NOTMUCH_BEGIN_DECLS
+#include <time.h>
+
#ifndef FALSE
#define FALSE 0
#endif
*
* NOTMUCH_STATUS_SUCCESS: No error occurred.
*
+ * NOTMUCH_STATUS_OUT_OF_MEMORY: Out of memory
+ *
+ * XXX: We don't really want to expose this lame XAPIAN_EXCEPTION
+ * value. Instead we should map to things like DATABASE_LOCKED or
+ * whatever.
+ *
* NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception occurred
*
+ * NOTMUCH_STATUS_FILE_ERROR: An error occurred trying to read or
+ * write to a file (this could be file not found, permission
+ * denied, etc.)
+ *
* NOTMUCH_STATUS_FILE_NOT_EMAIL: A file was presented that doesn't
- * appear to be an email message.
+ * appear to be an email message.
+ *
+ * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: A file contains a message ID
+ * that is identical to a message already in the database.
+ *
+ * NOTMUCH_STATUS_NULL_POINTER: The user erroneously passed a NULL
+ * pointer to a notmuch function.
+ *
+ * NOTMUCH_STATUS_TAG_TOO_LONG: A tag value is too long (exceeds
+ * NOTMUCH_TAG_MAX)
+ *
+ * NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW: The notmuch_message_thaw
+ * function has been called more times than notmuch_message_freeze.
+ *
+ * And finally:
+ *
+ * NOTMUCH_STATUS_LAST_STATUS: Not an actual status value. Just a way
+ * to find out how many valid status values there are.
*/
typedef enum _notmuch_status {
NOTMUCH_STATUS_SUCCESS = 0,
+ NOTMUCH_STATUS_OUT_OF_MEMORY,
NOTMUCH_STATUS_XAPIAN_EXCEPTION,
- NOTMUCH_STATUS_FILE_NOT_EMAIL
+ NOTMUCH_STATUS_FILE_ERROR,
+ NOTMUCH_STATUS_FILE_NOT_EMAIL,
+ NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID,
+ NOTMUCH_STATUS_NULL_POINTER,
+ NOTMUCH_STATUS_TAG_TOO_LONG,
+ NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW,
+
+ NOTMUCH_STATUS_LAST_STATUS
} notmuch_status_t;
+/* Get a string representation of a notmuch_status_t value.
+ *
+ * The result is readonly.
+ */
+const char *
+notmuch_status_to_string (notmuch_status_t status);
+
/* Various opaque data types. For each notmuch_<foo>_t see the various
* notmuch_<foo> functions below. */
typedef struct _notmuch_database notmuch_database_t;
typedef struct _notmuch_query notmuch_query_t;
-typedef struct _notmuch_results notmuch_results_t;
+typedef struct _notmuch_thread_results notmuch_thread_results_t;
+typedef struct _notmuch_thread notmuch_thread_t;
+typedef struct _notmuch_message_results notmuch_message_results_t;
typedef struct _notmuch_message notmuch_message_t;
typedef struct _notmuch_tags notmuch_tags_t;
+/* Lookup the default database path.
+ *
+ * This is the path that will be used by notmuch_database_create and
+ * notmuch_database_open if given a NULL path. Specifically it will be
+ * the value of the NOTMUCH_BASE environment variable if set,
+ * otherwise ${HOME}/mail
+ *
+ * Returns a newly allocated string which the caller should free()
+ * when finished with it.
+ */
+char *
+notmuch_database_default_path (void);
+
/* Create a new, empty notmuch database located at 'path'.
*
* The path should be a top-level directory to a collection of
notmuch_database_t *
notmuch_database_create (const char *path);
+/* XXX: I think I'd like this to take an extra argument of
+ * notmuch_status_t* for returning a status value on failure. */
+
/* Open a an existing notmuch database located at 'path'.
*
* The database should have been created at some time in the past,
void
notmuch_database_close (notmuch_database_t *database);
-/* Lookup the default database path.
- *
- * This is the path that will be used by notmuch_database_create and
- * notmuch_database_open if given a NULL path. Specifically it will be
- * the value of the NOTMUCH_BASE environment variable if set,
- * otherwise ${HOME}/mail
- *
- * Returns a newly allocated string which the caller should free()
- * when finished with it.
