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_READ_ONLY_DATABASE: An attempt was made to write to
61 * a 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_READ_ONLY_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 /* Return the database format version of the given database. */
188 notmuch_database_get_version (notmuch_database_t *database);
190 /* Does this database need to be upgraded before writing to it?
192 * If this function returns TRUE then no functions that modify the
193 * database (notmuch_database_add_message, notmuch_message_add_tag,
194 * notmuch_directory_set_mtime, etc.) will work unless the function
195 * notmuch_database_upgrade is called successfully first. */
197 notmuch_database_needs_upgrade (notmuch_database_t *database);
199 /* Upgrade the current database.
201 * After opening a database in read-write mode, the client should
202 * check if an upgrade is needed (notmuch_database_needs_upgrade) and
203 * if so, upgrade with this function before making any modifications.
205 * The optional progress_notify callback can be used by the caller to
206 * provide progress indication to the user. If non-NULL it will be
207 * called periodically with 'progress' as a floating-point value in
208 * the range of [0.0 .. 1.0] indicating the progress made so far in
209 * the upgrade process.
212 notmuch_database_upgrade (notmuch_database_t *database,
213 void (*progress_notify) (void *closure,
217 /* Retrieve a directory object from the database for 'path'.
219 * Here, 'path' should be a path relative to the path of 'database'
220 * (see notmuch_database_get_path), or else should be an absolute path
221 * with initial components that match the path of 'database'.
223 notmuch_directory_t *
224 notmuch_database_get_directory (notmuch_database_t *database,
227 /* Add a new message to the given notmuch database.
229 * Here,'filename' should be a path relative to the path of
230 * 'database' (see notmuch_database_get_path), or else should be an
231 * absolute filename with initial components that match the path of
234 * The file should be a single mail message (not a multi-message mbox)
235 * that is expected to remain at its current location, (since the
236 * notmuch database will reference the filename, and will not copy the
237 * entire contents of the file.
239 * If 'message' is not NULL, then, on successful return '*message'
240 * will be initialized to a message object that can be used for things
241 * such as adding tags to the just-added message. The user should call
242 * notmuch_message_destroy when done with the message. On any failure
243 * '*message' will be set to NULL.
247 * NOTMUCH_STATUS_SUCCESS: Message successfully added to database.
249 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: Message has the same message
250 * ID as another message already in the database. The new
251 * filename was successfully added to the message in the database
252 * (if not already present).
254 * NOTMUCH_STATUS_FILE_ERROR: an error occurred trying to open the
255 * file, (such as permission denied, or file not found,
256 * etc.). Nothing added to the database.
258 * NOTMUCH_STATUS_FILE_NOT_EMAIL: the contents of filename don't look
259 * like an email message. Nothing added to the database.
261 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
262 * mode so no message can be added.
265 notmuch_database_add_message (notmuch_database_t *database,
266 const char *filename,
267 notmuch_message_t **message);
269 /* Remove a message from the given notmuch database.
271 * Note that only this particular filename association is removed from
272 * the database. If the same message (as determined by the message ID)
273 * is still available via other filenames, then the message will
274 * persist in the database for those filenames. When the last filename
275 * is removed for a particular message, the database content for that
276 * message will be entirely removed.
280 * NOTMUCH_STATUS_SUCCESS: The last filename was removed and the
281 * message was removed from the database.
283 * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: This filename was removed but
284 * the message persists in the database with at least one other
287 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
288 * mode so no message can be removed.
291 notmuch_database_remove_message (notmuch_database_t *database,
292 const char *filename);
294 /* Find a message with the given message_id.
296 * If the database contains a message with the given message_id, then
297 * a new notmuch_message_t object is returned. The caller should call
298 * notmuch_message_destroy when done with the message.
300 * If no message is found with the given message_id or if an
301 * out-of-memory situation occurs, this function returns NULL.
304 notmuch_database_find_message (notmuch_database_t *database,
305 const char *message_id);
307 /* Return a list of all tags found in the database.
309 * This function creates a list of all tags found in the database. The
310 * resulting list contains all tags from all messages found in the database.
312 * On error this function returns NULL.
315 notmuch_database_get_all_tags (notmuch_database_t *db);
317 /* Create a new query for 'database'.
