1 /* -*- Mode: C; tab-width: 3; indent-tabs-mode: nil; c-basic-offset: 3 -*- */
2
3 /*
4 * GImageView
5 * Copyright (C) 2001 Takuro Ashie
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 *
21 * $Id: gimv_io_mem.c,v 1.2 2004/09/21 08:44:32 makeinu Exp $
22 */
23
24 #include "gimv_io_mem.h"
25
26 #include <string.h>
27
28
29 static GimvIOStatus gimv_io_mem_read (GimvIO *gio,
30 gchar *buf,
31 guint count,
32 guint *bytes_read);
33 static GimvIOStatus gimv_io_mem_write (GimvIO *gio,
34 const gchar *buf,
35 guint count,
36 guint *bytes_written);
37 static GimvIOStatus gimv_io_mem_seek (GimvIO *gio,
38 glong offset,
39 gint whence);
40 static GimvIOStatus gimv_io_mem_tell (GimvIO *gio,
41 glong *offset);
42 static void gimv_io_mem_close (GimvIO *gio);
43
44
45 GimvIOFuncs gimv_io_mem_funcs =
46 {
47 gimv_io_mem_read,
48 gimv_io_mem_write,
49 gimv_io_mem_seek,
50 gimv_io_mem_tell,
51 gimv_io_mem_close,
52 };
53
54
55 void
gimv_io_mem_init(GimvIOMem * memio,const gchar * url,const gchar * mode,GimvIOMemMode memio_mode)56 gimv_io_mem_init (GimvIOMem *memio,
57 const gchar *url,
58 const gchar *mode,
59 GimvIOMemMode memio_mode)
60 {
61 GimvIO *gio;
62 gint i;
63
64 g_return_if_fail (memio);
65
66 gio = (GimvIO *) memio;
67
68 gimv_io_init (gio, url);
69 gio->funcs = &gimv_io_mem_funcs;
70
71 memio->memio_mode = memio_mode;
72 switch (memio->memio_mode) {
73 case GimvIOMemModeWrap:
74 memio->free_buf = FALSE;
75 memio->buf = NULL;
76 break;
77 case GimvIOMemModeStack:
78 default:
79 memio->buf = g_new0 (gchar *, GIMV_IO_MEM_BLOCKS_STEP);
80 for (i = 0; i < GIMV_IO_MEM_BLOCKS_STEP; i++)
81 ((gchar **)memio->buf)[i] = NULL;
82 break;
83 }
84 memio->bufsize = 0;
85 memio->pos = 0;
86 }
87
88
89 GimvIO *
gimv_io_mem_new(const gchar * url,const gchar * mode,GimvIOMemMode memio_mode)90 gimv_io_mem_new (const gchar *url,
91 const gchar *mode,
92 GimvIOMemMode memio_mode)
93 {
94 GimvIOMem *memio;
95
96 memio = g_new0 (GimvIOMem, 1);
97
98 gimv_io_mem_init (memio, url, mode, memio_mode);
99
100 return (GimvIO *) memio;
101 }
102
103
104 void
gimv_io_mem_stack(GimvIOMem * memio,const gchar * buf,guint bufsize)105 gimv_io_mem_stack (GimvIOMem *memio,
106 const gchar *buf, guint bufsize)
107 {
108 gint i, src_blocks, dest_blocks, src_steps, dest_steps;
109 guint bytes, src_size, dest_size, remain, offset;
110 const gchar *src;
111
112 g_return_if_fail (memio);
113 g_return_if_fail (memio->memio_mode == GimvIOMemModeStack);
114 g_return_if_fail (buf);
115
116 src_size = memio->bufsize;
117 dest_size = memio->bufsize + bufsize;
118
119 src_blocks = src_size / GIMV_IO_MEM_BLOCK_SIZE + 1;
120 dest_blocks = dest_size / GIMV_IO_MEM_BLOCK_SIZE + 1;
121
122 src_steps = src_blocks / GIMV_IO_MEM_BLOCKS_STEP + 1;