- */
-char *
-notmuch_database_default_path (void);
-
/* Return the database path of the given database.
*
* The return value is a string owned by notmuch so should not be
const char *
notmuch_database_get_path (notmuch_database_t *database);
+/* Store a timestamp within the database.
+ *
+ * The Notmuch database will not interpret this key nor the timestamp
+ * values at all. It will merely store them together and return the
+ * timestamp when notmuch_database_get_timestamp is called with the
+ * same value for 'key'.
+ *
+ * The intention is for the caller to use the timestamp to allow
+ * efficient identification of new messages to be added to the
+ * database. The recommended usage is as follows:
+ *
+ * o Read the mtime of a directory from the filesystem
+ *
+ * o Call add_message for all mail files in the directory
+ *
+ * o Call notmuch_database_set_timestamp with the path of the
+ * directory as 'key' and the originally read mtime as 'value'.
+ *
+ * Then, when wanting to check for updates to the directory in the
+ * future, the client can call notmuch_database_get_timestamp and know
+ * that it only needs to add files if the mtime of the directory and
+ * files are newer than the stored timestamp.
+ *
+ * Note: The notmuch_database_get_timestamp function does not allow
+ * the caller to distinguish a timestamp of 0 from a non-existent
+ * timestamp. So don't store a timestamp of 0 unless you are
+ * comfortable with that.
+ *
+ * Return value:
+ *
+ * NOTMUCH_STATUS_SUCCESS: Timestamp successfully stored in database.
+ *
+ * NOTMUCH_STATUS_XAPIAN_EXCEPTION: A Xapian exception
+ * occurred. Timestamp not stored.
+ */
+notmuch_status_t
+notmuch_database_set_timestamp (notmuch_database_t *database,
+ const char *key, time_t timestamp);
+
+/* Retrieve a timestamp from the database.
+ *
+ * Returns the timestamp value previously stored by calling
+ * notmuch_database_set_timestamp with the same value for 'key'.
+ *
+ * Returns 0 if no timestamp is stored for 'key' or if any error
+ * occurred querying the database.
+ */
+time_t
+notmuch_database_get_timestamp (notmuch_database_t *database,
+ const char *key);
+
/* Add a new message to the given notmuch database.
*
* Here,'filename' should be a path relative to the the path of
- * 'database' (see notmuch_database_get_path). The file should be a
- * single mail message (not a multi-message mbox) that is expected to
- * remain at its current location, (since the notmuch database will
- * reference the filename, and will not copy the entire contents of
- * the file.
+ * 'database' (see notmuch_database_get_path), or else should be an
+ * absolute filename with initial components that match the path of
+ * 'database'.
+ *
+ * The file should be a single mail message (not a multi-message mbox)
+ * that is expected to remain at its current location, (since the
+ * notmuch database will reference the filename, and will not copy the
+ * entire contents of the file.
+ *
+ * If 'message' is not NULL, then, on successful return '*message'
+ * will be initialized to a message object that can be used for things
+ * such as adding tags to the just-added message. The user should call
+ * notmuch_message_destroy when done with the message. On any failure
+ * '*message' will be set to NULL.
*
* Return value:
*
* NOTMUCH_STATUS_SUCCESS: Message successfully added to database.
*
+ * NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID: Message has the same message
+ * ID as another message already in the database. Nothing added
+ * to the database.
+ *
+ * NOTMUCH_STATUS_FILE_ERROR: an error occurred trying to open the
+ * file, (such as permission denied, or file not found,
+ * etc.). Nothing added to the database.
+ *
* NOTMUCH_STATUS_FILE_NOT_EMAIL: the contents of filename don't look
- * like an email message. Nothing added to the database.
+ * like an email message. Nothing added to the database.
*/
notmuch_status_t
notmuch_database_add_message (notmuch_database_t *database,
- const char *filename);
+ const char *filename,
+ notmuch_message_t **message);
+
+/* Find a message with the given messsage_id.
+ *
+ * If the database contains a message with the given message_id, then
+ * a new notmuch_message_t object is returned. The caller should call
+ * notmuch_message_destroy when done with the message.