319 * Here, 'database' should be an open database, (see
320 * notmuch_database_open and notmuch_database_create).
322 * For the query string, we'll document the syntax here more
323 * completely in the future, but it's likely to be a specialized
324 * version of the general Xapian query syntax:
326 * http://xapian.org/docs/queryparser.html
328 * As a special case, passing a length-zero string, (that is ""), will
329 * result in a query that returns all messages in the database.
331 * See notmuch_query_set_sort for controlling the order of results.
332 * See notmuch_query_search_messages and notmuch_query_search_threads
333 * to actually execute the query.
335 * User should call notmuch_query_destroy when finished with this
338 * Will return NULL if insufficient memory is available.
341 notmuch_query_create (notmuch_database_t *database,
342 const char *query_string);
344 /* Sort values for notmuch_query_set_sort */
346 NOTMUCH_SORT_OLDEST_FIRST,
347 NOTMUCH_SORT_NEWEST_FIRST,
348 NOTMUCH_SORT_MESSAGE_ID
351 /* Specify the sorting desired for this query. */
353 notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort);
355 /* Execute a query for threads, returning a notmuch_threads_t object
356 * which can be used to iterate over the results. The returned threads
357 * object is owned by the query and as such, will only be valid until
358 * notmuch_query_destroy.
360 * Typical usage might be:
362 * notmuch_query_t *query;
363 * notmuch_threads_t *threads;
364 * notmuch_thread_t *thread;
366 * query = notmuch_query_create (database, query_string);
368 * for (threads = notmuch_query_search_threads (query);
369 * notmuch_threads_valid (threads);
370 * notmuch_threads_move_to_next (threads))
372 * thread = notmuch_threads_get (threads);
374 * notmuch_thread_destroy (thread);
377 * notmuch_query_destroy (query);
379 * Note: If you are finished with a thread before its containing
380 * query, you can call notmuch_thread_destroy to clean up some memory
381 * sooner (as in the above example). Otherwise, if your thread objects
382 * are long-lived, then you don't need to call notmuch_thread_destroy
383 * and all the memory will still be reclaimed when the query is
386 * Note that there's no explicit destructor needed for the
387 * notmuch_threads_t object. (For consistency, we do provide a
388 * notmuch_threads_destroy function, but there's no good reason
389 * to call it if the query is about to be destroyed).
392 notmuch_query_search_threads (notmuch_query_t *query);
394 /* Execute a query for messages, returning a notmuch_messages_t object
395 * which can be used to iterate over the results. The returned
396 * messages object is owned by the query and as such, will only be
397 * valid until notmuch_query_destroy.
399 * Typical usage might be:
401 * notmuch_query_t *query;
402 * notmuch_messages_t *messages;
403 * notmuch_message_t *message;
405 * query = notmuch_query_create (database, query_string);
407 * for (messages = notmuch_query_search_messages (query);
408 * notmuch_messages_valid (messages);
409 * notmuch_messages_move_to_next (messages))
411 * message = notmuch_messages_get (messages);
413 * notmuch_message_destroy (message);
416 * notmuch_query_destroy (query);
418 * Note: If you are finished with a message before its containing
419 * query, you can call notmuch_message_destroy to clean up some memory
420 * sooner (as in the above example). Otherwise, if your message
421 * objects are long-lived, then you don't need to call
422 * notmuch_message_destroy and all the memory will still be reclaimed
423 * when the query is destroyed.
425 * Note that there's no explicit destructor needed for the
426 * notmuch_messages_t object. (For consistency, we do provide a
427 * notmuch_messages_destroy function, but there's no good
428 * reason to call it if the query is about to be destroyed).
431 notmuch_query_search_messages (notmuch_query_t *query);
433 /* Destroy a notmuch_query_t along with any associated resources.
435 * This will in turn destroy any notmuch_threads_t and
436 * notmuch_messages_t objects generated by this query, (and in
437 * turn any notmuch_thread_t and notmuch_message_t objects generated
438 * from those results, etc.), if such objects haven't already been
442 notmuch_query_destroy (notmuch_query_t *query);
444 /* Is the given 'threads' iterator pointing at a valid thread.
446 * When this function returns TRUE, notmuch_threads_get will return a
447 * valid object. Whereas when this function returns FALSE,
448 * notmuch_threads_get will return NULL.
