backend/comics/comics-document.c

   1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8; c-indent-level: 8 -*- */
   2 /*
   3  * Copyright (C) 2009-2010 Juanjo Marín <juanj.marin@juntadeandalucia.es>
   4  * Copyright (C) 2005, Teemu Tervo <teemu.tervo@gmx.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2, or (at your option)
   9  * any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  */
  20
  21 #include <config.h>
  22
  23 #include <unistd.h>
  24 #include <string.h>
  25 #include <stdlib.h>
  26 #include <errno.h>
  27
  28 #include <glib.h>
  29 #include <glib/gi18n-lib.h>
  30 #include <glib/gstdio.h>
  31 #include <gio/gio.h>
  32
  33 #ifdef G_OS_WIN32
  34 # define WIFEXITED(x) ((x) != 3)
  35 # define WEXITSTATUS(x) (x)
  36 #else
  37 # include <sys/wait.h>
  38 #endif
  39
  40 #include "comics-document.h"
  41 #include "ev-document-misc.h"
  42 #include "ev-file-helpers.h"
  43
  44 #ifdef G_OS_WIN32
  45 /* On windows g_spawn_command_line_sync reads stdout in O_BINARY mode, not in O_TEXT mode.
  46  * As a consequence, newlines are in a platform dependent representation (\r\n). This
  47  * might be considered a bug in glib.
  48  */
  49 #define EV_EOL "\r\n"
  50 #else
  51 #define EV_EOL "\n"
  52 #endif
  53
  54 typedef enum
  55 {
  56         RARLABS,
  57         GNAUNRAR,
  58         UNZIP,
  59         P7ZIP,
  60         TAR
  61 } ComicBookDecompressType;
  62
  63 typedef struct _ComicsDocumentClass ComicsDocumentClass;
  64
  65 struct _ComicsDocumentClass
  66 {
  67         EvDocumentClass parent_class;
  68 };
  69
  70 struct _ComicsDocument
  71 {
  72         EvDocument parent_instance;
  73
  74         gchar    *archive, *dir;
  75         GPtrArray *page_names;
  76         gchar    *selected_command, *alternative_command;
  77         gchar    *extract_command, *list_command, *decompress_tmp;
  78         gboolean regex_arg;
  79         gint     offset;
  80         ComicBookDecompressType command_usage;
  81 };
  82
  83 #define OFFSET_7Z 53
  84 #define OFFSET_ZIP 2
  85 #define NO_OFFSET 0
  86
  87 /* For perfomance reasons of 7z* we've choosen to decompress on the temporary
  88  * directory instead of decompressing on the stdout */
  89
  90 /**
  91  * @extract: command line arguments to pass to extract a file from the archive
  92  *   to stdout.
  93  * @list: command line arguments to list the archive contents
  94  * @decompress_tmp: command line arguments to pass to extract the archive
  95  *   into a directory.
  96  * @regex_arg: whether the command can accept regex expressions
  97  * @offset: the position offset of the filename on each line in the output of
  98  *   running the @list command
  99  */
 100 typedef struct {
 101         char *extract;
 102         char *list;
 103         char *decompress_tmp;
 104         gboolean regex_arg;
 105         gint offset;
 106 } ComicBookDecompressCommand;
 107
 108 static const ComicBookDecompressCommand command_usage_def[] = {
 109         /* RARLABS unrar */
 110         {"%s p -c- -ierr --", "%s vb -c- -- %s", NULL             , FALSE, NO_OFFSET},
 111
 112         /* GNA! unrar */
 113         {NULL               , "%s t %s"        , "%s -xf %s %s"   , FALSE, NO_OFFSET},
 114
 115         /* unzip */
 116         {"%s -p -C --"      , "%s %s"          , NULL             , TRUE , OFFSET_ZIP},
 117
 118         /* 7zip */
 119         {NULL               , "%s l -- %s"     , "%s x -y %s -o%s", FALSE, OFFSET_7Z},
 120
 121         /* tar */
 122         {"%s -xOf"          , "%s -tf %s"      , NULL             , FALSE, NO_OFFSET}
 123 };
 124
 125 static GSList*    get_supported_image_extensions (void);
 126 static void       get_page_size_area_prepared_cb (GdkPixbufLoader *loader,
 127                                                   gpointer data);
 128 static void       render_pixbuf_size_prepared_cb (GdkPixbufLoader *loader,
 129                                                   gint width,
 130                                                   gint height,
 131                                                   gpointer data);
 132 static char**     extract_argv                   (EvDocument *document,
 133                                                   gint page);
 134
 135
 136 EV_BACKEND_REGISTER (ComicsDocument, comics_document)
 137
 138 /**
 139  * comics_regex_quote:
 140  * @unquoted_string: a literal string
