gio/gdummyfile.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2006-2007 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  *
  20  * Author: Alexander Larsson <alexl@redhat.com>
  21  */
  22
  23 #include "config.h"
  24
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <fcntl.h>
  30 #ifdef HAVE_UNISTD_H
  31 #include <unistd.h>
  32 #endif
  33 #include <stdlib.h>
  34
  35 #include "gdummyfile.h"
  36 #include "gfile.h"
  37
  38 #include "gioalias.h"
  39
  40 static void g_dummy_file_file_iface_init (GFileIface *iface);
  41
  42 typedef struct {
  43   char *scheme;
  44   char *userinfo;
  45   char *host;
  46   int port; /* -1 => not in uri */
  47   char *path;
  48   char *query;
  49   char *fragment;
  50 } GDecodedUri;
  51
  52 struct _GDummyFile
  53 {
  54   GObject parent_instance;
  55
  56   GDecodedUri *decoded_uri;
  57   char *text_uri;
  58 };
  59
  60 #define g_dummy_file_get_type _g_dummy_file_get_type
  61 G_DEFINE_TYPE_WITH_CODE (GDummyFile, g_dummy_file, G_TYPE_OBJECT,
  62                          G_IMPLEMENT_INTERFACE (G_TYPE_FILE,
  63                                                 g_dummy_file_file_iface_init))
  64
  65 #define SUB_DELIM_CHARS  "!$&'()*+,;="
  66
  67 static char *       _g_encode_uri       (GDecodedUri *decoded);
  68 static void         _g_decoded_uri_free (GDecodedUri *decoded);
  69 static GDecodedUri *_g_decode_uri       (const char  *uri);
  70 static GDecodedUri *_g_decoded_uri_new  (void);
  71
  72 static char * unescape_string (const gchar *escaped_string,
  73                                const gchar *escaped_string_end,
  74                                const gchar *illegal_characters);
  75
  76 static void g_string_append_encoded (GString    *string,
  77                                      const char *encoded,
  78                                      const char *reserved_chars_allowed);
  79
  80 static void
  81 g_dummy_file_finalize (GObject *object)
  82 {
  83   GDummyFile *dummy;
  84
  85   dummy = G_DUMMY_FILE (object);
  86
  87   if (dummy->decoded_uri)
  88     _g_decoded_uri_free (dummy->decoded_uri);
  89
  90   g_free (dummy->text_uri);
  91
  92   G_OBJECT_CLASS (g_dummy_file_parent_class)->finalize (object);
  93 }
  94
  95 static void
  96 g_dummy_file_class_init (GDummyFileClass *klass)
  97 {
  98   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  99
 100   gobject_class->finalize = g_dummy_file_finalize;
 101 }
 102
 103 static void
 104 g_dummy_file_init (GDummyFile *dummy)
 105 {
 106 }
 107
 108 /**
 109  * g_dummy_file_new:
 110  * @uri: Universal Resource Identifier for the dummy file object.
 111  *
 112  * Returns: a new #GFile.
