+#define SUBST_CHAR '@'
+#define SUBST_STR "@"
+
+static char *instanciate_string(char *arg, const char *port, const char *token)
+{
+ char *resu, *it, *wr;
+ int chg, dif;
+
+ /* get the changes */
+ chg = 0;
+ dif = 0;
+ it = strchrnul(arg, SUBST_CHAR);
+ while (*it) {
+ switch(*++it) {
+ case 'p': chg++; dif += (int)strlen(port) - 2; break;
+ case 't': chg++; dif += (int)strlen(token) - 2; break;
+ case SUBST_CHAR: it++; chg++; dif--; break;
+ default: break;
+ }
+ it = strchrnul(it, SUBST_CHAR);
+ }
+
+ /* return arg when no change */
+ if (!chg)
+ return arg;
+
+ /* allocates the result */
+ resu = malloc((it - arg) + dif + 1);
+ if (!resu) {
+ ERROR("out of memory");
+ return NULL;
+ }
+
+ /* instanciate the arguments */
+ wr = resu;
+ for (;;) {
+ it = strchrnul(arg, SUBST_CHAR);
+ wr = mempcpy(wr, arg, it - arg);
+ if (!*it)
+ break;
+ switch(*++it) {
+ case 'p': wr = stpcpy(wr, port); break;
+ case 't': wr = stpcpy(wr, token); break;
+ default: *wr++ = SUBST_CHAR;
+ case SUBST_CHAR: *wr++ = *it;
+ }
+ arg = ++it;
+ }
+
+ *wr = 0;
+ return resu;
+}
+
+static int instanciate_environ(const char *port, const char *token)
+{
+ extern char **environ;
+ char *repl;
+ int i;
+
+ /* instanciate the environment */
+ for (i = 0 ; environ[i] ; i++) {
+ repl = instanciate_string(environ[i], port, token);
+ if (!repl)
+ return -1;
+ environ[i] = repl;
+ }
+ return 0;
+}
+
+static int instanciate_command_args(const char *port, const char *token)
+{
+ char *repl;
+ int i;
+
+ /* instanciate the arguments */
+ for (i = 0 ; config->exec[i] ; i++) {
+ repl = instanciate_string(config->exec[i], port, token);
+ if (!repl)
+ return -1;
+ config->exec[i] = repl;
+ }
+ return 0;
+}
+
+static int execute_command()
+{
+ struct sigaction siga;
+ char port[20];
+ int rc;
+
+ /* check whether a command is to execute or not */
+ if (!config->exec || !config->exec[0])
+ return 0;
+
+ if (SELF_PGROUP)
+ setpgid(0, 0);
+
+ /* install signal handler */
+ memset(&siga, 0, sizeof siga);
+ siga.sa_sigaction = on_sigchld;
+ siga.sa_flags = SA_SIGINFO;
+ sigaction(SIGCHLD, &siga, NULL);
+
+ /* fork now */
+ childpid = fork();
+ if (childpid)
+ return 0;
+
+ /* compute the string for port */
+ if (config->httpdPort)
+ rc = snprintf(port, sizeof port, "%d", config->httpdPort);
+ else
+ rc = snprintf(port, sizeof port, "%cp", SUBST_CHAR);
+ if (rc < 0 || rc >= (int)(sizeof port)) {
+ ERROR("port->txt failed");
+ }
+ else {
+ /* instanciate arguments and environment */
+ if (instanciate_command_args(port, config->token) >= 0
+ && instanciate_environ(port, config->token) >= 0) {
+ /* run */
+ if (!SELF_PGROUP)
+ setpgid(0, 0);
+ execv(config->exec[0], config->exec);
+ ERROR("can't launch %s: %m", config->exec[0]);
+ }
+ }
+ exit(1);
+ return -1;
+}
+
+/*---------------------------------------------------------
+ | job for starting the daemon
+ +--------------------------------------------------------- */
+
+static void start()
+{
+ struct afb_hsrv *hsrv;