 141  *
 142  * Quotes a string so unzip will not interpret the regex expressions of
 143  * @unquoted_string. Basically, this functions uses [] to disable regex
 144  * expressions. The return value must be freed with * g_free()
 145  *
 146  * Return value: quoted and disabled-regex string
 147  **/
 148 static gchar *
 149 comics_regex_quote (const gchar *unquoted_string)
 150 {
 151         const gchar *p;
 152         GString *dest;
 153
 154         dest = g_string_new ("'");
 155
 156         p = unquoted_string;
 157
 158         while (*p) {
 159                 switch (*p) {
 160                         /* * matches a sequence of 0 or more characters */
 161                         case ('*'):
 162                         /* ? matches exactly 1 charactere */
 163                         case ('?'):
 164                         /* [...]  matches any single character found inside
 165                          * the brackets. Disabling the first bracket is enough.
 166                          */
 167                         case ('['):
 168                                 g_string_append (dest, "[");
 169                                 g_string_append_c (dest, *p);
 170                                 g_string_append (dest, "]");
 171                                 break;
 172                         /* Because \ escapes regex expressions that we are
 173                          * disabling for unzip, we need to disable \ too */
 174                         case ('\\'):
 175                                 g_string_append (dest, "[\\\\]");
 176                                 break;
 177                         /* Escape single quote inside the string */
 178                         case ('\''):
 179                                 g_string_append (dest, "'\\''");
 180                                 break;
 181                         default:
 182                                 g_string_append_c (dest, *p);
 183                                 break;
 184                 }
 185                 ++p;
 186         }
 187         g_string_append_c (dest, '\'');
 188         return g_string_free (dest, FALSE);
 189 }
 190
 191
 192 /* This function manages the command for decompressing a comic book */
 193 static gboolean
 194 comics_decompress_temp_dir (const gchar *command_decompress_tmp,
 195                             const gchar *command,
 196                             GError      **error)
 197 {
 198         gboolean success;
 199         gchar *std_out, *basename;
 200         GError *err = NULL;
 201         gint retval;
 202
 203         success = g_spawn_command_line_sync (command_decompress_tmp, &std_out,
 204                                              NULL, &retval, &err);
 205         basename = g_path_get_basename (command);
 206         if (!success) {
 207                 g_set_error (error,
 208                              EV_DOCUMENT_ERROR,
 209                              EV_DOCUMENT_ERROR_INVALID,
 210                              _("Error launching the command “%s” in order to "
 211                              "decompress the comic book: %s"),
 212                              basename,
 213                              err->message);
 214                 g_error_free (err);
 215         } else if (WIFEXITED (retval)) {
 216                 if (WEXITSTATUS (retval) == EXIT_SUCCESS) {
 217                         g_free (std_out);
 218                         g_free (basename);
 219                         return TRUE;
 220                 } else {
 221                         g_set_error (error,
 222                                      EV_DOCUMENT_ERROR,
 223                                      EV_DOCUMENT_ERROR_INVALID,
 224                                      _("The command “%s” failed at "
 225                                      "decompressing the comic book."),
 226                                      basename);
 227                         g_free (std_out);
 228                 }
 229         } else {
 230                 g_set_error (error,
 231                              EV_DOCUMENT_ERROR,
 232                              EV_DOCUMENT_ERROR_INVALID,
 233                              _("The command “%s” did not end normally."),
 234                              basename);
 235                 g_free (std_out);
 236         }
 237         g_free (basename);
 238         return FALSE;
