[PATCH 3/3] Fix commit-msg hook to allow editing

[Wincent Colaiuta <win@wincent.com>]

The old git-commit.sh script allowed the commit-msg hook to not only
prevent a commit from proceding, but also to edit the commit message
on the fly and allow it to proceed. So here we teach builtin-commit
to do the same.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
---
 builtin-commit.c |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/builtin-commit.c b/builtin-commit.c
index df9377e..a6223d2 100644
--- a/builtin-commit.c
+++ b/builtin-commit.c
@@ -787,14 +787,18 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		const char *env[2] = { index, NULL };
 		snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 		launch_editor(git_path(commit_editmsg), &sb, env);
-	} else if (strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
-		rollback_index_files();
-		die("could not read commit message");
 	}
-	if (!no_verify &&
-	    run_hook(index_file, "commit-msg", git_path(commit_editmsg))) {
+	if (!no_verify) {
+		if (run_hook(index_file, "commit-msg", git_path(commit_editmsg))) {
+			rollback_index_files();
+			exit(1);
+		}
+		strbuf_setlen(&sb, header_len);
+	}
+	if ((no_edit || !no_verify) &&
+	    strbuf_read_file(&sb, git_path(commit_editmsg), 0) < 0) {
 		rollback_index_files();
-		exit(1);
+		die("could not read commit message");
 	}
 
 	/* Truncate the message just before the diff, if any. */
-- 
1.5.3.7.1115.gaa595