1 /* notmuch - Not much of an email library, (just index and search)
3 * Copyright © 2009 Carl Worth
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.
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.
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/ .
18 * Author: Carl Worth <cworth@cworth.org>
22 * @defgroup notmuch The notmuch API
24 * Not much of an email library, (just index and search)
35 # define NOTMUCH_BEGIN_DECLS extern "C" {
36 # define NOTMUCH_END_DECLS }
38 # define NOTMUCH_BEGIN_DECLS
39 # define NOTMUCH_END_DECLS
55 * The library version number. This must agree with the soname
56 * version in Makefile.local.
58 #define LIBNOTMUCH_MAJOR_VERSION 4
59 #define LIBNOTMUCH_MINOR_VERSION 3
60 #define LIBNOTMUCH_MICRO_VERSION 0
62 #define NOTMUCH_DEPRECATED(major,minor) \
63 __attribute__ ((deprecated ("function deprecated as of libnotmuch " #major "." #minor)))
64 #endif /* __DOXYGEN__ */
67 * Check the version of the notmuch library being compiled against.
69 * Return true if the library being compiled against is of the
70 * specified version or above. For example:
73 * #if LIBNOTMUCH_CHECK_VERSION(3, 1, 0)
74 * (code requiring libnotmuch 3.1.0 or above)
78 * LIBNOTMUCH_CHECK_VERSION has been defined since version 3.1.0; to
79 * check for versions prior to that, use:
82 * #if !defined(NOTMUCH_CHECK_VERSION)
83 * (code requiring libnotmuch prior to 3.1.0)
87 #define LIBNOTMUCH_CHECK_VERSION (major, minor, micro) \
88 (LIBNOTMUCH_MAJOR_VERSION > (major) || \
89 (LIBNOTMUCH_MAJOR_VERSION == (major) && LIBNOTMUCH_MINOR_VERSION > (minor)) || \
90 (LIBNOTMUCH_MAJOR_VERSION == (major) && LIBNOTMUCH_MINOR_VERSION == (minor) && \
91 LIBNOTMUCH_MICRO_VERSION >= (micro)))
94 * Notmuch boolean type.
96 typedef int notmuch_bool_t;
99 * Status codes used for the return values of most functions.
101 * A zero value (NOTMUCH_STATUS_SUCCESS) indicates that the function
102 * completed without error. Any other value indicates an error.
104 typedef enum _notmuch_status {
108 NOTMUCH_STATUS_SUCCESS = 0,
112 NOTMUCH_STATUS_OUT_OF_MEMORY,
114 * An attempt was made to write to a database opened in read-only
117 NOTMUCH_STATUS_READ_ONLY_DATABASE,
119 * A Xapian exception occurred.
121 NOTMUCH_STATUS_XAPIAN_EXCEPTION,
123 * An error occurred trying to read or write to a file (this could
124 * be file not found, permission denied, etc.)
126 * @todo We don't really want to expose this lame XAPIAN_EXCEPTION
127 * value. Instead we should map to things like DATABASE_LOCKED or
130 NOTMUCH_STATUS_FILE_ERROR,
132 * A file was presented that doesn't appear to be an email
135 NOTMUCH_STATUS_FILE_NOT_EMAIL,
137 * A file contains a message ID that is identical to a message
138 * already in the database.
140 NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID,
142 * The user erroneously passed a NULL pointer to a notmuch
145 NOTMUCH_STATUS_NULL_POINTER,
147 * A tag value is too long (exceeds NOTMUCH_TAG_MAX).
149 NOTMUCH_STATUS_TAG_TOO_LONG,
151 * The notmuch_message_thaw function has been called more times
152 * than notmuch_message_freeze.
154 NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW,
156 * notmuch_database_end_atomic has been called more times than
157 * notmuch_database_begin_atomic.
159 NOTMUCH_STATUS_UNBALANCED_ATOMIC,
161 * The operation is not supported.
163 NOTMUCH_STATUS_UNSUPPORTED_OPERATION,
165 * The operation requires a database upgrade.
167 NOTMUCH_STATUS_UPGRADE_REQUIRED,
169 * There is a problem with the proposed path, e.g. a relative path
170 * passed to a function expecting an absolute path.
172 NOTMUCH_STATUS_PATH_ERROR,
174 * Not an actual status value. Just a way to find out how many
175 * valid status values there are.
177 NOTMUCH_STATUS_LAST_STATUS
181 * Get a string representation of a notmuch_status_t value.
183 * The result is read-only.
186 notmuch_status_to_string (notmuch_status_t status);
188 /* Various opaque data types. For each notmuch_<foo>_t see the various
189 * notmuch_<foo> functions below. */
191 typedef struct _notmuch_database notmuch_database_t;
192 typedef struct _notmuch_query notmuch_query_t;
193 typedef struct _notmuch_threads notmuch_threads_t;
194 typedef struct _notmuch_thread notmuch_thread_t;
195 typedef struct _notmuch_messages notmuch_messages_t;
196 typedef struct _notmuch_message notmuch_message_t;
197 typedef struct _notmuch_tags notmuch_tags_t;
198 typedef struct _notmuch_directory notmuch_directory_t;
199 typedef struct _notmuch_filenames notmuch_filenames_t;
200 #endif /* __DOXYGEN__ */
203 * Create a new, empty notmuch database located at 'path'.
205 * The path should be a top-level directory to a collection of
206 * plain-text email messages (one message per file). This call will
207 * create a new ".notmuch" directory within 'path' where notmuch will
210 * After a successful call to notmuch_database_create, the returned
211 * database will be open so the caller should call
212 * notmuch_database_destroy when finished with it.
214 * The database will not yet have any data in it
215 * (notmuch_database_create itself is a very cheap function). Messages
216 * contained within 'path' can be added to the database by calling
217 * notmuch_database_add_message.
219 * In case of any failure, this function returns an error status and
220 * sets *database to NULL (after printing an error message on stderr).
224 * NOTMUCH_STATUS_SUCCESS: Successfully created the database.
226 * NOTMUCH_STATUS_NULL_POINTER: The given 'path' argument is NULL.
228 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory.
230 * NOTMUCH_STATUS_FILE_ERROR: An error occurred trying to create the
231 * database file (such as permission denied, or file not found,
232 * etc.), or the database already exists.
234 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred.
237 notmuch_database_create (const char *path, notmuch_database_t **database);
240 * Like notmuch_database_create, except optionally return an error
241 * message. This message is allocated by malloc and should be freed by
245 notmuch_database_create_verbose (const char *path,
246 notmuch_database_t **database,
247 char **error_message);
250 * Database open mode for notmuch_database_open.
254 * Open database for reading only.
256 NOTMUCH_DATABASE_MODE_READ_ONLY = 0,
258 * Open database for reading and writing.