 239 }
 240
 241 /* This function shows how to use the choosen command for decompressing a
 242  * comic book file. It modifies fields of the ComicsDocument struct with
 243  * this information */
 244 static gboolean
 245 comics_generate_command_lines (ComicsDocument *comics_document,
 246                                GError         **error)
 247 {
 248         gchar *quoted_file, *quoted_file_aux;
 249         gchar *quoted_command;
 250         ComicBookDecompressType type;
 251
 252         type = comics_document->command_usage;
 253         comics_document->regex_arg = command_usage_def[type].regex_arg;
 254         quoted_command = g_shell_quote (comics_document->selected_command);
 255         if (comics_document->regex_arg) {
 256                 quoted_file = comics_regex_quote (comics_document->archive);
 257                 quoted_file_aux = g_shell_quote (comics_document->archive);
 258                 comics_document->list_command =
 259                            g_strdup_printf (command_usage_def[type].list,
 260                                             comics_document->alternative_command,
 261                                             quoted_file_aux);
 262                 g_free (quoted_file_aux);
 263         } else {
 264                 quoted_file = g_shell_quote (comics_document->archive);
 265                 comics_document->list_command =
 266                                 g_strdup_printf (command_usage_def[type].list,
 267                                                  quoted_command, quoted_file);
 268         }
 269         comics_document->extract_command =
 270                             g_strdup_printf (command_usage_def[type].extract,
 271                                              quoted_command);
 272         comics_document->offset = command_usage_def[type].offset;
 273         if (command_usage_def[type].decompress_tmp) {
 274                 comics_document->dir = ev_mkdtemp ("evince-comics-XXXXXX", error);
 275                 if (comics_document->dir == NULL)
 276                         return FALSE;
 277
 278                 /* unrar-free can't create directories, but ev_mkdtemp already created the dir */
 279
 280                 comics_document->decompress_tmp =
 281                         g_strdup_printf (command_usage_def[type].decompress_tmp,
 282                                          quoted_command, quoted_file,
 283                                          comics_document->dir);
 284                 g_free (quoted_file);
 285                 g_free (quoted_command);
 286
 287                 if (!comics_decompress_temp_dir (comics_document->decompress_tmp,
 288                     comics_document->selected_command, error))
 289                         return FALSE;
 290                 else
 291                         return TRUE;
 292         } else {
 293                 g_free (quoted_file);
 294                 g_free (quoted_command);
 295                 return TRUE;
 296         }
 297
 298 }
 299
 300 /* This function chooses an external command for decompressing a comic
 301  * book based on its mime tipe. */
 302 static gboolean
 303 comics_check_decompress_command (gchar          *mime_type,
 304                                  ComicsDocument *comics_document,
 305                                  GError         **error)
 306 {
 307         gboolean success;
 308         gchar *std_out, *std_err;
 309         gint retval;
 310         GError *err = NULL;
 311
 312         /* FIXME, use proper cbr/cbz mime types once they're
 313          * included in shared-mime-info */
 314
 315         if (!strcmp (mime_type, "application/x-cbr") ||
 316             !strcmp (mime_type, "application/x-rar")) {
 317                 /* The RARLAB provides a no-charge proprietary (freeware)
 318                 * decompress-only client for Linux called unrar. Another
 319                 * option is a GPLv2-licensed command-line tool developed by
 320                 * the Gna! project. Confusingly enough, the free software RAR
 321                 * decoder is also named unrar. For this reason we need to add
 322                 * some lines for disambiguation. Sorry for the added the
 323                 * complexity but it's life :)
 324                 * Finally, some distributions, like Debian, rename this free
 325                 * option as unrar-free.
