src/afb-hook.c

   1 /*
   2  * Copyright (C) 2016, 2017, 2018 "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 <sys/uio.h>
  27
  28 #include <json-c/json.h>
  29 #if !defined(JSON_C_TO_STRING_NOSLASHESCAPE)
  30 #define JSON_C_TO_STRING_NOSLASHESCAPE 0
  31 #endif
  32
  33 #include <afb/afb-req-x1.h>
  34 #include <afb/afb-event-x2.h>
  35
  36 #include "afb-context.h"
  37 #include "afb-hook.h"
  38 #include "afb-session.h"
  39 #include "afb-cred.h"
  40 #include "afb-xreq.h"
  41 #include "afb-export.h"
  42 #include "afb-evt.h"
  43 #include "afb-api.h"
  44 #include "afb-msg-json.h"
  45 #include "verbose.h"
  46
  47 #include <fnmatch.h>
  48 #define MATCH(pattern,string)   (\
  49                 pattern \
  50                         ? !fnmatch((pattern),(string),FNM_CASEFOLD|FNM_EXTMATCH|FNM_PERIOD) \
  51                         : afb_api_is_public(string))
  52
  53 #define MATCH_API(pattern,string)       MATCH(pattern,string)
  54 #define MATCH_VERB(pattern,string)      MATCH(pattern,string)
  55 #define MATCH_EVENT(pattern,string)     MATCH(pattern,string)
  56 #define MATCH_SESSION(pattern,string)   MATCH(pattern,string)
  57
  58 /**
  59  * Definition of a hook for xreq
  60  */
  61 struct afb_hook_xreq {
  62         struct afb_hook_xreq *next; /**< next hook */
  63         unsigned refcount; /**< reference count */
  64         unsigned flags; /**< hook flags */
  65         char *api; /**< api hooked or NULL for any */
  66         char *verb; /**< verb hooked or NULL for any */
  67         struct afb_session *session; /**< session hooked or NULL if any */
  68         struct afb_hook_xreq_itf *itf; /**< interface of hook */
  69         void *closure; /**< closure for callbacks */
  70 };
  71
  72 /**
  73  * Definition of a hook for export
  74  */
  75 struct afb_hook_api {
  76         struct afb_hook_api *next; /**< next hook */
  77         unsigned refcount; /**< reference count */
  78         unsigned flags; /**< hook flags */
  79         char *api; /**< api hooked or NULL for any */
  80         struct afb_hook_api_itf *itf; /**< interface of hook */
  81         void *closure; /**< closure for callbacks */
  82 };
  83
  84 /**
  85  * Definition of a hook for evt
  86  */
  87 struct afb_hook_evt {
  88         struct afb_hook_evt *next; /**< next hook */
  89         unsigned refcount; /**< reference count */
  90         unsigned flags; /**< hook flags */
  91         char *pattern; /**< event pattern name hooked or NULL for any */
  92         struct afb_hook_evt_itf *itf; /**< interface of hook */
  93         void *closure; /**< closure for callbacks */
  94 };
  95
  96 /**
  97  * Definition of a hook for session
  98  */
  99 struct afb_hook_session {
 100         struct afb_hook_session *next; /**< next hook */
 101         unsigned refcount; /**< reference count */
 102         unsigned flags; /**< hook flags */
 103         char *pattern; /**< event pattern name hooked or NULL for any */
 104         struct afb_hook_session_itf *itf; /**< interface of hook */
 105         void *closure; /**< closure for callbacks */
 106 };
 107
 108 /**
 109  * Definition of a hook for global
 110  */
 111 struct afb_hook_global {
 112         struct afb_hook_global *next; /**< next hook */
 113         unsigned refcount; /**< reference count */
 114         unsigned flags; /**< hook flags */
 115         struct afb_hook_global_itf *itf; /**< interface of hook */
 116         void *closure; /**< closure for callbacks */
 117 };
 118
 119 /* synchronization across threads */
 120 static pthread_rwlock_t rwlock = PTHREAD_RWLOCK_INITIALIZER;
 121 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 122
 123 /* list of hooks for xreq */
 124 static struct afb_hook_xreq *list_of_xreq_hooks = NULL;
 125
 126 /* list of hooks for export */
 127 static struct afb_hook_api *list_of_api_hooks = NULL;
 128
 129 /* list of hooks for evt */
 130 static struct afb_hook_evt *list_of_evt_hooks = NULL;
 131
 132 /* list of hooks for session */
 133 static struct afb_hook_session *list_of_session_hooks = NULL;
 134
 135 /* list of hooks for global */
 136 static struct afb_hook_global *list_of_global_hooks = NULL;
 137
 138 /* hook id */
 139 static unsigned next_hookid = 0;
 140
 141 /******************************************************************************
 142  * section: hook id
 143  *****************************************************************************/
 144 static void init_hookid(struct afb_hookid *hookid)
 145 {
 146         hookid->id = __atomic_add_fetch(&next_hookid, 1, __ATOMIC_RELAXED);
 147         clock_gettime(CLOCK_REALTIME, &hookid->time);
 148 }
 149
 150 /******************************************************************************
 151  * section: default callbacks for tracing requests
 152  *****************************************************************************/
 153
 154 static char *_pbuf_(const char *fmt, va_list args, char **palloc, char *sbuf, size_t szsbuf, size_t *outlen)
 155 {
 156         int rc;
 157         va_list cp;
 158
 159         *palloc = NULL;
 160         va_copy(cp, args);
 161         rc = vsnprintf(sbuf, szsbuf, fmt, args);
 162         if ((size_t)rc >= szsbuf) {
 163                 sbuf[szsbuf-1] = 0;
 164                 sbuf[szsbuf-2] = sbuf[szsbuf-3] = sbuf[szsbuf-4] = '.';
 165                 rc = vasprintf(palloc, fmt, cp);
 166                 if (rc >= 0)
 167                         sbuf = *palloc;
 168         }
 169         va_end(cp);
 170         if (rc >= 0 && outlen)
 171                 *outlen = (size_t)rc;
 172         return sbuf;
 173 }
 174
 175 static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...)
