Edit
kc3-lang/freetype/src/type1z/t1parse.c
David Turner
- src/type1z/t1parse.c
-
/******************************************************************* * * t1parse.c 2.0 * * Type1 parser. * * Copyright 1996-1998 by * David Turner, Robert Wilhelm, and Werner Lemberg. * * This file is part of the FreeType project, and may only be used * modified and distributed under the terms of the FreeType project * license, LICENSE.TXT. By continuing to use, modify, or distribute * this file you indicate that you have read the license and * understand and accept it fully. * * The Type 1 parser is in charge of the following: * * - provide an implementation of a growing sequence of * objects called a T1_Table (used to build various tables * needed by the loader). * * - opening .pfb and .pfa files to extract their top-level * and private dictionaries * * - read numbers, arrays & strings from any dictionary * * See "t1load.c" to see how data is loaded from the font file * ******************************************************************/ #include <freetype/internal/ftdebug.h> #include <freetype/internal/ftcalc.h> #include <freetype/internal/ftobjs.h> #include <freetype/internal/ftstream.h> #include <t1errors.h> #include <t1parse.h> #undef FT_COMPONENT #define FT_COMPONENT trace_t1load /*************************************************************************/ /* */ /* <Function> T1_New_Table */ /* */ /* <Description> */ /* Initialise a T1_Table. */ /* */ /* <Input> */ /* table :: address of target table */ /* count :: table size = maximum number of elements */ /* memory :: memory object to use for all subsequent reallocations */ /* */ /* <Return> */ /* Error code. 0 means success */ /* */ LOCAL_FUNC T1_Error T1_New_Table( T1_Table* table, T1_Int count, FT_Memory memory ) { T1_Error error; table->memory = memory; if ( ALLOC_ARRAY( table->elements, count, T1_Byte* ) || ALLOC_ARRAY( table->lengths, count, T1_Byte* ) ) goto Exit; table->max_elems = count; table->init = 0xdeadbeef; table->num_elems = 0; table->block = 0; table->capacity = 0; table->cursor = 0; Exit: if (error) FREE(table->elements); return error; } /*************************************************************************/ /* */ /* <Function> T1_Add_Table */ /* */ /* <Description> */ /* Adds an object to a T1_Table, possibly growing its memory block */ /* */ /* <Input> */ /* table :: target table */ /* index :: index of object in table */ /* object :: address of object to copy in memory */ /* length :: length in bytes of source object */ /* */ /* <Return> */ /* Error code. 0 means success. An error is returned when a */ /* realloc failed.. */ /* */ static void shift_elements( T1_Table* table, T1_Byte* old_base ) { T1_Long delta = table->block - old_base; T1_Byte** offset = table->elements; T1_Byte** limit = offset + table->max_elems; if (delta) for ( ; offset < limit; offset++ ) { if (offset[0]) offset[0] += delta; } } static T1_Error reallocate_t1_table( T1_Table* table, T1_Int new_size ) { FT_Memory memory = table->memory; T1_Byte* old_base = table->block; T1_Error error; /* realloc the base block */ if ( REALLOC( table->block, table->capacity, new_size ) ) return error; table->capacity = new_size; /* shift all offsets when needed */ if (old_base) shift_elements( table, old_base ); return T1_Err_Ok; } LOCAL_FUNC T1_Error T1_Add_Table( T1_Table* table, T1_Int index, void* object, T1_Int length ) { if (index < 0 || index > table->max_elems) { FT_ERROR(( "T1.Add_Table: invalid index\n" )); return T1_Err_Syntax_Error; } /* grow the base block if needed */ if ( table->cursor + length > table->capacity ) { T1_Error error; T1_Int