remove obsolete debug msgs
[project/ubus.git] / libubus.c
1 #include <sys/types.h>
2 #include <sys/uio.h>
3 #include <sys/socket.h>
4 #include <unistd.h>
5
6 #include <libubox/blob.h>
7 #include <libubox/blobmsg.h>
8 #include <libubox/usock.h>
9
10 #include "libubus.h"
11 #include "ubusmsg.h"
12
13 #define DEBUG 1
14
15 #ifdef DEBUG
16 #define DPRINTF(_format, ...) fprintf(stderr, "ubus: " _format, ## __VA_ARGS__)
17 #else
18 #define DPRINTF(...) do {} while(0)
19 #endif
20
21 #define STATIC_IOV(_var) { .iov_base = (char *) &(_var), .iov_len = sizeof(_var) }
22
23 const char *__ubus_strerror[__UBUS_STATUS_LAST] = {
24 [UBUS_STATUS_OK] = "Success",
25 [UBUS_STATUS_INVALID_COMMAND] = "Invalid command",
26 [UBUS_STATUS_INVALID_ARGUMENT] = "Invalid argument",
27 [UBUS_STATUS_METHOD_NOT_FOUND] = "Method not found",
28 [UBUS_STATUS_NOT_FOUND] = "Not found",
29 [UBUS_STATUS_NO_DATA] = "No response",
30 };
31
32 static struct blob_buf b;
33
34 static const struct blob_attr_info ubus_policy[UBUS_ATTR_MAX] = {
35 [UBUS_ATTR_STATUS] = { .type = BLOB_ATTR_INT32 },
36 [UBUS_ATTR_OBJID] = { .type = BLOB_ATTR_INT32 },
37 [UBUS_ATTR_OBJPATH] = { .type = BLOB_ATTR_STRING },
38 [UBUS_ATTR_METHOD] = { .type = BLOB_ATTR_STRING },
39 };
40 static struct blob_attr *attrbuf[UBUS_ATTR_MAX];
41
42 struct ubus_pending_data {
43 struct list_head list;
44 int type;
45 struct blob_attr data[];
46 };
47
48 static int ubus_cmp_id(const void *k1, const void *k2, void *ptr)
49 {
50 const uint32_t *id1 = k1, *id2 = k2;
51
52 if (*id1 < *id2)
53 return -1;
54 else
55 return *id1 > *id2;
56 }
57
58 static struct blob_attr **ubus_parse_msg(struct blob_attr *msg)
59 {
60 blob_parse(msg, attrbuf, ubus_policy, UBUS_ATTR_MAX);
61 return attrbuf;
62 }
63
64 const char *ubus_strerror(int error)
65 {
66 static char err[32];
67
68 if (error < 0 || error >= __UBUS_STATUS_LAST)
69 goto out;
70
71 if (!__ubus_strerror[error])
72 goto out;
73
74 return __ubus_strerror[error];
75
76 out:
77 sprintf(err, "Unknown error: %d", error);
78 return err;
79 }
80
81 static int ubus_send_msg(struct ubus_context *ctx, uint32_t seq,
82 struct blob_attr *msg, int cmd, uint32_t peer)
83 {
84 struct ubus_msghdr hdr;
85 struct iovec iov[2] = {
86 STATIC_IOV(hdr)
87 };
88
89 hdr.version = 0;
90 hdr.type = cmd;
91 hdr.seq = seq;
92 hdr.peer = peer;
93
94 if (!msg) {
95 blob_buf_init(&b, 0);
96 msg = b.head;
97 }
98
99 iov[1].iov_base = (char *) msg;
100 iov[1].iov_len = blob_raw_len(msg);
101
102 return writev(ctx->sock.fd, iov, 2);
103 }
104
105 static int ubus_start_request(struct ubus_context *ctx, struct ubus_request *req,
106 struct blob_attr *msg, int cmd, uint32_t peer)
107 {
108 memset(req, 0, sizeof(*req));
109
110 INIT_LIST_HEAD(&req->list);
111 INIT_LIST_HEAD(&req->pending);
112 req->ctx = ctx;
113 req->peer = peer;
114 req->seq = ++ctx->request_seq;
115 return ubus_send_msg(ctx, req->seq, msg, cmd, peer);
116 }