123 dest_steps = dest_blocks / GIMV_IO_MEM_BLOCKS_STEP + 1;
124
125 if (dest_steps > src_steps) {
126 memio->buf
127 = g_renew (gchar *, memio->buf,
128 GIMV_IO_MEM_BLOCKS_STEP * dest_steps);
129 for (i = GIMV_IO_MEM_BLOCKS_STEP * src_steps; i < dest_blocks; i++) {
130 ((gchar **) memio->buf)[i] = NULL;
131 }
132 }
133
134 remain = bufsize;
135
136 bytes = MIN (src_blocks * GIMV_IO_MEM_BLOCK_SIZE - src_size, remain);
137 src = buf;
138 if (!((gchar **) memio->buf)[src_blocks - 1])
139 ((gchar **) memio->buf)[src_blocks - 1]
140 = g_new0 (gchar, GIMV_IO_MEM_BLOCK_SIZE);
141 offset = src_size - (src_blocks - 1) * GIMV_IO_MEM_BLOCK_SIZE;
142 memcpy (((gchar **) memio->buf)[src_blocks - 1] + offset, src, bytes);
143 remain -= bytes;
144
145 for (i = src_blocks; i < dest_blocks; i++) {
146 bytes = MIN (GIMV_IO_MEM_BLOCK_SIZE, remain);
147 src = buf + (bufsize - remain);
148 if (!((gchar **) memio->buf)[i])
149 ((gchar **) memio->buf)[i] = g_new0 (gchar, GIMV_IO_MEM_BLOCK_SIZE);
150 memcpy (((gchar **) memio->buf)[i], src, bytes);
151 remain -= bytes;
152 }
153
154 memio->bufsize = dest_size;
155 }
156
157
158 void
gimv_io_mem_wrap(GimvIOMem * memio,const gchar * buf,guint bufsize,gboolean free)159 gimv_io_mem_wrap (GimvIOMem *memio,
160 const gchar *buf, guint bufsize,
161 gboolean free)
162 {
163 g_return_if_fail (memio);
164 g_return_if_fail (memio->memio_mode == GimvIOMemModeWrap);
165 g_return_if_fail (buf);
166
167 if (memio->buf && memio->free_buf)
168 g_free (memio->buf);
169
170 memio->free_buf = free;
171 memio->buf = (gpointer) buf;
172 memio->bufsize = bufsize;
173 }
174
175
176 static GimvIOStatus
io_mem_read_stack_mode(GimvIOMem * memio,gchar * buf,guint count,guint * bytes_read)177 io_mem_read_stack_mode (GimvIOMem *memio,
178 gchar *buf,
179 guint count,
180 guint *bytes_read)
181 {
182 gchar *dest;
183 guint idx, offset;
184 guint bytes, remain;
185
186 g_return_val_if_fail (memio->pos <= memio->bufsize, GIMV_IO_STATUS_ERROR);
187 g_return_val_if_fail (bytes_read, GIMV_IO_STATUS_ERROR);
188
189 remain = count;
190 *bytes_read = 0;
191
192 idx = memio->pos / GIMV_IO_MEM_BLOCK_SIZE;
193 offset = memio->pos % GIMV_IO_MEM_BLOCK_SIZE;
194 bytes = MIN (remain, GIMV_IO_MEM_BLOCK_SIZE - offset);
195 dest = buf;
196
197 memcpy (dest, ((gchar **) memio->buf)[idx] + offset, bytes);
198
199 *bytes_read += bytes;
200 memio->pos += bytes;
201 remain -= bytes;
202 dest += bytes;
203
204 while (remain > 0) {
205 idx++;
206
207 bytes = MIN (remain, GIMV_IO_MEM_BLOCK_SIZE);
208
209 memcpy (dest, ((gchar **) memio->buf)[idx], bytes);
210
211 *bytes_read += bytes;
212 memio->pos += bytes;
213 remain -= bytes;
214 dest += bytes;
215 }
216
217 return GIMV_IO_STATUS_NORMAL;
218 }
219
220
221 static GimvIOStatus