260 NOTMUCH_DATABASE_MODE_READ_WRITE
261 } notmuch_database_mode_t;
264 * Open an existing notmuch database located at 'path'.
266 * The database should have been created at some time in the past,
267 * (not necessarily by this process), by calling
268 * notmuch_database_create with 'path'. By default the database should be
269 * opened for reading only. In order to write to the database you need to
270 * pass the NOTMUCH_DATABASE_MODE_READ_WRITE mode.
272 * An existing notmuch database can be identified by the presence of a
273 * directory named ".notmuch" below 'path'.
275 * The caller should call notmuch_database_destroy when finished with
278 * In case of any failure, this function returns an error status and
279 * sets *database to NULL (after printing an error message on stderr).
283 * NOTMUCH_STATUS_SUCCESS: Successfully opened the database.
285 * NOTMUCH_STATUS_NULL_POINTER: The given 'path' argument is NULL.
287 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory.
289 * NOTMUCH_STATUS_FILE_ERROR: An error occurred trying to open the
290 * database file (such as permission denied, or file not found,
291 * etc.), or the database version is unknown.
293 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred.
296 notmuch_database_open (const char *path,
297 notmuch_database_mode_t mode,
298 notmuch_database_t **database);
300 * Like notmuch_database_open, except optionally return an error
301 * message. This message is allocated by malloc and should be freed by
306 notmuch_database_open_verbose (const char *path,
307 notmuch_database_mode_t mode,
308 notmuch_database_t **database,
309 char **error_message);
312 * Retrieve last status string for given database.
316 notmuch_database_status_string (const notmuch_database_t *notmuch);
319 * Commit changes and close the given notmuch database.
321 * After notmuch_database_close has been called, calls to other
322 * functions on objects derived from this database may either behave
323 * as if the database had not been closed (e.g., if the required data
324 * has been cached) or may fail with a
325 * NOTMUCH_STATUS_XAPIAN_EXCEPTION.
327 * notmuch_database_close can be called multiple times. Later calls
330 * For writable databases, notmuch_database_close commits all changes
331 * to disk before closing the database. If the caller is currently in
332 * an atomic section (there was a notmuch_database_begin_atomic
333 * without a matching notmuch_database_end_atomic), this will discard
334 * changes made in that atomic section (but still commit changes made
335 * prior to entering the atomic section).
339 * NOTMUCH_STATUS_SUCCESS: Successfully closed the database.
341 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred; the
342 * database has been closed but there are no guarantees the
343 * changes to the database, if any, have been flushed to disk.
346 notmuch_database_close (notmuch_database_t *database);
349 * A callback invoked by notmuch_database_compact to notify the user
350 * of the progress of the compaction process.
352 typedef void (*notmuch_compact_status_cb_t)(const char *message, void *closure);
355 * Compact a notmuch database, backing up the original database to the
358 * The database will be opened with NOTMUCH_DATABASE_MODE_READ_WRITE
359 * during the compaction process to ensure no writes are made.
361 * If the optional callback function 'status_cb' is non-NULL, it will
362 * be called with diagnostic and informational messages. The argument
363 * 'closure' is passed verbatim to any callback invoked.
366 notmuch_database_compact (const char* path,
367 const char* backup_path,
368 notmuch_compact_status_cb_t status_cb,
372 * Destroy the notmuch database, closing it if necessary and freeing
373 * all associated resources.
375 * Return value as in notmuch_database_close if the database was open;
376 * notmuch_database_destroy itself has no failure modes.
379 notmuch_database_destroy (notmuch_database_t *database);
382 * Return the database path of the given database.
384 * The return value is a string owned by notmuch so should not be
385 * modified nor freed by the caller.
388 notmuch_database_get_path (notmuch_database_t *database);
391 * Return the database format version of the given database.
394 notmuch_database_get_version (notmuch_database_t *database);
397 * Can the database be upgraded to a newer database version?
399 * If this function returns TRUE, then the caller may call
400 * notmuch_database_upgrade to upgrade the database. If the caller
401 * does not upgrade an out-of-date database, then some functions may
402 * fail with NOTMUCH_STATUS_UPGRADE_REQUIRED. This always returns
403 * FALSE for a read-only database because there's no way to upgrade a
404 * read-only database.
407 notmuch_database_needs_upgrade (notmuch_database_t *database);
410 * Upgrade the current database to the latest supported version.
412 * This ensures that all current notmuch functionality will be
413 * available on the database. After opening a database in read-write
414 * mode, it is recommended that clients check if an upgrade is needed
415 * (notmuch_database_needs_upgrade) and if so, upgrade with this
416 * function before making any modifications. If
417 * notmuch_database_needs_upgrade returns FALSE, this will be a no-op.
419 * The optional progress_notify callback can be used by the caller to
420 * provide progress indication to the user. If non-NULL it will be
421 * called periodically with 'progress' as a floating-point value in
422 * the range of [0.0 .. 1.0] indicating the progress made so far in
423 * the upgrade process. The argument 'closure' is passed verbatim to
424 * any callback invoked.
427 notmuch_database_upgrade (notmuch_database_t *database,
428 void (*progress_notify) (void *closure,
433 * Begin an atomic database operation.
435 * Any modifications performed between a successful begin and a
436 * notmuch_database_end_atomic will be applied to the database
437 * atomically. Note that, unlike a typical database transaction, this
438 * only ensures atomicity, not durability; neither begin nor end
439 * necessarily flush modifications to disk.
441 * Atomic sections may be nested. begin_atomic and end_atomic must
442 * always be called in pairs.
446 * NOTMUCH_STATUS_SUCCESS: Successfully entered atomic section.
448 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred;
449 * atomic section not entered.
452 notmuch_database_begin_atomic (notmuch_database_t *notmuch);
455 * Indicate the end of an atomic database operation.
459 * NOTMUCH_STATUS_SUCCESS: Successfully completed atomic section.
461 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred;
462 * atomic section not ended.
464 * NOTMUCH_STATUS_UNBALANCED_ATOMIC: The database is not currently in
468 notmuch_database_end_atomic (notmuch_database_t *notmuch);
471 * Return the committed database revision and UUID.
473 * The database revision number increases monotonically with each
474 * commit to the database. Hence, all messages and message changes
475 * committed to the database (that is, visible to readers) have a last
476 * modification revision <= the committed database revision. Any
477 * messages committed in the future will be assigned a modification
478 * revision > the committed database revision.
480 * The UUID is a NUL-terminated opaque string that uniquely identifies
481 * this database. Two revision numbers are only comparable if they
482 * have the same database UUID.
485 notmuch_database_get_revision (notmuch_database_t *notmuch,
489 * Retrieve a directory object from the database for 'path'.
491 * Here, 'path' should be a path relative to the path of 'database'
492 * (see notmuch_database_get_path), or else should be an absolute path
493 * with initial components that match the path of 'database'.
