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>
25 # define NOTMUCH_BEGIN_DECLS extern "C" {
26 # define NOTMUCH_END_DECLS }
28 # define NOTMUCH_BEGIN_DECLS
29 # define NOTMUCH_END_DECLS
44 typedef int notmuch_bool_t;
46 /* Status codes used for the return values of most functions.
48 * A zero value (NOTMUCH_STATUS_SUCCESS) indicates that the function
49 * completed without error. Any other value indicates an error as
52 * NOTMUCH_STATUS_SUCCESS: No error occurred.
54 * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory
56 * XXX: We don't really want to expose this lame XAPIAN_EXCEPTION
57 * value. Instead we should map to things like DATABASE_LOCKED or
60 * NOTMUCH_STATUS_READONLY_DATABASE: An attempt was made to write to a
61 * database opened in read-only mode.
63 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred
65 * NOTMUCH_STATUS_FILE_ERROR: An error occurred trying to read or
66 * write to a file (this could be file not found, permission
69 * NOTMUCH_STATUS_FILE_NOT_EMAIL: A file was presented that doesn't
70 * appear to be an email message.
72 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: A file contains a message ID
73 * that is identical to a message already in the database.
75 * NOTMUCH_STATUS_NULL_POINTER: The user erroneously passed a NULL
76 * pointer to a notmuch function.
78 * NOTMUCH_STATUS_TAG_TOO_LONG: A tag value is too long (exceeds
81 * NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW: The notmuch_message_thaw
82 * function has been called more times than notmuch_message_freeze.
86 * NOTMUCH_STATUS_LAST_STATUS: Not an actual status value. Just a way
87 * to find out how many valid status values there are.
89 typedef enum _notmuch_status {
90 NOTMUCH_STATUS_SUCCESS = 0,
91 NOTMUCH_STATUS_OUT_OF_MEMORY,
92 NOTMUCH_STATUS_READONLY_DATABASE,
93 NOTMUCH_STATUS_XAPIAN_EXCEPTION,
94 NOTMUCH_STATUS_FILE_ERROR,
95 NOTMUCH_STATUS_FILE_NOT_EMAIL,
96 NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID,
97 NOTMUCH_STATUS_NULL_POINTER,
98 NOTMUCH_STATUS_TAG_TOO_LONG,
99 NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW,
101 NOTMUCH_STATUS_LAST_STATUS
104 /* Get a string representation of a notmuch_status_t value.
106 * The result is readonly.
109 notmuch_status_to_string (notmuch_status_t status);
111 /* Various opaque data types. For each notmuch_<foo>_t see the various
112 * notmuch_<foo> functions below. */
113 typedef struct _notmuch_database notmuch_database_t;
114 typedef struct _notmuch_query notmuch_query_t;
115 typedef struct _notmuch_threads notmuch_threads_t;
116 typedef struct _notmuch_thread notmuch_thread_t;
117 typedef struct _notmuch_messages notmuch_messages_t;
118 typedef struct _notmuch_message notmuch_message_t;
119 typedef struct _notmuch_tags notmuch_tags_t;
120 typedef struct _notmuch_directory notmuch_directory_t;
121 typedef struct _notmuch_filenames notmuch_filenames_t;
123 /* Create a new, empty notmuch database located at 'path'.
125 * The path should be a top-level directory to a collection of
126 * plain-text email messages (one message per file). This call will
127 * create a new ".notmuch" directory within 'path' where notmuch will
130 * After a successful call to notmuch_database_create, the returned
131 * database will be open so the caller should call
132 * notmuch_database_close when finished with it.
134 * The database will not yet have any data in it
135 * (notmuch_database_create itself is a very cheap function). Messages
136 * contained within 'path' can be added to the database by calling
137 * notmuch_database_add_message.
139 * In case of any failure, this function returns NULL, (after printing
140 * an error message on stderr).