450 * See the documentation of notmuch_query_search_threads for example
451 * code showing how to iterate over a notmuch_threads_t object.
454 notmuch_threads_valid (notmuch_threads_t *threads);
456 /* Get the current thread from 'threads' as a notmuch_thread_t.
458 * Note: The returned thread belongs to 'threads' and has a lifetime
459 * identical to it (and the query to which it belongs).
461 * See the documentation of notmuch_query_search_threads for example
462 * code showing how to iterate over a notmuch_threads_t object.
464 * If an out-of-memory situation occurs, this function will return
468 notmuch_threads_get (notmuch_threads_t *threads);
470 /* Move the 'threads' iterator to the next thread.
472 * If 'threads' is already pointing at the last thread then the
473 * iterator will be moved to a point just beyond that last thread,
474 * (where notmuch_threads_valid will return FALSE and
475 * notmuch_threads_get will return NULL).
477 * See the documentation of notmuch_query_search_threads for example
478 * code showing how to iterate over a notmuch_threads_t object.
481 notmuch_threads_move_to_next (notmuch_threads_t *threads);
483 /* Destroy a notmuch_threads_t object.
485 * It's not strictly necessary to call this function. All memory from
486 * the notmuch_threads_t object will be reclaimed when the
487 * containg query object is destroyed.
490 notmuch_threads_destroy (notmuch_threads_t *threads);
492 /* Return an estimate of the number of messages matching a search
494 * This function performs a search and returns Xapian's best
495 * guess as to number of matching messages.
498 notmuch_query_count_messages (notmuch_query_t *query);
500 /* Get the thread ID of 'thread'.
502 * The returned string belongs to 'thread' and as such, should not be
503 * modified by the caller and will only be valid for as long as the
504 * thread is valid, (which is until notmuch_thread_destroy or until
505 * the query from which it derived is destroyed).
508 notmuch_thread_get_thread_id (notmuch_thread_t *thread);
510 /* Get the total number of messages in 'thread'.
512 * This count consists of all messages in the database belonging to
513 * this thread. Contrast with notmuch_thread_get_matched_messages() .
516 notmuch_thread_get_total_messages (notmuch_thread_t *thread);
518 /* Get a notmuch_messages_t iterator for the top-level messages in
521 * This iterator will not necessarily iterate over all of the messages
522 * in the thread. It will only iterate over the messages in the thread
523 * which are not replies to other messages in the thread.
525 * To iterate over all messages in the thread, the caller will need to
526 * iterate over the result of notmuch_message_get_replies for each
527 * top-level message (and do that recursively for the resulting
531 notmuch_thread_get_toplevel_messages (notmuch_thread_t *thread);
533 /* Get the number of messages in 'thread' that matched the search.
535 * This count includes only the messages in this thread that were
536 * matched by the search from which the thread was created. Contrast
537 * with notmuch_thread_get_total_messages() .
540 notmuch_thread_get_matched_messages (notmuch_thread_t *thread);
542 /* Get the authors of 'thread'
544 * The returned string is a comma-separated list of the names of the
545 * authors of mail messages in the query results that belong to this
548 * The returned string belongs to 'thread' and as such, should not be
549 * modified by the caller and will only be valid for as long as the
550 * thread is valid, (which is until notmuch_thread_destroy or until
551 * the query from which it derived is destroyed).
554 notmuch_thread_get_authors (notmuch_thread_t *thread);
556 /* Get the subject of 'thread'
558 * The subject is taken from the first message (according to the query
559 * order---see notmuch_query_set_sort) in the query results that
560 * belongs to this thread.
562 * The returned string belongs to 'thread' and as such, should not be
563 * modified by the caller and will only be valid for as long as the
564 * thread is valid, (which is until notmuch_thread_destroy or until
565 * the query from which it derived is destroyed).
568 notmuch_thread_get_subject (notmuch_thread_t *thread);
570 /* Get the date of the oldest message in 'thread' as a time_t value.
573 notmuch_thread_get_oldest_date (notmuch_thread_t *thread);
575 /* Get the date of the newest message in 'thread' as a time_t value.
