| /***************************************************************************/ |
| /* */ |
| /* t1parse.c */ |
| /* */ |
| /* Type 1 parser (body). */ |
| /* */ |
| /* Copyright 1996-2000 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 <freetype/internal/t1errors.h> |
| #include <freetype/internal/psaux.h> |
| |
| #ifdef FT_FLAT_COMPILE |
| |
| #include "t1parse.h" |
| |
| #else |
| |
| #include <type1/t1parse.h> |
| |
| #endif |
| |
| |
| #include <string.h> /* for strncmp() */ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ |
| /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ |
| /* messages during execution. */ |
| /* */ |
| #undef FT_COMPONENT |
| #define FT_COMPONENT trace_t1parse |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** INPUT STREAM PARSER *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| #define IS_T1_WHITESPACE( c ) ( (c) == ' ' || (c) == '\t' ) |
| #define IS_T1_LINESPACE( c ) ( (c) == '\r' || (c) == '\n' ) |
| |
| #define IS_T1_SPACE( c ) ( IS_T1_WHITESPACE( c ) || IS_T1_LINESPACE( c ) ) |
| |
| |
| typedef struct PFB_Tag_ |
| { |
| FT_UShort tag; |
| FT_Long size; |
| |
| } PFB_Tag; |
| |
| |
| #undef FT_STRUCTURE |
| #define FT_STRUCTURE PFB_Tag |
| |
| |
| static |
| const FT_Frame_Field pfb_tag_fields[] = |
| { |
| FT_FRAME_START( 6 ), |
| FT_FRAME_USHORT ( tag ), |
| FT_FRAME_LONG_LE( size ), |
| FT_FRAME_END |
| }; |
| |
| |
| static |
| FT_Error read_pfb_tag( FT_Stream stream, |
| FT_UShort* tag, |
| FT_Long* size ) |
| { |
| FT_Error error; |
| PFB_Tag head; |
| |
| |
| *tag = 0; |
| *size = 0; |
| if ( !READ_Fields( pfb_tag_fields, &head ) ) |
| { |
| if ( head.tag == 0x8001 || head.tag == 0x8002 ) |
| { |
| *tag = head.tag; |
| *size = head.size; |
| } |
| } |
| return error; |
| } |
| |
| |
| LOCAL_FUNC |
| FT_Error T1_New_Parser( T1_ParserRec* parser, |
| FT_Stream stream, |
| FT_Memory memory, |
| PSAux_Interface* psaux ) |
| { |
| FT_Error error; |
| FT_UShort tag; |
| FT_Long size; |
| |
| |
| psaux->t1_parser_funcs->init( &parser->root,0, 0, memory ); |
| |
| parser->stream = stream; |
| 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; |
| |
| /******************************************************************/ |
| /* */ |
| /* Here a short summary of what is going on: */ |
| /* */ |
| /* When creating a new Type 1 parser, we try to locate and load */ |
| /* the base dictionary if this is possible (i.e. for PFB */ |
| /* files). Otherwise, we load the whole font into 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 dictionary in it. */ |
| /* */ |
| /* parser->in_pfb is set if we are in a binary (".pfb") font. */ |
| /* parser->in_memory is set if 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 */ |
| if ( FILE_Seek( 0L ) ) |
| goto Exit; |
| size = stream->size; |
| } |
| else |
| parser->in_pfb = 1; |
| |
| /* now, try to load `size' bytes of the `base' dictionary we */ |
| /* found previously */ |
| |
| /* if it is a memory-based resource, set up pointers */ |
| if ( !stream->read ) |
| { |
| parser->base_dict = (FT_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 `%!PS-AdobeFont-1' */ |
| /* or `%!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->root.base = parser->base_dict; |
| parser->root.cursor = parser->base_dict; |
| parser->root.limit = parser->root.cursor + parser->base_len; |
| } |
| } |
| |
| Exit: |
| if ( error && !parser->in_memory ) |
| FREE( parser->base_dict ); |
| |
| return error; |
| } |
| |
| |
| LOCAL_FUNC |
| void T1_Done_Parser( T1_ParserRec* parser ) |
| { |
| FT_Memory memory = parser->root.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 ); |
| |
| parser->root.funcs.done( &parser->root ); |
| } |
| |
| |
| /* 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( FT_Byte* buffer, |
| FT_Int length, |
| FT_UShort seed ) |
| { |
| while ( length > 0 ) |
| { |
| FT_Byte plain; |
| |
| |
| plain = ( *buffer ^ ( seed >> 8 ) ); |
| seed = ( *buffer + seed ) * 52845 + 22719; |
| *buffer++ = plain; |
| length--; |
| } |
| } |
| |
| |
| LOCAL_FUNC |
| FT_Error T1_Get_Private_Dict( T1_ParserRec* parser ) |
| { |
| FT_Stream stream = parser->stream; |
| FT_Memory memory = parser->root.memory; |
| FT_Error error = 0; |
| FT_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. */ |
| FT_Long start_pos = FILE_Pos(); |
| FT_UShort tag; |
| |
| |
| 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_Get_Private_Dict:" )); |
| FT_ERROR(( " 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 = FT_Err_Ok; |
| 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 into memory; */ |
| /* if this is a memory resource, allocate a new block to hold */ |
| /* the private dict. Otherwise, simply overwrite into the base */ |
| /* dictionary 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 if we find it */ |
| if ( cur[0] == '\n' ) |
| cur++; |
| |
| break; |
| } |
| } |
| cur++; |
| if ( cur >= limit ) |
| { |
| FT_ERROR(( "T1_Get_Private_Dict:" )); |
| FT_ERROR(( " could not find `eexec' keyword\n" )); |
| error = T1_Err_Invalid_File_Format; |
| goto Exit; |
| } |
| } |
| |
| /* now determine 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 whether the private dictionary is encoded in binary */ |
| /* or hexadecimal ASCII format -- 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 */ |
| |
| FT_Byte* write; |
| FT_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->root.base = parser->private_dict; |
| parser->root.cursor = parser->private_dict; |
| parser->root.limit = parser->root.cursor + parser->private_len; |
| |
| Fail: |
| Exit: |
| return error; |
| } |
| |
| |
| /* END */ |