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   1 /* directory.cc - Results of directory-based searches from a notmuch database
   2  *
   3  * Copyright © 2009 Carl Worth
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program 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
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see http://www.gnu.org/licenses/ .
  17  *
  18  * Author: Carl Worth <cworth@cworth.org>
  19  */
  20
  21 #include "notmuch-private.h"
  22 #include "database-private.h"
  23
  24 #include <xapian.h>
  25
  26 struct _notmuch_filenames {
  27     Xapian::TermIterator iterator;
  28     Xapian::TermIterator end;
  29     int prefix_len;
  30     char *filename;
  31 };
  32
  33 /* We end up having to call the destructors explicitly because we had
  34  * to use "placement new" in order to initialize C++ objects within a
  35  * block that we allocated with talloc. So C++ is making talloc
  36  * slightly less simple to use, (we wouldn't need
  37  * talloc_set_destructor at all otherwise).
  38  */
  39 static int
  40 _notmuch_filenames_destructor (notmuch_filenames_t *filenames)
  41 {
  42     filenames->iterator.~TermIterator ();
  43     filenames->end.~TermIterator ();
  44
  45     return 0;
  46 }
  47
  48 /* Create an iterator to iterate over the basenames of files (or
  49  * directories) that all share a common parent directory.
  50  *
  51  * The code here is general enough to be reused for any case of
  52  * iterating over the non-prefixed portion of terms sharing a common
  53  * prefix.
  54  */
  55 notmuch_filenames_t *
  56 _notmuch_filenames_create (void *ctx,
  57                            notmuch_database_t *notmuch,
  58                            const char *prefix)
  59 {
  60     notmuch_filenames_t *filenames;
  61
  62     filenames = talloc (ctx, notmuch_filenames_t);
  63     if (unlikely (filenames == NULL))
  64         return NULL;
  65
  66     new (&filenames->iterator) Xapian::TermIterator ();
  67     new (&filenames->end) Xapian::TermIterator ();
  68
  69     talloc_set_destructor (filenames, _notmuch_filenames_destructor);
  70
  71     filenames->iterator = notmuch->xapian_db->allterms_begin (prefix);
  72     filenames->end = notmuch->xapian_db->allterms_end (prefix);
  73
  74     filenames->prefix_len = strlen (prefix);
  75
  76     filenames->filename = NULL;
  77
  78     return filenames;
  79 }
  80
  81 notmuch_bool_t
  82 notmuch_filenames_has_more (notmuch_filenames_t *filenames)
  83 {
  84     if (filenames == NULL)
  85         return NULL;
  86
  87     return (filenames->iterator != filenames->end);
  88 }
  89
  90 const char *
  91 notmuch_filenames_get (notmuch_filenames_t *filenames)
  92 {
  93     if (filenames == NULL || filenames->iterator == filenames->end)
  94         return NULL;
  95
  96     if (filenames->filename == NULL) {
  97         std::string term = *filenames->iterator;
  98
  99         filenames->filename = talloc_strdup (filenames,
 100                                              term.c_str () +
 101                                              filenames->prefix_len);
 102     }
 103
 104     return filenames->filename;
 105 }
 106
 107 void
 108 notmuch_filenames_advance (notmuch_filenames_t *filenames)
 109 {
 110     if (filenames == NULL)
 111         return;
 112
 113     if (filenames->filename) {
 114         talloc_free (filenames->filename);
 115         filenames->filename = NULL;
 116     }
 117
 118     if (filenames->iterator != filenames->end)
 119         filenames->iterator++;
 120 }
 121
 122 void
 123 notmuch_filenames_destroy (notmuch_filenames_t *filenames)
 124 {
 125     if (filenames == NULL)
 126         return;
 127
 128     talloc_free (filenames);
 129 }
 130
 131 struct _notmuch_directory {
 132     notmuch_database_t *notmuch;
 133     Xapian::docid document_id;
 134     Xapian::Document doc;
 135     time_t mtime;
 136 };
 137
 138 /* We end up having to call the destructor explicitly because we had
 139  * to use "placement new" in order to initialize C++ objects within a
 140  * block that we allocated with talloc. So C++ is making talloc
 141  * slightly less simple to use, (we wouldn't need
 142  * talloc_set_destructor at all otherwise).
