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1 /***************************************************************************
2  *   Copyright (C) 2005 by Dominic Rath                                    *
3  *   Dominic.Rath@gmx.de                                                   *
4  *                                                                         *
5  *   Copyright (C) 2007-2010 Ã˜yvind Harboe                                 *
6  *   oyvind.harboe@zylin.com                                               *
7  *                                                                         *
8  *   Copyright (C) 2008 by Spencer Oliver                                  *
9  *   spen@spen-soft.co.uk                                                  *
10  *                                                                         *
11  *   This program is free software; you can redistribute it and/or modify  *
12  *   it under the terms of the GNU General Public License as published by  *
13  *   the Free Software Foundation; either version 2 of the License, or     *
14  *   (at your option) any later version.                                   *
15  *                                                                         *
16  *   This program is distributed in the hope that it will be useful,       *
17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
19  *   GNU General Public License for more details.                          *
20  *                                                                         *
21  *   You should have received a copy of the GNU General Public License     *
22  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
23  ***************************************************************************/
24
25 #ifdef HAVE_CONFIG_H
26 #include "config.h"
27 #endif
28
29 #include "server.h"
30 #include <target/target.h>
31 #include <target/target_request.h>
32 #include <target/openrisc/jsp_server.h>
33 #include "openocd.h"
34 #include "tcl_server.h"
35 #include "telnet_server.h"
36
37 #include <signal.h>
38
39 #ifdef HAVE_NETDB_H
40 #include <netdb.h>
41 #endif
42
43 #ifndef _WIN32
44 #include <netinet/tcp.h>
45 #endif
46
47 static struct service *services;
48
49 /* shutdown_openocd == 1: exit the main event loop, and quit the
50  * debugger; 2: quit with non-zero return code */
51 static int shutdown_openocd;
52
53 /* store received signal to exit application by killing ourselves */
54 static int last_signal;
55
56 /* set the polling period to 100ms */
57 static int polling_period = 100;
58
59 /* address by name on which to listen for incoming TCP/IP connections */
60 static char *bindto_name;
61
62 static int add_connection(struct service *service, struct command_context *cmd_ctx)
63 {
64         socklen_t address_size;
65         struct connection *c, **p;
66         int retval;
67         int flag = 1;
68
69         c = malloc(sizeof(struct connection));
70         c->fd = -1;
71         c->fd_out = -1;
72         memset(&c->sin, 0, sizeof(c->sin));
73         c->cmd_ctx = copy_command_context(cmd_ctx);
74         c->service = service;
75         c->input_pending = 0;
76         c->priv = NULL;
77         c->next = NULL;
78
79         if (service->type == CONNECTION_TCP) {
80                 address_size = sizeof(c->sin);
81
82                 c->fd = accept(service->fd, (struct sockaddr *)&service->sin, &address_size);
83                 c->fd_out = c->fd;
84
85                 /* This increases performance dramatically for e.g. GDB load which
86                  * does not have a sliding window protocol.
87                  *
88                  * Ignore errors from this fn as it probably just means less performance
89                  */
90                 setsockopt(c->fd,       /* socket affected */
91                         IPPROTO_TCP,                    /* set option at TCP level */
92                         TCP_NODELAY,                    /* name of option */
93                         (char *)&flag,                  /* the cast is historical cruft */
94                         sizeof(int));                   /* length of option value */
95
96                 LOG_INFO("accepting '%s' connection on tcp/%s", service->name, service->port);
97                 retval = service->new_connection(c);
98                 if (retval != ERROR_OK) {
99                         close_socket(c->fd);
100                         LOG_ERROR("attempted '%s' connection rejected", service->name);
101                         command_done(c->cmd_ctx);
102                         free(c);
103                         return retval;
104                 }
105         } else if (service->type == CONNECTION_STDINOUT) {
106                 c->fd = service->fd;
107                 c->fd_out = fileno(stdout);
108
109 #ifdef _WIN32
110                 /* we are using stdin/out so ignore ctrl-c under windoze */
111                 SetConsoleCtrlHandler(NULL, TRUE);
112 #endif
113
