revert: refactor code into a do_pick_commit() function

This is needed because we are going to make it possible
to cherry-pick many commits instead of just one in the following
commits. And we will be able to do that by just calling
do_pick_commit() once for each commit to cherry-pick.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/revert.c

@@ -365,7 +365,7 @@ static void do_recursive_merge(struct commit *base, struct commit *next,
 	fprintf(stderr, "Finished one %s.\n", me);
 }
 
-static int revert_or_cherry_pick(int argc, const char **argv)
+static int do_pick_commit(void)
 {
 	unsigned char head[20];
 	struct commit *base, *next, *parent;
@@ -374,24 +374,6 @@ static int revert_or_cherry_pick(int argc, const char **argv)
 	char *defmsg = NULL;
 	struct strbuf msgbuf = STRBUF_INIT;
 
-	git_config(git_default_config, NULL);
-	me = action == REVERT ? "revert" : "cherry-pick";
-	setenv(GIT_REFLOG_ACTION, me, 0);
-	parse_args(argc, argv);
-
-	if (allow_ff) {
-		if (signoff)
-			die("cherry-pick --ff cannot be used with --signoff");
-		if (no_commit)
-			die("cherry-pick --ff cannot be used with --no-commit");
-		if (no_replay)
-			die("cherry-pick --ff cannot be used with -x");
-		if (edit)
-			die("cherry-pick --ff cannot be used with --edit");
-	}
-
-	if (read_cache() < 0)
-		die("git %s: failed to read the index", me);
 	if (no_commit) {
 		/*
 		 * We do not intend to commit immediately.  We just want to
@@ -545,6 +527,30 @@ static int revert_or_cherry_pick(int argc, const char **argv)
 	return 0;
 }
 
+static int revert_or_cherry_pick(int argc, const char **argv)
+{
+	git_config(git_default_config, NULL);
+	me = action == REVERT ? "revert" : "cherry-pick";
+	setenv(GIT_REFLOG_ACTION, me, 0);
+	parse_args(argc, argv);
+
+	if (allow_ff) {
+		if (signoff)
+			die("cherry-pick --ff cannot be used with --signoff");
+		if (no_commit)
+			die("cherry-pick --ff cannot be used with --no-commit");
+		if (no_replay)
+			die("cherry-pick --ff cannot be used with -x");
+		if (edit)
+			die("cherry-pick --ff cannot be used with --edit");
+	}
+
+	if (read_cache() < 0)
+		die("git %s: failed to read the index", me);
+
+	return do_pick_commit();
+}
+
 int cmd_revert(int argc, const char **argv, const char *prefix)
 {
 	if (isatty(0))