 143  */
 144 static int
 145 _notmuch_directory_destructor (notmuch_directory_t *directory)
 146 {
 147     directory->doc.~Document ();
 148
 149     return 0;
 150 }
 151
 152 static notmuch_private_status_t
 153 find_directory_document (notmuch_database_t *notmuch,
 154                          const char *db_path,
 155                          Xapian::Document *document)
 156 {
 157     notmuch_private_status_t status;
 158     Xapian::docid doc_id;
 159
 160     status = _notmuch_database_find_unique_doc_id (notmuch, "directory",
 161                                                    db_path, &doc_id);
 162     if (status) {
 163         *document = Xapian::Document ();
 164         return status;
 165     }
 166
 167     *document = notmuch->xapian_db->get_document (doc_id);
 168     return NOTMUCH_PRIVATE_STATUS_SUCCESS;
 169 }
 170
 171 notmuch_directory_t *
 172 _notmuch_directory_create (notmuch_database_t *notmuch,
 173                            const char *path,
 174                            notmuch_status_t *status_ret)
 175 {
 176     Xapian::WritableDatabase *db;
 177     notmuch_directory_t *directory;
 178     notmuch_private_status_t private_status;
 179     const char *db_path;
 180
 181     *status_ret = NOTMUCH_STATUS_SUCCESS;
 182
 183     path = _notmuch_database_relative_path (notmuch, path);
 184
 185     if (notmuch->mode == NOTMUCH_DATABASE_MODE_READ_ONLY) {
 186         fprintf (stderr, "Attempted to update a read-only database.\n");
 187         *status_ret = NOTMUCH_STATUS_READONLY_DATABASE;
 188         return NULL;
 189     }
 190
 191     db = static_cast <Xapian::WritableDatabase *> (notmuch->xapian_db);
 192
 193     directory = talloc (notmuch, notmuch_directory_t);
 194     if (unlikely (directory == NULL))
 195         return NULL;
 196
 197     directory->notmuch = notmuch;
 198
 199     /* "placement new"---not actually allocating memory */
 200     new (&directory->doc) Xapian::Document;
 201
 202     talloc_set_destructor (directory, _notmuch_directory_destructor);
 203
 204     db_path = _notmuch_database_get_directory_db_path (path);
 205
 206     try {
 207         Xapian::TermIterator i, end;
 208
 209         private_status = find_directory_document (notmuch, db_path,
 210                                                   &directory->doc);
 211         directory->document_id = directory->doc.get_docid ();
 212
 213         if (private_status == NOTMUCH_PRIVATE_STATUS_NO_DOCUMENT_FOUND) {
 214             void *local = talloc_new (directory);
 215             const char *parent, *basename;
 216             Xapian::docid parent_id;
 217             char *term = talloc_asprintf (local, "%s%s",
 218                                           _find_prefix ("directory"), db_path);
 219             directory->doc.add_term (term);
 220
 221             directory->doc.set_data (path);
 222
 223             _notmuch_database_split_path (local, path, &parent, &basename);
 224
 225             _notmuch_database_find_directory_id (notmuch, parent, &parent_id);
 226
 227             if (basename) {
 228                 term = talloc_asprintf (local, "%s%u:%s",
 229                                         _find_prefix ("directory-direntry"),
 230                                         parent_id, basename);
 231                 directory->doc.add_term (term);
 232             }
 233
 234             directory->doc.add_value (NOTMUCH_VALUE_TIMESTAMP,
 235                                       Xapian::sortable_serialise (0));
 236
 237             directory->document_id = db->add_document (directory->doc);
 238             talloc_free (local);
 239         }
 240
 241         directory->mtime = Xapian::sortable_unserialise (
 242             directory->doc.get_value (NOTMUCH_VALUE_TIMESTAMP));
 243     } catch (const Xapian::Error &error) {
 244         fprintf (stderr,
 245                  "A Xapian exception occurred creating a directory: %s.\n",
 246                  error.get_msg().c_str());
 247         notmuch->exception_reported = TRUE;
 248         notmuch_directory_destroy (directory);
 249         *status_ret = NOTMUCH_STATUS_XAPIAN_EXCEPTION;
 250         return NULL;
 251     }
 252
 253     if (db_path != path)
 254         free ((char *) db_path);
 255
 256     return directory;
 257 }
 258
 259 unsigned int
 260 _notmuch_directory_get_document_id (notmuch_directory_t *directory)
 261 {
 262     return directory->document_id;
 263 }
 264
 265 notmuch_status_t
 266 notmuch_directory_set_mtime (notmuch_directory_t *directory,
 267                              time_t mtime)
 268 {
 269     notmuch_database_t *notmuch = directory->notmuch;
 270     Xapian::WritableDatabase *db;
 271
 272     if (notmuch->mode == NOTMUCH_DATABASE_MODE_READ_ONLY) {
 273         fprintf (stderr, "Attempted to update a read-only database.\n");
 274         return NOTMUCH_STATUS_READONLY_DATABASE;
 275     }
 276
 277     db = static_cast <Xapian::WritableDatabase *> (notmuch->xapian_db);
 278
 279     try {
 280         directory->doc.add_value (NOTMUCH_VALUE_TIMESTAMP,
 281                                    Xapian::sortable_serialise (mtime));
 282
 283         db->replace_document (directory->document_id, directory->doc);
 284     } catch (const Xapian::Error &error) {
 285         fprintf (stderr,
 286                  "A Xapian exception occurred setting directory mtime: %s.\n",
 287                  error.get_msg().c_str());
 288         notmuch->exception_reported = TRUE;
 289         return NOTMUCH_STATUS_XAPIAN_EXCEPTION;
 290     }
 291
 292     return NOTMUCH_STATUS_SUCCESS;
 293 }
 294
 295 time_t
 296 notmuch_directory_get_mtime (notmuch_directory_t *directory)
 297 {
 298     return directory->mtime;
 299 }
 300
 301 notmuch_filenames_t *
 302 notmuch_directory_get_child_files (notmuch_directory_t *directory)
 303 {
 304     char *term;
 305     notmuch_filenames_t *child_files;
 306
 307     term = talloc_asprintf (directory, "%s%u:",
 308                             _find_prefix ("file-direntry"),
 309                             directory->document_id);
 310
 311     child_files = _notmuch_filenames_create (directory,
 312                                              directory->notmuch, term);
 313
 314     talloc_free (term);
 315
 316     return child_files;
 317 }
 318
 319 notmuch_filenames_t *
 320 notmuch_directory_get_child_directories (notmuch_directory_t *directory)
 321 {
 322     char *term;
 323     notmuch_filenames_t *child_directories;
 324
 325     term = talloc_asprintf (directory, "%s%u:",
 326                             _find_prefix ("directory-direntry"),
 327                             directory->document_id);
 328
 329     child_directories = _notmuch_filenames_create (directory,
 330                                                    directory->notmuch, term);
 331
 332     talloc_free (term);
 333
 334     return child_directories;
 335 }
 336
 337 void
 338 notmuch_directory_destroy (notmuch_directory_t *directory)
 339 {
 340     talloc_free (directory);
 341 }