Edit
IABSD.fr/src/usr.bin/sed/process.c
millert
- usr.bin/sed/process.c
-
/* $OpenBSD: process.c,v 1.38 2024/08/28 14:30:26 millert Exp $ */ /*- * Copyright (c) 1992 Diomidis Spinellis. * Copyright (c) 1992, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Diomidis Spinellis of Imperial College, University of London. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <sys/types.h> #include <sys/stat.h> #include <sys/uio.h> #include <ctype.h> #include <err.h> #include <fcntl.h> #include <limits.h> #include <regex.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include "defs.h" #include "extern.h" static SPACE HS, PS, SS; #define pd PS.deleted #define ps PS.space #define psl PS.len #define psanl PS.append_newline #define hs HS.space #define hsl HS.len static inline int applies(struct s_command *); static void flush_appends(void); static void lputs(char *, size_t); static inline int regexec_e(regex_t *, const char *, int, int, size_t, size_t); static void regsub(SPACE *, char *, char *); static int substitute(struct s_command *); struct s_appends *appends; /* Array of pointers to strings to append. */ static size_t appendx; /* Index into appends array. */ size_t appendnum; /* Size of appends array. */ static int lastaddr; /* Set by applies if last address of a range. */ static int sdone; /* If any substitutes since last line input. */ /* Iov structure for 'w' commands. */ static regex_t *defpreg; size_t maxnsub; regmatch_t *match; #define OUT() do {\ fwrite(ps, 1, psl, outfile);\ if (psanl) fputc('\n', outfile);\ } while (0) void process(void) { struct s_command *cp; SPACE tspace; size_t len, oldpsl; char *p; for (linenum = 0; mf_getline(&PS, REPLACE);) { pd = 0; top: cp = prog; redirect: while (cp != NULL) { if (!applies(cp)) { cp = cp->next; continue; } switch (cp->code) { case '{': cp = cp->u.c; goto redirect; case 'a': if (appendx >= appendnum) { appends = xreallocarray(appends, appendnum, 2 * sizeof(struct s_appends)); appendnum *= 2; } appends[appendx].type = AP_STRING; appends[appendx].s = cp->t; appends[appendx].len = strlen(cp->t); appendx++; break; case 'b': cp = cp->u.c; goto redirect; case 'c': pd = 1; psl = 0; if (cp->a2 == NULL || lastaddr || lastline()) (void)fprintf(outfile, "%s", cp->t); break; case 'd': pd = 1; goto new; case 'D': if (pd) goto new; if (psl == 0 || (p = memchr(ps, '\n', psl)) == NULL) { pd = 1; goto new; } else { psl -= (p + 1) - ps; memmove(ps, p + 1, psl); goto top; } case 'g': cspace(&PS, hs, hsl, REPLACE); break; case 'G': cspace(&PS, "\n", 1, 0); cspace(&PS, hs, hsl, 0); break; case 'h': cspace(&HS, ps, psl, REPLACE); break; case 'H': cspace(&HS, "\n", 1, 0); cspace(&HS, ps, psl, 0); break; case 'i': (void)fprintf(outfile, "%s", cp->t); break; case 'l': lputs(ps, psl); break; case 'n': if (!nflag && !pd) OUT(); flush_appends(); if (!mf_getline(&PS, REPLACE)) exit(0); pd = 0; break; case 'N': flush_appends(); cspace(&PS, "\n", 1, 0); if (!mf_getline(&PS, 0)) exit(0); break; case 'p': if (pd) break; OUT(); break; case 'P': if (pd) break; if ((p = memchr(ps, '\n', psl)) != NULL) { oldpsl = psl; psl = p - ps; psanl = 1; OUT(); psl = oldpsl; } else { OUT(); } break; case 'q': if (!nflag && !pd) OUT(); flush_appends(); finish_file(); exit(0); case 'r': if (appendx >= appendnum) { appends = xreallocarray(appends, appendnum, 2 * sizeof(struct s_appends)); appendnum *= 2; } appends[appendx].type = AP_FILE; appends[appendx].s = cp->t; appends[appendx].len = strlen(cp->t); appendx++; break; case 's': sdone |= substitute(cp); break; case 't': if (sdone) { sdone = 0; cp = cp->u.c; goto redirect; } break; case 'w': if (pd) break; if (cp->u.fd == -1 && (cp->u.fd = open(cp->t, O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1) err(1, "%s", cp->t); if ((size_t)write(cp->u.fd, ps, psl) != psl || write(cp->u.fd, "\n", 1) != 1) err(1, "%s", cp->t); break; case 'x': if (hs == NULL) cspace(&HS, "", 0, REPLACE); tspace = PS; PS = HS; psanl = tspace.append_newline; HS = tspace; break; case 'y': if (pd || psl == 0) break; for (p = ps, len = psl; len--; ++p) *p = cp->u.y[(unsigned char)*p]; break; case ':': case '}': break; case '=': (void)fprintf(outfile, "%lu\n", linenum); } cp = cp->next; } /* for all cp */ new: if (!nflag && !pd) OUT(); flush_appends(); } /* for all lines */ } /* * TRUE if the address passed matches the current program state * (lastline, linenumber, ps). */ #define MATCH(a) \ (a)->type == AT_RE ? regexec_e((a)->u.r, ps, 0, 1, 0, psl) : \ (a)->type == AT_LINE ? linenum == (a)->u.l : lastline() /* * Return TRUE if the command applies to the current line. Sets the inrange * flag to process ranges. Interprets the non-select (``!'') flag. */ static inline int applies(struct s_command *cp) { int r; lastaddr = 0; if (cp->a1 == NULL && cp->a2 == NULL) r = 1; else if (cp->a2) if (cp->inrange) { if (MATCH(cp->a2)) { cp->inrange = 0; lastaddr = 1; } r = 1; } else if (MATCH(cp->a1)) { /* * If the second address is a number less than or * equal to the line number first selected, only * one line shall be selected. * -- POSIX 1003.2 */ if (cp->a2->type == AT_LINE && linenum >= cp->a2->u.l) lastaddr = 1; else cp->inrange = 1; r = 1; } else r = 0; else r = MATCH(cp->a1); return (cp->nonsel ? !r : r); } /* * Reset all inrange markers. */ void resetstate(void) { struct s_command *cp; free(HS.back); memset(&HS, 0, sizeof(HS)); for (cp = prog; cp; cp = cp->code == '{' ? cp->u.c : cp->next) if (cp->a2) cp->inrange = 0; } /* * substitute -- * Do substitutions in the pattern space. Currently, we build a * copy of the new pattern space in the substitute space structure * and then swap them. */ static int substitute(struct s_command *cp) { SPACE tspace; regex_t *re; regoff_t slen; int n, lastempty; regoff_t le = 0; char *s; s = ps; re = cp->u.s->re; if (re == NULL) { if (defpreg != NULL && cp->u.s->maxbref > defpreg->re_nsub) { linenum = cp->u.s->linenum; error("\\%d not defined in the RE", cp->u.s->maxbref); } } if (!regexec_e(re, ps, 0, 0, 0, psl)) return (0); SS.len = 0; /* Clean substitute space. */ slen = psl; n = cp->u.s->n; lastempty = 1; do { /* Copy the leading retained string. */ if (n <= 1 && (match[0].rm_so > le)) cspace(&SS, s, match[0].rm_so - le, APPEND); /* Skip zero-length matches right after other matches. */ if (lastempty || (match[0].rm_so - le) || match[0].rm_so != match[0].rm_eo) { if (n <= 1) { /* Want this match: append replacement. */ regsub(&SS, ps, cp->u.s->new); if (n == 1) n = -1; } else { /* Want a later match: append original. */ if (match[0].rm_eo - le) cspace(&SS, s, match[0].rm_eo - le, APPEND); n--; } } /* Move past this match. */ s = ps + match[0].rm_eo; slen = psl - match[0].rm_eo; le = match[0].rm_eo; /* * After a zero-length match, advance one byte, * and at the end of the line, terminate. */ if (match[0].rm_so == match[0].rm_eo) { if (slen > 0) { cspace(&SS, s++, 1, APPEND); slen--; le++; } else slen = -1; lastempty = 1; } else lastempty = 0; } while (n >= 0 && slen >= 0 && regexec_e(re, ps, REG_NOTBOL, 0, le, psl)); /* Did not find the requested number of matches. */ if (n > 0) return (0); /* Copy the trailing retained string. */ if (slen > 0) cspace(&SS, s, slen, APPEND); /* * Swap the substitute space and the pattern space, and make sure * that any leftover pointers into stdio memory get lost. */ tspace = PS; PS = SS; psanl = tspace.append_newline; SS = tspace; SS.space = SS.back; /* Handle the 'p' flag. */ if (cp->u.s->p) OUT(); /* Handle the 'w' flag. */ if (cp->u.s->wfile && !pd) { if (cp->u.s->wfd == -1 && (cp->u.s->wfd = open(cp->u.s->wfile, O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, DEFFILEMODE)) == -1) err(1, "%s", cp->u.s->wfile); if ((size_t)write(cp->u.s->wfd, ps, psl) != psl || write(cp->u.s->wfd, "\n", 1) != 1) err(1, "%s", cp->u.s->wfile); } return (1); } /* * Flush append requests. Always called before reading a line, * therefore it also resets the substitution done (sdone) flag. */ static void flush_appends(void) { FILE *f; size_t count, idx; char buf[8 * 1024]; for (idx = 0; idx < appendx; idx++) switch (appends[idx].type) { case AP_STRING: fwrite(appends[idx].s, sizeof(char), appends[idx].len, outfile); break; case AP_FILE: /* * Read files probably shouldn't be cached. Since * it's not an error to read a non-existent file, * it's possible that another program is interacting * with the sed script through the file system. It * would be truly bizarre, but possible. It's probably * not that big a performance win, anyhow. */ if ((f = fopen(appends[idx].s, "r")) == NULL) break; while ((count = fread(buf, sizeof(char), sizeof(buf), f))) (void)fwrite(buf, sizeof(char), count, outfile); (void)fclose(f); break; } if (ferror(outfile)) err(1, "%s", outfname); appendx = sdone = 0; } static void lputs(char *s, size_t len) { int count; extern int termwidth; const char *escapes; char *p; for (count = 0; len > 0; len--, s++) { if (count >= termwidth) { (void)fprintf(outfile, "\\\n"); count = 0; } if (isascii((unsigned char)*s) && isprint((unsigned char)*s) && *s != '\\') { (void)fputc(*s, outfile); count++; } else if (*s == '\n') { (void)fputc('$', outfile); (void)fputc('\n', outfile); count = 0; } else { escapes = "\\\a\b\f\r\t\v"; (void)fputc('\\', outfile); if ((p = strchr(escapes, *s)) && *s != '\0') { (void)fputc("\\abfrtv"[p - escapes], outfile); count += 2; } else { (void)fprintf(outfile, "%03o", *(u_char *)s); count += 4; } } } (void)fputc('$', outfile); (void)fputc('\n', outfile); if (ferror(outfile)) err(1, "%s", outfname); } static inline int regexec_e(regex_t *preg, const char *string, int eflags, int nomatch, size_t start, size_t stop) { int eval; if (preg == NULL) { if (defpreg == NULL) errx(1, "first RE may not be empty"); } else defpreg = preg; /* Set anchors */ match[0].rm_so = start; match[0].rm_eo = stop; eval = regexec(defpreg, string, nomatch ? 0 : maxnsub + 1, match, eflags | REG_STARTEND); switch (eval) { case 0: return (1); case REG_NOMATCH: return (0); } errx(1, "RE error: %s", strregerror(eval, defpreg)); } /* * regsub - perform substitutions after a regexp match * Based on a routine by Henry Spencer */ static void regsub(SPACE *sp, char *string, char *src) { int len, no; char c, *dst; #define NEEDSP(reqlen) \ if (sp->len + (reqlen) + 1 >= sp->blen) { \ size_t newlen = sp->blen + (reqlen) + 1024; \ sp->space = sp->back = xrealloc(sp->back, newlen); \ sp->blen = newlen; \ dst = sp->space + sp->len; \ } dst = sp->space + sp->len; while ((c = *src++) != '\0') { if (c == '&') no = 0; else if (c == '\\' && isdigit((unsigned char)*src)) no = *src++ - '0'; else no = -1; if (no < 0) { /* Ordinary character. */ if (c == '\\' && (*src == '\\' || *src == '&')) c = *src++; NEEDSP(1); *dst++ = c; ++sp->len; } else if (match[no].rm_so != -1 && match[no].rm_eo != -1) { len = match[no].rm_eo - match[no].rm_so; NEEDSP(len); memmove(dst, string + match[no].rm_so, len); dst += len; sp->len += len; } } NEEDSP(1); *dst = '\0'; } /* * aspace -- * Append the source space to the destination space, allocating new * space as necessary. */ void cspace(SPACE *sp, const char *p, size_t len, enum e_spflag spflag) { size_t tlen; /* Make sure SPACE has enough memory and ramp up quickly. */ tlen = sp->len + len + 1; if (tlen > sp->blen) { size_t newlen = tlen + 1024; sp->space = sp->back = xrealloc(sp->back, newlen); sp->blen = newlen; } if (spflag == REPLACE) sp->len = 0; memmove(sp->space + sp->len, p, len); sp->space[sp->len += len] = '\0'; } /* * Close all cached opened files and report any errors */ void cfclose(struct s_command *cp, struct s_command *end) { for (; cp != end; cp = cp->next) switch (cp->code) { case 's': if (cp->u.s->wfd != -1 && close(cp->u.s->wfd)) err(1, "%s", cp->u.s->wfile); cp->u.s->wfd = -1; break; case 'w': if (cp->u.fd != -1 && close(cp->u.fd)) err(1, "%s", cp->t); cp->u.fd = -1; break; case '{': cfclose(cp->u.c, cp->next); break; } }