578 notmuch_thread_get_newest_date (notmuch_thread_t *thread);
580 /* Get the tags for 'thread', returning a notmuch_tags_t object which
581 * can be used to iterate over all tags.
583 * Note: In the Notmuch database, tags are stored on individual
584 * messages, not on threads. So the tags returned here will be all
585 * tags of the messages which matched the search and which belong to
588 * The tags object is owned by the thread and as such, will only be
589 * valid for as long as the thread is valid, (for example, until
590 * notmuch_thread_destroy or until the query from which it derived is
593 * Typical usage might be:
595 * notmuch_thread_t *thread;
596 * notmuch_tags_t *tags;
599 * thread = notmuch_threads_get (threads);
601 * for (tags = notmuch_thread_get_tags (thread);
602 * notmuch_tags_valid (tags);
603 * notmuch_result_move_to_next (tags))
605 * tag = notmuch_tags_get (tags);
609 * notmuch_thread_destroy (thread);
611 * Note that there's no explicit destructor needed for the
612 * notmuch_tags_t object. (For consistency, we do provide a
613 * notmuch_tags_destroy function, but there's no good reason to call
614 * it if the message is about to be destroyed).
617 notmuch_thread_get_tags (notmuch_thread_t *thread);
619 /* Destroy a notmuch_thread_t object. */
621 notmuch_thread_destroy (notmuch_thread_t *thread);
623 /* Is the given 'messages' iterator pointing at a valid message.
625 * When this function returns TRUE, notmuch_messages_get will return a
626 * valid object. Whereas when this function returns FALSE,
627 * notmuch_messages_get will return NULL.
629 * See the documentation of notmuch_query_search_messages for example
630 * code showing how to iterate over a notmuch_messages_t object.
633 notmuch_messages_valid (notmuch_messages_t *messages);
635 /* Get the current message from 'messages' as a notmuch_message_t.
637 * Note: The returned message belongs to 'messages' and has a lifetime
638 * identical to it (and the query to which it belongs).
640 * See the documentation of notmuch_query_search_messages for example
641 * code showing how to iterate over a notmuch_messages_t object.
643 * If an out-of-memory situation occurs, this function will return
647 notmuch_messages_get (notmuch_messages_t *messages);
649 /* Move the 'messages' iterator to the next message.
651 * If 'messages' is already pointing at the last message then the
652 * iterator will be moved to a point just beyond that last message,
653 * (where notmuch_messages_valid will return FALSE and
654 * notmuch_messages_get will return NULL).
656 * See the documentation of notmuch_query_search_messages for example
657 * code showing how to iterate over a notmuch_messages_t object.
660 notmuch_messages_move_to_next (notmuch_messages_t *messages);
662 /* Destroy a notmuch_messages_t object.
664 * It's not strictly necessary to call this function. All memory from
665 * the notmuch_messages_t object will be reclaimed when the containing
666 * query object is destroyed.
669 notmuch_messages_destroy (notmuch_messages_t *messages);
671 /* Return a list of tags from all messages.
673 * The resulting list is guaranteed not to contain duplicated tags.
675 * WARNING: You can no longer iterate over messages after calling this
676 * function, because the iterator will point at the end of the list.
677 * We do not have a function to reset the iterator yet and the only
678 * way how you can iterate over the list again is to recreate the
681 * The function returns NULL on error.
684 notmuch_messages_collect_tags (notmuch_messages_t *messages);
686 /* Get the message ID of 'message'.
688 * The returned string belongs to 'message' and as such, should not be
689 * modified by the caller and will only be valid for as long as the
690 * message is valid, (which is until the query from which it derived
693 * This function will not return NULL since Notmuch ensures that every
694 * message has a unique message ID, (Notmuch will generate an ID for a
695 * message if the original file does not contain one).
698 notmuch_message_get_message_id (notmuch_message_t *message);
700 /* Get the thread ID of 'message'.
702 * The returned string belongs to 'message' and as such, should not be
703 * modified by the caller and will only be valid for as long as the
704 * message is valid, (for example, until the user calls
705 * notmuch_message_destroy on 'message' or until a query from which it
706 * derived is destroyed).
708 * This function will not return NULL since Notmuch ensures that every
709 * message belongs to a single thread.
