perf newt: Properly restore the screen when error exiting

Show an OK message box with the last message sent via pr_err,
etc.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1269274229-20442-1-git-send-email-acme@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

tools/perf/perf.c

@@ -264,11 +264,11 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 	set_debugfs_path();
 
 	status = p->fn(argc, argv, prefix);
+	exit_browser(status);
+
 	if (status)
 		return status & 0xff;
 
-	exit_browser();
-
 	/* Somebody closed stdout? */
 	if (fstat(fileno(stdout), &st))
 		return 0;

tools/perf/util/cache.h

@@ -77,10 +77,10 @@ static inline void setup_browser(void)
 {
 	setup_pager();
 }
-static inline void exit_browser(void) {}
+static inline void exit_browser(bool wait_for_ok __used) {}
 #else
 void setup_browser(void);
-void exit_browser(void);
+void exit_browser(bool wait_for_ok);
 #endif
 
 extern const char *editor_program;

tools/perf/util/newt.c

@@ -170,18 +170,20 @@ void perf_session__browse_hists(struct rb_root *hists, u64 session_total,
 	newtFormDestroy(form);
 }
 
+static char browser__last_msg[1024];
+
 int browser__show_help(const char *format, va_list ap)
 {
 	int ret;
 	static int backlog;
-	static char msg[1024];
 
-        ret = vsnprintf(msg + backlog, sizeof(msg) - backlog, format, ap);
+        ret = vsnprintf(browser__last_msg + backlog,
+			sizeof(browser__last_msg) - backlog, format, ap);
 	backlog += ret;
 
-	if (msg[backlog - 1] == '\n') {
+	if (browser__last_msg[backlog - 1] == '\n') {
 		newtPopHelpLine();
-		newtPushHelpLine(msg);
+		newtPushHelpLine(browser__last_msg);
 		newtRefresh();
 		backlog = 0;
 	}
@@ -200,8 +202,13 @@ void setup_browser(void)
 	newtPushHelpLine(" ");
 }
 
-void exit_browser(void)
+void exit_browser(bool wait_for_ok)
 {
-	if (use_browser)
+	if (use_browser) {
+		if (wait_for_ok) {
+			char title[] = "Fatal Error", ok[] = "Ok";
+			newtWinMessage(title, ok, browser__last_msg);
+		}
 		newtFinished();
+	}
 }