495 * If this directory object does not exist in the database, this
496 * returns NOTMUCH_STATUS_SUCCESS and sets *directory to NULL.
498 * Otherwise the returned directory object is owned by the database
499 * and as such, will only be valid until notmuch_database_destroy is
504 * NOTMUCH_STATUS_SUCCESS: Successfully retrieved directory.
506 * NOTMUCH_STATUS_NULL_POINTER: The given 'directory' argument is NULL.
508 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred;
509 * directory not retrieved.
511 * NOTMUCH_STATUS_UPGRADE_REQUIRED: The caller must upgrade the
512 * database to use this function.
515 notmuch_database_get_directory (notmuch_database_t *database,
517 notmuch_directory_t **directory);
520 * Add a new message to the given notmuch database or associate an
521 * additional filename with an existing message.
523 * Here, 'filename' should be a path relative to the path of
524 * 'database' (see notmuch_database_get_path), or else should be an
525 * absolute filename with initial components that match the path of
528 * The file should be a single mail message (not a multi-message mbox)
529 * that is expected to remain at its current location, (since the
530 * notmuch database will reference the filename, and will not copy the
531 * entire contents of the file.
533 * If another message with the same message ID already exists in the
534 * database, rather than creating a new message, this adds 'filename'
535 * to the list of the filenames for the existing message.
537 * If 'message' is not NULL, then, on successful return
538 * (NOTMUCH_STATUS_SUCCESS or NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID) '*message'
539 * will be initialized to a message object that can be used for things
540 * such as adding tags to the just-added message. The user should call
541 * notmuch_message_destroy when done with the message. On any failure
542 * '*message' will be set to NULL.
546 * NOTMUCH_STATUS_SUCCESS: Message successfully added to database.
548 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred,
551 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: Message has the same message
552 * ID as another message already in the database. The new
553 * filename was successfully added to the message in the database
554 * (if not already present) and the existing message is returned.
556 * NOTMUCH_STATUS_FILE_ERROR: an error occurred trying to open the
557 * file, (such as permission denied, or file not found,
558 * etc.). Nothing added to the database.
560 * NOTMUCH_STATUS_FILE_NOT_EMAIL: the contents of filename don't look
561 * like an email message. Nothing added to the database.
563 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
564 * mode so no message can be added.
566 * NOTMUCH_STATUS_UPGRADE_REQUIRED: The caller must upgrade the
567 * database to use this function.
570 notmuch_database_add_message (notmuch_database_t *database,
571 const char *filename,
572 notmuch_message_t **message);
575 * Remove a message filename from the given notmuch database. If the
576 * message has no more filenames, remove the message.
578 * If the same message (as determined by the message ID) is still
579 * available via other filenames, then the message will persist in the
580 * database for those filenames. When the last filename is removed for
581 * a particular message, the database content for that message will be
586 * NOTMUCH_STATUS_SUCCESS: The last filename was removed and the
587 * message was removed from the database.
589 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred,
590 * message not removed.
592 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: This filename was removed but
593 * the message persists in the database with at least one other
596 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
597 * mode so no message can be removed.
599 * NOTMUCH_STATUS_UPGRADE_REQUIRED: The caller must upgrade the
600 * database to use this function.
603 notmuch_database_remove_message (notmuch_database_t *database,
604 const char *filename);
607 * Find a message with the given message_id.
609 * If a message with the given message_id is found then, on successful return
610 * (NOTMUCH_STATUS_SUCCESS) '*message' will be initialized to a message
611 * object. The caller should call notmuch_message_destroy when done with the
614 * On any failure or when the message is not found, this function initializes
615 * '*message' to NULL. This means, when NOTMUCH_STATUS_SUCCESS is returned, the
616 * caller is supposed to check '*message' for NULL to find out whether the
617 * message with the given message_id was found.
621 * NOTMUCH_STATUS_SUCCESS: Successful return, check '*message'.
623 * NOTMUCH_STATUS_NULL_POINTER: The given 'message' argument is NULL
625 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory, creating message object
627 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred
630 notmuch_database_find_message (notmuch_database_t *database,
631 const char *message_id,
632 notmuch_message_t **message);
635 * Find a message with the given filename.
637 * If the database contains a message with the given filename then, on
638 * successful return (NOTMUCH_STATUS_SUCCESS) '*message' will be initialized to
639 * a message object. The caller should call notmuch_message_destroy when done
642 * On any failure or when the message is not found, this function initializes
643 * '*message' to NULL. This means, when NOTMUCH_STATUS_SUCCESS is returned, the
644 * caller is supposed to check '*message' for NULL to find out whether the
645 * message with the given filename is found.
649 * NOTMUCH_STATUS_SUCCESS: Successful return, check '*message'
651 * NOTMUCH_STATUS_NULL_POINTER: The given 'message' argument is NULL
653 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory, creating the message object
655 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred
657 * NOTMUCH_STATUS_UPGRADE_REQUIRED: The caller must upgrade the
658 * database to use this function.
661 notmuch_database_find_message_by_filename (notmuch_database_t *notmuch,
662 const char *filename,
663 notmuch_message_t **message);
666 * Return a list of all tags found in the database.
668 * This function creates a list of all tags found in the database. The
669 * resulting list contains all tags from all messages found in the database.
671 * On error this function returns NULL.
674 notmuch_database_get_all_tags (notmuch_database_t *db);
677 * Create a new query for 'database'.
679 * Here, 'database' should be an open database, (see
680 * notmuch_database_open and notmuch_database_create).
682 * For the query string, we'll document the syntax here more
683 * completely in the future, but it's likely to be a specialized
684 * version of the general Xapian query syntax:
686 * http://xapian.org/docs/queryparser.html
688 * As a special case, passing either a length-zero string, (that is ""),
689 * or a string consisting of a single asterisk (that is "*"), will
690 * result in a query that returns all messages in the database.
692 * See notmuch_query_set_sort for controlling the order of results.
693 * See notmuch_query_search_messages and notmuch_query_search_threads
694 * to actually execute the query.
696 * User should call notmuch_query_destroy when finished with this
699 * Will return NULL if insufficient memory is available.
702 notmuch_query_create (notmuch_database_t *database,
703 const char *query_string);
706 * Sort values for notmuch_query_set_sort.
712 NOTMUCH_SORT_OLDEST_FIRST,
716 NOTMUCH_SORT_NEWEST_FIRST,
718 * Sort by message-id.
720 NOTMUCH_SORT_MESSAGE_ID,
724 NOTMUCH_SORT_UNSORTED
728 * Return the query_string of this query. See notmuch_query_create.
731 notmuch_query_get_query_string (const notmuch_query_t *query);
734 * Return the notmuch database of this query. See notmuch_query_create.