117
118 static bool recv_retry(int fd, struct iovec *iov, bool wait)
119 {
120 int bytes;
121
122 while (iov->iov_len > 0) {
123 bytes = read(fd, iov->iov_base, iov->iov_len);
124 if (bytes < 0) {
125 bytes = 0;
126 if (errno == EINTR)
127 continue;
128
129 if (errno != EAGAIN) {
130 perror("read");
131 return false;
132 }
133 }
134 if (!wait && !bytes)
135 return false;
136
137 wait = true;
138 iov->iov_len -= bytes;
139 iov->iov_base += bytes;
140 }
141
142 return true;
143 }
144
145 static bool ubus_validate_hdr(struct ubus_msghdr *hdr)
146 {
147 if (hdr->version != 0)
148 return false;
149
150 if (blob_raw_len(hdr->data) < sizeof(*hdr->data))
151 return false;
152
153 if (blob_raw_len(hdr->data) + sizeof(*hdr) > UBUS_MAX_MSGLEN)
154 return false;
155
156 return true;
157 }
158
159 static bool get_next_msg(struct ubus_context *ctx, bool wait)
160 {
161 struct iovec iov = STATIC_IOV(ctx->msgbuf.hdr);
162
163 /* receive header + start attribute */
164 iov.iov_len += sizeof(struct blob_attr);
165 if (!recv_retry(ctx->sock.fd, &iov, wait))
166 return false;
167
168 iov.iov_len = blob_len(ctx->msgbuf.hdr.data);
169 if (iov.iov_len > 0 && !recv_retry(ctx->sock.fd, &iov, true))
170 return false;
171
172 return ubus_validate_hdr(&ctx->msgbuf.hdr);
173 }
174
175 static bool ubus_get_status(struct ubus_msghdr *hdr, int *ret)
176 {
177 ubus_parse_msg(hdr->data);
178
179 if (!attrbuf[UBUS_ATTR_STATUS])
180 return false;
181
182 *ret = blob_get_int32(attrbuf[UBUS_ATTR_STATUS]);
183 return true;
184 }
185
186 static void req_data_cb(struct ubus_request *req, int type, struct blob_attr *data)
187 {
188 struct blob_attr **attr;
189
190 if (req->raw_data_cb)
191 req->raw_data_cb(req, type, data);
192
193 if (!req->data_cb)
194 return;
195
196 attr = ubus_parse_msg(data);
197 req->data_cb(req, type, attr[UBUS_ATTR_DATA]);
198 }
199
200 static void ubus_process_req_data(struct ubus_request *req)
201 {
202 struct ubus_pending_data *data;
203
204 while (!list_empty(&req->pending)) {
205 data = list_first_entry(&req->pending,
206 struct ubus_pending_data, list);
207 list_del(&data->list);
208 if (!req->cancelled)
209 req_data_cb(req, data->type, data->data);
210 free(data);
211 }
212 }
213
214 static void ubus_req_complete_cb(struct ubus_request *req)
215 {
216 ubus_complete_handler_t cb = req->complete_cb;
217
218 if (!cb)
219 return;
220
221 req->complete_cb = NULL;
222 cb(req, req->status_code);
223 }
224
225 static int ubus_process_req_status(struct ubus_request *req, struct ubus_msghdr *hdr)
226 {
227 int ret = UBUS_STATUS_INVALID_ARGUMENT;
228
229 if (!list_empty(&req->list))
230 list_del(&req->list);
231
232 ubus_get_status(hdr, &ret);
233 req->peer = hdr->peer;
234 req->status_msg = true;
235 req->status_code = ret;
236 if (!req->blocked)
237 ubus_req_complete_cb(req);
238
239 return ret;
240 }
241
242 static void ubus_req_data(struct ubus_request *req, struct ubus_msghdr *hdr)
