osc: implement iTerm2’s OSC-9 - desktop notifications

CHANGELOG.md

@@ -60,6 +60,7 @@
 * `tweak.pua-double-width` option to `foot.ini`, letting you force
   _Private Usage Area_ codepoints to be treated as double-width
   characters.
+* OSC 9 desktop notifications (iTerm2 compatible).
 
 
 ### Changed

doc/foot-ctlseqs.7.scd

@@ -579,6 +579,9 @@ All _OSC_ sequences begin with *\\E]*, sometimes abbreviated _OSC_.
 :  Hyperlink (a.k.a HTML-like anchors). _id_ is optional; if assigned,
    all URIs with the same *ID* will be treated as a single
    hyperlink. An empty URI closes the hyperlink.
+|  \\E] 9 ; _msg_ \\E\\ 
+:  iTerm2
+:  Desktop notification, uses *notify* in *foot.ini*(5).
 |  \\E] 10 ; _spec_ \\E\\ 
 :  xterm
 :  Change the default foreground color to _spec_, a color in

osc.c

@@ -521,7 +521,7 @@ osc_notify(struct terminal *term, char *string)
     const char *title = strtok_r(string, ";", &ctx);
     const char *msg = strtok_r(NULL, "\x00", &ctx);
 
-    notify_notify(term, title, msg);
+    notify_notify(term, title, msg != NULL ? msg : "");
 }
 
 static void
@@ -678,6 +678,11 @@ osc_dispatch(struct terminal *term)
         osc_uri(term, string);
         break;
 
+    case 9:
+        /* iTerm2 Growl notifications */
+        osc_notify(term, string);
+        break;
+
     case 10:
     case 11:
     case 17: