src/afb-hook.c

   1 /*
   2  * Copyright (C) 2016, 2017 "IoT.bzh"
   3  * Author José Bollo <jose.bollo@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #define _GNU_SOURCE
  19
  20 #include <limits.h>
  21 #include <stdio.h>
  22 #include <stdarg.h>
  23 #include <string.h>
  24 #include <pthread.h>
  25 #include <unistd.h>
  26 #include <fnmatch.h>
  27 #include <sys/uio.h>
  28
  29 #include <json-c/json.h>
  30
  31 #include <afb/afb-req-common.h>
  32 #include <afb/afb-event-itf.h>
  33
  34 #include "afb-context.h"
  35 #include "afb-hook.h"
  36 #include "afb-session.h"
  37 #include "afb-cred.h"
  38 #include "afb-xreq.h"
  39 #include "afb-ditf.h"
  40 #include "afb-svc.h"
  41 #include "afb-evt.h"
  42 #include "verbose.h"
  43
  44 /**
  45  * Definition of a hook for xreq
  46  */
  47 struct afb_hook_xreq {
  48         struct afb_hook_xreq *next; /**< next hook */
  49         unsigned refcount; /**< reference count */
  50         char *api; /**< api hooked or NULL for any */
  51         char *verb; /**< verb hooked or NULL for any */
  52         struct afb_session *session; /**< session hooked or NULL if any */
  53         unsigned flags; /**< hook flags */
  54         struct afb_hook_xreq_itf *itf; /**< interface of hook */
  55         void *closure; /**< closure for callbacks */
  56 };
  57
  58 /**
  59  * Definition of a hook for ditf
  60  */
  61 struct afb_hook_ditf {
  62         struct afb_hook_ditf *next; /**< next hook */
  63         unsigned refcount; /**< reference count */
  64         char *api; /**< api hooked or NULL for any */
  65         unsigned flags; /**< hook flags */
  66         struct afb_hook_ditf_itf *itf; /**< interface of hook */
  67         void *closure; /**< closure for callbacks */
  68 };
  69
  70 /**
  71  * Definition of a hook for svc
  72  */
  73 struct afb_hook_svc {
  74         struct afb_hook_svc *next; /**< next hook */
  75         unsigned refcount; /**< reference count */
  76         char *api; /**< api hooked or NULL for any */
  77         unsigned flags; /**< hook flags */
  78         struct afb_hook_svc_itf *itf; /**< interface of hook */
  79         void *closure; /**< closure for callbacks */
  80 };
  81
  82 /**
  83  * Definition of a hook for evt
  84  */
  85 struct afb_hook_evt {
  86         struct afb_hook_evt *next; /**< next hook */
  87         unsigned refcount; /**< reference count */
  88         char *pattern; /**< event pattern name hooked or NULL for any */
  89         unsigned flags; /**< hook flags */
  90         struct afb_hook_evt_itf *itf; /**< interface of hook */
  91         void *closure; /**< closure for callbacks */
  92 };
  93
  94 /**
  95  * Definition of a hook for global
  96  */
  97 struct afb_hook_global {
  98         struct afb_hook_global *next; /**< next hook */
  99         unsigned refcount; /**< reference count */
 100         unsigned flags; /**< hook flags */
 101         struct afb_hook_global_itf *itf; /**< interface of hook */
 102         void *closure; /**< closure for callbacks */
 103 };
 104
 105 /* synchronisation across threads */
 106 static pthread_rwlock_t rwlock = PTHREAD_RWLOCK_INITIALIZER;
 107
 108 /* list of hooks for xreq */
 109 static struct afb_hook_xreq *list_of_xreq_hooks = NULL;
 110
 111 /* list of hooks for ditf */
 112 static struct afb_hook_ditf *list_of_ditf_hooks = NULL;
 113
 114 /* list of hooks for svc */
 115 static struct afb_hook_svc *list_of_svc_hooks = NULL;
 116
 117 /* list of hooks for evt */
 118 static struct afb_hook_evt *list_of_evt_hooks = NULL;
 119
 120 /* list of hooks for global */
 121 static struct afb_hook_global *list_of_global_hooks = NULL;
 122
 123 /* hook id */
 124 static unsigned next_hookid = 0;
 125
 126 /******************************************************************************
 127  * section: hook id
 128  *****************************************************************************/
 129 static void init_hookid(struct afb_hookid *hookid)
 130 {
 131         hookid->id = __atomic_add_fetch(&next_hookid, 1, __ATOMIC_RELAXED);
 132         clock_gettime(CLOCK_MONOTONIC, &hookid->time);
 133 }
 134
 135 /******************************************************************************
 136  * section: default callbacks for tracing requests
 137  *****************************************************************************/
 138
 139 static char *_pbuf_(const char *fmt, va_list args, char **palloc, char *sbuf, size_t szsbuf, size_t *outlen)
 140 {
 141         int rc;
 142         va_list cp;
 143
 144         *palloc = NULL;
 145         va_copy(cp, args);
 146         rc = vsnprintf(sbuf, szsbuf, fmt, args);
 147         if ((size_t)rc >= szsbuf) {
 148                 sbuf[szsbuf-1] = 0;
 149                 sbuf[szsbuf-2] = sbuf[szsbuf-3] = sbuf[szsbuf-4] = '.';
 150                 rc = vasprintf(palloc, fmt, cp);
 151                 if (rc >= 0)
 152                         sbuf = *palloc;
 153         }
 154         va_end(cp);
 155         if (rc >= 0 && outlen)
 156                 *outlen = (size_t)rc;
 157         return sbuf;
 158 }
 159
 160 #if 0 /* old behaviour: use NOTICE */
 161 static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...)
 162 {
 163         char *tag, *data, *mem1, *mem2, buf1[256], buf2[2000];
 164         va_list arg1;
 165
 166         data = _pbuf_(fmt2, arg2, &mem2, buf2, sizeof buf2, NULL);
 167
 168         va_start(arg1, arg2);
 169         tag = _pbuf_(fmt1, arg1, &mem1, buf1, sizeof buf1, NULL);
 170         va_end(arg1);
 171
 172         NOTICE("[HOOK %s] %s", tag, data);
 173
 174         free(mem1);
 175         free(mem2);
 176 }
 177 #else /* new behaviour: emits directly to stderr */
 178 static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...)
 179 {
 180         static const char chars[] = "HOOK: [] \n";
 181         char *mem1, *mem2, buf1[256], buf2[2000];
 182         struct iovec iov[5];
 183         va_list arg1;
 184
 185         iov[0].iov_base = (void*)&chars[0];
 186         iov[0].iov_len = 7;
 187
 188         va_start(arg1, arg2);
 189         iov[1].iov_base = _pbuf_(fmt1, arg1, &mem1, buf1, sizeof buf1, &iov[1].iov_len);
 190         va_end(arg1);
 191
 192         iov[2].iov_base = (void*)&chars[7];
 193         iov[2].iov_len = 2;
 194
 195         iov[3].iov_base = _pbuf_(fmt2, arg2, &mem2, buf2, sizeof buf2, &iov[3].iov_len);
 196
 197         iov[4].iov_base = (void*)&chars[9];
 198         iov[4].iov_len = 1;
 199
 200         writev(2, iov, 5);
 201
 202         free(mem1);
 203         free(mem2);
 204 }
 205 #endif
 206
 207 static void _hook_xreq_(const struct afb_xreq *xreq, const char *format, ...)