114                 /* do not check for new connections again on stdin */
115                 service->fd = -1;
116
117                 LOG_INFO("accepting '%s' connection from pipe", service->name);
118                 retval = service->new_connection(c);
119                 if (retval != ERROR_OK) {
120                         LOG_ERROR("attempted '%s' connection rejected", service->name);
121                         command_done(c->cmd_ctx);
122                         free(c);
123                         return retval;
124                 }
125         } else if (service->type == CONNECTION_PIPE) {
126                 c->fd = service->fd;
127                 /* do not check for new connections again on stdin */
128                 service->fd = -1;
129
130                 char *out_file = alloc_printf("%so", service->port);
131                 c->fd_out = open(out_file, O_WRONLY);
132                 free(out_file);
133                 if (c->fd_out == -1) {
134                         LOG_ERROR("could not open %s", service->port);
135                         command_done(c->cmd_ctx);
136                         free(c);
137                         return ERROR_FAIL;
138                 }
139
140                 LOG_INFO("accepting '%s' connection from pipe %s", service->name, service->port);
141                 retval = service->new_connection(c);
142                 if (retval != ERROR_OK) {
143                         LOG_ERROR("attempted '%s' connection rejected", service->name);
144                         command_done(c->cmd_ctx);
145                         free(c);
146                         return retval;
147                 }
148         }
149
150         /* add to the end of linked list */
151         for (p = &service->connections; *p; p = &(*p)->next)
152                 ;
153         *p = c;
154
155         if (service->max_connections != CONNECTION_LIMIT_UNLIMITED)
156                 service->max_connections--;
157
158         return ERROR_OK;
159 }
160
161 static int remove_connection(struct service *service, struct connection *connection)
162 {
163         struct connection **p = &service->connections;
164         struct connection *c;
165
166         /* find connection */
167         while ((c = *p)) {
168                 if (c->fd == connection->fd) {
169                         service->connection_closed(c);
170                         if (service->type == CONNECTION_TCP)
171                                 close_socket(c->fd);
172                         else if (service->type == CONNECTION_PIPE) {
173                                 /* The service will listen to the pipe again */
174                                 c->service->fd = c->fd;
175                         }
176
177                         command_done(c->cmd_ctx);
178
179                         /* delete connection */
180                         *p = c->next;
181                         free(c);
182
183                         if (service->max_connections != CONNECTION_LIMIT_UNLIMITED)
184                                 service->max_connections++;
185
186                         break;
187                 }
188
189                 /* redirect p to next list pointer */
190                 p = &(*p)->next;
191         }
192
193         return ERROR_OK;
194 }
195
196 static void free_service(struct service *c)
197 {
198         free(c->name);
199         free(c->port);
200         free(c);
201 }
202
203 int add_service(char *name,
204         const char *port,
205         int max_connections,
206         new_connection_handler_t new_connection_handler,
207         input_handler_t input_handler,
208         connection_closed_handler_t connection_closed_handler,
209         void *priv)
210 {
211         struct service *c, **p;
212         struct hostent *hp;
213         int so_reuseaddr_option = 1;
214
215         c = malloc(sizeof(struct service));
216
217         c->name = strdup(name);
218         c->port = strdup(port);
219         c->max_connections = 1; /* Only TCP/IP ports can support more than one connection */
220         c->fd = -1;
221         c->connections = NULL;
222         c->new_connection = new_connection_handler;
223         c->input = input_handler;
224         c->connection_closed = connection_closed_handler;
225         c->priv = priv;
226         c->next = NULL;
227         long portnumber;
228         if (strcmp(c->port, "pipe") == 0)
229                 c->type = CONNECTION_STDINOUT;
230         else {
231                 char *end;
232                 portnumber = strtol(c->port, &end, 0);
233                 if (!*end && (parse_long(c->port, &portnumber) == ERROR_OK)) {
234                         c->portnumber = portnumber;
235                         c->type = CONNECTION_TCP;
236                 } else
237                         c->type = CONNECTION_PIPE;
238         }
239
240         if (c->type == CONNECTION_TCP) {
241                 c->max_connections = max_connections;
242