 113  **/
 114 GFile *
 115 _g_dummy_file_new (const char *uri)
 116 {
 117   GDummyFile *dummy;
 118
 119   g_return_val_if_fail (uri != NULL, NULL);
 120
 121   dummy = g_object_new (G_TYPE_DUMMY_FILE, NULL);
 122   dummy->text_uri = g_strdup (uri);
 123   dummy->decoded_uri = _g_decode_uri (uri);
 124
 125   return G_FILE (dummy);
 126 }
 127
 128 static gboolean
 129 g_dummy_file_is_native (GFile *file)
 130 {
 131   return FALSE;
 132 }
 133
 134 static char *
 135 g_dummy_file_get_basename (GFile *file)
 136 {
 137   GDummyFile *dummy = G_DUMMY_FILE (file);
 138
 139   if (dummy->decoded_uri)
 140     return g_path_get_basename (dummy->decoded_uri->path);
 141   return g_strdup (dummy->text_uri);
 142 }
 143
 144 static char *
 145 g_dummy_file_get_path (GFile *file)
 146 {
 147   return NULL;
 148 }
 149
 150 static char *
 151 g_dummy_file_get_uri (GFile *file)
 152 {
 153   return g_strdup (G_DUMMY_FILE (file)->text_uri);
 154 }
 155
 156 static char *
 157 g_dummy_file_get_parse_name (GFile *file)
 158 {
 159   return g_strdup (G_DUMMY_FILE (file)->text_uri);
 160 }
 161
 162 static GFile *
 163 g_dummy_file_get_parent (GFile *file)
 164 {
 165   GDummyFile *dummy = G_DUMMY_FILE (file);
 166   GFile *parent;
 167   char *dirname;
 168   char *uri;
 169   GDecodedUri new_decoded_uri;
 170
 171   if (dummy->decoded_uri == NULL ||
 172       g_strcmp0 (dummy->decoded_uri->path, "/") == 0)
 173     return NULL;
 174
 175   dirname = g_path_get_dirname (dummy->decoded_uri->path);
 176
 177   if (strcmp (dirname, ".") == 0)
 178     {
 179       g_free (dirname);
 180       return NULL;
 181     }
 182
 183   new_decoded_uri = *dummy->decoded_uri;
 184   new_decoded_uri.path = dirname;
 185   uri = _g_encode_uri (&new_decoded_uri);
 186   g_free (dirname);
 187
 188   parent = _g_dummy_file_new (uri);
 189   g_free (uri);
 190
 191   return parent;
 192 }
 193
 194 static GFile *
 195 g_dummy_file_dup (GFile *file)
 196 {
 197   GDummyFile *dummy = G_DUMMY_FILE (file);
 198
 199   return _g_dummy_file_new (dummy->text_uri);
 200 }
 201
 202 static guint
 203 g_dummy_file_hash (GFile *file)
 204 {
 205   GDummyFile *dummy = G_DUMMY_FILE (file);
 206
 207   return g_str_hash (dummy->text_uri);
 208 }
 209
 210 static gboolean
 211 g_dummy_file_equal (GFile *file1,
 212                     GFile *file2)
 213 {
 214   GDummyFile *dummy1 = G_DUMMY_FILE (file1);
 215   GDummyFile *dummy2 = G_DUMMY_FILE (file2);
 216
 217   return g_str_equal (dummy1->text_uri, dummy2->text_uri);
 218 }
 219
 220 static int
 221 safe_strcmp (const char *a,
 222              const char *b)
 223 {
 224   if (a == NULL)
 225     a = "";
 226   if (b == NULL)
 227     b = "";
 228
 229   return strcmp (a, b);
 230 }
 231
 232 static gboolean
 233 uri_same_except_path (GDecodedUri *a,
 234                       GDecodedUri *b)
 235 {
 236   if (safe_strcmp (a->scheme, b->scheme) != 0)
 237     return FALSE;
 238   if (safe_strcmp (a->userinfo, b->userinfo) != 0)
 239     return FALSE;
 240   if (safe_strcmp (a->host, b->host) != 0)
 241     return FALSE;
 242   if (a->port != b->port)
 243     return FALSE;
 244
 245   return TRUE;
 246 }
 247
 248 static const char *
 249 match_prefix (const char *path,
 250               const char *prefix)
 251 {
 252   int prefix_len;
 253
 254   prefix_len = strlen (prefix);
 255   if (strncmp (path, prefix, prefix_len) != 0)
 256     return NULL;
 257   return path + prefix_len;
 258 }
 259
 260 static gboolean
 261 g_dummy_file_prefix_matches (GFile *parent, GFile *descendant)
 262 {
 263   GDummyFile *parent_dummy = G_DUMMY_FILE (parent);
 264   GDummyFile *descendant_dummy = G_DUMMY_FILE (descendant);