+ *
+ * If no message is found with the given message_id or if an
+ * out-of-memory situation occurs, this function returns NULL.
+ */
+notmuch_message_t *
+notmuch_database_find_message (notmuch_database_t *database,
+ const char *message_id);
/* Create a new query for 'database'.
*
*
* http://xapian.org/docs/queryparser.html
*
- * As a special case, passing a value of NOTMUCH_QUERY_ALL for the
- * query string will result in a query that returns all messages in
- * the database.
+ * As a special case, passing a length-zero string, (that is ""), will
+ * result in a query that returns all messages in the database.
*
* See notmuch_query_set_sort for controlling the order of results and
* notmuch_query_search to actually execute the query.
notmuch_query_create (notmuch_database_t *database,
const char *query_string);
-/* Special value to cause notmuch_query_create to return all
- * messages. */
-extern const char *NOTMUCH_QUERY_ALL;
-
/* Sort values for notmuch_query_set_sort */
typedef enum {
NOTMUCH_SORT_DATE_OLDEST_FIRST,
void
notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort);
-/* Execute a query, returning a notmuch_results_t object which can be
- * used to iterate over the results. The results object is owned by
- * the query and as such, will only be valid until notmuch_query_destroy.
+/* Execute a query for threads, returning a notmuch_thread_results_t
+ * object which can be used to iterate over the results. The results
+ * object is owned by the query and as such, will only be valid until
+ * notmuch_query_destroy.
*
* Typical usage might be:
*
* notmuch_query_t *query;
- * notmuch_results_t *results;
+ * notmuch_thread_results_t *results;
+ * notmuch_thread_t *thread;
*
* query = notmuch_query_create (database, query_string);
*
- * for (results = notmuch_query_search (query);
- * notmuch_results_has_more (results);
- * notmuch_result_advance (results))
+ * for (results = notmuch_query_search_threads (query);
+ * notmuch_thread_results_has_more (results);
+ * notmuch_thread_results_advance (results))
* {
- * message = notmuch_results_get (results);
+ * thread = notmuch_thread_results_get (results);
* ....
+ * notmuch_thread_destroy (thread);
* }
*
* notmuch_query_destroy (query);
*
- * Note that there's no explicit destructor for the notmuch_results_t
- * object.
+ * Note: If you are finished with a thread before its containing
+ * query, you can call notmuch_thread_destroy to clean up some memory
+ * sooner (as in the above example). Otherwise, if your thread objects
+ * are long-lived, then you don't need to call notmuch_thread_destroy
+ * and all the memory will still be reclaimed when the query is
+ * destroyed.
+ *
+ * Note that there's no explicit destructor needed for the
+ * notmuch_thread_results_t object. (For consistency, we do provide a
+ * notmuch_thread_results_destroy function, but there's no good reason
+ * to call it if the query is about to be destroyed).
*/
-notmuch_results_t *
-notmuch_query_search (notmuch_query_t *query);
+notmuch_thread_results_t *
+notmuch_query_search_threads (notmuch_query_t *query);
+
+/* Execute a query for messages, returning a notmuch_message_results_t
+ * object which can be used to iterate over the results. The results
+ * object is owned by the query and as such, will only be valid until
+ * notmuch_query_destroy.
+ *
+ * Typical usage might be:
+ *
+ * notmuch_query_t *query;
+ * notmuch_message_results_t *results;
+ * notmuch_message_t *message;
+ *
+ * query = notmuch_query_create (database, query_string);
+ *
+ * for (results = notmuch_query_search_messages (query);
+ * notmuch_message_results_has_more (results);
+ * notmuch_message_results_advance (results))
+ * {
+ * message = notmuch_message_results_get (results);
+ * ....
+ * notmuch_message_destroy (message);
+ * }
+ *
+ * notmuch_query_destroy (query);
+ *
+ * Note: If you are finished with a message before its containing
+ * query, you can call notmuch_message_destroy to clean up some memory
+ * sooner (as in the above example). Otherwise, if your message
+ * objects are long-lived, then you don't need to call
+ * notmuch_message_destroy and all the memory will still be reclaimed
+ * when the query is destroyed.