243                 c->fd = socket(AF_INET, SOCK_STREAM, 0);
244                 if (c->fd == -1) {
245                         LOG_ERROR("error creating socket: %s", strerror(errno));
246                         free_service(c);
247                         return ERROR_FAIL;
248                 }
249
250                 setsockopt(c->fd,
251                         SOL_SOCKET,
252                         SO_REUSEADDR,
253                         (void *)&so_reuseaddr_option,
254                         sizeof(int));
255
256                 socket_nonblock(c->fd);
257
258                 memset(&c->sin, 0, sizeof(c->sin));
259                 c->sin.sin_family = AF_INET;
260
261                 if (bindto_name == NULL)
262                         c->sin.sin_addr.s_addr = INADDR_ANY;
263                 else {
264                         hp = gethostbyname(bindto_name);
265                         if (hp == NULL) {
266                                 LOG_ERROR("couldn't resolve bindto address: %s", bindto_name);
267                                 close_socket(c->fd);
268                                 free_service(c);
269                                 return ERROR_FAIL;
270                         }
271                         memcpy(&c->sin.sin_addr, hp->h_addr_list[0], hp->h_length);
272                 }
273                 c->sin.sin_port = htons(c->portnumber);
274
275                 if (bind(c->fd, (struct sockaddr *)&c->sin, sizeof(c->sin)) == -1) {
276                         LOG_ERROR("couldn't bind %s to socket on port %d: %s", name, c->portnumber, strerror(errno));
277                         close_socket(c->fd);
278                         free_service(c);
279                         return ERROR_FAIL;
280                 }
281
282 #ifndef _WIN32
283                 int segsize = 65536;
284                 setsockopt(c->fd, IPPROTO_TCP, TCP_MAXSEG,  &segsize, sizeof(int));
285 #endif
286                 int window_size = 128 * 1024;
287
288                 /* These setsockopt()s must happen before the listen() */
289
290                 setsockopt(c->fd, SOL_SOCKET, SO_SNDBUF,
291                         (char *)&window_size, sizeof(window_size));
292                 setsockopt(c->fd, SOL_SOCKET, SO_RCVBUF,
293                         (char *)&window_size, sizeof(window_size));
294
295                 if (listen(c->fd, 1) == -1) {
296                         LOG_ERROR("couldn't listen on socket: %s", strerror(errno));
297                         close_socket(c->fd);
298                         free_service(c);
299                         return ERROR_FAIL;
300                 }
301
302                 struct sockaddr_in addr_in;
303                 addr_in.sin_port = 0;
304                 socklen_t addr_in_size = sizeof(addr_in);
305                 if (getsockname(c->fd, (struct sockaddr *)&addr_in, &addr_in_size) == 0)
306                         LOG_INFO("Listening on port %hu for %s connections",
307                                  ntohs(addr_in.sin_port), name);
308         } else if (c->type == CONNECTION_STDINOUT) {
309                 c->fd = fileno(stdin);
310
311 #ifdef _WIN32
312                 /* for win32 set stdin/stdout to binary mode */
313                 if (_setmode(_fileno(stdout), _O_BINARY) < 0)
314                         LOG_WARNING("cannot change stdout mode to binary");
315                 if (_setmode(_fileno(stdin), _O_BINARY) < 0)
316                         LOG_WARNING("cannot change stdin mode to binary");
317                 if (_setmode(_fileno(stderr), _O_BINARY) < 0)
318                         LOG_WARNING("cannot change stderr mode to binary");
319 #else
320                 socket_nonblock(c->fd);
321 #endif
322         } else if (c->type == CONNECTION_PIPE) {
323 #ifdef _WIN32
324                 /* we currenty do not support named pipes under win32
325                  * so exit openocd for now */
326                 LOG_ERROR("Named pipes currently not supported under this os");
327                 free_service(c);
328                 return ERROR_FAIL;
329 #else
330                 /* Pipe we're reading from */
331                 c->fd = open(c->port, O_RDONLY | O_NONBLOCK);
332                 if (c->fd == -1) {
333                         LOG_ERROR("could not open %s", c->port);
334                         free_service(c);
335                         return ERROR_FAIL;
336                 }
337 #endif
338         }
339
340         /* add to the end of linked list */
341         for (p = &services; *p; p = &(*p)->next)
342                 ;
343         *p = c;
344
345         return ERROR_OK;
346 }
347
348 static int remove_services(void)
349 {
350         struct service *c = services;
351
352         /* loop service */
353         while (c) {
354                 struct service *next = c->next;
355
356                 if (c->name)
357                         free(c->name);
358
359                 if (c->type == CONNECTION_PIPE) {