 208 {
 209         va_list ap;
 210         va_start(ap, format);
 211         _hook_("xreq-%06d:%s/%s", format, ap, xreq->hookindex, xreq->api, xreq->verb);
 212         va_end(ap);
 213 }
 214
 215 static void hook_xreq_begin_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 216 {
 217         if (!xreq->cred)
 218                 _hook_xreq_(xreq, "BEGIN");
 219         else
 220                 _hook_xreq_(xreq, "BEGIN uid=%d=%s gid=%d pid=%d label=%s id=%s",
 221                         (int)xreq->cred->uid,
 222                         xreq->cred->user,
 223                         (int)xreq->cred->gid,
 224                         (int)xreq->cred->pid,
 225                         xreq->cred->label?:"(null)",
 226                         xreq->cred->id?:"(null)"
 227                 );
 228 }
 229
 230 static void hook_xreq_end_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 231 {
 232         _hook_xreq_(xreq, "END");
 233 }
 234
 235 static void hook_xreq_json_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *obj)
 236 {
 237         _hook_xreq_(xreq, "json() -> %s", json_object_to_json_string(obj));
 238 }
 239
 240 static void hook_xreq_get_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *name, struct afb_arg arg)
 241 {
 242         _hook_xreq_(xreq, "get(%s) -> { name: %s, value: %s, path: %s }", name, arg.name, arg.value, arg.path);
 243 }
 244
 245 static void hook_xreq_success_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *obj, const char *info)
 246 {
 247         _hook_xreq_(xreq, "success(%s, %s)", json_object_to_json_string(obj), info);
 248 }
 249
 250 static void hook_xreq_fail_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *status, const char *info)
 251 {
 252         _hook_xreq_(xreq, "fail(%s, %s)", status, info);
 253 }
 254
 255 static void hook_xreq_context_get_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, void *value)
 256 {
 257         _hook_xreq_(xreq, "context_get() -> %p", value);
 258 }
 259
 260 static void hook_xreq_context_set_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, void *value, void (*free_value)(void*))
 261 {
 262         _hook_xreq_(xreq, "context_set(%p, %p)", value, free_value);
 263 }
 264
 265 static void hook_xreq_addref_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 266 {
 267         _hook_xreq_(xreq, "addref()");
 268 }
 269
 270 static void hook_xreq_unref_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 271 {
 272         _hook_xreq_(xreq, "unref()");
 273 }
 274
 275 static void hook_xreq_session_close_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 276 {
 277         _hook_xreq_(xreq, "session_close()");
 278 }
 279
 280 static void hook_xreq_session_set_LOA_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, unsigned level, int result)
 281 {
 282         _hook_xreq_(xreq, "session_set_LOA(%u) -> %d", level, result);
 283 }
 284
 285 static void hook_xreq_subscribe_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_event event, int result)
 286 {
 287         _hook_xreq_(xreq, "subscribe(%s:%d) -> %d", afb_evt_event_name(event), afb_evt_event_id(event), result);
 288 }
 289
 290 static void hook_xreq_unsubscribe_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_event event, int result)
 291 {
 292         _hook_xreq_(xreq, "unsubscribe(%s:%d) -> %d", afb_evt_event_name(event), afb_evt_event_id(event), result);
 293 }
 294
 295 static void hook_xreq_subcall_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 296 {
 297         _hook_xreq_(xreq, "subcall(%s/%s, %s) ...", api, verb, json_object_to_json_string(args));
 298 }
 299
 300 static void hook_xreq_subcall_result_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int status, struct json_object *result)
 301 {
 302         _hook_xreq_(xreq, "    ...subcall... -> %d: %s", status, json_object_to_json_string(result));
 303 }
 304
 305 static void hook_xreq_subcallsync_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 306 {
 307         _hook_xreq_(xreq, "subcallsync(%s/%s, %s) ...", api, verb, json_object_to_json_string(args));
 308 }
 309
 310 static void hook_xreq_subcallsync_result_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int status, struct json_object *result)
 311 {
 312         _hook_xreq_(xreq, "    ...subcallsync... -> %d: %s", status, json_object_to_json_string(result));
 313 }
 314
 315 static void hook_xreq_vverbose_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int level, const char *file, int line, const char *func, const char *fmt, va_list args)
 316 {
 317         int len;
 318         char *msg;
 319         va_list ap;
 320
 321         va_copy(ap, args);
 322         len = vasprintf(&msg, fmt, ap);
 323         va_end(ap);
 324
 325         if (len < 0)
 326                 _hook_xreq_(xreq, "vverbose(%d, %s, %d, %s) -> %s ? ? ?", level, file, line, func, fmt);
 327         else {
 328                 _hook_xreq_(xreq, "vverbose(%d, %s, %d, %s) -> %s", level, file, line, func, msg);
 329                 free(msg);
 330         }
 331 }
 332
 333 static void hook_xreq_store_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_stored_req *sreq)
 334 {
 335         _hook_xreq_(xreq, "store() -> %p", sreq);
 336 }
 337
 338 static void hook_xreq_unstore_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 339 {
 340         _hook_xreq_(xreq, "unstore()");
 341 }
 342
 343 static void hook_xreq_subcall_req_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 344 {
 345         _hook_xreq_(xreq, "subcall_req(%s/%s, %s) ...", api, verb, json_object_to_json_string(args));
 346 }
 347
 348 static void hook_xreq_subcall_req_result_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int status, struct json_object *result)
 349 {
 350         _hook_xreq_(xreq, "    ...subcall_req... -> %d: %s", status, json_object_to_json_string(result));
 351 }
 352
 353 static void hook_xreq_has_permission_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *permission, int result)
 354 {
 355         _hook_xreq_(xreq, "has_permission(%s) -> %d", permission, result);
 356 }
 357
 358 static struct afb_hook_xreq_itf hook_xreq_default_itf = {
 359         .hook_xreq_begin = hook_xreq_begin_default_cb,
 360         .hook_xreq_end = hook_xreq_end_default_cb,
 361         .hook_xreq_json = hook_xreq_json_default_cb,
 362         .hook_xreq_get = hook_xreq_get_default_cb,
 363         .hook_xreq_success = hook_xreq_success_default_cb,
 364         .hook_xreq_fail = hook_xreq_fail_default_cb,
 365         .hook_xreq_context_get = hook_xreq_context_get_default_cb,
 366         .hook_xreq_context_set = hook_xreq_context_set_default_cb,
 367         .hook_xreq_addref = hook_xreq_addref_default_cb,
 368         .hook_xreq_unref = hook_xreq_unref_default_cb,
 369         .hook_xreq_session_close = hook_xreq_session_close_default_cb,
 370         .hook_xreq_session_set_LOA = hook_xreq_session_set_LOA_default_cb,
 371         .hook_xreq_subscribe = hook_xreq_subscribe_default_cb,
 372         .hook_xreq_unsubscribe = hook_xreq_unsubscribe_default_cb,
 373         .hook_xreq_subcall = hook_xreq_subcall_default_cb,
 374         .hook_xreq_subcall_result = hook_xreq_subcall_result_default_cb,
 375         .hook_xreq_subcallsync = hook_xreq_subcallsync_default_cb,
 376         .hook_xreq_subcallsync_result = hook_xreq_subcallsync_result_default_cb,
 377         .hook_xreq_vverbose = hook_xreq_vverbose_default_cb,
 378         .hook_xreq_store = hook_xreq_store_default_cb,
 379         .hook_xreq_unstore = hook_xreq_unstore_default_cb,
