notmuch/message.cc

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/* message.cc - Results of message-based searches from a notmuch database
*
* Copyright © 2009 Carl Worth
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see http://www.gnu.org/licenses/ .
*
* Author: Carl Worth <cworth@cworth.org>
*/
#include "notmuch-private.h"
#include "database-private.h"
#include <xapian.h>
struct _notmuch_message {
notmuch_database_t *notmuch;
Xapian::docid doc_id;
char *message_id;
char *filename;
Xapian::Document doc;
};
struct _notmuch_tags {
Xapian::TermIterator iterator;
Xapian::TermIterator iterator_end;
};
struct _notmuch_thread_ids {
char *current;
char *next;
};
/* "128 bits of thread-id ought to be enough for anybody" */
#define NOTMUCH_THREAD_ID_BITS 128
#define NOTMUCH_THREAD_ID_DIGITS (NOTMUCH_THREAD_ID_BITS / 4)
typedef struct _thread_id {
char str[NOTMUCH_THREAD_ID_DIGITS + 1];
} thread_id_t;
/* We end up having to call the destructor explicitly because we had
* to use "placement new" in order to initialize C++ objects within a
* block that we allocated with talloc. So C++ is making talloc
* slightly less simple to use, (we wouldn't need
* talloc_set_destructor at all otherwise).
*/
static int
_notmuch_message_destructor (notmuch_message_t *message)
{
message->doc.~Document ();
return 0;
}
/* Create a new notmuch_message_t object for an existing document in
* the database.
*
* Here, 'talloc owner' is an optional talloc context to which the new
* message will belong. This allows for the caller to not bother
* calling notmuch_message_destroy on the message, and no that all
* memory will be reclaimed with 'talloc_owner' is free. The caller
* still can call notmuch_message_destroy when finished with the
* message if desired.
*
* The 'talloc_owner' argument can also be NULL, in which case the
* caller *is* responsible for calling notmuch_message_destroy.
*
* If no document exists in the database with document ID of 'doc_id'
* then this function returns NULL.
*/
notmuch_message_t *
_notmuch_message_create (const void *talloc_owner,
notmuch_database_t *notmuch,
unsigned int doc_id)
{
notmuch_message_t *message;
message = talloc (talloc_owner, notmuch_message_t);
if (unlikely (message == NULL))
return NULL;
message->notmuch = notmuch;
message->doc_id = doc_id;
message->message_id = NULL; /* lazily created */
message->filename = NULL; /* lazily created */
new (&message->doc) Xapian::Document;
talloc_set_destructor (message, _notmuch_message_destructor);
try {
message->doc = notmuch->xapian_db->get_document (doc_id);
} catch (const Xapian::DocNotFoundError &error) {
talloc_free (message);
return NULL;
}
return message;
}
/* Create a new notmuch_message_t object for a specific message ID,
* (which may or may not already exist in the databas).
*
* Here, 'talloc owner' is an optional talloc context to which the new
* message will belong. This allows for the caller to not bother
* calling notmuch_message_destroy on the message, and no that all
* memory will be reclaimed with 'talloc_owner' is free. The caller
* still can call notmuch_message_destroy when finished with the
* message if desired.
*
* The 'talloc_owner' argument can also be NULL, in which case the
* caller *is* responsible for calling notmuch_message_destroy.
*
* If there is already a document with message ID 'message_id' in the
* database, then the returned message can be used to query/modify the
* document. Otherwise, a new document will be inserted into the
* database before this function returns;
*/
notmuch_message_t *
_notmuch_message_create_for_message_id (const void *talloc_owner,
notmuch_database_t *notmuch,
const char *message_id)
{
notmuch_message_t *message;
Xapian::Document doc;
unsigned int doc_id;
char *term;
message = notmuch_database_find_message (notmuch, message_id);
if (message)
return talloc_steal (talloc_owner, message);
term = talloc_asprintf (NULL, "%s%s",
_find_prefix ("id"), message_id);
doc.add_term (term);
talloc_free (term);
doc.add_value (NOTMUCH_VALUE_MESSAGE_ID, message_id);
doc_id = notmuch->xapian_db->add_document (doc);
return _notmuch_message_create (talloc_owner, notmuch, doc_id);
}
const char *
notmuch_message_get_message_id (notmuch_message_t *message)
{
Xapian::TermIterator i;
if (message->message_id)
return message->message_id;
i = message->doc.termlist_begin ();
i.skip_to (_find_prefix ("id"));
if (i == message->doc.termlist_end ()) {
fprintf (stderr, "Internal error: Message with document ID of %d has no message ID.\n",
message->doc_id);
exit (1);
}
message->message_id = talloc_strdup (message, (*i).c_str () + 1);
return message->message_id;
}
/* Set the filename for 'message' to 'filename'.
*
* XXX: We should still figure out what we want to do for multiple
* files with identical message IDs. We will probably want to store a
* list of filenames here, (so that this will be "add_filename"
* instead of "set_filename"). Which would make this very similar to
* add_thread_ids.
*
* This change will not be reflected in the database until the next
* call to _notmuch_message_set_sync. */
void
_notmuch_message_set_filename (notmuch_message_t *message,
const char *filename)
{
if (message->filename)
talloc_free (message->filename);
message->doc.set_data (filename);
}
const char *
notmuch_message_get_filename (notmuch_message_t *message)
{
std::string filename_str;
if (message->filename)
return message->filename;
filename_str = message->doc.get_data ();
message->filename = talloc_strdup (message, filename_str.c_str ());
return message->filename;
}
/* We end up having to call the destructors explicitly because we had
* to use "placement new" in order to initialize C++ objects within a
* block that we allocated with talloc. So C++ is making talloc
* slightly less simple to use, (we wouldn't need
* talloc_set_destructor at all otherwise).
*/
static int
_notmuch_tags_destructor (notmuch_tags_t *tags)
{
tags->iterator.~TermIterator ();
tags->iterator_end.~TermIterator ();
return 0;
}
notmuch_tags_t *
notmuch_message_get_tags (notmuch_message_t *message)
{
notmuch_tags_t *tags;
tags = talloc (message, notmuch_tags_t);
if (unlikely (tags == NULL))
return NULL;
new (&tags->iterator) Xapian::TermIterator;
new (&tags->iterator_end) Xapian::TermIterator;
talloc_set_destructor (tags, _notmuch_tags_destructor);
tags->iterator = message->doc.termlist_begin ();
tags->iterator.skip_to (_find_prefix ("tag"));
tags->iterator_end = message->doc.termlist_end ();
return tags;
}
notmuch_thread_ids_t *
notmuch_message_get_thread_ids (notmuch_message_t *message)
{
notmuch_thread_ids_t *thread_ids;
std::string id_str;
thread_ids = talloc (message, notmuch_thread_ids_t);
if (unlikely (thread_ids == NULL))
return NULL;
id_str = message->doc.get_value (NOTMUCH_VALUE_THREAD);
thread_ids->next = talloc_strdup (message, id_str.c_str ());
/* Initialize thread_ids->current and terminate first ID. */
notmuch_thread_ids_advance (thread_ids);
return thread_ids;
}
void
_notmuch_message_set_date (notmuch_message_t *message,
const char *date)
{
time_t time_value;
time_value = notmuch_parse_date (date, NULL);
message->doc.add_value (NOTMUCH_VALUE_DATE,
Xapian::sortable_serialise (time_value));
}
void
_notmuch_message_add_thread_id (notmuch_message_t *message,
const char *thread_id)
{
std::string id_str;
_notmuch_message_add_term (message, "thread", thread_id);
id_str = message->doc.get_value (NOTMUCH_VALUE_THREAD);
if (id_str.empty ()) {
message->doc.add_value (NOTMUCH_VALUE_THREAD, thread_id);
} else {
size_t pos;
/* Think about using a hash here if there's any performance
* problem. */
pos = id_str.find (thread_id);
if (pos == std::string::npos) {
id_str.append (",");
id_str.append (thread_id);
message->doc.add_value (NOTMUCH_VALUE_THREAD, id_str);
}
}
}
static void
thread_id_generate (thread_id_t *thread_id)
{
static int seeded = 0;
FILE *dev_random;
uint32_t value;
char *s;
int i;
if (! seeded) {
dev_random = fopen ("/dev/random", "r");
if (dev_random == NULL) {
srand (time (NULL));
} else {
fread ((void *) &value, sizeof (value), 1, dev_random);
srand (value);
fclose (dev_random);
}
seeded = 1;
}
s = thread_id->str;
for (i = 0; i < NOTMUCH_THREAD_ID_DIGITS; i += 8) {
value = rand ();
sprintf (s, "%08x", value);
s += 8;
}
}
void
_notmuch_message_ensure_thread_id (notmuch_message_t *message)
{
/* If not part of any existing thread, generate a new thread_id. */
thread_id_t thread_id;
thread_id_generate (&thread_id);
_notmuch_message_add_term (message, "thread", thread_id.str);
message->doc.add_value (NOTMUCH_VALUE_THREAD, thread_id.str);
}
/* Synchronize changes made to message->doc out into the database. */
void
_notmuch_message_sync (notmuch_message_t *message)
{
Xapian::WritableDatabase *db = message->notmuch->xapian_db;
db->replace_document (message->doc_id, message->doc);
}
/* Add a name:value term to 'message', (the actual term will be
* encoded by prefixing the value with a short prefix). See
* NORMAL_PREFIX and BOOLEAN_PREFIX arrays for the mapping of term
* names to prefix values.