737 notmuch_query_get_database (const notmuch_query_t *query);
740 * Exclude values for notmuch_query_set_omit_excluded. The strange
741 * order is to maintain backward compatibility: the old FALSE/TRUE
742 * options correspond to the new
743 * NOTMUCH_EXCLUDE_FLAG/NOTMUCH_EXCLUDE_TRUE options.
746 NOTMUCH_EXCLUDE_FLAG,
747 NOTMUCH_EXCLUDE_TRUE,
748 NOTMUCH_EXCLUDE_FALSE,
753 * Specify whether to omit excluded results or simply flag them. By
754 * default, this is set to TRUE.
756 * If set to TRUE or ALL, notmuch_query_search_messages will omit excluded
757 * messages from the results, and notmuch_query_search_threads will omit
758 * threads that match only in excluded messages. If set to TRUE,
759 * notmuch_query_search_threads will include all messages in threads that
760 * match in at least one non-excluded message. Otherwise, if set to ALL,
761 * notmuch_query_search_threads will omit excluded messages from all threads.
763 * If set to FALSE or FLAG then both notmuch_query_search_messages and
764 * notmuch_query_search_threads will return all matching
765 * messages/threads regardless of exclude status. If set to FLAG then
766 * the exclude flag will be set for any excluded message that is
767 * returned by notmuch_query_search_messages, and the thread counts
768 * for threads returned by notmuch_query_search_threads will be the
769 * number of non-excluded messages/matches. Otherwise, if set to
770 * FALSE, then the exclude status is completely ignored.
772 * The performance difference when calling
773 * notmuch_query_search_messages should be relatively small (and both
774 * should be very fast). However, in some cases,
775 * notmuch_query_search_threads is very much faster when omitting
776 * excluded messages as it does not need to construct the threads that
777 * only match in excluded messages.
780 notmuch_query_set_omit_excluded (notmuch_query_t *query,
781 notmuch_exclude_t omit_excluded);
784 * Specify the sorting desired for this query.
787 notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort);
790 * Return the sort specified for this query. See
791 * notmuch_query_set_sort.
794 notmuch_query_get_sort (const notmuch_query_t *query);
797 * Add a tag that will be excluded from the query results by default.
798 * This exclusion will be overridden if this tag appears explicitly in
802 notmuch_query_add_tag_exclude (notmuch_query_t *query, const char *tag);
805 * Execute a query for threads, returning a notmuch_threads_t object
806 * which can be used to iterate over the results. The returned threads
807 * object is owned by the query and as such, will only be valid until
808 * notmuch_query_destroy.
810 * Typical usage might be:
812 * notmuch_query_t *query;
813 * notmuch_threads_t *threads;
814 * notmuch_thread_t *thread;
816 * query = notmuch_query_create (database, query_string);
818 * for (threads = notmuch_query_search_threads (query);
819 * notmuch_threads_valid (threads);
820 * notmuch_threads_move_to_next (threads))
822 * thread = notmuch_threads_get (threads);
824 * notmuch_thread_destroy (thread);
827 * notmuch_query_destroy (query);
829 * Note: If you are finished with a thread before its containing
830 * query, you can call notmuch_thread_destroy to clean up some memory
831 * sooner (as in the above example). Otherwise, if your thread objects
832 * are long-lived, then you don't need to call notmuch_thread_destroy
833 * and all the memory will still be reclaimed when the query is
836 * Note that there's no explicit destructor needed for the
837 * notmuch_threads_t object. (For consistency, we do provide a
838 * notmuch_threads_destroy function, but there's no good reason
839 * to call it if the query is about to be destroyed).
841 * @since libnotmuch 4.2 (notmuch 0.20)
844 notmuch_query_search_threads_st (notmuch_query_t *query,
845 notmuch_threads_t **out);
848 * Like notmuch_query_search_threads_st, but without a status return.
850 * If a Xapian exception occurs this function will return NULL.
852 * @deprecated Deprecated as of libnotmuch 4.3 (notmuch 0.21). Please
853 * use notmuch_query_search_threads_st instead.
856 NOTMUCH_DEPRECATED(4,3)
858 notmuch_query_search_threads (notmuch_query_t *query);
861 * Execute a query for messages, returning a notmuch_messages_t object
862 * which can be used to iterate over the results. The returned
863 * messages object is owned by the query and as such, will only be
864 * valid until notmuch_query_destroy.
866 * Typical usage might be:
868 * notmuch_query_t *query;
869 * notmuch_messages_t *messages;
870 * notmuch_message_t *message;
872 * query = notmuch_query_create (database, query_string);
874 * for (messages = notmuch_query_search_messages (query);
875 * notmuch_messages_valid (messages);
876 * notmuch_messages_move_to_next (messages))
878 * message = notmuch_messages_get (messages);
880 * notmuch_message_destroy (message);
883 * notmuch_query_destroy (query);
885 * Note: If you are finished with a message before its containing
886 * query, you can call notmuch_message_destroy to clean up some memory
887 * sooner (as in the above example). Otherwise, if your message
888 * objects are long-lived, then you don't need to call
889 * notmuch_message_destroy and all the memory will still be reclaimed
890 * when the query is destroyed.
892 * Note that there's no explicit destructor needed for the
893 * notmuch_messages_t object. (For consistency, we do provide a
894 * notmuch_messages_destroy function, but there's no good
895 * reason to call it if the query is about to be destroyed).
897 * If a Xapian exception occurs this function will return NULL.
899 * @since libnotmuch 4.2 (notmuch 0.20)
902 notmuch_query_search_messages_st (notmuch_query_t *query,
903 notmuch_messages_t **out);
905 * Like notmuch_query_search_messages, but without a status return.
907 * If a Xapian exception occurs this function will return NULL.
909 * @deprecated Deprecated as of libnotmuch 4.3 (notmuch 0.21). Please use
910 * notmuch_query_search_messages_st instead.
913 NOTMUCH_DEPRECATED(4,3)
915 notmuch_query_search_messages (notmuch_query_t *query);
918 * Destroy a notmuch_query_t along with any associated resources.
920 * This will in turn destroy any notmuch_threads_t and
921 * notmuch_messages_t objects generated by this query, (and in
922 * turn any notmuch_thread_t and notmuch_message_t objects generated
923 * from those results, etc.), if such objects haven't already been
927 notmuch_query_destroy (notmuch_query_t *query);
930 * Is the given 'threads' iterator pointing at a valid thread.
932 * When this function returns TRUE, notmuch_threads_get will return a
933 * valid object. Whereas when this function returns FALSE,
934 * notmuch_threads_get will return NULL.
936 * If passed a NULL pointer, this function returns FALSE
938 * See the documentation of notmuch_query_search_threads for example
939 * code showing how to iterate over a notmuch_threads_t object.
942 notmuch_threads_valid (notmuch_threads_t *threads);
945 * Get the current thread from 'threads' as a notmuch_thread_t.