 380         .hook_xreq_subcall_req = hook_xreq_subcall_req_default_cb,
 381         .hook_xreq_subcall_req_result = hook_xreq_subcall_req_result_default_cb,
 382         .hook_xreq_has_permission = hook_xreq_has_permission_default_cb
 383 };
 384
 385 /******************************************************************************
 386  * section: hooks for tracing requests
 387  *****************************************************************************/
 388
 389 #define _HOOK_XREQ_(what,...)   \
 390         struct afb_hook_xreq *hook; \
 391         struct afb_hookid hookid; \
 392         pthread_rwlock_rdlock(&rwlock); \
 393         init_hookid(&hookid); \
 394         hook = list_of_xreq_hooks; \
 395         while (hook) { \
 396                 if (hook->itf->hook_xreq_##what \
 397                  && (hook->flags & afb_hook_flag_req_##what) != 0 \
 398                  && (!hook->session || hook->session == xreq->context.session) \
 399                  && (!hook->api || !strcasecmp(hook->api, xreq->api)) \
 400                  && (!hook->verb || !strcasecmp(hook->verb, xreq->verb))) { \
 401                         hook->itf->hook_xreq_##what(hook->closure, &hookid, __VA_ARGS__); \
 402                 } \
 403                 hook = hook->next; \
 404         } \
 405         pthread_rwlock_unlock(&rwlock);
 406
 407
 408 void afb_hook_xreq_begin(const struct afb_xreq *xreq)
 409 {
 410         _HOOK_XREQ_(begin, xreq);
 411 }
 412
 413 void afb_hook_xreq_end(const struct afb_xreq *xreq)
 414 {
 415         _HOOK_XREQ_(end, xreq);
 416 }
 417
 418 struct json_object *afb_hook_xreq_json(const struct afb_xreq *xreq, struct json_object *obj)
 419 {
 420         _HOOK_XREQ_(json, xreq, obj);
 421         return obj;
 422 }
 423
 424 struct afb_arg afb_hook_xreq_get(const struct afb_xreq *xreq, const char *name, struct afb_arg arg)
 425 {
 426         _HOOK_XREQ_(get, xreq, name, arg);
 427         return arg;
 428 }
 429
 430 void afb_hook_xreq_success(const struct afb_xreq *xreq, struct json_object *obj, const char *info)
 431 {
 432         _HOOK_XREQ_(success, xreq, obj, info);
 433 }
 434
 435 void afb_hook_xreq_fail(const struct afb_xreq *xreq, const char *status, const char *info)
 436 {
 437         _HOOK_XREQ_(fail, xreq, status, info);
 438 }
 439
 440 void *afb_hook_xreq_context_get(const struct afb_xreq *xreq, void *value)
 441 {
 442         _HOOK_XREQ_(context_get, xreq, value);
 443         return value;
 444 }
 445
 446 void afb_hook_xreq_context_set(const struct afb_xreq *xreq, void *value, void (*free_value)(void*))
 447 {
 448         _HOOK_XREQ_(context_set, xreq, value, free_value);
 449 }
 450
 451 void afb_hook_xreq_addref(const struct afb_xreq *xreq)
 452 {
 453         _HOOK_XREQ_(addref, xreq);
 454 }
 455
 456 void afb_hook_xreq_unref(const struct afb_xreq *xreq)
 457 {
 458         _HOOK_XREQ_(unref, xreq);
 459 }
 460
 461 void afb_hook_xreq_session_close(const struct afb_xreq *xreq)
 462 {
 463         _HOOK_XREQ_(session_close, xreq);
 464 }
 465
 466 int afb_hook_xreq_session_set_LOA(const struct afb_xreq *xreq, unsigned level, int result)
 467 {
 468         _HOOK_XREQ_(session_set_LOA, xreq, level, result);
 469         return result;
 470 }
 471
 472 int afb_hook_xreq_subscribe(const struct afb_xreq *xreq, struct afb_event event, int result)
 473 {
 474         _HOOK_XREQ_(subscribe, xreq, event, result);
 475         return result;
 476 }
 477
 478 int afb_hook_xreq_unsubscribe(const struct afb_xreq *xreq, struct afb_event event, int result)
 479 {
 480         _HOOK_XREQ_(unsubscribe, xreq, event, result);
 481         return result;
 482 }
 483
 484 void afb_hook_xreq_subcall(const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 485 {
 486         _HOOK_XREQ_(subcall, xreq, api, verb, args);
 487 }
 488
 489 void afb_hook_xreq_subcall_result(const struct afb_xreq *xreq, int status, struct json_object *result)
 490 {
 491         _HOOK_XREQ_(subcall_result, xreq, status, result);
 492 }
 493
 494 void afb_hook_xreq_subcallsync(const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 495 {
 496         _HOOK_XREQ_(subcallsync, xreq, api, verb, args);
 497 }
 498
 499 int afb_hook_xreq_subcallsync_result(const struct afb_xreq *xreq, int status, struct json_object *result)
 500 {
 501         _HOOK_XREQ_(subcallsync_result, xreq, status, result);
 502         return status;
 503 }
 504
 505 void afb_hook_xreq_vverbose(const struct afb_xreq *xreq, int level, const char *file, int line, const char *func, const char *fmt, va_list args)
 506 {
 507         _HOOK_XREQ_(vverbose, xreq, level, file ?: "?", line, func ?: "?", fmt, args);
 508 }
 509
 510 void afb_hook_xreq_store(const struct afb_xreq *xreq, struct afb_stored_req *sreq)
 511 {
 512         _HOOK_XREQ_(store, xreq, sreq);
 513 }
 514
 515 void afb_hook_xreq_unstore(const struct afb_xreq *xreq)
 516 {
 517         _HOOK_XREQ_(unstore, xreq);
 518 }
 519
 520 void afb_hook_xreq_subcall_req(const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 521 {
 522         _HOOK_XREQ_(subcall_req, xreq, api, verb, args);
 523 }
 524
 525 void afb_hook_xreq_subcall_req_result(const struct afb_xreq *xreq, int status, struct json_object *result)
 526 {
 527         _HOOK_XREQ_(subcall_req_result, xreq, status, result);
 528 }
 529
 530 int afb_hook_xreq_has_permission(const struct afb_xreq *xreq, const char *permission, int result)
 531 {
 532         _HOOK_XREQ_(has_permission, xreq, permission, result);
 533         return result;
 534 }
 535
 536 /******************************************************************************
 537  * section: hooking xreqs
 538  *****************************************************************************/
 539
 540 void afb_hook_init_xreq(struct afb_xreq *xreq)
 541 {
 542         static int reqindex;
 543
 544         int f, flags;
 545         int add;
 546         struct afb_hook_xreq *hook;
 547
 548         /* scan hook list to get the expected flags */
 549         flags = 0;
 550         pthread_rwlock_rdlock(&rwlock);
 551         hook = list_of_xreq_hooks;
 552         while (hook) {
 553                 f = hook->flags & afb_hook_flags_req_all;
 554                 add = f != 0
 555                    && (!hook->session || hook->session == xreq->context.session)
 556                    && (!hook->api || !strcasecmp(hook->api, xreq->api))
 557                    && (!hook->verb || !strcasecmp(hook->verb, xreq->verb));
 558                 if (add)
 559                         flags |= f;
 560                 hook = hook->next;
 561         }
 562         pthread_rwlock_unlock(&rwlock);
 563
 564         /* store the hooking data */
 565         xreq->hookflags = flags;
 566         if (flags) {
 567                 pthread_rwlock_wrlock(&rwlock);
 568                 if (++reqindex < 0)
 569                         reqindex = 1;
 570                 xreq->hookindex = reqindex;
 571                 pthread_rwlock_unlock(&rwlock);
 572         }
 573 }
 574
 575 struct afb_hook_xreq *afb_hook_create_xreq(const char *api, const char *verb, struct afb_session *session, int flags, struct afb_hook_xreq_itf *itf, void *closure)
 576 {
 577         struct afb_hook_xreq *hook;
 578
 579         /* alloc the result */
 580         hook = calloc(1, sizeof *hook);
 581         if (hook == NULL)
 582                 return NULL;
 583
 584         /* get a copy of the names */
 585         hook->api = api ? strdup(api) : NULL;
 586         hook->verb = verb ? strdup(verb) : NULL;