+ *
+ * Note that there's no explicit destructor needed for the
+ * notmuch_message_results_t object. (For consistency, we do provide a
+ * notmuch_message_results_destroy function, but there's no good
+ * reason to call it if the query is about to be destroyed).
+ */
+notmuch_message_results_t *
+notmuch_query_search_messages (notmuch_query_t *query);
/* Destroy a notmuch_query_t along with any associated resources.
*
- * This will in turn destroy any notmuch_results_t objects generated
- * by this query, (and in turn any notmuch_message_t objects generated
- * from those results, etc.).
+ * This will in turn destroy any notmuch_thread_results_t and
+ * notmuch_message_results_t objects generated by this query, (and in
+ * turn any notmuch_thrad_t and notmuch_message_t objects generated
+ * from those results, etc.), if such objects haven't already been
+ * destroyed.
*/
void
notmuch_query_destroy (notmuch_query_t *query);
-/* Does the given notmuch_results_t object contain any more results.
+/* Does the given notmuch_thread_results_t object contain any more
+ * results.
+ *
+ * When this function returns TRUE, notmuch_thread_results_get will
+ * return a valid object. Whereas when this function returns FALSE,
+ * notmuch_thread_results_get will return NULL.
+ *
+ * See the documentation of notmuch_query_search_threads for example
+ * code showing how to iterate over a notmuch_thread_results_t object.
+ */
+notmuch_bool_t
+notmuch_thread_results_has_more (notmuch_thread_results_t *results);
+
+/* Get the current result from 'results' as a notmuch_thread_t.
+ *
+ * Note: The returned thread belongs to 'results' and has a lifetime
+ * identical to it (and the query to which it belongs).
+ *
+ * See the documentation of notmuch_query_search_threads for example
+ * code showing how to iterate over a notmuch_thread_results_t object.
+ *
+ * If an out-of-memory situation occurs, this function will return
+ * NULL.
+ */
+notmuch_thread_t *
+notmuch_thread_results_get (notmuch_thread_results_t *results);
+
+/* Advance the 'results' iterator to the next result.
+ *
+ * See the documentation of notmuch_query_search_threads for example
+ * code showing how to iterate over a notmuch_thread_results_t object.
+ */
+void
+notmuch_thread_results_advance (notmuch_thread_results_t *results);
+
+/* Destroy a notmuch_thread_results_t object.
+ *
+ * It's not strictly necessary to call this function. All memory from
+ * the notmuch_thread_results_t object will be reclaimed when the
+ * containg query object is destroyed.
+ */
+void
+notmuch_thread_results_destroy (notmuch_thread_results_t *results);
+
+/* Get the thread ID of 'thread'.
+ *
+ * The returned string belongs to 'thread' and as such, should not be
+ * modified by the caller and will only be valid for as long as the
+ * thread is valid, (which is until notmuch_thread_destroy or until
+ * the query from which it derived is destroyed).
+ */
+const char *
+notmuch_thread_get_thread_id (notmuch_thread_t *thread);
+
+/* Get the subject of 'thread'
+ *
+ * The subject is taken from the first message (according to the query
+ * order---see notmuch_query_set_sort) in the query results that
+ * belongs to this thread.
+ *
+ * The returned string belongs to 'thread' and as such, should not be
+ * modified by the caller and will only be valid for as long as the
+ * thread is valid, (which is until notmuch_thread_destroy or until
+ * the query from which it derived is destroyed).
+ */
+const char *
+notmuch_thread_get_subject (notmuch_thread_t *thread);
+
+/* Get the date of the oldest message in 'thread' as a time_t value.
+ */
+time_t
+notmuch_thread_get_oldest_date (notmuch_thread_t *thread);
+
+/* Get the date of the oldest message in 'thread' as a time_t value.
+ */
+time_t
+notmuch_thread_get_newest_date (notmuch_thread_t *thread);
+
+/* Get the tags for 'thread', returning a notmuch_tags_t object which
+ * can be used to iterate over all tags.
+ *
+ * Note: In the Notmuch database, tags are stored on individual
+ * messages, not on threads. So the tags returned here will be all
+ * tags of the messages which matched the search and which belong to
+ * this thread.