947 * Note: The returned thread belongs to 'threads' and has a lifetime
948 * identical to it (and the query to which it belongs).
950 * See the documentation of notmuch_query_search_threads for example
951 * code showing how to iterate over a notmuch_threads_t object.
953 * If an out-of-memory situation occurs, this function will return
957 notmuch_threads_get (notmuch_threads_t *threads);
960 * Move the 'threads' iterator to the next thread.
962 * If 'threads' is already pointing at the last thread then the
963 * iterator will be moved to a point just beyond that last thread,
964 * (where notmuch_threads_valid will return FALSE and
965 * notmuch_threads_get will return NULL).
967 * See the documentation of notmuch_query_search_threads for example
968 * code showing how to iterate over a notmuch_threads_t object.
971 notmuch_threads_move_to_next (notmuch_threads_t *threads);
974 * Destroy a notmuch_threads_t object.
976 * It's not strictly necessary to call this function. All memory from
977 * the notmuch_threads_t object will be reclaimed when the
978 * containing query object is destroyed.
981 notmuch_threads_destroy (notmuch_threads_t *threads);
984 * Return the number of messages matching a search.
986 * This function performs a search and returns the number of matching
991 * NOTMUCH_STATUS_SUCCESS: query completed successfully.
993 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: a Xapian exception occured. The
994 * value of *count is not defined.
996 * @since libnotmuch 4.3 (notmuch 0.21)
999 notmuch_query_count_messages_st (notmuch_query_t *query, unsigned int *count);
1002 * like notmuch_query_count_messages_st, but without a status return.
1004 * May return 0 in the case of errors.
1006 * @deprecated Deprecated since libnotmuch 4.3 (notmuch 0.21). Please
1007 * use notmuch_query_count_messages_st instead.
1009 NOTMUCH_DEPRECATED(4,3)
1011 notmuch_query_count_messages (notmuch_query_t *query);
1014 * Return the number of threads matching a search.
1016 * This function performs a search and returns the number of unique thread IDs
1017 * in the matching messages. This is the same as number of threads matching a
1020 * Note that this is a significantly heavier operation than
1021 * notmuch_query_count_messages{_st}().
1025 * NOTMUCH_STATUS_OUT_OF_MEMORY: Memory allocation failed. The value
1026 * of *count is not defined
1028 * NOTMUCH_STATUS_SUCCESS: query completed successfully.
1030 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: a Xapian exception occured. The
1031 * value of *count is not defined.
1033 * @since libnotmuch 4.3 (notmuch 0.21)
1036 notmuch_query_count_threads_st (notmuch_query_t *query, unsigned *count);
1039 * like notmuch_query_count_threads, but without a status return.
1041 * May return 0 in case of errors.
1043 * @deprecated Deprecated as of libnotmuch 4.3 (notmuch 0.21). Please
1044 * use notmuch_query_count_threads_st instead.
1046 NOTMUCH_DEPRECATED(4,3)
1048 notmuch_query_count_threads (notmuch_query_t *query);
1051 * Get the thread ID of 'thread'.
1053 * The returned string belongs to 'thread' and as such, should not be
1054 * modified by the caller and will only be valid for as long as the
1055 * thread is valid, (which is until notmuch_thread_destroy or until
1056 * the query from which it derived is destroyed).
1059 notmuch_thread_get_thread_id (notmuch_thread_t *thread);
1062 * Get the total number of messages in 'thread'.
1064 * This count consists of all messages in the database belonging to
1065 * this thread. Contrast with notmuch_thread_get_matched_messages() .
1068 notmuch_thread_get_total_messages (notmuch_thread_t *thread);
1071 * Get a notmuch_messages_t iterator for the top-level messages in
1072 * 'thread' in oldest-first order.
1074 * This iterator will not necessarily iterate over all of the messages
1075 * in the thread. It will only iterate over the messages in the thread
1076 * which are not replies to other messages in the thread.
1078 * The returned list will be destroyed when the thread is destroyed.
1080 notmuch_messages_t *
1081 notmuch_thread_get_toplevel_messages (notmuch_thread_t *thread);
1084 * Get a notmuch_thread_t iterator for all messages in 'thread' in
1085 * oldest-first order.
1087 * The returned list will be destroyed when the thread is destroyed.
1089 notmuch_messages_t *
1090 notmuch_thread_get_messages (notmuch_thread_t *thread);
1093 * Get the number of messages in 'thread' that matched the search.
1095 * This count includes only the messages in this thread that were
1096 * matched by the search from which the thread was created and were
1097 * not excluded by any exclude tags passed in with the query (see
1098 * notmuch_query_add_tag_exclude). Contrast with
1099 * notmuch_thread_get_total_messages() .
1102 notmuch_thread_get_matched_messages (notmuch_thread_t *thread);
1105 * Get the authors of 'thread' as a UTF-8 string.
1107 * The returned string is a comma-separated list of the names of the
1108 * authors of mail messages in the query results that belong to this
1111 * The string contains authors of messages matching the query first, then
1112 * non-matched authors (with the two groups separated by '|'). Within
1113 * each group, authors are ordered by date.
1115 * The returned string belongs to 'thread' and as such, should not be
1116 * modified by the caller and will only be valid for as long as the
1117 * thread is valid, (which is until notmuch_thread_destroy or until
1118 * the query from which it derived is destroyed).
1121 notmuch_thread_get_authors (notmuch_thread_t *thread);
1124 * Get the subject of 'thread' as a UTF-8 string.
1126 * The subject is taken from the first message (according to the query
1127 * order---see notmuch_query_set_sort) in the query results that
1128 * belongs to this thread.
1130 * The returned string belongs to 'thread' and as such, should not be
1131 * modified by the caller and will only be valid for as long as the
1132 * thread is valid, (which is until notmuch_thread_destroy or until
1133 * the query from which it derived is destroyed).
1136 notmuch_thread_get_subject (notmuch_thread_t *thread);
1139 * Get the date of the oldest message in 'thread' as a time_t value.
1142 notmuch_thread_get_oldest_date (notmuch_thread_t *thread);
1145 * Get the date of the newest message in 'thread' as a time_t value.
1148 notmuch_thread_get_newest_date (notmuch_thread_t *thread);
1151 * Get the tags for 'thread', returning a notmuch_tags_t object which
1152 * can be used to iterate over all tags.
1154 * Note: In the Notmuch database, tags are stored on individual
1155 * messages, not on threads. So the tags returned here will be all
1156 * tags of the messages which matched the search and which belong to
1159 * The tags object is owned by the thread and as such, will only be
1160 * valid for as long as the thread is valid, (for example, until
1161 * notmuch_thread_destroy or until the query from which it derived is
1164 * Typical usage might be:
1166 * notmuch_thread_t *thread;
1167 * notmuch_tags_t *tags;
1170 * thread = notmuch_threads_get (threads);
1172 * for (tags = notmuch_thread_get_tags (thread);
1173 * notmuch_tags_valid (tags);
1174 * notmuch_tags_move_to_next (tags))
1176 * tag = notmuch_tags_get (tags);
1180 * notmuch_thread_destroy (thread);
1182 * Note that there's no explicit destructor needed for the
1183 * notmuch_tags_t object. (For consistency, we do provide a
1184 * notmuch_tags_destroy function, but there's no good reason to call
1185 * it if the message is about to be destroyed).