 176 {
 177         static const char chars[] = "HOOK: [] \n";
 178         char *mem1, *mem2, buf1[256], buf2[2000];
 179         struct iovec iov[5];
 180         va_list arg1;
 181
 182         /* "HOOK: [" */
 183         iov[0].iov_base = (void*)&chars[0];
 184         iov[0].iov_len = 7;
 185
 186         /* fmt1 ... */
 187         va_start(arg1, arg2);
 188         iov[1].iov_base = _pbuf_(fmt1, arg1, &mem1, buf1, sizeof buf1, &iov[1].iov_len);
 189         va_end(arg1);
 190
 191         /* "] " */
 192         iov[2].iov_base = (void*)&chars[7];
 193         iov[2].iov_len = 2;
 194
 195         /* fmt2 arg2 */
 196         iov[3].iov_base = _pbuf_(fmt2, arg2, &mem2, buf2, sizeof buf2, &iov[3].iov_len);
 197
 198         /* "\n" */
 199         iov[4].iov_base = (void*)&chars[9];
 200         iov[4].iov_len = 1;
 201
 202         (void)writev(2, iov, 5);
 203
 204         free(mem1);
 205         free(mem2);
 206 }
 207
 208 static void _hook_xreq_(const struct afb_xreq *xreq, const char *format, ...)
 209 {
 210         va_list ap;
 211         va_start(ap, format);
 212         _hook_("xreq-%06d:%s/%s", format, ap, xreq->hookindex, xreq->request.called_api, xreq->request.called_verb);
 213         va_end(ap);
 214 }
 215
 216 static void hook_xreq_begin_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 217 {
 218         if (!xreq->cred)
 219                 _hook_xreq_(xreq, "BEGIN");
 220         else
 221                 _hook_xreq_(xreq, "BEGIN uid=%d=%s gid=%d pid=%d label=%s id=%s",
 222                         (int)xreq->cred->uid,
 223                         xreq->cred->user,
 224                         (int)xreq->cred->gid,
 225                         (int)xreq->cred->pid,
 226                         xreq->cred->label?:"(null)",
 227                         xreq->cred->id?:"(null)"
 228                 );
 229 }
 230
 231 static void hook_xreq_end_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 232 {
 233         _hook_xreq_(xreq, "END");
 234 }
 235
 236 static void hook_xreq_json_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *obj)
 237 {
 238         _hook_xreq_(xreq, "json() -> %s", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE));
 239 }
 240
 241 static void hook_xreq_get_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *name, struct afb_arg arg)
 242 {
 243         _hook_xreq_(xreq, "get(%s) -> { name: %s, value: %s, path: %s }", name, arg.name, arg.value, arg.path);
 244 }
 245
 246 static void hook_xreq_reply_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *obj, const char *error, const char *info)
 247 {
 248         _hook_xreq_(xreq, "reply[%s](%s, %s)", error?:"success", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE), info);
 249 }
 250
 251 static void hook_xreq_legacy_context_get_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, void *value)
 252 {
 253         _hook_xreq_(xreq, "context_get() -> %p", value);
 254 }
 255
 256 static void hook_xreq_legacy_context_set_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, void *value, void (*free_value)(void*))
 257 {
 258         _hook_xreq_(xreq, "context_set(%p, %p)", value, free_value);
 259 }
 260
 261 static void hook_xreq_addref_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 262 {
 263         _hook_xreq_(xreq, "addref()");
 264 }
 265
 266 static void hook_xreq_unref_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 267 {
 268         _hook_xreq_(xreq, "unref()");
 269 }
 270
 271 static void hook_xreq_session_close_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 272 {
 273         _hook_xreq_(xreq, "session_close()");
 274 }
 275
 276 static void hook_xreq_session_set_LOA_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, unsigned level, int result)
 277 {
 278         _hook_xreq_(xreq, "session_set_LOA(%u) -> %d", level, result);
 279 }
 280
 281 static void hook_xreq_subscribe_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_event_x2 *event_x2, int result)
 282 {
 283         _hook_xreq_(xreq, "subscribe(%s:%d) -> %d", afb_evt_event_x2_fullname(event_x2), afb_evt_event_x2_id(event_x2), result);
 284 }
 285
 286 static void hook_xreq_unsubscribe_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_event_x2 *event_x2, int result)
 287 {
 288         _hook_xreq_(xreq, "unsubscribe(%s:%d) -> %d", afb_evt_event_x2_fullname(event_x2), afb_evt_event_x2_id(event_x2), result);
 289 }
 290
 291 static void hook_xreq_subcall_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 292 {
 293         _hook_xreq_(xreq, "subcall(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 294 }
 295
 296 static void hook_xreq_subcall_result_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *object, const char *error, const char *info)
 297 {
 298         _hook_xreq_(xreq, "    ...subcall... [%s] -> %s (%s)", error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 299 }
 300
 301 static void hook_xreq_subcallsync_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args)
 302 {
 303         _hook_xreq_(xreq, "subcallsync(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 304 }
 305
 306 static void hook_xreq_subcallsync_result_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int status, struct json_object *object, const char *error, const char *info)
 307 {
 308         _hook_xreq_(xreq, "    ...subcallsync... %d [%s] -> %s (%s)", status, error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 309 }
 310
 311 static void hook_xreq_vverbose_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)
 312 {
 313         int len;
 314         char *msg;
 315         va_list ap;
 316
 317         va_copy(ap, args);
 318         len = vasprintf(&msg, fmt, ap);
 319         va_end(ap);
 320
 321         if (len < 0)
 322                 _hook_xreq_(xreq, "vverbose(%d:%s, %s, %d, %s) -> %s ? ? ?", level, verbose_name_of_level(level), file, line, func, fmt);
 323         else {
 324                 _hook_xreq_(xreq, "vverbose(%d:%s, %s, %d, %s) -> %s", level, verbose_name_of_level(level), file, line, func, msg);
 325                 free(msg);
 326         }
 327 }
 328
 329 static void hook_xreq_legacy_store_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_stored_req *sreq)
 330 {
 331         _hook_xreq_(xreq, "store() -> %p", sreq);
 332 }
 333
 334 static void hook_xreq_legacy_unstore_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 335 {
 336         _hook_xreq_(xreq, "unstore()");
 337 }
 338
 339 static void hook_xreq_has_permission_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *permission, int result)
 340 {
 341         _hook_xreq_(xreq, "has_permission(%s) -> %d", permission, result);
