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