new_size = table->capacity; while ( new_size < table->cursor+length ) new_size += 1024; error = reallocate_t1_table( table, new_size ); if (error) return error; } /* add the object to the base block and adjust offset */ table->elements[ index ] = table->block + table->cursor; table->lengths [ index ] = length; MEM_Copy( table->block + table->cursor, object, length ); table->cursor += length; return T1_Err_Ok; } /*************************************************************************/ /* */ /* <Function> T1_Done_Table */ /* */ /* <Description> */ /* Finalise a T1_Table. (realloc it to its current cursor). */ /* */ /* <Input> */ /* table :: target table */ /* */ /* <Note> */ /* This function does NOT release the heap's memory block. It is up */ /* to the caller to clean it, or reference it in its own structures. */ /* */ #if 0 LOCAL_FUNC void T1_Done_Table( T1_Table* table ) { FT_Memory memory = table->memory; T1_Error error; T1_Byte* old_base; /* should never fail, as rec.cursor <= rec.size */ old_base = table->block; if (!old_base) return; (void)REALLOC( table->block, table->capacity, table->cursor ); table->capacity = table->cursor; if (old_base != table->block) shift_elements( table, old_base ); } #endif LOCAL_FUNC void T1_Release_Table( T1_Table* table ) { FT_Memory memory = table->memory; if (table->init == (FT_Long)0xdeadbeef) { FREE( table->block ); FREE( table->elements ); FREE( table->lengths ); table->init = 0; } } static T1_Long t1_toint( T1_Byte* *cursor, T1_Byte* limit ) { T1_Long result = 0; T1_Byte* cur = *cursor; T1_Byte c, d; for (; cur < limit; cur++) { c = *cur; d = (T1_Byte)(c - '0'); if (d < 10) break; if ( c=='-' ) { cur++; break; } } if (cur < limit) { do { d = (T1_Byte)(cur[0] - '0'); if (d >= 10) break; result = result*10 + d; cur++; } while (cur < limit); if (c == '-') result = -result; } *cursor = cur; return result; } static T1_Long t1_tofixed( T1_Byte* *cursor, T1_Byte* limit, T1_Long power_ten ) { T1_Byte* cur = *cursor; T1_Long num, divider, result; T1_Int sign = 0; T1_Byte d; if (cur >= limit) return 0; /* first of all, read the integer part */ result = t1_toint( &cur, limit ) << 16; num = 0; divider = 1; if (result < 0) { sign = 1; result = -result; } if (cur >= limit) goto Exit; /* read decimal part, if any */ if (*cur == '.' && cur+1 < limit) { cur++; for (;;) { d = (T1_Byte)(*cur - '0'); if (d >= 10) break; if (divider < 10000000L) { num = num*10 + d; divider *= 10; } cur++; if (cur >= limit) break; } } /* read exponent, if any */ if ( cur+1 < limit && (*cur == 'e' || *cur == 'E')) { cur++; power_ten += t1_toint( &cur, limit ); } Exit: /* raise to power of ten if needed */ while (power_ten > 0) { result = result*10; num = num*10; power_ten--; } while (power_ten < 0) { result = result/10; divider = divider*10; power_ten++; } if (num) result += FT_DivFix( num, divider ); if (sign) result = -result; *cursor = cur; return result; } static T1_Int t1_tocoordarray( T1_Byte* *cursor, T1_Byte* limit, T1_Int max_coords, T1_Short* coords ) { T1_Byte* cur = *cursor; T1_Int count = 0; T1_Byte c, ender; if (cur >= limit) goto Exit; /* check for the beginning of an array. If not, only one number will be read */ c = *cur; ender = 0; if (c == '[') ender = ']'; if (c == '{') ender = '}'; if (ender) cur++; /* now, read the coordinates */ for ( ; cur < limit; ) { /* skip whitespace in front of data */ for (;;) { c = *cur; if ( c != ' ' && c != '\t' ) break; cur++; if (cur >= limit) goto Exit; } if (count >= max_coords || c == ender) break; coords[count] = (T1_Short)(t1_tofixed(&cur,limit,0) >> 16); count++; if (!ender) break; } Exit: *cursor = cur; return count; } static T1_Int t1_tofixedarray( T1_Byte* *cursor, T1_Byte* limit, T1_Int max_values, T1_Fixed* values, T1_Int power_ten ) { T1_Byte* cur = *cursor; T1_Int count = 0; T1_Byte c, ender; if (cur >= limit) goto Exit; /* check for the beginning of an array. If not, only one number will be read */ c = *cur; ender = 0; if (c == '[') ender = ']'; if (c == '{') ender = '}'; if (ender) cur++; /* now, read the values */ for ( ; cur < limit; ) { /* skip whitespace in front of data */ for (;;) { c = *cur; if ( c != ' ' && c != '\t' ) break; cur++; if (cur >= limit) goto Exit; } if (count >= max_values || c == ender) break; values[count] = t1_tofixed(&cur,limit,power_ten); count++; if (!ender) break; } Exit: *cursor = cur; return count; } static T1_String* t1_tostring( T1_Byte* *cursor, T1_Byte* limit, FT_Memory memory ) { T1_Byte* cur = *cursor; T1_Int len = 0; T1_Int count; T1_String* result; FT_Error error; /* XXX : some stupid fonts have a "Notice" or "Copyright" string */ /* that simply doesn't begin with an opening parenthesis, even */ /* though they have a closing one !!! E.g. "amuncial.pfb" */ /* */ /* We must deal with these ill-fated cases there. Note that */ /* these fonts didn't work with the old Type 1 driver as the */ /* notice/copyright was not recognized as a valid string token */ /* and made the old token parser commit errors.. */ while ( cur < limit && (*cur == ' ' || *cur == '\t')) cur++; if (cur+1 >= limit) return 0; if (*cur == '(') cur++; /* skip the opening parenthesis, if there is one */ *cursor = cur; count = 0; /* then, count its length */ for ( ; cur < limit; cur++ ) { if (*cur == '(') count++; else if (*cur == ')') { count--; if (count < 0) break; } } len = cur - *cursor; if (cur >= limit || ALLOC(result,len+1)) return 0; /* now copy the string */ MEM_Copy( result, *cursor, len ); result[len] = '\0'; *cursor = cur; return result; } static int t1_tobool( T1_Byte* *cursor, T1_Byte* limit ) { T1_Byte* cur = *cursor; T1_Bool result = 0; /* return 1 if we find a "true", 0 otherwise */ if ( cur+3 < limit && cur[0] == 't' && cur[1] == 'r' && cur[2] == 'u' && cur[3] == 'e' ) { result = 1; cur += 5; } else if ( cur+4 < limit && cur[0] == 'f' && cur[1] == 'a' && cur[2] == 'l' && cur[3] == 's' && cur[4] == 'e' ) { result = 0; cur += 6; } *cursor = cur; return result; } LOCAL_FUNC T1_Long T1_ToInt ( T1_Parser* parser ) { return t1_toint( &parser->cursor, parser->limit ); } LOCAL_FUNC T1_Long T1_ToFixed( T1_Parser* parser, T1_Int power_ten ) { return t1_tofixed( &parser->cursor, parser->limit, power_ten ); } LOCAL_FUNC T1_Int T1_ToCoordArray( T1_Parser* parser, T1_Int max_coords, T1_Short* coords ) { return t1_tocoordarray( &parser->cursor, parser->limit, max_coords, coords ); } LOCAL_FUNC T1_Int T1_ToFixedArray( T1_Parser* parser, T1_Int max_values, T1_Fixed* values, T1_Int power_ten ) { return t1_tofixedarray( &parser->cursor, parser->limit, max_values, values, power_ten ); } LOCAL_FUNC T1_String* T1_ToString( T1_Parser* parser ) { return t1_tostring( &parser->cursor, parser->limit, parser->memory ); } LOCAL_FUNC T1_Bool T1_ToBool( T1_Parser* parser ) { return t1_tobool( &parser->cursor, parser->limit ); } static FT_Error read_pfb_tag( FT_Stream stream, T1_UShort *tag, T1_Long* size ) { FT_Error error; if (READ_UShort(*tag)) goto Exit; if (*tag == 0x8001 || *tag == 0x8002) { FT_Long asize; if (READ_ULong(asize)) goto Exit; /* swap between big and little endianness */ *size = ((asize & 0xFF000000) >> 24) | ((asize & 0x00FF0000) >> 8 ) | ((asize & 0x0000FF00) << 8 ) | ((asize & 0x000000FF) << 24); } Exit: return error; } LOCAL_FUNC T1_Error