 342 }
 343
 344 static void hook_xreq_get_application_id_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, char *result)
 345 {
 346         _hook_xreq_(xreq, "get_application_id() -> %s", result);
 347 }
 348
 349 static void hook_xreq_context_make_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int replace, void *(*create_value)(void*), void (*free_value)(void*), void *create_closure, void *result)
 350 {
 351         _hook_xreq_(xreq, "context_make(replace=%s, %p, %p, %p) -> %p", replace?"yes":"no", create_value, free_value, create_closure, result);
 352 }
 353
 354 static void hook_xreq_get_uid_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int result)
 355 {
 356         _hook_xreq_(xreq, "get_uid() -> %d", result);
 357 }
 358
 359 static void hook_xreq_get_client_info_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *result)
 360 {
 361         _hook_xreq_(xreq, "get_client_info() -> %s", json_object_to_json_string_ext(result, JSON_C_TO_STRING_NOSLASHESCAPE));
 362 }
 363
 364 static struct afb_hook_xreq_itf hook_xreq_default_itf = {
 365         .hook_xreq_begin = hook_xreq_begin_cb,
 366         .hook_xreq_end = hook_xreq_end_cb,
 367         .hook_xreq_json = hook_xreq_json_cb,
 368         .hook_xreq_get = hook_xreq_get_cb,
 369         .hook_xreq_reply = hook_xreq_reply_cb,
 370         .hook_xreq_legacy_context_get = hook_xreq_legacy_context_get_cb,
 371         .hook_xreq_legacy_context_set = hook_xreq_legacy_context_set_cb,
 372         .hook_xreq_addref = hook_xreq_addref_cb,
 373         .hook_xreq_unref = hook_xreq_unref_cb,
 374         .hook_xreq_session_close = hook_xreq_session_close_cb,
 375         .hook_xreq_session_set_LOA = hook_xreq_session_set_LOA_cb,
 376         .hook_xreq_subscribe = hook_xreq_subscribe_cb,
 377         .hook_xreq_unsubscribe = hook_xreq_unsubscribe_cb,
 378         .hook_xreq_subcall = hook_xreq_subcall_cb,
 379         .hook_xreq_subcall_result = hook_xreq_subcall_result_cb,
 380         .hook_xreq_subcallsync = hook_xreq_subcallsync_cb,
 381         .hook_xreq_subcallsync_result = hook_xreq_subcallsync_result_cb,
 382         .hook_xreq_vverbose = hook_xreq_vverbose_cb,
 383         .hook_xreq_legacy_store = hook_xreq_legacy_store_cb,
 384         .hook_xreq_legacy_unstore = hook_xreq_legacy_unstore_cb,
 385         .hook_xreq_has_permission = hook_xreq_has_permission_cb,
 386         .hook_xreq_get_application_id = hook_xreq_get_application_id_cb,
 387         .hook_xreq_context_make = hook_xreq_context_make_cb,
 388         .hook_xreq_get_uid = hook_xreq_get_uid_cb,
 389         .hook_xreq_get_client_info = hook_xreq_get_client_info_cb,
 390 };
 391
 392 /******************************************************************************
 393  * section: hooks for tracing requests
 394  *****************************************************************************/
 395
 396 #define _HOOK_XREQ_2_(flag,func,...)   \
 397         struct afb_hook_xreq *hook; \
 398         struct afb_hookid hookid; \
 399         pthread_rwlock_rdlock(&rwlock); \
 400         init_hookid(&hookid); \
 401         hook = list_of_xreq_hooks; \
 402         while (hook) { \
 403                 if (hook->refcount \
 404                  && hook->itf->hook_xreq_##func \
 405                  && (hook->flags & afb_hook_flag_req_##flag) != 0 \
 406                  && (!hook->session || hook->session == xreq->context.session) \
 407                  && MATCH_API(hook->api, xreq->request.called_api) \
 408                  && MATCH_VERB(hook->verb, xreq->request.called_verb)) { \
 409                         hook->itf->hook_xreq_##func(hook->closure, &hookid, __VA_ARGS__); \
 410                 } \
 411                 hook = hook->next; \
 412         } \
 413         pthread_rwlock_unlock(&rwlock);
 414
 415 #define _HOOK_XREQ_(what,...)   _HOOK_XREQ_2_(what,what,__VA_ARGS__)
 416
 417 void afb_hook_xreq_begin(const struct afb_xreq *xreq)
 418 {
 419         _HOOK_XREQ_(begin, xreq);
 420 }
 421
 422 void afb_hook_xreq_end(const struct afb_xreq *xreq)
 423 {
 424         _HOOK_XREQ_(end, xreq);
 425 }
 426
 427 struct json_object *afb_hook_xreq_json(const struct afb_xreq *xreq, struct json_object *obj)
 428 {
 429         _HOOK_XREQ_(json, xreq, obj);
 430         return obj;
 431 }
 432
 433 struct afb_arg afb_hook_xreq_get(const struct afb_xreq *xreq, const char *name, struct afb_arg arg)
 434 {
 435         _HOOK_XREQ_(get, xreq, name, arg);
 436         return arg;
 437 }
 438
 439 void afb_hook_xreq_reply(const struct afb_xreq *xreq, struct json_object *obj, const char *error, const char *info)
 440 {
 441         _HOOK_XREQ_(reply, xreq, obj, error, info);
 442 }
 443
 444 void *afb_hook_xreq_legacy_context_get(const struct afb_xreq *xreq, void *value)
 445 {
 446         _HOOK_XREQ_(legacy_context_get, xreq, value);
 447         return value;
 448 }
 449
 450 void afb_hook_xreq_legacy_context_set(const struct afb_xreq *xreq, void *value, void (*free_value)(void*))
 451 {
 452         _HOOK_XREQ_(legacy_context_set, xreq, value, free_value);
 453 }
 454
 455 void afb_hook_xreq_addref(const struct afb_xreq *xreq)
 456 {
 457         _HOOK_XREQ_(addref, xreq);
 458 }
 459
 460 void afb_hook_xreq_unref(const struct afb_xreq *xreq)
 461 {
 462         _HOOK_XREQ_(unref, xreq);
 463 }
 464
 465 void afb_hook_xreq_session_close(const struct afb_xreq *xreq)
 466 {
 467         _HOOK_XREQ_(session_close, xreq);
 468 }
 469
 470 int afb_hook_xreq_session_set_LOA(const struct afb_xreq *xreq, unsigned level, int result)
 471 {
 472         _HOOK_XREQ_(session_set_LOA, xreq, level, result);
 473         return result;
 474 }
 475
 476 int afb_hook_xreq_subscribe(const struct afb_xreq *xreq, struct afb_event_x2 *event_x2, int result)
 477 {
 478         _HOOK_XREQ_(subscribe, xreq, event_x2, result);
 479         return result;
 480 }
 481
 482 int afb_hook_xreq_unsubscribe(const struct afb_xreq *xreq, struct afb_event_x2 *event_x2, int result)
 483 {
 484         _HOOK_XREQ_(unsubscribe, xreq, event_x2, result);
 485         return result;
 486 }
 487
 488 void afb_hook_xreq_subcall(const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args, int flags)
 489 {
 490         _HOOK_XREQ_(subcall, xreq, api, verb, args);
 491 }
 492
 493 void afb_hook_xreq_subcall_result(const struct afb_xreq *xreq, struct json_object *object, const char *error, const char *info)
 494 {
 495         _HOOK_XREQ_(subcall_result, xreq, object, error, info);
 496 }
 497
 498 void afb_hook_xreq_subcallsync(const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args, int flags)
 499 {
 500         _HOOK_XREQ_(subcallsync, xreq, api, verb, args);