 265   const char *remainder;
 266
 267   if (parent_dummy->decoded_uri != NULL &&
 268       descendant_dummy->decoded_uri != NULL)
 269     {
 270       if (uri_same_except_path (parent_dummy->decoded_uri,
 271                                 descendant_dummy->decoded_uri))
 272         {
 273           remainder = match_prefix (descendant_dummy->decoded_uri->path,
 274                                     parent_dummy->decoded_uri->path);
 275           if (remainder != NULL && *remainder == '/')
 276             {
 277               while (*remainder == '/')
 278                 remainder++;
 279               if (*remainder != 0)
 280                 return TRUE;
 281             }
 282         }
 283     }
 284   else
 285     {
 286       remainder = match_prefix (descendant_dummy->text_uri,
 287                                 parent_dummy->text_uri);
 288       if (remainder != NULL && *remainder == '/')
 289           {
 290             while (*remainder == '/')
 291               remainder++;
 292             if (*remainder != 0)
 293               return TRUE;
 294           }
 295     }
 296
 297   return FALSE;
 298 }
 299
 300 static char *
 301 g_dummy_file_get_relative_path (GFile *parent,
 302                                 GFile *descendant)
 303 {
 304   GDummyFile *parent_dummy = G_DUMMY_FILE (parent);
 305   GDummyFile *descendant_dummy = G_DUMMY_FILE (descendant);
 306   const char *remainder;
 307
 308   if (parent_dummy->decoded_uri != NULL &&
 309       descendant_dummy->decoded_uri != NULL)
 310     {
 311       if (uri_same_except_path (parent_dummy->decoded_uri,
 312                                 descendant_dummy->decoded_uri))
 313         {
 314           remainder = match_prefix (descendant_dummy->decoded_uri->path,
 315                                     parent_dummy->decoded_uri->path);
 316           if (remainder != NULL && *remainder == '/')
 317             {
 318               while (*remainder == '/')
 319                 remainder++;
 320               if (*remainder != 0)
 321                 return g_strdup (remainder);
 322             }
 323         }
 324     }
 325   else
 326     {
 327       remainder = match_prefix (descendant_dummy->text_uri,
 328                                 parent_dummy->text_uri);
 329       if (remainder != NULL && *remainder == '/')
 330           {
 331             while (*remainder == '/')
 332               remainder++;
 333             if (*remainder != 0)
 334               return unescape_string (remainder, NULL, "/");
 335           }
 336     }
 337
 338   return NULL;
 339 }
 340
 341
 342 static GFile *
 343 g_dummy_file_resolve_relative_path (GFile      *file,
 344                                     const char *relative_path)
 345 {
 346   GDummyFile *dummy = G_DUMMY_FILE (file);
 347   GFile *child;
 348   char *uri;
 349   GDecodedUri new_decoded_uri;
 350   GString *str;
 351
 352   if (dummy->decoded_uri == NULL)
 353     {
 354       str = g_string_new (dummy->text_uri);
 355       g_string_append (str, "/");
 356       g_string_append_encoded (str, relative_path, SUB_DELIM_CHARS ":@/");
 357       child = _g_dummy_file_new (str->str);
 358       g_string_free (str, TRUE);
 359     }
 360   else
 361     {
 362       new_decoded_uri = *dummy->decoded_uri;
 363
 364       if (g_path_is_absolute (relative_path))
 365         new_decoded_uri.path = g_strdup (relative_path);
 366       else
 367         new_decoded_uri.path = g_build_filename (new_decoded_uri.path, relative_path, NULL);
 368
 369       uri = _g_encode_uri (&new_decoded_uri);
 370       g_free (new_decoded_uri.path);
 371
 372       child = _g_dummy_file_new (uri);
 373       g_free (uri);
