Add run_command_v_opt_cd: chdir into a directory before exec

It can make code simplier (no need to preserve cwd) and safer
(no chance the cwd of the current process is accidentally forgotten).

Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 22 insertions, 5 deletions

diff --git a/run-command.c b/run-command.c
index eff523e191..043b5701a1 100644
--- a/run-command.c
+++ b/run-command.c
@@ -73,6 +73,9 @@ int start_command(struct child_process *cmd)
 			close(cmd->out);
 		}
 
+		if (cmd->dir && chdir(cmd->dir))
+			die("exec %s: cd to %s failed (%s)", cmd->argv[0],
+			    cmd->dir, strerror(errno));
 		if (cmd->git_cmd) {
 			execv_git_cmd(cmd->argv);
 		} else {
@@ -133,13 +136,27 @@ int run_command(struct child_process *cmd)
 	return finish_command(cmd);
 }
 
+static void prepare_run_command_v_opt(struct child_process *cmd,
+				      const char **argv, int opt)
+{
+	memset(cmd, 0, sizeof(*cmd));
+	cmd->argv = argv;
+	cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
+	cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
+	cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
+}
+
 int run_command_v_opt(const char **argv, int opt)
 {
 	struct child_process cmd;
-	memset(&cmd, 0, sizeof(cmd));
-	cmd.argv = argv;
-	cmd.no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
-	cmd.git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
-	cmd.stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
+	prepare_run_command_v_opt(&cmd, argv, opt);
+	return run_command(&cmd);
+}
+
+int run_command_v_opt_cd(const char **argv, int opt, const char *dir)
+{
+	struct child_process cmd;
+	prepare_run_command_v_opt(&cmd, argv, opt);
+	cmd.dir = dir;
 	return run_command(&cmd);
 }