perf ui/gtk: Introduce struct perf_gtk_context

The struct perf_gtk_context is for tracking current state of GTK window
and/or other things. This is a preparation of next changes.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338265382-6872-5-git-send-email-namhyung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/ui/gtk/browser.c b/tools/perf/ui/gtk/browser.c
index 0656c38..33ab1ae 100644
--- a/tools/perf/ui/gtk/browser.c
+++ b/tools/perf/ui/gtk/browser.c
@@ -11,8 +11,8 @@
 
 static void perf_gtk__signal(int sig)
 {
+	perf_gtk__exit(false);
 	psignal(sig, "perf");
-	gtk_main_quit();
 }
 
 static void perf_gtk__resize_window(GtkWidget *window)
@@ -143,6 +143,10 @@
 
 	g_signal_connect(window, "delete_event", gtk_main_quit, NULL);
 
+	pgctx = perf_gtk__activate_context(window);
+	if (!pgctx)
+		return -1;
+
 	notebook = gtk_notebook_new();
 
 	list_for_each_entry(pos, &evlist->entries, node) {
@@ -174,5 +178,7 @@
 
 	gtk_main();
 
+	perf_gtk__deactivate_context(&pgctx);
+
 	return 0;
 }
diff --git a/tools/perf/ui/gtk/gtk.h b/tools/perf/ui/gtk/gtk.h
index 75177ee..34fbca6 100644
--- a/tools/perf/ui/gtk/gtk.h
+++ b/tools/perf/ui/gtk/gtk.h
@@ -1,8 +1,25 @@
 #ifndef _PERF_GTK_H_
 #define _PERF_GTK_H_ 1
 
+#include <stdbool.h>
+
 #pragma GCC diagnostic ignored "-Wstrict-prototypes"
 #include <gtk/gtk.h>
 #pragma GCC diagnostic error "-Wstrict-prototypes"
 
+
+struct perf_gtk_context {
+	GtkWidget *main_window;
+};
+
+extern struct perf_gtk_context *pgctx;
+
+static inline bool perf_gtk__is_active_context(struct perf_gtk_context *ctx)
+{
+	return ctx && ctx->main_window;
+}
+
+struct perf_gtk_context *perf_gtk__activate_context(GtkWidget *window);
+int perf_gtk__deactivate_context(struct perf_gtk_context **ctx);
+
 #endif /* _PERF_GTK_H_ */
diff --git a/tools/perf/ui/gtk/util.c b/tools/perf/ui/gtk/util.c
index a727fe3..6fe13fd 100644
--- a/tools/perf/ui/gtk/util.c
+++ b/tools/perf/ui/gtk/util.c
@@ -3,6 +3,29 @@
 #include "gtk.h"
 
 
+struct perf_gtk_context *pgctx;
+
+struct perf_gtk_context *perf_gtk__activate_context(GtkWidget *window)
+{
+	struct perf_gtk_context *ctx;
+
+	ctx = malloc(sizeof(*pgctx));
+	if (ctx)
+		ctx->main_window = window;
+
+	return ctx;
+}
+
+int perf_gtk__deactivate_context(struct perf_gtk_context **ctx)
+{
+	if (!perf_gtk__is_active_context(*ctx))
+		return -1;
+
+	free(*ctx);
+	*ctx = NULL;
+	return 0;
+}
+
 /*
  * FIXME: Functions below should be implemented properly.
  *        For now, just add stubs for NO_NEWT=1 build.