src/image-load.c

   1 /*
   2  * GQview
   3  * (C) 2004 John Ellis
   4  *
   5  * Author: John Ellis
   6  *
   7  * This software is released under the GNU General Public License (GNU GPL).
   8  * Please read the included file COPYING for more information.
   9  * This software comes with no warranty of any kind, use at your own risk!
  10  */
  11
  12
  13 #include "gqview.h"
  14 #include "image-load.h"
  15
  16 #include "ui_fileops.h"
  17
  18 #include <fcntl.h>
  19
  20
  21 /* bytes to read from file per read() */
  22 #define IMAGE_LOADER_BUFFER_SIZE 512
  23
  24 /* the number of bytes to read per idle call (define x IMAGE_LOADER_BUFFER_SIZE) */
  25 #define IMAGE_LOADER_BUFFER_DEFAULT_COUNT 1
  26
  27 static void image_loader_sync_pixbuf(ImageLoader *il)
  28 {
  29         GdkPixbuf *pb;
  30
  31         if (!il->loader) return;
  32
  33         pb = gdk_pixbuf_loader_get_pixbuf(il->loader);
  34
  35         if (pb == il->pixbuf) return;
  36
  37         if (il->pixbuf) gdk_pixbuf_unref(il->pixbuf);
  38         il->pixbuf = pb;
  39         if (il->pixbuf) gdk_pixbuf_ref(il->pixbuf);
  40 }
  41
  42 static void image_loader_area_cb(GdkPixbufLoader *loader,
  43                                  guint x, guint y, guint w, guint h,
  44                                  gpointer data)
  45 {
  46         ImageLoader *il = data;
  47
  48         if (il->func_area_ready)
  49                 {
  50                 if (!il->pixbuf)
  51                         {
  52                         image_loader_sync_pixbuf(il);
  53                         if (!il->pixbuf)
  54                                 {
  55                                 printf("critical: area_ready signal with NULL pixbuf (out of mem?)\n");
  56                                 }
  57                         }
  58                 il->func_area_ready(il, x, y, w, h, il->data_area_ready);
  59                 }
  60 }
  61
  62 static void image_loader_size_cb(GdkPixbufLoader *loader,
  63                                  gint width, gint height, gpointer data)
  64 {
  65         ImageLoader *il = data;
  66         GdkPixbufFormat *format;
  67         gchar **mime_types;
  68         gint scale = FALSE;
  69         gint n;
  70
  71         if (il->requested_width < 1 || il->requested_height < 1) return;
  72
  73         format = gdk_pixbuf_loader_get_format(loader);
  74         if (!format) return;
  75
  76         mime_types = gdk_pixbuf_format_get_mime_types(format);
  77         n = 0;
  78         while (mime_types[n])
  79                 {
  80                 if (strstr(mime_types[n], "jpeg")) scale = TRUE;
  81                 n++;
  82                 }
  83         g_strfreev(mime_types);
  84
  85         if (!scale) return;
  86
  87         if (width > il->requested_width || height > il->requested_height)
  88                 {
  89                 gint nw, nh;
  90
  91                 if (((gdouble)il->requested_width / width) < ((gdouble)il->requested_height / height))
  92                         {
  93                         nw = il->requested_width;
  94                         nh = (gdouble)nw / width * height;
  95                         if (nh < 1) nh = 1;
  96                         }
  97                 else
  98                         {
  99                         nh = il->requested_height;
 100                         nw = (gdouble)nh / height * width;
 101                         if (nw < 1) nw = 1;
 102                         }
 103
 104                 gdk_pixbuf_loader_set_size(loader, nw, nh);
 105                 }
 106 }
 107
 108 static void image_loader_stop(ImageLoader *il)
 109 {
 110         if (!il) return;
 111
 112         if (il->idle_id != -1)
 113                 {
 114                 g_source_remove(il->idle_id);
 115                 il->idle_id = -1;
 116                 }
 117
 118         if (il->loader)
 119                 {
