run-command: convert simple callsites to use_shell

Now that we have the use_shell feature, these callsites can
all be converted with small changes.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

convert.c

@@ -249,10 +249,11 @@ static int filter_buffer(int fd, void *data)
 	struct child_process child_process;
 	struct filter_params *params = (struct filter_params *)data;
 	int write_err, status;
-	const char *argv[] = { "sh", "-c", params->cmd, NULL };
+	const char *argv[] = { params->cmd, NULL };
 
 	memset(&child_process, 0, sizeof(child_process));
 	child_process.argv = argv;
+	child_process.use_shell = 1;
 	child_process.in = -1;
 	child_process.out = fd;
 

imap-send.c

@@ -965,17 +965,13 @@ static struct store *imap_open_store(struct imap_server_conf *srvc)
 	/* open connection to IMAP server */
 
 	if (srvc->tunnel) {
-		const char *argv[4];
+		const char *argv[] = { srvc->tunnel, NULL };
 		struct child_process tunnel = {0};
 
 		imap_info("Starting tunnel '%s'... ", srvc->tunnel);
 
-		argv[0] = "sh";
-		argv[1] = "-c";
-		argv[2] = srvc->tunnel;
-		argv[3] = NULL;
-
 		tunnel.argv = argv;
+		tunnel.use_shell = 1;
 		tunnel.in = -1;
 		tunnel.out = -1;
 		if (start_command(&tunnel))

ll-merge.c

@@ -175,7 +175,7 @@ static int ll_ext_merge(const struct ll_merge_driver *fn,
 		{ "B", temp[2] },
 		{ NULL }
 	};
-	const char *args[] = { "sh", "-c", NULL, NULL };
+	const char *args[] = { NULL, NULL };
 	int status, fd, i;
 	struct stat st;
 
@@ -190,8 +190,8 @@ static int ll_ext_merge(const struct ll_merge_driver *fn,
 
 	strbuf_expand(&cmd, fn->cmdline, strbuf_expand_dict_cb, &dict);
 
-	args[2] = cmd.buf;
+	args[0] = cmd.buf;
-	status = run_command_v_opt(args, 0);
+	status = run_command_v_opt(args, RUN_USING_SHELL);
 	fd = open(temp[1], O_RDONLY);
 	if (fd < 0)
 		goto bad;

pager.c

@@ -28,7 +28,7 @@ static void pager_preexec(void)
 }
 #endif
 
-static const char *pager_argv[] = { "sh", "-c", NULL, NULL };
+static const char *pager_argv[] = { NULL, NULL };
 static struct child_process pager_process;
 
 static void wait_for_pager(void)
@@ -81,7 +81,8 @@ void setup_pager(void)
 	spawned_pager = 1; /* means we are emitting to terminal */
 
 	/* spawn the pager */
-	pager_argv[2] = pager;
+	pager_argv[0] = pager;
+	pager_process.use_shell = 1;
 	pager_process.argv = pager_argv;
 	pager_process.in = -1;
 	if (!getenv("LESS")) {