Change format for filenames

It seems some tools try to interpret the filename of message files,
even though they shouldn't:
   "Do not try to extract information from unique names."

In particular, they seem to interpret the first part of the name (before
the first dot) as the # of seconds since the Unix epoch (ie.,
time(NULL)). That's not what mu/mu4e put there.

So, let's conform a bit more to the expected filename (as per the
maildir spec), so we're not confusing those tools.

lib/mu-maildir.c

@@ -750,19 +750,21 @@ mu_maildir_get_maildir_from_path (const char* path)
 static char*
 get_new_basename (void)
 {
-	char		date[9];	/* YYYYMMDD */
-	char		hostname[32];	/* should be enough...*/
-	long int	rnd;
-	time_t		now;
+	time_t	now;
+	char	hostname[64];
+		
+	if (gethostname (hostname, sizeof(hostname)) == -1)
+		memcpy (hostname, "localhost", sizeof(hostname));
+	else
+		hostname[sizeof(hostname)-1] = '\0';
 
 	now = time(NULL);
-	strftime (date, sizeof(date), "%Y%m%d", localtime(&now));
-	if (gethostname (hostname, sizeof(hostname)) != 0)
-		memcpy (hostname, "hostname", strlen("hostname"));
-	rnd = random ();
 
-	return g_strdup_printf ("%s-%08x-%s", date,
-				(unsigned)rnd, hostname);
+	return g_strdup_printf ("%u.%8x%8x.%s",
+				(guint)now,
+				g_random_int(),
+				(gint32)g_get_monotonic_time (),
+				hostname);
 }
 
 

lib/tests/test-mu-maildir.c

@@ -481,7 +481,10 @@ test_mu_maildir_get_new_path_new (void)
 		str	= mu_maildir_get_new_path (paths[i].oldpath, NULL,
 						   paths[i].flags, TRUE);
 		newbase = g_path_get_basename (str);
-		assert_matches_regexp (newbase, "\\d{8}-[[:xdigit:]]{8}-[[:alpha:]]+(:2,.*)?");
+		assert_matches_regexp (newbase,
+				       "\\d+\\."
+				       "[[:xdigit:]]{16}\\."
+				       "[[:alpha:]]+(:2,.*)?");
 		g_free (newbase);
 		g_free(str);
 	}

mu4e/mu4e-draft.el

@@ -309,9 +309,10 @@ You can append flags."
 	     (save-match-data
 	       (substring system-name
 		 (string-match "^[^.]+" system-name) (match-end 0))))))
-    (format "%s-%02x%04x-%s:2,%s"
-      (format-time-string "%Y%m%d" (current-time))
-      (random 255) (random 65535) hostname (or flagstr ""))))
+    (format "%s.%04x%04x%04x%04x.%s:2,%s"
+      (format-time-string "%s" (current-time))
+      (random 65535) (random 65535) (random 65535) (random 65535)
+      hostname (or flagstr ""))))
  
 (defun mu4e~draft-common-construct ()
   "Construct the common headers for each message."