 326                 * */
 327                 comics_document->selected_command =
 328                                         g_find_program_in_path ("unrar");
 329                 if (comics_document->selected_command) {
 330                         /* We only use std_err to avoid printing useless error
 331                          * messages on the terminal */
 332                         success =
 333                                 g_spawn_command_line_sync (
 334                                               comics_document->selected_command,
 335                                                            &std_out, &std_err,
 336                                                            &retval, &err);
 337                         if (!success) {
 338                                 g_propagate_error (error, err);
 339                                 g_error_free (err);
 340                                 return FALSE;
 341                         /* I don't check retval status because RARLAB unrar
 342                          * doesn't have a way to return 0 without involving an
 343                          * operation with a file*/
 344                         } else if (WIFEXITED (retval)) {
 345                                 if (g_strrstr (std_out,"freeware") != NULL)
 346                                         /* The RARLAB freeware client */
 347                                         comics_document->command_usage = RARLABS;
 348                                 else
 349                                         /* The Gna! free software client */
 350                                         comics_document->command_usage = GNAUNRAR;
 351
 352                                 g_free (std_out);
 353                                 g_free (std_err);
 354                                 return TRUE;
 355                         }
 356                 }
 357                 /* The Gna! free software client with Debian naming convention */
 358                 comics_document->selected_command =
 359                                 g_find_program_in_path ("unrar-free");
 360                 if (comics_document->selected_command) {
 361                         comics_document->command_usage = GNAUNRAR;
 362                         return TRUE;
 363                 }
 364
 365         } else if (!strcmp (mime_type, "application/x-cbz") ||
 366                    !strcmp (mime_type, "application/zip")) {
 367                 /* InfoZIP's unzip program */
 368                 comics_document->selected_command =
 369                                 g_find_program_in_path ("unzip");
 370                 comics_document->alternative_command =
 371                                 g_find_program_in_path ("zipnote");
 372                 if (comics_document->selected_command &&
 373                     comics_document->alternative_command) {
 374                         comics_document->command_usage = UNZIP;
 375                         return TRUE;
 376                 }
 377
 378         } else if (!strcmp (mime_type, "application/x-cb7") ||
 379                    !strcmp (mime_type, "application/x-7z-compressed")) {
 380                 /* 7zr, 7za and 7z are the commands from the p7zip project able
 381                  * to decompress .7z files */
 382                         comics_document->selected_command =
 383                                 g_find_program_in_path ("7zr");
 384                         if (comics_document->selected_command) {
 385                                 comics_document->command_usage = P7ZIP;
 386                                 return TRUE;
 387                         }
 388                         comics_document->selected_command =
 389                                 g_find_program_in_path ("7za");
 390                         if (comics_document->selected_command) {
 391                                 comics_document->command_usage = P7ZIP;
 392                                 return TRUE;
 393                         }
 394                         comics_document->selected_command =
 395                                 g_find_program_in_path ("7z");
 396                         if (comics_document->selected_command) {
 397                                 comics_document->command_usage = P7ZIP;
 398                                 return TRUE;
 399                         }
 400         } else if (!strcmp (mime_type, "application/x-cbt") ||
 401                    !strcmp (mime_type, "application/x-tar")) {
 402                 /* tar utility (Tape ARchive) */
 403                 comics_document->selected_command =
 404                                 g_find_program_in_path ("tar");
 405                 if (comics_document->selected_command) {
