1 /****************************************************************************
2 *
3 * ftsystem.c
4 *
5 * ANSI-specific FreeType low-level system interface (body).
6 *
7 * Copyright (C) 1996-2023 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 *
20 * This file contains the default interface used by FreeType to access
21 * low-level, i.e. memory management, i/o access as well as thread
22 * synchronisation. It can be replaced by user-specific routines if
23 * necessary.
24 *
25 */
26
27
28 #include <ft2build.h>
29 #include FT_CONFIG_CONFIG_H
30 #include <freetype/internal/ftdebug.h>
31 #include <freetype/internal/ftstream.h>
32 #include <freetype/ftsystem.h>
33 #include <freetype/fterrors.h>
34 #include <freetype/fttypes.h>
35
36
37 /**************************************************************************
38 *
39 * MEMORY MANAGEMENT INTERFACE
40 *
41 */
42
43 /**************************************************************************
44 *
45 * It is not necessary to do any error checking for the
46 * allocation-related functions. This will be done by the higher level
47 * routines like ft_mem_alloc() or ft_mem_realloc().
48 *
49 */
50
51
52 /**************************************************************************
53 *
54 * @Function:
55 * ft_alloc
56 *
57 * @Description:
58 * The memory allocation function.
59 *
60 * @Input:
61 * memory ::
62 * A pointer to the memory object.
63 *
64 * size ::
65 * The requested size in bytes.
66 *
67 * @Return:
68 * The address of newly allocated block.
69 */
70 FT_CALLBACK_DEF( void* )
71 ft_alloc( FT_Memory memory,
72 long size )
73 {
74 FT_UNUSED( memory );
75
76 return ft_smalloc( (size_t)size );
77 }
78
79
80 /**************************************************************************
81 *
82 * @Function:
83 * ft_realloc
84 *
85 * @Description:
86 * The memory reallocation function.
87 *
88 * @Input:
89 * memory ::
90 * A pointer to the memory object.
91 *
92 * cur_size ::
93 * The current size of the allocated memory block.
94 *
95 * new_size ::
96 * The newly requested size in bytes.
97 *
98 * block ::
99 * The current address of the block in memory.
100 *
101 * @Return:
102 * The address of the reallocated memory block.
103 */
104 FT_CALLBACK_DEF( void* )
105 ft_realloc( FT_Memory memory,
106 long cur_size,
107 long new_size,
108 void* block )
109 {
110 FT_UNUSED( memory );
111 FT_UNUSED( cur_size );
112
113 return ft_srealloc( block, (size_t)new_size );
114 }
115
116
117 /**************************************************************************
118 *
119 * @Function:
120 * ft_free
121 *
122 * @Description:
123 * The memory release function.
124 *
125 * @Input:
126 * memory ::
127 * A pointer to the memory object.
128 *
129 * block ::
130 * The address of block in memory to be freed.
131 */
132 FT_CALLBACK_DEF( void )
133 ft_free( FT_Memory memory,
134 void* block )
135 {
136 FT_UNUSED( memory );
137
138 ft_sfree( block );
139 }
140
141
142 /**************************************************************************
143 *
144 * RESOURCE MANAGEMENT INTERFACE
145 *
146 */
147
148 #ifndef FT_CONFIG_OPTION_DISABLE_STREAM_SUPPORT
149
150 /**************************************************************************
151 *
152 * The macro FT_COMPONENT is used in trace mode. It is an implicit
153 * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
154 * messages during execution.
155 */
156 #undef FT_COMPONENT
157 #define FT_COMPONENT io
158
159 /* We use the macro STREAM_FILE for convenience to extract the */
160 /* system-specific stream handle from a given FreeType stream object */
161 #define STREAM_FILE( stream ) ( (FT_FILE*)stream->descriptor.pointer )
162
163
164 /**************************************************************************
165 *
166 * @Function:
167 * ft_ansi_stream_close
168 *
169 * @Description:
170 * The function to close a stream.
171 *
172 * @Input:
173 * stream ::
174 * A pointer to the stream object.
175 */
176 FT_CALLBACK_DEF( void )
177 ft_ansi_stream_close( FT_Stream stream )
178 {
179 ft_fclose( STREAM_FILE( stream ) );
180
181 stream->descriptor.pointer = NULL;
182 stream->size = 0;
183 stream->base = NULL;
184 }
185
186
187 /**************************************************************************
188 *
189 * @Function:
190 * ft_ansi_stream_io
191 *
192 * @Description:
193 * The function to open a stream.