712 notmuch_message_get_thread_id (notmuch_message_t *message);
714 /* Get a notmuch_messages_t iterator for all of the replies to
717 * Note: This call only makes sense if 'message' was ultimately
718 * obtained from a notmuch_thread_t object, (such as by coming
719 * directly from the result of calling notmuch_thread_get_
720 * toplevel_messages or by any number of subsequent
721 * calls to notmuch_message_get_replies).
723 * If 'message' was obtained through some non-thread means, (such as
724 * by a call to notmuch_query_search_messages), then this function
727 * If there are no replies to 'message', this function will return
728 * NULL. (Note that notmuch_messages_valid will accept that NULL
729 * value as legitimate, and simply return FALSE for it.)
732 notmuch_message_get_replies (notmuch_message_t *message);
734 /* Get a filename for the email corresponding to 'message'.
736 * The returned filename is an absolute filename, (the initial
737 * component will match notmuch_database_get_path() ).
739 * The returned string belongs to the message so should not be
740 * modified or freed by the caller (nor should it be referenced after
741 * the message is destroyed).
743 * Note: If this message corresponds to multiple files in the mail
744 * store, (that is, multiple files contain identical message IDs),
745 * this function will arbitrarily return a single one of those
749 notmuch_message_get_filename (notmuch_message_t *message);
752 typedef enum _notmuch_message_flag {
753 NOTMUCH_MESSAGE_FLAG_MATCH,
754 } notmuch_message_flag_t;
756 /* Get a value of a flag for the email corresponding to 'message'. */
758 notmuch_message_get_flag (notmuch_message_t *message,
759 notmuch_message_flag_t flag);
761 /* Set a value of a flag for the email corresponding to 'message'. */
763 notmuch_message_set_flag (notmuch_message_t *message,
764 notmuch_message_flag_t flag, notmuch_bool_t value);
766 /* Get the date of 'message' as a time_t value.
768 * For the original textual representation of the Date header from the
769 * message call notmuch_message_get_header() with a header value of
772 notmuch_message_get_date (notmuch_message_t *message);
774 /* Get the value of the specified header from 'message'.
776 * The value will be read from the actual message file, not from the
777 * notmuch database. The header name is case insensitive.
779 * The returned string belongs to the message so should not be
780 * modified or freed by the caller (nor should it be referenced after
781 * the message is destroyed).
783 * Returns an empty string ("") if the message does not contain a
784 * header line matching 'header'. Returns NULL if any error occurs.
787 notmuch_message_get_header (notmuch_message_t *message, const char *header);
789 /* Get the tags for 'message', returning a notmuch_tags_t object which
790 * can be used to iterate over all tags.
792 * The tags object is owned by the message and as such, will only be
793 * valid for as long as the message is valid, (which is until the
794 * query from which it derived is destroyed).
796 * Typical usage might be:
798 * notmuch_message_t *message;
799 * notmuch_tags_t *tags;
802 * message = notmuch_database_find_message (database, message_id);
804 * for (tags = notmuch_message_get_tags (message);
805 * notmuch_tags_valid (tags);
806 * notmuch_result_move_to_next (tags))
808 * tag = notmuch_tags_get (tags);
812 * notmuch_message_destroy (message);
814 * Note that there's no explicit destructor needed for the
815 * notmuch_tags_t object. (For consistency, we do provide a
816 * notmuch_tags_destroy function, but there's no good reason to call
817 * it if the message is about to be destroyed).
820 notmuch_message_get_tags (notmuch_message_t *message);
822 /* The longest possible tag value. */
823 #define NOTMUCH_TAG_MAX 200
825 /* Add a tag to the given message.
829 * NOTMUCH_STATUS_SUCCESS: Tag successfully added to message
831 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
833 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
834 * (exceeds NOTMUCH_TAG_MAX)
836 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
837 * mode so message cannot be modified.
840 notmuch_message_add_tag (notmuch_message_t *message, const char *tag);
842 /* Remove a tag from the given message.
846 * NOTMUCH_STATUS_SUCCESS: Tag successfully removed from message
848 * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
850 * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
851 * (exceeds NOTMUCH_TAG_MAX)
853 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
854 * mode so message cannot be modified.
857 notmuch_message_remove_tag (notmuch_message_t *message, const char *tag);
859 /* Remove all tags from the given message.