143 notmuch_database_create (const char *path);
146 NOTMUCH_DATABASE_MODE_READ_ONLY = 0,
147 NOTMUCH_DATABASE_MODE_READ_WRITE
148 } notmuch_database_mode_t;
150 /* XXX: I think I'd like this to take an extra argument of
151 * notmuch_status_t* for returning a status value on failure. */
153 /* Open an existing notmuch database located at 'path'.
155 * The database should have been created at some time in the past,
156 * (not necessarily by this process), by calling
157 * notmuch_database_create with 'path'. By default the database should be
158 * opened for reading only. In order to write to the database you need to
159 * pass the NOTMUCH_DATABASE_MODE_WRITABLE mode.
161 * An existing notmuch database can be identified by the presence of a
162 * directory named ".notmuch" below 'path'.
164 * The caller should call notmuch_database_close when finished with
167 * In case of any failure, this function returns NULL, (after printing
168 * an error message on stderr).
171 notmuch_database_open (const char *path,
172 notmuch_database_mode_t mode);
174 /* Close the given notmuch database, freeing all associated
175 * resources. See notmuch_database_open. */
177 notmuch_database_close (notmuch_database_t *database);
179 /* Return the database path of the given database.
181 * The return value is a string owned by notmuch so should not be
182 * modified nor freed by the caller. */
184 notmuch_database_get_path (notmuch_database_t *database);
186 /* Retrieve a directory object from the database for 'path'.
188 * Here, 'path' should be a path relative to the path of 'database'
189 * (see notmuch_database_get_path), or else should be an absolute path
190 * with initial components that match the path of 'database'.
192 * Note: The resulting notmuch_directory_t object will represent the
193 * state as it currently exists in the database, (and will not reflect
194 * subsequent changes).
196 notmuch_directory_t *
197 notmuch_database_get_directory (notmuch_database_t *database,
200 /* Add a new message to the given notmuch database.
202 * Here,'filename' should be a path relative to the path of
203 * 'database' (see notmuch_database_get_path), or else should be an
204 * absolute filename with initial components that match the path of
207 * The file should be a single mail message (not a multi-message mbox)
208 * that is expected to remain at its current location, (since the
209 * notmuch database will reference the filename, and will not copy the
210 * entire contents of the file.
212 * If 'message' is not NULL, then, on successful return '*message'
213 * will be initialized to a message object that can be used for things
214 * such as adding tags to the just-added message. The user should call
215 * notmuch_message_destroy when done with the message. On any failure
216 * '*message' will be set to NULL.
220 * NOTMUCH_STATUS_SUCCESS: Message successfully added to database.
222 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: Message has the same message
223 * ID as another message already in the database. The new filename
224 * was successfully added to the message in the database.
226 * NOTMUCH_STATUS_FILE_ERROR: an error occurred trying to open the
227 * file, (such as permission denied, or file not found,
228 * etc.). Nothing added to the database.
230 * NOTMUCH_STATUS_FILE_NOT_EMAIL: the contents of filename don't look
231 * like an email message. Nothing added to the database.
234 notmuch_database_add_message (notmuch_database_t *database,
235 const char *filename,
236 notmuch_message_t **message);
238 /* Remove a message from the given notmuch database.
240 * Note that only this particular filename association is removed from
241 * the database. If the same message (as determined by the message ID)
242 * is still available via other filenames, then the message will
243 * persist in the database for those filenames. When the last filename
244 * is removed for a particular message, the database content for that
245 * message will be entirely removed.
249 * NOTMUCH_STATUS_SUCCESS: The last filename was removed and the
250 * message was removed from the database.
252 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: This filename was removed but
253 * the message persists in the database with at least one other
257 notmuch_database_remove_message (notmuch_database_t *database,
258 const char *filename);
260 /* Find a message with the given message_id.
262 * If the database contains a message with the given message_id, then
263 * a new notmuch_message_t object is returned. The caller should call
264 * notmuch_message_destroy when done with the message.
266 * If no message is found with the given message_id or if an
267 * out-of-memory situation occurs, this function returns NULL.