 501 }
 502
 503 int  afb_hook_xreq_subcallsync_result(const struct afb_xreq *xreq, int status, struct json_object *object, const char *error, const char *info)
 504 {
 505         _HOOK_XREQ_(subcallsync_result, xreq, status, object, error, info);
 506         return status;
 507 }
 508
 509 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)
 510 {
 511         _HOOK_XREQ_(vverbose, xreq, level, file ?: "?", line, func ?: "?", fmt, args);
 512 }
 513
 514 void afb_hook_xreq_legacy_store(const struct afb_xreq *xreq, struct afb_stored_req *sreq)
 515 {
 516         _HOOK_XREQ_(legacy_store, xreq, sreq);
 517 }
 518
 519 void afb_hook_xreq_legacy_unstore(const struct afb_xreq *xreq)
 520 {
 521         _HOOK_XREQ_(legacy_unstore, xreq);
 522 }
 523
 524 int afb_hook_xreq_has_permission(const struct afb_xreq *xreq, const char *permission, int result)
 525 {
 526         _HOOK_XREQ_(has_permission, xreq, permission, result);
 527         return result;
 528 }
 529
 530 char *afb_hook_xreq_get_application_id(const struct afb_xreq *xreq, char *result)
 531 {
 532         _HOOK_XREQ_(get_application_id, xreq, result);
 533         return result;
 534 }
 535
 536 void *afb_hook_xreq_context_make(const struct afb_xreq *xreq, int replace, void *(*create_value)(void*), void (*free_value)(void*), void *create_closure, void *result)
 537 {
 538         _HOOK_XREQ_(context_make, xreq, replace, create_value, free_value, create_closure, result);
 539         return result;
 540 }
 541
 542 int afb_hook_xreq_get_uid(const struct afb_xreq *xreq, int result)
 543 {
 544         _HOOK_XREQ_(get_uid, xreq, result);
 545         return result;
 546 }
 547
 548 struct json_object *afb_hook_xreq_get_client_info(const struct afb_xreq *xreq, struct json_object *result)
 549 {
 550         _HOOK_XREQ_(get_client_info, xreq, result);
 551         return result;
 552 }
 553
 554 /******************************************************************************
 555  * section: hooking xreqs
 556  *****************************************************************************/
 557
 558 void afb_hook_init_xreq(struct afb_xreq *xreq)
 559 {
 560         static int reqindex = 0;
 561
 562         int f, flags;
 563         int add, x;
 564         struct afb_hook_xreq *hook;
 565
 566         /* scan hook list to get the expected flags */
 567         flags = 0;
 568         pthread_rwlock_rdlock(&rwlock);
 569         hook = list_of_xreq_hooks;
 570         while (hook) {
 571                 f = hook->flags & afb_hook_flags_req_all;
 572                 add = f != 0
 573                    && (!hook->session || hook->session == xreq->context.session)
 574                    && MATCH_API(hook->api, xreq->request.called_api)
 575                    && MATCH_VERB(hook->verb, xreq->request.called_verb);
 576                 if (add)
 577                         flags |= f;
 578                 hook = hook->next;
 579         }
 580         pthread_rwlock_unlock(&rwlock);
 581
 582         /* store the hooking data */
 583         xreq->hookflags = flags;
 584         if (flags) {
 585                 do {
 586                         x = __atomic_load_n(&reqindex, __ATOMIC_RELAXED);
 587                         xreq->hookindex = (x + 1) % 1000000 ?: 1;
 588                 } while (x != __atomic_exchange_n(&reqindex, xreq->hookindex, __ATOMIC_RELAXED));
 589         }
 590 }
 591
 592 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)
 593 {
 594         struct afb_hook_xreq *hook;
 595
 596         /* alloc the result */
 597         hook = calloc(1, sizeof *hook);
 598         if (hook == NULL)
 599                 return NULL;
 600
 601         /* get a copy of the names */
 602         hook->api = api ? strdup(api) : NULL;
 603         hook->verb = verb ? strdup(verb) : NULL;
 604         if ((api && !hook->api) || (verb && !hook->verb)) {
 605                 free(hook->api);
 606                 free(hook->verb);
 607                 free(hook);
 608                 return NULL;
 609         }
 610
 611         /* initialise the rest */
 612         hook->session = session;
 613         if (session)
 614                 afb_session_addref(session);
 615         hook->refcount = 1;
 616         hook->flags = flags;
 617         hook->itf = itf ? itf : &hook_xreq_default_itf;
 618         hook->closure = closure;
 619
 620         /* record the hook */
 621         pthread_mutex_lock(&mutex);
 622         hook->next = list_of_xreq_hooks;
 623         list_of_xreq_hooks = hook;
 624         pthread_mutex_unlock(&mutex);
 625
 626         /* returns it */
 627         return hook;
 628 }
 629
 630 struct afb_hook_xreq *afb_hook_addref_xreq(struct afb_hook_xreq *hook)
 631 {
 632         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
 633         return hook;
 634 }
 635
 636 static void hook_clean_xreq()
 637 {
 638         struct afb_hook_xreq **prv, *hook, *head;
 639
 640         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
 641                 /* unlink under mutex */
 642                 head = NULL;
 643                 pthread_mutex_lock(&mutex);
 644                 prv = &list_of_xreq_hooks;
 645                 while ((hook = *prv)) {
 646                         if (hook->refcount)
 647                                 prv = &(*prv)->next;
 648                         else {
 649                                 *prv = hook->next;
 650                                 hook->next = head;
 651                                 head = hook;
 652                         }
 653                 }
 654                 pthread_mutex_unlock(&mutex);
 655                 pthread_rwlock_unlock(&rwlock);
 656
 657                 /* free found hooks */
 658                 while((hook = head)) {
 659                         head = hook->next;
 660                         free(hook->api);
 661                         free(hook->verb);
 662                         if (hook->session)
 663                                 afb_session_unref(hook->session);
 664                         free(hook);
 665                 }
 666         }
 667 }
 668
 669 void afb_hook_unref_xreq(struct afb_hook_xreq *hook)
 670 {
 671         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
 672                 hook_clean_xreq();
 673 }
 674
 675 /******************************************************************************
 676  * section: default callbacks for tracing daemon interface
 677  *****************************************************************************/
 678
 679 static void _hook_api_(const struct afb_export *export, const char *format, ...)