360                         if (c->fd != -1)
361                                 close(c->fd);
362                 }
363                 if (c->port)
364                         free(c->port);
365
366                 if (c->priv)
367                         free(c->priv);
368
369                 /* delete service */
370                 free(c);
371
372                 /* remember the last service for unlinking */
373                 c = next;
374         }
375
376         services = NULL;
377
378         return ERROR_OK;
379 }
380
381 int server_loop(struct command_context *command_context)
382 {
383         struct service *service;
384
385         bool poll_ok = true;
386
387         /* used in select() */
388         fd_set read_fds;
389         int fd_max;
390
391         /* used in accept() */
392         int retval;
393
394 #ifndef _WIN32
395         if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
396                 LOG_ERROR("couldn't set SIGPIPE to SIG_IGN");
397 #endif
398
399         while (!shutdown_openocd) {
400                 /* monitor sockets for activity */
401                 fd_max = 0;
402                 FD_ZERO(&read_fds);
403
404                 /* add service and connection fds to read_fds */
405                 for (service = services; service; service = service->next) {
406                         if (service->fd != -1) {
407                                 /* listen for new connections */
408                                 FD_SET(service->fd, &read_fds);
409
410                                 if (service->fd > fd_max)
411                                         fd_max = service->fd;
412                         }
413
414                         if (service->connections) {
415                                 struct connection *c;
416
417                                 for (c = service->connections; c; c = c->next) {
418                                         /* check for activity on the connection */
419                                         FD_SET(c->fd, &read_fds);
420                                         if (c->fd > fd_max)
421                                                 fd_max = c->fd;
422                                 }
423                         }
424                 }
425
426                 struct timeval tv;
427                 tv.tv_sec = 0;
428                 if (poll_ok) {
429                         /* we're just polling this iteration, this is faster on embedded
430                          * hosts */
431                         tv.tv_usec = 0;
432                         retval = socket_select(fd_max + 1, &read_fds, NULL, NULL, &tv);
433                 } else {
434                         /* Every 100ms, can be changed with "poll_period" command */
435                         tv.tv_usec = polling_period * 1000;
436                         /* Only while we're sleeping we'll let others run */
437                         openocd_sleep_prelude();
438                         kept_alive();
439                         retval = socket_select(fd_max + 1, &read_fds, NULL, NULL, &tv);
440                         openocd_sleep_postlude();
441                 }
442
443                 if (retval == -1) {
444 #ifdef _WIN32
445
446                         errno = WSAGetLastError();
447
448                         if (errno == WSAEINTR)
449                                 FD_ZERO(&read_fds);
450                         else {
451                                 LOG_ERROR("error during select: %s", strerror(errno));
452                                 return ERROR_FAIL;
453                         }
454 #else
455
456                         if (errno == EINTR)
457                                 FD_ZERO(&read_fds);
458                         else {
459                                 LOG_ERROR("error during select: %s", strerror(errno));
460                                 return ERROR_FAIL;
461                         }
462 #endif
463                 }
464
465                 if (retval == 0) {
466                         /* We only execute these callbacks when there was nothing to do or we timed
467                          *out */
468                         target_call_timer_callbacks();
469                         process_jim_events(command_context);
470
471                         FD_ZERO(&read_fds);     /* eCos leaves read_fds unchanged in this case!  */
472
473                         /* We timed out/there was nothing to do, timeout rather than poll next time
474                          **/
475                         poll_ok = false;
476                 } else {
477                         /* There was something to do, next time we'll just poll */
478                         poll_ok = true;
479                 }
480
481                 /* This is a simple back-off algorithm where we immediately
482                  * re-poll if we did something this time around.
483                  *
484                  * This greatly improves performance of DCC.