270 notmuch_database_find_message (notmuch_database_t *database,
271 const char *message_id);
273 /* Return a list of all tags found in the database.
275 * This function creates a list of all tags found in the database. The
276 * resulting list contains all tags from all messages found in the database.
278 * On error this function returns NULL.
281 notmuch_database_get_all_tags (notmuch_database_t *db);
283 /* Create a new query for 'database'.
285 * Here, 'database' should be an open database, (see
286 * notmuch_database_open and notmuch_database_create).
288 * For the query string, we'll document the syntax here more
289 * completely in the future, but it's likely to be a specialized
290 * version of the general Xapian query syntax:
292 * http://xapian.org/docs/queryparser.html
294 * As a special case, passing a length-zero string, (that is ""), will
295 * result in a query that returns all messages in the database.
297 * See notmuch_query_set_sort for controlling the order of results and
298 * notmuch_query_search to actually execute the query.
300 * User should call notmuch_query_destroy when finished with this
303 * Will return NULL if insufficient memory is available.
306 notmuch_query_create (notmuch_database_t *database,
307 const char *query_string);
309 /* Sort values for notmuch_query_set_sort */
311 NOTMUCH_SORT_OLDEST_FIRST,
312 NOTMUCH_SORT_NEWEST_FIRST,
313 NOTMUCH_SORT_MESSAGE_ID
316 /* Specify the sorting desired for this query. */
318 notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort);
320 /* Execute a query for threads, returning a notmuch_threads_t object
321 * which can be used to iterate over the results. The returned threads
322 * object is owned by the query and as such, will only be valid until
323 * notmuch_query_destroy.
325 * Typical usage might be:
327 * notmuch_query_t *query;
328 * notmuch_threads_t *threads;
329 * notmuch_thread_t *thread;
331 * query = notmuch_query_create (database, query_string);
333 * for (threads = notmuch_query_search_threads (query);
334 * notmuch_threads_has_more (threads);
335 * notmuch_threads_advance (threads))
337 * thread = notmuch_threads_get (threads);
339 * notmuch_thread_destroy (thread);
342 * notmuch_query_destroy (query);
344 * Note: If you are finished with a thread before its containing
345 * query, you can call notmuch_thread_destroy to clean up some memory
346 * sooner (as in the above example). Otherwise, if your thread objects
347 * are long-lived, then you don't need to call notmuch_thread_destroy
348 * and all the memory will still be reclaimed when the query is
351 * Note that there's no explicit destructor needed for the
352 * notmuch_threads_t object. (For consistency, we do provide a
353 * notmuch_threads_destroy function, but there's no good reason
354 * to call it if the query is about to be destroyed).
357 notmuch_query_search_threads (notmuch_query_t *query);
359 /* Execute a query for messages, returning a notmuch_messages_t object
360 * which can be used to iterate over the results. The returned
361 * messages object is owned by the query and as such, will only be
362 * valid until notmuch_query_destroy.
364 * Typical usage might be:
366 * notmuch_query_t *query;
367 * notmuch_messages_t *messages;
368 * notmuch_message_t *message;
370 * query = notmuch_query_create (database, query_string);
372 * for (messages = notmuch_query_search_messages (query);
373 * notmuch_messages_has_more (messages);
374 * notmuch_messages_advance (messages))
376 * message = notmuch_messages_get (messages);
378 * notmuch_message_destroy (message);
381 * notmuch_query_destroy (query);
383 * Note: If you are finished with a message before its containing
384 * query, you can call notmuch_message_destroy to clean up some memory
385 * sooner (as in the above example). Otherwise, if your message
386 * objects are long-lived, then you don't need to call
387 * notmuch_message_destroy and all the memory will still be reclaimed
388 * when the query is destroyed.
390 * Note that there's no explicit destructor needed for the
391 * notmuch_messages_t object. (For consistency, we do provide a
392 * notmuch_messages_destroy function, but there's no good
393 * reason to call it if the query is about to be destroyed).