 587         if ((api && !hook->api) || (verb && !hook->verb)) {
 588                 free(hook->api);
 589                 free(hook->verb);
 590                 free(hook);
 591                 return NULL;
 592         }
 593
 594         /* initialise the rest */
 595         hook->session = session;
 596         if (session)
 597                 afb_session_addref(session);
 598         hook->refcount = 1;
 599         hook->flags = flags;
 600         hook->itf = itf ? itf : &hook_xreq_default_itf;
 601         hook->closure = closure;
 602
 603         /* record the hook */
 604         pthread_rwlock_wrlock(&rwlock);
 605         hook->next = list_of_xreq_hooks;
 606         list_of_xreq_hooks = hook;
 607         pthread_rwlock_unlock(&rwlock);
 608
 609         /* returns it */
 610         return hook;
 611 }
 612
 613 struct afb_hook_xreq *afb_hook_addref_xreq(struct afb_hook_xreq *hook)
 614 {
 615         pthread_rwlock_wrlock(&rwlock);
 616         hook->refcount++;
 617         pthread_rwlock_unlock(&rwlock);
 618         return hook;
 619 }
 620
 621 void afb_hook_unref_xreq(struct afb_hook_xreq *hook)
 622 {
 623         struct afb_hook_xreq **prv;
 624
 625         if (hook) {
 626                 pthread_rwlock_wrlock(&rwlock);
 627                 if (--hook->refcount)
 628                         hook = NULL;
 629                 else {
 630                         /* unlink */
 631                         prv = &list_of_xreq_hooks;
 632                         while (*prv && *prv != hook)
 633                                 prv = &(*prv)->next;
 634                         if(*prv)
 635                                 *prv = hook->next;
 636                 }
 637                 pthread_rwlock_unlock(&rwlock);
 638                 if (hook) {
 639                         /* free */
 640                         free(hook->api);
 641                         free(hook->verb);
 642                         if (hook->session)
 643                                 afb_session_unref(hook->session);
 644                         free(hook);
 645                 }
 646         }
 647 }
 648
 649 /******************************************************************************
 650  * section: default callbacks for tracing daemon interface
 651  *****************************************************************************/
 652
 653 static void _hook_ditf_(const struct afb_ditf *ditf, const char *format, ...)
 654 {
 655         va_list ap;
 656         va_start(ap, format);
 657         _hook_("ditf-%s", format, ap, ditf->api);
 658         va_end(ap);
 659 }
 660
 661 static void hook_ditf_event_broadcast_before_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, const char *name, struct json_object *object)
 662 {
 663         _hook_ditf_(ditf, "event_broadcast.before(%s, %s)....", name, json_object_to_json_string(object));
 664 }
 665
 666 static void hook_ditf_event_broadcast_after_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, const char *name, struct json_object *object, int result)
 667 {
 668         _hook_ditf_(ditf, "event_broadcast.after(%s, %s) -> %d", name, json_object_to_json_string(object), result);
 669 }
 670
 671 static void hook_ditf_get_event_loop_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, struct sd_event *result)
 672 {
 673         _hook_ditf_(ditf, "get_event_loop() -> %p", result);
 674 }
 675
 676 static void hook_ditf_get_user_bus_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, struct sd_bus *result)
 677 {
 678         _hook_ditf_(ditf, "get_user_bus() -> %p", result);
 679 }
 680
 681 static void hook_ditf_get_system_bus_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, struct sd_bus *result)
 682 {
 683         _hook_ditf_(ditf, "get_system_bus() -> %p", result);
 684 }
 685
 686 static void hook_ditf_vverbose_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, int level, const char *file, int line, const char *function, const char *fmt, va_list args)
 687 {
 688         int len;
 689         char *msg;
 690         va_list ap;
 691
 692         va_copy(ap, args);
 693         len = vasprintf(&msg, fmt, ap);
 694         va_end(ap);
 695
 696         if (len < 0)
 697                 _hook_ditf_(ditf, "vverbose(%d, %s, %d, %s) -> %s ? ? ?", level, file, line, function, fmt);
 698         else {
 699                 _hook_ditf_(ditf, "vverbose(%d, %s, %d, %s) -> %s", level, file, line, function, msg);
 700                 free(msg);
 701         }
 702 }
 703
 704 static void hook_ditf_event_make_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, const char *name, struct afb_event result)
 705 {
 706         _hook_ditf_(ditf, "event_make(%s) -> %s:%d", name, afb_evt_event_name(result), afb_evt_event_id(result));
 707 }
 708
 709 static void hook_ditf_rootdir_get_fd_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, int result)
 710 {
 711         char path[PATH_MAX];
 712         if (result < 0)
 713                 _hook_ditf_(ditf, "rootdir_get_fd() -> %d, %m", result);
 714         else {
 715                 sprintf(path, "/proc/self/fd/%d", result);
 716                 readlink(path, path, sizeof path);
 717                 _hook_ditf_(ditf, "rootdir_get_fd() -> %d = %s", result, path);
 718         }
 719 }
 720
 721 static void hook_ditf_rootdir_open_locale_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, const char *filename, int flags, const char *locale, int result)
 722 {
 723         char path[PATH_MAX];
 724         if (!locale)
 725                 locale = "(null)";
 726         if (result < 0)
 727                 _hook_ditf_(ditf, "rootdir_open_locale(%s, %d, %s) -> %d, %m", filename, flags, locale, result);
 728         else {
 729                 sprintf(path, "/proc/self/fd/%d", result);
 730                 readlink(path, path, sizeof path);
 731                 _hook_ditf_(ditf, "rootdir_open_locale(%s, %d, %s) -> %d = %s", filename, flags, locale, result, path);
 732         }
 733 }
 734
 735 static void hook_ditf_queue_job_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, void (*callback)(int signum, void *arg), void *argument, void *group, int timeout, int result)
 736 {
 737         _hook_ditf_(ditf, "queue_job(%p, %p, %p, %d) -> %d", callback, argument, group, timeout, result);
 738 }
 739
 740 static void hook_ditf_unstore_req_cb(void *closure, const struct afb_hookid *hookid,  const struct afb_ditf *ditf, struct afb_stored_req *sreq)
 741 {
 742         _hook_ditf_(ditf, "unstore_req(%p)", sreq);
 743 }
 744
 745 static void hook_ditf_require_api_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, const char *name, int initialized)
 746 {
 747         _hook_ditf_(ditf, "require_api(%s, %d)...", name, initialized);
 748 }
 749
 750 static void hook_ditf_require_api_result_cb(void *closure, const struct afb_hookid *hookid, const struct afb_ditf *ditf, const char *name, int initialized, int result)
 751 {
 752         _hook_ditf_(ditf, "...require_api(%s, %d) -> %d", name, initialized, result);
 753 }
 754
 755 static struct afb_hook_ditf_itf hook_ditf_default_itf = {
 756         .hook_ditf_event_broadcast_before = hook_ditf_event_broadcast_before_cb,
 757         .hook_ditf_event_broadcast_after = hook_ditf_event_broadcast_after_cb,
 758         .hook_ditf_get_event_loop = hook_ditf_get_event_loop_cb,
 759         .hook_ditf_get_user_bus = hook_ditf_get_user_bus_cb,
 760         .hook_ditf_get_system_bus = hook_ditf_get_system_bus_cb,
 761         .hook_ditf_vverbose = hook_ditf_vverbose_cb,
