498 lines
16 KiB
C
498 lines
16 KiB
C
/***************************************************************************/
|
|
/* */
|
|
/* t1parse.c */
|
|
/* */
|
|
/* Type 1 parser (body). */
|
|
/* */
|
|
/* Copyright 1996-2005, 2008, 2009, 2012, 2013 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 <ft2build.h>
|
|
#include FT_INTERNAL_DEBUG_H
|
|
#include FT_INTERNAL_STREAM_H
|
|
#include FT_INTERNAL_POSTSCRIPT_AUX_H
|
|
|
|
#include "t1parse.h"
|
|
|
|
#include "t1errors.h"
|
|
|
|
|
|
/*************************************************************************/
|
|
/* */
|
|
/* 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 *****/
|
|
/***** *****/
|
|
/*************************************************************************/
|
|
/*************************************************************************/
|
|
/*************************************************************************/
|
|
|
|
|
|
/* see Adobe Technical Note 5040.Download_Fonts.pdf */
|
|
|
|
static FT_Error
|
|
read_pfb_tag( FT_Stream stream,
|
|
FT_UShort *atag,
|
|
FT_ULong *asize )
|
|
{
|
|
FT_Error error;
|
|
FT_UShort tag;
|
|
FT_ULong size;
|
|
|
|
|
|
*atag = 0;
|
|
*asize = 0;
|
|
|
|
if ( !FT_READ_USHORT( tag ) )
|
|
{
|
|
if ( tag == 0x8001U || tag == 0x8002U )
|
|
{
|
|
if ( !FT_READ_ULONG_LE( size ) )
|
|
*asize = size;
|
|
}
|
|
|
|
*atag = tag;
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
|
|
static FT_Error
|
|
check_type1_format( FT_Stream stream,
|
|
const char* header_string,
|
|
size_t header_length )
|
|
{
|
|
FT_Error error;
|
|
FT_UShort tag;
|
|
FT_ULong dummy;
|
|
|
|
|
|
if ( FT_STREAM_SEEK( 0 ) )
|
|
goto Exit;
|
|
|
|
error = read_pfb_tag( stream, &tag, &dummy );
|
|
if ( error )
|
|
goto Exit;
|
|
|
|
/* We assume that the first segment in a PFB is always encoded as */
|
|
/* text. This might be wrong (and the specification doesn't insist */
|
|
/* on that), but we have never seen a counterexample. */
|
|
if ( tag != 0x8001U && FT_STREAM_SEEK( 0 ) )
|
|
goto Exit;
|
|
|
|
if ( !FT_FRAME_ENTER( header_length ) )
|
|
{
|
|
error = FT_Err_Ok;
|
|
|
|
if ( ft_memcmp( stream->cursor, header_string, header_length ) != 0 )
|
|
error = FT_THROW( Unknown_File_Format );
|
|
|
|
FT_FRAME_EXIT();
|
|
}
|
|
|
|
Exit:
|
|
return error;
|
|
}
|
|
|
|
|
|
FT_LOCAL_DEF( FT_Error )
|
|
T1_New_Parser( T1_Parser parser,
|
|
FT_Stream stream,
|
|
FT_Memory memory,
|
|
PSAux_Service psaux )
|
|
{
|
|
FT_Error error;
|
|
FT_UShort tag;
|
|
FT_ULong size;
|
|
|
|
|
|
psaux->ps_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;
|
|
|
|
/* check the header format */
|
|
error = check_type1_format( stream, "%!PS-AdobeFont", 14 );
|
|
if ( error )
|
|
{
|
|
if ( FT_ERR_NEQ( error, Unknown_File_Format ) )
|
|
goto Exit;
|
|
|
|
error = check_type1_format( stream, "%!FontType", 10 );
|
|
if ( error )
|
|
{
|
|
FT_TRACE2(( " not a Type 1 font\n" ));
|
|
goto Exit;
|
|
}
|
|
}
|
|
|
|
/******************************************************************/
|
|
/* */
|
|