396 notmuch_query_search_messages (notmuch_query_t *query);
398 /* Destroy a notmuch_query_t along with any associated resources.
400 * This will in turn destroy any notmuch_threads_t and
401 * notmuch_messages_t objects generated by this query, (and in
402 * turn any notmuch_thrad_t and notmuch_message_t objects generated
403 * from those results, etc.), if such objects haven't already been
407 notmuch_query_destroy (notmuch_query_t *query);
409 /* Does the given notmuch_threads_t object contain any more
412 * When this function returns TRUE, notmuch_threads_get will
413 * return a valid object. Whereas when this function returns FALSE,
414 * notmuch_threads_get will return NULL.
416 * See the documentation of notmuch_query_search_threads for example
417 * code showing how to iterate over a notmuch_threads_t object.
420 notmuch_threads_has_more (notmuch_threads_t *threads);
422 /* Get the current thread from 'threads' as a notmuch_thread_t.
424 * Note: The returned thread belongs to 'threads' and has a lifetime
425 * identical to it (and the query to which it belongs).
427 * See the documentation of notmuch_query_search_threads for example
428 * code showing how to iterate over a notmuch_threads_t object.
430 * If an out-of-memory situation occurs, this function will return
434 notmuch_threads_get (notmuch_threads_t *threads);
436 /* Advance the 'threads' iterator to the next thread.
438 * See the documentation of notmuch_query_search_threads for example
439 * code showing how to iterate over a notmuch_threads_t object.
442 notmuch_threads_advance (notmuch_threads_t *threads);
444 /* Destroy a notmuch_threads_t object.
446 * It's not strictly necessary to call this function. All memory from
447 * the notmuch_threads_t object will be reclaimed when the
448 * containg query object is destroyed.
451 notmuch_threads_destroy (notmuch_threads_t *threads);
453 /* Return an estimate of the number of messages matching a search
455 * This function performs a search and returns Xapian's best
456 * guess as to number of matching messages.
459 notmuch_query_count_messages (notmuch_query_t *query);
461 /* Get the thread ID of 'thread'.
463 * The returned string belongs to 'thread' and as such, should not be
464 * modified by the caller and will only be valid for as long as the
465 * thread is valid, (which is until notmuch_thread_destroy or until
466 * the query from which it derived is destroyed).
469 notmuch_thread_get_thread_id (notmuch_thread_t *thread);
471 /* Get the total number of messages in 'thread'.
473 * This count consists of all messages in the database belonging to
474 * this thread. Contrast with notmuch_thread_get_matched_messages() .
477 notmuch_thread_get_total_messages (notmuch_thread_t *thread);
479 /* Get a notmuch_messages_t iterator for the top-level messages in
482 * This iterator will not necessarily iterate over all of the messages
483 * in the thread. It will only iterate over the messages in the thread
484 * which are not replies to other messages in the thread.
486 * To iterate over all messages in the thread, the caller will need to
487 * iterate over the result of notmuch_message_get_replies for each
488 * top-level message (and do that recursively for the resulting
492 notmuch_thread_get_toplevel_messages (notmuch_thread_t *thread);
494 /* Get the number of messages in 'thread' that matched the search.
496 * This count includes only the messages in this thread that were
497 * matched by the search from which the thread was created. Contrast
498 * with notmuch_thread_get_total_messages() .
501 notmuch_thread_get_matched_messages (notmuch_thread_t *thread);
503 /* Get the authors of 'thread'
505 * The returned string is a comma-separated list of the names of the
506 * authors of mail messages in the query results that belong to this
509 * The returned string belongs to 'thread' and as such, should not be
510 * modified by the caller and will only be valid for as long as the
511 * thread is valid, (which is until notmuch_thread_destroy or until
512 * the query from which it derived is destroyed).
515 notmuch_thread_get_authors (notmuch_thread_t *thread);
517 /* Get the subject of 'thread'
519 * The subject is taken from the first message (according to the query
520 * order---see notmuch_query_set_sort) in the query results that
521 * belongs to this thread.