 762         .hook_ditf_event_make = hook_ditf_event_make_cb,
 763         .hook_ditf_rootdir_get_fd = hook_ditf_rootdir_get_fd_cb,
 764         .hook_ditf_rootdir_open_locale = hook_ditf_rootdir_open_locale_cb,
 765         .hook_ditf_queue_job = hook_ditf_queue_job_cb,
 766         .hook_ditf_unstore_req = hook_ditf_unstore_req_cb,
 767         .hook_ditf_require_api = hook_ditf_require_api_cb,
 768         .hook_ditf_require_api_result = hook_ditf_require_api_result_cb
 769 };
 770
 771 /******************************************************************************
 772  * section: hooks for tracing daemon interface (ditf)
 773  *****************************************************************************/
 774
 775 #define _HOOK_DITF_(what,...)   \
 776         struct afb_hook_ditf *hook; \
 777         struct afb_hookid hookid; \
 778         pthread_rwlock_rdlock(&rwlock); \
 779         init_hookid(&hookid); \
 780         hook = list_of_ditf_hooks; \
 781         while (hook) { \
 782                 if (hook->itf->hook_ditf_##what \
 783                  && (hook->flags & afb_hook_flag_ditf_##what) != 0 \
 784                  && (!hook->api || !strcasecmp(hook->api, ditf->api))) { \
 785                         hook->itf->hook_ditf_##what(hook->closure, &hookid, __VA_ARGS__); \
 786                 } \
 787                 hook = hook->next; \
 788         } \
 789         pthread_rwlock_unlock(&rwlock);
 790
 791 void afb_hook_ditf_event_broadcast_before(const struct afb_ditf *ditf, const char *name, struct json_object *object)
 792 {
 793         _HOOK_DITF_(event_broadcast_before, ditf, name, object);
 794 }
 795
 796 int afb_hook_ditf_event_broadcast_after(const struct afb_ditf *ditf, const char *name, struct json_object *object, int result)
 797 {
 798         _HOOK_DITF_(event_broadcast_after, ditf, name, object, result);
 799         return result;
 800 }
 801
 802 struct sd_event *afb_hook_ditf_get_event_loop(const struct afb_ditf *ditf, struct sd_event *result)
 803 {
 804         _HOOK_DITF_(get_event_loop, ditf, result);
 805         return result;
 806 }
 807
 808 struct sd_bus *afb_hook_ditf_get_user_bus(const struct afb_ditf *ditf, struct sd_bus *result)
 809 {
 810         _HOOK_DITF_(get_user_bus, ditf, result);
 811         return result;
 812 }
 813
 814 struct sd_bus *afb_hook_ditf_get_system_bus(const struct afb_ditf *ditf, struct sd_bus *result)
 815 {
 816         _HOOK_DITF_(get_system_bus, ditf, result);
 817         return result;
 818 }
 819
 820 void afb_hook_ditf_vverbose(const struct afb_ditf *ditf, int level, const char *file, int line, const char *function, const char *fmt, va_list args)
 821 {
 822         _HOOK_DITF_(vverbose, ditf, level, file, line, function, fmt, args);
 823 }
 824
 825 struct afb_event afb_hook_ditf_event_make(const struct afb_ditf *ditf, const char *name, struct afb_event result)
 826 {
 827         _HOOK_DITF_(event_make, ditf, name, result);
 828         return result;
 829 }
 830
 831 int afb_hook_ditf_rootdir_get_fd(const struct afb_ditf *ditf, int result)
 832 {
 833         _HOOK_DITF_(rootdir_get_fd, ditf, result);
 834         return result;
 835 }
 836
 837 int afb_hook_ditf_rootdir_open_locale(const struct afb_ditf *ditf, const char *filename, int flags, const char *locale, int result)
 838 {
 839         _HOOK_DITF_(rootdir_open_locale, ditf, filename, flags, locale, result);
 840         return result;
 841 }
 842
 843 int afb_hook_ditf_queue_job(const struct afb_ditf *ditf, void (*callback)(int signum, void *arg), void *argument, void *group, int timeout, int result)
 844 {
 845         _HOOK_DITF_(queue_job, ditf, callback, argument, group, timeout, result);
 846         return result;
 847 }
 848
 849 void afb_hook_ditf_unstore_req(const struct afb_ditf *ditf, struct afb_stored_req *sreq)
 850 {
 851         _HOOK_DITF_(unstore_req, ditf, sreq);
 852 }
 853
 854 void afb_hook_ditf_require_api(const struct afb_ditf *ditf, const char *name, int initialized)
 855 {
 856         _HOOK_DITF_(require_api, ditf, name, initialized);
 857 }
 858
 859 int afb_hook_ditf_require_api_result(const struct afb_ditf *ditf, const char *name, int initialized, int result)
 860 {
 861         _HOOK_DITF_(require_api_result, ditf, name, initialized, result);
 862         return result;
 863 }
 864
 865 /******************************************************************************
 866  * section: hooking ditf
 867  *****************************************************************************/
 868
 869 int afb_hook_flags_ditf(const char *api)
 870 {
 871         int flags;
 872         struct afb_hook_ditf *hook;
 873
 874         pthread_rwlock_rdlock(&rwlock);
 875         flags = 0;
 876         hook = list_of_ditf_hooks;
 877         while (hook) {
 878                 if (!api || !hook->api || !strcasecmp(hook->api, api))
 879                         flags |= hook->flags;
 880                 hook = hook->next;
 881         }
 882         pthread_rwlock_unlock(&rwlock);
 883         return flags;
 884 }
 885
 886 struct afb_hook_ditf *afb_hook_create_ditf(const char *api, int flags, struct afb_hook_ditf_itf *itf, void *closure)
 887 {
 888         struct afb_hook_ditf *hook;
 889
 890         /* alloc the result */
 891         hook = calloc(1, sizeof *hook);
 892         if (hook == NULL)
 893                 return NULL;
 894
 895         /* get a copy of the names */
 896         hook->api = api ? strdup(api) : NULL;
 897         if (api && !hook->api) {
 898                 free(hook);
 899                 return NULL;
 900         }
 901
 902         /* initialise the rest */
 903         hook->refcount = 1;
 904         hook->flags = flags;
 905         hook->itf = itf ? itf : &hook_ditf_default_itf;
 906         hook->closure = closure;
 907
 908         /* record the hook */
 909         pthread_rwlock_wrlock(&rwlock);
 910         hook->next = list_of_ditf_hooks;
 911         list_of_ditf_hooks = hook;
 912         pthread_rwlock_unlock(&rwlock);
 913
 914         /* returns it */
 915         return hook;
 916 }
 917
 918 struct afb_hook_ditf *afb_hook_addref_ditf(struct afb_hook_ditf *hook)
 919 {
 920         pthread_rwlock_wrlock(&rwlock);
 921         hook->refcount++;
 922         pthread_rwlock_unlock(&rwlock);
 923         return hook;
 924 }
 925
 926 void afb_hook_unref_ditf(struct afb_hook_ditf *hook)
 927 {
 928         struct afb_hook_ditf **prv;
 929
 930         if (hook) {
 931                 pthread_rwlock_wrlock(&rwlock);
 932                 if (--hook->refcount)
 933                         hook = NULL;
 934                 else {
 935                         /* unlink */
 936                         prv = &list_of_ditf_hooks;
 937                         while (*prv && *prv != hook)
 938                                 prv = &(*prv)->next;
 939                         if(*prv)
 940                                 *prv = hook->next;
 941                 }
 942                 pthread_rwlock_unlock(&rwlock);
 943                 if (hook) {
 944                         /* free */
 945                         free(hook->api);
 946                         free(hook);
 947                 }
 948         }
 949 }
 950
 951 /******************************************************************************
 952  * section: default callbacks for tracing service interface (svc)
 953  *****************************************************************************/
 954
 955 static void _hook_svc_(const struct afb_svc *svc, const char *format, ...)
