[gjs] Add "system" module

[Jasper St. Pierre <jstpierre src gnome org>]

commit 667f8a8add3c4dcb8fc2644035283b15926294c1
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Fri Feb 3 12:42:22 2012 -0500

    Add "system" module
    
    There are three functions in here:
    
    * addressOf: Extremely useful when debugging a gjs process with a
      native code debugger like GDB.  Add "print(imports.system.addressOf(foo))"
      for an object, then take the number it prints "12345" and paste into
      gdb like:
      p (JSObject*) 12345
    * breakpoint: Wrapper for G_BREAKPOINT().  Insert a SIGTRAP which,
      if the process is under a debugger, causes a breakpoint.  Combines
      nicely with the above.
    * gc: Forces a full garbage collection.
    
    Based on a patch by Colin Walters <walters verbum org>
    
    https://bugzilla.gnome.org/show_bug.cgi?id=630412

 Makefile-modules.am |   12 ++++++-
 modules/system.c    |  100 +++++++++++++++++++++++++++++++++++++++++++++++++++
 modules/system.h    |   40 ++++++++++++++++++++
 3 files changed, 151 insertions(+), 1 deletions(-)
---
diff --git a/Makefile-modules.am b/Makefile-modules.am
index a6fbe28..ab8aa34 100644
--- a/Makefile-modules.am
+++ b/Makefile-modules.am
@@ -17,7 +17,7 @@ dist_gjsjs_DATA +=		\
 	modules/dbus.js		\
 	modules/promise.js
 
-gjsnative_LTLIBRARIES += console.la debugger.la langNative.la mainloop.la gettextNative.la dbusNative.la cairoNative.la
+gjsnative_LTLIBRARIES += console.la debugger.la langNative.la mainloop.la gettextNative.la dbusNative.la cairoNative.la system.la
 
 JS_NATIVE_MODULE_CFLAGS =	\
         $(AM_CFLAGS)		\
@@ -94,6 +94,16 @@ cairoNative_la_SOURCES =                        \
 	modules/cairo-solid-pattern.c           \
 	modules/cairo.c
 
+system_la_CFLAGS = 				\
+	$(JS_NATIVE_MODULE_CFLAGS)
+system_la_LIBADD = \
+	$(JS_NATIVE_MODULE_LIBADD)
+system_la_LDFLAGS = 				\
+	$(JS_NATIVE_MODULE_LDFLAGS)
+
+system_la_SOURCES =		\
+	modules/system.h	\
+	modules/system.c
 
 console_la_CFLAGS = 				\
 	$(JS_NATIVE_MODULE_CFLAGS)
diff --git a/modules/system.c b/modules/system.c
new file mode 100644
index 0000000..5a19929
--- /dev/null
+++ b/modules/system.c
@@ -0,0 +1,100 @@
+/* -*- mode: C; c-basic-offset: 4; indent-tabs-mode: nil; -*- */
+/*
+ * Copyright (c) 2008  litl, LLC
+ * Copyright (c) 2012  Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <config.h>
+
+#include <gjs/gjs-module.h>
+#include <jsapi.h>
+
+#include "system.h"
+
+static JSBool
+gjs_address_of(JSContext *context,
+               uintN      argc,
+               jsval     *argv)
+{
+    JSObject *target_obj;
+    JSBool ret;
+    char *pointer_string;
+    jsval retval;
+
+    if (!gjs_parse_args(context, "addressOf", "o", argc, argv, "object", &target_obj))
+        return JS_FALSE;
+
+    pointer_string = g_strdup_printf("%p", target_obj);
+
+    ret = gjs_string_from_utf8(context, pointer_string, -1, &retval);
+    if (ret)
+        JS_SET_RVAL(context, vp, retval);
+
+    return ret;
+}
+
+static JSBool
+gjs_breakpoint(JSContext *context,
+               uintN      argc,
+               jsval     *argv)
+{
+    if (!gjs_parse_args(context, "breakpoint", "", argc, argv))
+        return JS_FALSE;
+    G_BREAKPOINT();
+    return JS_TRUE;
+}
+
+static JSBool
+gjs_gc(JSContext *context,
+       uintN      argc,
+       jsval     *argv)
+{
+    if (!gjs_parse_args(context, "gc", "", argc, argv))
+        return JS_FALSE;
+    JS_GC(context);
+    return JS_TRUE;
+}
+JSBool
+gjs_js_define_system_stuff(JSContext *context,
+                           JSObject  *module)
+{
+    if (!JS_DefineFunction(context, module,
+                           "addressOf",
+                           (JSNative) gjs_address_of,
+                           1, GJS_MODULE_PROP_FLAGS))
+        return JS_FALSE;
+
+    if (!JS_DefineFunction(context, module,
+                           "breakpoint",
+                           (JSNative) gjs_breakpoint,
+                           0, GJS_MODULE_PROP_FLAGS))
+        return JS_FALSE;
+
+    if (!JS_DefineFunction(context, module,
+                           "gc",
+                           (JSNative) gjs_gc,
+                           0, GJS_MODULE_PROP_FLAGS))
+        return JS_FALSE;
+
+    return JS_TRUE;
+}
+
+GJS_REGISTER_NATIVE_MODULE("system", gjs_js_define_system_stuff)
diff --git a/modules/system.h b/modules/system.h
new file mode 100644
index 0000000..561cac0
--- /dev/null
+++ b/modules/system.h
@@ -0,0 +1,40 @@
+/* -*- mode: C; c-basic-offset: 4; indent-tabs-mode: nil; -*- */
+/*
+ * Copyright (c) 2008  litl, LLC
+ * Copyright (c) 2012  Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef __GJS_SYSTEM_H__
+#define __GJS_SYSTEM_H__
+
+#include <config.h>
+#include <glib.h>
+
+#include <jsapi.h>
+
+G_BEGIN_DECLS
+
+JSBool        gjs_js_define_system_stuff     (JSContext      *context,
+                                              JSObject       *in_object);
+
+G_END_DECLS
+
+#endif  /* __GJS_SYSTEM_H__ */