomPtr atom); static int xmlRegStrEqualWildcard(const xmlChar *expStr, const xmlChar *valStr); static int xmlRegCheckCharacter(xmlRegAtomPtr atom, int codepoint); static int xmlRegCheckCharacterRange(xmlRegAtomType type, int codepoint, int neg, int start, int end, const xmlChar *blockName); /************************************************************************ * * * Regexp memory error handler * * * ************************************************************************/ /** * xmlRegexpErrMemory: * @extra: extra information * * Handle an out of memory condition */ static void xmlRegexpErrMemory(xmlRegParserCtxtPtr ctxt, const char *extra) { const char *regexp = NULL; if (ctxt != NULL) { regexp = (const char *) ctxt->string; ctxt->error = XML_ERR_NO_MEMORY; } __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_REGEXP, XML_ERR_NO_MEMORY, XML_ERR_FATAL, NULL, 0, extra, regexp, NULL, 0, 0, "Memory allocation failed : %s\n", extra); } /** * xmlRegexpErrCompile: * @extra: extra information * * Handle a compilation failure */ static void xmlRegexpErrCompile(xmlRegParserCtxtPtr ctxt, const char *extra) { const char *regexp = NULL; int idx = 0; if (ctxt != NULL) { regexp = (const char *) ctxt->string; idx = ctxt->cur - ctxt->string; ctxt->error = XML_REGEXP_COMPILE_ERROR; } __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_REGEXP, XML_REGEXP_COMPILE_ERROR, XML_ERR_FATAL, NULL, 0, extra, regexp, NULL, idx, 0, "failed to compile: %s\n", extra); } /************************************************************************ * * * Allocation/Deallocation * * * ************************************************************************/ static int xmlFAComputesDeterminism(xmlRegParserCtxtPtr ctxt); /** * xmlRegCalloc2: * @dim1: size of first dimension * @dim2: size of second dimension * @elemSize: size of element * * Allocate a two-dimensional array and set all elements to zero. * * Returns the new array or NULL in case of error. */ static void* xmlRegCalloc2(size_t dim1, size_t dim2, size_t elemSize) { size_t totalSize; void *ret; /* Check for overflow */ if ((dim2 == 0) || (elemSize == 0) || (dim1 > SIZE_MAX / dim2 / elemSize)) return (NULL); totalSize = dim1 * dim2 * elemSize; ret = xmlMalloc(totalSize); if (ret != NULL) memset(ret, 0, totalSize); return (ret); } /** * xmlRegEpxFromParse: * @ctxt: the parser context used to build it * * Allocate a new regexp and fill it with the result from the parser * * Returns the new regexp or NULL in case of error */ static xmlRegexpPtr xmlRegEpxFromParse(xmlRegParserCtxtPtr ctxt) { xmlRegexpPtr ret; ret = (xmlRegexpPtr) xmlMalloc(sizeof(xmlRegexp)); if (ret == NULL) { xmlRegexpErrMemory(ctxt, "compiling regexp"); return(NULL); } memset(ret, 0, sizeof(xmlRegexp)); ret->string = ctxt->string; ret->nbStates = ctxt->nbStates; ret->states = ctxt->states; ret->nbAtoms = ctxt->nbAtoms; ret->atoms = ctxt->atoms; ret->nbCounters = ctxt->nbCounters; ret->counters = ctxt->counters; ret->determinist = ctxt->determinist; ret->flags = ctxt->flags; if (ret->determinist == -1) { xmlRegexpIsDeterminist(ret); } if ((ret->determinist != 0) && (ret->nbCounters == 0) && (ctxt->negs == 0) && (ret->atoms != NULL) && (ret->atoms[0] != NULL) && (ret->atoms[0]->type == XML_REGEXP_STRING)) { int i, j, nbstates = 0, nbatoms = 0; int *stateRemap; int *stringRemap; int *transitions; void **transdata; xmlChar **stringMap; xmlChar *value; /* * Switch to a compact representation * 1/ counting the effective number of states left * 2/ counting the unique number of atoms, and check that * they are all of the string type * 3/ build a table state x atom for the transitions */ stateRemap = xmlMalloc(ret->nbStates * sizeof(int)); if (stateRemap == NULL) { xmlRegexpErrMemory(ctxt, "compiling regexp"); xmlFree(ret); return(NULL); } for (i = 0;i < ret->nbStates;i++) { if (ret->states[i] != NULL) { stateRemap[i] = nbstates; nbstates++; } else { stateRemap[i] = -1; } } stringMap = xmlMalloc(ret->nbAtoms * sizeof(char *)); if (stringMap == NULL) { xmlRegexpErrMemory(ctxt, "compiling regexp"); xmlFree(stateRemap); xmlFree(ret); return(NULL); } stringRemap = xmlMalloc(ret->nbAtoms * sizeof(int)); if (stringRemap == NULL) { xmlRegexpErrMemory(ctxt, "compiling regexp"); xmlFree(stringMap); xmlFree(stateRemap); xmlFree(ret); return(NULL); } for (i = 0;i < ret->nbAtoms;i++) { if ((ret->atoms[i]->type == XML_REGEXP_STRING) && (ret->atoms[i]->quant == XML_REGEXP_QUANT_ONCE)) { value = ret->atoms[i]->valuep; for (j = 0;j < nbatoms;j++) { if (xmlStrEqual(stringMap[j], value)) { stringRemap[i] = j; break; } } if (j >= nbatoms) { stringRemap[i] = nbatoms; stringMap[nbatoms] = xmlStrdup(value); if (stringMap[nbatoms] == NULL) { for (i = 0;i < nbatoms;i++) xmlFree(stringMap[i]); xmlFree(stringRemap); xmlFree(stringMap); xmlFree(stateRemap); xmlFree(ret); return(NULL); } nbatoms++; } } else { xmlFree(stateRemap); xmlFree(stringRemap); for (i = 0;i < nbatoms;i++) xmlFree(stringMap[i]); xmlFree(stringMap); xmlFree(ret); return(NULL); } } transitions = (int *) xmlRegCalloc2(nbstates + 1, nbatoms + 1, sizeof(int)); if (transitions == NULL) { xmlFree(stateRemap); xmlFree(stringRemap); for (i = 0;i < nbatoms;i++) xmlFree(stringMap[i]); xmlFree(stringMap); xmlFree(ret); return(NULL); } /* * Allocate the transition table. The first entry for each * state corresponds to the state type. */ transdata = NULL; for (i = 0;i < ret->nbStates;i++) { int stateno, atomno, targetno, prev; xmlRegStatePtr state; xmlRegTransPtr trans; stateno = stateRemap[i]; if (stateno == -1) continue; state = ret->states[i]; transitions[stateno * (nbatoms + 1)] = state->type; for (j = 0;j < state->nbTrans;j++) { trans = &(state->trans[j]); if ((trans->to < 0) || (trans->atom == NULL)) continue; atomno = stringRemap[trans->atom->no]; if ((trans->atom->data != NULL) && (transdata == NULL)) { transdata = (void **) xmlRegCalloc2(nbstates, nbatoms, sizeof(void *)); if (transdata == NULL) { xmlRegexpErrMemory(ctxt, "compiling regexp"); break; } } targetno = stateRemap[trans->to]; /* * if the same atom can generate transitions to 2 different * states then it means the automata is not deterministic and * the compact form can't be used ! */ prev = transitions[stateno * (nbatoms + 1) + atomno + 1]; if (prev != 0) { if (prev != targetno + 1) { ret->determinist = 0; if (transdata != NULL) xmlFree(transdata); xmlFree(transitions); xmlFree(stateRemap); xmlFree(stringRemap); for (i = 0;i < nbatoms;i++) xmlFree(stringMap[i]); xmlFree(stringMap); goto not_determ; } } else { #if 0 printf("State %d trans %d: atom %d to %d : %d to %d\n", i, j, trans->atom->no, trans->to, atomno, targetno); #endif transitions[stateno * (nbatoms + 1) + atomno + 1] = targetno + 1; /* to avoid 0 */ if (transdata != NULL) transdata[stateno * nbatoms + atomno] = trans->atom->data; } } } ret->determinist = 1; /* * Cleanup of the old data */ if (ret->states != NULL) { for (i = 0;i < ret->nbStates;i++) xmlRegFreeState(ret->states[i]); xmlFree(ret->states); } ret->states = NULL; ret->nbStates = 0; if (ret->atoms != NULL) { for (i = 0;i < ret->nbAtoms;i++) xmlRegFreeAtom(ret->atoms[i]); xmlFree(ret->atoms); } ret->atoms = NULL; ret->nbAtoms = 0; ret->compact = transitions; ret->transdata = transdata; ret->stringMap = stringMap; ret->nbstrings = nbatoms; ret->nbstates = nbstates; xmlFree(stateRemap); xmlFree(stringRemap); } not_determ: ctxt->string = NULL; ctxt->nbStates = 0; ctxt->states = NULL; ctxt->nbAtoms = 0; ctxt->atoms = NULL; ctxt->nbCounters = 0; ctxt->counters = NULL; return(ret); } /** * xmlRegNewParserCtxt: * @string: the string to parse * * Allocate a new regexp parser context * * Returns the new context or NULL in case of error */ static xmlRegParserCtxtPtr xmlRegNewParserCtxt(const xmlChar *string) { xmlRegParserCtxtPtr ret; ret = (xmlRegParserCtxtPtr) xmlMalloc(sizeof(xmlRegParserCtxt)); if (ret == NULL) return(NULL); memset(ret, 0, sizeof(xmlRegParserCtxt)); if (string != NULL) ret->string = xmlStrdup(string); ret->cur = ret->string; ret->neg = 0; ret->negs = 0; ret->error = 0; ret->determinist = -1; return(ret); } /** * xmlRegNewRange: * @ctxt: the regexp parser context * @neg: is that negative * @type: the type of range * @start: the start codepoint * @end: the end codepoint * * Allocate a new regexp range * * Returns the new range or NULL in case of error */ static xmlRegRangePtr xmlRegNewRange(xmlRegParserCtxtPtr ctxt, int neg, xmlRegAtomType type, int start, int end) { xmlRegRangePtr ret; ret = (xmlRegRangePtr) xmlMalloc(sizeof(xmlRegRange)); if (ret == NULL) { xmlRegexpErrMemory(ctxt, "allocating range"); return(NULL); } ret->neg = neg; ret->type = type; ret->start = start; ret->end = end; return(ret); } /** * xmlRegFreeRange: * @range: the regexp range * * Free a regexp range */ static void xmlRegFreeRange(xmlRegRangePtr range) { if (range == NULL) return; if (range->blockName != NULL) xmlFree(range->blockName); xmlFree(range); } /** * xmlRegCopyRange: * @range: the regexp range * * Copy a regexp range * * Returns the new copy or NULL in case of error. */ static xmlRegRangePtr xmlRegCopyRange(xmlRegParserCtxtPtr ctxt, xmlRegRangePtr range) { xmlRegRangePtr ret; if (range == NULL) return(NULL); ret = xmlRegNewRange(ctxt, range->neg, range->type, range->start, range->end); if (ret == NULL) return(NULL); if (range->blockName != NULL) { ret->blockName = xmlStrdup(range->blockName); if (ret->blockName == NULL) { xmlRegexpErrMemory(ctxt, "allocating range"); xmlRegFreeRange(ret); return(NULL); } } return(ret); } /** * xmlRegNewAtom: * @ctxt: the regexp parser context * @type: the type of atom * * Allocate a new atom * * Returns the new atom or NULL in case of error */ static xmlRegAtomPtr xmlRegNewAtom(xmlRegParserCtxtPtr ctxt, xmlRegAtomType type) { xmlRegAtomPtr ret; ret = (xmlRegAtomPtr) xmlMalloc(sizeof(xmlRegAtom)); if (ret == NULL) { xmlRegexpErrMemory(ctxt, "allocating atom"); return(NULL); } memset(ret, 0, sizeof(xmlRegAtom)); ret->type = type; ret->quant = XML_REGEXP_QUANT_ONCE; ret->min = 0; ret->max = 0; return(ret); } /** * xmlRegFreeAtom: * @atom: the regexp atom * * Free a regexp atom */ static void xmlRegFreeAtom(xmlRegAtomPtr atom) { int i; if (atom == NULL) return; for (i = 0;i < atom->nbRanges;i++) xmlRegFreeRange(atom->ranges[i]); if (atom->ranges != NULL) xmlFree(atom->ranges); if ((atom->type == XML_REGEXP_STRING) && (atom->valuep != NULL)) xmlFree(atom->valuep); if ((atom->type == XML_REGEXP_STRING) && (atom->valuep2 != NULL)) xmlFree(atom->valuep2); if ((atom->type == XML_REGEXP_BLOCK_NAME) && (atom->valuep != NULL)) xmlFree(atom->valuep); xmlFree(atom); } /** * xmlRegCopyAtom: * @ctxt: the regexp parser context * @atom: the original atom * * Allocate a new regexp range * * Returns the new atom or NULL in case of error */ static xmlRegAtomPtr xmlRegCopyAtom(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom) { xmlRegAtomPtr ret; ret = (xmlRegAtomPtr) xmlMalloc(sizeof(xmlRegAtom)); if (ret == NULL) { xmlRegexpErrMemory(ctxt, "copying atom"); return(NULL); } memset(ret, 0, sizeof(xmlRegAtom)); ret->type = atom->type; ret->quant = atom->quant; ret->min = atom->min; ret->max = atom->max; if (atom->nbRanges > 0) { int i; ret->ranges = (xmlRegRangePtr *) xmlMalloc(sizeof(xmlRegRangePtr) * atom->nbRanges); if (ret->ranges == NULL) { xmlRegexpErrMemory(ctxt, "copying atom"); goto error; } for (i = 0;i < atom->nbRanges;i++) { ret->ranges[i] = xmlRegCopyRange(ctxt, atom->ranges[i]); if (ret->ranges[i] == NULL) goto error; ret->nbRanges = i + 1; } } return(ret); error: xmlRegFreeAtom(ret); return(NULL); } static xmlRegStatePtr xmlRegNewState(xmlRegParserCtxtPtr ctxt) { xmlRegStatePtr ret; ret = (xmlRegStatePtr) xmlMalloc(sizeof(xmlRegState)); if (ret == NULL) { xmlRegexpErrMemory(ctxt, "allocating state"); return(NULL); } memset(ret, 0, sizeof(xmlRegState)); ret->type = XML_REGEXP_TRANS_STATE; ret->mark = XML_REGEXP_MARK_NORMAL; return(ret); } /** * xmlRegFreeState: * @state: the regexp state * * Free a regexp state */ static void xmlRegFreeState(xmlRegStatePtr state) { if (state == NULL) return; if (state->trans != NULL) xmlFree(state->trans); if (state->transTo != NULL) xmlFree(state->transTo); xmlFree(state); } /** * xmlRegFreeParserCtxt: * @ctxt: the regexp parser context * * Free a regexp parser context */ static void xmlRegFreeParserCtxt(xmlRegParserCtxtPtr ctxt) { int i; if (ctxt == NULL) return; if (ctxt->string != NULL) xmlFree(ctxt->string); if (ctxt->states != NULL) { for (i = 0;i < ctxt->nbStates;i++) xmlRegFreeState(ctxt->states[i]); xmlFree(ctxt->states); } if (ctxt->atoms != NULL) { for (i = 0;i < ctxt->nbAtoms;i++) xmlRegFreeAtom(ctxt->atoms[i]); xmlFree(ctxt->atoms); } if (ctxt->counters != NULL) xmlFree(ctxt->counters); xmlFree(ctxt); } /************************************************************************ * * * Display of Data structures * * * ************************************************************************/ static void xmlRegPrintAtomType(FILE *output, xmlRegAtomType type) { switch (type) { case XML_REGEXP_EPSILON: fprintf(output, "epsilon "); break; case XML_REGEXP_CHARVAL: fprintf(output, "charval "); break; case XML_REGEXP_RANGES: fprintf(output, "ranges "); break; case XML_REGEXP_SUBREG: fprintf(output, "subexpr "); break; case XML_REGEXP_STRING: fprintf(output, "string "); break; case XML_REGEXP_ANYCHAR: fprintf(output, "anychar "); break; case XML_REGEXP_ANYSPACE: fprintf(output, "anyspace "); break; case XML_REGEXP_NOTSPACE: fprintf(output, "notspace "); break; case XML_REGEXP_INITNAME: fprintf(output, "initname "); break; case XML_REGEXP_NOTINITNAME: fprintf(output, "notinitname "); break; case XML_REGEXP_NAMECHAR: fprintf(output, "namechar "); break; case XML_REGEXP_NOTNAMECHAR: fprintf(output, "notnamechar "); break; case XML_REGEXP_DECIMAL: fprintf(output, "decimal "); break; case XML_REGEXP_NOTDECIMAL: fprintf(output, "notdecimal "); break; case XML_REGEXP_REALCHAR: fprintf(output, "realchar "); break; case XML_REGEXP_NOTREALCHAR: fprintf(output, "notrealchar "); break; case XML_REGEXP_LETTER: fprintf(output, "LETTER "); break; case XML_REGEXP_LETTER_UPPERCASE: fprintf(output, "LETTER_UPPERCASE "); break; case XML_REGEXP_LETTER_LOWERCASE: fprintf(output, "LETTER_LOWERCASE "); break; case XML_REGEXP_LETTER_TITLECASE: fprintf(output, "LETTER_TITLECASE "); break; case XML_REGEXP_LETTER_MODIFIER: fprintf(output, "LETTER_MODIFIER "); break; case XML_REGEXP_LETTER_OTHERS: fprintf(output, "LETTER_OTHERS "); break; case XML_REGEXP_MARK: fprintf(output, "MARK "); break; case XML_REGEXP_MARK_NONSPACING: fprintf(output, "MARK_NONSPACING "); break; case XML_REGEXP_MARK_SPACECOMBINING: fprintf(output, "MARK_SPACECOMBINING "); break; case XML_REGEXP_MARK_ENCLOSING: fprintf(output, "MARK_ENCLOSING "); break; case XML_REGEXP_NUMBER: fprintf(output, "NUMBER "); break; case XML_REGEXP_NUMBER_DECIMAL: fprintf(output, "NUMBER_DECIMAL "); break; case XML_REGEXP_NUMBER_LETTER: fprintf(output, "NUMBER_LETTER "); break; case XML_REGEXP_NUMBER_OTHERS: fprintf(output, "NUMBER_OTHERS "); break; case XML_REGEXP_PUNCT: fprintf(output, "PUNCT "); break; case XML_REGEXP_PUNCT_CONNECTOR: fprintf(output, "PUNCT_CONNECTOR "); break; case XML_REGEXP_PUNCT_DASH: fprintf(output, "PUNCT_DASH "); break; case XML_REGEXP_PUNCT_OPEN: fprintf(output, "PUNCT_OPEN "); break; case XML_REGEXP_PUNCT_CLOSE: fprintf(output, "PUNCT_CLOSE "); break; case XML_REGEXP_PUNCT_INITQUOTE: fprintf(output, "PUNCT_INITQUOTE "); break; case XML_REGEXP_PUNCT_FINQUOTE: fprintf(output, "PUNCT_FINQUOTE "); break; case XML_REGEXP_PUNCT_OTHERS: fprintf(output, "PUNCT_OTHERS "); break; case XML_REGEXP_SEPAR: fprintf(output, "SEPAR "); break; case XML_REGEXP_SEPAR_SPACE: fprintf(output, "SEPAR_SPACE "); break; case XML_REGEXP_SEPAR_LINE: fprintf(output, "SEPAR_LINE "); break; case XML_REGEXP_SEPAR_PARA: fprintf(output, "SEPAR_PARA "); break; case XML_REGEXP_SYMBOL: fprintf(output, "SYMBOL "); break; case XML_REGEXP_SYMBOL_MATH: fprintf(output, "SYMBOL_MATH "); break; case XML_REGEXP_SYMBOL_CURRENCY: fprintf(output, "SYMBOL_CURRENCY "); break; case XML_REGEXP_SYMBOL_MODIFIER: fprintf(output, "SYMBOL_MODIFIER "); break; case XML_REGEXP_SYMBOL_OTHERS: fprintf(output, "SYMBOL_OTHERS "); break; case XML_REGEXP_OTHER: fprintf(output, "OTHER "); break; case XML_REGEXP_OTHER_CONTROL: fprintf(output, "OTHER_CONTROL "); break; case XML_REGEXP_OTHER_FORMAT: fprintf(output, "OTHER_FORMAT "); break; case XML_REGEXP_OTHER_PRIVATE: fprintf(output, "OTHER_PRIVATE "); break; case XML_REGEXP_OTHER_NA: fprintf(output, "OTHER_NA "); break; case XML_REGEXP_BLOCK_NAME: fprintf(output, "BLOCK "); break; } } static void xmlRegPrintQuantType(FILE *output, xmlRegQuantType type) { switch (type) { case XML_REGEXP_QUANT_EPSILON: fprintf(output, "epsilon "); break; case XML_REGEXP_QUANT_ONCE: fprintf(output, "once "); break; case XML_REGEXP_QUANT_OPT: fprintf(output, "? "); break; case XML_REGEXP_QUANT_MULT: fprintf(output, "* "); break; case XML_REGEXP_QUANT_PLUS: fprintf(output, "+ "); break; case XML_REGEXP_QUANT_RANGE: fprintf(output, "range "); break; case XML_REGEXP_QUANT_ONCEONLY: fprintf(output, "onceonly "); break; case XML_REGEXP_QUANT_ALL: fprintf(output, "all "); break; } } static void xmlRegPrintRange(FILE *output, xmlRegRangePtr range) { fprintf(output, " range: "); if (range->neg) fprintf(output, "negative "); xmlRegPrintAtomType(output, range->type); fprintf(output, "%c - %c\n", range->start, range->end); } static void xmlRegPrintAtom(FILE *output, xmlRegAtomPtr atom) { fprintf(output, " atom: "); if (atom == NULL) { fprintf(output, "NULL\n"); return; } if (atom->neg) fprintf(output, "not "); xmlRegPrintAtomType(output, atom->type); xmlRegPrintQuantType(output, atom->quant); if (atom->quant == XML_REGEXP_QUANT_RANGE) fprintf(output, "%d-%d ", atom->min, atom->max); if (atom->type == XML_REGEXP_STRING) fprintf(output, "'%s' ", (char *) atom->valuep); if (atom->type == XML_REGEXP_CHARVAL) fprintf(output, "char %c\n", atom->codepoint); else if (atom->type == XML_REGEXP_RANGES) { int i; fprintf(output, "%d entries\n", atom->nbRanges); for (i = 0; i < atom->nbRanges;i++) xmlRegPrintRange(output, atom->ranges[i]); } else if (atom->type == XML_REGEXP_SUBREG) { fprintf(output, "start %d end %d\n", atom->start->no, atom->stop->no); } else { fprintf(output, "\n"); } } static void xmlRegPrintTrans(FILE *output, xmlRegTransPtr trans) { fprintf(output, " trans: "); if (trans == NULL) { fprintf(output, "NULL\n"); return; } if (trans->to < 0) { fprintf(output, "removed\n"); return; } if (trans->nd != 0) { if (trans->nd == 2) fprintf(output, "last not determinist, "); else fprintf(output, "not determinist, "); } if (trans->counter >= 0) { fprintf(output, "counted %d, ", trans->counter); } if (trans->count == REGEXP_ALL_COUNTER) { fprintf(output, "all transition, "); } else if (trans->count >= 0) { fprintf(output, "count based %d, ", trans->count); } if (trans->atom == NULL) { fprintf(output, "epsilon to %d\n", trans->to); return; } if (trans->atom->type == XML_REGEXP_CHARVAL) fprintf(output, "char %c ", trans->atom->codepoint); fprintf(output, "atom %d, to %d\n", trans->atom->no, trans->to); } static void xmlRegPrintState(FILE *output, xmlRegStatePtr state) { int i; fprintf(output, " state: "); if (state == NULL) { fprintf(output, "NULL\n"); return; } if (state->type == XML_REGEXP_START_STATE) fprintf(output, "START "); if (state->type == XML_REGEXP_FINAL_STATE) fprintf(output, "FINAL "); fprintf(output, "%d, %d transitions:\n", state->no, state->nbTrans); for (i = 0;i < state->nbTrans; i++) { xmlRegPrintTrans(output, &(state->trans[i])); } } /************************************************************************ * * * Finite Automata structures manipulations * * * ************************************************************************/ static xmlRegRangePtr xmlRegAtomAddRange(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom, int neg, xmlRegAtomType type, int start, int end, xmlChar *blockName) { xmlRegRangePtr range; if (atom == NULL) { ERROR("add range: atom is NULL"); return(NULL); } if (atom->type != XML_REGEXP_RANGES) { ERROR("add range: atom is not ranges"); return(NULL); } if (atom->maxRanges == 0) { atom->maxRanges = 4; atom->ranges = (xmlRegRangePtr *) xmlMalloc(atom->maxRanges * sizeof(xmlRegRangePtr)); if (atom->ranges == NULL) { xmlRegexpErrMemory(ctxt, "adding ranges"); atom->maxRanges = 0; return(NULL); } } else if (atom->nbRanges >= atom->maxRanges) { xmlRegRangePtr *tmp; atom->maxRanges *= 2; tmp = (xmlRegRangePtr *) xmlRealloc(atom->ranges, atom->maxRanges * sizeof(xmlRegRangePtr)); if (tmp == NULL) { xmlRegexpErrMemory(ctxt, "adding ranges"); atom->maxRanges /= 2; return(NULL); } atom->ranges = tmp; } range = xmlRegNewRange(ctxt, neg, type, start, end); if (range == NULL) return(NULL); range->blockName = blockName; atom->ranges[atom->nbRanges++] = range; return(range); } static int xmlRegGetCounter(xmlRegParserCtxtPtr ctxt) { if (ctxt->maxCounters == 0) { ctxt->maxCounters = 4; ctxt->counters = (xmlRegCounter *) xmlMalloc(ctxt->maxCounters * sizeof(xmlRegCounter)); if (ctxt->counters == NULL) { xmlRegexpErrMemory(ctxt, "allocating counter"); ctxt->maxCounters = 0; return(-1); } } else if (ctxt->nbCounters >= ctxt->maxCounters) { xmlRegCounter *tmp; ctxt->maxCounters *= 2; tmp = (xmlRegCounter *) xmlRealloc(ctxt->counters, ctxt->maxCounters * sizeof(xmlRegCounter)); if (tmp == NULL) { xmlRegexpErrMemory(ctxt, "allocating counter"); ctxt->maxCounters /= 2; return(-1); } ctxt->counters = tmp; } ctxt->counters[ctxt->nbCounters].min = -1; ctxt->counters[ctxt->nbCounters].max = -1; return(ctxt->nbCounters++); } static int xmlRegAtomPush(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom) { if (atom == NULL) { ERROR("atom push: atom is NULL"); return(-1); } if (ctxt->nbAtoms >= ctxt->maxAtoms) { size_t newSize = ctxt->maxAtoms ? ctxt->maxAtoms * 2 : 4; xmlRegAtomPtr *tmp; tmp = xmlRealloc(ctxt->atoms, newSize * sizeof(xmlRegAtomPtr)); if (tmp == NULL) { xmlRegexpErrMemory(ctxt, "allocating