1188 notmuch_thread_get_tags (notmuch_thread_t *thread);
1191 * Destroy a notmuch_thread_t object.
1194 notmuch_thread_destroy (notmuch_thread_t *thread);
1197 * Is the given 'messages' iterator pointing at a valid message.
1199 * When this function returns TRUE, notmuch_messages_get will return a
1200 * valid object. Whereas when this function returns FALSE,
1201 * notmuch_messages_get will return NULL.
1203 * See the documentation of notmuch_query_search_messages for example
1204 * code showing how to iterate over a notmuch_messages_t object.
1207 notmuch_messages_valid (notmuch_messages_t *messages);
1210 * Get the current message from 'messages' as a notmuch_message_t.
1212 * Note: The returned message belongs to 'messages' and has a lifetime
1213 * identical to it (and the query to which it belongs).
1215 * See the documentation of notmuch_query_search_messages for example
1216 * code showing how to iterate over a notmuch_messages_t object.
1218 * If an out-of-memory situation occurs, this function will return
1222 notmuch_messages_get (notmuch_messages_t *messages);
1225 * Move the 'messages' iterator to the next message.
1227 * If 'messages' is already pointing at the last message then the
1228 * iterator will be moved to a point just beyond that last message,
1229 * (where notmuch_messages_valid will return FALSE and
1230 * notmuch_messages_get will return NULL).
1232 * See the documentation of notmuch_query_search_messages for example
1233 * code showing how to iterate over a notmuch_messages_t object.
1236 notmuch_messages_move_to_next (notmuch_messages_t *messages);
1239 * Destroy a notmuch_messages_t object.
1241 * It's not strictly necessary to call this function. All memory from
1242 * the notmuch_messages_t object will be reclaimed when the containing
1243 * query object is destroyed.
1246 notmuch_messages_destroy (notmuch_messages_t *messages);
1249 * Return a list of tags from all messages.
1251 * The resulting list is guaranteed not to contain duplicated tags.
1253 * WARNING: You can no longer iterate over messages after calling this
1254 * function, because the iterator will point at the end of the list.
1255 * We do not have a function to reset the iterator yet and the only
1256 * way how you can iterate over the list again is to recreate the
1259 * The function returns NULL on error.
1262 notmuch_messages_collect_tags (notmuch_messages_t *messages);
1265 * Get the message ID of 'message'.
1267 * The returned string belongs to 'message' and as such, should not be
1268 * modified by the caller and will only be valid for as long as the
1269 * message is valid, (which is until the query from which it derived
1272 * This function will not return NULL since Notmuch ensures that every
1273 * message has a unique message ID, (Notmuch will generate an ID for a
1274 * message if the original file does not contain one).
1277 notmuch_message_get_message_id (notmuch_message_t *message);
1280 * Get the thread ID of 'message'.
1282 * The returned string belongs to 'message' and as such, should not be
1283 * modified by the caller and will only be valid for as long as the
1284 * message is valid, (for example, until the user calls
1285 * notmuch_message_destroy on 'message' or until a query from which it
1286 * derived is destroyed).
1288 * This function will not return NULL since Notmuch ensures that every
1289 * message belongs to a single thread.
1292 notmuch_message_get_thread_id (notmuch_message_t *message);
1295 * Get a notmuch_messages_t iterator for all of the replies to
1298 * Note: This call only makes sense if 'message' was ultimately
1299 * obtained from a notmuch_thread_t object, (such as by coming
1300 * directly from the result of calling notmuch_thread_get_
1301 * toplevel_messages or by any number of subsequent
1302 * calls to notmuch_message_get_replies).
1304 * If 'message' was obtained through some non-thread means, (such as
1305 * by a call to notmuch_query_search_messages), then this function
1308 * If there are no replies to 'message', this function will return
1309 * NULL. (Note that notmuch_messages_valid will accept that NULL
1310 * value as legitimate, and simply return FALSE for it.)
1312 notmuch_messages_t *
1313 notmuch_message_get_replies (notmuch_message_t *message);
1316 * Get a filename for the email corresponding to 'message'.
1318 * The returned filename is an absolute filename, (the initial
1319 * component will match notmuch_database_get_path() ).
1321 * The returned string belongs to the message so should not be
1322 * modified or freed by the caller (nor should it be referenced after
1323 * the message is destroyed).
1325 * Note: If this message corresponds to multiple files in the mail
1326 * store, (that is, multiple files contain identical message IDs),
1327 * this function will arbitrarily return a single one of those
1328 * filenames. See notmuch_message_get_filenames for returning the
1329 * complete list of filenames.
1332 notmuch_message_get_filename (notmuch_message_t *message);
1335 * Get all filenames for the email corresponding to 'message'.
1337 * Returns a notmuch_filenames_t iterator listing all the filenames
1338 * associated with 'message'. These files may not have identical
1339 * content, but each will have the identical Message-ID.
1341 * Each filename in the iterator is an absolute filename, (the initial
1342 * component will match notmuch_database_get_path() ).
1344 notmuch_filenames_t *
1345 notmuch_message_get_filenames (notmuch_message_t *message);
1350 typedef enum _notmuch_message_flag {
1351 NOTMUCH_MESSAGE_FLAG_MATCH,
1352 NOTMUCH_MESSAGE_FLAG_EXCLUDED,
1354 /* This message is a "ghost message", meaning it has no filenames
1355 * or content, but we know it exists because it was referenced by
1356 * some other message. A ghost message has only a message ID and
1359 NOTMUCH_MESSAGE_FLAG_GHOST,
1360 } notmuch_message_flag_t;
1363 * Get a value of a flag for the email corresponding to 'message'.
1366 notmuch_message_get_flag (notmuch_message_t *message,
1367 notmuch_message_flag_t flag);
1370 * Set a value of a flag for the email corresponding to 'message'.
1373 notmuch_message_set_flag (notmuch_message_t *message,
1374 notmuch_message_flag_t flag, notmuch_bool_t value);
1377 * Get the date of 'message' as a time_t value.
1379 * For the original textual representation of the Date header from the
1380 * message call notmuch_message_get_header() with a header value of
1384 notmuch_message_get_date (notmuch_message_t *message);
1387 * Get the value of the specified header from 'message' as a UTF-8 string.
1389 * Common headers are stored in the database when the message is
1390 * indexed and will be returned from the database. Other headers will
1391 * be read from the actual message file.