 680 {
 681         va_list ap;
 682         va_start(ap, format);
 683         _hook_("api-%s", format, ap, afb_export_apiname(export));
 684         va_end(ap);
 685 }
 686
 687 static void hook_api_event_broadcast_before_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *name, struct json_object *object)
 688 {
 689         _hook_api_(export, "event_broadcast.before(%s, %s)....", name, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 690 }
 691
 692 static void hook_api_event_broadcast_after_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *name, struct json_object *object, int result)
 693 {
 694         _hook_api_(export, "event_broadcast.after(%s, %s) -> %d", name, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), result);
 695 }
 696
 697 static void hook_api_get_event_loop_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct sd_event *result)
 698 {
 699         _hook_api_(export, "get_event_loop() -> %p", result);
 700 }
 701
 702 static void hook_api_get_user_bus_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct sd_bus *result)
 703 {
 704         _hook_api_(export, "get_user_bus() -> %p", result);
 705 }
 706
 707 static void hook_api_get_system_bus_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct sd_bus *result)
 708 {
 709         _hook_api_(export, "get_system_bus() -> %p", result);
 710 }
 711
 712 static void hook_api_vverbose_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int level, const char *file, int line, const char *function, const char *fmt, va_list args)
 713 {
 714         int len;
 715         char *msg;
 716         va_list ap;
 717
 718         va_copy(ap, args);
 719         len = vasprintf(&msg, fmt, ap);
 720         va_end(ap);
 721
 722         if (len < 0)
 723                 _hook_api_(export, "vverbose(%d:%s, %s, %d, %s) -> %s ? ? ?", level, verbose_name_of_level(level), file, line, function, fmt);
 724         else {
 725                 _hook_api_(export, "vverbose(%d:%s, %s, %d, %s) -> %s", level, verbose_name_of_level(level), file, line, function, msg);
 726                 free(msg);
 727         }
 728 }
 729
 730 static void hook_api_event_make_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *name, struct afb_event_x2 *result)
 731 {
 732         _hook_api_(export, "event_make(%s) -> %s:%d", name, afb_evt_event_x2_fullname(result), afb_evt_event_x2_id(result));
 733 }
 734
 735 static void hook_api_rootdir_get_fd_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 736 {
 737         char path[PATH_MAX], proc[100];
 738         ssize_t s;
 739
 740         if (result < 0)
 741                 _hook_api_(export, "rootdir_get_fd() -> %d, %m", result);
 742         else {
 743                 snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
 744                 s = readlink(proc, path, sizeof path);
 745                 path[s < 0 ? 0 : s >= sizeof path ? sizeof path - 1 : s] = 0;
 746                 _hook_api_(export, "rootdir_get_fd() -> %d = %s", result, path);
 747         }
 748 }
 749
 750 static void hook_api_rootdir_open_locale_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *filename, int flags, const char *locale, int result)
 751 {
 752         char path[PATH_MAX], proc[100];
 753         ssize_t s;
 754
 755         if (!locale)
 756                 locale = "(null)";
 757         if (result < 0)
 758                 _hook_api_(export, "rootdir_open_locale(%s, %d, %s) -> %d, %m", filename, flags, locale, result);
 759         else {
 760                 snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
 761                 s = readlink(proc, path, sizeof path);
 762                 path[s < 0 ? 0 : s >= sizeof path ? sizeof path - 1 : s] = 0;
 763                 _hook_api_(export, "rootdir_open_locale(%s, %d, %s) -> %d = %s", filename, flags, locale, result, path);
 764         }
 765 }
 766
 767 static void hook_api_queue_job_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, void (*callback)(int signum, void *arg), void *argument, void *group, int timeout, int result)
 768 {
 769         _hook_api_(export, "queue_job(%p, %p, %p, %d) -> %d", callback, argument, group, timeout, result);
 770 }
 771
 772 static void hook_api_unstore_req_cb(void *closure, const struct afb_hookid *hookid,  const struct afb_export *export, struct afb_stored_req *sreq)
 773 {
 774         _hook_api_(export, "unstore_req(%p)", sreq);
 775 }
 776
 777 static void hook_api_require_api_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *name, int initialized)
 778 {
 779         _hook_api_(export, "require_api(%s, %d)...", name, initialized);
 780 }
 781
 782 static void hook_api_require_api_result_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *name, int initialized, int result)
 783 {
 784         _hook_api_(export, "...require_api(%s, %d) -> %d", name, initialized, result);
 785 }
 786
 787 static void hook_api_add_alias_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *api, const char *alias, int result)
 788 {
 789         _hook_api_(export, "add_alias(%s -> %s) -> %d", api, alias?:"<null>", result);
 790 }
 791
 792 static void hook_api_start_before_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export)
 793 {
 794         _hook_api_(export, "start.before");
 795 }
 796
 797 static void hook_api_start_after_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int status)
 798 {
 799         _hook_api_(export, "start.after -> %d", status);
 800 }
 801
 802 static void hook_api_on_event_before_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *event, int event_x2, struct json_object *object)
 803 {
 804         _hook_api_(export, "on_event.before(%s, %d, %s)", event, event_x2, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 805 }
 806
 807 static void hook_api_on_event_after_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *event, int event_x2, struct json_object *object)
 808 {
 809         _hook_api_(export, "on_event.after(%s, %d, %s)", event, event_x2, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 810 }
 811
 812 static void hook_api_call_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *api, const char *verb, struct json_object *args)
 813 {
 814         _hook_api_(export, "call(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 815 }
 816
 817 static void hook_api_call_result_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct json_object *object, const char *error, const char *info)
 818 {
 819         _hook_api_(export, "    ...call... [%s] -> %s (%s)", error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 820 }
 821
 822 static void hook_api_callsync_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *api, const char *verb, struct json_object *args)