gimv_io_mem_read(GimvIO * gio,gchar * buf,guint count,guint * bytes_read)222 gimv_io_mem_read (GimvIO *gio,
223 gchar *buf,
224 guint count,
225 guint *bytes_read)
226 {
227 GimvIOMem *memio = (GimvIOMem *) gio;
228
229 *bytes_read = 0;
230
231 if (memio->pos == memio->bufsize) {
232 return GIMV_IO_STATUS_NORMAL;
233 } else if (memio->pos > memio->bufsize) {
234 memio->pos = memio->bufsize;
235 return GIMV_IO_STATUS_ERROR;
236 }
237
238 switch (memio->memio_mode) {
239 case GimvIOMemModeWrap:
240 *bytes_read = MIN (count, ((guint) memio->bufsize - memio->pos));
241 memcpy (buf, ((char *) memio->buf) + memio->pos, *bytes_read);
242 memio->pos += *bytes_read;
243 break;
244 case GimvIOMemModeStack:
245 default:
246 io_mem_read_stack_mode (memio, buf, count, bytes_read);
247 break;
248 }
249
250 return GIMV_IO_STATUS_NORMAL;
251 }
252
253
254 static GimvIOStatus
gimv_io_mem_write(GimvIO * gio,const gchar * buf,guint count,guint * bytes_written)255 gimv_io_mem_write (GimvIO *gio,
256 const gchar *buf,
257 guint count,
258 guint *bytes_written)
259
260 {
261 /* GimvIOMem *memio = (GimvIOMem *) gio; */
262
263 /* FIXME */
264
265 return GIMV_IO_STATUS_ERROR;
266 }
267
268
269 static GimvIOStatus
gimv_io_mem_seek(GimvIO * gio,glong offset,gint whence)270 gimv_io_mem_seek (GimvIO *gio,
271 glong offset,
272 gint whence)
273 {
274 GimvIOMem *memio = (GimvIOMem *) gio;
275 glong pos;
276
277 switch (whence) {
278 case SEEK_CUR:
279 pos = memio->pos + offset;
280 break;
281 case SEEK_SET:
282 pos = offset;
283 break;
284 case SEEK_END:
285 pos = memio->bufsize + offset;
286 break;
287 default:
288 return GIMV_IO_STATUS_ERROR;
289 break;
290 }
291
292 if (pos > memio->bufsize) {
293 memio->pos = memio->bufsize;
294 return GIMV_IO_STATUS_ERROR;
295 } else if (pos < 0) {
296 memio->pos = 0;
297 return GIMV_IO_STATUS_ERROR;
298 }
299
300 memio->pos = pos;
301
302 return GIMV_IO_STATUS_NORMAL;
303 }
304
305
306 static GimvIOStatus
gimv_io_mem_tell(GimvIO * gio,glong * offset)307 gimv_io_mem_tell (GimvIO *gio,
308 glong *offset)
309 {
310 GimvIOMem *memio = (GimvIOMem *) gio;
311
312 g_return_val_if_fail (offset, GIMV_IO_STATUS_ERROR);
313
314 *offset = memio->pos;
315
316 return GIMV_IO_STATUS_NORMAL;
317 }
318
319
320 static void
gimv_io_mem_close(GimvIO * gio)321 gimv_io_mem_close (GimvIO *gio)
322 {
323 GimvIOMem *memio = (GimvIOMem *) gio;
324 gint block_num, i;
325
326 switch (memio->memio_mode) {
327 case GimvIOMemModeWrap:
328 if (memio->free_buf)
329 g_free (memio->buf);
330 memio->buf = NULL;
331 break;
332 case GimvIOMemModeStack:
333 default:
334 block_num = memio->bufsize / GIMV_IO_MEM_BLOCK_SIZE + 1;
335 for (i = 0; i < block_num; i++) {
336 g_free (((gchar **)memio->buf)[i]);
337 }
338 g_free (memio->buf);
339 break;
340 }
341 }
342