 120                 /* some loaders do not have a pixbuf till close, order is important here */
 121                 gdk_pixbuf_loader_close(il->loader, NULL);
 122                 image_loader_sync_pixbuf(il);
 123                 g_object_unref(G_OBJECT(il->loader));
 124                 il->loader = NULL;
 125                 }
 126
 127         if (il->load_fd != -1)
 128                 {
 129                 close(il->load_fd);
 130                 il->load_fd = -1;
 131                 }
 132
 133         il->done = TRUE;
 134 }
 135
 136 static void image_loader_done(ImageLoader *il)
 137 {
 138         image_loader_stop(il);
 139
 140         if (il->func_done) il->func_done(il, il->data_done);
 141 }
 142
 143 static gint image_loader_done_delay_cb(gpointer data)
 144 {
 145         ImageLoader *il = data;
 146
 147         il->idle_done_id = -1;
 148         image_loader_done(il);
 149         return FALSE;
 150 }
 151
 152 static void image_loader_done_delay(ImageLoader *il)
 153 {
 154         if (il->idle_done_id == -1) il->idle_done_id = g_idle_add_full(il->idle_priority,
 155                                                                        image_loader_done_delay_cb, il, NULL);
 156 }
 157
 158 static void image_loader_error(ImageLoader *il)
 159 {
 160         image_loader_stop(il);
 161
 162         if (debug) printf("pixbuf_loader reported load error for: %s\n", il->path);
 163
 164         if (il->func_error) il->func_error(il, il->data_error);
 165 }
 166
 167 static gint image_loader_idle_cb(gpointer data)
 168 {
 169         ImageLoader *il = data;
 170         guchar buf[IMAGE_LOADER_BUFFER_SIZE];
 171         gint b;
 172         gint c;
 173
 174         if (!il) return FALSE;
 175
 176         if (il->idle_id == -1) return FALSE;
 177
 178         c = il->buffer_size ? il->buffer_size : 1;
 179         while (c > 0)
 180                 {
 181                 b = read(il->load_fd, &buf, sizeof(buf));
 182
 183                 if (b == 0)
 184                         {
 185                         image_loader_done(il);
 186                         return FALSE;
 187                         }
 188
 189                 if (b < 0 || (b > 0 && !gdk_pixbuf_loader_write(il->loader, buf, b, NULL)))
 190                         {
 191                         image_loader_error(il);
 192                         return FALSE;
 193                         }
 194
 195                 il->bytes_read += b;
 196
 197                 c--;
 198                 }
 199
 200         if (il->func_percent && il->bytes_total > 0)
 201                 {
 202                 il->func_percent(il, (gdouble)il->bytes_read / il->bytes_total, il->data_percent);
 203                 }
 204
 205         return TRUE;
 206 }
 207
 208 static gint image_loader_begin(ImageLoader *il)
 209 {
 210         guchar buf[IMAGE_LOADER_BUFFER_SIZE];
 211         int b;
 212
 213         if (!il->loader || il->pixbuf) return FALSE;
 214
 215         b = read(il->load_fd, &buf, sizeof(buf));
 216
 217         if (b < 1)
 218                 {
 219                 image_loader_stop(il);
 220                 return FALSE;
 221                 }
 222
 223         if (gdk_pixbuf_loader_write(il->loader, buf, b, NULL))
 224                 {
 225                 il->bytes_read += b;
 226
 227                 if (b < sizeof(buf))
 228                         {
 229                         /* end of file already */
 230
 231                         image_loader_stop(il);
 232
 233                         if (!il->pixbuf) return FALSE;
 234
 235                         image_loader_done_delay(il);
 236                         return TRUE;
 237                         }
 238                 else
 239                         {
 240                         /* larger file */
 241
 242                         /* read until size is known */
 243                         while(il->loader && !gdk_pixbuf_loader_get_pixbuf(il->loader) && b > 0)
