From 74d7c14dd4a3ed9c5def0dc3c1aeede399ddc5c5 Mon Sep 17 00:00:00 2001
From: zeripath <art27@cantab.net>
Date: Mon, 11 Mar 2019 07:11:10 +0000
Subject: [PATCH] Fix panic on signed empty commit message
 (go-gitea/gitea#6292) (#149)

* Fix panic on signed empty commit message (go-gitea/gitea#6292)
---
 repo_commit.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/repo_commit.go b/repo_commit.go
index 0d2d5e4..2d9f5bd 100644
--- a/repo_commit.go
+++ b/repo_commit.go
@@ -101,7 +101,11 @@ l:
 				sig, err := newGPGSignatureFromCommitline(data, (nextline+1)+sigindex, true)
 				if err == nil && sig != nil {
 					// remove signature from commit message
-					cm = cm[:sigindex-1]
+					if sigindex == 0 {
+						cm = ""
+					} else {
+						cm = cm[:sigindex-1]
+					}
 					commit.Signature = sig
 				}
 			}