compact: preserve backup database until compacted database is in place

[notmuch] / lib / database.cc

diff --git a/lib/database.cc b/lib/database.cc
index 3530cb650afba31748ea6fe9a15221fd8943ba16..d79cc3006d29a204aaa54a762aa30e0a4734ded7 100644 (file)
--- a/lib/database.cc
+++ b/lib/database.cc
@@ -873,6 +873,7 @@ notmuch_database_compact (const char *path,
     notmuch_status_t ret = NOTMUCH_STATUS_SUCCESS;
     notmuch_database_t *notmuch = NULL;
     struct stat statbuf;
+    notmuch_bool_t keep_backup;
 
     local = talloc_new (NULL);
     if (! local)
@@ -898,17 +899,27 @@ notmuch_database_compact (const char *path,
        goto DONE;
     }
 
-    if (backup_path != NULL) {
-       if (stat (backup_path, &statbuf) != -1) {
-           fprintf (stderr, "Backup path already exists: %s\n", backup_path);
-           ret = NOTMUCH_STATUS_FILE_ERROR;
-           goto DONE;
-       }
-       if (errno != ENOENT) {
-           fprintf (stderr, "Unknown error while stat()ing backup path: %s\n",
-                    strerror (errno));
+    if (backup_path == NULL) {
+       if (! (backup_path = talloc_asprintf (local, "%s.old", xapian_path))) {
+           ret = NOTMUCH_STATUS_OUT_OF_MEMORY;
            goto DONE;
        }
+       keep_backup = FALSE;
+    }
+    else {
+       keep_backup = TRUE;
+    }
+
+    if (stat (backup_path, &statbuf) != -1) {
+       fprintf (stderr, "Path already exists: %s\n", backup_path);
+       ret = NOTMUCH_STATUS_FILE_ERROR;
+       goto DONE;
+    }
+    if (errno != ENOENT) {
+       fprintf (stderr, "Unknown error while stat()ing path: %s\n",
+                strerror (errno));
+       ret = NOTMUCH_STATUS_FILE_ERROR;
+       goto DONE;
     }
 
     try {
@@ -924,14 +935,10 @@ notmuch_database_compact (const char *path,
        goto DONE;
     }
 
-    if (backup_path) {
-       if (rename (xapian_path, backup_path)) {
-           fprintf (stderr, "Error moving old database out of the way\n");
-           ret = NOTMUCH_STATUS_FILE_ERROR;
-           goto DONE;
-       }
-    } else {
-       rmtree (xapian_path);
+    if (rename (xapian_path, backup_path)) {
+       fprintf (stderr, "Error moving old database out of the way\n");
+       ret = NOTMUCH_STATUS_FILE_ERROR;
+       goto DONE;
     }
 
     if (rename (compact_xapian_path, xapian_path)) {
@@ -940,6 +947,9 @@ notmuch_database_compact (const char *path,
        goto DONE;
     }
 
+    if (! keep_backup)
+       rmtree (backup_path);
+
   DONE:
     if (notmuch)
        notmuch_database_destroy (notmuch);