counter"); return(-1); } ctxt->atoms = tmp; ctxt->maxAtoms = newSize; } atom->no = ctxt->nbAtoms; ctxt->atoms[ctxt->nbAtoms++] = atom; return(0); } static void xmlRegStateAddTransTo(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr target, int from) { if (target->maxTransTo == 0) { target->maxTransTo = 8; target->transTo = (int *) xmlMalloc(target->maxTransTo * sizeof(int)); if (target->transTo == NULL) { xmlRegexpErrMemory(ctxt, "adding transition"); target->maxTransTo = 0; return; } } else if (target->nbTransTo >= target->maxTransTo) { int *tmp; target->maxTransTo *= 2; tmp = (int *) xmlRealloc(target->transTo, target->maxTransTo * sizeof(int)); if (tmp == NULL) { xmlRegexpErrMemory(ctxt, "adding transition"); target->maxTransTo /= 2; return; } target->transTo = tmp; } target->transTo[target->nbTransTo] = from; target->nbTransTo++; } static void xmlRegStateAddTrans(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state, xmlRegAtomPtr atom, xmlRegStatePtr target, int counter, int count) { int nrtrans; if (state == NULL) { ERROR("add state: state is NULL"); return; } if (target == NULL) { ERROR("add state: target is NULL"); return; } /* * Other routines follow the philosophy 'When in doubt, add a transition' * so we check here whether such a transition is already present and, if * so, silently ignore this request. */ for (nrtrans = state->nbTrans - 1; nrtrans >= 0; nrtrans--) { xmlRegTransPtr trans = &(state->trans[nrtrans]); if ((trans->atom == atom) && (trans->to == target->no) && (trans->counter == counter) && (trans->count == count)) { return; } } if (state->maxTrans == 0) { state->maxTrans = 8; state->trans = (xmlRegTrans *) xmlMalloc(state->maxTrans * sizeof(xmlRegTrans)); if (state->trans == NULL) { xmlRegexpErrMemory(ctxt, "adding transition"); state->maxTrans = 0; return; } } else if (state->nbTrans >= state->maxTrans) { xmlRegTrans *tmp; state->maxTrans *= 2; tmp = (xmlRegTrans *) xmlRealloc(state->trans, state->maxTrans * sizeof(xmlRegTrans)); if (tmp == NULL) { xmlRegexpErrMemory(ctxt, "adding transition"); state->maxTrans /= 2; return; } state->trans = tmp; } state->trans[state->nbTrans].atom = atom; state->trans[state->nbTrans].to = target->no; state->trans[state->nbTrans].counter = counter; state->trans[state->nbTrans].count = count; state->trans[state->nbTrans].nd = 0; state->nbTrans++; xmlRegStateAddTransTo(ctxt, target, state->no); } static xmlRegStatePtr xmlRegStatePush(xmlRegParserCtxtPtr ctxt) { xmlRegStatePtr state; if (ctxt->nbStates >= ctxt->maxStates) { size_t newSize = ctxt->maxStates ? ctxt->maxStates * 2 : 4; xmlRegStatePtr *tmp; tmp = xmlRealloc(ctxt->states, newSize * sizeof(tmp[0])); if (tmp == NULL) { xmlRegexpErrMemory(ctxt, "adding state"); return(NULL); } ctxt->states = tmp; ctxt->maxStates = newSize; } state = xmlRegNewState(ctxt); if (state == NULL) return(NULL); state->no = ctxt->nbStates; ctxt->states[ctxt->nbStates++] = state; return(state); } /** * xmlFAGenerateAllTransition: * @ctxt: a regexp parser context * @from: the from state * @to: the target state or NULL for building a new one * @lax: * */ static int xmlFAGenerateAllTransition(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr from, xmlRegStatePtr to, int lax) { if (to == NULL) { to = xmlRegStatePush(ctxt); if (to == NULL) return(-1); ctxt->state = to; } if (lax) xmlRegStateAddTrans(ctxt, from, NULL, to, -1, REGEXP_ALL_LAX_COUNTER); else xmlRegStateAddTrans(ctxt, from, NULL, to, -1, REGEXP_ALL_COUNTER); return(0); } /** * xmlFAGenerateEpsilonTransition: * @ctxt: a regexp parser context * @from: the from state * @to: the target state or NULL for building a new one * */ static int xmlFAGenerateEpsilonTransition(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr from, xmlRegStatePtr to) { if (to == NULL) { to = xmlRegStatePush(ctxt); if (to == NULL) return(-1); ctxt->state = to; } xmlRegStateAddTrans(ctxt, from, NULL, to, -1, -1); return(0); } /** * xmlFAGenerateCountedEpsilonTransition: * @ctxt: a regexp parser context * @from: the from state * @to: the target state or NULL for building a new one * counter: the counter for that transition * */ static int xmlFAGenerateCountedEpsilonTransition(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr from, xmlRegStatePtr to, int counter) { if (to == NULL) { to = xmlRegStatePush(ctxt); if (to == NULL) return(-1); ctxt->state = to; } xmlRegStateAddTrans(ctxt, from, NULL, to, counter, -1); return(0); } /** * xmlFAGenerateCountedTransition: * @ctxt: a regexp parser context * @from: the from state * @to: the target state or NULL for building a new one * counter: the counter for that transition * */ static int xmlFAGenerateCountedTransition(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr from, xmlRegStatePtr to, int counter) { if (to == NULL) { to = xmlRegStatePush(ctxt); if (to == NULL) return(-1); ctxt->state = to; } xmlRegStateAddTrans(ctxt, from, NULL, to, -1, counter); return(0); } /** * xmlFAGenerateTransitions: * @ctxt: a regexp parser context * @from: the from state * @to: the target state or NULL for building a new one * @atom: the atom generating the transition * * Returns 0 if success and -1 in case of error. */ static int xmlFAGenerateTransitions(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr from, xmlRegStatePtr to, xmlRegAtomPtr atom) { xmlRegStatePtr end; int nullable = 0; if (atom == NULL) { ERROR("generate transition: atom == NULL"); return(-1); } if (atom->type == XML_REGEXP_SUBREG) { /* * this is a subexpression handling one should not need to * create a new node except for XML_REGEXP_QUANT_RANGE. */ if ((to != NULL) && (atom->stop != to) && (atom->quant != XML_REGEXP_QUANT_RANGE)) { /* * Generate an epsilon transition to link to the target */ xmlFAGenerateEpsilonTransition(ctxt, atom->stop, to); #ifdef DV } else if ((to == NULL) && (atom->quant != XML_REGEXP_QUANT_RANGE) && (atom->quant != XML_REGEXP_QUANT_ONCE)) { to = xmlRegStatePush(ctxt, to); if (to == NULL) return(-1); ctxt->state = to; xmlFAGenerateEpsilonTransition(ctxt, atom->stop, to); #endif } switch (atom->quant) { case XML_REGEXP_QUANT_OPT: atom->quant = XML_REGEXP_QUANT_ONCE; /* * transition done to the state after end of atom. * 1. set transition from atom start to new state * 2. set transition from atom end to this state. */ if (to == NULL) { xmlFAGenerateEpsilonTransition(ctxt, atom->start, 0); xmlFAGenerateEpsilonTransition(ctxt, atom->stop, ctxt->state); } else { xmlFAGenerateEpsilonTransition(ctxt, atom->start, to); } break; case XML_REGEXP_QUANT_MULT: atom->quant = XML_REGEXP_QUANT_ONCE; xmlFAGenerateEpsilonTransition(ctxt, atom->start, atom->stop); xmlFAGenerateEpsilonTransition(ctxt, atom->stop, atom->start); break; case XML_REGEXP_QUANT_PLUS: atom->quant = XML_REGEXP_QUANT_ONCE; xmlFAGenerateEpsilonTransition(ctxt, atom->stop, atom->start); break; case XML_REGEXP_QUANT_RANGE: { int counter; xmlRegStatePtr inter, newstate; /* * create the final state now if needed */ if (to != NULL) { newstate = to; } else { newstate = xmlRegStatePush(ctxt); if (newstate == NULL) return(-1); } /* * The principle here is to use counted transition * to avoid explosion in the number of states in the * graph. This is clearly more complex but should not * be exploitable at runtime. */ if ((atom->min == 0) && (atom->start0 == NULL)) { xmlRegAtomPtr copy; /* * duplicate a transition based on atom to count next * occurrences after 1. We cannot loop to atom->start * directly because we need an epsilon transition to * newstate. */ /* ???? For some reason it seems we never reach that case, I suppose this got optimized out before when building the automata */ copy = xmlRegCopyAtom(ctxt, atom); if (copy == NULL) return(-1); copy->quant = XML_REGEXP_QUANT_ONCE; copy->min = 0; copy->max = 0; if (xmlFAGenerateTransitions(ctxt, atom->start, NULL, copy) < 0) { xmlRegFreeAtom(copy); return(-1); } inter = ctxt->state; counter = xmlRegGetCounter(ctxt); if (counter < 0) return(-1); ctxt->counters[counter].min = atom->min - 1; ctxt->counters[counter].max = atom->max - 1; /* count the number of times we see it again */ xmlFAGenerateCountedEpsilonTransition(ctxt, inter, atom->stop, counter); /* allow a way out based on the count */ xmlFAGenerateCountedTransition(ctxt, inter, newstate, counter); /* and also allow a direct exit for 0 */ xmlFAGenerateEpsilonTransition(ctxt, atom->start, newstate); } else { /* * either we need the atom at least once or there * is an atom->start0 allowing to easily plug the * epsilon transition. */ counter = xmlRegGetCounter(ctxt); if (counter < 0) return(-1); ctxt->counters[counter].min = atom->min - 1; ctxt->counters[counter].max = atom->max - 1; /* allow a way out based on the count */ xmlFAGenerateCountedTransition(ctxt, atom->stop, newstate, counter); /* count the number of times we see it again */ xmlFAGenerateCountedEpsilonTransition(ctxt, atom->stop, atom->start, counter); /* and if needed allow a direct exit for 0 */ if (atom->min == 0) xmlFAGenerateEpsilonTransition(ctxt, atom->start0, newstate); } atom->min = 0; atom->max = 0; atom->quant = XML_REGEXP_QUANT_ONCE; ctxt->state = newstate; } default: break; } if (xmlRegAtomPush(ctxt, atom) < 0) return(-1); return(0); } if ((atom->min == 0) && (atom->max == 0) && (atom->quant == XML_REGEXP_QUANT_RANGE)) { /* * we can discard the atom and generate an epsilon transition instead */ if (to == NULL) { to = xmlRegStatePush(ctxt); if (to == NULL) return(-1); } xmlFAGenerateEpsilonTransition(ctxt, from, to); ctxt->state = to; xmlRegFreeAtom(atom); return(0); } if (to == NULL) { to = xmlRegStatePush(ctxt); if (to == NULL) return(-1); } end = to; if ((atom->quant == XML_REGEXP_QUANT_MULT) || (atom->quant == XML_REGEXP_QUANT_PLUS)) { /* * Do not pollute the target state by adding transitions from * it as it is likely to be the shared target of multiple branches. * So isolate with an epsilon transition. */ xmlRegStatePtr tmp; tmp = xmlRegStatePush(ctxt); if (tmp == NULL) return(-1); xmlFAGenerateEpsilonTransition(ctxt, tmp, to); to = tmp; } if ((atom->quant == XML_REGEXP_QUANT_RANGE) && (atom->min == 0) && (atom->max > 0)) { nullable = 1; atom->min = 1; if (atom->max == 1) atom->quant = XML_REGEXP_QUANT_OPT; } xmlRegStateAddTrans(ctxt, from, atom, to, -1, -1); ctxt->state = end; switch (atom->quant) { case XML_REGEXP_QUANT_OPT: atom->quant = XML_REGEXP_QUANT_ONCE; xmlFAGenerateEpsilonTransition(ctxt, from, to); break; case XML_REGEXP_QUANT_MULT: atom->quant = XML_REGEXP_QUANT_ONCE; xmlFAGenerateEpsilonTransition(ctxt, from, to); xmlRegStateAddTrans(ctxt, to, atom, to, -1, -1); break; case XML_REGEXP_QUANT_PLUS: atom->quant = XML_REGEXP_QUANT_ONCE; xmlRegStateAddTrans(ctxt, to, atom, to, -1, -1); break; case XML_REGEXP_QUANT_RANGE: if (nullable) xmlFAGenerateEpsilonTransition(ctxt, from, to); break; default: break; } if (xmlRegAtomPush(ctxt, atom) < 0) return(-1); return(0); } /** * xmlFAReduceEpsilonTransitions: * @ctxt: a regexp parser context * @fromnr: the from state * @tonr: the to state * @counter: should that transition be associated to a counted * */ static void xmlFAReduceEpsilonTransitions(xmlRegParserCtxtPtr ctxt, int fromnr, int tonr, int counter) { int transnr; xmlRegStatePtr from; xmlRegStatePtr to; from = ctxt->states[fromnr]; if (from == NULL) return; to = ctxt->states[tonr]; if (to == NULL) return; if ((to->mark == XML_REGEXP_MARK_START) || (to->mark == XML_REGEXP_MARK_VISITED)) return; to->mark = XML_REGEXP_MARK_VISITED; if (to->type == XML_REGEXP_FINAL_STATE) { from->type = XML_REGEXP_FINAL_STATE; } for (transnr = 0;transnr < to->nbTrans;transnr++) { xmlRegTransPtr t1 = &to->trans[transnr]; int tcounter; if (t1->to < 0) continue; if (t1->counter >= 0) { /* assert(counter < 0); */ tcounter = t1->counter; } else { tcounter = counter; } if (t1->atom == NULL) { /* * Don't remove counted transitions * Don't loop either */ if (t1->to != fromnr) { if (t1->count >= 0) { xmlRegStateAddTrans(ctxt, from, NULL, ctxt->states[t1->to], -1, t1->count); } else { xmlFAReduceEpsilonTransitions(ctxt, fromnr, t1->to, tcounter); } } } else { xmlRegStateAddTrans(ctxt, from, t1->atom, ctxt->states[t1->to], tcounter, -1); } } } /** * xmlFAFinishReduceEpsilonTransitions: * @ctxt: a regexp parser context * @fromnr: the from state * @tonr: the to state * @counter: should that transition be associated to a counted * */ static void xmlFAFinishReduceEpsilonTransitions(xmlRegParserCtxtPtr ctxt, int tonr) { int transnr; xmlRegStatePtr to; to = ctxt->states[tonr]; if (to == NULL) return; if ((to->mark == XML_REGEXP_MARK_START) || (to->mark == XML_REGEXP_MARK_NORMAL)) return; to->mark = XML_REGEXP_MARK_NORMAL; for (transnr = 0;transnr < to->nbTrans;transnr++) { xmlRegTransPtr t1 = &to->trans[transnr]; if ((t1->to >= 0) && (t1->atom == NULL)) xmlFAFinishReduceEpsilonTransitions(ctxt, t1->to); } } /** * xmlFAEliminateSimpleEpsilonTransitions: * @ctxt: a regexp parser context * * Eliminating general epsilon transitions can get costly in the general * algorithm due to the large amount of generated new transitions and * associated comparisons. However for simple epsilon transition used just * to separate building blocks when generating the automata this can be * reduced to state elimination: * - if there exists an epsilon from X to Y * - if there is no other transition from X * then X and Y are semantically equivalent and X can be eliminated * If X is the start state then make Y the start state, else replace the * target of all transitions to X by transitions to Y. * * If X is a final state, skip it. * Otherwise it would be necessary to manipulate counters for this case when * eliminating state 2: * State 1 has a transition with an atom to state 2. * State 2 is final and has an epsilon transition to state 1. */ static void xmlFAEliminateSimpleEpsilonTransitions(xmlRegParserCtxtPtr ctxt) { int statenr, i, j, newto; xmlRegStatePtr state, tmp; for (statenr = 0;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if (state == NULL) continue; if (state->nbTrans != 1) continue; if (state->type == XML_REGEXP_UNREACH_STATE || state->type == XML_REGEXP_FINAL_STATE) continue; /* is the only transition out a basic transition */ if ((state->trans[0].atom == NULL) && (state->trans[0].to >= 0) && (state->trans[0].to != statenr) && (state->trans[0].counter < 0) && (state->trans[0].count < 0)) { newto = state->trans[0].to; if (state->type == XML_REGEXP_START_STATE) { } else { for (i = 0;i < state->nbTransTo;i++) { tmp = ctxt->states[state->transTo[i]]; for (j = 0;j < tmp->nbTrans;j++) { if (tmp->trans[j].to == statenr) { tmp->trans[j].to = -1; xmlRegStateAddTrans(ctxt, tmp, tmp->trans[j].atom, ctxt->states[newto], tmp->trans[j].counter, tmp->trans[j].count); } } } if (state->type == XML_REGEXP_FINAL_STATE) ctxt->states[newto]->type = XML_REGEXP_FINAL_STATE; /* eliminate the transition completely */ state->nbTrans = 0; state->type = XML_REGEXP_UNREACH_STATE; } } } } /** * xmlFAEliminateEpsilonTransitions: * @ctxt: a regexp parser context * */ static void xmlFAEliminateEpsilonTransitions(xmlRegParserCtxtPtr ctxt) { int statenr, transnr; xmlRegStatePtr state; int has_epsilon; if (ctxt->states == NULL) return; /* * Eliminate simple epsilon transition and the associated unreachable * states. */ xmlFAEliminateSimpleEpsilonTransitions(ctxt); for (statenr = 0;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if ((state != NULL) && (state->type == XML_REGEXP_UNREACH_STATE)) { xmlRegFreeState(state); ctxt->states[statenr] = NULL; } } has_epsilon = 0; /* * Build the completed transitions bypassing the epsilons * Use a marking algorithm to avoid loops * Mark sink states too. * Process from the latest states backward to the start when * there is long cascading epsilon chains this minimize the * recursions and transition compares when adding the new ones */ for (statenr = ctxt->nbStates - 1;statenr >= 0;statenr--) { state = ctxt->states[statenr]; if (state == NULL) continue; if ((state->nbTrans == 0) && (state->type != XML_REGEXP_FINAL_STATE)) { state->type = XML_REGEXP_SINK_STATE; } for (transnr = 0;transnr < state->nbTrans;transnr++) { if ((state->trans[transnr].atom == NULL) && (state->trans[transnr].to >= 0)) { if (state->trans[transnr].to == statenr) { state->trans[transnr].to = -1; } else if (state->trans[transnr].count < 0) { int newto = state->trans[transnr].to; has_epsilon = 1; state->trans[transnr].to = -2; state->mark = XML_REGEXP_MARK_START; xmlFAReduceEpsilonTransitions(ctxt, statenr, newto, state->trans[transnr].counter); xmlFAFinishReduceEpsilonTransitions(ctxt, newto); state->mark = XML_REGEXP_MARK_NORMAL; } } } } /* * Eliminate the epsilon transitions */ if (has_epsilon) { for (statenr = 0;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if (state == NULL) continue; for (transnr = 0;transnr < state->nbTrans;transnr++) { xmlRegTransPtr trans = &(state->trans[transnr]); if ((trans->atom == NULL) && (trans->count < 0) && (trans->to >= 0)) { trans->to = -1; } } } } /* * Use this pass to detect unreachable states too */ for (statenr = 0;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if (state != NULL) state->reached = XML_REGEXP_MARK_NORMAL; } state = ctxt->states[0]; if (state != NULL) state->reached = XML_REGEXP_MARK_START; while (state != NULL) { xmlRegStatePtr target = NULL; state->reached = XML_REGEXP_MARK_VISITED; /* * Mark all states reachable from the current reachable state */ for (transnr = 0;transnr < state->nbTrans;transnr++) { if ((state->trans[transnr].to >= 0) && ((state->trans[transnr].atom != NULL) || (state->trans[transnr].count >= 0))) { int newto = state->trans[transnr].to; if (ctxt->states[newto] == NULL) continue; if (ctxt->states[newto]->reached == XML_REGEXP_MARK_NORMAL) { ctxt->states[newto]->reached = XML_REGEXP_MARK_START; target = ctxt->states[newto]; } } } /* * find the next accessible state not explored */ if (target == NULL) { for (statenr = 1;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if ((state != NULL) && (state->reached == XML_REGEXP_MARK_START)) { target = state; break; } } } state = target; } for (statenr = 0;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if ((state != NULL) && (state->reached == XML_REGEXP_MARK_NORMAL)) { xmlRegFreeState(state); ctxt->states[statenr] = NULL; } } } static int xmlFACompareRanges(xmlRegRangePtr range1, xmlRegRangePtr range2) { int ret = 0; if ((range1->type == XML_REGEXP_RANGES) || (range2->type == XML_REGEXP_RANGES) || (range2->type == XML_REGEXP_SUBREG) || (range1->type == XML_REGEXP_SUBREG) || (range1->type == XML_REGEXP_STRING) || (range2->type == XML_REGEXP_STRING)) return(-1); /* put them in order */ if (range1->type > range2->type) { xmlRegRangePtr tmp; tmp = range1; range1 = range2; range2 = tmp; } if ((range1->type == XML_REGEXP_ANYCHAR) || (range2->type == XML_REGEXP_ANYCHAR)) { ret = 1; } else if ((range1->type == XML_REGEXP_EPSILON) || (range2->type == XML_REGEXP_EPSILON)) { return(0); } else if (range1->type == range2->type) { if (range1->type != XML_REGEXP_CHARVAL) ret = 1; else if ((range1->end < range2->start) || (range2->end < range1->start)) ret = 0; else ret = 1; } else if (range1->type == XML_REGEXP_CHARVAL) { int codepoint; int neg = 0; /* * just check all codepoints in the range for acceptance, * this is usually way cheaper since done only once at * compilation than testing over and over at runtime or * pushing too many states when evaluating. */ if (((range1->neg == 0) && (range2->neg != 0)) || ((range1->neg != 0) && (range2->neg == 0))) neg = 1; for (codepoint = range1->start;codepoint <= range1->end ;codepoint++) { ret = xmlRegCheckCharacterRange(range2->type, codepoint, 0, range2->start, range2->end, range2->blockName); if (ret < 0) return(-1); if (((neg == 1) && (ret == 0)) || ((neg == 0) && (ret == 1))) return(1); } return(0); } else if ((range1->type == XML_REGEXP_BLOCK_NAME) || (range2->type == XML_REGEXP_BLOCK_NAME)) { if (range1->type == range2->type) { ret = xmlStrEqual(range1->blockName, range2->blockName); } else { /* * comparing a block range with anything else is way * too costly, and maintaining the table is like too much * memory too, so let's force the automata to save state * here. */ return(1); } } else if ((range1->type < XML_REGEXP_LETTER) || (range2->type < XML_REGEXP_LETTER)) { if ((range1->type == XML_REGEXP_ANYSPACE) && (range2->type == XML_REGEXP_NOTSPACE)) ret = 0; else if ((range1->type == XML_REGEXP_INITNAME) && (range2->type == XML_REGEXP_NOTINITNAME)) ret = 0; else if ((range1->type == XML_REGEXP_NAMECHAR) && (range2->type == XML_REGEXP_NOTNAMECHAR)) ret = 0; else if ((range1->type == XML_REGEXP_DECIMAL) && (range2->type == XML_REGEXP_NOTDECIMAL)) ret = 0; else if ((range1->type == XML_REGEXP_REALCHAR) && (range2->type == XML_REGEXP_NOTREALCHAR)) ret = 0; else { /* same thing to limit complexity */ return(1); } } else { ret = 0; /* range1->type < range2->type here */ switch (range1->type) { case XML_REGEXP_LETTER: /* all disjoint except in the subgroups */ if ((range2->type == XML_REGEXP_LETTER_UPPERCASE) || (range2->type == XML_REGEXP_LETTER_LOWERCASE) || (range2->type == XML_REGEXP_LETTER_TITLECASE) || (range2->type == XML_REGEXP_LETTER_MODIFIER) || (range2->type == XML_REGEXP_LETTER_OTHERS)) ret = 1; break; case XML_REGEXP_MARK: if ((range2->type == XML_REGEXP_MARK_NONSPACING) || (range2->type == XML_REGEXP_MARK_SPACECOMBINING) || (range2->type == XML_REGEXP_MARK_ENCLOSING)) ret = 1; break; case XML_REGEXP_NUMBER: if ((range2->type == XML_REGEXP_NUMBER_DECIMAL) || (range2->type == XML_REGEXP_NUMBER_LETTER) || (range2->type == XML_REGEXP_NUMBER_OTHERS)) ret = 1; break; case XML_REGEXP_PUNCT: if ((range2->type == XML_REGEXP_PUNCT_CONNECTOR) || (range2->type == XML_REGEXP_PUNCT_DASH) || (range2->type == XML_REGEXP_PUNCT_OPEN) || (range2->type == XML_REGEXP_PUNCT_CLOSE) || (range2->type == XML_REGEXP_PUNCT_INITQUOTE) || (range2->type == XML_REGEXP_PUNCT_FINQUOTE) || (range2->type == XML_REGEXP_PUNCT_OTHERS)) ret = 1; break; case XML_REGEXP_SEPAR: if ((range2->type == XML_REGEXP_SEPAR_SPACE) || (range2->type == XML_REGEXP_SEPAR_LINE) || (range2->type == XML_REGEXP_SEPAR_PARA)) ret = 1; break; case XML_REGEXP_SYMBOL: if ((range2->type == XML_REGEXP_SYMBOL_MATH) || (range2->type == XML_REGEXP_SYMBOL_CURRENCY) || (range2->type == XML_REGEXP_SYMBOL_MODIFIER) || (range2->type == XML_REGEXP_SYMBOL_OTHERS)) ret = 1; break; case XML_REGEXP_OTHER: if ((range2->type == XML_REGEXP_OTHER_CONTROL) || (range2->type == XML_REGEXP_OTHER_FORMAT) || (range2->type == XML_REGEXP_OTHER_PRIVATE)) ret = 1; break; default: if ((range2->type >= XML_REGEXP_LETTER) && (range2->type < XML_REGEXP_BLOCK_NAME)) ret = 0; else { /* safety net ! */ return(1); } } } if (((range1->neg == 0) && (range2->neg != 0)) || ((range1->neg != 0) && (range2->neg == 0))) ret = !ret; return(ret); } /** * xmlFACompareAtomTypes: * @type1: an atom type * @type2: an atom type * * Compares two atoms type to check whether they intersect in some ways, * this is used by xmlFACompareAtoms only * * Returns 1 if they may intersect and 0 otherwise */ static int xmlFACompareAtomTypes(xmlRegAtomType type1, xmlRegAtomType type2) { if ((type1 == XML_REGEXP_EPSILON) || (type1 == XML_REGEXP_CHARVAL) || (type1 == XML_REGEXP_RANGES) || (type1 == XML_REGEXP_SUBREG) || (type1 == XML_REGEXP_STRING) || (type1 == XML_REGEXP_ANYCHAR)) return(1); if ((type2 == XML_REGEXP_EPSILON) || (type2 == XML_REGEXP_CHARVAL) || (type2 == XML_REGEXP_RANGES) || (type2 == XML_REGEXP_SUBREG) || (type2 == XML_REGEXP_STRING) || (type2 == XML_REGEXP_ANYCHAR)) return(1); if (type1 == type2) return(1); /* simplify subsequent compares by making sure type1 < type2 */ if (type1 > type2) { xmlRegAtomType tmp = type1; type1 = type2; type2 = tmp; } switch (type1) { case XML_REGEXP_ANYSPACE: /* \s */ /* can't be a letter, number, mark, punctuation, symbol */ if ((type2 == XML_REGEXP_NOTSPACE) || ((type2 >= XML_REGEXP_LETTER) && (type2 <= XML_REGEXP_LETTER_OTHERS)) || ((type2 >= XML_REGEXP_NUMBER) && (type2 <= XML_REGEXP_NUMBER_OTHERS)) || ((type2 >= XML_REGEXP_MARK) && (type2 <= XML_REGEXP_MARK_ENCLOSING)) || ((type2 >= XML_REGEXP_PUNCT) && (type2 <= XML_REGEXP_PUNCT_OTHERS)) || ((type2 >= XML_REGEXP_SYMBOL) && (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ) return(0); break; case XML_REGEXP_NOTSPACE: /* \S */ break; case XML_REGEXP_INITNAME: /* \l */ /* can't be a number, mark, separator, punctuation, symbol or other */ if ((type2 == XML_REGEXP_NOTINITNAME) || ((type2 >= XML_REGEXP_NUMBER) && (type2 <= XML_REGEXP_NUMBER_OTHERS)) || ((type2 >= XML_REGEXP_MARK) && (type2 <= XML_REGEXP_MARK_ENCLOSING)) || ((type2 >= XML_REGEXP_SEPAR) && (type2 <= XML_REGEXP_SEPAR_PARA)) || ((type2 >= XML_REGEXP_PUNCT) && (type2 <= XML_REGEXP_PUNCT_OTHERS)) || ((type2 >= XML_REGEXP_SYMBOL) && (type2 <= XML_REGEXP_SYMBOL_OTHERS)) || ((type2 >= XML_REGEXP_OTHER) && (type2 <= XML_REGEXP_OTHER_NA)) ) return(0); break; case XML_REGEXP_NOTINITNAME: /* \L */ break; case XML_REGEXP_NAMECHAR: /* \c */ /* can't be a mark, separator, punctuation, symbol or other */ if ((type2 == XML_REGEXP_NOTNAMECHAR) || ((type2 >= XML_REGEXP_MARK) && (type2 <= XML_REGEXP_MARK_ENCLOSING)) || ((type2 >= XML_REGEXP_PUNCT) && (type2 <= XML_REGEXP_PUNCT_OTHERS)) || ((type2 >= XML_REGEXP_SEPAR) && (type2 <= XML_REGEXP_SEPAR_PARA)) || ((type2 >= XML_REGEXP_SYMBOL) && (type2 <= XML_REGEXP_SYMBOL_OTHERS)) || ((type2 >= XML_REGEXP_OTHER) && (type2 <= XML_REGEXP_OTHER_NA)) ) return(0); break; case XML_REGEXP_NOTNAMECHAR: /* \C */ break; case XML_REGEXP_DECIMAL: /* \d */ /* can't be a letter, mark, separator, punctuation, symbol or other */ if ((type2 == XML_REGEXP_NOTDECIMAL) || (type2 == XML_REGEXP_REALCHAR) || ((type2 >= XML_REGEXP_LETTER) && (type2 <= XML_REGEXP_LETTER_OTHERS)) || ((type2 >= XML_REGEXP_MARK) && (type2 <= XML_REGEXP_MARK_ENCLOSING)) || ((type2 >= XML_REGEXP_PUNCT) && (type2 <= XML_REGEXP_PUNCT_OTHERS)) || ((type2 >= XML_REGEXP_SEPAR) && (type2 <= XML_REGEXP_SEPAR_PARA)) || ((type2 >= XML_REGEXP_SYMBOL) && (type2 <= XML_REGEXP_SYMBOL_OTHERS)) || ((type2 >= XML_REGEXP_OTHER) && (type2 <= XML_REGEXP_OTHER_NA)) )return(0); break; case XML_REGEXP_NOTDECIMAL: /* \D */ break; case XML_REGEXP_REALCHAR: /* \w */ /* can't be a mark, separator, punctuation, symbol or other */ if ((type2 == XML_REGEXP_NOTDECIMAL) || ((type2 >= XML_REGEXP_MARK) && (type2 <= XML_REGEXP_MARK_ENCLOSING)) || ((type2 >= XML_REGEXP_PUNCT) && (type2 <= XML_REGEXP_PUNCT_OTHERS)) || ((type2 >= XML_REGEXP_SEPAR) && (type2 <= XML_REGEXP_SEPAR_PARA)) || ((type2 >= XML_REGEXP_SYMBOL) && (type2 <= XML_REGEXP_SYMBOL_OTHERS)) || ((type2 >= XML_REGEXP_OTHER) && (type2 <= XML_REGEXP_OTHER_NA)) )return(0); break; case XML_REGEXP_NOTREALCHAR: /* \W */ break; /* * at that point we know both type 1 and type2 are from * character categories are ordered and are different, * it becomes simple because this is a partition */ case XML_REGEXP_LETTER: if (type2 <= XML_REGEXP_LETTER_OTHERS) return(1); return(0); case XML_REGEXP_LETTER_UPPERCASE: case XML_REGEXP_LETTER_LOWERCASE: case XML_REGEXP_LETTER_TITLECASE: case XML_REGEXP_LETTER_MODIFIER: case XML_REGEXP_LETTER_OTHERS: return(0); case XML_REGEXP_MARK: if (type2 <= XML_REGEXP_MARK_ENCLOSING) return(1); return(0); case XML_REGEXP_MARK_NONSPACING: case XML_REGEXP_MARK_SPACECOMBINING: case XML_REGEXP_MARK_ENCLOSING: return(0); case XML_REGEXP_NUMBER: if (type2 <= XML_REGEXP_NUMBER_OTHERS) return(1); return(0); case XML_REGEXP_NUMBER_DECIMAL: case XML_REGEXP_NUMBER_LETTER: case XML_REGEXP_NUMBER_OTHERS: return(0); case XML_REGEXP_PUNCT: if (type2 <= XML_REGEXP_PUNCT_OTHERS) return(1); return(0); case XML_REGEXP_PUNCT_CONNECTOR: case XML_REGEXP_PUNCT_DASH: case XML_REGEXP_PUNCT_OPEN: case XML_REGEXP_PUNCT_CLOSE: case XML_REGEXP_PUNCT_INITQUOTE: case XML_REGEXP_PUNCT_FINQUOTE: case XML_REGEXP_PUNCT_OTHERS: return(0); case XML_REGEXP_SEPAR: if (type2 <= XML_REGEXP_SEPAR_PARA) return(1); return(0); case XML_REGEXP_SEPAR_SPACE: case XML_REGEXP_SEPAR_LINE: case XML_REGEXP_SEPAR_PARA: return(0); case XML_REGEXP_SYMBOL: if (type2 <= XML_REGEXP_SYMBOL_OTHERS) return(1); return(0); case XML_REGEXP_SYMBOL_MATH: case XML_REGEXP_SYMBOL_CURRENCY: case XML_REGEXP_SYMBOL_MODIFIER: case XML_REGEXP_SYMBOL_OTHERS: return(0); case XML_REGEXP_OTHER: if (type2 <= XML_REGEXP_OTHER_NA) return(1); return(0); case XML_REGEXP_OTHER_CONTROL: case XML_REGEXP_OTHER_FORMAT: case XML_REGEXP_OTHER_PRIVATE: case XML_REGEXP_OTHER_NA: return(0); default: break; } return(1); } /** * xmlFAEqualAtoms: * @atom1: an atom * @atom2: an atom * @deep: if not set only compare string pointers * * Compares two atoms to check whether they are the same exactly * this is used to remove equivalent transitions * * Returns 1 if same and 0 otherwise */ static int xmlFAEqualAtoms(xmlRegAtomPtr atom1, xmlRegAtomPtr atom2, int deep) { int ret = 0; if (atom1 == atom2) return(1); if ((atom1 == NULL) || (atom2 == NULL)) return(0); if (atom1->type != atom2->type) return(0); switch (atom1->type) { case XML_REGEXP_EPSILON: ret = 0; break; case XML_REGEXP_STRING: if (!deep) ret = (atom1->valuep == atom2->valuep); else ret = xmlStrEqual((xmlChar *)atom1->valuep, (xmlChar *)atom2->valuep); break; case XML_REGEXP_CHARVAL: ret = (atom1->codepoint == atom2->codepoint); break; case XML_REGEXP_RANGES: /* too hard to do in the general case */ ret = 0; default: break; } return(ret); } /** * xmlFACompareAtoms: * @atom1: an atom * @atom2: an atom * @deep: if not set only compare string pointers * * Compares two atoms to check whether they intersect in some ways, * this is used by xmlFAComputesDeterminism and xmlFARecurseDeterminism only * * Returns 1 if yes and 0 otherwise */ static int xmlFACompareAtoms(xmlRegAtomPtr atom1, xmlRegAtomPtr atom2, int deep) { int ret = 1; if (atom1 == atom2) return(1); if ((atom1 == NULL) || (atom2 == NULL)) return(0); if ((atom1->type == XML_REGEXP_ANYCHAR) || (atom2->type == XML_REGEXP_ANYCHAR)) return(1); if (atom1->type > atom2->type) { xmlRegAtomPtr tmp; tmp = atom1; atom1 = atom2; atom2 = tmp; } if (atom1->type != atom2->type) { ret = xmlFACompareAtomTypes(atom1->type, atom2->type); /* if they can't intersect at the type level break now */ if (ret == 0) return(0); } switch (atom1->type) { case XML_REGEXP_STRING: if (!deep) ret = (atom1->valuep != atom2->valuep); else { xmlChar *val1 = (xmlChar *)atom1->valuep; xmlChar *val2 = (xmlChar *)atom2->valuep; int compound1 = (xmlStrchr(val1, '|') != NULL); int compound2 = (xmlStrchr(val2, '|') != NULL); /* Ignore negative match flag for ##other namespaces */ if (compound1 != compound2) return(0); ret = xmlRegStrEqualWildcard(val1, val2); } break; case XML_REGEXP_EPSILON: goto not_determinist; case XML_REGEXP_CHARVAL: if (atom2->type == XML_REGEXP_CHARVAL) { ret = (atom1->codepoint == atom2->codepoint); } else { ret = xmlRegCheckCharacter(atom2, atom1->codepoint); if (ret < 0) ret = 1; } break; case XML_REGEXP_RANGES: if (atom2->type == XML_REGEXP_RANGES) { int i, j, res; xmlRegRangePtr r1, r2; /* * need to check that none of the ranges eventually matches */ for (i = 0;i < atom1->nbRanges;i++) { for (j = 0;j < atom2->nbRanges;j++) { r1 = atom1->ranges[i]; r2 = atom2->ranges[j]; res = xmlFACompareRanges(r1, r2); if (res == 1) { ret = 1; goto done; } } } ret = 0; } break; default: goto not_determinist; } done: if (atom1->neg != atom2->neg) { ret = !ret; } if (ret == 0) return(0); not_determinist: return(1); } /** * xmlFARecurseDeterminism: * @ctxt: a regexp parser context * * Check whether the associated regexp is determinist, * should be called after xmlFAEliminateEpsilonTransitions() * */ static int xmlFARecurseDeterminism(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state, int fromnr, int tonr, xmlRegAtomPtr atom) { int ret = 1; int res; int transnr, nbTrans; xmlRegTransPtr t1; int deep = 1; if (state == NULL) return(ret); if (state->markd == XML_REGEXP_MARK_VISITED) return(ret); if (ctxt->flags & AM_AUTOMATA_RNG) deep = 0; /* * don't recurse on transitions potentially added in the course of * the elimination. */ nbTrans = state->nbTrans; for (transnr = 0;transnr < nbTrans;transnr++) { t1 = &(state->trans[transnr]); /* * check transitions conflicting with the one looked at */ if ((t1->to < 0) || (t1->to == fromnr)) continue; if (t1->atom == NULL) { state->markd = XML_REGEXP_MARK_VISITED; res = xmlFARecurseDeterminism(ctxt, ctxt->states[t1->to], fromnr, tonr, atom); if (res == 0) { ret = 0; /* t1->nd = 1; */ } continue; } if (xmlFACompareAtoms(t1->atom, atom, deep)) { /* Treat equal transitions as deterministic. */ if ((t1->to != tonr) || (!xmlFAEqualAtoms(t1->atom, atom, deep))) ret = 0; /* mark the transition as non-deterministic */ t1->nd = 1; } } return(ret); } /** * xmlFAFinishRecurseDeterminism: * @ctxt: a regexp parser context * * Reset flags after checking determinism. */ static void xmlFAFinishRecurseDeterminism(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state) { int transnr, nbTrans; if (state == NULL) return; if (state->markd != XML_REGEXP_MARK_VISITED) return; state->markd = 0; nbTrans = state->nbTrans; for (transnr = 0; transnr < nbTrans; transnr++) { xmlRegTransPtr t1 = &state->trans[transnr]; if ((t1->atom == NULL) && (t1->to >= 0)) xmlFAFinishRecurseDeterminism(ctxt, ctxt->states[t1->to]); } } /** * xmlFAComputesDeterminism: * @ctxt: a regexp parser context * * Check whether the associated regexp is determinist, * should be called after xmlFAEliminateEpsilonTransitions() * */ static int xmlFAComputesDeterminism(xmlRegParserCtxtPtr ctxt) { int statenr, transnr; xmlRegStatePtr state; xmlRegTransPtr t1, t2, last; int i; int ret = 1; int deep = 1; if (ctxt->determinist != -1) return(ctxt->determinist); if (ctxt->flags & AM_AUTOMATA_RNG) deep = 0; /* * First cleanup the automata removing cancelled transitions */ for (statenr = 0;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if (state == NULL) continue; if (state->nbTrans < 2) continue; for (transnr = 0;transnr < state->nbTrans;transnr++) { t1 = &(state->trans[transnr]); /* * Determinism checks in case of counted or all transitions * will have to be handled separately */ if (t1->atom == NULL) { /* t1->nd = 1; */ continue; } if (t1->to < 0) /* eliminated */ continue; for (i = 0;i < transnr;i++) { t2 = &(state->trans[i]); if (t2->to < 0) /* eliminated */ continue; if (t2->atom != NULL) { if (t1->to == t2->to) { /* * Here we use deep because we want to keep the * transitions which indicate a conflict */ if (xmlFAEqualAtoms(t1->atom, t2->atom, deep) && (t1->counter == t2->counter) && (t1->count == t2->count)) t2->to = -1; /* eliminated */ } } } } } /* * Check for all states that there aren't 2 transitions * with the same atom and a different target. */ for (statenr = 0;statenr < ctxt->nbStates;statenr++) { state = ctxt->states[statenr]; if (state == NULL) continue; if (state->nbTrans < 2) continue; last = NULL; for (transnr = 0;transnr < state->nbTrans;transnr++) { t1 = &(state->trans[transnr]); /* * Determinism checks in case of counted or all transitions * will have to be handled separately */ if (t1->atom == NULL) { continue; } if (t1->to < 0) /* eliminated */ continue; for (i = 0;i < transnr;i++) { t2 = &(state->trans[i]); if (t2->to < 0) /* eliminated */ continue; if (t2->atom != NULL) { /* * But here we don't use deep because we want to * find transitions which indicate a conflict */ if (xmlFACompareAtoms(t1->atom, t2->atom, 1)) { /* * Treat equal counter transitions that couldn't be * eliminated as deterministic. */ if ((t1->to != t2->to) || (t1->counter == t2->counter) || (!xmlFAEqualAtoms(t1->atom, t2->atom, deep))) ret = 0; /* mark the transitions as non-deterministic ones */ t1->nd = 1; t2->nd = 1; last = t1; } } else { int res; /* * do the closure in case of remaining specific * epsilon transitions like choices or all */ res = xmlFARecurseDeterminism(ctxt, ctxt->states[t2->to], statenr, t1->to, t1->atom); xmlFAFinishRecurseDeterminism(ctxt, ctxt->states[t2->to]); /* don't shortcut the computation so all non deterministic transition get marked down if (ret == 0) return(0); */ if (res == 0) { t1->nd = 1; /* t2->nd = 1; */ last = t1; ret = 0; } } } /* don't shortcut the computation so all non deterministic transition get marked down if (ret == 0) break; */ } /* * mark specifically the last non-deterministic transition * from a state since there is no need to set-up rollback * from it */ if (last != NULL) { last->nd = 2; } /* don't shortcut the computation so all non deterministic transition get marked down if (ret == 0) break; */ } ctxt->determinist = ret; return(ret); } /************************************************************************ * * * Routines to check input against transition atoms * * * ************************************************************************/ static int xmlRegCheckCharacterRange(xmlRegAtomType type, int codepoint, int neg, int start, int end, const xmlChar *blockName) { int ret = 0; switch (type) { case XML_REGEXP_STRING: case XML_REGEXP_SUBREG: case XML_REGEXP_RANGES: case XML_REGEXP_EPSILON: return(-1); case XML_REGEXP_ANYCHAR: ret = ((codepoint != '\n') && (codepoint != '\r')); break; case XML_REGEXP_CHARVAL: ret = ((codepoint >= start) && (codepoint <= end)); break; case XML_REGEXP_NOTSPACE: neg = !neg; /* Falls through. */ case XML_REGEXP_ANYSPACE: ret = ((codepoint == '\n') || (codepoint == '\r') || (codepoint == '\t') || (codepoint == ' ')); break; case XML_REGEXP_NOTINITNAME: neg = !neg; /* Falls through. */ case XML_REGEXP_INITNAME: ret = (IS_LETTER(codepoint) || (codepoint == '_') || (codepoint == ':')); break; case XML_REGEXP_NOTNAMECHAR: neg = !neg; /* Falls through. */ case XML_REGEXP_NAMECHAR: ret = (IS_LETTER(codepoint) || IS_DIGIT(codepoint) || (codepoint == '.') || (codepoint == '-') || (codepoint == '_') || (codepoint == ':') || IS_COMBINING(codepoint) || IS_EXTENDER(codepoint)); break; case XML_REGEXP_NOTDECIMAL: neg = !neg; /* Falls through. */ case XML_REGEXP_DECIMAL: ret = xmlUCSIsCatNd(codepoint); break; case XML_REGEXP_REALCHAR: neg = !neg; /* Falls through. */ case XML_REGEXP_NOTREALCHAR: ret = xmlUCSIsCatP(codepoint); if (ret == 0) ret = xmlUCSIsCatZ(codepoint); if (ret == 0) ret = xmlUCSIsCatC(codepoint); break; case XML_REGEXP_LETTER: ret = xmlUCSIsCatL(codepoint); break; case XML_REGEXP_LETTER_UPPERCASE: ret = xmlUCSIsCatLu(codepoint); break; case XML_REGEXP_LETTER_LOWERCASE: ret = xmlUCSIsCatLl(codepoint); break; case XML_REGEXP_LETTER_TITLECASE: ret = xmlUCSIsCatLt(codepoint); break; case XML_REGEXP_LETTER_MODIFIER: ret = xmlUCSIsCatLm(codepoint); break; case XML_REGEXP_LETTER_OTHERS: ret = xmlUCSIsCatLo(codepoint); break; case XML_REGEXP_MARK: ret = xmlUCSIsCatM(codepoint); break; case XML_REGEXP_MARK_NONSPACING: ret = xmlUCSIsCatMn(codepoint); break; case XML_REGEXP_MARK_SPACECOMBINING: ret = xmlUCSIsCatMc(codepoint); break; case XML_REGEXP_MARK_ENCLOSING: ret = xmlUCSIsCatMe(codepoint); break; case XML_REGEXP_NUMBER: ret = xmlUCSIsCatN(codepoint); break; case XML_REGEXP_NUMBER_DECIMAL: ret = xmlUCSIsCatNd(codepoint); break; case XML_REGEXP_NUMBER_LETTER: ret = xmlUCSIsCatNl(codepoint); break; case XML_REGEXP_NUMBER_OTHERS: ret = xmlUCSIsCatNo(codepoint); break; case XML_REGEXP_PUNCT: ret = xmlUCSIsCatP(codepoint); break; case XML_REGEXP_PUNCT_CONNECTOR: ret = xmlUCSIsCatPc(codepoint); break; case XML_REGEXP_PUNCT_DASH: ret = xmlUCSIsCatPd(codepoint); break; case XML_REGEXP_PUNCT_OPEN: ret = xmlUCSIsCatPs(codepoint); break; case XML_REGEXP_PUNCT_CLOSE: ret = xmlUCSIsCatPe(codepoint); break; case XML_REGEXP_PUNCT_INITQUOTE: ret = xmlUCSIsCatPi(codepoint); break; case XML_REGEXP_PUNCT_FINQUOTE: ret = xmlUCSIsCatPf(codepoint); break; case XML_REGEXP_PUNCT_OTHERS: ret = xmlUCSIsCatPo(codepoint); break; case XML_REGEXP_SEPAR: ret = xmlUCSIsCatZ(codepoint); break; case XML_REGEXP_SEPAR_SPACE: ret = xmlUCSIsCatZs(codepoint); break; case XML_REGEXP_SEPAR_LINE: ret = xmlUCSIsCatZl(codepoint); break; case XML_REGEXP_SEPAR_PARA: ret = xmlUCSIsCatZp(codepoint); break; case XML_REGEXP_SYMBOL: ret = xmlUCSIsCatS(codepoint); break; case XML_REGEXP_SYMBOL_MATH: ret = xmlUCSIsCatSm(codepoint); break; case XML_REGEXP_SYMBOL_CURRENCY: ret = xmlUCSIsCatSc(codepoint); break; case XML_REGEXP_SYMBOL_MODIFIER: ret = xmlUCSIsCatSk(codepoint); break; case XML_REGEXP_SYMBOL_OTHERS: ret = xmlUCSIsCatSo(codepoint); break; case XML_REGEXP_OTHER: ret = xmlUCSIsCatC(codepoint); break; case XML_REGEXP_OTHER_CONTROL: ret = xmlUCSIsCatCc(codepoint); break; case XML_REGEXP_OTHER_FORMAT: ret = xmlUCSIsCatCf(codepoint); break; case XML_REGEXP_OTHER_PRIVATE: ret = xmlUCSIsCatCo(codepoint); break; case XML_REGEXP_OTHER_NA: /* ret = xmlUCSIsCatCn(codepoint); */ /* Seems it doesn't exist anymore in recent Unicode releases */ ret = 0; break; case XML_REGEXP_BLOCK_NAME: ret = xmlUCSIsBlock(codepoint, (const char *) blockName); break; } if (neg) return(!ret); return(ret); } static int xmlRegCheckCharacter(xmlRegAtomPtr atom, int codepoint) { int i, ret = 0; xmlRegRangePtr range; if ((atom == NULL) || (!IS_CHAR(codepoint))) return(-1); switch (atom->type) { case XML_REGEXP_SUBREG: case XML_REGEXP_EPSILON: return(-1); case XML_REGEXP_CHARVAL: return(codepoint == atom->codepoint); case XML_REGEXP_RANGES: { int accept = 0; for (i = 0;i < atom->nbRanges;i++) { range = atom->ranges[i]; if (range->neg == 2) { ret = xmlRegCheckCharacterRange(range->type, codepoint, 0, range->start, range->end, range->blockName); if (ret != 0) return(0); /* excluded char */ } else if (range->neg) { ret = xmlRegCheckCharacterRange(range->type, codepoint, 0, range->start, range->end, range->blockName); if (ret == 0) accept = 1; else return(0); } else { ret = xmlRegCheckCharacterRange(range->type, codepoint, 0, range->start, range->end, range->blockName); if (ret != 0) accept = 1; /* might still be excluded */ } } return(accept); } case XML_REGEXP_STRING: printf("TODO: XML_REGEXP_STRING\n"); return(-1); case XML_REGEXP_ANYCHAR: case XML_REGEXP_ANYSPACE: case XML_REGEXP_NOTSPACE: case XML_REGEXP_INITNAME: case XML_REGEXP_NOTINITNAME: case XML_REGEXP_NAMECHAR: case XML_REGEXP_NOTNAMECHAR: case XML_REGEXP_DECIMAL: case XML_REGEXP_NOTDECIMAL: case XML_REGEXP_REALCHAR: case XML_REGEXP_NOTREALCHAR: case XML_REGEXP_LETTER: case XML_REGEXP_LETTER_UPPERCASE: case XML_REGEXP_LETTER_LOWERCASE: case XML_REGEXP_LETTER_TITLECASE: case XML_REGEXP_LETTER_MODIFIER: case XML_REGEXP_LETTER_OTHERS: case XML_REGEXP_MARK: case XML_REGEXP_MARK_NONSPACING: case XML_REGEXP_MARK_SPACECOMBINING: case XML_REGEXP_MARK_ENCLOSING: case XML_REGEXP_NUMBER: case XML_REGEXP_NUMBER_DECIMAL: case XML_REGEXP_NUMBER_LETTER: case XML_REGEXP_NUMBER_OTHERS: case XML_REGEXP_PUNCT: case XML_REGEXP_PUNCT_CONNECTOR: case XML_REGEXP_PUNCT_DASH: case XML_REGEXP_PUNCT_OPEN: case XML_REGEXP_PUNCT_CLOSE: case XML_REGEXP_PUNCT_INITQUOTE: case XML_REGEXP_PUNCT_FINQUOTE: case XML_REGEXP_PUNCT_OTHERS: case XML_REGEXP_SEPAR: case XML_REGEXP_SEPAR_SPACE: case XML_REGEXP_SEPAR_LINE: case XML_REGEXP_SEPAR_PARA: case XML_REGEXP_SYMBOL: case XML_REGEXP_SYMBOL_MATH: case XML_REGEXP_SYMBOL_CURRENCY: case XML_REGEXP_SYMBOL_MODIFIER: case XML_REGEXP_SYMBOL_OTHERS: case XML_REGEXP_OTHER: case XML_REGEXP_OTHER_CONTROL: case XML_REGEXP_OTHER_FORMAT: case XML_REGEXP_OTHER_PRIVATE: case XML_REGEXP_OTHER_NA: case XML_REGEXP_BLOCK_NAME: ret = xmlRegCheckCharacterRange(atom->type, codepoint, 0, 0, 0, (const xmlChar *)atom->valuep); if (atom->neg) ret = !ret; break; } return(ret); } /************************************************************************ * * * Saving and restoring state of an execution context * * * ************************************************************************/ static void xmlFARegExecSave(xmlRegExecCtxtPtr exec) { #ifdef MAX_PUSH if (exec->nbPush > MAX_PUSH) { return; } exec->nbPush++; #endif if (exec->maxRollbacks == 0) { exec->maxRollbacks = 4; exec->rollbacks = (xmlRegExecRollback *) xmlMalloc(exec->maxRollbacks * sizeof(xmlRegExecRollback)); if (exec->rollbacks == NULL) { xmlRegexpErrMemory(NULL, "saving regexp"); exec->maxRollbacks = 0; return; } memset(exec->rollbacks, 0, exec->maxRollbacks * sizeof(xmlRegExecRollback)); } else if (exec->nbRollbacks >= exec->maxRollbacks) { xmlRegExecRollback *tmp; int len = exec->maxRollbacks; exec->maxRollbacks *= 2; tmp = (xmlRegExecRollback *) xmlRealloc(exec->rollbacks, exec->maxRollbacks * sizeof(xmlRegExecRollback)); if (tmp == NULL) { xmlRegexpErrMemory(NULL, "saving regexp"); exec->maxRollbacks /= 2; return; } exec->rollbacks = tmp; tmp = &exec->rollbacks[len]; memset(tmp, 0, (exec->maxRollbacks - len) * sizeof(xmlRegExecRollback)); } exec->rollbacks[exec->nbRollbacks].state = exec->state; exec->rollbacks[exec->nbRollbacks].index = exec->index; exec->rollbacks[exec->nbRollbacks].nextbranch = exec->transno + 1; if (exec->comp->nbCounters > 0) { if (exec->rollbacks[exec->nbRollbacks].counts == NULL) { exec->rollbacks[exec->nbRollbacks].counts = (int *) xmlMalloc(exec->comp->nbCounters * sizeof(int)); if (exec->rollbacks[exec->nbRollbacks].counts == NULL) { xmlRegexpErrMemory(NULL, "saving regexp"); exec->status = -5; return; } } memcpy(exec->rollbacks[exec->nbRollbacks].counts, exec->counts, exec->comp->nbCounters * sizeof(int)); } exec->nbRollbacks++; } static void xmlFARegExecRollBack(xmlRegExecCtxtPtr exec) { if (exec->nbRollbacks <= 0) { exec->status = -1; return; } exec->nbRollbacks--; exec->state = exec->rollbacks[exec->nbRollbacks].state; exec->index = exec->rollbacks[exec->nbRollbacks].index; exec->transno = exec->rollbacks[exec->nbRollbacks].nextbranch; if (exec->comp->nbCounters > 0) { if (exec->rollbacks[exec->nbRollbacks].counts == NULL) { fprintf(stderr, "exec save: allocation failed"); exec->status = -6; return; } if (exec->counts) { memcpy(exec->counts, exec->rollbacks[exec->nbRollbacks].counts, exec->comp->nbCounters * sizeof(int)); } } } /************************************************************************ * * * Verifier, running an input against a compiled regexp * * * ************************************************************************/ static int xmlFARegExec(xmlRegexpPtr comp, const xmlChar *content) { xmlRegExecCtxt execval; xmlRegExecCtxtPtr exec = &execval; int ret, codepoint = 0, len, deter; exec->inputString = content; exec->index = 0; exec->nbPush = 0; exec->determinist = 1; exec->maxRollbacks = 0; exec->nbRollbacks = 0; exec->rollbacks = NULL; exec->status = 0; exec->comp = comp; exec->state = comp->states[0]; exec->transno = 0; exec->transcount = 0; exec->inputStack = NULL; exec->inputStackMax = 0; if (comp->nbCounters > 0) { exec->counts = (int *) xmlMalloc(comp->nbCounters * sizeof(int)); if (exec->counts == NULL) { xmlRegexpErrMemory(NULL, "running regexp"); return(-1); } memset(exec->counts, 0, comp->nbCounters * sizeof(int)); } else exec->counts = NULL; while ((exec->status == 0) && (exec->state != NULL) && ((exec->inputString[exec->index] != 0) || ((exec->state != NULL) && (exec->state->type != XML_REGEXP_FINAL_STATE)))) { xmlRegTransPtr trans; xmlRegAtomPtr atom; /* * If end of input on non-terminal state, rollback, however we may * still have epsilon like transition for counted transitions * on counters, in that case don't break too early. Additionally, * if we are working on a range like "AB{0,2}", where B is not present, * we don't want to break. */ len = 1; if ((exec->inputString[exec->index] == 0) && (exec->counts == NULL)) { /* * if there is a transition, we must check if * atom allows minOccurs of 0 */ if (exec->transno < exec->state->nbTrans) { trans = &exec->state->trans[exec->transno]; if (trans->to >=0) { atom = trans->atom; if (!((atom->min == 0) && (atom->max > 0))) goto rollback; } } else goto rollback; } exec->transcount = 0; for (;exec->transno < exec->state->nbTrans;exec->transno++) { trans = &exec->state->trans[exec->transno]; if (trans->to < 0) continue; atom = trans->atom; ret = 0; deter = 1; if (trans->count >= 0) { int count; xmlRegCounterPtr counter; if (exec->counts == NULL) { exec->status = -1; goto error; } /* * A counted transition. */ count = exec->counts[trans->count]; counter = &exec->comp->counters[trans->count]; ret = ((count >= counter->min) && (count <= counter->max)); if ((ret) && (counter->min != counter->max)) deter = 0; } else if (atom == NULL) { fprintf(stderr, "epsilon transition left at runtime\n"); exec->status = -2; break; } else if (exec->inputString[exec->index] != 0) { codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len); ret = xmlRegCheckCharacter(atom, codepoint); if ((ret == 1) && (atom->min >= 0) && (atom->max > 0)) { xmlRegStatePtr to = comp->states[trans->to]; /* * this is a multiple input sequence * If there is a counter associated increment it now. * do not increment if the counter is already over the * maximum limit in which case get to next transition */ if (trans->counter >= 0) { xmlRegCounterPtr counter; if ((exec->counts == NULL) || (exec->comp == NULL) || (exec->comp->counters == NULL)) { exec->status = -1; goto error; } counter = &exec->comp->counters[trans->counter]; if (exec->counts[trans->counter] >= counter->max) continue; /* for loop on transitions */ } /* Save before incrementing */ if (exec->state->nbTrans > exec->transno + 1) { xmlFARegExecSave(exec); } if (trans->counter >= 0) { exec->counts[trans->counter]++; } exec->transcount = 1; do { /* * Try to progress as much as possible on the input */ if (exec->transcount == atom->max) { break; } exec->index += len; /* * End of input: stop here */ if (exec->inputString[exec->index] == 0) { exec->index -= len; break; } if (exec->transcount >= atom->min) { int transno = exec->transno; xmlRegStatePtr state = exec->state; /* * The transition is acceptable save it */ exec->transno = -1; /* trick */ exec->state = to; xmlFARegExecSave(exec); exec->transno = transno; exec->state = state; } codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len); ret = xmlRegCheckCharacter(atom, codepoint); exec->transcount++; } while (ret == 1); if (exec->transcount < atom->min) ret = 0; /* * If the last check failed but one transition was found * possible, rollback */ if (ret < 0) ret = 0; if (ret == 0) { goto rollback; } if (trans->counter >= 0) { if (exec->counts == NULL) { exec->status = -1; goto error; } exec->counts[trans->counter]--; } } else if ((ret == 0) && (atom->min == 0) && (atom->max > 0)) { /* * we don't match on the codepoint, but minOccurs of 0 * says that's ok. Setting len to 0 inhibits stepping * over the codepoint. */ exec->transcount = 1; len = 0; ret = 1; } } else if ((atom->min == 0) && (atom->max > 0)) { /* another spot to match when minOccurs is 0 */ exec->transcount = 1; len = 0; ret = 1; } if (ret == 1) { if ((trans->nd == 1) || ((trans->count >= 0) && (deter == 0) && (exec->state->nbTrans > exec->transno + 1))) { xmlFARegExecSave(exec); } if (trans->counter >= 0) { xmlRegCounterPtr counter; /* make sure we don't go over the counter maximum value */ if ((exec->counts == NULL) || (exec->comp == NULL) || (exec->comp->counters == NULL)) { exec->status = -1; goto error; } counter = &exec->comp->counters[trans->counter]; if (exec->counts[trans->counter] >= counter->max) continue; /* for loop on transitions */ exec->counts[trans->counter]++; } if ((trans->count >= 0) && (trans->count < REGEXP_ALL_COUNTER)) { if (exec->counts == NULL) { exec->status = -1; goto error; } exec->counts[trans->count] = 0; } exec->state = comp->states[trans->to]; exec->transno = 0; if (trans->atom != NULL) { exec->index += len; } goto progress; } else if (ret < 0) { exec->status = -4; break; } } if ((exec->transno != 0) || (exec->state->nbTrans == 0)) { rollback: /* * Failed to find a way out */ exec->determinist = 0; xmlFARegExecRollBack(exec); } progress: continue; } error: if (exec->rollbacks != NULL) { if (exec->counts != NULL) { int i; for (i = 0;i < exec->maxRollbacks;i++) if (exec->rollbacks[i].counts != NULL) xmlFree(exec->rollbacks[i].counts); } xmlFree(exec->rollbacks); } if (exec->state == NULL) return(-1); if (exec->counts != NULL) xmlFree(exec->counts); if (exec->status == 0) return(1); if (exec->status == -1) { if (exec->nbPush > MAX_PUSH) return(-1); return(0); } return(exec->status); } /************************************************************************ * * * Progressive interface to the verifier one atom at a time * * * ************************************************************************/ /** * xmlRegNewExecCtxt: * @comp: a precompiled regular expression * @callback: a callback function used for handling progresses in the * automata matching phase * @data: the context data associated to the callback in this context * * Build a context used for progressive evaluation of a regexp. * * Returns the new context */ xmlRegExecCtxtPtr xmlRegNewExecCtxt(xmlRegexpPtr comp, xmlRegExecCallbacks callback, void *data) { xmlRegExecCtxtPtr exec; if (comp == NULL) return(NULL); if ((comp->compact == NULL) && (comp->states == NULL)) return(NULL); exec = (xmlRegExecCtxtPtr) xmlMalloc(sizeof(xmlRegExecCtxt)); if (exec == NULL) { xmlRegexpErrMemory(NULL, "creating execution context"); return(NULL); } memset(exec, 0, sizeof(xmlRegExecCtxt)); exec->inputString = NULL; exec->index = 0; exec->determinist = 1; exec->maxRollbacks = 0; exec->nbRollbacks = 0; exec->rollbacks = NULL; exec->status = 0; exec->comp = comp; if (comp->compact == NULL) exec->state = comp->states[0]; exec->transno = 0; exec->transcount = 0; exec->callback = callback; exec->data = data; if (comp->nbCounters > 0) { /* * For error handling, exec->counts is allocated twice the size * the second half is used to store the data in case of rollback */ exec->counts = (int *) xmlMalloc(comp->nbCounters * sizeof(int) * 2); if (exec->counts == NULL) { xmlRegexpErrMemory(NULL, "creating execution context"); xmlFree(exec); return(NULL); } memset(exec->counts, 0, comp->nbCounters * sizeof(int) * 2); exec->errCounts = &exec->counts[comp->nbCounters]; } else { exec->counts = NULL; exec->errCounts = NULL; } exec->inputStackMax = 0; exec->inputStackNr = 0; exec->inputStack = NULL; exec->errStateNo = -1; exec->errString = NULL; exec->nbPush = 0; return(exec); } /** * xmlRegFreeExecCtxt: * @exec: a regular expression evaluation context * * Free the structures associated to a regular expression evaluation context. */ void xmlRegFreeExecCtxt(xmlRegExecCtxtPtr exec) { if (exec == NULL) return; if (exec->rollbacks != NULL) { if (exec->counts != NULL) { int i; for (i = 0;i < exec->maxRollbacks;i++) if (exec->rollbacks[i].counts != NULL) xmlFree(exec->rollbacks[i].counts); } xmlFree(exec->rollbacks); } if (exec->counts != NULL) xmlFree(exec->counts); if (exec->inputStack != NULL) { int i; for (i = 0;i < exec->inputStackNr;i++) { if (exec->inputStack[i].value != NULL) xmlFree(exec->inputStack[i].value); } xmlFree(exec->inputStack); } if (exec->errString != NULL) xmlFree(exec->errString); xmlFree(exec); } static void xmlFARegExecSaveInputString(xmlRegExecCtxtPtr exec, const xmlChar *value, void *data) { if (exec->inputStackMax == 0) { exec->inputStackMax = 4; exec->inputStack = (xmlRegInputTokenPtr) xmlMalloc(exec->inputStackMax * sizeof(xmlRegInputToken)); if (exec->inputStack == NULL) { xmlRegexpErrMemory(NULL, "pushing input string"); exec->inputStackMax = 0; return; } } else if (exec->inputStackNr + 1 >= exec->inputStackMax) { xmlRegInputTokenPtr tmp; exec->inputStackMax *= 2; tmp = (xmlRegInputTokenPtr) xmlRealloc(exec->inputStack, exec->inputStackMax * sizeof(xmlRegInputToken)); if (tmp == NULL) { xmlRegexpErrMemory(NULL, "pushing input string"); exec->inputStackMax /= 2; return; } exec->inputStack = tmp; } exec->inputStack[exec->inputStackNr].value = xmlStrdup(value); exec->inputStack[exec->inputStackNr].data = data; exec->inputStackNr++; exec->inputStack[exec->inputStackNr].value = NULL; exec->inputStack[exec->inputStackNr].data = NULL; } /** * xmlRegStrEqualWildcard: * @expStr: the string to be evaluated * @valStr: the validation string * * Checks if both strings are equal or have the same content. "*" * can be used as a wildcard in @valStr; "|" is used as a separator of * substrings in both @expStr and @valStr. * * Returns 1 if the comparison is satisfied and the number of substrings * is equal, 0 otherwise. */ static int xmlRegStrEqualWildcard(const xmlChar *expStr, const xmlChar *valStr) { if (expStr == valStr) return(1); if (expStr == NULL) return(0); if (valStr == NULL) return(0); do { /* * Eval if we have a wildcard for the current item. */ if (*expStr != *valStr) { /* if one of them starts with a wildcard make valStr be it */ if (*valStr == '*') { const xmlChar *tmp; tmp = valStr; valStr = expStr; expStr = tmp; } if ((*valStr != 0) && (*expStr != 0) && (*expStr++ == '*')) { do { if (*valStr == XML_REG_STRING_SEPARATOR) break; valStr++; } while (*valStr != 0); continue; } else return(0); } expStr++; valStr++; } while (*valStr != 0); if (*expStr != 0) return (0); else return (1); } /** * xmlRegCompactPushString: * @exec: a regexp execution context * @comp: the precompiled exec with a compact table * @value: a string token input * @data: data associated to the token to reuse in callbacks * * Push one input token in the execution context * * Returns: 1 if the regexp reached a final state, 0 if non-final, and * a negative value in case of error. */ static int xmlRegCompactPushString(xmlRegExecCtxtPtr exec, xmlRegexpPtr comp, const xmlChar *value, void *data) { int state = exec->index; int i, target; if ((comp == NULL) || (comp->compact == NULL) || (comp->stringMap == NULL)) return(-1); if (value == NULL) { /* * are we at a final state ? */ if (comp->compact[state * (comp->nbstrings + 1)] == XML_REGEXP_FINAL_STATE) return(1); return(0); } /* * Examine all outside transitions from current state */ for (i = 0;i < comp->nbstrings;i++) { target = comp->compact[state * (comp->nbstrings + 1) + i + 1]; if ((target > 0) && (target <= comp->nbstates)) { target--; /* to avoid 0 */ if (xmlRegStrEqualWildcard(comp->stringMap[i], value)) { exec->index = target; if ((exec->callback != NULL) && (comp->transdata != NULL)) { exec->callback(exec->data, value, comp->transdata[state * comp->nbstrings + i], data); } if (comp->compact[target * (comp->nbstrings + 1)] == XML_REGEXP_SINK_STATE) goto error; if (comp->compact[target * (comp->nbstrings + 1)] == XML_REGEXP_FINAL_STATE) return(1); return(0); } } } /* * Failed to find an exit transition out from current state for the * current token */ error: if (exec->errString != NULL) xmlFree(exec->errString); exec->errString = xmlStrdup(value); exec->errStateNo = state; exec->status = -1; return(-1); } /** * xmlRegExecPushStringInternal: * @exec: a regexp execution context or NULL to indicate the end * @value: a string token input * @data: data associated to the token to reuse in callbacks * @compound: value was assembled from 2 strings * * Push one input token in the execution context * * Returns: 1 if the regexp reached a final state, 0 if non-final, and * a negative value in case of error. */ static int xmlRegExecPushStringInternal(xmlRegExecCtxtPtr exec, const xmlChar *value, void *data, int compound) { xmlRegTransPtr trans; xmlRegAtomPtr atom; int ret; int final = 0; int progress = 1; if (exec == NULL) return(-1); if (exec->comp == NULL) return(-1); if (exec->status != 0) return(exec->status); if (exec->comp->compact != NULL) return(xmlRegCompactPushString(exec, exec->comp, value, data)); if (value == NULL) { if (exec->state->type == XML_REGEXP_FINAL_STATE) return(1); final = 1; } /* * If we have an active rollback stack push the new value there * and get back to where we were left */ if ((value != NULL) && (exec->inputStackNr > 0)) { xmlFARegExecSaveInputString(exec, value, data); value = exec->inputStack[exec->index].value; data = exec->inputStack[exec->index].data; } while ((exec->status == 0) && ((value != NULL) || ((final == 1) && (exec->state->type != XML_REGEXP_FINAL_STATE)))) { /* * End of input on non-terminal state, rollback, however we may * still have epsilon like transition for counted transitions * on counters, in that case don't break too early. */ if ((value == NULL) && (exec->counts == NULL)) goto rollback; exec->transcount = 0; for (;exec->transno < exec->state->nbTrans;exec->transno++) { trans = &exec->state->trans[exec->transno]; if (trans->to < 0) continue; atom = trans->atom; ret = 0; if (trans->count == REGEXP_ALL_LAX_COUNTER) { int i; int count; xmlRegTransPtr t; xmlRegCounterPtr counter; ret = 0; /* * Check all counted transitions from the current state */ if ((value == NULL) && (final)) { ret = 1; } else if (value != NULL) { for (i = 0;i < exec->state->nbTrans;i++) { t = &exec->state->trans[i]; if ((t->counter < 0) || (t == trans)) continue; counter = &exec->comp->counters[t->counter]; count = exec->counts[t->counter]; if ((count < counter->max) && (t->atom != NULL) && (xmlStrEqual(value, t->atom->valuep))) { ret = 0; break; } if ((count >= counter->min) && (count < counter->max) && (t->atom != NULL) && (xmlStrEqual(value, t->atom->valuep))) { ret = 1; break; } } } } else if (trans->count == REGEXP_ALL_COUNTER) { int i; int count; xmlRegTransPtr t; xmlRegCounterPtr counter; ret = 1; /* * Check all counted transitions from the current state */ for (i = 0;i < exec->state->nbTrans;i++) { t = &exec->state->trans[i]; if ((t->counter < 0) || (t == trans)) continue; counter = &exec->comp->counters[t->counter]; count = exec->counts[t->counter]; if ((count < counter->min) || (count > counter->max)) { ret = 0; break; } } } else if (trans->count >= 0) { int count; xmlRegCounterPtr counter; /* * A counted transition. */ count = exec->counts[trans->count]; counter = &exec->comp->counters[trans->count]; ret = ((count >= counter->min) && (count <= counter->max)); } else if (atom == NULL) { fprintf(stderr, "epsilon transition left at runtime\n"); exec->status = -2; break; } else if (value != NULL) { ret = xmlRegStrEqualWildcard(atom->valuep, value); if (atom->neg) { ret = !ret; if (!compound) ret = 0; } if ((ret == 1) && (trans->counter >= 0)) { xmlRegCounterPtr counter; int count; count = exec->counts[trans->counter]; counter = &exec->comp->counters[trans->counter]; if (count >= counter->max) ret = 0; } if ((ret == 1) && (atom->min > 0) && (atom->max > 0)) { xmlRegStatePtr to = exec->comp->states[trans->to]; /* * this is a multiple input sequence */ if (exec->state->nbTrans > exec->transno + 1) { if (exec->inputStackNr <= 0) { xmlFARegExecSaveInputString(exec, value, data); } xmlFARegExecSave(exec); } exec->transcount = 1; do { /* * Try to progress as much as possible on the input */ if (exec->transcount == atom->max) { break; } exec->index++; value = exec->inputStack[exec->index].value; data = exec->inputStack[exec->index].data; /* * End of input: stop here */ if (value == NULL) { exec->index --; break; } if (exec->transcount >= atom->min) { int transno = exec->transno; xmlRegStatePtr state = exec->state; /* * The transition is acceptable save it */ exec->transno = -1; /* trick */ exec->state = to; if (exec->inputStackNr <= 0) { xmlFARegExecSaveInputString(exec, value, data); } xmlFARegExecSave(exec); exec->transno = transno; exec->state = state; } ret = xmlStrEqual(value, atom->valuep); exec->transcount++; } while (ret == 1); if (exec->transcount < atom->min) ret = 0; /* * If the last check failed but one transition was found * possible, rollback */ if (ret < 0) ret = 0; if (ret == 0) { goto rollback; } } } if (ret == 1) { if ((exec->callback != NULL) && (atom != NULL) && (data != NULL)) { exec->callback(exec->data, atom->valuep, atom->data, data); } if (exec->state->nbTrans > exec->transno + 1) { if (exec->inputStackNr <= 0) { xmlFARegExecSaveInputString(exec, value, data); } xmlFARegExecSave(exec); } if (trans->counter >= 0) { exec->counts[trans->counter]++; } if ((trans->count >= 0) && (trans->count < REGEXP_ALL_COUNTER)) { exec->counts[trans->count] = 0; } if ((exec->comp->states[trans->to] != NULL) && (exec->comp->states[trans->to]->type == XML_REGEXP_SINK_STATE)) { /* * entering a sink state, save the current state as error * state. */ if (exec->errString != NULL) xmlFree(exec->errString); exec->errString = xmlStrdup(value); exec->errState = exec->state; memcpy(exec->errCounts, exec->counts, exec->comp->nbCounters * sizeof(int)); } exec->state = exec->comp->states[trans->to]; exec->transno = 0; if (trans->atom != NULL) { if (exec->inputStack != NULL) { exec->index++; if (exec->index < exec->inputStackNr) { value = exec->inputStack[exec->index].value; data = exec->inputStack[exec->index].data; } else { value = NULL; data = NULL; } } else { value = NULL; data = NULL; } } goto progress; } else if (ret < 0) { exec->status = -4; break; } } if ((exec->transno != 0) || (exec->state->nbTrans == 0)) { rollback: /* * if we didn't yet rollback on the current input * store the current state as the error state. */ if ((progress) && (exec->state != NULL) && (exec->state->type != XML_REGEXP_SINK_STATE)) { progress = 0; if (exec->errString != NULL) xmlFree(exec->errString); exec->errString = xmlStrdup(value); exec->errState = exec->state; if (exec->comp->nbCounters) memcpy(exec->errCounts, exec->counts, exec->comp->nbCounters * sizeof(int)); } /* * Failed to find a way out */ exec->determinist = 0; xmlFARegExecRollBack(exec); if ((exec->inputStack != NULL ) && (exec->status == 0)) { value = exec->inputStack[exec->index].value; data = exec->inputStack[exec->index].data; } } continue; progress: progress = 1; continue; } if (exec->status == 0) { return(exec->state->type == XML_REGEXP_FINAL_STATE); } return(exec->status); } /** * xmlRegExecPushString: * @exec: a regexp execution context or NULL to indicate the end * @value: a string token input * @data: data associated to the token to reuse in callbacks * * Push one input token in the execution context * * Returns: 1 if the regexp reached a final state, 0 if non-final, and * a negative value in case of error. */ int xmlRegExecPushString(xmlRegExecCtxtPtr exec, const xmlChar *value, void *data) { return(xmlRegExecPushStringInternal(exec, value, data, 