485                  */
486                 poll_ok = poll_ok || target_got_message();
487
488                 for (service = services; service; service = service->next) {
489                         /* handle new connections on listeners */
490                         if ((service->fd != -1)
491                             && (FD_ISSET(service->fd, &read_fds))) {
492                                 if (service->max_connections != 0)
493                                         add_connection(service, command_context);
494                                 else {
495                                         if (service->type == CONNECTION_TCP) {
496                                                 struct sockaddr_in sin;
497                                                 socklen_t address_size = sizeof(sin);
498                                                 int tmp_fd;
499                                                 tmp_fd = accept(service->fd,
500                                                                 (struct sockaddr *)&service->sin,
501                                                                 &address_size);
502                                                 close_socket(tmp_fd);
503                                         }
504                                         LOG_INFO(
505                                                 "rejected '%s' connection, no more connections allowed",
506                                                 service->name);
507                                 }
508                         }
509
510                         /* handle activity on connections */
511                         if (service->connections) {
512                                 struct connection *c;
513
514                                 for (c = service->connections; c; ) {
515                                         if ((FD_ISSET(c->fd, &read_fds)) || c->input_pending) {
516                                                 retval = service->input(c);
517                                                 if (retval != ERROR_OK) {
518                                                         struct connection *next = c->next;
519                                                         if (service->type == CONNECTION_PIPE ||
520                                                                         service->type == CONNECTION_STDINOUT) {
521                                                                 /* if connection uses a pipe then
522                                                                  * shutdown openocd on error */
523                                                                 shutdown_openocd = 1;
524                                                         }
525                                                         remove_connection(service, c);
526                                                         LOG_INFO("dropped '%s' connection",
527                                                                 service->name);
528                                                         c = next;
529                                                         continue;
530                                                 }
531                                         }
532                                         c = c->next;
533                                 }
534                         }
535                 }
536
537 #ifdef _WIN32
538                 MSG msg;
539                 while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
540                         if (msg.message == WM_QUIT)
541                                 shutdown_openocd = 1;
542                 }
543 #endif
544         }
545
546         return shutdown_openocd != 2 ? ERROR_OK : ERROR_FAIL;
547 }
548
549 #ifdef _WIN32
550 BOOL WINAPI ControlHandler(DWORD dwCtrlType)
551 {
552         shutdown_openocd = 1;
553         return TRUE;
554 }
555 #endif
556
557 void sig_handler(int sig)
558 {
559         /* store only first signal that hits us */
560         if (!last_signal)
561                 last_signal = sig;
562         shutdown_openocd = 1;
563 }
564
565 int server_preinit(void)
566 {
567         /* this currently only calls WSAStartup on native win32 systems
568          * before any socket operations are performed.
569          * This is an issue if you call init in your config script */
570
571 #ifdef _WIN32
572         WORD wVersionRequested;
573         WSADATA wsaData;
574
575         wVersionRequested = MAKEWORD(2, 2);
576
577         if (WSAStartup(wVersionRequested, &wsaData) != 0) {
578                 LOG_ERROR("Failed to Open Winsock");
579                 return ERROR_FAIL;
580         }
581
582         /* register ctrl-c handler */
583         SetConsoleCtrlHandler(ControlHandler, TRUE);
584
585         signal(SIGBREAK, sig_handler);
586 #endif
587         signal(SIGINT, sig_handler);
588         signal(SIGTERM, sig_handler);
589         signal(SIGABRT, sig_handler);
590
591         return ERROR_OK;
592 }
593
594 int server_init(struct command_context *cmd_ctx)
595 {
596         int ret = tcl_init();
597
598         if (ret != ERROR_OK)
599                 return ret;
600
601         ret = telnet_init("Open On-Chip Debugger");
602
603         if (ret != ERROR_OK) {
604                 remove_services();
605                 return ret;
606         }
607
608         return ERROR_OK;
609 }
610
611 int server_quit(void)
612 {
613         remove_services();
614         target_quit();
615
616 #ifdef _WIN32
617         WSACleanup();
618         SetConsoleCtrlHandler(ControlHandler, FALSE);