+ *
+ * The tags object is owned by the thread and as such, will only be
+ * valid for as long as the thread is valid, (for example, until
+ * notmuch_thread_destroy or until the query from which it derived is
+ * destroyed).
+ *
+ * Typical usage might be:
+ *
+ * notmuch_thread_t *thread;
+ * notmuch_tags_t *tags;
+ * const char *tag;
+ *
+ * thread = notmuch_thread_results_get (thread_results);
+ *
+ * for (tags = notmuch_thread_get_tags (thread);
+ * notmuch_tags_has_more (tags);
+ * notmuch_result_advance (tags))
+ * {
+ * tag = notmuch_tags_get (tags);
+ * ....
+ * }
+ *
+ * notmuch_thread_destroy (thread);
+ *
+ * Note that there's no explicit destructor needed for the
+ * notmuch_tags_t object. (For consistency, we do provide a
+ * notmuch_tags_destroy function, but there's no good reason to call
+ * it if the message is about to be destroyed).
+ */
+notmuch_tags_t *
+notmuch_thread_get_tags (notmuch_thread_t *thread);
+
+/* Destroy a notmuch_thread_t object. */
+void
+notmuch_thread_destroy (notmuch_thread_t *thread);
+
+/* Does the given notmuch_message_results_t object contain any more
+ * results.
*
- * When this function returns TRUE, notmuch_results_get will return a
- * valid object. Whereas when this function returns FALSE,
- * notmuch_results_get will return NULL.
+ * When this function returns TRUE, notmuch_message_results_get will
+ * return a valid object. Whereas when this function returns FALSE,
+ * notmuch_message_results_get will return NULL.
*
- * See the documentation of notmuch_query_search for example code
- * showing how to iterate over a notmuch_results_t object.
+ * See the documentation of notmuch_query_search_messages for example
+ * code showing how to iterate over a notmuch_message_results_t
+ * object.
*/
notmuch_bool_t
-notmuch_results_has_more (notmuch_results_t *results);
+notmuch_message_results_has_more (notmuch_message_results_t *results);
/* Get the current result from 'results' as a notmuch_message_t.
*
* Note: The returned message belongs to 'results' and has a lifetime
* identical to it (and the query to which it belongs).
*
- * See the documentation of notmuch_query_search for example code
- * showing how to iterate over a notmuch_results_t object.
+ * See the documentation of notmuch_query_search_messages for example
+ * code showing how to iterate over a notmuch_message_results_t
+ * object.
+ *
+ * If an out-of-memory situation occurs, this function will return
+ * NULL.
*/
notmuch_message_t *
-notmuch_results_get (notmuch_results_t *results);
+notmuch_message_results_get (notmuch_message_results_t *results);
/* Advance the 'results' iterator to the next result.
*
- * See the documentation of notmuch_query_search for example code
- * showing how to iterate over a notmuch_results_t object.
+ * See the documentation of notmuch_query_search_messages for example
+ * code showing how to iterate over a notmuch_message_results_t
+ * object.
+ */
+void
+notmuch_message_results_advance (notmuch_message_results_t *results);
+
+/* Destroy a notmuch_message_results_t object.
+ *
+ * It's not strictly necessary to call this function. All memory from
+ * the notmuch_message_results_t object will be reclaimed when the
+ * containg query object is destroyed.
*/
void
-notmuch_results_advance (notmuch_results_t *results);
+notmuch_message_results_destroy (notmuch_message_results_t *results);
/* Get the message ID of 'message'.
*
* modified by the caller and will only be valid for as long as the
* message is valid, (which is until the query from which it derived
* is destroyed).
+ *
+ * This function will not return NULL since Notmuch ensures that every
+ * message has a unique message ID, (Notmuch will generate an ID for a
+ * message if the original file does not contain one).
*/
const char *
notmuch_message_get_message_id (notmuch_message_t *message);
+/* Get the thread ID of 'message'.
+ *
+ * The returned string belongs to 'message' and as such, should not be
+ * modified by the caller and will only be valid for as long as the
+ * message is valid, (for example, until the user calls
+ * notmuch_message_destroy on 'message' or until a query from which it
+ * derived is destroyed).