 823 {
 824         _hook_api_(export, "callsync(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 825 }
 826
 827 static void hook_api_callsync_result_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int status, struct json_object *object, const char *error, const char *info)
 828 {
 829         _hook_api_(export, "    ...callsync... %d [%s] -> %s (%s)", status, error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 830 }
 831
 832 static void hook_api_new_api_before_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *api, const char *info, int noconcurrency)
 833 {
 834         _hook_api_(export, "new_api.before %s (%s)%s ...", api, info?:"", noconcurrency?" no-concurrency" : "");
 835 }
 836
 837 static void hook_api_new_api_after_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *api)
 838 {
 839         _hook_api_(export, "... new_api.after %s -> %s (%d)", api, result >= 0 ? "OK" : "ERROR", result);
 840 }
 841
 842 static void hook_api_api_set_verbs_v2_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const struct afb_verb_v2 *verbs)
 843 {
 844         _hook_api_(export, "set_verbs_v2 -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 845 }
 846
 847 static void hook_api_api_set_verbs_v3_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const struct afb_verb_v3 *verbs)
 848 {
 849         _hook_api_(export, "set_verbs_v3 -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 850 }
 851
 852 static void hook_api_api_add_verb_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *verb, const char *info, int glob)
 853 {
 854         _hook_api_(export, "add_verb(%s%s [%s]) -> %s (%d)", verb, glob?" (GLOB)":"", info?:"", result >= 0 ? "OK" : "ERROR", result);
 855 }
 856
 857 static void hook_api_api_del_verb_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *verb)
 858 {
 859         _hook_api_(export, "del_verb(%s) -> %s (%d)", verb, result >= 0 ? "OK" : "ERROR", result);
 860 }
 861
 862 static void hook_api_api_set_on_event_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 863 {
 864         _hook_api_(export, "set_on_event -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 865 }
 866
 867 static void hook_api_api_set_on_init_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 868 {
 869         _hook_api_(export, "set_on_init -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 870 }
 871
 872 static void hook_api_api_seal_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export)
 873 {
 874         _hook_api_(export, "seal");
 875 }
 876
 877 static void hook_api_event_handler_add_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *pattern)
 878 {
 879         _hook_api_(export, "event_handler_add(%s) -> %s (%d)", pattern, result >= 0 ? "OK" : "ERROR", result);
 880 }
 881
 882 static void hook_api_event_handler_del_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *pattern)
 883 {
 884         _hook_api_(export, "event_handler_del(%s) -> %s (%d)", pattern, result >= 0 ? "OK" : "ERROR", result);
 885 }
 886
 887 static void hook_api_class_provide_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *name)
 888 {
 889         _hook_api_(export, "class_provide(%s) -> %s (%d)", name, result >= 0 ? "OK" : "ERROR", result);
 890 }
 891
 892 static void hook_api_class_require_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *name)
 893 {
 894         _hook_api_(export, "class_require(%s) -> %s (%d)", name, result >= 0 ? "OK" : "ERROR", result);
 895 }
 896
 897 static void hook_api_delete_api_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 898 {
 899         _hook_api_(export, "delete_api -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 900 }
 901
 902 static void hook_api_on_event_handler_before_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *event, int event_x2, struct json_object *object, const char *pattern)
 903 {
 904         _hook_api_(export, "on_event_handler[%s].before(%s, %d, %s)", pattern, event, event_x2, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 905 }
 906
 907 static void hook_api_on_event_handler_after_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *event, int event_x2, struct json_object *object, const char *pattern)
 908 {
 909         _hook_api_(export, "on_event_handler[%s].after(%s, %d, %s)", pattern, event, event_x2, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 910 }
 911
 912 static void hook_api_settings_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct json_object *object)
 913 {
 914         _hook_api_(export, "settings -> %s", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 915 }
 916
 917 static struct afb_hook_api_itf hook_api_default_itf = {
 918         .hook_api_event_broadcast_before = hook_api_event_broadcast_before_cb,
 919         .hook_api_event_broadcast_after = hook_api_event_broadcast_after_cb,
 920         .hook_api_get_event_loop = hook_api_get_event_loop_cb,
 921         .hook_api_get_user_bus = hook_api_get_user_bus_cb,
 922         .hook_api_get_system_bus = hook_api_get_system_bus_cb,
 923         .hook_api_vverbose = hook_api_vverbose_cb,
 924         .hook_api_event_make = hook_api_event_make_cb,
 925         .hook_api_rootdir_get_fd = hook_api_rootdir_get_fd_cb,
 926         .hook_api_rootdir_open_locale = hook_api_rootdir_open_locale_cb,
 927         .hook_api_queue_job = hook_api_queue_job_cb,
 928         .hook_api_legacy_unstore_req = hook_api_unstore_req_cb,
 929         .hook_api_require_api = hook_api_require_api_cb,
 930         .hook_api_require_api_result = hook_api_require_api_result_cb,
 931         .hook_api_add_alias = hook_api_add_alias_cb,
 932         .hook_api_start_before = hook_api_start_before_cb,
 933         .hook_api_start_after = hook_api_start_after_cb,
 934         .hook_api_on_event_before = hook_api_on_event_before_cb,
 935         .hook_api_on_event_after = hook_api_on_event_after_cb,
 936         .hook_api_call = hook_api_call_cb,
 937         .hook_api_call_result = hook_api_call_result_cb,
 938         .hook_api_callsync = hook_api_callsync_cb,
 939         .hook_api_callsync_result = hook_api_callsync_result_cb,
 940         .hook_api_new_api_before = hook_api_new_api_before_cb,
 941         .hook_api_new_api_after = hook_api_new_api_after_cb,
 942         .hook_api_api_set_verbs_v2 = hook_api_api_set_verbs_v2_cb,
 943         .hook_api_api_set_verbs_v3 = hook_api_api_set_verbs_v3_cb,
 944         .hook_api_api_add_verb = hook_api_api_add_verb_cb,
 945         .hook_api_api_del_verb = hook_api_api_del_verb_cb,
 946         .hook_api_api_set_on_event = hook_api_api_set_on_event_cb,
 947         .hook_api_api_set_on_init = hook_api_api_set_on_init_cb,
 948         .hook_api_api_seal = hook_api_api_seal_cb,
