- /* Before we do any real work, (especially before doing a
- * potential SHA-1 computation on the entire file's contents),
- * let's make sure that what we're looking at looks like an
- * actual email message.
- */
- from = _notmuch_message_file_get_header (message_file, "from");
- subject = _notmuch_message_file_get_header (message_file, "subject");
- to = _notmuch_message_file_get_header (message_file, "to");
-
- if ((from == NULL || *from == '\0') &&
- (subject == NULL || *subject == '\0') &&
- (to == NULL || *to == '\0')) {
- ret = NOTMUCH_STATUS_FILE_NOT_EMAIL;
- goto DONE;
- }
-
- /* Now that we're sure it's mail, the first order of business
- * is to find a message ID (or else create one ourselves).
- */
- header = _notmuch_message_file_get_header (message_file, "message-id");
- if (header && *header != '\0') {
- message_id = _parse_message_id (message_file, header, NULL);
-
- /* So the header value isn't RFC-compliant, but it's
- * better than no message-id at all.
- */
- if (message_id == NULL)
- message_id = talloc_strdup (message_file, header);
- }
-
- if (message_id == NULL ) {
- /* No message-id at all, let's generate one by taking a
- * hash over the file's contents.
- */
- char *sha1 = _notmuch_sha1_of_file (filename);
-
- /* If that failed too, something is really wrong. Give up. */
- if (sha1 == NULL) {
- ret = NOTMUCH_STATUS_FILE_ERROR;
- goto DONE;
- }
-
- message_id = talloc_asprintf (message_file, "notmuch-sha1-%s", sha1);
- free (sha1);
- }
-