 244                                 {
 245                                 b = read(il->load_fd, &buf, sizeof(buf));
 246                                 if (b < 0 || (b > 0 && !gdk_pixbuf_loader_write(il->loader, buf, b, NULL)))
 247                                         {
 248                                         image_loader_stop(il);
 249                                         return FALSE;
 250                                         }
 251                                 il->bytes_read += b;
 252                                 }
 253                         if (!il->pixbuf) image_loader_sync_pixbuf(il);
 254
 255                         if (il->bytes_read == il->bytes_total || b < sizeof(buf))
 256                                 {
 257                                 /* done, handle (broken) loaders that do not have pixbuf till close */
 258                                 image_loader_stop(il);
 259
 260                                 if (!il->pixbuf) return FALSE;
 261
 262                                 image_loader_done_delay(il);
 263                                 return TRUE;
 264                                 }
 265
 266                         if (!il->pixbuf)
 267                                 {
 268                                 image_loader_stop(il);
 269                                 return FALSE;
 270                                 }
 271
 272                         /* finally, progressive loading :) */
 273                         il->idle_id = g_idle_add_full(il->idle_priority, image_loader_idle_cb, il, NULL);
 274                         return TRUE;
 275                         }
 276                 }
 277         else
 278                 {
 279                 image_loader_stop(il);
 280                 return FALSE;
 281                 }
 282
 283         return TRUE;
 284 }
 285
 286 static gint image_loader_setup(ImageLoader *il)
 287 {
 288         struct stat st;
 289         gchar *pathl;
 290
 291         if (!il || il->load_fd != -1 || il->loader) return FALSE;
 292
 293         pathl = path_from_utf8(il->path);
 294         il->load_fd = open(pathl, O_RDONLY | O_NONBLOCK);
 295         g_free(pathl);
 296         if (il->load_fd == -1) return FALSE;
 297
 298         if (fstat(il->load_fd, &st) == 0)
 299                 {
 300                 il->bytes_total = st.st_size;
 301                 }
 302
 303         il->loader = gdk_pixbuf_loader_new();
 304         g_signal_connect(G_OBJECT(il->loader), "area_updated",
 305                          G_CALLBACK(image_loader_area_cb), il);
 306         g_signal_connect(G_OBJECT(il->loader), "size_prepared",
 307                          G_CALLBACK(image_loader_size_cb), il);
 308
 309         return image_loader_begin(il);
 310 }
 311
 312 ImageLoader *image_loader_new(const gchar *path)
 313 {
 314         ImageLoader *il;
 315
 316         if (!path) return NULL;
 317
 318         il = g_new0(ImageLoader, 1);
 319         if (path) il->path = g_strdup(path);
 320         il->pixbuf = NULL;
 321         il->idle_id = -1;
 322         il->idle_priority = G_PRIORITY_DEFAULT_IDLE;
 323         il->done = FALSE;
 324         il->loader = NULL;
 325         il->load_fd = -1;
 326
 327         il->bytes_read = 0;
 328         il->bytes_total = 0;
 329
 330         il->idle_done_id = -1;
 331
 332         il->buffer_size = IMAGE_LOADER_BUFFER_DEFAULT_COUNT;
 333
 334         il->requested_width = 0;
 335         il->requested_height = 0;
 336
 337         return il;
 338 }
 339
 340 void image_loader_free(ImageLoader *il)
 341 {
 342         if (!il) return;
 343
 344         image_loader_stop(il);
 345         if (il->idle_done_id != -1) g_source_remove(il->idle_done_id);
 346         if (il->pixbuf) gdk_pixbuf_unref(il->pixbuf);
 347         g_free(il->path);
 348         g_free(il);
 349 }
 350