861 * See notmuch_message_freeze for an example showing how to safely
862 * replace tag values.
864 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
865 * mode so message cannot be modified.
868 notmuch_message_remove_all_tags (notmuch_message_t *message);
870 /* Freeze the current state of 'message' within the database.
872 * This means that changes to the message state, (via
873 * notmuch_message_add_tag, notmuch_message_remove_tag, and
874 * notmuch_message_remove_all_tags), will not be committed to the
875 * database until the message is thawed with notmuch_message_thaw.
877 * Multiple calls to freeze/thaw are valid and these calls will
878 * "stack". That is there must be as many calls to thaw as to freeze
879 * before a message is actually thawed.
881 * The ability to do freeze/thaw allows for safe transactions to
882 * change tag values. For example, explicitly setting a message to
883 * have a given set of tags might look like this:
885 * notmuch_message_freeze (message);
887 * notmuch_message_remove_all_tags (message);
889 * for (i = 0; i < NUM_TAGS; i++)
890 * notmuch_message_add_tag (message, tags[i]);
892 * notmuch_message_thaw (message);
894 * With freeze/thaw used like this, the message in the database is
895 * guaranteed to have either the full set of original tag values, or
896 * the full set of new tag values, but nothing in between.
898 * Imagine the example above without freeze/thaw and the operation
899 * somehow getting interrupted. This could result in the message being
900 * left with no tags if the interruption happened after
901 * notmuch_message_remove_all_tags but before notmuch_message_add_tag.
905 * NOTMUCH_STATUS_SUCCESS: Message successfully frozen.
907 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
908 * mode so message cannot be modified.
911 notmuch_message_freeze (notmuch_message_t *message);
913 /* Thaw the current 'message', synchronizing any changes that may have
914 * occurred while 'message' was frozen into the notmuch database.
916 * See notmuch_message_freeze for an example of how to use this
917 * function to safely provide tag changes.
919 * Multiple calls to freeze/thaw are valid and these calls with
920 * "stack". That is there must be as many calls to thaw as to freeze
921 * before a message is actually thawed.
925 * NOTMUCH_STATUS_SUCCESS: Message successfully thawed, (or at least
926 * its frozen count has successfully been reduced by 1).
928 * NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW: An attempt was made to thaw
929 * an unfrozen message. That is, there have been an unbalanced
930 * number of calls to notmuch_message_freeze and
931 * notmuch_message_thaw.
934 notmuch_message_thaw (notmuch_message_t *message);
936 /* Destroy a notmuch_message_t object.
938 * It can be useful to call this function in the case of a single
939 * query object with many messages in the result, (such as iterating
940 * over the entire database). Otherwise, it's fine to never call this
941 * function and there will still be no memory leaks. (The memory from
942 * the messages get reclaimed when the containing query is destroyed.)
945 notmuch_message_destroy (notmuch_message_t *message);
947 /* Is the given 'tags' iterator pointing at a valid tag.
949 * When this function returns TRUE, notmuch_tags_get will return a
950 * valid string. Whereas when this function returns FALSE,
951 * notmuch_tags_get will return NULL.
953 * See the documentation of notmuch_message_get_tags for example code
954 * showing how to iterate over a notmuch_tags_t object.
957 notmuch_tags_valid (notmuch_tags_t *tags);
959 /* Get the current tag from 'tags' as a string.
961 * Note: The returned string belongs to 'tags' and has a lifetime
962 * identical to it (and the query to which it ultimately belongs).
964 * See the documentation of notmuch_message_get_tags for example code
965 * showing how to iterate over a notmuch_tags_t object.
968 notmuch_tags_get (notmuch_tags_t *tags);
970 /* Move the 'tags' iterator to the next tag.
972 * If 'tags' is already pointing at the last tag then the iterator
973 * will be moved to a point just beyond that last tag, (where
974 * notmuch_tags_valid will return FALSE and notmuch_tags_get will
977 * See the documentation of notmuch_message_get_tags for example code
978 * showing how to iterate over a notmuch_tags_t object.
981 notmuch_tags_move_to_next (notmuch_tags_t *tags);
983 /* Destroy a notmuch_tags_t object.
