Allow pipe + redirect in task/run stanzas, exec() in /bin/sh

This patch extends the capabilities of task and run .conf stanzas by
enabling pipes and redirects.

Example:

    task [s] echo "foo" | cat >/tmp/bar
    run  [s] echo "$HOME" >/tmp/secret

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/exec.c

@@ -213,6 +213,27 @@ int run_interactive(char *cmd, char *fmt, ...)
 	return status;
 }
 
+int exec_runtask(char *cmd, char *args[])
+{
+	size_t i;
+	char buf[1024] = "";
+	char *argv[4] = {
+		"sh",
+		"-c",
+		buf,
+		NULL
+	};
+
+	for (i = 0; args[i]; i++) {
+		strlcat(buf, args[i], sizeof(buf));
+		if (args[i + 1])
+			strlcat(buf, " ", sizeof(buf));
+	}
+	logit(LOG_DEBUG, "Calling %s %s", _PATH_BSHELL, buf);
+
+	return execve(_PATH_BSHELL, argv, __environ);
+}
+
 static void prepare_tty(char *tty, char *procname, int console)
 {
 	/* Reset signal handlers that were set by the parent process */

src/helpers.h

@@ -63,6 +63,7 @@ void    set_hostname    (char **hostname);
 int     complete        (char *cmd, int pid);
 int     run             (char *cmd);
 int     run_interactive (char *cmd, char *fmt, ...);
+int     exec_runtask    (char *cmd, char *args[]);
 pid_t   run_getty       (char *tty, char *speed, char *term, int noclear, int nowait, int console);
 pid_t   run_getty2      (char *tty, char *cmd, char *args[], int noclear, int nowait, int console);
 int     run_parts       (char *dir, char *cmd);

src/service.c

@@ -270,8 +270,10 @@ static int service_start(svc_t *svc)
 
 		if (svc->inetd.cmd)
 			status = svc->inetd.cmd(svc->inetd.type);
+		else if (svc->type & SVC_TYPE_RUNTASK)
+			status = exec_runtask(svc->cmd, args);
 		else
-			status = execv(svc->cmd, args); /* XXX: Maybe use execve() to be able to launch scripts? */
+			status = execv(svc->cmd, args);
 
 #ifdef INETD_ENABLED
 		if (svc_is_inetd_conn(svc)) {

src/svc.h

@@ -45,6 +45,7 @@ typedef enum {
 } svc_type_t;
 
 #define SVC_TYPE_ANY          (-1)
+#define SVC_TYPE_RUNTASK      (6)
 
 typedef enum {
 	SVC_HALTED_STATE = 0,	/* Not allowed in runlevel, or not enabled. */