cidparse.c revision bebc7b11c52c00e8edfaf2ba38ca25d135404a1c 
1/***************************************************************************/
2/*                                                                         */
3/*  cidparse.c                                                             */
4/*                                                                         */
5/*    CID-keyed Type1 parser (body).                                       */
6/*                                                                         */
7/*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007 by             */
8/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
9/*                                                                         */
10/*  This file is part of the FreeType project, and may only be used,       */
11/*  modified, and distributed under the terms of the FreeType project      */
12/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
13/*  this file you indicate that you have read the license and              */
14/*  understand and accept it fully.                                        */
15/*                                                                         */
16/***************************************************************************/
17
18
19#include <ft2build.h>
20#include FT_INTERNAL_DEBUG_H
21#include FT_INTERNAL_CALC_H
22#include FT_INTERNAL_OBJECTS_H
23#include FT_INTERNAL_STREAM_H
24
25#include "cidparse.h"
26
27#include "ciderrs.h"
28
29
30  /*************************************************************************/
31  /*                                                                       */
32  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
33  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
34  /* messages during execution.                                            */
35  /*                                                                       */
36#undef  FT_COMPONENT
37#define FT_COMPONENT  trace_cidparse
38
39
40  /*************************************************************************/
41  /*************************************************************************/
42  /*************************************************************************/
43  /*****                                                               *****/
44  /*****                    INPUT STREAM PARSER                        *****/
45  /*****                                                               *****/
46  /*************************************************************************/
47  /*************************************************************************/
48  /*************************************************************************/
49
50
51  FT_LOCAL_DEF( FT_Error )
52  cid_parser_new( CID_Parser*    parser,
53                  FT_Stream      stream,
54                  FT_Memory      memory,
55                  PSAux_Service  psaux )
56  {
57    FT_Error  error;
58    FT_ULong  base_offset, offset, ps_len;
59    FT_Byte   *cur, *limit;
60    FT_Byte   *arg1, *arg2;
61
62
63    FT_MEM_ZERO( parser, sizeof ( *parser ) );
64    psaux->ps_parser_funcs->init( &parser->root, 0, 0, memory );
65
66    parser->stream = stream;
67
68    base_offset = FT_STREAM_POS();
69
70    /* first of all, check the font format in the header */
71    if ( FT_FRAME_ENTER( 31 ) )
72      goto Exit;
73
74    if ( ft_strncmp( (char *)stream->cursor,
75                     "%!PS-Adobe-3.0 Resource-CIDFont", 31 ) )
76    {
77      FT_TRACE2(( "[not a valid CID-keyed font]\n" ));
78      error = CID_Err_Unknown_File_Format;
79    }
80
81    FT_FRAME_EXIT();
82    if ( error )
83      goto Exit;
84
85  Again:
86    /* now, read the rest of the file until we find */
87    /* `StartData' or `/sfnts'                      */
88    {
89      FT_Byte   buffer[256 + 10];
90      FT_Int    read_len = 256 + 10;
91      FT_Byte*  p        = buffer;
92
93
94      for ( offset = (FT_ULong)FT_STREAM_POS(); ; offset += 256 )
95      {
96        FT_Int  stream_len;
97
98
99        stream_len = stream->size - FT_STREAM_POS();
100        if ( stream_len == 0 )
101          goto Exit;
102
103        read_len = FT_MIN( read_len, stream_len );
104        if ( FT_STREAM_READ( p, read_len ) )
105          goto Exit;
106
107        if ( read_len < 256 )
108          p[read_len]  = '\0';
109
110        limit = p + read_len - 10;
111
112        for ( p = buffer; p < limit; p++ )
113        {
114          if ( p[0] == 'S' && ft_strncmp( (char*)p, "StartData", 9 ) == 0 )
115          {
116            /* save offset of binary data after `StartData' */
117            offset += p - buffer + 10;
118            goto Found;
119          }
120          else if ( p[1] == 's' && ft_strncmp( (char*)p, "/sfnts", 6 ) == 0 )
121          {
122            offset += p - buffer + 7;
123            goto Found;
124          }
125        }
126
127        FT_MEM_MOVE( buffer, p, 10 );
128        read_len = 256;
129        p = buffer + 10;
130      }
131    }
132
133  Found:
134    /* We have found the start of the binary data or the `/sfnts' token. */
135    /* Now rewind and extract the frame corresponding to this PostScript */
136    /* section.                                                          */
137
138    ps_len = offset - base_offset;
139    if ( FT_STREAM_SEEK( base_offset )                  ||
140         FT_FRAME_EXTRACT( ps_len, parser->postscript ) )
141      goto Exit;
142
143    parser->data_offset    = offset;
144    parser->postscript_len = ps_len;
145    parser->root.base      = parser->postscript;
146    parser->root.cursor    = parser->postscript;
147    parser->root.limit     = parser->root.cursor + ps_len;
148    parser->num_dict       = -1;
149
150    /* Finally, we check whether `StartData' or `/sfnts' was real --  */
151    /* it could be in a comment or string.  We also get the arguments */
152    /* of `StartData' to find out whether the data is represented in  */
153    /* binary or hex format.                                          */
154
155    arg1 = parser->root.cursor;
156    cid_parser_skip_PS_token( parser );
157    cid_parser_skip_spaces  ( parser );
158    arg2 = parser->root.cursor;
159    cid_parser_skip_PS_token( parser );
160    cid_parser_skip_spaces  ( parser );
161
162    limit = parser->root.limit;
163    cur   = parser->root.cursor;
164
165    while ( cur < limit )
166    {
167      if ( parser->root.error )
168      {
169        error = parser->root.error;
170        goto Exit;
171      }
172
173      if ( cur[0] == 'S' && ft_strncmp( (char*)cur, "StartData", 9 ) == 0 )
174      {
175        if ( ft_strncmp( (char*)arg1, "(Hex)", 5 ) == 0 )
176          parser->binary_length = ft_atol( (const char *)arg2 );
177
178        limit = parser->root.limit;
179        cur   = parser->root.cursor;
180        goto Exit;
181      }
182      else if ( cur[1] == 's' && ft_strncmp( (char*)cur, "/sfnts", 6 ) == 0 )
183      {
184        FT_TRACE2(( "cid_parser_new: cannot handle Type 11 fonts\n" ));
185        error = CID_Err_Unknown_File_Format;
186        goto Exit;
187      }
188
189      cid_parser_skip_PS_token( parser );
190      cid_parser_skip_spaces  ( parser );
191      arg1 = arg2;
192      arg2 = cur;
193      cur  = parser->root.cursor;
194    }
195
196    /* we haven't found the correct `StartData'; go back and continue */
197    /* searching                                                      */
198    FT_FRAME_RELEASE( parser->postscript );
199    if ( !FT_STREAM_SEEK( offset ) )
200      goto Again;
201
202  Exit:
203    return error;
204  }
205
206
207  FT_LOCAL_DEF( void )
208  cid_parser_done( CID_Parser*  parser )
209  {
210    /* always free the private dictionary */
211    if ( parser->postscript )
212    {
213      FT_Stream  stream = parser->stream;
214
215
216      FT_FRAME_RELEASE( parser->postscript );
217    }
218    parser->root.funcs.done( &parser->root );
219  }
220
221
222/* END */
223