cidparse.c revision 059bc335ce42220b222763379e89d0cbf2b949eb 
1/***************************************************************************/
2/*                                                                         */
3/*  cidparse.c                                                             */
4/*                                                                         */
5/*    CID-keyed Type1 parser (body).                                       */
6/*                                                                         */
7/*  Copyright 1996-2007, 2009, 2013 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_OBJECTS_H
22#include FT_INTERNAL_STREAM_H
23
24#include "cidparse.h"
25
26#include "ciderrs.h"
27
28
29  /*************************************************************************/
30  /*                                                                       */
31  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
32  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
33  /* messages during execution.                                            */
34  /*                                                                       */
35#undef  FT_COMPONENT
36#define FT_COMPONENT  trace_cidparse
37
38
39  /*************************************************************************/
40  /*************************************************************************/
41  /*************************************************************************/
42  /*****                                                               *****/
43  /*****                    INPUT STREAM PARSER                        *****/
44  /*****                                                               *****/
45  /*************************************************************************/
46  /*************************************************************************/
47  /*************************************************************************/
48
49
50  FT_LOCAL_DEF( FT_Error )
51  cid_parser_new( CID_Parser*    parser,
52                  FT_Stream      stream,
53                  FT_Memory      memory,
54                  PSAux_Service  psaux )
55  {
56    FT_Error  error;
57    FT_ULong  base_offset, offset, ps_len;
58    FT_Byte   *cur, *limit;
59    FT_Byte   *arg1, *arg2;
60
61
62    FT_MEM_ZERO( parser, sizeof ( *parser ) );
63    psaux->ps_parser_funcs->init( &parser->root, 0, 0, memory );
64
65    parser->stream = stream;
66
67    base_offset = FT_STREAM_POS();
68
69    /* first of all, check the font format in the header */
70    if ( FT_FRAME_ENTER( 31 ) )
71      goto Exit;
72
73    if ( ft_strncmp( (char *)stream->cursor,
74                     "%!PS-Adobe-3.0 Resource-CIDFont", 31 ) )
75    {
76      FT_TRACE2(( "  not a CID-keyed font\n" ));
77      error = FT_THROW( Unknown_File_Format );
78    }
79
80    FT_FRAME_EXIT();
81    if ( error )
82      goto Exit;
83
84  Again:
85    /* now, read the rest of the file until we find */
86    /* `StartData' or `/sfnts'                      */
87    {
88      FT_Byte   buffer[256 + 10];
89      FT_Long   read_len = 256 + 10; /* same as signed FT_Stream->size */
90      FT_Byte*  p        = buffer;
91
92
93      for ( offset = FT_STREAM_POS(); ; offset += 256 )
94      {
95        FT_Long  stream_len; /* same as signed FT_Stream->size */
96
97
98        stream_len = stream->size - FT_STREAM_POS();
99        if ( stream_len == 0 )
100        {
101          FT_TRACE2(( "cid_parser_new: no `StartData' keyword found\n" ));
102          error = FT_THROW( Invalid_File_Format );
103          goto Exit;
104        }
105
106        read_len = FT_MIN( read_len, stream_len );
107        if ( FT_STREAM_READ( p, read_len ) )
108          goto Exit;
109
110        if ( read_len < 256 )
111          p[read_len]  = '\0';
112
113        limit = p + read_len - 10;
114
115        for ( p = buffer; p < limit; p++ )
116        {
117          if ( p[0] == 'S' && ft_strncmp( (char*)p, "StartData", 9 ) == 0 )
118          {
119            /* save offset of binary data after `StartData' */
120            offset += p - buffer + 10;
121            goto Found;
122          }
123          else if ( p[1] == 's' && ft_strncmp( (char*)p, "/sfnts", 6 ) == 0 )
124          {
125            offset += p - buffer + 7;
126            goto Found;
127          }
128        }
129
130        FT_MEM_MOVE( buffer, p, 10 );
131        read_len = 256;
132        p = buffer + 10;
133      }
134    }
135
136  Found:
137    /* We have found the start of the binary data or the `/sfnts' token. */
138    /* Now rewind and extract the frame corresponding to this PostScript */
139    /* section.                                                          */
140
141    ps_len = offset - base_offset;
142    if ( FT_STREAM_SEEK( base_offset )                  ||
143         FT_FRAME_EXTRACT( ps_len, parser->postscript ) )
144      goto Exit;
145
146    parser->data_offset    = offset;
147    parser->postscript_len = ps_len;
148    parser->root.base      = parser->postscript;
149    parser->root.cursor    = parser->postscript;
150    parser->root.limit     = parser->root.cursor + ps_len;
151    parser->num_dict       = -1;
152
153    /* Finally, we check whether `StartData' or `/sfnts' was real --  */
154    /* it could be in a comment or string.  We also get the arguments */
155    /* of `StartData' to find out whether the data is represented in  */
156    /* binary or hex format.                                          */
157
158    arg1 = parser->root.cursor;
159    cid_parser_skip_PS_token( parser );
160    cid_parser_skip_spaces  ( parser );
161    arg2 = parser->root.cursor;
162    cid_parser_skip_PS_token( parser );
163    cid_parser_skip_spaces  ( parser );
164
165    limit = parser->root.limit;
166    cur   = parser->root.cursor;
167
168    while ( cur < limit )
169    {
170      if ( parser->root.error )
171      {
172        error = parser->root.error;
173        goto Exit;
174      }
175
176      if ( cur[0] == 'S' && ft_strncmp( (char*)cur, "StartData", 9 ) == 0 )
177      {
178        if ( ft_strncmp( (char*)arg1, "(Hex)", 5 ) == 0 )
179          parser->binary_length = ft_atol( (const char *)arg2 );
180
181        limit = parser->root.limit;
182        cur   = parser->root.cursor;
183        goto Exit;
184      }
185      else if ( cur[1] == 's' && ft_strncmp( (char*)cur, "/sfnts", 6 ) == 0 )
186      {
187        FT_TRACE2(( "cid_parser_new: cannot handle Type 11 fonts\n" ));
188        error = FT_THROW( Unknown_File_Format );
189        goto Exit;
190      }
191
192      cid_parser_skip_PS_token( parser );
193      cid_parser_skip_spaces  ( parser );
194      arg1 = arg2;
195      arg2 = cur;
196      cur  = parser->root.cursor;
197    }
198
199    /* we haven't found the correct `StartData'; go back and continue */
200    /* searching                                                      */
201    FT_FRAME_RELEASE( parser->postscript );
202    if ( !FT_STREAM_SEEK( offset ) )
203      goto Again;
204
205  Exit:
206    return error;
207  }
208
209
210  FT_LOCAL_DEF( void )
211  cid_parser_done( CID_Parser*  parser )
212  {
213    /* always free the private dictionary */
214    if ( parser->postscript )
215    {
216      FT_Stream  stream = parser->stream;
217
218
219      FT_FRAME_RELEASE( parser->postscript );
220    }
221    parser->root.funcs.done( &parser->root );
222  }
223
224
225/* END */
226