523 * The returned string belongs to 'thread' and as such, should not be
524 * modified by the caller and will only be valid for as long as the
525 * thread is valid, (which is until notmuch_thread_destroy or until
526 * the query from which it derived is destroyed).
529 notmuch_thread_get_subject (notmuch_thread_t *thread);
531 /* Get the date of the oldest message in 'thread' as a time_t value.
534 notmuch_thread_get_oldest_date (notmuch_thread_t *thread);
536 /* Get the date of the oldest message in 'thread' as a time_t value.
539 notmuch_thread_get_newest_date (notmuch_thread_t *thread);
541 /* Get the tags for 'thread', returning a notmuch_tags_t object which
542 * can be used to iterate over all tags.
544 * Note: In the Notmuch database, tags are stored on individual
545 * messages, not on threads. So the tags returned here will be all
546 * tags of the messages which matched the search and which belong to
549 * The tags object is owned by the thread and as such, will only be
550 * valid for as long as the thread is valid, (for example, until
551 * notmuch_thread_destroy or until the query from which it derived is
554 * Typical usage might be:
556 * notmuch_thread_t *thread;
557 * notmuch_tags_t *tags;
560 * thread = notmuch_threads_get (threads);
562 * for (tags = notmuch_thread_get_tags (thread);
563 * notmuch_tags_has_more (tags);
564 * notmuch_result_advance (tags))
566 * tag = notmuch_tags_get (tags);
570 * notmuch_thread_destroy (thread);
572 * Note that there's no explicit destructor needed for the
573 * notmuch_tags_t object. (For consistency, we do provide a
574 * notmuch_tags_destroy function, but there's no good reason to call
575 * it if the message is about to be destroyed).
578 notmuch_thread_get_tags (notmuch_thread_t *thread);
580 /* Destroy a notmuch_thread_t object. */
582 notmuch_thread_destroy (notmuch_thread_t *thread);
584 /* Does the given notmuch_messages_t object contain any more
587 * When this function returns TRUE, notmuch_messages_get will return a
588 * valid object. Whereas when this function returns FALSE,
589 * notmuch_messages_get will return NULL.
591 * See the documentation of notmuch_query_search_messages for example
592 * code showing how to iterate over a notmuch_messages_t object.
595 notmuch_messages_has_more (notmuch_messages_t *messages);
597 /* Get the current message from 'messages' as a notmuch_message_t.
599 * Note: The returned message belongs to 'messages' and has a lifetime
600 * identical to it (and the query to which it belongs).
602 * See the documentation of notmuch_query_search_messages for example
603 * code showing how to iterate over a notmuch_messages_t object.
605 * If an out-of-memory situation occurs, this function will return
609 notmuch_messages_get (notmuch_messages_t *messages);
611 /* Advance the 'messages' iterator to the next result.
613 * See the documentation of notmuch_query_search_messages for example
614 * code showing how to iterate over a notmuch_messages_t object.
617 notmuch_messages_advance (notmuch_messages_t *messages);
619 /* Destroy a notmuch_messages_t object.
621 * It's not strictly necessary to call this function. All memory from
622 * the notmuch_messages_t object will be reclaimed when the containing
623 * query object is destroyed.
626 notmuch_messages_destroy (notmuch_messages_t *messages);
628 /* Return a list of tags from all messages.
630 * The resulting list is guaranteed not to contain duplicated tags.
632 * WARNING: You can no longer iterate over messages after calling this
633 * function, because the iterator will point at the end of the list.
634 * We do not have a function to reset the iterator yet and the only
635 * way how you can iterate over the list again is to recreate the
638 * The function returns NULL on error.
641 notmuch_messages_collect_tags (notmuch_messages_t *messages);
643 /* Get the message ID of 'message'.
645 * The returned string belongs to 'message' and as such, should not be
646 * modified by the caller and will only be valid for as long as the
647 * message is valid, (which is until the query from which it derived
650 * This function will not return NULL since Notmuch ensures that every
651 * message has a unique message ID, (Notmuch will generate an ID for a
652 * message if the original file does not contain one).
