[PATCH 1/3] lib: make compact to keep backup until new database in place

diff --git a/e2/b4f9365501d05eedeedb9324cad4811145debd b/e2/b4f9365501d05eedeedb9324cad4811145debd
new file mode 100644 (file)
index 0000000..e0c2bd7
--- /dev/null
+++ b/e2/b4f9365501d05eedeedb9324cad4811145debd
@@ -0,0 +1,141 @@
+Return-Path: <too@guru-group.fi>\r
+X-Original-To: notmuch@notmuchmail.org\r
+Delivered-To: notmuch@notmuchmail.org\r
+Received: from localhost (localhost [127.0.0.1])\r
+       by olra.theworths.org (Postfix) with ESMTP id 152CD431FDD\r
+       for <notmuch@notmuchmail.org>; Mon, 11 Nov 2013 09:56:15 -0800 (PST)\r
+X-Virus-Scanned: Debian amavisd-new at olra.theworths.org\r
+X-Spam-Flag: NO\r
+X-Spam-Score: 0\r
+X-Spam-Level: \r
+X-Spam-Status: No, score=0 tagged_above=-999 required=5 tests=[none]\r
+       autolearn=disabled\r
+Received: from olra.theworths.org ([127.0.0.1])\r
+       by localhost (olra.theworths.org [127.0.0.1]) (amavisd-new, port 10024)\r
+       with ESMTP id lf1FaGgTkvmV for <notmuch@notmuchmail.org>;\r
+       Mon, 11 Nov 2013 09:56:09 -0800 (PST)\r
+Received: from guru.guru-group.fi (guru.guru-group.fi [46.183.73.34])\r
+       by olra.theworths.org (Postfix) with ESMTP id 5D7CC429E4E\r
+       for <notmuch@notmuchmail.org>; Mon, 11 Nov 2013 09:55:58 -0800 (PST)\r
+Received: by guru.guru-group.fi (Postfix, from userid 501)\r
+       id F189E1000E5; Mon, 11 Nov 2013 19:55:43 +0200 (EET)\r
+From: Tomi Ollila <tomi.ollila@iki.fi>\r
+To: notmuch@notmuchmail.org\r
+Subject: [PATCH 1/3] lib: make compact to keep backup until new database in\r
+       place\r
+Date: Mon, 11 Nov 2013 19:55:36 +0200\r
+Message-Id: <1384192538-15291-2-git-send-email-tomi.ollila@iki.fi>\r
+X-Mailer: git-send-email 1.8.0\r
+In-Reply-To: <1384192538-15291-1-git-send-email-tomi.ollila@iki.fi>\r
+References: <1384192538-15291-1-git-send-email-tomi.ollila@iki.fi>\r
+Cc: tomi.ollila@iki.fi\r
+X-BeenThere: notmuch@notmuchmail.org\r
+X-Mailman-Version: 2.1.13\r
+Precedence: list\r
+List-Id: "Use and development of the notmuch mail system."\r
+       <notmuch.notmuchmail.org>\r
+List-Unsubscribe: <http://notmuchmail.org/mailman/options/notmuch>,\r
+       <mailto:notmuch-request@notmuchmail.org?subject=unsubscribe>\r
+List-Archive: <http://notmuchmail.org/pipermail/notmuch>\r
+List-Post: <mailto:notmuch@notmuchmail.org>\r
+List-Help: <mailto:notmuch-request@notmuchmail.org?subject=help>\r
+List-Subscribe: <http://notmuchmail.org/mailman/listinfo/notmuch>,\r
+       <mailto:notmuch-request@notmuchmail.org?subject=subscribe>\r
+X-List-Received-Date: Mon, 11 Nov 2013 17:56:15 -0000\r
+\r
+It is less error prone and window of failure opportunity is smaller\r
+if the old database is always renamed (instead of sometimes rmtree'd)\r
+before new database is put into its place.\r
+Finally rmtree() old database in case old database backup is not kept.\r
+---\r
+ lib/database.cc | 44 ++++++++++++++++++++++++++------------------\r