 374     }
 375
 376   return child;
 377 }
 378
 379 static GFile *
 380 g_dummy_file_get_child_for_display_name (GFile        *file,
 381                                          const char   *display_name,
 382                                          GError      **error)
 383 {
 384   return g_file_get_child (file, display_name);
 385 }
 386
 387 static gboolean
 388 g_dummy_file_has_uri_scheme (GFile *file,
 389                              const char *uri_scheme)
 390 {
 391   GDummyFile *dummy = G_DUMMY_FILE (file);
 392
 393   if (dummy->decoded_uri)
 394     return g_ascii_strcasecmp (uri_scheme, dummy->decoded_uri->scheme) == 0;
 395   return FALSE;
 396 }
 397
 398 static char *
 399 g_dummy_file_get_uri_scheme (GFile *file)
 400 {
 401   GDummyFile *dummy = G_DUMMY_FILE (file);
 402
 403   if (dummy->decoded_uri)
 404     return g_strdup (dummy->decoded_uri->scheme);
 405
 406   return NULL;
 407 }
 408
 409
 410 static void
 411 g_dummy_file_file_iface_init (GFileIface *iface)
 412 {
 413   iface->dup = g_dummy_file_dup;
 414   iface->hash = g_dummy_file_hash;
 415   iface->equal = g_dummy_file_equal;
 416   iface->is_native = g_dummy_file_is_native;
 417   iface->has_uri_scheme = g_dummy_file_has_uri_scheme;
 418   iface->get_uri_scheme = g_dummy_file_get_uri_scheme;
 419   iface->get_basename = g_dummy_file_get_basename;
 420   iface->get_path = g_dummy_file_get_path;
 421   iface->get_uri = g_dummy_file_get_uri;
 422   iface->get_parse_name = g_dummy_file_get_parse_name;
 423   iface->get_parent = g_dummy_file_get_parent;
 424   iface->prefix_matches = g_dummy_file_prefix_matches;
 425   iface->get_relative_path = g_dummy_file_get_relative_path;
 426   iface->resolve_relative_path = g_dummy_file_resolve_relative_path;
 427   iface->get_child_for_display_name = g_dummy_file_get_child_for_display_name;
 428
 429   iface->supports_thread_contexts = TRUE;
 430 }
 431
 432 /* Uri handling helper functions: */
 433
 434 static int
 435 unescape_character (const char *scanner)
 436 {
 437   int first_digit;
 438   int second_digit;
 439
 440   first_digit = g_ascii_xdigit_value (*scanner++);
 441   if (first_digit < 0)
 442     return -1;
 443
 444   second_digit = g_ascii_xdigit_value (*scanner++);
 445   if (second_digit < 0)
 446     return -1;
 447
 448   return (first_digit << 4) | second_digit;
 449 }
 450
 451 static char *
 452 unescape_string (const gchar *escaped_string,
 453                  const gchar *escaped_string_end,
 454                  const gchar *illegal_characters)
 455 {
 456   const gchar *in;
 457   gchar *out, *result;
 458   gint character;
 459
 460   if (escaped_string == NULL)
 461     return NULL;
 462
 463   if (escaped_string_end == NULL)
 464     escaped_string_end = escaped_string + strlen (escaped_string);
 465
 466   result = g_malloc (escaped_string_end - escaped_string + 1);
 467
 468   out = result;
 469   for (in = escaped_string; in < escaped_string_end; in++)
 470     {
 471       character = *in;
 472       if (*in == '%')
 473         {
 474           in++;
 475           if (escaped_string_end - in < 2)
 476             {
 477               g_free (result);
 478               return NULL;
 479             }
 480
 481           character = unescape_character (in);
 482
 483           /* Check for an illegal character. We consider '\0' illegal here. */
 484           if (character <= 0 ||
 485               (illegal_characters != NULL &&
 486                strchr (illegal_characters, (char)character) != NULL))
 487             {
 488               g_free (result);
 489               return NULL;
 490             }
 491           in++; /* The other char will be eaten in the loop header */
