[notmuch] [PATCH] Handle message renames in mail spool

[Mikhail Gusarov]

In order to handle message renames the following changes were deemed necessary:

* Mtime check on individual files was disabled. As files may be moved around
without changing their mtime, it's necessary to parse them even if they appear
old in case old message was moved. mtime check on directories was kept as moving
files changes mtime of directory.

* If message being parsed is already found in database under different path,
then this message is considered to be moved, path is updated in database and
this file does not undergo further processing.

Note that after applying this patch notmuch still does not handle copying files
(which is harmless, database will point to the last copy of message found during
'notmuch new') and deleting files (which is more serious, as dangling entries
will show up in searches).

Signed-off-by: Mikhail Gusarov <dottedmag at dottedmag.net>
---
 lib/database.cc |   21 +++++++-----
 notmuch-new.c   |   92 ++++++++++++++++++++++++++----------------------------
 2 files changed, 56 insertions(+), 57 deletions(-)

diff --git a/lib/database.cc b/lib/database.cc
index 2c90019..d88efbe 100644
--- a/lib/database.cc
+++ b/lib/database.cc
@@ -990,20 +990,23 @@ notmuch_database_add_message (notmuch_database_t *notmuch,
 	if (private_status == NOTMUCH_PRIVATE_STATUS_NO_DOCUMENT_FOUND) {
 	    _notmuch_message_set_filename (message, filename);
 	    _notmuch_message_add_term (message, "type", "mail");
+
+	    ret = _notmuch_database_link_message (notmuch, message, message_file);
+	    if (ret)
+		goto DONE;
+
+	    date = notmuch_message_file_get_header (message_file, "date");
+	    _notmuch_message_set_date (message, date);
+
+	    _notmuch_message_index_file (message, filename);
+	} else if (strcmp(notmuch_message_get_filename(message), filename)) {
+	    /* Message file has been moved/renamed */
+	    _notmuch_message_set_filename (message, filename);
 	} else {
 	    ret = NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID;
 	    goto DONE;
 	}
 
-	ret = _notmuch_database_link_message (notmuch, message, message_file);
-	if (ret)
-	    goto DONE;
-
-	date = notmuch_message_file_get_header (message_file, "date");
-	_notmuch_message_set_date (message, date);
-
-	_notmuch_message_index_file (message, filename);
-
 	_notmuch_message_sync (message);
     } catch (const Xapian::Error &error) {
 	fprintf (stderr, "A Xapian exception occurred adding message: %s.\n",
diff --git a/notmuch-new.c b/notmuch-new.c
index 0dd2784..d16679c 100644
--- a/notmuch-new.c
+++ b/notmuch-new.c
@@ -174,54 +174,50 @@ add_files_recursive (notmuch_database_t *notmuch,
 	}
 
 	if (S_ISREG (st->st_mode)) {
-	    /* If the file hasn't been modified since the last
-	     * add_files, then we need not look at it. */
-	    if (path_dbtime == 0 || st->st_mtime > path_dbtime) {
-		state->processed_files++;
-
-		status = notmuch_database_add_message (notmuch, next, &message);
-		switch (status) {
-		    /* success */
-		    case NOTMUCH_STATUS_SUCCESS:
-			state->added_messages++;
-			tag_inbox_and_unread (message);
-			break;
-		    /* Non-fatal issues (go on to next file) */
-		    case NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID:
-		        /* Stay silent on this one. */
-			break;
-		    case NOTMUCH_STATUS_FILE_NOT_EMAIL:
-			fprintf (stderr, "Note: Ignoring non-mail file: %s\n",
-				 next);
-			break;
-		    /* Fatal issues. Don't process anymore. */
-		    case NOTMUCH_STATUS_READONLY_DATABASE:
-		    case NOTMUCH_STATUS_XAPIAN_EXCEPTION:
-		    case NOTMUCH_STATUS_OUT_OF_MEMORY:
-			fprintf (stderr, "Error: %s. Halting processing.\n",
-				 notmuch_status_to_string (status));
-			ret = status;
-			goto DONE;
-		    default:
-		    case NOTMUCH_STATUS_FILE_ERROR:
-		    case NOTMUCH_STATUS_NULL_POINTER:
-		    case NOTMUCH_STATUS_TAG_TOO_LONG:
-		    case NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW:
-		    case NOTMUCH_STATUS_LAST_STATUS:
-			INTERNAL_ERROR ("add_message returned unexpected value: %d",  status);
-			goto DONE;
-		}
-
-		if (message) {
-		    notmuch_message_destroy (message);
-		    message = NULL;
-		}
-
-		if (do_add_files_print_progress) {
-		    do_add_files_print_progress = 0;
-		    add_files_print_progress (state);
-		}
-	    }
+            state->processed_files++;
+
+            status = notmuch_database_add_message (notmuch, next, &message);
+            switch (status) {
+                /* success */
+                case NOTMUCH_STATUS_SUCCESS:
+                    state->added_messages++;
+                    tag_inbox_and_unread (message);
+                    break;
+		/* Non-fatal issues (go on to next file) */
+                case NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID:
+                    /* Stay silent on this one. */
+                    break;
+                case NOTMUCH_STATUS_FILE_NOT_EMAIL:
+                    fprintf (stderr, "Note: Ignoring non-mail file: %s\n",
+                             next);
+                    break;
+		/* Fatal issues. Don't process anymore. */
+                case NOTMUCH_STATUS_READONLY_DATABASE:
+                case NOTMUCH_STATUS_XAPIAN_EXCEPTION:
+                case NOTMUCH_STATUS_OUT_OF_MEMORY:
+                    fprintf (stderr, "Error: %s. Halting processing.\n",
+                             notmuch_status_to_string (status));
+                    ret = status;
+                    goto DONE;
+                default:
+                case NOTMUCH_STATUS_FILE_ERROR:
+                case NOTMUCH_STATUS_NULL_POINTER:
+                case NOTMUCH_STATUS_TAG_TOO_LONG:
+                case NOTMUCH_STATUS_UNBALANCED_FREEZE_THAW:
+                case NOTMUCH_STATUS_LAST_STATUS:
+                    INTERNAL_ERROR ("add_message returned unexpected value: %d",  status);
+                    goto DONE;
+            }
+
+            if (message) {
+                notmuch_message_destroy (message);
+                message = NULL;
+            }
+
+            if (do_add_files_print_progress) {
+                do_add_files_print_progress = 0;
+                add_files_print_progress (state);
+            }
 	} else if (S_ISDIR (st->st_mode)) {
 	    status = add_files_recursive (notmuch, next, st, state);
 	    if (status && ret == NOTMUCH_STATUS_SUCCESS)
-- 
1.6.3.3