1393 * The header name is case insensitive.
1395 * The returned string belongs to the message so should not be
1396 * modified or freed by the caller (nor should it be referenced after
1397 * the message is destroyed).
1399 * Returns an empty string ("") if the message does not contain a
1400 * header line matching 'header'. Returns NULL if any error occurs.
1403 notmuch_message_get_header (notmuch_message_t *message, const char *header);
1406 * Get the tags for 'message', returning a notmuch_tags_t object which
1407 * can be used to iterate over all tags.
1409 * The tags object is owned by the message and as such, will only be
1410 * valid for as long as the message is valid, (which is until the
1411 * query from which it derived is destroyed).
1413 * Typical usage might be:
1415 * notmuch_message_t *message;
1416 * notmuch_tags_t *tags;
1419 * message = notmuch_database_find_message (database, message_id);
1421 * for (tags = notmuch_message_get_tags (message);
1422 * notmuch_tags_valid (tags);
1423 * notmuch_tags_move_to_next (tags))
1425 * tag = notmuch_tags_get (tags);
1429 * notmuch_message_destroy (message);
1431 * Note that there's no explicit destructor needed for the
1432 * notmuch_tags_t object. (For consistency, we do provide a
1433 * notmuch_tags_destroy function, but there's no good reason to call
1434 * it if the message is about to be destroyed).
1437 notmuch_message_get_tags (notmuch_message_t *message);
1440 * The longest possible tag value.
1442 #define NOTMUCH_TAG_MAX 200
1445 * Add a tag to the given message.
1449 * NOTMUCH_STATUS_SUCCESS: Tag successfully added to message
1451 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
1453 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
1454 * (exceeds NOTMUCH_TAG_MAX)
1456 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1457 * mode so message cannot be modified.
1460 notmuch_message_add_tag (notmuch_message_t *message, const char *tag);
1463 * Remove a tag from the given message.
1467 * NOTMUCH_STATUS_SUCCESS: Tag successfully removed from message
1469 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
1471 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
1472 * (exceeds NOTMUCH_TAG_MAX)
1474 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1475 * mode so message cannot be modified.
1478 notmuch_message_remove_tag (notmuch_message_t *message, const char *tag);
1481 * Remove all tags from the given message.
1483 * See notmuch_message_freeze for an example showing how to safely
1484 * replace tag values.
1486 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1487 * mode so message cannot be modified.
1490 notmuch_message_remove_all_tags (notmuch_message_t *message);
1493 * Add/remove tags according to maildir flags in the message filename(s).
1495 * This function examines the filenames of 'message' for maildir
1496 * flags, and adds or removes tags on 'message' as follows when these
1497 * flags are present:
1499 * Flag Action if present
1500 * ---- -----------------
1501 * 'D' Adds the "draft" tag to the message
1502 * 'F' Adds the "flagged" tag to the message
1503 * 'P' Adds the "passed" tag to the message
1504 * 'R' Adds the "replied" tag to the message
1505 * 'S' Removes the "unread" tag from the message
1507 * For each flag that is not present, the opposite action (add/remove)
1508 * is performed for the corresponding tags.
1510 * Flags are identified as trailing components of the filename after a
1511 * sequence of ":2,".
1513 * If there are multiple filenames associated with this message, the
1514 * flag is considered present if it appears in one or more
1515 * filenames. (That is, the flags from the multiple filenames are
1516 * combined with the logical OR operator.)
1518 * A client can ensure that notmuch database tags remain synchronized
1519 * with maildir flags by calling this function after each call to
1520 * notmuch_database_add_message. See also
1521 * notmuch_message_tags_to_maildir_flags for synchronizing tag changes
1522 * back to maildir flags.
1525 notmuch_message_maildir_flags_to_tags (notmuch_message_t *message);
1528 * Rename message filename(s) to encode tags as maildir flags.
1530 * Specifically, for each filename corresponding to this message:
1532 * If the filename is not in a maildir directory, do nothing. (A
1533 * maildir directory is determined as a directory named "new" or
1534 * "cur".) Similarly, if the filename has invalid maildir info,
1535 * (repeated or outof-ASCII-order flag characters after ":2,"), then
1538 * If the filename is in a maildir directory, rename the file so that
1539 * its filename ends with the sequence ":2," followed by zero or more
1540 * of the following single-character flags (in ASCII order):
1542 * 'D' iff the message has the "draft" tag
1543 * 'F' iff the message has the "flagged" tag
1544 * 'P' iff the message has the "passed" tag
1545 * 'R' iff the message has the "replied" tag
1546 * 'S' iff the message does not have the "unread" tag
1548 * Any existing flags unmentioned in the list above will be preserved
1551 * Also, if this filename is in a directory named "new", rename it to
1552 * be within the neighboring directory named "cur".
1554 * A client can ensure that maildir filename flags remain synchronized
1555 * with notmuch database tags by calling this function after changing
1556 * tags, (after calls to notmuch_message_add_tag,
1557 * notmuch_message_remove_tag, or notmuch_message_freeze/
1558 * notmuch_message_thaw). See also notmuch_message_maildir_flags_to_tags
1559 * for synchronizing maildir flag changes back to tags.
1562 notmuch_message_tags_to_maildir_flags (notmuch_message_t *message);
1565 * Freeze the current state of 'message' within the database.
1567 * This means that changes to the message state, (via
1568 * notmuch_message_add_tag, notmuch_message_remove_tag, and
1569 * notmuch_message_remove_all_tags), will not be committed to the
1570 * database until the message is thawed with notmuch_message_thaw.
1572 * Multiple calls to freeze/thaw are valid and these calls will
1573 * "stack". That is there must be as many calls to thaw as to freeze
1574 * before a message is actually thawed.
1576 * The ability to do freeze/thaw allows for safe transactions to
1577 * change tag values. For example, explicitly setting a message to
1578 * have a given set of tags might look like this:
1580 * notmuch_message_freeze (message);
1582 * notmuch_message_remove_all_tags (message);
1584 * for (i = 0; i < NUM_TAGS; i++)
1585 * notmuch_message_add_tag (message, tags[i]);
1587 * notmuch_message_thaw (message);
1589 * With freeze/thaw used like this, the message in the database is
1590 * guaranteed to have either the full set of original tag values, or
1591 * the full set of new tag values, but nothing in between.
1593 * Imagine the example above without freeze/thaw and the operation
1594 * somehow getting interrupted. This could result in the message being
1595 * left with no tags if the interruption happened after
1596 * notmuch_message_remove_all_tags but before notmuch_message_add_tag.
1600 * NOTMUCH_STATUS_SUCCESS: Message successfully frozen.
1602 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1603 * mode so message cannot be modified.
1606 notmuch_message_freeze (notmuch_message_t *message);
1609 * Thaw the current 'message', synchronizing any changes that may have
1610 * occurred while 'message' was frozen into the notmuch database.