 956 {
 957         va_list ap;
 958         va_start(ap, format);
 959         _hook_("svc-%s", format, ap, svc->api);
 960         va_end(ap);
 961 }
 962
 963 static void hook_svc_start_before_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc)
 964 {
 965         _hook_svc_(svc, "start.before");
 966 }
 967
 968 static void hook_svc_start_after_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc, int status)
 969 {
 970         _hook_svc_(svc, "start.after -> %d", status);
 971 }
 972
 973 static void hook_svc_on_event_before_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc, const char *event, int eventid, struct json_object *object)
 974 {
 975         _hook_svc_(svc, "on_event.before(%s, %d, %s)", event, eventid, json_object_to_json_string(object));
 976 }
 977
 978 static void hook_svc_on_event_after_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc, const char *event, int eventid, struct json_object *object)
 979 {
 980         _hook_svc_(svc, "on_event.after(%s, %d, %s)", event, eventid, json_object_to_json_string(object));
 981 }
 982
 983 static void hook_svc_call_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc, const char *api, const char *verb, struct json_object *args)
 984 {
 985         _hook_svc_(svc, "call(%s/%s, %s) ...", api, verb, json_object_to_json_string(args));
 986 }
 987
 988 static void hook_svc_call_result_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc, int status, struct json_object *result)
 989 {
 990         _hook_svc_(svc, "    ...call... -> %d: %s", status, json_object_to_json_string(result));
 991 }
 992
 993 static void hook_svc_callsync_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc, const char *api, const char *verb, struct json_object *args)
 994 {
 995         _hook_svc_(svc, "callsync(%s/%s, %s) ...", api, verb, json_object_to_json_string(args));
 996 }
 997
 998 static void hook_svc_callsync_result_default_cb(void *closure, const struct afb_hookid *hookid, const struct afb_svc *svc, int status, struct json_object *result)
 999 {
1000         _hook_svc_(svc, "    ...callsync... -> %d: %s", status, json_object_to_json_string(result));
1001 }
1002
1003 static struct afb_hook_svc_itf hook_svc_default_itf = {
1004         .hook_svc_start_before = hook_svc_start_before_default_cb,
1005         .hook_svc_start_after = hook_svc_start_after_default_cb,
1006         .hook_svc_on_event_before = hook_svc_on_event_before_default_cb,
1007         .hook_svc_on_event_after = hook_svc_on_event_after_default_cb,
1008         .hook_svc_call = hook_svc_call_default_cb,
1009         .hook_svc_call_result = hook_svc_call_result_default_cb,
1010         .hook_svc_callsync = hook_svc_callsync_default_cb,
1011         .hook_svc_callsync_result = hook_svc_callsync_result_default_cb
1012 };
1013
1014 /******************************************************************************
1015  * section: hooks for tracing service interface (svc)
1016  *****************************************************************************/
1017
1018 #define _HOOK_SVC_(what,...)   \
1019         struct afb_hook_svc *hook; \
1020         struct afb_hookid hookid; \
1021         pthread_rwlock_rdlock(&rwlock); \
1022         init_hookid(&hookid); \
1023         hook = list_of_svc_hooks; \
1024         while (hook) { \
1025                 if (hook->itf->hook_svc_##what \
1026                  && (hook->flags & afb_hook_flag_svc_##what) != 0 \
1027                  && (!hook->api || !strcasecmp(hook->api, svc->api))) { \
1028                         hook->itf->hook_svc_##what(hook->closure, &hookid, __VA_ARGS__); \
1029                 } \
1030                 hook = hook->next; \
1031         } \
1032         pthread_rwlock_unlock(&rwlock);
1033
1034 void afb_hook_svc_start_before(const struct afb_svc *svc)
1035 {
1036         _HOOK_SVC_(start_before, svc);
1037 }
1038
1039 int afb_hook_svc_start_after(const struct afb_svc *svc, int status)
1040 {
1041         _HOOK_SVC_(start_after, svc, status);
1042         return status;
1043 }
1044
1045 void afb_hook_svc_on_event_before(const struct afb_svc *svc, const char *event, int eventid, struct json_object *object)
1046 {
1047         _HOOK_SVC_(on_event_before, svc, event, eventid, object);
1048 }
1049
1050 void afb_hook_svc_on_event_after(const struct afb_svc *svc, const char *event, int eventid, struct json_object *object)
1051 {
1052         _HOOK_SVC_(on_event_after, svc, event, eventid, object);
1053 }
1054
1055 void afb_hook_svc_call(const struct afb_svc *svc, const char *api, const char *verb, struct json_object *args)
1056 {
1057         _HOOK_SVC_(call, svc, api, verb, args);
1058 }
1059
1060 void afb_hook_svc_call_result(const struct afb_svc *svc, int status, struct json_object *result)
1061 {
1062         _HOOK_SVC_(call_result, svc, status, result);
1063 }
1064
1065 void afb_hook_svc_callsync(const struct afb_svc *svc, const char *api, const char *verb, struct json_object *args)
1066 {
1067         _HOOK_SVC_(callsync, svc, api, verb, args);
1068 }
1069
1070 int afb_hook_svc_callsync_result(const struct afb_svc *svc, int status, struct json_object *result)
1071 {
1072         _HOOK_SVC_(callsync_result, svc, status, result);
1073         return status;
1074 }
1075
1076 /******************************************************************************
1077  * section: hooking services (svc)
1078  *****************************************************************************/
1079
1080 int afb_hook_flags_svc(const char *api)
1081 {
1082         int flags;
1083         struct afb_hook_svc *hook;
1084
1085         pthread_rwlock_rdlock(&rwlock);
1086         flags = 0;
1087         hook = list_of_svc_hooks;
1088         while (hook) {
1089                 if (!api || !hook->api || !strcasecmp(hook->api, api))
1090                         flags |= hook->flags;
1091                 hook = hook->next;
1092         }
1093         pthread_rwlock_unlock(&rwlock);
1094         return flags;
1095 }
1096
1097 struct afb_hook_svc *afb_hook_create_svc(const char *api, int flags, struct afb_hook_svc_itf *itf, void *closure)
1098 {
1099         struct afb_hook_svc *hook;
1100
1101         /* alloc the result */
1102         hook = calloc(1, sizeof *hook);
1103         if (hook == NULL)
1104                 return NULL;
1105
1106         /* get a copy of the names */
1107         hook->api = api ? strdup(api) : NULL;
1108         if (api && !hook->api) {
1109                 free(hook);
1110                 return NULL;
1111         }
1112
1113         /* initialise the rest */
1114         hook->refcount = 1;
1115         hook->flags = flags;
1116         hook->itf = itf ? itf : &hook_svc_default_itf;
1117         hook->closure = closure;
1118
1119         /* record the hook */
1120         pthread_rwlock_wrlock(&rwlock);
1121         hook->next = list_of_svc_hooks;
1122         list_of_svc_hooks = hook;