243 {
244 struct ubus_pending_data *data;
245 int len;
246
247 if (!req->blocked) {
248 req->blocked = true;
249 req_data_cb(req, hdr->type, hdr->data);
250 ubus_process_req_data(req);
251 req->blocked = false;
252
253 if (req->status_msg)
254 ubus_req_complete_cb(req);
255
256 return;
257 }
258
259 len = blob_raw_len(hdr->data);
260 data = calloc(1, sizeof(*data) + len);
261 if (!data)
262 return;
263
264 data->type = hdr->type;
265 memcpy(data->data, hdr->data, len);
266 list_add(&data->list, &req->pending);
267 }
268
269 static struct ubus_request *ubus_find_request(struct ubus_context *ctx, uint32_t seq, uint32_t peer)
270 {
271 struct ubus_request *req;
272
273 list_for_each_entry(req, &ctx->requests, list) {
274 if (seq != req->seq || peer != req->peer)
275 continue;
276
277 return req;
278 }
279 return NULL;
280 }
281
282 static void ubus_process_invoke(struct ubus_context *ctx, struct ubus_msghdr *hdr)
283 {
284 struct ubus_request_data req;
285 struct ubus_object *obj;
286 uint32_t objid = 0;
287 int method;
288 int ret = 0;
289
290 ubus_parse_msg(hdr->data);
291
292 if (!attrbuf[UBUS_ATTR_OBJID])
293 return;
294
295 objid = blob_get_int32(attrbuf[UBUS_ATTR_OBJID]);
296
297 if (!attrbuf[UBUS_ATTR_METHOD]) {
298 ret = UBUS_STATUS_INVALID_ARGUMENT;
299 goto send;
300 }
301
302 obj = avl_find_element(&ctx->objects, &objid, obj, avl);
303 if (!obj) {
304 ret = UBUS_STATUS_NOT_FOUND;
305 goto send;
306 }
307
308 for (method = 0; method < obj->n_methods; method++)
309 if (!strcmp(obj->methods[method].name,
310 blob_data(attrbuf[UBUS_ATTR_METHOD])))
311 goto found;
312
313 /* not found */
314 ret = UBUS_STATUS_METHOD_NOT_FOUND;
315 goto send;
316
317 found:
318 req.object = objid;
319 req.peer = hdr->peer;
320 req.seq = hdr->seq;
321 ret = obj->methods[method].handler(ctx, obj, &req,
322 obj->methods[method].name,
323 attrbuf[UBUS_ATTR_DATA]);
324
325 send:
326 blob_buf_init(&b, 0);
327 blob_put_int32(&b, UBUS_ATTR_STATUS, ret);
328 blob_put_int32(&b, UBUS_ATTR_OBJID, objid);
329 ubus_send_msg(ctx, hdr->seq, b.head, UBUS_MSG_STATUS, hdr->peer);
330 }
331
332 static void ubus_process_msg(struct ubus_context *ctx, struct ubus_msghdr *hdr)
333 {
334 struct ubus_request *req;
335
336 switch(hdr->type) {
337 case UBUS_MSG_STATUS:
338 req = ubus_find_request(ctx, hdr->seq, hdr->peer);
339 if (!req)
340 break;
341
342 ubus_process_req_status(req, hdr);
343 break;
344
345 case UBUS_MSG_DATA:
346 req = ubus_find_request(ctx, hdr->seq, hdr->peer);
347 if (req && (req->data_cb || req->raw_data_cb))
348 ubus_req_data(req, hdr);
349 break;
350
351 case UBUS_MSG_INVOKE:
352 ubus_process_invoke(ctx, hdr);
353 break;
354 default:
355 DPRINTF("unknown message type: %d\n", hdr->type);
356 break;
357 }
358 }
359
360 void ubus_abort_request(struct ubus_context *ctx, struct ubus_request *req)
361 {
362 if (!list_empty(&req->list))
363 return;
364
365 req->cancelled = true;