655 notmuch_message_get_message_id (notmuch_message_t *message);
657 /* Get the thread ID of 'message'.
659 * The returned string belongs to 'message' and as such, should not be
660 * modified by the caller and will only be valid for as long as the
661 * message is valid, (for example, until the user calls
662 * notmuch_message_destroy on 'message' or until a query from which it
663 * derived is destroyed).
665 * This function will not return NULL since Notmuch ensures that every
666 * message belongs to a single thread.
669 notmuch_message_get_thread_id (notmuch_message_t *message);
671 /* Get a notmuch_messages_t iterator for all of the replies to
674 * Note: This call only makes sense if 'message' was ultimately
675 * obtained from a notmuch_thread_t object, (such as by coming
676 * directly from the result of calling notmuch_thread_get_
677 * toplevel_messages or by any number of subsequent
678 * calls to notmuch_message_get_replies).
680 * If 'message' was obtained through some non-thread means, (such as
681 * by a call to notmuch_query_search_messages), then this function
684 * If there are no replies to 'message', this function will return
685 * NULL. (Note that notmuch_messages_has_more will accept that NULL
686 * value as legitimate, and simply return FALSE for it.)
689 notmuch_message_get_replies (notmuch_message_t *message);
691 /* Get a filename for the email corresponding to 'message'.
693 * The returned filename is an absolute filename, (the initial
694 * component will match notmuch_database_get_path() ).
696 * The returned string belongs to the message so should not be
697 * modified or freed by the caller (nor should it be referenced after
698 * the message is destroyed).
700 * Note: If this message corresponds to multiple files in the mail
701 * store, (that is, multiple files contain identical message IDs),
702 * this function will arbitrarily return a single one of those
706 notmuch_message_get_filename (notmuch_message_t *message);
709 typedef enum _notmuch_message_flag {
710 NOTMUCH_MESSAGE_FLAG_MATCH,
711 } notmuch_message_flag_t;
713 /* Get a value of a flag for the email corresponding to 'message'. */
715 notmuch_message_get_flag (notmuch_message_t *message,
716 notmuch_message_flag_t flag);
718 /* Set a value of a flag for the email corresponding to 'message'. */
720 notmuch_message_set_flag (notmuch_message_t *message,
721 notmuch_message_flag_t flag, notmuch_bool_t value);
723 /* Get the date of 'message' as a time_t value.
725 * For the original textual representation of the Date header from the
726 * message call notmuch_message_get_header() with a header value of
729 notmuch_message_get_date (notmuch_message_t *message);
731 /* Get the value of the specified header from 'message'.
733 * The value will be read from the actual message file, not from the
734 * notmuch database. The header name is case insensitive.
736 * The returned string belongs to the message so should not be
737 * modified or freed by the caller (nor should it be referenced after
738 * the message is destroyed).
740 * Returns an empty string ("") if the message does not contain a
741 * header line matching 'header'. Returns NULL if any error occurs.
744 notmuch_message_get_header (notmuch_message_t *message, const char *header);
746 /* Get the tags for 'message', returning a notmuch_tags_t object which
747 * can be used to iterate over all tags.
749 * The tags object is owned by the message and as such, will only be
750 * valid for as long as the message is valid, (which is until the
751 * query from which it derived is destroyed).
753 * Typical usage might be:
755 * notmuch_message_t *message;
756 * notmuch_tags_t *tags;
759 * message = notmuch_database_find_message (database, message_id);
761 * for (tags = notmuch_message_get_tags (message);
762 * notmuch_tags_has_more (tags);
763 * notmuch_result_advance (tags))
765 * tag = notmuch_tags_get (tags);
769 * notmuch_message_destroy (message);
771 * Note that there's no explicit destructor needed for the
772 * notmuch_tags_t object. (For consistency, we do provide a
773 * notmuch_tags_destroy function, but there's no good reason to call
774 * it if the message is about to be destroyed).