 492         }
 493       *out++ = (char)character;
 494     }
 495
 496   *out = '\0';
 497   g_warn_if_fail (out - result <= strlen (escaped_string));
 498   return result;
 499 }
 500
 501 void
 502 _g_decoded_uri_free (GDecodedUri *decoded)
 503 {
 504   if (decoded == NULL)
 505     return;
 506
 507   g_free (decoded->scheme);
 508   g_free (decoded->query);
 509   g_free (decoded->fragment);
 510   g_free (decoded->userinfo);
 511   g_free (decoded->host);
 512   g_free (decoded->path);
 513   g_free (decoded);
 514 }
 515
 516 GDecodedUri *
 517 _g_decoded_uri_new (void)
 518 {
 519   GDecodedUri *uri;
 520
 521   uri = g_new0 (GDecodedUri, 1);
 522   uri->port = -1;
 523
 524   return uri;
 525 }
 526
 527 GDecodedUri *
 528 _g_decode_uri (const char *uri)
 529 {
 530   GDecodedUri *decoded;
 531   const char *p, *in, *hier_part_start, *hier_part_end, *query_start, *fragment_start;
 532   char *out;
 533   char c;
 534
 535   /* From RFC 3986 Decodes:
 536    * URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
 537    */
 538
 539   p = uri;
 540
 541   /* Decode scheme:
 542      scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
 543   */
 544
 545   if (!g_ascii_isalpha (*p))
 546     return NULL;
 547
 548   while (1)
 549     {
 550       c = *p++;
 551
 552       if (c == ':')
 553         break;
 554
 555       if (!(g_ascii_isalnum(c) ||
 556             c == '+' ||
 557             c == '-' ||
 558             c == '.'))
 559         return NULL;
 560     }
 561
 562   decoded = _g_decoded_uri_new ();
 563
 564   decoded->scheme = g_malloc (p - uri);
 565   out = decoded->scheme;
 566   for (in = uri; in < p - 1; in++)
 567     *out++ = g_ascii_tolower (*in);
 568   *out = 0;
 569
 570   hier_part_start = p;
 571
 572   query_start = strchr (p, '?');
 573   if (query_start)
 574     {
 575       hier_part_end = query_start++;
 576       fragment_start = strchr (query_start, '#');
 577       if (fragment_start)
 578         {
 579           decoded->query = g_strndup (query_start, fragment_start - query_start);
 580           decoded->fragment = g_strdup (fragment_start+1);
 581         }
 582       else
 583         {
 584           decoded->query = g_strdup (query_start);
 585           decoded->fragment = NULL;
 586         }
 587     }
 588   else
 589     {
 590       /* No query */
 591       decoded->query = NULL;
 592       fragment_start = strchr (p, '#');
 593       if (fragment_start)
 594         {
 595           hier_part_end = fragment_start++;
 596           decoded->fragment = g_strdup (fragment_start);
 597         }
 598       else
 599         {
 600           hier_part_end = p + strlen (p);
 601           decoded->fragment = NULL;
 602         }
 603     }
 604
 605   /*  3:
 606       hier-part   = "//" authority path-abempty
 607                   / path-absolute
 608                   / path-rootless
 609                   / path-empty
 610
 611   */
 612
 613   if (hier_part_start[0] == '/' &&
 614       hier_part_start[1] == '/')
 615     {
 616       const char *authority_start, *authority_end;
 617       const char *userinfo_start, *userinfo_end;
 618       const char *host_start, *host_end;
 619       const char *port_start;
 620
 621       authority_start = hier_part_start + 2;
 622       /* authority is always followed by / or nothing */
 623       authority_end = memchr (authority_start, '/', hier_part_end - authority_start);
 624       if (authority_end == NULL)
 625         authority_end = hier_part_end;
 626
 627       /* 3.2:
 628               authority   = [ userinfo "@" ] host [ ":" port ]
 629       */
 630