 351 /* don't forget to gdk_pixbuf_ref() it if you want to use it after image_loader_free() */
 352 GdkPixbuf *image_loader_get_pixbuf(ImageLoader *il)
 353 {
 354         if (!il) return NULL;
 355
 356         return il->pixbuf;
 357 }
 358
 359 gchar *image_loader_get_format(ImageLoader *il)
 360 {
 361         GdkPixbufFormat *format;
 362         gchar **mimev;
 363         gchar *mime;
 364
 365         if (!il || !il->loader) return NULL;
 366
 367         format = gdk_pixbuf_loader_get_format(il->loader);
 368         if (!format) return NULL;
 369
 370         mimev = gdk_pixbuf_format_get_mime_types(format);
 371         if (!mimev) return NULL;
 372
 373         /* return first member of mimev, as GdkPixbufLoader has no way to tell us which exact one ? */
 374         mime = g_strdup(mimev[0]);
 375         g_strfreev(mimev);
 376
 377         return mime;
 378 }
 379
 380 void image_loader_set_area_ready_func(ImageLoader *il,
 381                                       void (*func_area_ready)(ImageLoader *, guint, guint, guint, guint, gpointer),
 382                                       gpointer data_area_ready)
 383 {
 384         if (!il) return;
 385
 386         il->func_area_ready = func_area_ready;
 387         il->data_area_ready = data_area_ready;
 388 }
 389
 390 void image_loader_set_error_func(ImageLoader *il,
 391                                  void (*func_error)(ImageLoader *, gpointer),
 392                                  gpointer data_error)
 393 {
 394         if (!il) return;
 395
 396         il->func_error = func_error;
 397         il->data_error = data_error;
 398 }
 399
 400 void image_loader_set_percent_func(ImageLoader *il,
 401                                    void (*func_percent)(ImageLoader *, gdouble, gpointer),
 402                                    gpointer data_percent)
 403 {
 404         if (!il) return;
 405
 406         il->func_percent = func_percent;
 407         il->data_percent = data_percent;
 408 }
 409
 410 void image_loader_set_requested_size(ImageLoader *il, gint width, gint height)
 411 {
 412         if (!il) return;
 413
 414         il->requested_width = width;
 415         il->requested_height = height;
 416 }
 417
 418 void image_loader_set_buffer_size(ImageLoader *il, guint size)
 419 {
 420         if (!il) return;
 421
 422         il->buffer_size = size ? size : 1;
 423 }
 424
 425 void image_loader_set_priority(ImageLoader *il, gint priority)
 426 {
 427         if (!il) return;
 428
 429         il->idle_priority = priority;
 430 }
 431
 432 gint image_loader_start(ImageLoader *il, void (*func_done)(ImageLoader *, gpointer), gpointer data_done)
 433 {
 434         if (!il) return FALSE;
 435
 436         if (!il->path) return FALSE;
 437
 438         il->func_done = func_done;
 439         il->data_done = data_done;
 440
 441         return image_loader_setup(il);
 442 }
 443
 444 gdouble image_loader_get_percent(ImageLoader *il)
 445 {
 446         if (!il || il->bytes_total == 0) return 0.0;
 447
 448         return (gdouble)il->bytes_read / il->bytes_total;
 449 }
 450
 451 gint image_loader_get_is_done(ImageLoader *il)
 452 {
 453         if (!il) return FALSE;
 454
 455         return il->done;
 456 }
 457
 458 gint image_load_dimensions(const gchar *path, gint *width, gint *height)
 459 {
 460         ImageLoader *il;
 461         gint success;
 462
 463         il = image_loader_new(path);
 464
 465         success = image_loader_start(il, NULL, NULL);
 466
 467         if (success && il->pixbuf)
 468                 {
 469                 if (width) *width = gdk_pixbuf_get_width(il->pixbuf);
 470                 if (height) *height = gdk_pixbuf_get_height(il->pixbuf);;
 471                 }
 472         else
 473                 {
 474                 if (width) *width = -1;
 475                 if (height) *height = -1;
 476                 }
 477
 478         image_loader_free(il);
 479
 480         return success;
 481 }
 482