 406                         comics_document->command_usage = TAR;
 407                         return TRUE;
 408                 }
 409         } else {
 410                 g_set_error (error,
 411                              EV_DOCUMENT_ERROR,
 412                              EV_DOCUMENT_ERROR_INVALID,
 413                              _("Not a comic book MIME type: %s"),
 414                              mime_type);
 415                              return FALSE;
 416         }
 417         g_set_error_literal (error,
 418                              EV_DOCUMENT_ERROR,
 419                              EV_DOCUMENT_ERROR_INVALID,
 420                              _("Can't find an appropriate command to "
 421                              "decompress this type of comic book"));
 422         return FALSE;
 423 }
 424
 425 static int
 426 sort_page_names (gconstpointer a,
 427                  gconstpointer b)
 428 {
 429   return strcmp (* (const char **) a, * (const char **) b);
 430 }
 431
 432 static gboolean
 433 comics_document_load (EvDocument *document,
 434                       const char *uri,
 435                       GError    **error)
 436 {
 437         ComicsDocument *comics_document = COMICS_DOCUMENT (document);
 438         GSList *supported_extensions;
 439         gchar *std_out;
 440         gchar *mime_type;
 441         gchar **cb_files, *cb_file;
 442         gboolean success;
 443         int i, retval;
 444         GError *err = NULL;
 445
 446         comics_document->archive = g_filename_from_uri (uri, NULL, error);
 447         if (!comics_document->archive)
 448                 return FALSE;
 449
 450         mime_type = ev_file_get_mime_type (uri, FALSE, &err);
 451         if (!mime_type) {
 452                 if (err) {
 453                         g_propagate_error (error, err);
 454                 } else {
 455                         g_set_error_literal (error,
 456                                              EV_DOCUMENT_ERROR,
 457                                              EV_DOCUMENT_ERROR_INVALID,
 458                                              _("Unknown MIME Type"));
 459                 }
 460
 461                 return FALSE;
 462         }
 463
 464         if (!comics_check_decompress_command (mime_type, comics_document,
 465         error)) {
 466                 g_free (mime_type);
 467                 return FALSE;
 468         } else if (!comics_generate_command_lines (comics_document, error)) {
 469                    g_free (mime_type);
 470                 return FALSE;
 471         }
 472
 473         g_free (mime_type);
 474
 475         /* Get list of files in archive */
 476         success = g_spawn_command_line_sync (comics_document->list_command,
 477                                              &std_out, NULL, &retval, error);
 478
 479         if (!success) {
 480                 return FALSE;
 481         } else if (!WIFEXITED(retval) || WEXITSTATUS(retval) != EXIT_SUCCESS) {
 482                 g_set_error_literal (error,
 483                                      EV_DOCUMENT_ERROR,
 484                                      EV_DOCUMENT_ERROR_INVALID,
 485                                      _("File corrupted"));
 486                 return FALSE;
 487         }
 488
 489         /* FIXME: is this safe against filenames containing \n in the archive ? */
 490         cb_files = g_strsplit (std_out, EV_EOL, 0);
 491
 492         g_free (std_out);
 493
 494         if (!cb_files) {
 495                 g_set_error_literal (error,
 496                                      EV_DOCUMENT_ERROR,
 497                                      EV_DOCUMENT_ERROR_INVALID,
 498                                      _("No files in archive"));
 499                 return FALSE;
 500         }
 501
 502         comics_document->page_names = g_ptr_array_sized_new (64);
 503
 504         supported_extensions = get_supported_image_extensions ();
 505         for (i = 0; cb_files[i] != NULL; i++) {
 506                 if (comics_document->offset != NO_OFFSET) {
 507                         if (g_utf8_strlen (cb_files[i],-1) >
 508                             comics_document->offset) {
 509                                 cb_file =
 510                                         g_utf8_offset_to_pointer (cb_files[i],
 511                                                        comics_document->offset);
 512                         } else {
 513                                 continue;
 514                         }
 515                 } else {
 516                         cb_file = cb_files[i];
 517                 }
 518                 gchar *suffix = g_strrstr (cb_file, ".");
 519                 if (!suffix)