+ *
+ * This function will not return NULL since Notmuch ensures that every
+ * message belongs to a single thread.
+ */
+const char *
+notmuch_message_get_thread_id (notmuch_message_t *message);
+
+/* Get the filename for the email corresponding to 'message'.
+ *
+ * The returned filename is an absolute filename, (the initial
+ * component will match notmuch_database_get_path() ).
+ *
+ * The returned string belongs to the message so should not be
+ * modified or freed by the caller (nor should it be referenced after
+ * the message is destroyed). */
+const char *
+notmuch_message_get_filename (notmuch_message_t *message);
+
+/* Get the date of 'message' as a time_t value.
+ *
+ * For the original textual representation of the Date header from the
+ * message call notmuch_message_get_header() with a header value of
+ * "date". */
+time_t
+notmuch_message_get_date (notmuch_message_t *message);
+
+/* Get the size in bytes of the full header section of 'message'.
+ *
+ * This is useful in conjunction with notmuch_message_get_filename
+ * for separately parsing the message header and content.
+ *
+ * Returns 0 in the case of any error.
+ */
+size_t
+notmuch_message_get_header_size (notmuch_message_t *message);
+
+/* Get the value of the specified header from 'message'.
+ *
+ * The value will be read from the actual message file, not from the
+ * notmuch database. The header name is case insensitive.
+ *
+ * The returned string belongs to the message so should not be
+ * modified or freed by the caller (nor should it be referenced after
+ * the message is destroyed).
+ *
+ * Returns NULL if the message does not contain a header line matching
+ * 'header' of if any error occurs.
+ */
+const char *
+notmuch_message_get_header (notmuch_message_t *message, const char *header);
+
+/* Get the entire set of headers from an email message as a string.
+ *
+ * The value will be read from the actual message file, not from the
+ * notmuch database.
+ *
+ * The returned value is owned by the notmuch message and is valid
+ * only until the message is closed. The caller should copy it if
+ * needing to modify the value or to hold onto it for longer.
+ *
+ * Returns NULL in the case of any error.
+ */
+const char *
+notmuch_message_get_all_headers (notmuch_message_t *message);
+
/* Get the tags for 'message', returning a notmuch_tags_t object which
* can be used to iterate over all tags.
*
* notmuch_tags_t *tags;
* const char *tag;
*
- * message = notmuch_results_get (results);
+ * message = notmuch_database_find_message (database, message_id);
*
* for (tags = notmuch_message_get_tags (message);
* notmuch_tags_has_more (tags);
* notmuch_result_advance (tags))
* {
- * tag = notmuch_tags_get_string (tags);
+ * tag = notmuch_tags_get (tags);
* ....
* }
*
- * Note that there's no explicit destructor for the notmuch_tags_t
- * object.
+ * notmuch_message_destroy (message);
+ *
+ * Note that there's no explicit destructor needed for the
+ * notmuch_tags_t object. (For consistency, we do provide a
+ * notmuch_tags_destroy function, but there's no good reason to call
+ * it if the message is about to be destroyed).
*/
notmuch_tags_t *
notmuch_message_get_tags (notmuch_message_t *message);
-/* Does the given notmuch_tags_t object contain any more results.
+/* The longest possible tag value. */
+#define NOTMUCH_TAG_MAX 200
+
+/* Add a tag to the given message.
+ *
+ * Return value:
+ *
+ * NOTMUCH_STATUS_SUCCESS: Tag successfully added to message
+ *
+ * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
+ *
+ * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
+ * (exceeds NOTMUCH_TAG_MAX)
+ */
+notmuch_status_t
+notmuch_message_add_tag (notmuch_message_t *message, const char *tag);
+
+/* Remove a tag from the given message.
+ *
+ * Return value:
+ *
+ * NOTMUCH_STATUS_SUCCESS: Tag successfully removed from message
+ *
+ * NOTMUCH_STATUS_NULL_POINTER: The 'tag' argument is NULL
+ *
+ * NOTMUCH_STATUS_TAG_TOO_LONG: The length of 'tag' is too long
+ * (exceeds NOTMUCH_TAG_MAX)
+ */
+notmuch_status_t
+notmuch_message_remove_tag (notmuch_message_t *message, const char *tag);
+
+/* Remove all tags from the given message.
