From: David Bremner Date: Sun, 5 Apr 2015 22:59:05 +0000 (+0900) Subject: [WIP2 03/12] lib: API to retrieve database revision and UUID X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=f456413caa2d1958ed68bb1f3c3d055ba29f9ccd;p=notmuch-archives.git [WIP2 03/12] lib: API to retrieve database revision and UUID --- diff --git a/e6/81748f59f36071895a5084650eac9c49864b14 b/e6/81748f59f36071895a5084650eac9c49864b14 new file mode 100644 index 000000000..08488bb33 --- /dev/null +++ b/e6/81748f59f36071895a5084650eac9c49864b14 @@ -0,0 +1,177 @@ +Return-Path: +X-Original-To: notmuch@notmuchmail.org +Delivered-To: notmuch@notmuchmail.org +Received: from localhost (localhost [127.0.0.1]) + by arlo.cworth.org (Postfix) with ESMTP id 9B8B56DE1B72 + for ; Sun, 5 Apr 2015 16:00:43 -0700 (PDT) +X-Virus-Scanned: Debian amavisd-new at cworth.org +X-Spam-Flag: NO +X-Spam-Score: 0.585 +X-Spam-Level: +X-Spam-Status: No, score=0.585 tagged_above=-999 required=5 tests=[AWL=0.575, + T_HEADER_FROM_DIFFERENT_DOMAINS=0.01] autolearn=disabled +Received: from arlo.cworth.org ([127.0.0.1]) + by localhost (arlo.cworth.org [127.0.0.1]) (amavisd-new, port 10024) + with ESMTP id I7n22twWl2Oh for ; + Sun, 5 Apr 2015 16:00:41 -0700 (PDT) +Received: from mx.xen14.node3324.gplhost.com (gitolite.debian.net + [87.98.215.224]) + by arlo.cworth.org (Postfix) with ESMTPS id 915B96DE1B6F + for ; Sun, 5 Apr 2015 16:00:41 -0700 (PDT) +Received: from remotemail by mx.xen14.node3324.gplhost.com with local (Exim + 4.80) (envelope-from ) + id 1YetWJ-0002nb-U2; Sun, 05 Apr 2015 22:59:59 +0000 +Received: (nullmailer pid 2241 invoked by uid 1000); Sun, 05 Apr 2015 + 22:59:25 -0000 +From: David Bremner +To: notmuch@notmuchmail.org +Subject: [WIP2 03/12] lib: API to retrieve database revision and UUID +Date: Mon, 6 Apr 2015 07:59:05 +0900 +Message-Id: <1428274754-1698-4-git-send-email-david@tethera.net> +X-Mailer: git-send-email 2.1.4 +In-Reply-To: <1428274754-1698-1-git-send-email-david@tethera.net> +References: <1428274754-1698-1-git-send-email-david@tethera.net> +Cc: Austin Clements +X-BeenThere: notmuch@notmuchmail.org +X-Mailman-Version: 2.1.18 +Precedence: list +List-Id: "Use and development of the notmuch mail system." + +List-Unsubscribe: , + +List-Archive: +List-Post: +List-Help: +List-Subscribe: , + +X-List-Received-Date: Sun, 05 Apr 2015 23:00:43 -0000 + +From: Austin Clements + +This exposes the committed database revision to library users along +with a UUID that can be used to detect when revision numbers are no +longer comparable (e.g., because the database has been replaced). +--- + lib/database-private.h | 1 + + lib/database.cc | 11 +++++++++++ + lib/notmuch.h | 18 ++++++++++++++++++ + test/T570-revision-tracking.sh | 37 +++++++++++++++++++++++++++++++++++++ + 4 files changed, 67 insertions(+) + create mode 100755 test/T570-revision-tracking.sh + +diff --git a/lib/database-private.h b/lib/database-private.h +index 5c5a2bb..4e93257 100644 +--- a/lib/database-private.h ++++ b/lib/database-private.h +@@ -170,6 +170,7 @@ struct _notmuch_database { + * under a higher revision number, which can be generated with + * notmuch_database_new_revision. */ + unsigned long revision; ++ const char *uuid; + + Xapian::QueryParser *query_parser; + Xapian::TermGenerator *term_gen; +diff --git a/lib/database.cc b/lib/database.cc +index 4378979..f88bdb3 100644 +--- a/lib/database.cc ++++ b/lib/database.cc +@@ -978,6 +978,8 @@ notmuch_database_open_verbose (const char *path, + notmuch->revision = 0; + else + notmuch->revision = Xapian::sortable_unserialise (last_mod); ++ notmuch->uuid = talloc_strdup ( ++ notmuch, notmuch->xapian_db->get_uuid ().c_str ()); + + notmuch->query_parser = new Xapian::QueryParser; + notmuch->term_gen = new Xapian::TermGenerator; +@@ -1651,6 +1653,15 @@ DONE: + return NOTMUCH_STATUS_SUCCESS; + } + ++unsigned long ++notmuch_database_get_revision (notmuch_database_t *notmuch, ++ const char **uuid) ++{ ++ if (uuid) ++ *uuid = notmuch->uuid; ++ return notmuch->revision; ++} ++ + /* We allow the user to use arbitrarily long paths for directories. But + * we have a term-length limit. So if we exceed that, we'll use the + * SHA-1 of the path for the database term. +diff --git a/lib/notmuch.h b/lib/notmuch.h +index 20c4e01..b6be727 100644 +--- a/lib/notmuch.h ++++ b/lib/notmuch.h +@@ -461,6 +461,24 @@ notmuch_status_t + notmuch_database_end_atomic (notmuch_database_t *notmuch); + + /** ++ * Return the committed database revision and UUID. ++ * ++ * The database revision number increases monotonically with each ++ * commit to the database. Hence, all messages and message changes ++ * committed to the database (that is, visible to readers) have a last ++ * modification revision <= the committed database revision. Any ++ * messages committed in the future will be assigned a modification ++ * revision > the committed database revision. ++ * ++ * The UUID is a NUL-terminated opaque string that uniquely identifies ++ * this database. Two revision numbers are only comparable if they ++ * have the same database UUID. ++ */ ++unsigned long ++notmuch_database_get_revision (notmuch_database_t *notmuch, ++ const char **uuid); ++ ++/** + * Retrieve a directory object from the database for 'path'. + * + * Here, 'path' should be a path relative to the path of 'database' +diff --git a/test/T570-revision-tracking.sh b/test/T570-revision-tracking.sh +new file mode 100755 +index 0000000..8c12740 +--- /dev/null ++++ b/test/T570-revision-tracking.sh +@@ -0,0 +1,37 @@ ++#!/usr/bin/env bash ++test_description="database revision tracking" ++ ++. ./test-lib.sh ++ ++add_email_corpus ++ ++test_begin_subtest "notmuch_database_get_revision" ++test_C ${MAIL_DIR} <<'EOF' ++#include ++#include ++#include ++int main (int argc, char** argv) ++{ ++ notmuch_database_t *db; ++ notmuch_status_t stat; ++ long revision; ++ const char *uuid; ++ ++ unsigned long rev; ++ ++ stat = notmuch_database_open (argv[1], NOTMUCH_DATABASE_MODE_READ_ONLY, &db); ++ if (stat) ++ fputs ("open failed\n", stderr); ++ revision = notmuch_database_get_revision (db, &uuid); ++ printf("revision=%d\nuuid_len=%d\n", revision, strlen (uuid)); ++} ++EOF ++cat <<'EOF' >EXPECTED ++== stdout == ++revision=53 ++uuid_len=36 ++== stderr == ++EOF ++test_expect_equal_file OUTPUT EXPECTED ++ ++test_done +-- +2.1.4 +