 520                         continue;
 521                 suffix = g_ascii_strdown (suffix + 1, -1);
 522                 if (g_slist_find_custom (supported_extensions, suffix,
 523                                          (GCompareFunc) strcmp) != NULL) {
 524                         g_ptr_array_add (comics_document->page_names,
 525                                          g_strstrip (g_strdup (cb_file)));
 526                 }
 527                 g_free (suffix);
 528         }
 529         g_strfreev (cb_files);
 530         g_slist_foreach (supported_extensions, (GFunc) g_free, NULL);
 531         g_slist_free (supported_extensions);
 532
 533         if (comics_document->page_names->len == 0) {
 534                 g_set_error (error,
 535                              EV_DOCUMENT_ERROR,
 536                              EV_DOCUMENT_ERROR_INVALID,
 537                              _("No images found in archive %s"),
 538                              uri);
 539                 return FALSE;
 540         }
 541
 542         /* Now sort the pages */
 543         g_ptr_array_sort (comics_document->page_names, sort_page_names);
 544
 545         return TRUE;
 546 }
 547
 548
 549 static gboolean
 550 comics_document_save (EvDocument *document,
 551                       const char *uri,
 552                       GError    **error)
 553 {
 554         ComicsDocument *comics_document = COMICS_DOCUMENT (document);
 555
 556         return ev_xfer_uri_simple (comics_document->archive, uri, error);
 557 }
 558
 559 static int
 560 comics_document_get_n_pages (EvDocument *document)
 561 {
 562         ComicsDocument *comics_document = COMICS_DOCUMENT (document);
 563
 564         if (comics_document->page_names == NULL)
 565                 return 0;
 566
 567         return comics_document->page_names->len;
 568 }
 569
 570 static void
 571 comics_document_get_page_size (EvDocument *document,
 572                                EvPage     *page,
 573                                double     *width,
 574                                double     *height)
 575 {
 576         GdkPixbufLoader *loader;
 577         char **argv;
 578         guchar buf[1024];
 579         gboolean success, got_size = FALSE;
 580         gint outpipe = -1;
 581         GPid child_pid;
 582         gssize bytes;
 583         GdkPixbuf *pixbuf;
 584         gchar *filename;
 585         ComicsDocument *comics_document = COMICS_DOCUMENT (document);
 586
 587         if (!comics_document->decompress_tmp) {
 588                 argv = extract_argv (document, page->index);
 589                 success = g_spawn_async_with_pipes (NULL, argv, NULL,
 590                                                     G_SPAWN_SEARCH_PATH |
 591                                                     G_SPAWN_STDERR_TO_DEV_NULL,
 592                                                     NULL, NULL,
 593                                                     &child_pid,
 594                                                     NULL, &outpipe, NULL, NULL);
 595                 g_strfreev (argv);
 596                 g_return_if_fail (success == TRUE);
 597
 598                 loader = gdk_pixbuf_loader_new ();
 599                 g_signal_connect (loader, "area-prepared",
 600                                   G_CALLBACK (get_page_size_area_prepared_cb),
 601                                   &got_size);
 602
 603                 while (outpipe >= 0) {
 604                         bytes = read (outpipe, buf, 1024);
 605
 606                         if (bytes > 0)
 607                         gdk_pixbuf_loader_write (loader, buf, bytes, NULL);
 608                         if (bytes <= 0 || got_size) {
 609                                 close (outpipe);
 610                                 outpipe = -1;
 611                                 gdk_pixbuf_loader_close (loader, NULL);
 612                         }
 613                 }
 614
 615                 if (gdk_pixbuf_loader_get_pixbuf (loader)) {
 616                         pixbuf = gdk_pixbuf_loader_get_pixbuf (loader);
 617                         if (width)
 618                                 *width = gdk_pixbuf_get_width (pixbuf);
 619                         if (height)
 620                                 *height = gdk_pixbuf_get_height (pixbuf);
 621                 }
 622
 623                 g_spawn_close_pid (child_pid);
 624                 g_object_unref (loader);
 625         } else {
 626                 filename = g_build_filename (comics_document->dir,
 627                                              (char *) comics_document->page_names->pdata[page->index],
 628                                              NULL);
 629                 pixbuf = gdk_pixbuf_new_from_file (filename, NULL);