985 * It's not strictly necessary to call this function. All memory from
986 * the notmuch_tags_t object will be reclaimed when the containing
987 * message or query objects are destroyed.
990 notmuch_tags_destroy (notmuch_tags_t *tags);
992 /* Store an mtime within the database for 'directory'.
994 * The 'directory' should be an object retrieved from the database
995 * with notmuch_database_get_directory for a particular path.
997 * The intention is for the caller to use the mtime to allow efficient
998 * identification of new messages to be added to the database. The
999 * recommended usage is as follows:
1001 * o Read the mtime of a directory from the filesystem
1003 * o Call add_message for all mail files in the directory
1005 * o Call notmuch_directory_set_mtime with the mtime read from the
1008 * Then, when wanting to check for updates to the directory in the
1009 * future, the client can call notmuch_directory_get_mtime and know
1010 * that it only needs to add files if the mtime of the directory and
1011 * files are newer than the stored timestamp.
1013 * Note: The notmuch_directory_get_mtime function does not allow the
1014 * caller to distinguish a timestamp of 0 from a non-existent
1015 * timestamp. So don't store a timestamp of 0 unless you are
1016 * comfortable with that.
1020 * NOTMUCH_STATUS_SUCCESS: mtime successfully stored in database.
1022 * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception
1023 * occurred, mtime not stored.
1025 * NOTMUCH_STATUS_READ_ONLY_DATABASE: Database was opened in read-only
1026 * mode so directory mtime cannot be modified.
1029 notmuch_directory_set_mtime (notmuch_directory_t *directory,
1032 /* Get the mtime of a directory, (as previously stored with
1033 * notmuch_directory_set_mtime).
1035 * Returns 0 if no mtime has previously been stored for this
1038 notmuch_directory_get_mtime (notmuch_directory_t *directory);
1040 /* Get a notmuch_filenames_t iterator listing all the filenames of
1041 * messages in the database within the given directory.
1043 * The returned filenames will be the basename-entries only (not
1044 * complete paths). */
1045 notmuch_filenames_t *
1046 notmuch_directory_get_child_files (notmuch_directory_t *directory);
1048 /* Get a notmuch_filenams_t iterator listing all the filenames of
1049 * sub-directories in the database within the given directory.
1051 * The returned filenames will be the basename-entries only (not
1052 * complete paths). */
1053 notmuch_filenames_t *
1054 notmuch_directory_get_child_directories (notmuch_directory_t *directory);
1056 /* Destroy a notmuch_directory_t object. */
1058 notmuch_directory_destroy (notmuch_directory_t *directory);
1060 /* Is the given 'filenames' iterator pointing at a valid filename.
1062 * When this function returns TRUE, notmuch_filenames_get will return
1063 * a valid string. Whereas when this function returns FALSE,
1064 * notmuch_filenames_get will return NULL.
1066 * It is acceptable to pass NULL for 'filenames', in which case this
1067 * function will always return FALSE.
1070 notmuch_filenames_valid (notmuch_filenames_t *filenames);
1072 /* Get the current filename from 'filenames' as a string.
1074 * Note: The returned string belongs to 'filenames' and has a lifetime
1075 * identical to it (and the directory to which it ultimately belongs).
1077 * It is acceptable to pass NULL for 'filenames', in which case this
1078 * function will always return NULL.
1081 notmuch_filenames_get (notmuch_filenames_t *filenames);
1083 /* Move the 'filenames' iterator to the next filename.
1085 * If 'filenames' is already pointing at the last filename then the
1086 * iterator will be moved to a point just beyond that last filename,
1087 * (where notmuch_filenames_valid will return FALSE and
1088 * notmuch_filenames_get will return NULL).
1090 * It is acceptable to pass NULL for 'filenames', in which case this
1091 * function will do nothing.
1094 notmuch_filenames_move_to_next (notmuch_filenames_t *filenames);
1096 /* Destroy a notmuch_filenames_t object.
1098 * It's not strictly necessary to call this function. All memory from
1099 * the notmuch_filenames_t object will be reclaimed when the
1100 * containing directory object is destroyed.
1102 * It is acceptable to pass NULL for 'filenames', in which case this
1103 * function will do nothing.
1106 notmuch_filenames_destroy (notmuch_filenames_t *filenames);