0)); } /** * xmlRegExecPushString2: * @exec: a regexp execution context or NULL to indicate the end * @value: the first string token input * @value2: the second string token input * @data: data associated to the token to reuse in callbacks * * Push one input token in the execution context * * Returns: 1 if the regexp reached a final state, 0 if non-final, and * a negative value in case of error. */ int xmlRegExecPushString2(xmlRegExecCtxtPtr exec, const xmlChar *value, const xmlChar *value2, void *data) { xmlChar buf[150]; int lenn, lenp, ret; xmlChar *str; if (exec == NULL) return(-1); if (exec->comp == NULL) return(-1); if (exec->status != 0) return(exec->status); if (value2 == NULL) return(xmlRegExecPushString(exec, value, data)); lenn = strlen((char *) value2); lenp = strlen((char *) value); if (150 < lenn + lenp + 2) { str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2); if (str == NULL) { exec->status = -1; return(-1); } } else { str = buf; } memcpy(&str[0], value, lenp); str[lenp] = XML_REG_STRING_SEPARATOR; memcpy(&str[lenp + 1], value2, lenn); str[lenn + lenp + 1] = 0; if (exec->comp->compact != NULL) ret = xmlRegCompactPushString(exec, exec->comp, str, data); else ret = xmlRegExecPushStringInternal(exec, str, data, 1); if (str != buf) xmlFree(str); return(ret); } /** * xmlRegExecGetValues: * @exec: a regexp execution context * @err: error extraction or normal one * @nbval: pointer to the number of accepted values IN/OUT * @nbneg: return number of negative transitions * @values: pointer to the array of acceptable values * @terminal: return value if this was a terminal state * * Extract information from the regexp execution, internal routine to * implement xmlRegExecNextValues() and xmlRegExecErrInfo() * * Returns: 0 in case of success or -1 in case of error. */ static int xmlRegExecGetValues(xmlRegExecCtxtPtr exec, int err, int *nbval, int *nbneg, xmlChar **values, int *terminal) { int maxval; int nb = 0; if ((exec == NULL) || (nbval == NULL) || (nbneg == NULL) || (values == NULL) || (*nbval <= 0)) return(-1); maxval = *nbval; *nbval = 0; *nbneg = 0; if ((exec->comp != NULL) && (exec->comp->compact != NULL)) { xmlRegexpPtr comp; int target, i, state; comp = exec->comp; if (err) { if (exec->errStateNo == -1) return(-1); state = exec->errStateNo; } else { state = exec->index; } if (terminal != NULL) { if (comp->compact[state * (comp->nbstrings + 1)] == XML_REGEXP_FINAL_STATE) *terminal = 1; else *terminal = 0; } for (i = 0;(i < comp->nbstrings) && (nb < maxval);i++) { target = comp->compact[state * (comp->nbstrings + 1) + i + 1]; if ((target > 0) && (target <= comp->nbstates) && (comp->compact[(target - 1) * (comp->nbstrings + 1)] != XML_REGEXP_SINK_STATE)) { values[nb++] = comp->stringMap[i]; (*nbval)++; } } for (i = 0;(i < comp->nbstrings) && (nb < maxval);i++) { target = comp->compact[state * (comp->nbstrings + 1) + i + 1]; if ((target > 0) && (target <= comp->nbstates) && (comp->compact[(target - 1) * (comp->nbstrings + 1)] == XML_REGEXP_SINK_STATE)) { values[nb++] = comp->stringMap[i]; (*nbneg)++; } } } else { int transno; xmlRegTransPtr trans; xmlRegAtomPtr atom; xmlRegStatePtr state; if (terminal != NULL) { if (exec->state->type == XML_REGEXP_FINAL_STATE) *terminal = 1; else *terminal = 0; } if (err) { if (exec->errState == NULL) return(-1); state = exec->errState; } else { if (exec->state == NULL) return(-1); state = exec->state; } for (transno = 0; (transno < state->nbTrans) && (nb < maxval); transno++) { trans = &state->trans[transno]; if (trans->to < 0) continue; atom = trans->atom; if ((atom == NULL) || (atom->valuep == NULL)) continue; if (trans->count == REGEXP_ALL_LAX_COUNTER) { /* this should not be reached but ... */ TODO; } else if (trans->count == REGEXP_ALL_COUNTER) { /* this should not be reached but ... */ TODO; } else if (trans->counter >= 0) { xmlRegCounterPtr counter = NULL; int count; if (err) count = exec->errCounts[trans->counter]; else count = exec->counts[trans->counter]; if (exec->comp != NULL) counter = &exec->comp->counters[trans->counter]; if ((counter == NULL) || (count < counter->max)) { if (atom->neg) values[nb++] = (xmlChar *) atom->valuep2; else values[nb++] = (xmlChar *) atom->valuep; (*nbval)++; } } else { if ((exec->comp != NULL) && (exec->comp->states[trans->to] != NULL) && (exec->comp->states[trans->to]->type != XML_REGEXP_SINK_STATE)) { if (atom->neg) values[nb++] = (xmlChar *) atom->valuep2; else values[nb++] = (xmlChar *) atom->valuep; (*nbval)++; } } } for (transno = 0; (transno < state->nbTrans) && (nb < maxval); transno++) { trans = &state->trans[transno]; if (trans->to < 0) continue; atom = trans->atom; if ((atom == NULL) || (atom->valuep == NULL)) continue; if (trans->count == REGEXP_ALL_LAX_COUNTER) { continue; } else if (trans->count == REGEXP_ALL_COUNTER) { continue; } else if (trans->counter >= 0) { continue; } else { if ((exec->comp->states[trans->to] != NULL) && (exec->comp->states[trans->to]->type == XML_REGEXP_SINK_STATE)) { if (atom->neg) values[nb++] = (xmlChar *) atom->valuep2; else values[nb++] = (xmlChar *) atom->valuep; (*nbneg)++; } } } } return(0); } /** * xmlRegExecNextValues: * @exec: a regexp execution context * @nbval: pointer to the number of accepted values IN/OUT * @nbneg: return number of negative transitions * @values: pointer to the array of acceptable values * @terminal: return value if this was a terminal state * * Extract information from the regexp execution, * the parameter @values must point to an array of @nbval string pointers * on return nbval will contain the number of possible strings in that * state and the @values array will be updated with them. The string values * returned will be freed with the @exec context and don't need to be * deallocated. * * Returns: 0 in case of success or -1 in case of error. */ int xmlRegExecNextValues(xmlRegExecCtxtPtr exec, int *nbval, int *nbneg, xmlChar **values, int *terminal) { return(xmlRegExecGetValues(exec, 0, nbval, nbneg, values, terminal)); } /** * xmlRegExecErrInfo: * @exec: a regexp execution context generating an error * @string: return value for the error string * @nbval: pointer to the number of accepted values IN/OUT * @nbneg: return number of negative transitions * @values: pointer to the array of acceptable values * @terminal: return value if this was a terminal state * * Extract error information from the regexp execution, the parameter * @string will be updated with the value pushed and not accepted, * the parameter @values must point to an array of @nbval string pointers * on return nbval will contain the number of possible strings in that * state and the @values array will be updated with them. The string values * returned will be freed with the @exec context and don't need to be * deallocated. * * Returns: 0 in case of success or -1 in case of error. */ int xmlRegExecErrInfo(xmlRegExecCtxtPtr exec, const xmlChar **string, int *nbval, int *nbneg, xmlChar **values, int *terminal) { if (exec == NULL) return(-1); if (string != NULL) { if (exec->status != 0) *string = exec->errString; else *string = NULL; } return(xmlRegExecGetValues(exec, 1, nbval, nbneg, values, terminal)); } #if 0 static int xmlRegExecPushChar(xmlRegExecCtxtPtr exec, int UCS) { xmlRegTransPtr trans; xmlRegAtomPtr atom; int ret; int codepoint, len; if (exec == NULL) return(-1); if (exec->status != 0) return(exec->status); while ((exec->status == 0) && ((exec->inputString[exec->index] != 0) || (exec->state->type != XML_REGEXP_FINAL_STATE))) { /* * End of input on non-terminal state, rollback, however we may * still have epsilon like transition for counted transitions * on counters, in that case don't break too early. */ if ((exec->inputString[exec->index] == 0) && (exec->counts == NULL)) goto rollback; exec->transcount = 0; for (;exec->transno < exec->state->nbTrans;exec->transno++) { trans = &exec->state->trans[exec->transno]; if (trans->to < 0) continue; atom = trans->atom; ret = 0; if (trans->count >= 0) { int count; xmlRegCounterPtr counter; /* * A counted transition. */ count = exec->counts[trans->count]; counter = &exec->comp->counters[trans->count]; ret = ((count >= counter->min) && (count <= counter->max)); } else if (atom == NULL) { fprintf(stderr, "epsilon transition left at runtime\n"); exec->status = -2; break; } else if (exec->inputString[exec->index] != 0) { codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len); ret = xmlRegCheckCharacter(atom, codepoint); if ((ret == 1) && (atom->min > 0) && (atom->max > 0)) { xmlRegStatePtr to = exec->comp->states[trans->to]; /* * this is a multiple input sequence */ if (exec->state->nbTrans > exec->transno + 1) { xmlFARegExecSave(exec); } exec->transcount = 1; do { /* * Try to progress as much as possible on the input */ if (exec->transcount == atom->max) { break; } exec->index += len; /* * End of input: stop here */ if (exec->inputString[exec->index] == 0) { exec->index -= len; break; } if (exec->transcount >= atom->min) { int transno = exec->transno; xmlRegStatePtr state = exec->state; /* * The transition is acceptable save it */ exec->transno = -1; /* trick */ exec->state = to; xmlFARegExecSave(exec); exec->transno = transno; exec->state = state; } codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len); ret = xmlRegCheckCharacter(atom, codepoint); exec->transcount++; } while (ret == 1); if (exec->transcount < atom->min) ret = 0; /* * If the last check failed but one transition was found * possible, rollback */ if (ret < 0) ret = 0; if (ret == 0) { goto rollback; } } } if (ret == 1) { if (exec->state->nbTrans > exec->transno + 1) { xmlFARegExecSave(exec); } /* * restart count for expressions like this ((abc){2})* */ if (trans->count >= 0) { exec->counts[trans->count] = 0; } if (trans->counter >= 0) { exec->counts[trans->counter]++; } exec->state = exec->comp->states[trans->to]; exec->transno = 0; if (trans->atom != NULL) { exec->index += len; } goto progress; } else if (ret < 0) { exec->status = -4; break; } } if ((exec->transno != 0) || (exec->state->nbTrans == 0)) { rollback: /* * Failed to find a way out */ exec->determinist = 0; xmlFARegExecRollBack(exec); } progress: continue; } } #endif /************************************************************************ * * * Parser for the Schemas Datatype Regular Expressions * * http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/#regexs * * * ************************************************************************/ /** * xmlFAIsChar: * @ctxt: a regexp parser context * * [10] Char ::= [^.\?*+()|#x5B#x5D] */ static int xmlFAIsChar(xmlRegParserCtxtPtr ctxt) { int cur; int len; cur = CUR_SCHAR(ctxt->cur, len); if ((cur == '.') || (cur == '\\') || (cur == '?') || (cur == '*') || (cur == '+') || (cur == '(') || (cur == ')') || (cur == '|') || (cur == 0x5B) || (cur == 0x5D) || (cur == 0)) return(-1); return(cur); } /** * xmlFAParseCharProp: * @ctxt: a regexp parser context * * [27] charProp ::= IsCategory | IsBlock * [28] IsCategory ::= Letters | Marks | Numbers | Punctuation | * Separators | Symbols | Others * [29] Letters ::= 'L' [ultmo]? * [30] Marks ::= 'M' [nce]? * [31] Numbers ::= 'N' [dlo]? * [32] Punctuation ::= 'P' [cdseifo]? * [33] Separators ::= 'Z' [slp]? * [34] Symbols ::= 'S' [mcko]? * [35] Others ::= 'C' [cfon]? * [36] IsBlock ::= 'Is' [a-zA-Z0-9#x2D]+ */ static void xmlFAParseCharProp(xmlRegParserCtxtPtr ctxt) { int cur; xmlRegAtomType type = (xmlRegAtomType) 0; xmlChar *blockName = NULL; cur = CUR; if (cur == 'L') { NEXT; cur = CUR; if (cur == 'u') { NEXT; type = XML_REGEXP_LETTER_UPPERCASE; } else if (cur == 'l') { NEXT; type = XML_REGEXP_LETTER_LOWERCASE; } else if (cur == 't') { NEXT; type = XML_REGEXP_LETTER_TITLECASE; } else if (cur == 'm') { NEXT; type = XML_REGEXP_LETTER_MODIFIER; } else if (cur == 'o') { NEXT; type = XML_REGEXP_LETTER_OTHERS; } else { type = XML_REGEXP_LETTER; } } else if (cur == 'M') { NEXT; cur = CUR; if (cur == 'n') { NEXT; /* nonspacing */ type = XML_REGEXP_MARK_NONSPACING; } else if (cur == 'c') { NEXT; /* spacing combining */ type = XML_REGEXP_MARK_SPACECOMBINING; } else if (cur == 'e') { NEXT; /* enclosing */ type = XML_REGEXP_MARK_ENCLOSING; } else { /* all marks */ type = XML_REGEXP_MARK; } } else if (cur == 'N') { NEXT; cur = CUR; if (cur == 'd') { NEXT; /* digital */ type = XML_REGEXP_NUMBER_DECIMAL; } else if (cur == 'l') { NEXT; /* letter */ type = XML_REGEXP_NUMBER_LETTER; } else if (cur == 'o') { NEXT; /* other */ type = XML_REGEXP_NUMBER_OTHERS; } else { /* all numbers */ type = XML_REGEXP_NUMBER; } } else if (cur == 'P') { NEXT; cur = CUR; if (cur == 'c') { NEXT; /* connector */ type = XML_REGEXP_PUNCT_CONNECTOR; } else if (cur == 'd') { NEXT; /* dash */ type = XML_REGEXP_PUNCT_DASH; } else if (cur == 's') { NEXT; /* open */ type = XML_REGEXP_PUNCT_OPEN; } else if (cur == 'e') { NEXT; /* close */ type = XML_REGEXP_PUNCT_CLOSE; } else if (cur == 'i') { NEXT; /* initial quote */ type = XML_REGEXP_PUNCT_INITQUOTE; } else if (cur == 'f') { NEXT; /* final quote */ type = XML_REGEXP_PUNCT_FINQUOTE; } else if (cur == 'o') { NEXT; /* other */ type = XML_REGEXP_PUNCT_OTHERS; } else { /* all punctuation */ type = XML_REGEXP_PUNCT; } } else if (cur == 'Z') { NEXT; cur = CUR; if (cur == 's') { NEXT; /* space */ type = XML_REGEXP_SEPAR_SPACE; } else if (cur == 'l') { NEXT; /* line */ type = XML_REGEXP_SEPAR_LINE; } else if (cur == 'p') { NEXT; /* paragraph */ type = XML_REGEXP_SEPAR_PARA; } else { /* all separators */ type = XML_REGEXP_SEPAR; } } else if (cur == 'S') { NEXT; cur = CUR; if (cur == 'm') { NEXT; type = XML_REGEXP_SYMBOL_MATH; /* math */ } else if (cur == 'c') { NEXT; type = XML_REGEXP_SYMBOL_CURRENCY; /* currency */ } else if (cur == 'k') { NEXT; type = XML_REGEXP_SYMBOL_MODIFIER; /* modifiers */ } else if (cur == 'o') { NEXT; type = XML_REGEXP_SYMBOL_OTHERS; /* other */ } else { /* all symbols */ type = XML_REGEXP_SYMBOL; } } else if (cur == 'C') { NEXT; cur = CUR; if (cur == 'c') { NEXT; /* control */ type = XML_REGEXP_OTHER_CONTROL; } else if (cur == 'f') { NEXT; /* format */ type = XML_REGEXP_OTHER_FORMAT; } else if (cur == 'o') { NEXT; /* private use */ type = XML_REGEXP_OTHER_PRIVATE; } else if (cur == 'n') { NEXT; /* not assigned */ type = XML_REGEXP_OTHER_NA; } else { /* all others */ type = XML_REGEXP_OTHER; } } else if (cur == 'I') { const xmlChar *start; NEXT; cur = CUR; if (cur != 's') { ERROR("IsXXXX expected"); return; } NEXT; start = ctxt->cur; cur = CUR; if (((cur >= 'a') && (cur <= 'z')) || ((cur >= 'A') && (cur <= 'Z')) || ((cur >= '0') && (cur <= '9')) || (cur == 0x2D)) { NEXT; cur = CUR; while (((cur >= 'a') && (cur <= 'z')) || ((cur >= 'A') && (cur <= 'Z')) || ((cur >= '0') && (cur <= '9')) || (cur == 0x2D)) { NEXT; cur = CUR; } } type = XML_REGEXP_BLOCK_NAME; blockName = xmlStrndup(start, ctxt->cur - start); } else { ERROR("Unknown char property"); return; } if (ctxt->atom == NULL) { ctxt->atom = xmlRegNewAtom(ctxt, type); if (ctxt->atom == NULL) { xmlFree(blockName); return; } ctxt->atom->valuep = blockName; } else if (ctxt->atom->type == XML_REGEXP_RANGES) { if (xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg, type, 0, 0, blockName) == NULL) { xmlFree(blockName); } } } static int parse_escaped_codeunit(xmlRegParserCtxtPtr ctxt) { int val = 0, i, cur; for (i = 0; i < 4; i++) { NEXT; val *= 16; cur = CUR; if (cur >= '0' && cur <= '9') { val += cur - '0'; } else if (cur >= 'A' && cur <= 'F') { val += cur - 'A' + 10; } else if (cur >= 'a' && cur <= 'f') { val += cur - 'a' + 10; } else { ERROR("Expecting hex digit"); return -1; } } return val; } static int parse_escaped_codepoint(xmlRegParserCtxtPtr ctxt) { int val = parse_escaped_codeunit(ctxt); if (0xD800 <= val && val <= 0xDBFF) { NEXT; if (CUR == '\\') { NEXT; if (CUR == 'u') { int low = parse_escaped_codeunit(ctxt); if (0xDC00 <= low && low <= 0xDFFF) { return (val - 0xD800) * 0x400 + (low - 0xDC00) + 0x10000; } } } ERROR("Invalid low surrogate pair code unit"); val = -1; } return val; } /** * xmlFAParseCharClassEsc: * @ctxt: a regexp parser context * * [23] charClassEsc ::= ( SingleCharEsc | MultiCharEsc | catEsc | complEsc ) * [24] SingleCharEsc ::= '\' [nrt\|.?*+(){}#x2D#x5B#x5D#x5E] * [25] catEsc ::= '\p{' charProp '}' * [26] complEsc ::= '\P{' charProp '}' * [37] MultiCharEsc ::= '.' | ('\' [sSiIcCdDwW]) */ static void xmlFAParseCharClassEsc(xmlRegParserCtxtPtr ctxt) { int cur; if (CUR == '.') { if (ctxt->atom == NULL) { ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_ANYCHAR); } else if (ctxt->atom->type == XML_REGEXP_RANGES) { xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg, XML_REGEXP_ANYCHAR, 0, 0, NULL); } NEXT; return; } if (CUR != '\\') { ERROR("Escaped sequence: expecting \\"); return; } NEXT; cur = CUR; if (cur == 'p') { NEXT; if (CUR != '{') { ERROR("Expecting '{'"); return; } NEXT; xmlFAParseCharProp(ctxt); if (CUR != '}') { ERROR("Expecting '}'"); return; } NEXT; } else if (cur == 'P') { NEXT; if (CUR != '{') { ERROR("Expecting '{'"); return; } NEXT; xmlFAParseCharProp(ctxt); if (ctxt->atom != NULL) ctxt->atom->neg = 1; if (CUR != '}') { ERROR("Expecting '}'"); return; } NEXT; } else if ((cur == 'n') || (cur == 'r') || (cur == 't') || (cur == '\\') || (cur == '|') || (cur == '.') || (cur == '?') || (cur == '*') || (cur == '+') || (cur == '(') || (cur == ')') || (cur == '{') || (cur == '}') || (cur == 0x2D) || (cur == 0x5B) || (cur == 0x5D) || (cur == 0x5E) || /* Non-standard escape sequences: * Java 1.8|.NET Core 3.1|MSXML 6 */ (cur == '!') || /* + | + | + */ (cur == '"') || /* + | + | + */ (cur == '#') || /* + | + | + */ (cur == '$') || /* + | + | + */ (cur == '%') || /* + | + | + */ (cur == ',') || /* + | + | + */ (cur == '/') || /* + | + | + */ (cur == ':') || /* + | + | + */ (cur == ';') || /* + | + | + */ (cur == '=') || /* + | + | + */ (cur == '>') || /* | + | + */ (cur == '@') || /* + | + | + */ (cur == '`') || /* + | + | + */ (cur == '~') || /* + | + | + */ (cur == 'u')) { /* | + | + */ if (ctxt->atom == NULL) { ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_CHARVAL); if (ctxt->atom != NULL) { switch (cur) { case 'n': ctxt->atom->codepoint = '\n'; break; case 'r': ctxt->atom->codepoint = '\r'; break; case 't': ctxt->atom->codepoint = '\t'; break; case 'u': cur = parse_escaped_codepoint(ctxt); if (cur < 0) { return; } ctxt->atom->codepoint = cur; break; default: ctxt->atom->codepoint = cur; } } } else if (ctxt->atom->type == XML_REGEXP_RANGES) { switch (cur) { case 'n': cur = '\n'; break; case 'r': cur = '\r'; break; case 't': cur = '\t'; break; } xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg, XML_REGEXP_CHARVAL, cur, cur, NULL); } NEXT; } else if ((cur == 's') || (cur == 'S') || (cur == 'i') || (cur == 'I') || (cur == 'c') || (cur == 'C') || (cur == 'd') || (cur == 'D') || (cur == 'w') || (cur == 'W')) { xmlRegAtomType type = XML_REGEXP_ANYSPACE; switch (cur) { case 's': type = XML_REGEXP_ANYSPACE; break; case 'S': type = XML_REGEXP_NOTSPACE; break; case 'i': type = XML_REGEXP_INITNAME; break; case 'I': type = XML_REGEXP_NOTINITNAME; break; case 'c': type = XML_REGEXP_NAMECHAR; break; case 'C': type = XML_REGEXP_NOTNAMECHAR; break; case 'd': type = XML_REGEXP_DECIMAL; break; case 'D': type = XML_REGEXP_NOTDECIMAL; break; case 'w': type = XML_REGEXP_REALCHAR; break; case 'W': type = XML_REGEXP_NOTREALCHAR; break; } NEXT; if (ctxt->atom == NULL) { ctxt->atom = xmlRegNewAtom(ctxt, type); } else if (ctxt->atom->type == XML_REGEXP_RANGES) { xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg, type, 0, 0, NULL); } } else { ERROR("Wrong escape sequence, misuse of character '\\'"); } } /** * xmlFAParseCharRange: * @ctxt: a regexp parser context * * [17] charRange ::= seRange | XmlCharRef | XmlCharIncDash * [18] seRange ::= charOrEsc '-' charOrEsc * [20] charOrEsc ::= XmlChar | SingleCharEsc * [21] XmlChar ::= [^\#x2D#x5B#x5D] * [22] XmlCharIncDash ::= [^\#x5B#x5D] */ static void xmlFAParseCharRange(xmlRegParserCtxtPtr ctxt) { int cur, len; int start = -1; int end = -1; if (CUR == '\0') { ERROR("Expecting ']'"); return; } cur = CUR; if (cur == '\\') { NEXT; cur = CUR; switch (cur) { case 'n': start = 0xA; break; case 'r': start = 0xD; break; case 't': start = 0x9; break; case '\\': case '|': case '.': case '-': case '^': case '?': case '*': case '+': case '{': case '}': case '(': case ')': case '[': case ']': start = cur; break; default: ERROR("Invalid escape value"); return; } end = start; len = 1; } else if ((cur != 0x5B) && (cur != 0x5D)) { end = start = CUR_SCHAR(ctxt->cur, len); } else { ERROR("Expecting a char range"); return; } /* * Since we are "inside" a range, we can assume ctxt->cur is past * the start of ctxt->string, and PREV should be safe */ if ((start == '-') && (NXT(1) != ']') && (PREV != '[') && (PREV != '^')) { NEXTL(len); return; } NEXTL(len); cur = CUR; if ((cur != '-') || (NXT(1) == '[') || (NXT(1) == ']')) { xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg, XML_REGEXP_CHARVAL, start, end, NULL); return; } NEXT; cur = CUR; if (cur == '\\') { NEXT; cur = CUR; switch (cur) { case 'n': end = 0xA; break; case 'r': end = 0xD; break; case 't': end = 0x9; break; case '\\': case '|': case '.': case '-': case '^': case '?': case '*': case '+': case '{': case '}': case '(': case ')': case '[': case ']': end = cur; break; default: ERROR("Invalid escape value"); return; } len = 1; } else if ((cur != '\0') && (cur != 0x5B) && (cur != 0x5D)) { end = CUR_SCHAR(ctxt->cur, len); } else { ERROR("Expecting the end of a char range"); return; } /* TODO check that the values are acceptable character ranges for XML */ if (end < start) { ERROR("End of range is before start of range"); } else { NEXTL(len); xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg, XML_REGEXP_CHARVAL, start, end, NULL); } return; } /** * xmlFAParsePosCharGroup: * @ctxt: a regexp parser context * * [14] posCharGroup ::= ( charRange | charClassEsc )+ */ static void xmlFAParsePosCharGroup(xmlRegParserCtxtPtr ctxt) { do { if (CUR == '\\') { xmlFAParseCharClassEsc(ctxt); } else { xmlFAParseCharRange(ctxt); } } while ((CUR != ']') && (CUR != '-') && (CUR != 0) && (ctxt->error == 0)); } /** * xmlFAParseCharGroup: * @ctxt: a regexp parser context * * [13] charGroup ::= posCharGroup | negCharGroup | charClassSub * [15] negCharGroup ::= '^' posCharGroup * [16] charClassSub ::= ( posCharGroup | negCharGroup ) '-' charClassExpr * [12] charClassExpr ::= '[' charGroup ']' */ static void xmlFAParseCharGroup(xmlRegParserCtxtPtr ctxt) { int neg = ctxt->neg; if (CUR == '^') { NEXT; ctxt->neg = !ctxt->neg; xmlFAParsePosCharGroup(ctxt); ctxt->neg = neg; } while ((CUR != ']') && (ctxt->error == 0)) { if ((CUR == '-') && (NXT(1) == '[')) { NEXT; /* eat the '-' */ NEXT; /* eat the '[' */ ctxt->neg = 2; xmlFAParseCharGroup(ctxt); ctxt->neg = neg; if (CUR == ']') { NEXT; } else { ERROR("charClassExpr: ']' expected"); } break; } else { xmlFAParsePosCharGroup(ctxt); } } } /** * xmlFAParseCharClass: * @ctxt: a regexp parser context * * [11] charClass ::= charClassEsc | charClassExpr * [12] charClassExpr ::= '[' charGroup ']' */ static void xmlFAParseCharClass(xmlRegParserCtxtPtr ctxt) { if (CUR == '[') { NEXT; ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_RANGES); if (ctxt->atom == NULL) return; xmlFAParseCharGroup(ctxt); if (CUR == ']') { NEXT; } else { ERROR("xmlFAParseCharClass: ']' expected"); } } else { xmlFAParseCharClassEsc(ctxt); } } /** * xmlFAParseQuantExact: * @ctxt: a regexp parser context * * [8] QuantExact ::= [0-9]+ * * Returns 0 if success or -1 in case of error */ static int xmlFAParseQuantExact(xmlRegParserCtxtPtr ctxt) { int ret = 0; int ok = 0; int overflow = 0; while ((CUR >= '0') && (CUR <= '9')) { if (ret > INT_MAX / 10) { overflow = 1; } else { int digit = CUR - '0'; ret *= 10; if (ret > INT_MAX - digit) overflow = 1; else ret += digit; } ok = 1; NEXT; } if ((ok != 1) || (overflow == 1)) { return(-1); } return(ret); } /** * xmlFAParseQuantifier: * @ctxt: a regexp parser context * * [4] quantifier ::= [?