+ *
+ * See notmuch_message_freeze for an example showing how to safely
+ * replace tag values.
+ */
+void
+notmuch_message_remove_all_tags (notmuch_message_t *message);
+
+/* Freeze the current state of 'message' within the database.
+ *
+ * This means that changes to the message state, (via
+ * notmuch_message_add_tag, notmuch_message_remove_tag, and
+ * notmuch_message_remove_all_tags), will not be committed to the
+ * database until the message is thawed with notmuch_message_thaw.
+ *
+ * Multiple calls to freeze/thaw are valid and these calls with
+ * "stack". That is there must be as many calls to thaw as to freeze
+ * before a message is actually thawed.
+ *
+ * The ability to do freeze/thaw allows for safe transactions to
+ * change tag values. For example, explicitly setting a message to
+ * have a given set of tags might look like this:
+ *
+ * notmuch_message_freeze (message);
+ *
+ * notmuch_message_remove_all_tags (message);
+ *
+ * for (i = 0; i < NUM_TAGS; i++)
+ * notmuch_message_add_tag (message, tags[i]);
+ *
+ * notmuch_message_thaw (message);
+ *
+ * With freeze/thaw used like this, the message in the database is
+ * guaranteed to have either the full set of original tag value, or
+ * the full set of new tag values, but nothing in between.
+ *
+ * Imagine the example above without freeze/thaw and the operation
+ * somehow getting interrupted. This could result in the message being
+ * left with no tags if the interruption happened after
+ * notmuch_message_remove_all_tags but before notmuch_message_add_tag.
+ */
+void
+notmuch_message_freeze (notmuch_message_t *message);
+
+/* Thaw the current 'message', synchronizing any changes that may have
+ * occurred while 'message' was frozen into the notmuch database.
+ *
+ * See notmuch_message_freeze for an example of how to use this
+ * function to safely provide tag changes.
+ *
+ * Multiple calls to freeze/thaw are valid and these calls with
+ * "stack". That is there must be as many calls to thaw as to freeze
+ * before a message is actually thawed.
+ *
+ * Return value:
+ *
+ * NOTMUCH_STATUS_SUCCESS: Message successfully thawed, (or at least
+ * its frozen count has successfully been reduced by 1).
+ *
+ * NOTMUCH_STATUS_UNBALANCE_FREEZE_THAW: An attempt was made to thaw
+ * an unfrozen message. That is, there have been an unbalanced
+ * number of calls to notmuch_message_freeze and
+ * notmuch_message_thaw.
+ */
+notmuch_status_t
+notmuch_message_thaw (notmuch_message_t *message);
+
+/* Destroy a notmuch_message_t object.
+ *
+ * It can be useful to call this function in the case of a single
+ * query object with many messages in the result, (such as iterating
+ * over the entire database). Otherwise, it's fine to never call this
+ * function and there will still be no memory leaks. (The memory from
+ * the messages get reclaimed when the containing query is destroyed.)
+ */
+void
+notmuch_message_destroy (notmuch_message_t *message);
+
+/* Does the given notmuch_tags_t object contain any more tags.
*
* When this function returns TRUE, notmuch_tags_get will return a
* valid string. Whereas when this function returns FALSE,
notmuch_bool_t
notmuch_tags_has_more (notmuch_tags_t *tags);
-/* Get the current result from 'tags' as a string.
+/* Get the current tag from 'tags' as a string.
*
* Note: The returned string belongs to 'tags' and has a lifetime
* identical to it (and the query to which it utlimately belongs).
* showing how to iterate over a notmuch_tags_t object.
*/
void
-notmuch_tags_advance (notmuch_tags_t *results);
+notmuch_tags_advance (notmuch_tags_t *tags);
+
+/* Destroy a notmuch_tags_t object.
+ *
+ * It's not strictly necessary to call this function. All memory from
+ * the notmuch_tags_t object will be reclaimed when the containg
+ * message or query objects are destroyed.
+ */
+void
+notmuch_tags_destroy (notmuch_tags_t *tags);
NOTMUCH_END_DECLS
projects / notmuch / blobdiff