* mu4e-proc, mu-cmd-server: update server output

protocol

  - this unbreaks running mu server on non-utf8 locales
  - should also be a bit faster
  - configure.ac: bump version

configure.ac

@@ -14,7 +14,7 @@
 ## along with this program; if not, write to the Free Software Foundation,
 ## Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 
-AC_INIT([mu],[0.9.8.4-dev2],[http://code.google.com/p/mu0/issues/list],[mu])
+AC_INIT([mu],[0.9.8.4-dev3],[http://code.google.com/p/mu0/issues/list],[mu])
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_SRCDIR([src/mu.cc])
 # libtoolize wants to put some stuff in here; if you have an old

emacs/mu4e-proc.el

@@ -34,9 +34,23 @@
 (defvar mu4e~proc-buf nil "Buffer for results data.")
 (defconst mu4e~proc-name "*mu4e-proc*" "Name of the server process, buffer.")
 (defvar mu4e~proc-process nil "The mu-server process")
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 
+;; dealing with the length cookie that precedes expressions
+(defconst mu4e~cookie-pre "\376"
+  "Each expression we get from the backend (mu server) starts with
+   a length cookie:
+   <`mu4e~cookie-pre'><length-in-hex><`mu4e~cookie-post'>.")
+(defconst mu4e~cookie-post "\377"
+    "Each expression we get from the backend (mu server) starts with
+   a length cookie:
+   <`mu4e~cookie-pre'><length-in-hex><`mu4e~cookie-post'>.")
+(defconst mu4e~cookie-matcher-rx
+  (concat mu4e~cookie-pre "\\([[:xdigit:]]+\\)" mu4e~cookie-post)
+  "Regular expression matching the length cookie. Match 1 will be
+the length (in hex).")
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
 
 (defun mu4e~proc-start ()
   "Start the mu server process."
@@ -78,16 +92,20 @@
 
 
 (defun mu4e~proc-eat-sexp-from-buf ()
-  "'Eat' the next s-expression from `mu4e~proc-buf'. `mu4e~proc-buf gets its
-  contents from the mu-servers in the following form:
-       \376<len-of-sexp>\376<sexp>
-Function returns this sexp, or nil if there was none. `mu4e~proc-buf' is
-updated as well, with all processed sexp data removed."
+  "'Eat' the next s-expression from `mu4e~proc-buf'. Note: this is a string,
+not an emacs-buffer. `mu4e~proc-buf gets its contents from the
+mu-servers in the following form:
+   <`mu4e~cookie-pre'><length-in-hex><`mu4e~cookie-post'>
+
+Function returns this sexp, or nil if there was
+none. `mu4e~proc-buf' is updated as well, with all processed sexp
+data removed."
   (when mu4e~proc-buf
-    ;; TODO: maybe try a non-regexp solution?
-    (let* ((b (string-match "\376\\([0-9]+\\)\376" mu4e~proc-buf))
+    ;; mu4e~cookie-matcher-rx:
+    ;;  (concat mu4e~cookie-pre "\\([[:xdigit:]]+\\)]" mu4e~cookie-post)
+    (let* ((b (string-match mu4e~cookie-matcher-rx mu4e~proc-buf))
 	    (sexp-len
-	      (when b (string-to-number (match-string 1 mu4e~proc-buf)))))
+	      (when b (string-to-number (match-string 1 mu4e~proc-buf) 16))))
       ;; does mu4e~proc-buf contain the full sexp?
       (when (and b (>= (length mu4e~proc-buf) (+ sexp-len (match-end 0))))
 	;; clear-up start
@@ -96,7 +114,7 @@ updated as well, with all processed sexp data removed."
 	;; is the sexp, and convert that to utf-8, before we interpret it.
 	(let ((objcons
 		(ignore-errors ;; note: this may fail if we killed the process
-			       ;; in the middle
+		  ;; in the middle
 		  (read-from-string
 		    (decode-coding-string (substring mu4e~proc-buf 0 sexp-len) 'utf-8)))))
 	  (when objcons

src/mu-cmd-server.c

@@ -82,17 +82,26 @@ install_sig_handler (void)
 /************************************************************************/
 
 
+/*
+ * Markers for/after the lenght cookie that precedes the expression we
+ * write to output. We use octal 376, 377 (ie, 0xfe, 0xff) as they
+ * will never occur in utf8 */
 
 
-/* BOX - beginning-of-expression */
-#define BOX "\376"
+#define COOKIE_PRE  '\376'
+#define COOKIE_POST '\377'
 
 static void G_GNUC_PRINTF(1, 2)
 print_expr (const char* frm, ...)
 {
 	char *expr;
 	va_list ap;
-	size_t exprlen;
+	size_t exprlen, lenlen;
+	char cookie[16];
+	static int outfd = 0;
+
+	if (outfd == 0)
+		outfd = fileno (stdout);
 
 	expr    = NULL;
 
@@ -100,8 +109,16 @@ print_expr (const char* frm, ...)
 	exprlen = g_vasprintf (&expr, frm, ap);
 	va_end (ap);
 
-	g_print (BOX "%u" BOX "%s\n", (unsigned)exprlen + 1,
-		 expr);
+	/* this cookie tells the frontend where to expect the next
+	 * expression */
+
+	cookie[0] = COOKIE_PRE;
+	lenlen = sprintf(cookie + 1, "%x", exprlen + 1); /* + 1 for \n */
+	cookie[lenlen + 1] = COOKIE_POST;
+
+	write (outfd, cookie, lenlen + 2); /* + 2 for the 2 BOX */
+	write (outfd, expr, exprlen);
+	write (outfd, "\n", 1);
 
 	g_free (expr);
 }