194 *
195 * @Input:
196 * stream ::
197 * A pointer to the stream object.
198 *
199 * offset ::
200 * The position in the data stream to start reading.
201 *
202 * buffer ::
203 * The address of buffer to store the read data.
204 *
205 * count ::
206 * The number of bytes to read from the stream.
207 *
208 * @Return:
209 * The number of bytes actually read. If `count' is zero (that is,
210 * the function is used for seeking), a non-zero return value
211 * indicates an error.
212 */
213 FT_CALLBACK_DEF( unsigned long )
214 ft_ansi_stream_io( FT_Stream stream,
215 unsigned long offset,
216 unsigned char* buffer,
217 unsigned long count )
218 {
219 FT_FILE* file;
220
221
222 if ( offset > stream->size && !count )
223 return 1;
224
225 file = STREAM_FILE( stream );
226
227 if ( stream->pos != offset )
228 ft_fseek( file, (long)offset, SEEK_SET );
229
230 /* Avoid calling `fread` with `buffer=NULL` and `count=0`, */
231 /* which is undefined behaviour. */
232 if ( !count )
233 return 0;
234
235 return (unsigned long)ft_fread( buffer, 1, count, file );
236 }
237
238
239 /* documentation is in ftstream.h */
240
241 FT_BASE_DEF( FT_Error )
242 FT_Stream_Open( FT_Stream stream,
243 const char* filepathname )
244 {
245 FT_FILE* file;
246
247
248 if ( !stream )
249 return FT_THROW( Invalid_Stream_Handle );
250
251 stream->descriptor.pointer = NULL;
252 stream->pathname.pointer = (char*)filepathname;
253 stream->base = NULL;
254 stream->pos = 0;
255 stream->read = NULL;
256 stream->close = NULL;
257
258 file = ft_fopen( filepathname, "rb" );
259 if ( !file )
260 {
261 FT_ERROR(( "FT_Stream_Open:"
262 " could not open `%s'\n", filepathname ));
263
264 return FT_THROW( Cannot_Open_Resource );
265 }
266
267 ft_fseek( file, 0, SEEK_END );
268 stream->size = (unsigned long)ft_ftell( file );
269 if ( !stream->size )
270 {
271 FT_ERROR(( "FT_Stream_Open:" ));
272 FT_ERROR(( " opened `%s' but zero-sized\n", filepathname ));
273 ft_fclose( file );
274 return FT_THROW( Cannot_Open_Stream );
275 }
276 ft_fseek( file, 0, SEEK_SET );
277
278 stream->descriptor.pointer = file;
279 stream->read = ft_ansi_stream_io;
280 stream->close = ft_ansi_stream_close;
281
282 FT_TRACE1(( "FT_Stream_Open:" ));
283 FT_TRACE1(( " opened `%s' (%ld bytes) successfully\n",
284 filepathname, stream->size ));
285
286 return FT_Err_Ok;
287 }
288
289 #endif /* !FT_CONFIG_OPTION_DISABLE_STREAM_SUPPORT */
290
291 #ifdef FT_DEBUG_MEMORY
292
293 extern FT_Int
294 ft_mem_debug_init( FT_Memory memory );
295
296 extern void
297 ft_mem_debug_done( FT_Memory memory );
298
299 #endif
300
301
302 /* documentation is in ftobjs.h */
303
304 FT_BASE_DEF( FT_Memory )
305 FT_New_Memory( void )
306 {
307 FT_Memory memory;
308
309
310 memory = (FT_Memory)ft_smalloc( sizeof ( *memory ) );
311 if ( memory )
312 {
313 memory->user = NULL;
314 memory->alloc = ft_alloc;
315 memory->realloc = ft_realloc;
316 memory->free = ft_free;
317 #ifdef FT_DEBUG_MEMORY
318 ft_mem_debug_init( memory );
319 #endif
320 }
321
322 return memory;
323 }
324
325
326 /* documentation is in ftobjs.h */
327
328 FT_BASE_DEF( void )
329 FT_Done_Memory( FT_Memory memory )
330 {
331 #ifdef FT_DEBUG_MEMORY
332 ft_mem_debug_done( memory );
333 #endif
334 ft_sfree( memory );
335 }
336
337
338 /* END */