366 ubus_process_req_data(req);
367 list_del(&req->list);
368 }
369
370 void ubus_complete_request_async(struct ubus_context *ctx, struct ubus_request *req)
371 {
372 if (!list_empty(&req->list))
373 return;
374
375 list_add(&req->list, &ctx->requests);
376 }
377
378 static void ubus_handle_data(struct uloop_fd *u, unsigned int events)
379 {
380 struct ubus_context *ctx = container_of(u, struct ubus_context, sock);
381 struct ubus_msghdr *hdr = &ctx->msgbuf.hdr;
382
383 while (get_next_msg(ctx, false))
384 ubus_process_msg(ctx, hdr);
385
386 if (u->eof)
387 ctx->connection_lost(ctx);
388 }
389
390 int ubus_complete_request(struct ubus_context *ctx, struct ubus_request *req)
391 {
392 struct ubus_msghdr *hdr = &ctx->msgbuf.hdr;
393
394 if (!list_empty(&req->list))
395 list_del(&req->list);
396
397 while (1) {
398 if (req->status_msg)
399 return req->status_code;
400
401 if (req->cancelled)
402 return UBUS_STATUS_NO_DATA;
403
404 if (!get_next_msg(ctx, true))
405 return UBUS_STATUS_NO_DATA;
406
407 if (hdr->seq != req->seq || hdr->peer != req->peer)
408 goto skip;
409
410 switch(hdr->type) {
411 case UBUS_MSG_STATUS:
412 return ubus_process_req_status(req, hdr);
413 case UBUS_MSG_DATA:
414 if (req->data_cb || req->raw_data_cb)
415 ubus_req_data(req, hdr);
416 continue;
417 default:
418 goto skip;
419 }
420
421 skip:
422 ubus_process_msg(ctx, hdr);
423 }
424 }
425
426 struct ubus_lookup_request {
427 struct ubus_request req;
428 ubus_lookup_handler_t cb;
429 };
430
431 static void ubus_lookup_cb(struct ubus_request *ureq, int type, struct blob_attr *msg)
432 {
433 struct ubus_lookup_request *req;
434 struct ubus_object_data obj;
435 struct blob_attr **attr;
436
437 req = container_of(ureq, struct ubus_lookup_request, req);
438 attr = ubus_parse_msg(msg);
439
440 if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_OBJPATH] ||
441 !attr[UBUS_ATTR_OBJTYPE])
442 return;
443
444 memset(&obj, 0, sizeof(obj));
445 obj.id = blob_get_int32(attr[UBUS_ATTR_OBJID]);
446 obj.path = blob_data(attr[UBUS_ATTR_OBJPATH]);
447 obj.type_id = blob_get_int32(attr[UBUS_ATTR_OBJTYPE]);
448 obj.signature = attr[UBUS_ATTR_SIGNATURE];
449 req->cb(ureq->ctx, &obj, ureq->priv);
450 }
451
452 int ubus_lookup(struct ubus_context *ctx, const char *path,
453 ubus_lookup_handler_t cb, void *priv)
454 {
455 struct ubus_lookup_request lookup;
456
457 blob_buf_init(&b, 0);
458 if (path)
459 blob_put_string(&b, UBUS_ATTR_OBJPATH, path);
460 ubus_start_request(ctx, &lookup.req, b.head, UBUS_MSG_LOOKUP, 0);
461 lookup.req.raw_data_cb = ubus_lookup_cb;
462 lookup.req.priv = priv;
463 lookup.cb = cb;
464 return ubus_complete_request(ctx, &lookup.req);
465 }
466
467 static void ubus_lookup_id_cb(struct ubus_request *req, int type, struct blob_attr *msg)
468 {
469 struct blob_attr **attr;
470 uint32_t *id = req->priv;
471
472 attr = ubus_parse_msg(msg);
473
474 if (!attr[UBUS_ATTR_OBJID])