/* 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 ( FT_STREAM_SEEK( 0L ) )
|
|
goto Exit;
|
|
|
|
error = read_pfb_tag( stream, &tag, &size );
|
|
if ( error )
|
|
goto Exit;
|
|
|
|
if ( tag != 0x8001U )
|
|
{
|
|
/* assume that this is a PFA file for now; an error will */
|
|
/* be produced later when more things are checked */
|
|
if ( FT_STREAM_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 ( FT_STREAM_SKIP( size ) )
|
|
goto Exit;
|
|
}
|
|
else
|
|
{
|
|
/* read segment in memory -- this is clumsy, but so does the format */
|
|
if ( FT_ALLOC( parser->base_dict, size ) ||
|
|
FT_STREAM_READ( parser->base_dict, size ) )
|
|
goto Exit;
|
|
parser->base_len = size;
|
|
}
|
|
|
|
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 )
|
|
FT_FREE( parser->base_dict );
|
|
|
|
return error;
|
|
}
|
|
|
|
|
|
FT_LOCAL_DEF( void )
|
|
T1_Finalize_Parser( T1_Parser parser )
|
|
{
|
|
FT_Memory memory = parser->root.memory;
|
|
|
|
|
|
/* always free the private dictionary */
|
|
FT_FREE( parser->private_dict );
|
|
|
|
/* free the base dictionary only when we have a disk stream */
|
|
if ( !parser->in_memory )
|
|
FT_FREE( parser->base_dict );
|
|
|
|
parser->root.funcs.done( &parser->root );
|
|
}
|
|
|
|
|
|
FT_LOCAL_DEF( FT_Error )
|
|
T1_Get_Private_Dict( T1_Parser parser,
|
|
PSAux_Service psaux )
|
|
{
|
|
FT_Stream stream = parser->stream;
|
|
FT_Memory memory = parser->root.memory;
|
|
FT_Error error = FT_Err_Ok;
|
|
FT_ULong 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 = FT_STREAM_POS();
|
|
FT_UShort tag;
|
|
|
|
|
|
parser->private_len = 0;
|
|
for (;;)
|
|
{
|
|
error = read_pfb_tag( stream, &tag, &size );
|
|
if ( error )
|
|
goto Fail;
|
|
|
|
if ( tag != 0x8002U )
|
|
break;
|
|
|
|
parser->private_len += size;
|
|
|
|
if ( FT_STREAM_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:"
|
|
" invalid private dictionary section\n" ));
|
|
error = FT_THROW( Invalid_File_Format );
|
|
goto Fail;
|
|
}
|
|
|
|
if ( FT_STREAM_SEEK( start_pos ) ||
|
|
FT_ALLOC( parser->private_dict, parser->private_len ) )
|
|
goto Fail;
|
|
|
|
parser->private_len = 0;
|
|
for (;;)
|
|
{
|
|
error = read_pfb_tag( stream, &tag, &size );
|
|
if ( error || tag != 0x8002U )
|
|
{
|
|
error = FT_Err_Ok;
|
|
break;
|
|
}
|
|
|
|
if ( FT_STREAM_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;
|
|
|
|
|
|
Again:
|
|
for (;;)
|
|
{
|
|
c = cur[0];
|
|
if ( c == 'e' && cur + 9 < limit ) /* 9 = 5 letters for `eexec' + */
|
|
/* whitespace + 4 chars */
|
|
{
|
|
if ( cur[1] == 'e' &&
|
|
cur[2] == 'x' &&
|
|
cur[3] == 'e' &&
|
|
cur[4] == 'c' )
|
|
break;
|
|
}
|
|
cur++;
|
|
if ( cur >= limit )
|
|
{
|
|
FT_ERROR(( "T1_Get_Private_Dict:"
|
|
" could not find `eexec' keyword\n" ));
|
|
error = FT_THROW( Invalid_File_Format );
|
|
goto Exit;
|
|
}
|
|
}
|
|
|
|
/* check whether `eexec' was real -- it could be in a comment */
|
|
/* or string (as e.g. in u003043t.gsf from ghostscript) */
|
|
|
|
parser->root.cursor = parser->base_dict;
|
|
