Add ability to specify environment extension to run_command

There is no way to specify and override for the environment:
there'd be no user for it yet.

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

run-command.c

@@ -76,6 +76,10 @@ int start_command(struct child_process *cmd)
 		if (cmd->dir && chdir(cmd->dir))
 			die("exec %s: cd to %s failed (%s)", cmd->argv[0],
 			    cmd->dir, strerror(errno));
+		if (cmd->env) {
+			for (; *cmd->env; cmd->env++)
+				putenv((char*)*cmd->env);
+		}
 		if (cmd->git_cmd) {
 			execv_git_cmd(cmd->argv);
 		} else {
@@ -137,7 +141,8 @@ int run_command(struct child_process *cmd)
 }
 
 static void prepare_run_command_v_opt(struct child_process *cmd,
-				      const char **argv, int opt)
+				      const char **argv,
+				      int opt)
 {
 	memset(cmd, 0, sizeof(*cmd));
 	cmd->argv = argv;
@@ -160,3 +165,12 @@ int run_command_v_opt_cd(const char **argv, int opt, const char *dir)
 	cmd.dir = dir;
 	return run_command(&cmd);
 }
+
+int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
+{
+	struct child_process cmd;
+	prepare_run_command_v_opt(&cmd, argv, opt);
+	cmd.dir = dir;
+	cmd.env = env;
+	return run_command(&cmd);
+}

run-command.h

@@ -17,6 +17,7 @@ struct child_process {
 	int in;
 	int out;
 	const char *dir;
+	const char *const *env;
 	unsigned close_in:1;
 	unsigned close_out:1;
 	unsigned no_stdin:1;
@@ -34,5 +35,6 @@ int run_command(struct child_process *);
 #define RUN_COMMAND_STDOUT_TO_STDERR 4
 int run_command_v_opt(const char **argv, int opt);
 int run_command_v_opt_cd(const char **argv, int opt, const char *dir);
+int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env);
 
 #endif