777 notmuch_message_get_tags (notmuch_message_t *message);
779 /* The longest possible tag value. */
780 #define NOTMUCH_TAG_MAX 200
782 /* Add a tag to the given message.
786 * NOTMUCH_STATUS_SUCCESS: Tag successfully added to message
788 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
790 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
791 * (exceeds NOTMUCH_TAG_MAX)
794 notmuch_message_add_tag (notmuch_message_t *message, const char *tag);
796 /* Remove a tag from the given message.
800 * NOTMUCH_STATUS_SUCCESS: Tag successfully removed from message
802 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
804 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
805 * (exceeds NOTMUCH_TAG_MAX)
808 notmuch_message_remove_tag (notmuch_message_t *message, const char *tag);
810 /* Remove all tags from the given message.
812 * See notmuch_message_freeze for an example showing how to safely
813 * replace tag values.
816 notmuch_message_remove_all_tags (notmuch_message_t *message);
818 /* Freeze the current state of 'message' within the database.
820 * This means that changes to the message state, (via
821 * notmuch_message_add_tag, notmuch_message_remove_tag, and
822 * notmuch_message_remove_all_tags), will not be committed to the
823 * database until the message is thawed with notmuch_message_thaw.
825 * Multiple calls to freeze/thaw are valid and these calls with
826 * "stack". That is there must be as many calls to thaw as to freeze
827 * before a message is actually thawed.
829 * The ability to do freeze/thaw allows for safe transactions to
830 * change tag values. For example, explicitly setting a message to
831 * have a given set of tags might look like this:
833 * notmuch_message_freeze (message);
835 * notmuch_message_remove_all_tags (message);
837 * for (i = 0; i < NUM_TAGS; i++)
838 * notmuch_message_add_tag (message, tags[i]);
840 * notmuch_message_thaw (message);
842 * With freeze/thaw used like this, the message in the database is
843 * guaranteed to have either the full set of original tag value, or
844 * the full set of new tag values, but nothing in between.
846 * Imagine the example above without freeze/thaw and the operation
847 * somehow getting interrupted. This could result in the message being
848 * left with no tags if the interruption happened after
849 * notmuch_message_remove_all_tags but before notmuch_message_add_tag.
852 notmuch_message_freeze (notmuch_message_t *message);
854 /* Thaw the current 'message', synchronizing any changes that may have
855 * occurred while 'message' was frozen into the notmuch database.
857 * See notmuch_message_freeze for an example of how to use this
858 * function to safely provide tag changes.
860 * Multiple calls to freeze/thaw are valid and these calls with
861 * "stack". That is there must be as many calls to thaw as to freeze
862 * before a message is actually thawed.
866 * NOTMUCH_STATUS_SUCCESS: Message successfully thawed, (or at least
867 * its frozen count has successfully been reduced by 1).
869 * NOTMUCH_STATUS_UNBALANCE_FREEZE_THAW: An attempt was made to thaw
870 * an unfrozen message. That is, there have been an unbalanced
871 * number of calls to notmuch_message_freeze and
872 * notmuch_message_thaw.
875 notmuch_message_thaw (notmuch_message_t *message);
877 /* Destroy a notmuch_message_t object.
879 * It can be useful to call this function in the case of a single
880 * query object with many messages in the result, (such as iterating
881 * over the entire database). Otherwise, it's fine to never call this
882 * function and there will still be no memory leaks. (The memory from
883 * the messages get reclaimed when the containing query is destroyed.)
886 notmuch_message_destroy (notmuch_message_t *message);
888 /* Does the given notmuch_tags_t object contain any more tags.
890 * When this function returns TRUE, notmuch_tags_get will return a
891 * valid string. Whereas when this function returns FALSE,
892 * notmuch_tags_get will return NULL.
894 * See the documentation of notmuch_message_get_tags for example code
895 * showing how to iterate over a notmuch_tags_t object.
898 notmuch_tags_has_more (notmuch_tags_t *tags);
900 /* Get the current tag from 'tags' as a string.