T1_New_Parser( T1_Parser* parser, FT_Stream stream, FT_Memory memory ) { FT_Error error; T1_UShort tag; T1_Long size; parser->stream = stream; parser->memory = memory; parser->base_len = 0; parser->base_dict = 0; parser->private_len = 0; parser->private_dict = 0; parser->in_pfb = 0; parser->in_memory = 0; parser->single_block = 0; parser->cursor = 0; parser->limit = 0; /******************************************************************/ /* */ /* Here's a short summary of what is going on : */ /* */ /* When creating a new Type 1 parser, we try to locate and */ /* load the base dictionary when this is possible (i.e. for */ /* .pfb files). Otherwise, we load the whole font in memory. */ /* */ /* When "loading" the base dictionary, we only setup pointers */ /* in the case of a memory-based stream. Otherwise, we allocate */ /* and load the base dict in it. */ /* */ /* parser->in_pfb is set when we are in a binary (".pfb") font */ /* parser->in_memory is set when we have a memory stream. */ /* */ /* try to compute the size of the base dictionary */ /* look for a Postscript binary file tag, i.e 0x8001 */ if ( FILE_Seek(0L) ) goto Exit; error = read_pfb_tag( stream, &tag, &size ); if (error) goto Exit; if (tag != 0x8001) { /* assume that this is a PFA file for now, an error will */ /* be produced later when more things are checked */ (void)FILE_Seek(0L); size = stream->size; } else parser->in_pfb = 1; /* now, try to load the "size" bytes of the "base" dictionary we */ /* found previously */ /* if it's a memory-based resource, set up pointers */ if ( !stream->read ) { parser->base_dict = (T1_Byte*)stream->base + stream->pos; parser->base_len = size; parser->in_memory = 1; /* check that the "size" field is valid */ if ( FILE_Skip(size) ) goto Exit; } else { /* read segment in memory */ if ( ALLOC( parser->base_dict, size ) || FILE_Read( parser->base_dict, size ) ) goto Exit; parser->base_len = size; } /* Now check font format, we must see a '%!PS-AdobeFont-1' */ /* or a '%!FontType' */ { if ( size <= 16 || ( strncmp( (const char*)parser->base_dict, "%!PS-AdobeFont-1", 16 ) && strncmp( (const char*)parser->base_dict, "%!FontType", 10 ) ) ) { FT_TRACE2(( "Not a Type1 font\n" )); error = FT_Err_Unknown_File_Format; } else { parser->cursor = parser->base_dict; parser->limit = parser->cursor + parser->base_len; } } Exit: if (error && !parser->in_memory) FREE( parser->base_dict ); return error; } LOCAL_FUNC void T1_Done_Parser( T1_Parser* parser ) { FT_Memory memory = parser->memory; /* always free the private dictionary */ FREE( parser->private_dict ); /* free the base dictionary only when we have a disk stream */ if (!parser->in_memory) FREE( parser->base_dict ); } /* return the value of an hexadecimal digit */ static int hexa_value( char c ) { unsigned int d; d = (unsigned int)(c-'0'); if ( d <= 9 ) return (int)d; d = (unsigned int)(c-'a'); if ( d <= 5 ) return (int)(d+10); d = (unsigned int)(c-'A'); if ( d <= 5 ) return (int)(d+10); return -1; } LOCAL_FUNC void T1_Decrypt( T1_Byte* buffer, T1_Int length, T1_UShort seed ) { while ( length > 0 ) { T1_Byte plain; plain = (*buffer ^ (seed >> 8)); seed = (*buffer+seed)*52845+22719; *buffer++ = plain; length--; } } LOCAL_FUNC T1_Error T1_Get_Private_Dict( T1_Parser* parser ) { FT_Stream stream = parser->stream; FT_Memory memory = parser->memory; FT_Error error = 0; T1_Long size; if (parser->in_pfb) { /* in the case of the PFB format, the private dictionary can be */ /* made of several segments. We thus first read the number of */ /* segments to compute the total size of the private dictionary */ /* then re-read them into memory.. */ T1_Long start_pos = FILE_Pos(); T1_UShort tag; T1_Long size; parser->private_len = 0; for (;;) { error = read_pfb_tag(stream, &tag, &size); if (error) goto Fail; if (tag != 0x8002) break; parser->private_len += size; if ( FILE_Skip(size) ) goto Fail; } /* Check that we have a private dictionary there */ /* and allocate private dictionary buffer */ if ( parser->private_len == 0 ) { FT_ERROR(( "T1.Open_Private: invalid private dictionary section\n" )); error = T1_Err_Invalid_File_Format; goto Fail; } if ( FILE_Seek( start_pos ) || ALLOC( parser->private_dict, parser->private_len ) ) goto Fail; parser->private_len = 0; for (;;) { error = read_pfb_tag( stream, &tag, &size ); if (error || tag != 0x8002) { error = 0; break; } if ( FILE_Read( parser->private_dict + parser->private_len, size ) ) goto Fail; parser->private_len += size; } } else { /* we have already "loaded" the whole PFA font file in memory */ /* if this is a memory resource, allocate a new block to hold */ /* the private dict. Otherwise, simply overwrite into the */ /* base dict block in the heap.. */ /* first of all, look at the "eexec" keyword */ FT_Byte* cur = parser->base_dict; FT_Byte* limit = cur + parser->base_len; FT_Byte c; for (;;) { c = cur[0]; if (c == 'e' && cur+9 < limit) /* 9 = 5 letters for 'eexec' + newline + 4 chars */ { if ( cur[1] == 'e' && cur[2] == 'x' && cur[3] == 'e' && cur[4] == 'c' ) { cur += 6; /* we skip the newling after the "eexec" */ /* XXX: Some fonts use DOS-linefeeds, i.e. \r\n, we need to skip */ /* the extra \n when we find it.. */ if (cur[0] == '\n') cur++; break; } } cur++; if (cur >= limit) { FT_ERROR(("T1.Open_Private: could not find 'eexec' keyword\n")); error = FT_Err_Invalid_File_Format; goto Exit; } } /* now determine wether where to write the _encrypted_ binary private */ /* dictionary. We overwrite the base dictionary for disk-based resources */ /* and allocate a new block otherwise */ size = parser->base_len - (cur-parser->base_dict); if ( parser->in_memory ) { /* note that we allocate one more byte to put a terminating '0' */ if (ALLOC( parser->private_dict, size+1 )) goto Fail; parser->private_len = size; } else { parser->single_block = 1; parser->private_dict = parser->base_dict; parser->private_len = size; parser->base_dict = 0; parser->base_len = 0; } /* now determine wether the private dictionary is encoded in binary */ /* or hexadecimal ASCII format.. */ /* and decode it accordingly */ /* we need to access the next 4 bytes (after the final \r following */ /* the 'eexec' keyword..) if they all are hexadecimal digits, then */ /*we have a case of ASCII storage.. */ if ( ( hexa_value( cur[0] ) | hexa_value( cur[1] ) | hexa_value( cur[2] ) | hexa_value( cur[3] ) ) < 0 ) { /* binary encoding - "simply" copy the private dict */ MEM_Copy( parser->private_dict, cur, size ); } else { /* ASCII hexadecimal encoding.. This blows goats !!.. */ T1_Byte* write; T1_Int count; write = parser->private_dict; count = 0; for ( ;cur < limit; cur++) { int hex1; /* check for newline */ if (cur[0] == '\r' || cur[0] == '\n') continue; /* exit if we have a non-hexadecimal digit that isn't a newline */ hex1 = hexa_value(cur[0]); if (hex1 < 0 || cur+1 >= limit) break; /* otherwise, store byte */ *write++ = (hex1 << 4) | hexa_value(cur[1]); count++; cur++; } /* put a safeguard */ parser->private_len = write - parser->private_dict; *write++ = 0; } } /* we now decrypt the encoded binary private dictionary */ T1_Decrypt( parser->private_dict, parser->private_len, 55665 ); parser->cursor = parser->private_dict; parser->limit = parser->cursor + parser->private_len; Fail: Exit: return error; }