1123         pthread_rwlock_unlock(&rwlock);
1124
1125         /* returns it */
1126         return hook;
1127 }
1128
1129 struct afb_hook_svc *afb_hook_addref_svc(struct afb_hook_svc *hook)
1130 {
1131         pthread_rwlock_wrlock(&rwlock);
1132         hook->refcount++;
1133         pthread_rwlock_unlock(&rwlock);
1134         return hook;
1135 }
1136
1137 void afb_hook_unref_svc(struct afb_hook_svc *hook)
1138 {
1139         struct afb_hook_svc **prv;
1140
1141         if (hook) {
1142                 pthread_rwlock_wrlock(&rwlock);
1143                 if (--hook->refcount)
1144                         hook = NULL;
1145                 else {
1146                         /* unlink */
1147                         prv = &list_of_svc_hooks;
1148                         while (*prv && *prv != hook)
1149                                 prv = &(*prv)->next;
1150                         if(*prv)
1151                                 *prv = hook->next;
1152                 }
1153                 pthread_rwlock_unlock(&rwlock);
1154                 if (hook) {
1155                         /* free */
1156                         free(hook->api);
1157                         free(hook);
1158                 }
1159         }
1160 }
1161
1162 /******************************************************************************
1163  * section: default callbacks for tracing service interface (evt)
1164  *****************************************************************************/
1165
1166 static void _hook_evt_(const char *evt, int id, const char *format, ...)
1167 {
1168         va_list ap;
1169         va_start(ap, format);
1170         _hook_("evt-%s:%d", format, ap, evt, id);
1171         va_end(ap);
1172 }
1173
1174 static void hook_evt_create_default_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1175 {
1176         _hook_evt_(evt, id, "create");
1177 }
1178
1179 static void hook_evt_push_before_default_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj)
1180 {
1181         _hook_evt_(evt, id, "push.before(%s)", json_object_to_json_string(obj));
1182 }
1183
1184
1185 static void hook_evt_push_after_default_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj, int result)
1186 {
1187         _hook_evt_(evt, id, "push.after(%s) -> %d", json_object_to_json_string(obj), result);
1188 }
1189
1190 static void hook_evt_broadcast_before_default_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj)
1191 {
1192         _hook_evt_(evt, id, "broadcast.before(%s)", json_object_to_json_string(obj));
1193 }
1194
1195 static void hook_evt_broadcast_after_default_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj, int result)
1196 {
1197         _hook_evt_(evt, id, "broadcast.after(%s) -> %d", json_object_to_json_string(obj), result);
1198 }
1199
1200 static void hook_evt_name_default_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1201 {
1202         _hook_evt_(evt, id, "name");
1203 }
1204
1205 static void hook_evt_drop_default_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1206 {
1207         _hook_evt_(evt, id, "drop");
1208 }
1209
1210 static struct afb_hook_evt_itf hook_evt_default_itf = {
1211         .hook_evt_create = hook_evt_create_default_cb,
1212         .hook_evt_push_before = hook_evt_push_before_default_cb,
1213         .hook_evt_push_after = hook_evt_push_after_default_cb,
1214         .hook_evt_broadcast_before = hook_evt_broadcast_before_default_cb,
1215         .hook_evt_broadcast_after = hook_evt_broadcast_after_default_cb,
1216         .hook_evt_name = hook_evt_name_default_cb,
1217         .hook_evt_drop = hook_evt_drop_default_cb
1218 };
1219
1220 /******************************************************************************
1221  * section: hooks for tracing events interface (evt)
1222  *****************************************************************************/
1223
1224 #define _HOOK_EVT_(what,...)   \
1225         struct afb_hook_evt *hook; \
1226         struct afb_hookid hookid; \
1227         pthread_rwlock_rdlock(&rwlock); \
1228         init_hookid(&hookid); \
1229         hook = list_of_evt_hooks; \
1230         while (hook) { \
1231                 if (hook->itf->hook_evt_##what \
1232                  && (hook->flags & afb_hook_flag_evt_##what) != 0 \
1233                  && (!hook->pattern || !fnmatch(hook->pattern, evt, FNM_CASEFOLD))) { \
1234                         hook->itf->hook_evt_##what(hook->closure, &hookid, __VA_ARGS__); \
1235                 } \
1236                 hook = hook->next; \
1237         } \
1238         pthread_rwlock_unlock(&rwlock);
1239
1240 void afb_hook_evt_create(const char *evt, int id)
1241 {
1242         _HOOK_EVT_(create, evt, id);
1243 }
1244
1245 void afb_hook_evt_push_before(const char *evt, int id, struct json_object *obj)
1246 {
1247         _HOOK_EVT_(push_before, evt, id, obj);
1248 }
1249
1250 int afb_hook_evt_push_after(const char *evt, int id, struct json_object *obj, int result)
1251 {
1252         _HOOK_EVT_(push_after, evt, id, obj, result);
1253         return result;
1254 }
1255
1256 void afb_hook_evt_broadcast_before(const char *evt, int id, struct json_object *obj)
1257 {
1258         _HOOK_EVT_(broadcast_before, evt, id, obj);
1259 }
1260
1261 int afb_hook_evt_broadcast_after(const char *evt, int id, struct json_object *obj, int result)
1262 {
1263         _HOOK_EVT_(broadcast_after, evt, id, obj, result);
1264         return result;
1265 }
1266
1267 void afb_hook_evt_name(const char *evt, int id)
1268 {
1269         _HOOK_EVT_(name, evt, id);
1270 }
1271
1272 void afb_hook_evt_drop(const char *evt, int id)
1273 {
1274         _HOOK_EVT_(drop, evt, id);
1275 }
1276
1277 /******************************************************************************
1278  * section: hooking services (evt)
1279  *****************************************************************************/
1280
1281 int afb_hook_flags_evt(const char *name)
1282 {
1283         int flags;
1284         struct afb_hook_evt *hook;
1285
1286         pthread_rwlock_rdlock(&rwlock);
1287         flags = 0;
1288         hook = list_of_evt_hooks;
1289         while (hook) {
1290                 if (!name || !hook->pattern || !fnmatch(hook->pattern, name, FNM_CASEFOLD))
1291                         flags |= hook->flags;
1292                 hook = hook->next;
1293         }
1294         pthread_rwlock_unlock(&rwlock);
1295         return flags;
1296 }
1297
1298 struct afb_hook_evt *afb_hook_create_evt(const char *pattern, int flags, struct afb_hook_evt_itf *itf, void *closure)
1299 {
1300         struct afb_hook_evt *hook;
1301
1302         /* alloc the result */
1303         hook = calloc(1, sizeof *hook);
1304         if (hook == NULL)
1305                 return NULL;
1306
1307         /* get a copy of the names */
1308         hook->pattern = pattern ? strdup(pattern) : NULL;
1309         if (pattern && !hook->pattern) {