1612 * See notmuch_message_freeze for an example of how to use this
1613 * function to safely provide tag changes.
1615 * Multiple calls to freeze/thaw are valid and these calls with
1616 * "stack". That is there must be as many calls to thaw as to freeze
1617 * before a message is actually thawed.
1621 * NOTMUCH_STATUS_SUCCESS: Message successfully thawed, (or at least
1622 * its frozen count has successfully been reduced by 1).
1624 * NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW: An attempt was made to thaw
1625 * an unfrozen message. That is, there have been an unbalanced
1626 * number of calls to notmuch_message_freeze and
1627 * notmuch_message_thaw.
1630 notmuch_message_thaw (notmuch_message_t *message);
1633 * Destroy a notmuch_message_t object.
1635 * It can be useful to call this function in the case of a single
1636 * query object with many messages in the result, (such as iterating
1637 * over the entire database). Otherwise, it's fine to never call this
1638 * function and there will still be no memory leaks. (The memory from
1639 * the messages get reclaimed when the containing query is destroyed.)
1642 notmuch_message_destroy (notmuch_message_t *message);
1645 * Is the given 'tags' iterator pointing at a valid tag.
1647 * When this function returns TRUE, notmuch_tags_get will return a
1648 * valid string. Whereas when this function returns FALSE,
1649 * notmuch_tags_get will return NULL.
1651 * See the documentation of notmuch_message_get_tags for example code
1652 * showing how to iterate over a notmuch_tags_t object.
1655 notmuch_tags_valid (notmuch_tags_t *tags);
1658 * Get the current tag from 'tags' as a string.
1660 * Note: The returned string belongs to 'tags' and has a lifetime
1661 * identical to it (and the query to which it ultimately belongs).
1663 * See the documentation of notmuch_message_get_tags for example code
1664 * showing how to iterate over a notmuch_tags_t object.
1667 notmuch_tags_get (notmuch_tags_t *tags);
1670 * Move the 'tags' iterator to the next tag.
1672 * If 'tags' is already pointing at the last tag then the iterator
1673 * will be moved to a point just beyond that last tag, (where
1674 * notmuch_tags_valid will return FALSE and notmuch_tags_get will
1677 * See the documentation of notmuch_message_get_tags for example code
1678 * showing how to iterate over a notmuch_tags_t object.
1681 notmuch_tags_move_to_next (notmuch_tags_t *tags);
1684 * Destroy a notmuch_tags_t object.
1686 * It's not strictly necessary to call this function. All memory from
1687 * the notmuch_tags_t object will be reclaimed when the containing
1688 * message or query objects are destroyed.
1691 notmuch_tags_destroy (notmuch_tags_t *tags);
1694 * Store an mtime within the database for 'directory'.
1696 * The 'directory' should be an object retrieved from the database
1697 * with notmuch_database_get_directory for a particular path.
1699 * The intention is for the caller to use the mtime to allow efficient
1700 * identification of new messages to be added to the database. The
1701 * recommended usage is as follows:
1703 * o Read the mtime of a directory from the filesystem
1705 * o Call add_message for all mail files in the directory
1707 * o Call notmuch_directory_set_mtime with the mtime read from the
1710 * Then, when wanting to check for updates to the directory in the
1711 * future, the client can call notmuch_directory_get_mtime and know
1712 * that it only needs to add files if the mtime of the directory and
1713 * files are newer than the stored timestamp.
1715 * Note: The notmuch_directory_get_mtime function does not allow the
1716 * caller to distinguish a timestamp of 0 from a non-existent
1717 * timestamp. So don't store a timestamp of 0 unless you are
1718 * comfortable with that.
1722 * NOTMUCH_STATUS_SUCCESS: mtime successfully stored in database.
1724 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception
1725 * occurred, mtime not stored.
1727 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1728 * mode so directory mtime cannot be modified.
1731 notmuch_directory_set_mtime (notmuch_directory_t *directory,
1735 * Get the mtime of a directory, (as previously stored with
1736 * notmuch_directory_set_mtime).
1738 * Returns 0 if no mtime has previously been stored for this
1742 notmuch_directory_get_mtime (notmuch_directory_t *directory);
1745 * Get a notmuch_filenames_t iterator listing all the filenames of
1746 * messages in the database within the given directory.
1748 * The returned filenames will be the basename-entries only (not
1751 notmuch_filenames_t *
1752 notmuch_directory_get_child_files (notmuch_directory_t *directory);
1755 * Get a notmuch_filenames_t iterator listing all the filenames of
1756 * sub-directories in the database within the given directory.
1758 * The returned filenames will be the basename-entries only (not
1761 notmuch_filenames_t *
1762 notmuch_directory_get_child_directories (notmuch_directory_t *directory);
1765 * Delete directory document from the database, and destroy the
1766 * notmuch_directory_t object. Assumes any child directories and files
1767 * have been deleted by the caller.
1769 * @since libnotmuch 4.3 (notmuch 0.21)
1772 notmuch_directory_delete (notmuch_directory_t *directory);
1775 * Destroy a notmuch_directory_t object.
1778 notmuch_directory_destroy (notmuch_directory_t *directory);
1781 * Is the given 'filenames' iterator pointing at a valid filename.
1783 * When this function returns TRUE, notmuch_filenames_get will return
1784 * a valid string. Whereas when this function returns FALSE,
1785 * notmuch_filenames_get will return NULL.
1787 * It is acceptable to pass NULL for 'filenames', in which case this
1788 * function will always return FALSE.
1791 notmuch_filenames_valid (notmuch_filenames_t *filenames);
1794 * Get the current filename from 'filenames' as a string.
1796 * Note: The returned string belongs to 'filenames' and has a lifetime
1797 * identical to it (and the directory to which it ultimately belongs).
1799 * It is acceptable to pass NULL for 'filenames', in which case this
1800 * function will always return NULL.
1803 notmuch_filenames_get (notmuch_filenames_t *filenames);
1806 * Move the 'filenames' iterator to the next filename.
1808 * If 'filenames' is already pointing at the last filename then the
1809 * iterator will be moved to a point just beyond that last filename,
1810 * (where notmuch_filenames_valid will return FALSE and
1811 * notmuch_filenames_get will return NULL).
1813 * It is acceptable to pass NULL for 'filenames', in which case this
1814 * function will do nothing.
1817 notmuch_filenames_move_to_next (notmuch_filenames_t *filenames);
1820 * Destroy a notmuch_filenames_t object.
1822 * It's not strictly necessary to call this function. All memory from
1823 * the notmuch_filenames_t object will be reclaimed when the
1824 * containing directory object is destroyed.
1826 * It is acceptable to pass NULL for 'filenames', in which case this
1827 * function will do nothing.
1830 notmuch_filenames_destroy (notmuch_filenames_t *filenames);