 630                 g_free (filename);
 631                 if (width)
 632                         *width = gdk_pixbuf_get_width (pixbuf);
 633                 if (height)
 634                         *height = gdk_pixbuf_get_height (pixbuf);
 635         }
 636 }
 637
 638 static void
 639 get_page_size_area_prepared_cb (GdkPixbufLoader *loader,
 640                                 gpointer         data)
 641 {
 642         gboolean *got_size = data;
 643         *got_size = TRUE;
 644 }
 645
 646 static GdkPixbuf *
 647 comics_document_render_pixbuf (EvDocument      *document,
 648                                EvRenderContext *rc)
 649 {
 650         GdkPixbufLoader *loader;
 651         GdkPixbuf *rotated_pixbuf;
 652         char **argv;
 653         guchar buf[4096];
 654         gboolean success;
 655         gint outpipe = -1;
 656         GPid child_pid;
 657         gssize bytes;
 658         gint width, height;
 659         gchar *filename;
 660         ComicsDocument *comics_document = COMICS_DOCUMENT (document);
 661
 662         if (!comics_document->decompress_tmp) {
 663                 argv = extract_argv (document, rc->page->index);
 664                 success = g_spawn_async_with_pipes (NULL, argv, NULL,
 665                                                     G_SPAWN_SEARCH_PATH |
 666                                                     G_SPAWN_STDERR_TO_DEV_NULL,
 667                                                     NULL, NULL,
 668                                                     &child_pid,
 669                                                     NULL, &outpipe, NULL, NULL);
 670                 g_strfreev (argv);
 671                 g_return_val_if_fail (success == TRUE, NULL);
 672
 673                 loader = gdk_pixbuf_loader_new ();
 674                 g_signal_connect (loader, "size-prepared",
 675                                   G_CALLBACK (render_pixbuf_size_prepared_cb),
 676                                   &rc->scale);
 677
 678                 while (outpipe >= 0) {
 679                         bytes = read (outpipe, buf, 4096);
 680
 681                         if (bytes > 0) {
 682                                 gdk_pixbuf_loader_write (loader, buf, bytes,
 683                                 NULL);
 684                         } else if (bytes <= 0) {
 685                                 close (outpipe);
 686                                 gdk_pixbuf_loader_close (loader, NULL);
 687                                 outpipe = -1;
 688                         }
 689                 }
 690
 691                 rotated_pixbuf = gdk_pixbuf_rotate_simple (
 692                                         gdk_pixbuf_loader_get_pixbuf (loader),
 693                                         360 - rc->rotation);
 694                 g_spawn_close_pid (child_pid);
 695                 g_object_unref (loader);
 696         } else {
 697                 filename =
 698                         g_build_filename (comics_document->dir,
 699                                           (char *) comics_document->page_names->pdata[rc->page->index],
 700                                           NULL);
 701
 702                 gdk_pixbuf_get_file_info (filename, &width, &height);
 703
 704                 rotated_pixbuf =
 705                   gdk_pixbuf_rotate_simple (gdk_pixbuf_new_from_file_at_size (
 706                                             filename, width * (rc->scale) + 0.5,
 707                                             height * (rc->scale) + 0.5, NULL),
 708                                             360 - rc->rotation);
 709                 g_free (filename);
 710
 711         }
 712         return rotated_pixbuf;
 713 }
 714
 715 static cairo_surface_t *
 716 comics_document_render (EvDocument      *document,
 717                         EvRenderContext *rc)
 718 {
 719         GdkPixbuf       *pixbuf;
 720         cairo_surface_t *surface;
 721
 722         pixbuf = comics_document_render_pixbuf (document, rc);
 723         surface = ev_document_misc_surface_from_pixbuf (pixbuf);
 724         g_object_unref (pixbuf);
 725
 726         return surface;
 727 }
 728
 729 static void
 730 render_pixbuf_size_prepared_cb (GdkPixbufLoader *loader,
 731                                 gint             width,
 732                                 gint             height,
 733                                 gpointer         data)
 734 {
 735         double *scale = data;
 736         int w = (width  * (*scale) + 0.5);
 737         int h = (height * (*scale) + 0.5);
 738
 739         gdk_pixbuf_loader_set_size (loader, w, h);
 740 }
 741
 742 /**
 743  * comics_remove_dir: Removes a directory recursively.