1310                 free(hook);
1311                 return NULL;
1312         }
1313
1314         /* initialise the rest */
1315         hook->refcount = 1;
1316         hook->flags = flags;
1317         hook->itf = itf ? itf : &hook_evt_default_itf;
1318         hook->closure = closure;
1319
1320         /* record the hook */
1321         pthread_rwlock_wrlock(&rwlock);
1322         hook->next = list_of_evt_hooks;
1323         list_of_evt_hooks = hook;
1324         pthread_rwlock_unlock(&rwlock);
1325
1326         /* returns it */
1327         return hook;
1328 }
1329
1330 struct afb_hook_evt *afb_hook_addref_evt(struct afb_hook_evt *hook)
1331 {
1332         pthread_rwlock_wrlock(&rwlock);
1333         hook->refcount++;
1334         pthread_rwlock_unlock(&rwlock);
1335         return hook;
1336 }
1337
1338 void afb_hook_unref_evt(struct afb_hook_evt *hook)
1339 {
1340         struct afb_hook_evt **prv;
1341
1342         if (hook) {
1343                 pthread_rwlock_wrlock(&rwlock);
1344                 if (--hook->refcount)
1345                         hook = NULL;
1346                 else {
1347                         /* unlink */
1348                         prv = &list_of_evt_hooks;
1349                         while (*prv && *prv != hook)
1350                                 prv = &(*prv)->next;
1351                         if(*prv)
1352                                 *prv = hook->next;
1353                 }
1354                 pthread_rwlock_unlock(&rwlock);
1355                 if (hook) {
1356                         /* free */
1357                         free(hook->pattern);
1358                         free(hook);
1359                 }
1360         }
1361 }
1362
1363 /******************************************************************************
1364  * section: default callbacks for globals (global)
1365  *****************************************************************************/
1366
1367 static void _hook_global_(const char *format, ...)
1368 {
1369         va_list ap;
1370         va_start(ap, format);
1371         _hook_("global", format, ap);
1372         va_end(ap);
1373 }
1374
1375 static void hook_global_vverbose_default_cb(void *closure, const struct afb_hookid *hookid, int level, const char *file, int line, const char *func, const char *fmt, va_list args)
1376 {
1377         int len;
1378         char *msg;
1379         va_list ap;
1380
1381         va_copy(ap, args);
1382         len = vasprintf(&msg, fmt, ap);
1383         va_end(ap);
1384
1385         if (len < 0)
1386                 _hook_global_("vverbose(%d, %s, %d, %s) -> %s ? ? ?", level, file, line, func, fmt);
1387         else {
1388                 _hook_global_("vverbose(%d, %s, %d, %s) -> %s", level, file, line, func, msg);
1389                 free(msg);
1390         }
1391 }
1392
1393 static struct afb_hook_global_itf hook_global_default_itf = {
1394         .hook_global_vverbose = hook_global_vverbose_default_cb
1395 };
1396
1397 /******************************************************************************
1398  * section: hooks for tracing globals (global)
1399  *****************************************************************************/
1400
1401 #define _HOOK_GLOBAL_(what,...)   \
1402         struct afb_hook_global *hook; \
1403         struct afb_hookid hookid; \
1404         pthread_rwlock_rdlock(&rwlock); \
1405         init_hookid(&hookid); \
1406         hook = list_of_global_hooks; \
1407         while (hook) { \
1408                 if (hook->itf->hook_global_##what \
1409                  && (hook->flags & afb_hook_flag_global_##what) != 0) { \
1410                         hook->itf->hook_global_##what(hook->closure, &hookid, __VA_ARGS__); \
1411                 } \
1412                 hook = hook->next; \
1413         } \
1414         pthread_rwlock_unlock(&rwlock);
1415
1416 static void afb_hook_global_vverbose(int level, const char *file, int line, const char *func, const char *fmt, va_list args)
1417 {
1418         _HOOK_GLOBAL_(vverbose, level, file ?: "?", line, func ?: "?", fmt, args);
1419 }
1420
1421 /******************************************************************************
1422  * section: hooking globals (global)
1423  *****************************************************************************/
1424
1425 static void update_global()
1426 {
1427         struct afb_hook_global *hook;
1428         int flags = 0;
1429
1430         pthread_rwlock_rdlock(&rwlock);
1431         hook = list_of_global_hooks;
1432         while (hook) {
1433                 flags = hook->flags;
1434                 hook = hook->next;
1435         }
1436         verbose_observer = (flags & afb_hook_flag_global_vverbose) ? afb_hook_global_vverbose : NULL;
1437         pthread_rwlock_unlock(&rwlock);
1438 }
1439
1440 struct afb_hook_global *afb_hook_create_global(int flags, struct afb_hook_global_itf *itf, void *closure)
1441 {
1442         struct afb_hook_global *hook;
1443
1444         /* alloc the result */
1445         hook = calloc(1, sizeof *hook);
1446         if (hook == NULL)
1447                 return NULL;
1448
1449         /* initialise the rest */
1450         hook->refcount = 1;
1451         hook->flags = flags;
1452         hook->itf = itf ? itf : &hook_global_default_itf;
1453         hook->closure = closure;
1454
1455         /* record the hook */
1456         pthread_rwlock_wrlock(&rwlock);
1457         hook->next = list_of_global_hooks;
1458         list_of_global_hooks = hook;
1459         pthread_rwlock_unlock(&rwlock);
1460
1461         /* update hooking */
1462         update_global();
1463
1464         /* returns it */
1465         return hook;
1466 }
1467
1468 struct afb_hook_global *afb_hook_addref_global(struct afb_hook_global *hook)
1469 {
1470         pthread_rwlock_wrlock(&rwlock);
1471         hook->refcount++;
1472         pthread_rwlock_unlock(&rwlock);
1473         return hook;
1474 }
1475
1476 void afb_hook_unref_global(struct afb_hook_global *hook)
1477 {
1478         struct afb_hook_global **prv;
1479
1480         if (hook) {
1481                 pthread_rwlock_wrlock(&rwlock);
1482                 if (--hook->refcount)
1483                         hook = NULL;
1484                 else {
1485                         /* unlink */
1486                         prv = &list_of_global_hooks;
1487                         while (*prv && *prv != hook)
1488                                 prv = &(*prv)->next;
1489                         if(*prv)
1490                                 *prv = hook->next;
1491                 }
1492                 pthread_rwlock_unlock(&rwlock);
1493                 if (hook) {
1494                         /* free */
1495                         free(hook);
1496
1497                         /* update hooking */
1498                         update_global();
1499                 }
1500         }
1501 }
1502