Initial support for gdb python macros

This includes support for gobject pointer pretty printing and
signal frame compression in backtraces.

https://bugzilla.gnome.org/show_bug.cgi?id=595619

glib/Makefile.am

@@ -70,6 +70,7 @@ EXTRA_DIST += 			\
 	gregex.c		\
 	gregex.h		\
 	win_iconv.c		\
+	libglib-gdb.py.in	\
 	$(MIRRORING_TAB_SOURCE)
 
 # These may be in the builddir too
@@ -365,8 +366,18 @@ dist-hook: $(BUILT_EXTRA_DIST)
 	  if test -f $$f; then d=.; else d=$(srcdir); fi; \
 	  cp $$d/$$f $(distdir) || exit 1; done
 
+# install gdb scripts
+gdbdir = $(datadir)/glib-2.0/gdb
+gdb_SCRIPTS = glib.py
+
+libglib-gdb.py: libglib-gdb.py.in
+	sed -e "s|\@datadir\@|$(datadir)|" libglib-gdb.py.in > libglib-gdb.py
+
+
+install-data-hook: libglib-gdb.py
+	mkdir -p $(DESTDIR)$(datadir)/gdb/auto-load${libdir}
+	$(INSTALL) libglib-gdb.py $(DESTDIR)$(datadir)/gdb/auto-load${libdir}/libglib-2.0.so.0.$(LT_CURRENT).0-gdb.py
 if HAVE_GLIB_RUNTIME_LIBDIR
-install-data-hook:
 	mkdir -p $(DESTDIR)$(libdir)/$(GLIB_RUNTIME_LIBDIR)
 	mv $(DESTDIR)$(libdir)/libglib-2.0.so.0 $(DESTDIR)$(libdir)/$(GLIB_RUNTIME_LIBDIR)
 	mv $(DESTDIR)$(libdir)/libglib-2.0.so.0.$(LT_CURRENT).0 $(DESTDIR)$(libdir)/$(GLIB_RUNTIME_LIBDIR)

glib/glib.py

@@ -0,0 +1,27 @@
+import gdb
+
+# This is not quite right, as local vars may override symname
+def read_global_var (symname):
+    return gdb.selected_frame().read_var(symname)
+
+def g_quark_to_string (quark):
+    if quark == None:
+        return None
+    quark = long(quark)
+    if quark == 0:
+        return None
+    val = read_global_var ("g_quarks")
+    max_q = long(read_global_var ("g_quark_seq_id"))
+    if quark < max_q:
+        return val[quark].string()
+    return None
+
+def pretty_printer_lookup (val):
+    # None yet, want things like hash table and list
+    return None
+
+def register (obj):
+    if obj == None:
+        obj = gdb
+
+    obj.pretty_printers.append(pretty_printer_lookup)

glib/libglib-gdb.py.in

@@ -0,0 +1,10 @@
+import sys
+import gdb
+
+# Update module path.
+dir = '@datadir@/glib-2.0/gdb'
+if not dir in sys.path:
+    sys.path.insert(0, dir)
+
+from glib import register
+register (gdb.current_objfile ())