/* set limit to `eexec' + whitespace + 4 characters */
|
|
parser->root.limit = cur + 10;
|
|
|
|
cur = parser->root.cursor;
|
|
limit = parser->root.limit;
|
|
|
|
while ( cur < limit )
|
|
{
|
|
if ( *cur == 'e' && ft_strncmp( (char*)cur, "eexec", 5 ) == 0 )
|
|
goto Found;
|
|
|
|
T1_Skip_PS_Token( parser );
|
|
if ( parser->root.error )
|
|
break;
|
|
T1_Skip_Spaces ( parser );
|
|
cur = parser->root.cursor;
|
|
}
|
|
|
|
/* we haven't found the correct `eexec'; go back and continue */
|
|
/* searching */
|
|
|
|
cur = limit;
|
|
limit = parser->base_dict + parser->base_len;
|
|
goto Again;
|
|
|
|
/* 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 */
|
|
|
|
Found:
|
|
parser->root.limit = parser->base_dict + parser->base_len;
|
|
|
|
T1_Skip_PS_Token( parser );
|
|
cur = parser->root.cursor;
|
|
limit = parser->root.limit;
|
|
|
|
/* according to the Type1 spec, the first cipher byte must not be */
|
|
/* an ASCII whitespace character code (blank, tab, carriage return */
|
|
/* or line feed). We have seen Type 1 fonts with two line feed */
|
|
/* characters... So skip now all whitespace character codes. */
|
|
while ( cur < limit &&
|
|
( *cur == ' ' ||
|
|
*cur == '\t' ||
|
|
*cur == '\r' ||
|
|
*cur == '\n' ) )
|
|
++cur;
|
|
if ( cur >= limit )
|
|
{
|
|
FT_ERROR(( "T1_Get_Private_Dict:"
|
|
" `eexec' not properly terminated\n" ));
|
|
error = FT_THROW( Invalid_File_Format );
|
|
goto Exit;
|
|
}
|
|
|
|
size = (FT_ULong)( parser->base_len - ( cur - parser->base_dict ) );
|
|
|
|
if ( parser->in_memory )
|
|
{
|
|
/* note that we allocate one more byte to put a terminating `0' */
|
|
if ( FT_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 whitespace */
|
|
/* following the `eexec' keyword); if they all are hexadecimal */
|
|
/* digits, then we have a case of ASCII storage */
|
|
|
|
if ( cur + 3 < limit &&
|
|
ft_isxdigit( cur[0] ) && ft_isxdigit( cur[1] ) &&
|
|
ft_isxdigit( cur[2] ) && ft_isxdigit( cur[3] ) )
|
|
{
|
|
/* ASCII hexadecimal encoding */
|
|
FT_Long len;
|
|
|
|
|
|
parser->root.cursor = cur;
|
|
(void)psaux->ps_parser_funcs->to_bytes( &parser->root,
|
|
parser->private_dict,
|
|
parser->private_len,
|
|
&len,
|
|
0 );
|
|
parser->private_len = len;
|
|
|
|
/* put a safeguard */
|
|
parser->private_dict[len] = '\0';
|
|
}
|
|
else
|
|
/* binary encoding -- copy the private dict */
|
|
FT_MEM_MOVE( parser->private_dict, cur, size );
|
|
}
|
|
|
|
/* we now decrypt the encoded binary private dictionary */
|
|
psaux->t1_decrypt( parser->private_dict, parser->private_len, 55665U );
|
|
|
|
if ( parser->private_len < 4 )
|
|
{
|
|
FT_ERROR(( "T1_Get_Private_Dict:"
|
|
" invalid private dictionary section\n" ));
|
|
error = FT_THROW( Invalid_File_Format );
|
|
goto Fail;
|
|
}
|
|
|
|
/* replace the four random bytes at the beginning with whitespace */
|
|
parser->private_dict[0] = ' ';
|
|
parser->private_dict[1] = ' ';
|
|
parser->private_dict[2] = ' ';
|
|
parser->private_dict[3] = ' ';
|
|
|
|
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 */
|