[gtk+] [broadway] Add stacktrace debugging functions

[Alexander Larsson <alexl src gnome org>]

commit 840df5c7c174150d243a1073aa00c5c5d1008c1a
Author: Alexander Larsson <alexl redhat com>
Date:   Tue Apr 12 10:13:38 2011 +0200

    [broadway] Add stacktrace debugging functions

 gdk/broadway/broadway.js |   56 ++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 56 insertions(+), 0 deletions(-)
---
diff --git a/gdk/broadway/broadway.js b/gdk/broadway/broadway.js
index 1386cb0..150f46c 100644
--- a/gdk/broadway/broadway.js
+++ b/gdk/broadway/broadway.js
@@ -11,6 +11,62 @@ function log(str) {
     logDiv.appendChild(document.createElement('br'));
 }
 
+function getStackTrace()
+{
+    var callstack = [];
+    var isCallstackPopulated = false;
+    try {
+	i.dont.exist+=0;
+    } catch(e) {
+	if (e.stack) { // Firefox
+	    var lines = e.stack.split("\n");
+	    for (var i=0, len=lines.length; i<len; i++) {
+		if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
+		    callstack.push(lines[i]);
+		}
+	    }
+	    // Remove call to getStackTrace()
+	    callstack.shift();
+	    isCallstackPopulated = true;
+	} else if (window.opera && e.message) { // Opera
+	    var lines = e.message.split("\n");
+	    for (var i=0, len=lines.length; i<len; i++) {
+		if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
+		    var entry = lines[i];
+		    // Append next line also since it has the file info
+		    if (lines[i+1]) {
+			entry += " at " + lines[i+1];
+			i++;
+		    }
+		    callstack.push(entry);
+		}
+	    }
+	    // Remove call to getStackTrace()
+	    callstack.shift();
+	    isCallstackPopulated = true;
+	}
+    }
+    if (!isCallstackPopulated) { //IE and Safari
+	var currentFunction = arguments.callee.caller;
+	while (currentFunction) {
+	    var fn = currentFunction.toString();
+	    var fname = fn.substring(fn.indexOf("function") + 8, fn.indexOf("(")) || "anonymous";
+	    callstack.push(fname);
+	    currentFunction = currentFunction.caller;
+	}
+    }
+    return callstack;
+}
+
+function logStackTrace(len) {
+    var callstack = getStackTrace();
+    var end = callstack.length;
+    if (len > 0)
+	end = Math.min(len + 1, end);
+    for (var i = 1; i < end; i++)
+	log(callstack[i]);
+}
+
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     255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,