notmuch/lib/notmuch-private.h, branch 0.22.1

Introduce _notmuch_message_has_term()

2016-04-15T10:07:23Z

It can be useful to easily tell if a given message has a given term associated with it.

Add internal functions to search for alternate doc types

2016-04-15T10:07:23Z

Publicly we are only exposing the non-ghost documents (of "type" "mail"). But internally we might want to inspect the ghost messages as well. This changeset adds two new private interfaces to queries to recover information about alternate document types.

util: move strcase_equal and strcase_hash to util

2015-09-07T12:43:31Z

For future use in both cli and lib.

lib: Add per-message last modification tracking

2015-08-13T21:52:51Z

This adds a new document value that stores the revision of the last modification to message metadata, where the revision number increases monotonically with each database commit. An alternative would be to store the wall-clock time of the last modification of each message. In principle this is simpler and has the advantage that any process can determine the current timestamp without support from libnotmuch. However, even assuming a computer's clock never goes backward and ignoring clock skew in networked environments, this has a fatal flaw. Xapian uses (optimistic) snapshot isolation, which means reads can be concurrent with writes. Given this, consider the following time line with a write and two read transactions: write |-X-A--------------| read 1 |---B---| read 2 |---| The write transaction modifies message X and records the wall-clock time of the modification at A. The writer hangs around for a while and later commits its change. Read 1 is concurrent with the write, so it doesn't see the change to X. It does some query and records the wall-clock time of its results at B. Transaction read 2 later starts after the write commits and queries for changes since wall-clock time B (say the reads are performing an incremental backup). Even though read 1 could not see the change to X, read 2 is told (correctly) that X has not changed since B, the time of the last read. In fact, X changed before wall-clock time A, but the change was not visible until *after* wall-clock time B, so read 2 misses the change to X. This is tricky to solve in full-blown snapshot isolation, but because Xapian serializes writes, we can use a simple, monotonically increasing database revision number. Furthermore, maintaining this revision number requires no more IO than a wall-clock time solution because Xapian already maintains statistics on the upper (and lower) bound of each value stream.

lib: eliminate fprintf from _notmuch_message_file_open

2015-03-28T23:34:15Z

You may wonder why _notmuch_message_file_open_ctx has two parameters. This is because we need sometime to use a ctx which is a notmuch_message_t. While we could get the database from this, there is no easy way in C to tell type we are getting.

lib: add private function to extract the database for a message.

2015-03-28T23:34:15Z

This is needed by logging in functions outside message.cc that take only a notmuch_message_t object.

lib: add a log function with output to a string in notmuch_database_t

2015-03-28T23:34:15Z

In principle in the future this could do something fancier than asprintf.

lib: fix clang build warnings

2015-02-25T22:09:39Z

Fix the following warning produced by clang 3.5.0: lib/message.cc:899:4: warning: comparison of constant 64 with expression of type 'notmuch_message_flag_t' (aka '_notmuch_message_flag') is always true [-Wtautological-constant-out-of-range-compare] ! NOTMUCH_TEST_BIT (message->lazy_flags, flag)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./lib/notmuch-private.h:70:6: note: expanded from macro 'NOTMUCH_TEST_BIT' (_NOTMUCH_VALID_BIT(bit) ? !!((val) & (1ull << (bit))) : 0) ^~~~~~~~~~~~~~~~~~~~~~~ ./lib/notmuch-private.h:68:26: note: expanded from macro '_NOTMUCH_VALID_BIT' ((bit) >= 0 && (bit) < CHAR_BIT * sizeof (unsigned long long)) ~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

lib: abstract bit validity check in bit test/set/clear macros

2015-02-25T22:08:35Z

Reduce duplication in the bit test/set/clear macros. No functional changes.

lib: Internal support for querying and creating ghost messages

2014-10-25T17:26:54Z

This updates the message abstraction to support ghost messages: it adds a message flag that distinguishes regular messages from ghost messages, and an internal function for initializing a newly created (blank) message as a ghost message.