*+] | ( '{' quantity '}' ) * [5] quantity ::= quantRange | quantMin | QuantExact * [6] quantRange ::= QuantExact ',' QuantExact * [7] quantMin ::= QuantExact ',' * [8] QuantExact ::= [0-9]+ */ static int xmlFAParseQuantifier(xmlRegParserCtxtPtr ctxt) { int cur; cur = CUR; if ((cur == '?') || (cur == '*') || (cur == '+')) { if (ctxt->atom != NULL) { if (cur == '?') ctxt->atom->quant = XML_REGEXP_QUANT_OPT; else if (cur == '*') ctxt->atom->quant = XML_REGEXP_QUANT_MULT; else if (cur == '+') ctxt->atom->quant = XML_REGEXP_QUANT_PLUS; } NEXT; return(1); } if (cur == '{') { int min = 0, max = 0; NEXT; cur = xmlFAParseQuantExact(ctxt); if (cur >= 0) min = cur; else { ERROR("Improper quantifier"); } if (CUR == ',') { NEXT; if (CUR == '}') max = INT_MAX; else { cur = xmlFAParseQuantExact(ctxt); if (cur >= 0) max = cur; else { ERROR("Improper quantifier"); } } } if (CUR == '}') { NEXT; } else { ERROR("Unterminated quantifier"); } if (max == 0) max = min; if (ctxt->atom != NULL) { ctxt->atom->quant = XML_REGEXP_QUANT_RANGE; ctxt->atom->min = min; ctxt->atom->max = max; } return(1); } return(0); } /** * xmlFAParseAtom: * @ctxt: a regexp parser context * * [9] atom ::= Char | charClass | ( '(' regExp ')' ) */ static int xmlFAParseAtom(xmlRegParserCtxtPtr ctxt) { int codepoint, len; codepoint = xmlFAIsChar(ctxt); if (codepoint > 0) { ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_CHARVAL); if (ctxt->atom == NULL) return(-1); codepoint = CUR_SCHAR(ctxt->cur, len); ctxt->atom->codepoint = codepoint; NEXTL(len); return(1); } else if (CUR == '|') { return(0); } else if (CUR == 0) { return(0); } else if (CUR == ')') { return(0); } else if (CUR == '(') { xmlRegStatePtr start, oldend, start0; NEXT; if (ctxt->depth >= 50) { ERROR("xmlFAParseAtom: maximum nesting depth exceeded"); return(-1); } /* * this extra Epsilon transition is needed if we count with 0 allowed * unfortunately this can't be known at that point */ xmlFAGenerateEpsilonTransition(ctxt, ctxt->state, NULL); start0 = ctxt->state; xmlFAGenerateEpsilonTransition(ctxt, ctxt->state, NULL); start = ctxt->state; oldend = ctxt->end; ctxt->end = NULL; ctxt->atom = NULL; ctxt->depth++; xmlFAParseRegExp(ctxt, 0); ctxt->depth--; if (CUR == ')') { NEXT; } else { ERROR("xmlFAParseAtom: expecting ')'"); } ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_SUBREG); if (ctxt->atom == NULL) return(-1); ctxt->atom->start = start; ctxt->atom->start0 = start0; ctxt->atom->stop = ctxt->state; ctxt->end = oldend; return(1); } else if ((CUR == '[') || (CUR == '\\') || (CUR == '.')) { xmlFAParseCharClass(ctxt); return(1); } return(0); } /** * xmlFAParsePiece: * @ctxt: a regexp parser context * * [3] piece ::= atom quantifier? */ static int xmlFAParsePiece(xmlRegParserCtxtPtr ctxt) { int ret; ctxt->atom = NULL; ret = xmlFAParseAtom(ctxt); if (ret == 0) return(0); if (ctxt->atom == NULL) { ERROR("internal: no atom generated"); } xmlFAParseQuantifier(ctxt); return(1); } /** * xmlFAParseBranch: * @ctxt: a regexp parser context * @to: optional target to the end of the branch * * @to is used to optimize by removing duplicate path in automata * in expressions like (a|b)(c|d) * * [2] branch ::= piece* */ static int xmlFAParseBranch(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr to) { xmlRegStatePtr previous; int ret; previous = ctxt->state; ret = xmlFAParsePiece(ctxt); if (ret == 0) { /* Empty branch */ xmlFAGenerateEpsilonTransition(ctxt, previous, to); } else { if (xmlFAGenerateTransitions(ctxt, previous, (CUR=='|' || CUR==')' || CUR==0) ? to : NULL, ctxt->atom) < 0) { xmlRegFreeAtom(ctxt->atom); ctxt->atom = NULL; return(-1); } previous = ctxt->state; ctxt->atom = NULL; } while ((ret != 0) && (ctxt->error == 0)) { ret = xmlFAParsePiece(ctxt); if (ret != 0) { if (xmlFAGenerateTransitions(ctxt, previous, (CUR=='|' || CUR==')' || CUR==0) ? to : NULL, ctxt->atom) < 0) { xmlRegFreeAtom(ctxt->atom); ctxt->atom = NULL; return(-1); } previous = ctxt->state; ctxt->atom = NULL; } } return(0); } /** * xmlFAParseRegExp: * @ctxt: a regexp parser context * @top: is this the top-level expression ? * * [1] regExp ::= branch ( '|' branch )* */ static void xmlFAParseRegExp(xmlRegParserCtxtPtr ctxt, int top) { xmlRegStatePtr start, end; /* if not top start should have been generated by an epsilon trans */ start = ctxt->state; ctxt->end = NULL; xmlFAParseBranch(ctxt, NULL); if (top) { ctxt->state->type = XML_REGEXP_FINAL_STATE; } if (CUR != '|') { ctxt->end = ctxt->state; return; } end = ctxt->state; while ((CUR == '|') && (ctxt->error == 0)) { NEXT; ctxt->state = start; ctxt->end = NULL; xmlFAParseBranch(ctxt, end); } if (!top) { ctxt->state = end; ctxt->end = end; } } /************************************************************************ * * * The basic API * * * ************************************************************************/ /** * xmlRegexpPrint: * @output: the file for the output debug * @regexp: the compiled regexp * * Print the content of the compiled regular expression */ void xmlRegexpPrint(FILE *output, xmlRegexpPtr regexp) { int i; if (output == NULL) return; fprintf(output, " regexp: "); if (regexp == NULL) { fprintf(output, "NULL\n"); return; } fprintf(output, "'%s' ", regexp->string); fprintf(output, "\n"); fprintf(output, "%d atoms:\n", regexp->nbAtoms); for (i = 0;i < regexp->nbAtoms; i++) { fprintf(output, " %02d ", i); xmlRegPrintAtom(output, regexp->atoms[i]); } fprintf(output, "%d states:", regexp->nbStates); fprintf(output, "\n"); for (i = 0;i < regexp->nbStates; i++) { xmlRegPrintState(output, regexp->states[i]); } fprintf(output, "%d counters:\n", regexp->nbCounters); for (i = 0;i < regexp->nbCounters; i++) { fprintf(output, " %d: min %d max %d\n", i, regexp->counters[i].min, regexp->counters[i].max); } } /** * xmlRegexpCompile: * @regexp: a regular expression string * * Parses a regular expression conforming to XML Schemas Part 2 Datatype * Appendix F and builds an automata suitable for testing strings against * that regular expression * * Returns the compiled expression or NULL in case of error */ xmlRegexpPtr xmlRegexpCompile(const xmlChar *regexp) { xmlRegexpPtr ret = NULL; xmlRegParserCtxtPtr ctxt; ctxt = xmlRegNewParserCtxt(regexp); if (ctxt == NULL) return(NULL); /* initialize the parser */ ctxt->state = xmlRegStatePush(ctxt); if (ctxt->state == NULL) goto error; ctxt->start = ctxt->state; ctxt->end = NULL; /* parse the expression building an automata */ xmlFAParseRegExp(ctxt, 1); if (CUR != 0) { ERROR("xmlFAParseRegExp: extra characters"); } if (ctxt->error != 0) goto error; ctxt->end = ctxt->state; ctxt->start->type = XML_REGEXP_START_STATE; ctxt->end->type = XML_REGEXP_FINAL_STATE; /* remove the Epsilon except for counted transitions */ xmlFAEliminateEpsilonTransitions(ctxt); if (ctxt->error != 0) goto error; ret = xmlRegEpxFromParse(ctxt); error: xmlRegFreeParserCtxt(ctxt); return(ret); } /** * xmlRegexpExec: * @comp: the compiled regular expression * @content: the value to check against the regular expression * * Check if the regular expression generates the value * * Returns 1 if it matches, 0 if not and a negative value in case of error */ int xmlRegexpExec(xmlRegexpPtr comp, const xmlChar *content) { if ((comp == NULL) || (content == NULL)) return(-1); return(xmlFARegExec(comp, content)); } /** * xmlRegexpIsDeterminist: * @comp: the compiled regular expression * * Check if the regular expression is determinist * * Returns 1 if it yes, 0 if not and a negative value in case of error */ int xmlRegexpIsDeterminist(xmlRegexpPtr comp) { xmlAutomataPtr am; int ret; if (comp == NULL) return(-1); if (comp->determinist != -1) return(comp->determinist); am = xmlNewAutomata(); if (am == NULL) return(-1); if (am->states != NULL) { int i; for (i = 0;i < am->nbStates;i++) xmlRegFreeState(am->states[i]); xmlFree(am->states); } am->nbAtoms = comp->nbAtoms; am->atoms = comp->atoms; am->nbStates = comp->nbStates; am->states = comp->states; am->determinist = -1; am->flags = comp->flags; ret = xmlFAComputesDeterminism(am); am->atoms = NULL; am->states = NULL; xmlFreeAutomata(am); comp->determinist = ret; return(ret); } /** * xmlRegFreeRegexp: * @regexp: the regexp * * Free a regexp */ void xmlRegFreeRegexp(xmlRegexpPtr regexp) { int i; if (regexp == NULL) return; if (regexp->string != NULL) xmlFree(regexp->string); if (regexp->states != NULL) { for (i = 0;i < regexp->nbStates;i++) xmlRegFreeState(regexp->states[i]); xmlFree(regexp->states); } if (regexp->atoms != NULL) { for (i = 0;i < regexp->nbAtoms;i++) xmlRegFreeAtom(regexp->atoms[i]); xmlFree(regexp->atoms); } if (regexp->counters != NULL) xmlFree(regexp->counters); if (regexp->compact != NULL) xmlFree(regexp->compact); if (regexp->transdata != NULL) xmlFree(regexp->transdata); if (regexp->stringMap != NULL) { for (i = 0; i < regexp->nbstrings;i++) xmlFree(regexp->stringMap[i]); xmlFree(regexp->stringMap); } xmlFree(regexp); } #ifdef LIBXML_AUTOMATA_ENABLED /************************************************************************ * * * The Automata interface * * * ************************************************************************/ /** * xmlNewAutomata: * * Create a new automata * * Returns the new object or NULL in case of failure */ xmlAutomataPtr xmlNewAutomata(void) { xmlAutomataPtr ctxt; ctxt = xmlRegNewParserCtxt(NULL); if (ctxt == NULL) return(NULL); /* initialize the parser */ ctxt->state = xmlRegStatePush(ctxt); if (ctxt->state == NULL) { xmlFreeAutomata(ctxt); return(NULL); } ctxt->start = ctxt->state; ctxt->end = NULL; ctxt->start->type = XML_REGEXP_START_STATE; ctxt->flags = 0; return(ctxt); } /** * xmlFreeAutomata: * @am: an automata * * Free an automata */ void xmlFreeAutomata(xmlAutomataPtr am) { if (am == NULL) return; xmlRegFreeParserCtxt(am); } /** * xmlAutomataSetFlags: * @am: an automata * @flags: a set of internal flags * * Set some flags on the automata */ void xmlAutomataSetFlags(xmlAutomataPtr am, int flags) { if (am == NULL) return; am->flags |= flags; } /** * xmlAutomataGetInitState: * @am: an automata * * Initial state lookup * * Returns the initial state of the automata */ xmlAutomataStatePtr xmlAutomataGetInitState(xmlAutomataPtr am) { if (am == NULL) return(NULL); return(am->start); } /** * xmlAutomataSetFinalState: * @am: an automata * @state: a state in this automata * * Makes that state a final state * * Returns 0 or -1 in case of error */ int xmlAutomataSetFinalState(xmlAutomataPtr am, xmlAutomataStatePtr state) { if ((am == NULL) || (state == NULL)) return(-1); state->type = XML_REGEXP_FINAL_STATE; return(0); } /** * xmlAutomataNewTransition: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @token: the input string associated to that transition * @data: data passed to the callback function if the transition is activated * * If @to is NULL, this creates first a new target state in the automata * and then adds a transition from the @from state to the target state * activated by the value of @token * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewTransition(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, const xmlChar *token, void *data) { xmlRegAtomPtr atom; if ((am == NULL) || (from == NULL) || (token == NULL)) return(NULL); atom = xmlRegNewAtom(am, XML_REGEXP_STRING); if (atom == NULL) return(NULL); atom->data = data; atom->valuep = xmlStrdup(token); if (xmlFAGenerateTransitions(am, from, to, atom) < 0) { xmlRegFreeAtom(atom); return(NULL); } if (to == NULL) return(am->state); return(to); } /** * xmlAutomataNewTransition2: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @token: the first input string associated to that transition * @token2: the second input string associated to that transition * @data: data passed to the callback function if the transition is activated * * If @to is NULL, this creates first a new target state in the automata * and then adds a transition from the @from state to the target state * activated by the value of @token * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewTransition2(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, const xmlChar *token, const xmlChar *token2, void *data) { xmlRegAtomPtr atom; if ((am == NULL) || (from == NULL) || (token == NULL)) return(NULL); atom = xmlRegNewAtom(am, XML_REGEXP_STRING); if (atom == NULL) return(NULL); atom->data = data; if ((token2 == NULL) || (*token2 == 0)) { atom->valuep = xmlStrdup(token); } else { int lenn, lenp; xmlChar *str; lenn = strlen((char *) token2); lenp = strlen((char *) token); str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2); if (str == NULL) { xmlRegFreeAtom(atom); return(NULL); } memcpy(&str[0], token, lenp); str[lenp] = '|'; memcpy(&str[lenp + 1], token2, lenn); str[lenn + lenp + 1] = 0; atom->valuep = str; } if (xmlFAGenerateTransitions(am, from, to, atom) < 0) { xmlRegFreeAtom(atom); return(NULL); } if (to == NULL) return(am->state); return(to); } /** * xmlAutomataNewNegTrans: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @token: the first input string associated to that transition * @token2: the second input string associated to that transition * @data: data passed to the callback function if the transition is activated * * If @to is NULL, this creates first a new target state in the automata * and then adds a transition from the @from state to the target state * activated by any value except (@token,@token2) * Note that if @token2 is not NULL, then (X, NULL) won't match to follow # the semantic of XSD ##other * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewNegTrans(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, const xmlChar *token, const xmlChar *token2, void *data) { xmlRegAtomPtr atom; xmlChar err_msg[200]; if ((am == NULL) || (from == NULL) || (token == NULL)) return(NULL); atom = xmlRegNewAtom(am, XML_REGEXP_STRING); if (atom == NULL) return(NULL); atom->data = data; atom->neg = 1; if ((token2 == NULL) || (*token2 == 0)) { atom->valuep = xmlStrdup(token); } else { int lenn, lenp; xmlChar *str; lenn = strlen((char *) token2); lenp = strlen((char *) token); str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2); if (str == NULL) { xmlRegFreeAtom(atom); return(NULL); } memcpy(&str[0], token, lenp); str[lenp] = '|'; memcpy(&str[lenp + 1], token2, lenn); str[lenn + lenp + 1] = 0; atom->valuep = str; } snprintf((char *) err_msg, 199, "not %s", (const char *) atom->valuep); err_msg[199] = 0; atom->valuep2 = xmlStrdup(err_msg); if (xmlFAGenerateTransitions(am, from, to, atom) < 0) { xmlRegFreeAtom(atom); return(NULL); } am->negs++; if (to == NULL) return(am->state); return(to); } /** * xmlAutomataNewCountTrans2: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @token: the input string associated to that transition * @token2: the second input string associated to that transition * @min: the minimum successive occurrences of token * @max: the maximum successive occurrences of token * @data: data associated to the transition * * If @to is NULL, this creates first a new target state in the automata * and then adds a transition from the @from state to the target state * activated by a succession of input of value @token and @token2 and * whose number is between @min and @max * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewCountTrans2(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, const xmlChar *token, const xmlChar *token2, int min, int max, void *data) { xmlRegAtomPtr atom; int counter; if ((am == NULL) || (from == NULL) || (token == NULL)) return(NULL); if (min < 0) return(NULL); if ((max < min) || (max < 1)) return(NULL); atom = xmlRegNewAtom(am, XML_REGEXP_STRING); if (atom == NULL) return(NULL); if ((token2 == NULL) || (*token2 == 0)) { atom->valuep = xmlStrdup(token); if (atom->valuep == NULL) goto error; } else { int lenn, lenp; xmlChar *str; lenn = strlen((char *) token2); lenp = strlen((char *) token); str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2); if (str == NULL) goto error; memcpy(&str[0], token, lenp); str[lenp] = '|'; memcpy(&str[lenp + 1], token2, lenn); str[lenn + lenp + 1] = 0; atom->valuep = str; } atom->data = data; if (min == 0) atom->min = 1; else atom->min = min; atom->max = max; /* * associate a counter to the transition. */ counter = xmlRegGetCounter(am); if (counter < 0) goto error; am->counters[counter].min = min; am->counters[counter].max = max; /* xmlFAGenerateTransitions(am, from, to, atom); */ if (to == NULL) { to = xmlRegStatePush(am); if (to == NULL) goto error; } xmlRegStateAddTrans(am, from, atom, to, counter, -1); if (xmlRegAtomPush(am, atom) < 0) goto error; am->state = to; if (to == NULL) to = am->state; if (to == NULL) return(NULL); if (min == 0) xmlFAGenerateEpsilonTransition(am, from, to); return(to); error: xmlRegFreeAtom(atom); return(NULL); } /** * xmlAutomataNewCountTrans: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @token: the input string associated to that transition * @min: the minimum successive occurrences of token * @max: the maximum successive occurrences of token * @data: data associated to the transition * * If @to is NULL, this creates first a new target state in the automata * and then adds a transition from the @from state to the target state * activated by a succession of input of value @token and whose number * is between @min and @max * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewCountTrans(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, const xmlChar *token, int min, int max, void *data) { xmlRegAtomPtr atom; int counter; if ((am == NULL) || (from == NULL) || (token == NULL)) return(NULL); if (min < 0) return(NULL); if ((max < min) || (max < 1)) return(NULL); atom = xmlRegNewAtom(am, XML_REGEXP_STRING); if (atom == NULL) return(NULL); atom->valuep = xmlStrdup(token); if (atom->valuep == NULL) goto error; atom->data = data; if (min == 0) atom->min = 1; else atom->min = min; atom->max = max; /* * associate a counter to the transition. */ counter = xmlRegGetCounter(am); if (counter < 0) goto error; am->counters[counter].min = min; am->counters[counter].max = max; /* xmlFAGenerateTransitions(am, from, to, atom); */ if (to == NULL) { to = xmlRegStatePush(am); if (to == NULL) goto error; } xmlRegStateAddTrans(am, from, atom, to, counter, -1); if (xmlRegAtomPush(am, atom) < 0) goto error; am->state = to; if (to == NULL) to = am->state; if (to == NULL) return(NULL); if (min == 0) xmlFAGenerateEpsilonTransition(am, from, to); return(to); error: xmlRegFreeAtom(atom); return(NULL); } /** * xmlAutomataNewOnceTrans2: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @token: the input string associated to that transition * @token2: the second input string associated to that transition * @min: the minimum successive occurrences of token * @max: the maximum successive occurrences of token * @data: data associated to the transition * * If @to is NULL, this creates first a new target state in the automata * and then adds a transition from the @from state to the target state * activated by a succession of input of value @token and @token2 and whose * number is between @min and @max, moreover that transition can only be * crossed once. * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewOnceTrans2(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, const xmlChar *token, const xmlChar *token2, int min, int max, void *data) { xmlRegAtomPtr atom; int counter; if ((am == NULL) || (from == NULL) || (token == NULL)) return(NULL); if (min < 1) return(NULL); if (max < min) return(NULL); atom = xmlRegNewAtom(am, XML_REGEXP_STRING); if (atom == NULL) return(NULL); if ((token2 == NULL) || (*token2 == 0)) { atom->valuep = xmlStrdup(token); if (atom->valuep == NULL) goto error; } else { int lenn, lenp; xmlChar *str; lenn = strlen((char *) token2); lenp = strlen((char *) token); str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2); if (str == NULL) goto error; memcpy(&str[0], token, lenp); str[lenp] = '|'; memcpy(&str[lenp + 1], token2, lenn); str[lenn + lenp + 1] = 0; atom->valuep = str; } atom->data = data; atom->quant = XML_REGEXP_QUANT_ONCEONLY; atom->min = min; atom->max = max; /* * associate a counter to the transition. */ counter = xmlRegGetCounter(am); if (counter < 0) goto error; am->counters[counter].min = 1; am->counters[counter].max = 1; /* xmlFAGenerateTransitions(am, from, to, atom); */ if (to == NULL) { to = xmlRegStatePush(am); if (to == NULL) goto error; } xmlRegStateAddTrans(am, from, atom, to, counter, -1); if (xmlRegAtomPush(am, atom) < 0) goto error; am->state = to; return(to); error: xmlRegFreeAtom(atom); return(NULL); } /** * xmlAutomataNewOnceTrans: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @token: the input string associated to that transition * @min: the minimum successive occurrences of token * @max: the maximum successive occurrences of token * @data: data associated to the transition * * If @to is NULL, this creates first a new target state in the automata * and then adds a transition from the @from state to the target state * activated by a succession of input of value @token and whose number * is between @min and @max, moreover that transition can only be crossed * once. * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewOnceTrans(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, const xmlChar *token, int min, int max, void *data) { xmlRegAtomPtr atom; int counter; if ((am == NULL) || (from == NULL) || (token == NULL)) return(NULL); if (min < 1) return(NULL); if (max < min) return(NULL); atom = xmlRegNewAtom(am, XML_REGEXP_STRING); if (atom == NULL) return(NULL); atom->valuep = xmlStrdup(token); atom->data = data; atom->quant = XML_REGEXP_QUANT_ONCEONLY; atom->min = min; atom->max = max; /* * associate a counter to the transition. */ counter = xmlRegGetCounter(am); if (counter < 0) goto error; am->counters[counter].min = 1; am->counters[counter].max = 1; /* xmlFAGenerateTransitions(am, from, to, atom); */ if (to == NULL) { to = xmlRegStatePush(am); if (to == NULL) goto error; } xmlRegStateAddTrans(am, from, atom, to, counter, -1); if (xmlRegAtomPush(am, atom) < 0) goto error; am->state = to; return(to); error: xmlRegFreeAtom(atom); return(NULL); } /** * xmlAutomataNewState: * @am: an automata * * Create a new disconnected state in the automata * * Returns the new state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewState(xmlAutomataPtr am) { if (am == NULL) return(NULL); return(xmlRegStatePush(am)); } /** * xmlAutomataNewEpsilon: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * * If @to is NULL, this creates first a new target state in the automata * and then adds an epsilon transition from the @from state to the * target state * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewEpsilon(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to) { if ((am == NULL) || (from == NULL)) return(NULL); xmlFAGenerateEpsilonTransition(am, from, to); if (to == NULL) return(am->state); return(to); } /** * xmlAutomataNewAllTrans: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @lax: allow to transition if not all all transitions have been activated * * If @to is NULL, this creates first a new target state in the automata * and then adds a an ALL transition from the @from state to the * target state. That transition is an epsilon transition allowed only when * all transitions from the @from node have been activated. * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewAllTrans(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, int lax) { if ((am == NULL) || (from == NULL)) return(NULL); xmlFAGenerateAllTransition(am, from, to, lax); if (to == NULL) return(am->state); return(to); } /** * xmlAutomataNewCounter: * @am: an automata * @min: the minimal value on the counter * @max: the maximal value on the counter * * Create a new counter * * Returns the counter number or -1 in case of error */ int xmlAutomataNewCounter(xmlAutomataPtr am, int min, int max) { int ret; if (am == NULL) return(-1); ret = xmlRegGetCounter(am); if (ret < 0) return(-1); am->counters[ret].min = min; am->counters[ret].max = max; return(ret); } /** * xmlAutomataNewCountedTrans: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @counter: the counter associated to that transition * * If @to is NULL, this creates first a new target state in the automata * and then adds an epsilon transition from the @from state to the target state * which will increment the counter provided * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewCountedTrans(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, int counter) { if ((am == NULL) || (from == NULL) || (counter < 0)) return(NULL); xmlFAGenerateCountedEpsilonTransition(am, from, to, counter); if (to == NULL) return(am->state); return(to); } /** * xmlAutomataNewCounterTrans: * @am: an automata * @from: the starting point of the transition * @to: the target point of the transition or NULL * @counter: the counter associated to that transition * * If @to is NULL, this creates first a new target state in the automata * and then adds an epsilon transition from the @from state to the target state * which will be allowed only if the counter is within the right range. * * Returns the target state or NULL in case of error */ xmlAutomataStatePtr xmlAutomataNewCounterTrans(xmlAutomataPtr am, xmlAutomataStatePtr from, xmlAutomataStatePtr to, int counter) { if ((am == NULL) || (from == NULL) || (counter < 0)) return(NULL); xmlFAGenerateCountedTransition(am, from, to, counter); if (to == NULL) return(am->state); return(to); } /** * xmlAutomataCompile: * @am: an automata * * Compile the automata into a Reg Exp ready for being executed. * The automata should be free after this point. * * Returns the compiled regexp or NULL in case of error */ xmlRegexpPtr xmlAutomataCompile(xmlAutomataPtr am) { xmlRegexpPtr ret; if ((am == NULL) || (am->error != 0)) return(NULL); xmlFAEliminateEpsilonTransitions(am); /* xmlFAComputesDeterminism(am); */ ret = xmlRegEpxFromParse(am); return(ret); } /** * xmlAutomataIsDeterminist: * @am: an automata * * Checks if an automata is determinist. * * Returns 1 if true, 0 if not, and -1 in case of error */ int xmlAutomataIsDeterminist(xmlAutomataPtr am) { int ret; if (am == NULL) return(-1); ret = xmlFAComputesDeterminism(am); return(ret); } #endif /* LIBXML_AUTOMATA_ENABLED */ #ifdef LIBXML_EXPR_ENABLED /************************************************************************ * * * Formal Expression handling code * * * ************************************************************************/ /************************************************************************ * * * Expression handling context * * * ************************************************************************/ struct _xmlExpCtxt { xmlDictPtr dict; xmlExpNodePtr *table; int size; int nbElems; int nb_nodes; int maxNodes; const char *expr; const char *cur; int nb_cons; int tabSize; }; /** * xmlExpNewCtxt: * @maxNodes: the maximum number of nodes * @dict: optional dictionary to use internally * * Creates a new context for manipulating expressions * * Returns the context or NULL in case of error */ xmlExpCtxtPtr xmlExpNewCtxt(int maxNodes, xmlDictPtr dict) { xmlExpCtxtPtr ret; int size = 256; if (maxNodes <= 4096) maxNodes = 4096; ret = (xmlExpCtxtPtr) xmlMalloc(sizeof(xmlExpCtxt)); if (ret == NULL) return(NULL); memset(ret, 0, sizeof(xmlExpCtxt)); ret->size = size; ret->nbElems = 0; ret->maxNodes = maxNodes; ret->table = xmlMalloc(size * sizeof(xmlExpNodePtr)); if (ret->table == NULL) { xmlFree(ret); return(NULL); } memset(ret->table, 0, size * sizeof(xmlExpNodePtr)); if (dict == NULL) { ret->dict = xmlDictCreate(); if (ret->dict == NULL) { xmlFree(ret->table); xmlFree(ret); return(NULL); } } else { ret->dict = dict; xmlDictReference(ret->dict); } return(ret); } /** * xmlExpFreeCtxt: * @ctxt: an expression context * * Free an expression context */ void xmlExpFreeCtxt(xmlExpCtxtPtr ctxt) { if (ctxt == NULL) return; xmlDictFree(ctxt->dict); if (ctxt->table != NULL) xmlFree(ctxt->table); xmlFree(ctxt); } /************************************************************************ * * * Structure associated to an expression node * * * ************************************************************************/ #define MAX_NODES 10000 /* * TODO: * - Wildcards * - public API for creation * * Started * - regression testing * * Done * - split into module and test tool * - memleaks */ typedef enum { XML_EXP_NILABLE = (1 << 0) } xmlExpNodeInfo; #define IS_NILLABLE(node) ((node)->info & XML_EXP_NILABLE) struct _xmlExpNode { unsigned char type;/* xmlExpNodeType */ unsigned char info;/* OR of xmlExpNodeInfo */ unsigned short key; /* the hash key */ unsigned int ref; /* The number of references */ int c_max; /* the maximum length it can consume */ xmlExpNodePtr exp_left; xmlExpNodePtr next;/* the next node in the hash table or free list */ union { struct { int f_min; int f_max; } count; struct { xmlExpNodePtr f_right; } children; const xmlChar *f_str; } field; }; #define exp_min field.count.f_min #define exp_max field.count.f_max /* #define exp_left field.children.f_left */ #define exp_right field.children.f_right #define exp_str field.f_str static xmlExpNodePtr xmlExpNewNode(xmlExpCtxtPtr ctxt, xmlExpNodeType type); static xmlExpNode forbiddenExpNode = { XML_EXP_FORBID, 0, 0, 0, 0, NULL, NULL, {{ 0, 0}} }; xmlExpNodePtr forbiddenExp = &forbiddenExpNode; static xmlExpNode emptyExpNode = { XML_EXP_EMPTY, 1, 0, 0, 0, NULL, NULL, {{ 0, 0}} }; xmlExpNodePtr emptyExp = &emptyExpNode; /************************************************************************ * * * The custom hash table for unicity and canonicalization * * of sub-expressions pointers * * * ************************************************************************/ /* * xmlExpHashNameComputeKey: * Calculate the hash key for a token */ static unsigned short xmlExpHashNameComputeKey(const xmlChar *name) { unsigned short value = 0L; char ch; if (name != NULL) { value += 30 * (*name); while ((ch = *name++) != 0) { value = value ^ ((value << 5) + (value >> 3) + (unsigned long)ch); } } return (value); } /* * xmlExpHashComputeKey: * Calculate the hash key for a compound expression */ static unsigned short xmlExpHashComputeKey(xmlExpNodeType type, xmlExpNodePtr left, xmlExpNodePtr right) { unsigned long value; unsigned short ret; switch (type) { case XML_EXP_SEQ: value = left->key; value += right->key; value *= 3; ret = (unsigned short) value; break; case XML_EXP_OR: value = left->key; value += right->key; value *= 7; ret = (unsigned short) value; break; case XML_EXP_COUNT: value = left->key; value += right->key; ret = (unsigned short) value; break; default: ret = 0; } return(ret); } static xmlExpNodePtr xmlExpNewNode(xmlExpCtxtPtr ctxt, xmlExpNodeType type) { xmlExpNodePtr ret; if (ctxt->nb_nodes >= MAX_NODES) return(NULL); ret = (xmlExpNodePtr) xmlMalloc(sizeof(xmlExpNode)); if (ret == NULL) return(NULL); memset(ret, 0, sizeof(xmlExpNode)); ret->type = type; ret->next = NULL; ctxt->nb_nodes++; ctxt->nb_cons++; return(ret); } /** * xmlExpHashGetEntry: * @table: the hash table * * Get the unique entry from the hash table. The entry is created if * needed. @left and @right are consumed, i.e. their ref count will * be decremented by the operation. * * Returns the pointer or NULL in case of error */ static xmlExpNodePtr xmlExpHashGetEntry(xmlExpCtxtPtr ctxt, xmlExpNodeType type, xmlExpNodePtr left, xmlExpNodePtr right, const xmlChar *name, int min, int max) { unsigned short kbase, key; xmlExpNodePtr entry; xmlExpNodePtr insert; if (ctxt == NULL) return(NULL); /* * Check for duplicate and insertion location. */ if (type == XML_EXP_ATOM) { kbase = xmlExpHashNameComputeKey(name); } else if (type == XML_EXP_COUNT) { /* COUNT reduction rule 1 */ /* a{1} -> a */ if (min == max) { if (min == 1) { return(left); } if (min == 0) { xmlExpFree(ctxt, left); return(emptyExp); } } if (min < 0) { xmlExpFree(ctxt, left); return(forbiddenExp); } if (max == -1) kbase = min + 79; else kbase = max - min; kbase += left->key; } else if (type == XML_EXP_OR) { /* Forbid reduction rules */ if (left->type == XML_EXP_FORBID) { xmlExpFree(ctxt, left); return(right); } if (right->type == XML_EXP_FORBID) { xmlExpFree(ctxt, right); return(left); } /* OR reduction rule 1 */ /* a | a reduced to a */ if (left == right) { xmlExpFree(ctxt, right); return(left); } /* OR canonicalization rule 1 */ /* linearize (a | b) | c into a | (b | c) */ if ((left->type == XML_EXP_OR) && (right->type != XML_EXP_OR)) { xmlExpNodePtr tmp = left; left = right; right = tmp; } /* OR reduction rule 2 */ /* a | (a | b) and b | (a | b) are reduced to a | b */ if (right->type == XML_EXP_OR) { if ((left == right->exp_left) || (left == right->exp_right)) { xmlExpFree(ctxt, left); return(right); } } /* OR canonicalization rule 2 */ /* linearize (a | b) | c into a | (b | c) */ if (left->type == XML_EXP_OR) { xmlExpNodePtr tmp; /* OR canonicalization rule 2 */ if ((left->exp_right->type != XML_EXP_OR) && (left->exp_right->key < left->exp_left->key)) { tmp = left->exp_right; left->exp_right = left->exp_left; left->exp_left = tmp; } left->exp_right->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left->exp_right, right, NULL, 0, 0); left->exp_left->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left->exp_left, tmp, NULL, 0, 0); xmlExpFree(ctxt, left); return(tmp); } if (right->type == XML_EXP_OR) { /* Ordering in the tree */ /* C | (A | B) -> A | (B | C) */ if (left->key > right->exp_right->key) { xmlExpNodePtr tmp; right->exp_right->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_right, left, NULL, 0, 0); right->exp_left->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_left, tmp, NULL, 0, 0); xmlExpFree(ctxt, right); return(tmp); } /* Ordering in the tree */ /* B | (A | C) -> A | (B | C) */ if (left->key > right->exp_left->key) { xmlExpNodePtr tmp; right->exp_right->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left, right->exp_right, NULL, 0, 0); right->exp_left->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_left, tmp, NULL, 0, 0); xmlExpFree(ctxt, right); return(tmp); } } /* we know both types are != XML_EXP_OR here */ else if (left->key > right->key) { xmlExpNodePtr tmp = left; left = right; right = tmp; } kbase = xmlExpHashComputeKey(type, left, right); } else if (type == XML_EXP_SEQ) { /* Forbid reduction rules */ if (left->type == XML_EXP_FORBID) { xmlExpFree(ctxt, right); return(left); } if (right->type == XML_EXP_FORBID) { xmlExpFree(ctxt, left); return(right); } /* Empty reduction rules */ if (right->type == XML_EXP_EMPTY) { return(left); } if (left->type == XML_EXP_EMPTY) { return(right); } kbase = xmlExpHashComputeKey(type, left, right); } else return(NULL); key = kbase % ctxt->size; if (ctxt->table[key] != NULL) { for (insert = ctxt->table[key]; insert != NULL; insert = insert->next) { if ((insert->key == kbase) && (insert->type == type)) { if (type == XML_EXP_ATOM) { if (name == insert->exp_str) { insert->ref++; return(insert); } } else if (type == XML_EXP_COUNT) { if ((insert->exp_min == min) && (insert->exp_max == max) && (insert->exp_left == left)) { insert->ref++; left->ref--; return(insert); } } else if ((insert->exp_left == left) && (insert->exp_right == right)) { insert->ref++; left->ref--; right->ref--; return(insert); } } } } entry = xmlExpNewNode(ctxt, type); if (entry == NULL) return(NULL); entry->key = kbase; if (type == XML_EXP_ATOM) { entry->exp_str = name; entry->c_max = 1; } else if (type == XML_EXP_COUNT) { entry->exp_min = min; entry->exp_max = max; entry->exp_left = left; if ((min == 0) || (IS_NILLABLE(left))) entry->info |= XML_EXP_NILABLE; if (max < 0) entry->c_max = -1; else entry->c_max = max * entry->exp_left->c_max; } else { entry->exp_left = left; entry->exp_right = right; if (type == XML_EXP_OR) { if ((IS_NILLABLE(left)) || (IS_NILLABLE(right))) entry->info |= XML_EXP_NILABLE; if ((entry->exp_left->c_max == -1) || (entry->exp_right->c_max == -1)) entry->c_max = -1; else if (entry->exp_left->c_max > entry->exp_right->c_max) entry->c_max = entry->exp_left->c_max; else entry->c_max = entry->exp_right->c_max; } else { if ((IS_NILLABLE(left)) && (IS_NILLABLE(right))) entry->info |= XML_EXP_NILABLE; if ((entry->exp_left->c_max == -1) || (entry->exp_right->c_max == -1)) entry->c_max = -1; else entry->c_max = entry->exp_left->c_max + entry->exp_right->c_max; } } entry->ref = 1; if (ctxt->table[key] != NULL) entry->next = ctxt->table[key]; ctxt->table[key] = entry; ctxt->nbElems++; return(entry); } /** * xmlExpFree: * @ctxt: the expression context * @exp: the expression * * Dereference the expression */ void xmlExpFree(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp) { if ((exp == NULL) || (exp == forbiddenExp) || (exp == emptyExp)) return; exp->ref--; if (exp->ref == 0) { unsigned short key; /* Unlink it first from the hash table */ key = exp->key % ctxt->size; if (ctxt->table[key] == exp) { ctxt->table[key] = exp->next; } else { xmlExpNodePtr tmp; tmp = ctxt->table[key]; while (tmp != NULL) { if (tmp->next == exp) { tmp->next = exp->next; break; } tmp = tmp->next; } } if ((exp->type == XML_EXP_SEQ) || (exp->type == XML_EXP_OR)) { xmlExpFree(ctxt, exp->exp_left); xmlExpFree(ctxt, exp->exp_right); } else if (exp->type == XML_EXP_COUNT) { xmlExpFree(ctxt, exp->exp_left); } xmlFree(exp); ctxt->nb_nodes--; } } /** * xmlExpRef: * @exp: the expression * * Increase the reference count of the expression */ void xmlExpRef(xmlExpNodePtr exp) { if (exp != NULL) exp->ref++; } /** * xmlExpNewAtom: * @ctxt: the expression context * @name: the atom name * @len: the atom name length in byte (or -1); * * Get the atom associated to this name from that context * * Returns the node or NULL in case of error */ xmlExpNodePtr xmlExpNewAtom(xmlExpCtxtPtr ctxt, const xmlChar *name, int len) { if ((ctxt == NULL) || (name == NULL)) return(NULL); name = xmlDictLookup(ctxt->dict, name, len); if (name == NULL) return(NULL); return(xmlExpHashGetEntry(ctxt, XML_EXP_ATOM, NULL, NULL, name, 0, 0)); } /** * xmlExpNewOr: * @ctxt: the expression context * @left: left expression * @right: right expression * * Get the atom associated to the choice @left | @right * Note that @left and @right are consumed in the operation, to keep * an handle on them use xmlExpRef() and use xmlExpFree() to release them, * this is true even in case of failure (unless ctxt == NULL). * * Returns the node or NULL in case of error */ xmlExpNodePtr xmlExpNewOr(xmlExpCtxtPtr ctxt, xmlExpNodePtr left, xmlExpNodePtr right) { if (ctxt == NULL) return(NULL); if ((left == NULL) || (right == NULL)) { xmlExpFree(ctxt, left); xmlExpFree(ctxt, right); return(NULL); } return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, left, right, NULL, 0, 0)); } /** * xmlExpNewSeq: * @ctxt: the expression context * @left: left expression * @right: right expression * * Get the atom associated to the sequence @left , @right * Note that @left and @right are consumed in the operation, to keep * an handle on them use xmlExpRef() and use xmlExpFree() to release them, * this is true even in case of failure (unless ctxt == NULL). * * Returns the node or NULL in case of error */ xmlExpNodePtr xmlExpNewSeq(xmlExpCtxtPtr ctxt, xmlExpNodePtr left, xmlExpNodePtr right) { if (ctxt == NULL) return(NULL); if ((left == NULL) || (right == NULL)) { xmlExpFree(ctxt, left); xmlExpFree(ctxt, right); return(NULL); } return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, left, right, NULL, 0, 0)); } /** * xmlExpNewRange: * @ctxt: the expression context * @subset: the expression to be repeated * @min: the lower bound for the repetition * @max: the upper bound for the repetition, -1 means infinite * * Get the atom associated to the range (@subset){@min, @max} * Note that @subset is consumed in the operation, to keep * an handle on it use xmlExpRef() and use xmlExpFree() to release it, * this is true even in case of failure (unless ctxt == NULL). * * Returns the node or NULL in case of error */ xmlExpNodePtr xmlExpNewRange(xmlExpCtxtPtr ctxt, xmlExpNodePtr subset, int min, int max) { if (ctxt == NULL) return(NULL); if ((subset == NULL) || (min < 0) || (max < -1) || ((max >= 0) && (min > max))) { xmlExpFree(ctxt, subset); return(NULL); } return(xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, subset, NULL, NULL, min, max)); } /************************************************************************ * * * Public API for operations on expressions * * * ************************************************************************/ static int xmlExpGetLanguageInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar**list, int len, int nb) { int tmp, tmp2; tail: switch (exp->type) { case XML_EXP_EMPTY: return(0); case XML_EXP_ATOM: for (tmp = 0;tmp < nb;tmp++) if (list[tmp] == exp->exp_str) return(0); if (nb >= len) return(-2); list[nb] = exp->exp_str; return(1); case XML_EXP_COUNT: exp = exp->exp_left; goto tail; case XML_EXP_SEQ: case XML_EXP_OR: tmp = xmlExpGetLanguageInt(ctxt, exp->exp_left, list, len, nb); if (tmp < 0) return(tmp); tmp2 = xmlExpGetLanguageInt(ctxt, exp->exp_right, list, len, nb + tmp); if (tmp2 < 0) return(tmp2); return(tmp + tmp2); } return(-1); } /** * xmlExpGetLanguage: * @ctxt: the expression context * @exp: the expression * @langList: where to store the tokens * @len: the allocated length of @list * * Find all the strings used in @exp and store them in @list * * Returns the number of unique strings found, -1 in case of errors and * -2 if there is more than @len strings */ int xmlExpGetLanguage(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar**langList, int len) { if ((ctxt == NULL) || (exp == NULL) || (langList == NULL) || (len <= 0)) return(-1); return(xmlExpGetLanguageInt(ctxt, exp, langList, len, 0)); } static int xmlExpGetStartInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar**list, int len, int nb) { int tmp, tmp2; tail: switch (exp->type) { case XML_EXP_FORBID: return(0); case XML_EXP_EMPTY: return(0); case XML_EXP_ATOM: for (tmp = 0;tmp < nb;tmp++) if (list[tmp] == exp->exp_str) return(0); if (nb >= len) return(-2); list[nb] = exp->exp_str; return(1); case XML_EXP_COUNT: exp = exp->exp_left; goto tail; case XML_EXP_SEQ: tmp = xmlExpGetStartInt(ctxt, exp->exp_left, list, len, nb); if (tmp < 0) return(tmp); if (IS_NILLABLE(exp->exp_left)) { tmp2 = xmlExpGetStartInt(ctxt, exp->exp_right, list, len, nb + tmp); if (tmp2 < 0) return(tmp2); tmp += tmp2; } return(tmp); case XML_EXP_OR: tmp = xmlExpGetStartInt(ctxt, exp->exp_left, list, len, nb); if (tmp < 0) return(tmp); tmp2 = xmlExpGetStartInt(ctxt, exp->exp_right, list, len, nb + tmp); if (tmp2 < 0) return(tmp2); return(tmp + tmp2); } return(-1); } /** * xmlExpGetStart: * @ctxt: the expression context * @exp: the expression * @tokList: where to store the tokens * @len: the allocated length of @list * * Find all the strings that appears at the start of the languages * accepted by @exp and store them in @list. E.g. for (a, b) | c * it will return the list [a, c] * * Returns the number of unique strings found, -1 in case of errors and * -2 if there is more than @len strings */ int xmlExpGetStart(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar**tokList, int len) { if ((ctxt == NULL) || (exp == NULL) || (tokList == NULL) || (len <= 0)) return(-1); return(xmlExpGetStartInt(ctxt, exp, tokList, len, 0)); } /** * xmlExpIsNillable: * @exp: the expression * * Finds if the expression is nillable, i.e. if it accepts the empty sequence * * Returns 1 if nillable, 0 if not and -1 in case of error */ int xmlExpIsNillable(xmlExpNodePtr exp) { if (exp == NULL) return(-1); return(IS_NILLABLE(exp) != 0); } static xmlExpNodePtr xmlExpStringDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar *str) { xmlExpNodePtr ret; switch (exp->type) { case XML_EXP_EMPTY: return(forbiddenExp); case XML_EXP_FORBID: return(forbiddenExp); case XML_EXP_ATOM: if (exp->exp_str == str) { ret = emptyExp; } else { /* TODO wildcards here */ ret = forbiddenExp; } return(ret); case XML_EXP_OR: { xmlExpNodePtr tmp; tmp = xmlExpStringDeriveInt(ctxt, exp->exp_left, str); if (tmp == NULL) { return(NULL); } ret = xmlExpStringDeriveInt(ctxt, exp->exp_right, str); if (ret == NULL) { xmlExpFree(ctxt, tmp); return(NULL); } ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, tmp, ret, NULL, 0, 0); return(ret); } case XML_EXP_SEQ: ret = xmlExpStringDeriveInt(ctxt, exp->exp_left, str); if (ret == NULL) { return(NULL); } else if (ret == forbiddenExp) { if (IS_NILLABLE(exp->exp_left)) { ret = xmlExpStringDeriveInt(ctxt, exp->exp_right, str); } } else { exp->exp_right->ref++; ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, exp->exp_right, NULL, 0, 0); } return(ret); case XML_EXP_COUNT: { int min, max; xmlExpNodePtr tmp; if (exp->exp_max == 0) return(forbiddenExp); ret = xmlExpStringDeriveInt(ctxt, exp->exp_left, str); if (ret == NULL) return(NULL); if (ret == forbiddenExp) { return(ret); } if (exp->exp_max == 1) return(ret); if (exp->exp_max < 0) /* unbounded */ max = -1; else max = exp->exp_max - 1; if (exp->exp_min > 0) min = exp->exp_min - 1; else min = 0; exp->exp_left->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left, NULL, NULL, min, max); if (ret == emptyExp) { return(tmp); } return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, tmp, NULL, 0, 0)); } } return(NULL); } /** * xmlExpStringDerive: * @ctxt: the expression context * @exp: the expression * @str: the string * @len: the string len in bytes if available * * Do one step of Brzozowski derivation of the expression @exp with * respect to the input string * * Returns the resulting expression or NULL in case of internal error */ xmlExpNodePtr xmlExpStringDerive(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar *str, int len) { const xmlChar *input; if ((exp == NULL) || (ctxt == NULL) || (str == NULL)) { return(NULL); } /* * check the string is in the dictionary, if yes use an interned * copy, otherwise we know it's not an acceptable input */ input = xmlDictExists(ctxt->dict, str, len); if (input == NULL) { return(forbiddenExp); } return(xmlExpStringDeriveInt(ctxt, exp, input)); } static int xmlExpCheckCard(xmlExpNodePtr exp, xmlExpNodePtr sub) { int ret = 1; if (sub->c_max == -1) { if (exp->c_max != -1) ret = 0; } else if ((exp->c_max >= 0) && (exp->c_max < sub->c_max)) { ret = 0; } #if 0 if ((IS_NILLABLE(sub)) && (!IS_NILLABLE(exp))) ret = 0; #endif return(ret); } static xmlExpNodePtr xmlExpExpDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub); /** * xmlExpDivide: * @ctxt: the expressions context * @exp: the englobing expression * @sub: the subexpression * @mult: the multiple expression * @remain: the remain from the derivation of the multiple * * Check if exp is a multiple of sub, i.e. if there is a finite number n * so that sub{n} subsume exp * * Returns the multiple value if successful, 0 if it is not a multiple * and -1 in case of internal error. */ static int xmlExpDivide(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub, xmlExpNodePtr *mult, xmlExpNodePtr *remain) { int i; xmlExpNodePtr tmp, tmp2; if (mult != NULL) *mult = NULL; if (remain != NULL) *remain = NULL; if (exp->c_max == -1) return(0); if (IS_NILLABLE(exp) && (!IS_NILLABLE(sub))) return(0); for (i = 1;i <= exp->c_max;i++) { sub->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, sub, NULL, NULL, i, i); if (tmp == NULL) { return(-1); } if (!xmlExpCheckCard(tmp, exp)) { xmlExpFree(ctxt, tmp); continue; } tmp2 = xmlExpExpDeriveInt(ctxt, tmp, exp); if (tmp2 == NULL) { xmlExpFree(ctxt, tmp); return(-1); } if ((tmp2 != forbiddenExp) && (IS_NILLABLE(tmp2))) { if (remain != NULL) *remain = tmp2; else xmlExpFree(ctxt, tmp2); if (mult != NULL) *mult = tmp; else xmlExpFree(ctxt, tmp); return(i); } xmlExpFree(ctxt, tmp); xmlExpFree(ctxt, tmp2); } return(0); } /** * xmlExpExpDeriveInt: * @ctxt: the expressions context * @exp: the englobing expression * @sub: the subexpression * * Try to do a step of Brzozowski derivation but at a higher level * the input being a subexpression. * * Returns the resulting expression or NULL in case of internal error */ static xmlExpNodePtr xmlExpExpDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) { xmlExpNodePtr ret, tmp, tmp2, tmp3; const xmlChar **tab; int len, i; /* * In case of equality and if the expression can only consume a finite * amount, then the derivation is empty */ if ((exp == sub) && (exp->c_max >= 0)) { return(emptyExp); } /* * decompose sub sequence first */ if (sub->type == XML_EXP_EMPTY) { exp->ref++; return(exp); } if (sub->type == XML_EXP_SEQ) { tmp = xmlExpExpDeriveInt(ctxt, exp, sub->exp_left); if (tmp == NULL) return(NULL); if (tmp == forbiddenExp) return(tmp); ret = xmlExpExpDeriveInt(ctxt, tmp, sub->exp_right); xmlExpFree(ctxt, tmp); return(ret); } if (sub->type == XML_EXP_OR) { tmp = xmlExpExpDeriveInt(ctxt, exp, sub->exp_left); if (tmp == forbiddenExp) return(tmp); if (tmp == NULL) return(NULL); ret = xmlExpExpDeriveInt(ctxt, exp, sub->exp_right); if ((ret == NULL) || (ret == forbiddenExp)) { xmlExpFree(ctxt, tmp); return(ret); } return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, tmp, ret, NULL, 0, 0)); } if (!xmlExpCheckCard(exp, sub)) { return(forbiddenExp); } switch (exp->type) { case XML_EXP_EMPTY: if (sub == emptyExp) return(emptyExp); return(forbiddenExp); case XML_EXP_FORBID: return(forbiddenExp); case XML_EXP_ATOM: if (sub->type == XML_EXP_ATOM) { /* TODO: handle wildcards */ if (exp->exp_str == sub->exp_str) { return(emptyExp); } return(forbiddenExp); } if ((sub->type == XML_EXP_COUNT) && (sub->exp_max == 1) && (sub->exp_left->type == XML_EXP_ATOM)) { /* TODO: handle wildcards */ if (exp->exp_str == sub->exp_left->exp_str) { return(emptyExp); } return(forbiddenExp); } return(forbiddenExp); case XML_EXP_SEQ: /* try to get the sequence consumed only if possible */ if (xmlExpCheckCard(exp->exp_left, sub)) { /* See if the sequence can be consumed directly */ ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub); if ((ret != forbiddenExp) && (ret != NULL)) { /* * TODO: assumption here that we are determinist * i.e. we won't get to a nillable exp left * subset which could be matched by the right * part too. * e.g.: (a | b)+,(a | c) and 'a+,a' */ exp->exp_right->ref++; return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, exp->exp_right, NULL, 0, 0)); } } /* Try instead to decompose */ if (sub->type == XML_EXP_COUNT) { int min, max; ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub->exp_left); if (ret == NULL) return(NULL); if (ret != forbiddenExp) { if (sub->exp_max < 0) max = -1; else max = sub->exp_max -1; if (sub->exp_min > 0) min = sub->exp_min -1; else min = 0; exp->exp_right->ref++; tmp = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, exp->exp_right, NULL, 0, 0); if (tmp == NULL) return(NULL); sub->exp_left->ref++; tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, sub->exp_left, NULL, NULL, min, max); if (tmp2 == NULL) { xmlExpFree(ctxt, tmp); return(NULL); } ret = xmlExpExpDeriveInt(ctxt, tmp, tmp2); xmlExpFree(ctxt, tmp); xmlExpFree(ctxt, tmp2); return(ret); } } /* we made no progress on structured operations */ break; case XML_EXP_OR: ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub); if (ret == NULL) return(NULL); tmp = xmlExpExpDeriveInt(ctxt, exp->exp_right, sub); if (tmp == NULL) { xmlExpFree(ctxt, ret); return(NULL); } return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, tmp, NULL, 0, 0)); case XML_EXP_COUNT: { int min, max; if (sub->type == XML_EXP_COUNT) { /* * Try to see if the loop is completely subsumed */ tmp = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub->exp_left); if (tmp == NULL) return(NULL); if (tmp == forbiddenExp) { int mult; mult = xmlExpDivide(ctxt, sub->exp_left, exp->exp_left, NULL, &tmp); if (mult <= 0) { return(forbiddenExp); } if (sub->exp_max == -1) { max = -1; if (exp->exp_max == -1) { if (exp->exp_min <= sub->exp_min * mult) min = 0; else min = exp->exp_min - sub->exp_min * mult; } else { xmlExpFree(ctxt, tmp); return(forbiddenExp); } } else { if (exp->exp_max == -1) { if (exp->exp_min > sub->exp_min * mult) { max = -1; min = exp->exp_min - sub->exp_min * mult; } else { max = -1; min = 0; } } else { if (exp->exp_max < sub->exp_max * mult) { xmlExpFree(ctxt, tmp); return(forbiddenExp); } if (sub->exp_max * mult > exp->exp_min) min = 0; else min = exp->exp_min - sub->exp_max * mult; max = exp->exp_max - sub->exp_max * mult; } } } else if (!IS_NILLABLE(tmp)) { /* * TODO: loop here to try to grow if working on finite * blocks. */ xmlExpFree(ctxt, tmp); return(forbiddenExp); } else if (sub->exp_max == -1) { if (exp->exp_max == -1) { if (exp->exp_min <= sub->exp_min) { max = -1; min = 0; } else { max = -1; min = exp->exp_min - sub->exp_min; } } else if (exp->exp_min > sub->exp_min) { xmlExpFree(ctxt, tmp); return(forbiddenExp); } else { max = -1; min = 0; } } else { if (exp->exp_max == -1) { if (exp->exp_min > sub->exp_min) { max = -1; min = exp->exp_min - sub->exp_min; } else { max = -1; min = 0; } } else { if (exp->exp_max < sub->exp_max) { xmlExpFree(ctxt, tmp); return(forbiddenExp); } if (sub->exp_max > exp->exp_min) min = 0; else min = exp->exp_min - sub->exp_max; max = exp->exp_max - sub->exp_max; } } exp->exp_left->ref++; tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left, NULL, NULL, min, max); if (tmp2 == NULL) { return(NULL); } ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, tmp, tmp2, NULL, 0, 0); return(ret); } tmp = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub); if (tmp == NULL) return(NULL); if (tmp == forbiddenExp) { return(forbiddenExp); } if (exp->exp_min > 0) min = exp->exp_min - 1; else min = 0; if (exp->exp_max < 0) max = -1; else max = exp->exp_max - 1; exp->exp_left->ref++; tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left, NULL, NULL, min, max); if (tmp2 == NULL) return(NULL); ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, tmp, tmp2, NULL, 0, 0); return(ret); } } if (IS_NILLABLE(sub)) { if (!(IS_NILLABLE(exp))) return(forbiddenExp); else ret = emptyExp; } else ret = NULL; /* * here the structured derivation made no progress so * we use the default token based derivation to force one more step */ if (ctxt->tabSize == 0) ctxt->tabSize = 40; tab = (const xmlChar **) xmlMalloc(ctxt->tabSize * sizeof(const xmlChar *)); if (tab == NULL) { return(NULL); } /* * collect all the strings accepted by the subexpression on input */ len = xmlExpGetStartInt(ctxt, sub, tab, ctxt->tabSize, 0); while (len < 0) { const xmlChar **temp; temp = (const xmlChar **) xmlRealloc((xmlChar **) tab, ctxt->tabSize * 2 * sizeof(const xmlChar *)); if (temp == NULL) { xmlFree((xmlChar **) tab); return(NULL); } tab = temp; ctxt->tabSize *= 2; len = xmlExpGetStartInt(ctxt, sub, tab, ctxt->tabSize, 0); } for (i = 0;i < len;i++) { tmp = xmlExpStringDeriveInt(ctxt, exp, tab[i]); if ((tmp == NULL) || (tmp == forbiddenExp)) { xmlExpFree(ctxt, ret); xmlFree((xmlChar **) tab); return(tmp); } tmp2 = xmlExpStringDeriveInt(ctxt, sub, tab[i]); if ((tmp2 == NULL) || (tmp2 == forbiddenExp)) { xmlExpFree(ctxt, tmp); xmlExpFree(ctxt, ret); xmlFree((xmlChar **) tab); return(tmp); } tmp3 = xmlExpExpDeriveInt(ctxt, tmp, tmp2); xmlExpFree(ctxt, tmp); xmlExpFree(ctxt, tmp2); if ((tmp3 == NULL) || (tmp3 == forbiddenExp)) { xmlExpFree(ctxt, ret); xmlFree((xmlChar **) tab); return(tmp3); } if (ret == NULL) ret = tmp3; else { ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, tmp3, NULL, 0, 0); if (ret == NULL) { xmlFree((xmlChar **) tab); return(NULL); } } } xmlFree((xmlChar **) tab); return(ret); } /** * xmlExpExpDerive: * @ctxt: the expressions context * @exp: the englobing expression * @sub: the subexpression * * Evaluates the expression resulting from @exp consuming a sub expression @sub * Based on algebraic derivation and sometimes direct Brzozowski derivation * it usually takes less than linear time and can handle expressions generating * infinite languages. * * Returns the resulting expression or NULL in case of internal error, the * result must be freed */ xmlExpNodePtr xmlExpExpDerive(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) { if ((exp == NULL) || (ctxt == NULL) || (sub == NULL)) return(NULL); /* * O(1) speedups */ if (IS_NILLABLE(sub) && (!IS_NILLABLE(exp))) { return(forbiddenExp); } if (xmlExpCheckCard(exp, sub) == 0) { return(forbiddenExp); } return(xmlExpExpDeriveInt(ctxt, exp, sub)); } /** * xmlExpSubsume: * @ctxt: the expressions context * @exp: the englobing expression * @sub: the subexpression * * Check whether @exp accepts all the languages accepted by @sub * the input being a subexpression. * * Returns 1 if true 0 if false and -1 in case of failure. */ int xmlExpSubsume(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) { xmlExpNodePtr tmp; if ((exp == NULL) || (ctxt == NULL) || (sub == NULL)) return(-1); /* * TODO: speedup by checking the language of sub is a subset of the * language of exp */ /* * O(1) speedups */ if (IS_NILLABLE(sub) && (!IS_NILLABLE(exp))) { return(0); } if (xmlExpCheckCard(exp, sub) == 0) { return(0); } tmp = xmlExpExpDeriveInt(ctxt, exp, sub); if (tmp == NULL) return(-1); if (tmp == forbiddenExp) return(0); if (tmp == emptyExp) return(1); if ((tmp != NULL) && (IS_NILLABLE(tmp))) { xmlExpFree(ctxt, tmp); return(1); } xmlExpFree(ctxt, tmp); return(0); } /************************************************************************ * * * Parsing expression * * * ************************************************************************/ static xmlExpNodePtr xmlExpParseExpr(xmlExpCtxtPtr ctxt); #undef CUR #define CUR (*ctxt->cur) #undef NEXT #define NEXT ctxt->cur++; #undef IS_BLANK #define IS_BLANK(c) ((c == ' ') || (c == '\n') || (c == '\r') || (c == '\t')) #define SKIP_BLANKS while (IS_BLANK(*ctxt->cur)) ctxt->cur++; static int xmlExpParseNumber(xmlExpCtxtPtr ctxt) { int ret = 0; SKIP_BLANKS if (CUR == '*') { NEXT return(-1); } if ((CUR < '0') || (CUR > '9')) return(-1); while ((CUR >= '0') && (CUR <= '9')) { ret = ret * 10 + (CUR - '0'); NEXT } return(ret); } static xmlExpNodePtr xmlExpParseOr(xmlExpCtxtPtr ctxt) { const char *base; xmlExpNodePtr ret; const xmlChar *val; SKIP_BLANKS base = ctxt->cur; if (*ctxt->cur == '(') { NEXT ret = xmlExpParseExpr(ctxt); SKIP_BLANKS if (*ctxt->cur != ')') { fprintf(stderr, "unbalanced '(' : %s\n", base); xmlExpFree(ctxt, ret); return(NULL); } NEXT; SKIP_BLANKS goto parse_quantifier; } while ((CUR != 0) && (!(IS_BLANK(CUR))) && (CUR != '(') && (CUR != ')') && (CUR != '|') && (CUR != ',') && (CUR != '{') && (CUR != '*') && (CUR != '+') && (CUR != '?') && (CUR != '}')) NEXT; val = xmlDictLookup(ctxt->dict, BAD_CAST base, ctxt->cur - base); if (val == NULL) return(NULL); ret = xmlExpHashGetEntry(ctxt, XML_EXP_ATOM, NULL, NULL, val, 0, 0); if (ret == NULL) return(NULL); SKIP_BLANKS parse_quantifier: if (CUR == '{') { int min, max; NEXT min = xmlExpParseNumber(ctxt); if (min < 0) { xmlExpFree(ctxt, ret); return(NULL); } SKIP_BLANKS if (CUR == ',') { NEXT max = xmlExpParseNumber(ctxt); SKIP_BLANKS } else max = min; if (CUR != '}') { xmlExpFree(ctxt, ret); return(NULL); } NEXT ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL, min, max); SKIP_BLANKS } else if (CUR == '?') { NEXT ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL, 0, 1); SKIP_BLANKS } else if (CUR == '+') { NEXT ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL, 1, -1); SKIP_BLANKS } else if (CUR == '*') { NEXT ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL, 0, -1); SKIP_BLANKS } return(ret); } static xmlExpNodePtr xmlExpParseSeq(xmlExpCtxtPtr ctxt) { xmlExpNodePtr ret, right; ret = xmlExpParseOr(ctxt); SKIP_BLANKS while (CUR == '|') { NEXT right = xmlExpParseOr(ctxt); if (right == NULL) { xmlExpFree(ctxt, ret); return(NULL); } ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, right, NULL, 0, 0); if (ret == NULL) return(NULL); } return(ret); } static xmlExpNodePtr xmlExpParseExpr(xmlExpCtxtPtr ctxt) { xmlExpNodePtr ret, right; ret = xmlExpParseSeq(ctxt); SKIP_BLANKS while (CUR == ',') { NEXT right = xmlExpParseSeq(ctxt); if (right == NULL) { xmlExpFree(ctxt, ret); return(NULL); } ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, right, NULL, 0, 0); if (ret == NULL) return(NULL); } return(ret); } /** * xmlExpParse: * @ctxt: the expressions context * @expr: the 0 terminated string * * Minimal parser for regexps, it understand the following constructs * - string terminals * - choice operator | * - sequence operator , * - subexpressions (...) * - usual cardinality operators + * and ? * - finite sequences { min, max } * - infinite sequences { min, * } * There is minimal checkings made especially no checking on strings values * * Returns a new expression or NULL in case of failure */ xmlExpNodePtr xmlExpParse(xmlExpCtxtPtr ctxt, const char *expr) { xmlExpNodePtr ret; ctxt->expr = expr; ctxt->cur = expr; ret = xmlExpParseExpr(ctxt); SKIP_BLANKS if (*ctxt->cur != 0) { xmlExpFree(ctxt, ret); return(NULL); } return(ret); } static void xmlExpDumpInt(xmlBufferPtr buf, xmlExpNodePtr expr, int glob) { xmlExpNodePtr c; if (expr == NULL) return; if (glob) xmlBufferWriteChar(buf, "("); switch (expr->type) { case XML_EXP_EMPTY: xmlBufferWriteChar(buf, "empty"); break; case XML_EXP_FORBID: xmlBufferWriteChar(buf, "forbidden"); break; case XML_EXP_ATOM: xmlBufferWriteCHAR(buf, expr->exp_str); break; case XML_EXP_SEQ: c = expr->exp_left; if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR)) xmlExpDumpInt(buf, c, 1); else xmlExpDumpInt(buf, c, 0); xmlBufferWriteChar(buf, " , "); c = expr->exp_right; if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR)) xmlExpDumpInt(buf, c, 1); else xmlExpDumpInt(buf, c, 0); break; case XML_EXP_OR: c = expr->exp_left; if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR)) xmlExpDumpInt(buf, c, 1); else xmlExpDumpInt(buf, c, 0); xmlBufferWriteChar(buf, " | "); c = expr->exp_right; if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR)) xmlExpDumpInt(buf, c, 1); else xmlExpDumpInt(buf, c, 0); break; case XML_EXP_COUNT: { char rep[40]; c = expr->exp_left; if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR)) xmlExpDumpInt(buf, c, 1); else xmlExpDumpInt(buf, c, 0); if ((expr->exp_min == 0) && (expr->exp_max == 1)) { rep[0] = '?'; rep[1] = 0; } else if ((expr->exp_min == 0) && (expr->exp_max == -1)) { rep[0] = '*'; rep[1] = 0; } else if ((expr->exp_min == 1) && (expr->exp_max == -1)) { rep[0] = '+'; rep[1] = 0; } else if (expr->exp_max == expr->exp_min) { snprintf(rep, 39, "{%d}", expr->exp_min); } else if (expr->exp_max < 0) { snprintf(rep, 39, "{%d,inf}", expr->exp_min); } else { snprintf(rep, 39, "{%d,%d}", expr->exp_min, expr->exp_max); } rep[39] = 0; xmlBufferWriteChar(buf, rep); break; } default: fprintf(stderr, "Error in tree\n"); } if (glob) xmlBufferWriteChar(buf, ")"); } /** * xmlExpDump: * @buf: a buffer to receive the output * @expr: the compiled expression * * Serialize the expression as compiled to the buffer */ void xmlExpDump(xmlBufferPtr buf, xmlExpNodePtr expr) { if ((buf == NULL) || (expr == NULL)) return; xmlExpDumpInt(buf, expr, 0); } /** * xmlExpMaxToken: * @expr: a compiled expression * * Indicate the maximum number of input a expression can accept * * Returns the maximum length or -1 in case of error */ int xmlExpMaxToken(xmlExpNodePtr expr) { if (expr == NULL) return(-1); return(expr->c_max); } /** * xmlExpCtxtNbNodes: * @ctxt: an expression context * * Debugging facility provides the number of allocated nodes at a that point * * Returns the number of nodes in use or -1 in case of error */ int xmlExpCtxtNbNodes(xmlExpCtxtPtr ctxt) { if (ctxt == NULL) return(-1); return(ctxt->nb_nodes); } /** * xmlExpCtxtNbCons: * @ctxt: an expression context * * Debugging facility provides the number of allocated nodes over lifetime * * Returns the number of nodes ever allocated or -1 in case of error */ int xmlExpCtxtNbCons(xmlExpCtxtPtr ctxt) { if (ctxt == NULL) return(-1); return(ctxt->nb_cons); } #endif /* LIBXML_EXPR_ENABLED */ #endif /* LIBXML_REGEXP_ENABLED */