619
620         return ERROR_OK;
621 #endif
622
623         /* return signal number so we can kill ourselves */
624         return last_signal;
625 }
626
627 void exit_on_signal(int sig)
628 {
629 #ifndef _WIN32
630         /* bring back default system handler and kill yourself */
631         signal(sig, SIG_DFL);
632         kill(getpid(), sig);
633 #endif
634 }
635
636 int connection_write(struct connection *connection, const void *data, int len)
637 {
638         if (len == 0) {
639                 /* successful no-op. Sockets and pipes behave differently here... */
640                 return 0;
641         }
642         if (connection->service->type == CONNECTION_TCP)
643                 return write_socket(connection->fd_out, data, len);
644         else
645                 return write(connection->fd_out, data, len);
646 }
647
648 int connection_read(struct connection *connection, void *data, int len)
649 {
650         if (connection->service->type == CONNECTION_TCP)
651                 return read_socket(connection->fd, data, len);
652         else
653                 return read(connection->fd, data, len);
654 }
655
656 /* tell the server we want to shut down */
657 COMMAND_HANDLER(handle_shutdown_command)
658 {
659         LOG_USER("shutdown command invoked");
660
661         shutdown_openocd = 1;
662
663         if (CMD_ARGC == 1) {
664                 if (!strcmp(CMD_ARGV[0], "error")) {
665                         shutdown_openocd = 2;
666                         return ERROR_FAIL;
667                 }
668         }
669
670         return ERROR_COMMAND_CLOSE_CONNECTION;
671 }
672
673 COMMAND_HANDLER(handle_poll_period_command)
674 {
675         if (CMD_ARGC == 0)
676                 LOG_WARNING("You need to set a period value");
677         else
678                 COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], polling_period);
679
680         LOG_INFO("set servers polling period to %ums", polling_period);
681
682         return ERROR_OK;
683 }
684
685 COMMAND_HANDLER(handle_bindto_command)
686 {
687         switch (CMD_ARGC) {
688                 case 0:
689                         command_print(CMD_CTX, "bindto name: %s", bindto_name);
690                         break;
691                 case 1:
692                         free(bindto_name);
693                         bindto_name = strdup(CMD_ARGV[0]);
694                         break;
695                 default:
696                         return ERROR_COMMAND_SYNTAX_ERROR;
697         }
698         return ERROR_OK;
699 }
700
701 static const struct command_registration server_command_handlers[] = {
702         {
703                 .name = "shutdown",
704                 .handler = &handle_shutdown_command,
705                 .mode = COMMAND_ANY,
706                 .usage = "",
707                 .help = "shut the server down",
708         },
709         {
710                 .name = "poll_period",
711                 .handler = &handle_poll_period_command,
712                 .mode = COMMAND_ANY,
713                 .usage = "",
714                 .help = "set the servers polling period",
715         },
716         {
717                 .name = "bindto",
718                 .handler = &handle_bindto_command,
719                 .mode = COMMAND_ANY,
720                 .usage = "[name]",
721                 .help = "Specify address by name on which to listen for "
722                     "incoming TCP/IP connections",
723         },
724         COMMAND_REGISTRATION_DONE
725 };
726
727 int server_register_commands(struct command_context *cmd_ctx)
728 {
729         int retval = telnet_register_commands(cmd_ctx);
730         if (ERROR_OK != retval)
731                 return retval;
732
733         retval = tcl_register_commands(cmd_ctx);
734         if (ERROR_OK != retval)
735                 return retval;
736
737         retval = jsp_register_commands(cmd_ctx);
738         if (ERROR_OK != retval)
739                 return retval;
740
741         return register_commands(cmd_ctx, NULL, server_command_handlers);
742 }
743
744 COMMAND_HELPER(server_port_command, unsigned short *out)
745 {
746         switch (CMD_ARGC) {
747                 case 0:
748                         command_print(CMD_CTX, "%d", *out);
749                         break;
750                 case 1:
751                 {
752                         uint16_t port;
753                         COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], port);
754                         *out = port;
755                         break;
756                 }
757                 default:
758                         return ERROR_COMMAND_SYNTAX_ERROR;
759         }
760         return ERROR_OK;
761 }
762
763 COMMAND_HELPER(server_pipe_command, char **out)
764 {
765         switch (CMD_ARGC) {
766                 case 0:
767                         command_print(CMD_CTX, "%s", *out);
768                         break;
769                 case 1:
770                 {
771                         if (CMD_CTX->mode == COMMAND_EXEC) {
772                                 LOG_WARNING("unable to change server port after init");
773                                 return ERROR_COMMAND_ARGUMENT_INVALID;
774                         }
775                         free(*out);
776                         *out = strdup(CMD_ARGV[0]);
777                         break;
778                 }
779                 default:
780                         return ERROR_COMMAND_SYNTAX_ERROR;
781         }
782         return ERROR_OK;
783 }