+ 1 file changed, 26 insertions(+), 18 deletions(-)\r
+\r
+diff --git a/lib/database.cc b/lib/database.cc\r
+index a021bf1..6b656e9 100644\r
+--- a/lib/database.cc\r
++++ b/lib/database.cc\r
+@@ -871,6 +871,7 @@ notmuch_database_compact (const char* path,\r
+     notmuch_status_t ret = NOTMUCH_STATUS_SUCCESS;\r
+     notmuch_database_t *notmuch = NULL;\r
+     struct stat statbuf;\r
++    bool keep_backup;\r
+ \r
+     local = talloc_new (NULL);\r
+     if (! local)\r
+@@ -896,17 +897,25 @@ notmuch_database_compact (const char* path,\r
+       goto DONE;\r
+     }\r
+ \r
+-    if (backup_path != NULL) {\r
+-      if (stat(backup_path, &statbuf) != -1) {\r
+-          fprintf (stderr, "Backup path already exists: %s\n", backup_path);\r
+-          ret = NOTMUCH_STATUS_FILE_ERROR;\r
+-          goto DONE;\r
+-      }\r
+-      if (errno != ENOENT) {\r
+-          fprintf (stderr, "Unknown error while stat()ing backup path: %s\n",\r
+-                   strerror(errno));\r
++    if (backup_path == NULL) {\r
++      if (! (backup_path = talloc_asprintf (local, "%s.old", xapian_path))) {\r
++          ret = NOTMUCH_STATUS_OUT_OF_MEMORY;\r
+           goto DONE;\r
+       }\r
++      keep_backup = FALSE;\r
++    }\r
++    else\r
++      keep_backup = TRUE;\r
++\r
++    if (stat (backup_path, &statbuf) != -1) {\r
++      fprintf (stderr, "Backup path already exists: %s\n", backup_path);\r
++      ret = NOTMUCH_STATUS_FILE_ERROR;\r
++      goto DONE;\r
++    }\r
++    if (errno != ENOENT) {\r
++      fprintf (stderr, "Unknown error while stat()ing backup path: %s\n",\r
++               strerror(errno));\r
++      goto DONE;\r
+     }\r
+ \r
+     try {\r
+@@ -922,14 +931,10 @@ notmuch_database_compact (const char* path,\r
+       goto DONE;\r
+     }\r
+ \r
+-    if (backup_path) {\r
+-      if (rename(xapian_path, backup_path)) {\r
+-          fprintf (stderr, "Error moving old database out of the way\n");\r
+-          ret = NOTMUCH_STATUS_FILE_ERROR;\r
+-          goto DONE;\r
+-      }\r
+-    } else {\r
+-      rmtree(xapian_path);\r
++    if (rename(xapian_path, backup_path)) {\r
++      fprintf (stderr, "Error moving old database out of the way\n");\r
++      ret = NOTMUCH_STATUS_FILE_ERROR;\r
++      goto DONE;\r
+     }\r
+ \r
+     if (rename(compact_xapian_path, xapian_path)) {\r
+@@ -938,6 +943,9 @@ notmuch_database_compact (const char* path,\r
+       goto DONE;\r
+     }\r
+ \r
++    if (! keep_backup)\r
++      rmtree (backup_path);\r
++\r
+ DONE:\r
+     if (notmuch)\r
+       notmuch_database_destroy (notmuch);\r
+@@ -1538,7 +1546,7 @@ _notmuch_database_generate_doc_id (notmuch_database_t *notmuch)\r
+     notmuch->last_doc_id++;\r
+ \r
+     if (notmuch->last_doc_id == 0)\r
+-      INTERNAL_ERROR ("Xapian document IDs are exhausted.\n");        \r
++      INTERNAL_ERROR ("Xapian document IDs are exhausted.\n");\r
+ \r
+     return notmuch->last_doc_id;\r
+ }\r
+-- \r
+1.8.3.1\r
+\r