 744  * Returns:
 745  *      0 if it was successfully deleted,
 746  *      -1 if an error occurred
 747  */
 748 static int
 749 comics_remove_dir (gchar *path_name)
 750 {
 751         GDir  *content_dir;
 752         const gchar *filename;
 753         gchar *filename_with_path;
 754
 755         if (g_file_test (path_name, G_FILE_TEST_IS_DIR)) {
 756                 content_dir = g_dir_open  (path_name, 0, NULL);
 757                 filename  = g_dir_read_name (content_dir);
 758                 while (filename) {
 759                         filename_with_path =
 760                                 g_build_filename (path_name,
 761                                                   filename, NULL);
 762                         comics_remove_dir (filename_with_path);
 763                         g_free (filename_with_path);
 764                         filename = g_dir_read_name (content_dir);
 765                 }
 766                 g_dir_close (content_dir);
 767         }
 768         /* Note from g_remove() documentation: on Windows, it is in general not
 769          * possible to remove a file that is open to some process, or mapped
 770          * into memory.*/
 771         return (g_remove (path_name));
 772 }
 773
 774 static void
 775 comics_document_finalize (GObject *object)
 776 {
 777         ComicsDocument *comics_document = COMICS_DOCUMENT (object);
 778
 779         if (comics_document->decompress_tmp) {
 780                 if (comics_remove_dir (comics_document->dir) == -1)
 781                         g_warning (_("There was an error deleting “%s”."),
 782                                    comics_document->dir);
 783                 g_free (comics_document->dir);
 784         }
 785
 786         if (comics_document->page_names) {
 787                 g_ptr_array_foreach (comics_document->page_names, (GFunc) g_free, NULL);
 788                 g_ptr_array_free (comics_document->page_names, TRUE);
 789         }
 790
 791         g_free (comics_document->archive);
 792         g_free (comics_document->selected_command);
 793         g_free (comics_document->alternative_command);
 794         g_free (comics_document->extract_command);
 795         g_free (comics_document->list_command);
 796
 797         G_OBJECT_CLASS (comics_document_parent_class)->finalize (object);
 798 }
 799
 800 static void
 801 comics_document_class_init (ComicsDocumentClass *klass)
 802 {
 803         GObjectClass    *gobject_class = G_OBJECT_CLASS (klass);
 804         EvDocumentClass *ev_document_class = EV_DOCUMENT_CLASS (klass);
 805
 806         gobject_class->finalize = comics_document_finalize;
 807
 808         ev_document_class->load = comics_document_load;
 809         ev_document_class->save = comics_document_save;
 810         ev_document_class->get_n_pages = comics_document_get_n_pages;
 811         ev_document_class->get_page_size = comics_document_get_page_size;
 812         ev_document_class->render = comics_document_render;
 813 }
 814
 815 static void
 816 comics_document_init (ComicsDocument *comics_document)
 817 {
 818         comics_document->archive = NULL;
 819         comics_document->page_names = NULL;
 820         comics_document->extract_command = NULL;
 821 }
 822
 823 /* Returns a list of file extensions supported by gdk-pixbuf */
 824 static GSList*
 825 get_supported_image_extensions()
 826 {
 827         GSList *extensions = NULL;
 828         GSList *formats = gdk_pixbuf_get_formats ();
 829         GSList *l;
 830
 831         for (l = formats; l != NULL; l = l->next) {
 832                 int i;
 833                 gchar **ext = gdk_pixbuf_format_get_extensions (l->data);
 834
 835                 for (i = 0; ext[i] != NULL; i++) {
 836                         extensions = g_slist_append (extensions,
 837                                                      g_strdup (ext[i]));
 838                 }
 839
 840                 g_strfreev (ext);
 841         }
 842
 843         g_slist_free (formats);
 844         return extensions;
 845 }
 846
 847 static char**
 848 extract_argv (EvDocument *document, gint page)
 849 {
 850         ComicsDocument *comics_document = COMICS_DOCUMENT (document);
 851         char **argv;
 852         char *command_line, *quoted_archive, *quoted_filename;
 853         GError *err = NULL;
 854
 855         if (page >= comics_document->page_names->len)
 856                 return NULL;
 857
 858         if (comics_document->regex_arg) {
 859                 quoted_archive = comics_regex_quote (comics_document->archive);
 860                 quoted_filename =
 861                         comics_regex_quote (comics_document->page_names->pdata[page]);
 862         } else {
 863                 quoted_archive = g_shell_quote (comics_document->archive);
 864                 quoted_filename = g_shell_quote (comics_document->page_names->pdata[page]);
 865         }
 866
 867         command_line = g_strdup_printf ("%s %s %s",
 868                                         comics_document->extract_command,
 869                                         quoted_archive,
 870                                         quoted_filename);
 871         g_shell_parse_argv (command_line, NULL, &argv, &err);
 872
 873         if (err) {
 874                 g_warning (_("Error %s"), err->message);
 875                 g_error_free (err);
 876                 return NULL;
 877         }
 878
 879         g_free (command_line);
 880         g_free (quoted_archive);
 881         g_free (quoted_filename);
 882         return argv;
 883 }