475 return;
476
477 *id = blob_get_int32(attr[UBUS_ATTR_OBJID]);
478 }
479
480 int ubus_lookup_id(struct ubus_context *ctx, const char *path, uint32_t *id)
481 {
482 struct ubus_request req;
483
484 blob_buf_init(&b, 0);
485 if (path)
486 blob_put_string(&b, UBUS_ATTR_OBJPATH, path);
487 ubus_start_request(ctx, &req, b.head, UBUS_MSG_LOOKUP, 0);
488 req.raw_data_cb = ubus_lookup_id_cb;
489 req.priv = id;
490
491 return ubus_complete_request(ctx, &req);
492 }
493
494 int ubus_send_reply(struct ubus_context *ctx, struct ubus_request_data *req,
495 struct blob_attr *msg)
496 {
497 int ret;
498
499 blob_buf_init(&b, 0);
500 blob_put_int32(&b, UBUS_ATTR_OBJID, req->object);
501 blob_put(&b, UBUS_ATTR_DATA, blob_data(msg), blob_len(msg));
502 ret = ubus_send_msg(ctx, req->seq, b.head, UBUS_MSG_DATA, req->peer);
503 if (ret < 0)
504 return UBUS_STATUS_NO_DATA;
505
506 return 0;
507 }
508
509 void ubus_invoke_async(struct ubus_context *ctx, uint32_t obj, const char *method,
510 struct blob_attr *msg, struct ubus_request *req)
511 {
512 blob_buf_init(&b, 0);
513 blob_put_int32(&b, UBUS_ATTR_OBJID, obj);
514 blob_put_string(&b, UBUS_ATTR_METHOD, method);
515 if (msg)
516 blob_put(&b, UBUS_ATTR_DATA, blob_data(msg), blob_len(msg));
517
518 ubus_start_request(ctx, req, b.head, UBUS_MSG_INVOKE, obj);
519 }
520
521 int ubus_invoke(struct ubus_context *ctx, uint32_t obj, const char *method,
522 struct blob_attr *msg, ubus_data_handler_t cb, void *priv)
523 {
524 struct ubus_request req;
525
526 ubus_invoke_async(ctx, obj, method, msg, &req);
527 req.data_cb = cb;
528 req.priv = priv;
529 return ubus_complete_request(ctx, &req);
530 }
531
532 static void ubus_publish_cb(struct ubus_request *req, int type, struct blob_attr *msg)
533 {
534 struct ubus_object *obj = req->priv;
535
536 ubus_parse_msg(msg);
537
538 if (!attrbuf[UBUS_ATTR_OBJID])
539 return;
540
541 obj->id = blob_get_int32(attrbuf[UBUS_ATTR_OBJID]);
542
543 if (attrbuf[UBUS_ATTR_OBJTYPE])
544 obj->type->id = blob_get_int32(attrbuf[UBUS_ATTR_OBJTYPE]);
545
546 obj->avl.key = &obj->id;
547 avl_insert(&req->ctx->objects, &obj->avl);
548 }
549
550 static bool ubus_push_table_data(const struct ubus_signature **sig, int *rem, bool array)
551 {
552 const struct ubus_signature *cur;
553 bool nest_type;
554 void *nest;
555
556 while (rem) {
557 cur = (*sig)++;
558 (*rem)--;
559 switch(cur->type) {
560 case UBUS_SIGNATURE_END:
561 return !array;
562 case BLOBMSG_TYPE_INT32:
563 case BLOBMSG_TYPE_STRING:
564 blobmsg_add_u32(&b, cur->name, cur->type);
565 break;
566 case BLOBMSG_TYPE_TABLE:
567 case BLOBMSG_TYPE_ARRAY:
568 nest_type = cur->type == BLOBMSG_TYPE_ARRAY;
569 nest = blobmsg_open_nested(&b, cur->name, nest_type);
570 if (!ubus_push_table_data(sig, rem, nest_type))
571 return false;
572 blobmsg_close_table(&b, nest);
573 break;
574 default:
575 return false;
576 }
577 if (array)
578 return true;
579 }
580 return false;