 949         .hook_api_event_handler_add = hook_api_event_handler_add_cb,
 950         .hook_api_event_handler_del = hook_api_event_handler_del_cb,
 951         .hook_api_class_provide = hook_api_class_provide_cb,
 952         .hook_api_class_require = hook_api_class_require_cb,
 953         .hook_api_delete_api = hook_api_delete_api_cb,
 954         .hook_api_on_event_handler_before = hook_api_on_event_handler_before_cb,
 955         .hook_api_on_event_handler_after = hook_api_on_event_handler_after_cb,
 956         .hook_api_settings = hook_api_settings_cb,
 957 };
 958
 959 /******************************************************************************
 960  * section: hooks for tracing daemon interface (export)
 961  *****************************************************************************/
 962
 963 #define _HOOK_API_2_(flag,func,...)   \
 964         struct afb_hook_api *hook; \
 965         struct afb_hookid hookid; \
 966         const char *apiname = afb_export_apiname(export); \
 967         pthread_rwlock_rdlock(&rwlock); \
 968         init_hookid(&hookid); \
 969         hook = list_of_api_hooks; \
 970         while (hook) { \
 971                 if (hook->refcount \
 972                  && hook->itf->hook_api_##func \
 973                  && (hook->flags & afb_hook_flag_api_##flag) != 0 \
 974                  && MATCH_API(hook->api, apiname)) { \
 975                         hook->itf->hook_api_##func(hook->closure, &hookid, __VA_ARGS__); \
 976                 } \
 977                 hook = hook->next; \
 978         } \
 979         pthread_rwlock_unlock(&rwlock);
 980
 981 #define _HOOK_API_(what,...)   _HOOK_API_2_(what,what,__VA_ARGS__)
 982
 983 void afb_hook_api_event_broadcast_before(const struct afb_export *export, const char *name, struct json_object *object)
 984 {
 985         _HOOK_API_2_(event_broadcast, event_broadcast_before, export, name, object);
 986 }
 987
 988 int afb_hook_api_event_broadcast_after(const struct afb_export *export, const char *name, struct json_object *object, int result)
 989 {
 990         _HOOK_API_2_(event_broadcast, event_broadcast_after, export, name, object, result);
 991         return result;
 992 }
 993
 994 struct sd_event *afb_hook_api_get_event_loop(const struct afb_export *export, struct sd_event *result)
 995 {
 996         _HOOK_API_(get_event_loop, export, result);
 997         return result;
 998 }
 999
1000 struct sd_bus *afb_hook_api_get_user_bus(const struct afb_export *export, struct sd_bus *result)
1001 {
1002         _HOOK_API_(get_user_bus, export, result);
1003         return result;
1004 }
1005
1006 struct sd_bus *afb_hook_api_get_system_bus(const struct afb_export *export, struct sd_bus *result)
1007 {
1008         _HOOK_API_(get_system_bus, export, result);
1009         return result;
1010 }
1011
1012 void afb_hook_api_vverbose(const struct afb_export *export, int level, const char *file, int line, const char *function, const char *fmt, va_list args)
1013 {
1014         _HOOK_API_(vverbose, export, level, file, line, function, fmt, args);
1015 }
1016
1017 struct afb_event_x2 *afb_hook_api_event_make(const struct afb_export *export, const char *name, struct afb_event_x2 *result)
1018 {
1019         _HOOK_API_(event_make, export, name, result);
1020         return result;
1021 }
1022
1023 int afb_hook_api_rootdir_get_fd(const struct afb_export *export, int result)
1024 {
1025         _HOOK_API_(rootdir_get_fd, export, result);
1026         return result;
1027 }
1028
1029 int afb_hook_api_rootdir_open_locale(const struct afb_export *export, const char *filename, int flags, const char *locale, int result)
1030 {
1031         _HOOK_API_(rootdir_open_locale, export, filename, flags, locale, result);
1032         return result;
1033 }
1034
1035 int afb_hook_api_queue_job(const struct afb_export *export, void (*callback)(int signum, void *arg), void *argument, void *group, int timeout, int result)
1036 {
1037         _HOOK_API_(queue_job, export, callback, argument, group, timeout, result);
1038         return result;
1039 }
1040
1041 void afb_hook_api_legacy_unstore_req(const struct afb_export *export, struct afb_stored_req *sreq)
1042 {
1043         _HOOK_API_(legacy_unstore_req, export, sreq);
1044 }
1045
1046 void afb_hook_api_require_api(const struct afb_export *export, const char *name, int initialized)
1047 {
1048         _HOOK_API_(require_api, export, name, initialized);
1049 }
1050
1051 int afb_hook_api_require_api_result(const struct afb_export *export, const char *name, int initialized, int result)
1052 {
1053         _HOOK_API_2_(require_api, require_api_result, export, name, initialized, result);
1054         return result;
1055 }
1056
1057 int afb_hook_api_add_alias(const struct afb_export *export, const char *api, const char *alias, int result)
1058 {
1059         _HOOK_API_(add_alias, export, api, alias, result);
1060         return result;
1061 }
1062
1063 void afb_hook_api_start_before(const struct afb_export *export)
1064 {
1065         _HOOK_API_2_(start, start_before, export);
1066 }
1067
1068 int afb_hook_api_start_after(const struct afb_export *export, int status)
1069 {
1070         _HOOK_API_2_(start, start_after, export, status);
1071         return status;
1072 }
1073
1074 void afb_hook_api_on_event_before(const struct afb_export *export, const char *event, int event_x2, struct json_object *object)
1075 {
1076         _HOOK_API_2_(on_event, on_event_before, export, event, event_x2, object);
1077 }
1078
1079 void afb_hook_api_on_event_after(const struct afb_export *export, const char *event, int event_x2, struct json_object *object)
1080 {
1081         _HOOK_API_2_(on_event, on_event_after, export, event, event_x2, object);
1082 }
1083
1084 void afb_hook_api_call(const struct afb_export *export, const char *api, const char *verb, struct json_object *args)
1085 {
1086         _HOOK_API_(call, export, api, verb, args);
1087 }
1088
1089 void afb_hook_api_call_result(const struct afb_export *export, struct json_object *object, const char*error, const char *info)
1090 {
1091         _HOOK_API_2_(call, call_result, export, object, error, info);
1092
1093 }
1094
1095 void afb_hook_api_callsync(const struct afb_export *export, const char *api, const char *verb, struct json_object *args)
1096 {
1097         _HOOK_API_(callsync, export, api, verb, args);
1098 }
1099
1100 int afb_hook_api_callsync_result(const struct afb_export *export, int status, struct json_object *object, const char *error, const char *info)
1101 {
1102         _HOOK_API_2_(callsync, callsync_result, export, status, object, error, info);
1103         return status;
1104 }
1105