 631       userinfo_end = memchr (authority_start, '@', authority_end - authority_start);
 632       if (userinfo_end)
 633         {
 634           userinfo_start = authority_start;
 635           decoded->userinfo = unescape_string (userinfo_start, userinfo_end, NULL);
 636           if (decoded->userinfo == NULL)
 637             {
 638               _g_decoded_uri_free (decoded);
 639               return NULL;
 640             }
 641           host_start = userinfo_end + 1;
 642         }
 643       else
 644         host_start = authority_start;
 645
 646       port_start = memchr (host_start, ':', authority_end - host_start);
 647       if (port_start)
 648         {
 649           host_end = port_start++;
 650
 651           decoded->port = atoi(port_start);
 652         }
 653       else
 654         {
 655           host_end = authority_end;
 656           decoded->port = -1;
 657         }
 658
 659       decoded->host = g_strndup (host_start, host_end - host_start);
 660
 661       hier_part_start = authority_end;
 662     }
 663
 664   decoded->path = unescape_string (hier_part_start, hier_part_end, "/");
 665
 666   if (decoded->path == NULL)
 667     {
 668       _g_decoded_uri_free (decoded);
 669       return NULL;
 670     }
 671
 672   return decoded;
 673 }
 674
 675 static gboolean
 676 is_valid (char c, const char *reserved_chars_allowed)
 677 {
 678   if (g_ascii_isalnum (c) ||
 679       c == '-' ||
 680       c == '.' ||
 681       c == '_' ||
 682       c == '~')
 683     return TRUE;
 684
 685   if (reserved_chars_allowed &&
 686       strchr (reserved_chars_allowed, c) != NULL)
 687     return TRUE;
 688
 689   return FALSE;
 690 }
 691
 692 static void
 693 g_string_append_encoded (GString    *string,
 694                          const char *encoded,
 695                          const char *reserved_chars_allowed)
 696 {
 697   unsigned char c;
 698   const char *end;
 699   static const gchar hex[16] = "0123456789ABCDEF";
 700
 701   end = encoded + strlen (encoded);
 702
 703   while ((c = *encoded) != 0)
 704     {
 705       if (is_valid (c, reserved_chars_allowed))
 706         {
 707           g_string_append_c (string, c);
 708           encoded++;
 709         }
 710       else
 711         {
 712           g_string_append_c (string, '%');
 713           g_string_append_c (string, hex[((guchar)c) >> 4]);
 714           g_string_append_c (string, hex[((guchar)c) & 0xf]);
 715           encoded++;
 716         }
 717     }
 718 }
 719
 720 static char *
 721 _g_encode_uri (GDecodedUri *decoded)
 722 {
 723   GString *uri;
 724
 725   uri = g_string_new (NULL);
 726
 727   g_string_append (uri, decoded->scheme);
 728   g_string_append (uri, "://");
 729
 730   if (decoded->host != NULL)
 731     {
 732       if (decoded->userinfo)
 733         {
 734           /* userinfo    = *( unreserved / pct-encoded / sub-delims / ":" ) */
 735           g_string_append_encoded (uri, decoded->userinfo, SUB_DELIM_CHARS ":");
 736           g_string_append_c (uri, '@');
 737         }
 738
 739       g_string_append (uri, decoded->host);
 740
 741       if (decoded->port != -1)
 742         {
 743           g_string_append_c (uri, ':');
 744           g_string_append_printf (uri, "%d", decoded->port);
 745         }
 746     }
 747
 748   g_string_append_encoded (uri, decoded->path, SUB_DELIM_CHARS ":@/");
 749
 750   if (decoded->query)
 751     {
 752       g_string_append_c (uri, '?');
 753       g_string_append (uri, decoded->query);
 754     }
 755
 756   if (decoded->fragment)
 757     {
 758       g_string_append_c (uri, '#');
 759       g_string_append (uri, decoded->fragment);
 760     }
 761
 762   return g_string_free (uri, FALSE);
 763 }