From 8cf71ddd8d5f852b6b8905537cc37cb72efb24fb Mon Sep 17 00:00:00 2001
From: Thomas Goyne <plorkyeran@aegisub.org>
Date: Wed, 18 Jan 2012 20:08:16 +0000
Subject: [PATCH] Fix crash when seeking to previous keyframe with no keyframes
 loaded

Originally committed to SVN as r6305.
---
 aegisub/src/command/video.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/aegisub/src/command/video.cpp b/aegisub/src/command/video.cpp
index 108c08ec5..0fccea4cc 100644
--- a/aegisub/src/command/video.cpp
+++ b/aegisub/src/command/video.cpp
@@ -451,9 +451,14 @@ struct video_frame_prev_keyframe : public validator_video_loaded {
 	STR_HELP("Seek to the previous keyframe.")
 
 	void operator()(agi::Context *c) {
-		int frame = c->videoController->GetFrameN();
 		std::vector<int> const& kf = c->videoController->GetKeyFrames();
-		std::vector<int>::const_iterator pos = lower_bound(kf.begin(), kf.end(), frame);
+		if (kf.empty()) {
+			c->videoController->JumpToFrame(0);
+			return;
+		}
+
+		std::vector<int>::const_iterator pos =
+			lower_bound(kf.begin(), kf.end(), c->videoController->GetFrameN());
 
 		if (pos != kf.begin())
 			--pos;