581 }
582
583 static bool ubus_push_object_type(struct ubus_object_type *type)
584 {
585 void *s, *m;
586 int rem = type->n_signature;
587 const struct ubus_signature *sig = type->signature;
588
589 s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
590 while (rem) {
591 if (sig->type != UBUS_SIGNATURE_METHOD)
592 return false;
593
594 m = blobmsg_open_table(&b, sig->name);
595
596 sig++;
597 rem--;
598 if (!ubus_push_table_data(&sig, &rem, false))
599 return false;
600
601 blobmsg_close_table(&b, m);
602 }
603 blob_nest_end(&b, s);
604
605 return true;
606 }
607
608 int ubus_publish(struct ubus_context *ctx, struct ubus_object *obj)
609 {
610 struct ubus_request req;
611 int ret;
612
613 if (obj->id || !obj->name || !obj->type)
614 return UBUS_STATUS_INVALID_ARGUMENT;
615
616 blob_buf_init(&b, 0);
617 blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->name);
618
619 if (obj->type->id)
620 blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id);
621 else if (!ubus_push_object_type(obj->type))
622 return UBUS_STATUS_INVALID_ARGUMENT;
623
624 ubus_start_request(ctx, &req, b.head, UBUS_MSG_PUBLISH, 0);
625 req.raw_data_cb = ubus_publish_cb;
626 req.priv = obj;
627 ret = ubus_complete_request(ctx, &req);
628 if (ret)
629 return ret;
630
631 if (!obj->id)
632 return UBUS_STATUS_NO_DATA;
633
634 return 0;
635 }
636
637 void ubus_default_connection_lost(struct ubus_context *ctx)
638 {
639 if (ctx->sock.registered)
640 uloop_end();
641 }
642
643 struct ubus_context *ubus_connect(const char *path)
644 {
645 struct ubus_context *ctx;
646 struct {
647 struct ubus_msghdr hdr;
648 struct blob_attr data;
649 } hdr;
650 struct blob_attr *buf;
651
652 if (!path)
653 path = UBUS_UNIX_SOCKET;
654
655 ctx = calloc(1, sizeof(*ctx));
656 if (!ctx)
657 goto error;
658
659 ctx->sock.fd = usock(USOCK_UNIX, path, NULL);
660 if (ctx->sock.fd < 0)
661 goto error_free;
662
663 ctx->sock.cb = ubus_handle_data;
664
665 if (read(ctx->sock.fd, &hdr, sizeof(hdr)) != sizeof(hdr))
666 goto error_close;
667
668 if (!ubus_validate_hdr(&hdr.hdr))
669 goto error_close;
670
671 if (hdr.hdr.type != UBUS_MSG_HELLO)
672 goto error_close;
673
674 buf = calloc(1, blob_raw_len(&hdr.data));
675 if (!buf)
676 goto error_close;
677
678 memcpy(buf, &hdr.data, sizeof(hdr.data));
679 if (read(ctx->sock.fd, blob_data(buf), blob_len(buf)) != blob_len(buf))
680 goto error_free_buf;
681
682 ctx->local_id = hdr.hdr.peer;
683 free(buf);
684
685 ctx->connection_lost = ubus_default_connection_lost;
686
687 INIT_LIST_HEAD(&ctx->requests);
688 avl_init(&ctx->objects, ubus_cmp_id, false, NULL);
689
690 if (!ctx->local_id)
691 goto error_close;
692
693 return ctx;
694
695 error_free_buf:
696 free(buf);
697 error_close:
698 close(ctx->sock.fd);
699 error_free:
700 free(ctx);
701 error:
702 return NULL;
703 }
704
705 void ubus_free(struct ubus_context *ctx)
706 {
707 close(ctx->sock.fd);
708 free(ctx);
709 }