902 * Note: The returned string belongs to 'tags' and has a lifetime
903 * identical to it (and the query to which it ultimately belongs).
905 * See the documentation of notmuch_message_get_tags for example code
906 * showing how to iterate over a notmuch_tags_t object.
909 notmuch_tags_get (notmuch_tags_t *tags);
911 /* Advance the 'tags' iterator to the next tag.
913 * See the documentation of notmuch_message_get_tags for example code
914 * showing how to iterate over a notmuch_tags_t object.
917 notmuch_tags_advance (notmuch_tags_t *tags);
919 /* Destroy a notmuch_tags_t object.
921 * It's not strictly necessary to call this function. All memory from
922 * the notmuch_tags_t object will be reclaimed when the containing
923 * message or query objects are destroyed.
926 notmuch_tags_destroy (notmuch_tags_t *tags);
928 /* Store an mtime within the database for 'directory'.
930 * The 'directory' should be an object retrieved from the database
931 * with notmuch_database_get_directory for a particular path.
933 * The intention is for the caller to use the mtime to allow efficient
934 * identification of new messages to be added to the database. The
935 * recommended usage is as follows:
937 * o Read the mtime of a directory from the filesystem
939 * o Call add_message for all mail files in the directory
941 * o Call notmuch_directory_set_mtime with the mtime read from the
944 * Then, when wanting to check for updates to the directory in the
945 * future, the client can call notmuch_directory_get_mtime and know
946 * that it only needs to add files if the mtime of the directory and
947 * files are newer than the stored timestamp.
949 * Note: The notmuch_directory_get_mtime function does not allow the
950 * caller to distinguish a timestamp of 0 from a non-existent
951 * timestamp. So don't store a timestamp of 0 unless you are
952 * comfortable with that.
956 * NOTMUCH_STATUS_SUCCESS: mtime successfully stored in database.
958 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception
959 * occurred, mtime not stored.
962 notmuch_directory_set_mtime (notmuch_directory_t *directory,
965 /* Get the mtime of a directory, (as previously stored with
966 * notmuch_directory_set_mtime).
968 * Returns 0 if not mtime has previously been stored for this
971 notmuch_directory_get_mtime (notmuch_directory_t *directory);
973 /* Get a notmuch_filenames_t iterator listing all the filenames of
974 * messages in the database within the given directory.
976 * The returned filenames will be the basename-entries only (not
977 * complete paths). */
978 notmuch_filenames_t *
979 notmuch_directory_get_child_files (notmuch_directory_t *directory);
981 /* Get a notmuch_filenams_t iterator listing all the filenames of
982 * sub-directories in the database within the given directory.
984 * The returned filenames will be the basename-entries only (not
985 * complete paths). */
986 notmuch_filenames_t *
987 notmuch_directory_get_child_directories (notmuch_directory_t *directory);
989 /* Destroy a notmuch_directory_t object. */
991 notmuch_directory_destroy (notmuch_directory_t *directory);
993 /* Does the given notmuch_filenames_t object contain any more
996 * When this function returns TRUE, notmuch_filenames_get will return
997 * a valid string. Whereas when this function returns FALSE,
998 * notmuch_filenames_get will return NULL.
1001 notmuch_filenames_has_more (notmuch_filenames_t *filenames);
1003 /* Get the current filename from 'filenames' as a string.
1005 * Note: The returned string belongs to 'filenames' and has a lifetime
1006 * identical to it (and the directory to which it ultimately belongs).
1009 notmuch_filenames_get (notmuch_filenames_t *filenames);
1011 /* Advance the 'filenames' iterator to the next filename.
1014 notmuch_filenames_advance (notmuch_filenames_t *filenames);
1016 /* Destroy a notmuch_filenames_t object.
1018 * It's not strictly necessary to call this function. All memory from
1019 * the notmuch_filenames_t object will be reclaimed when the
1020 * containing directory object is destroyed.
1023 notmuch_filenames_destroy (notmuch_filenames_t *filenames);