*
* This change will not be reflected in the database until the next
* call to _notmuch_message_set_sync. */
notmuch_private_status_t
_notmuch_message_add_term (notmuch_message_t *message,
const char *prefix_name,
const char *value)
{
char *term;
if (value == NULL)
return NOTMUCH_PRIVATE_STATUS_NULL_POINTER;
term = talloc_asprintf (message, "%s%s",
_find_prefix (prefix_name), value);
if (strlen (term) > NOTMUCH_TERM_MAX)
return NOTMUCH_PRIVATE_STATUS_TERM_TOO_LONG;
message->doc.add_term (term);
talloc_free (term);
return NOTMUCH_PRIVATE_STATUS_SUCCESS;
}
/* Remove a name:value term from 'message', (the actual term will be
* encoded by prefixing the value with a short prefix). See
* NORMAL_PREFIX and BOOLEAN_PREFIX arrays for the mapping of term
* names to prefix values.
*
* This change will not be reflected in the database until the next
* call to _notmuch_message_set_sync. */
notmuch_private_status_t
_notmuch_message_remove_term (notmuch_message_t *message,
const char *prefix_name,
const char *value)
{
char *term;
if (value == NULL)
return NOTMUCH_PRIVATE_STATUS_NULL_POINTER;
term = talloc_asprintf (message, "%s%s",
_find_prefix (prefix_name), value);
if (strlen (term) > NOTMUCH_TERM_MAX)
return NOTMUCH_PRIVATE_STATUS_TERM_TOO_LONG;
message->doc.remove_term (term);
talloc_free (term);
return NOTMUCH_PRIVATE_STATUS_SUCCESS;
}
notmuch_status_t
notmuch_message_add_tag (notmuch_message_t *message, const char *tag)
{
notmuch_private_status_t status;
if (tag == NULL)
return NOTMUCH_STATUS_NULL_POINTER;
if (strlen (tag) > NOTMUCH_TAG_MAX)
return NOTMUCH_STATUS_TAG_TOO_LONG;
status = _notmuch_message_add_term (message, "tag", tag);
if (status) {
fprintf (stderr, "Internal error: _notmuch_message_add_term return unexpected value: %d\n",
status);
exit (1);
}
_notmuch_message_sync (message);
return NOTMUCH_STATUS_SUCCESS;
}
notmuch_status_t
notmuch_message_remove_tag (notmuch_message_t *message, const char *tag)
{
notmuch_private_status_t status;
if (tag == NULL)
return NOTMUCH_STATUS_NULL_POINTER;
if (strlen (tag) > NOTMUCH_TAG_MAX)
return NOTMUCH_STATUS_TAG_TOO_LONG;
status = _notmuch_message_remove_term (message, "tag", tag);
if (status) {
fprintf (stderr, "Internal error: _notmuch_message_remove_term return unexpected value: %d\n",
status);
exit (1);
}
_notmuch_message_sync (message);
return NOTMUCH_STATUS_SUCCESS;
}
void
notmuch_message_destroy (notmuch_message_t *message)
{
talloc_free (message);
}
notmuch_bool_t
notmuch_tags_has_more (notmuch_tags_t *tags)
{
std::string s;
if (tags->iterator == tags->iterator_end)
return FALSE;
s = *tags->iterator;
if (! s.empty () && s[0] == 'L')
return TRUE;
else
return FALSE;
}
const char *
notmuch_tags_get (notmuch_tags_t *tags)
{
return talloc_strdup (tags, (*tags->iterator).c_str () + 1);
}
void
notmuch_tags_advance (notmuch_tags_t *tags)
{
tags->iterator++;
}
void
notmuch_tags_destroy (notmuch_tags_t *tags)
{
talloc_free (tags);
}
notmuch_bool_t
notmuch_thread_ids_has_more (notmuch_thread_ids_t *thread_ids)
{
if (thread_ids->current == NULL || *thread_ids->current == '\0')
return FALSE;
else
return TRUE;
}
const char *
notmuch_thread_ids_get (notmuch_thread_ids_t *thread_ids)
{
return thread_ids->current;
}
void
notmuch_thread_ids_advance (notmuch_thread_ids_t *thread_ids)
{
thread_ids->current = strsep (&thread_ids->next, ",");
}
void
notmuch_thread_ids_destroy (notmuch_thread_ids_t *thread_ids)
{
talloc_free (thread_ids);
}