1106 void afb_hook_api_new_api_before(const struct afb_export *export, const char *api, const char *info, int noconcurrency)
1107 {
1108         _HOOK_API_2_(new_api, new_api_before, export, api, info, noconcurrency);
1109 }
1110
1111 int afb_hook_api_new_api_after(const struct afb_export *export, int result, const char *api)
1112 {
1113         _HOOK_API_2_(new_api, new_api_after, export, result, api);
1114         return result;
1115 }
1116
1117 int afb_hook_api_api_set_verbs_v2(const struct afb_export *export, int result, const struct afb_verb_v2 *verbs)
1118 {
1119         _HOOK_API_2_(api_set_verbs, api_set_verbs_v2, export, result, verbs);
1120         return result;
1121 }
1122
1123 int afb_hook_api_api_set_verbs_v3(const struct afb_export *export, int result, const struct afb_verb_v3 *verbs)
1124 {
1125         _HOOK_API_2_(api_set_verbs, api_set_verbs_v3, export, result, verbs);
1126         return result;
1127 }
1128
1129 int afb_hook_api_api_add_verb(const struct afb_export *export, int result, const char *verb, const char *info, int glob)
1130 {
1131         _HOOK_API_(api_add_verb, export, result, verb, info, glob);
1132         return result;
1133 }
1134
1135 int afb_hook_api_api_del_verb(const struct afb_export *export, int result, const char *verb)
1136 {
1137         _HOOK_API_(api_del_verb, export, result, verb);
1138         return result;
1139 }
1140
1141 int afb_hook_api_api_set_on_event(const struct afb_export *export, int result)
1142 {
1143         _HOOK_API_(api_set_on_event, export, result);
1144         return result;
1145 }
1146
1147 int afb_hook_api_api_set_on_init(const struct afb_export *export, int result)
1148 {
1149         _HOOK_API_(api_set_on_init, export, result);
1150         return result;
1151 }
1152
1153 void afb_hook_api_api_seal(const struct afb_export *export)
1154 {
1155         _HOOK_API_(api_seal, export);
1156 }
1157
1158 int afb_hook_api_event_handler_add(const struct afb_export *export, int result, const char *pattern)
1159 {
1160         _HOOK_API_(event_handler_add, export, result, pattern);
1161         return result;
1162 }
1163 int afb_hook_api_event_handler_del(const struct afb_export *export, int result, const char *pattern)
1164 {
1165         _HOOK_API_(event_handler_del, export, result, pattern);
1166         return result;
1167 }
1168 int afb_hook_api_class_provide(const struct afb_export *export, int result, const char *name)
1169 {
1170         _HOOK_API_(class_provide, export, result, name);
1171         return result;
1172 }
1173 int afb_hook_api_class_require(const struct afb_export *export, int result, const char *name)
1174 {
1175         _HOOK_API_(class_require, export, result, name);
1176         return result;
1177 }
1178
1179 int afb_hook_api_delete_api(const struct afb_export *export, int result)
1180 {
1181         _HOOK_API_(delete_api, export, result);
1182         return result;
1183 }
1184
1185 void afb_hook_api_on_event_handler_before(const struct afb_export *export, const char *event, int event_x2, struct json_object *object, const char *pattern)
1186 {
1187         _HOOK_API_2_(on_event_handler, on_event_handler_before, export, event, event_x2, object, pattern);
1188 }
1189
1190 void afb_hook_api_on_event_handler_after(const struct afb_export *export, const char *event, int event_x2, struct json_object *object, const char *pattern)
1191 {
1192         _HOOK_API_2_(on_event_handler, on_event_handler_after, export, event, event_x2, object, pattern);
1193 }
1194
1195 struct json_object *afb_hook_api_settings(const struct afb_export *export, struct json_object *object)
1196 {
1197         _HOOK_API_(settings, export, object);
1198         return object;
1199 }
1200
1201 /******************************************************************************
1202  * section: hooking export
1203  *****************************************************************************/
1204
1205 int afb_hook_flags_api(const char *api)
1206 {
1207         int flags;
1208         struct afb_hook_api *hook;
1209
1210         flags = 0;
1211         pthread_rwlock_rdlock(&rwlock);
1212         hook = list_of_api_hooks;
1213         while (hook) {
1214                 if (!api || MATCH_API(hook->api, api))
1215                         flags |= hook->flags;
1216                 hook = hook->next;
1217         }
1218         pthread_rwlock_unlock(&rwlock);
1219         return flags;
1220 }
1221
1222 struct afb_hook_api *afb_hook_create_api(const char *api, int flags, struct afb_hook_api_itf *itf, void *closure)
1223 {
1224         struct afb_hook_api *hook;
1225
1226         /* alloc the result */
1227         hook = calloc(1, sizeof *hook);
1228         if (hook == NULL)
1229                 return NULL;
1230
1231         /* get a copy of the names */
1232         hook->api = api ? strdup(api) : NULL;
1233         if (api && !hook->api) {
1234                 free(hook);
1235                 return NULL;
1236         }
1237
1238         /* initialise the rest */
1239         hook->refcount = 1;
1240         hook->flags = flags;
1241         hook->itf = itf ? itf : &hook_api_default_itf;
1242         hook->closure = closure;
1243
1244         /* record the hook */
1245         pthread_mutex_lock(&mutex);
1246         hook->next = list_of_api_hooks;
1247         list_of_api_hooks = hook;
1248         pthread_mutex_unlock(&mutex);
1249
1250         /* returns it */
1251         return hook;
1252 }
1253
1254 struct afb_hook_api *afb_hook_addref_api(struct afb_hook_api *hook)
1255 {
1256         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1257         return hook;
1258 }
1259
1260 static void hook_clean_api()
1261 {
1262         struct afb_hook_api **prv, *hook, *head;
1263
1264         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1265                 /* unlink under mutex */
1266                 head = NULL;
1267                 pthread_mutex_lock(&mutex);
1268                 prv = &list_of_api_hooks;
1269                 while ((hook = *prv)) {
1270                         if (hook->refcount)
1271                                 prv = &(*prv)->next;
1272                         else {
1273                                 *prv = hook->next;
1274                                 hook->next = head;
1275                                 head = hook;
1276                         }
1277                 }
1278                 pthread_mutex_unlock(&mutex);
1279                 pthread_rwlock_unlock(&rwlock);
1280
1281                 /* free found hooks */
1282                 while((hook = head)) {
1283                         head = hook->next;
1284                         free(hook->api);
1285                         free(hook);
1286                 }
1287         }
1288 }
1289
1290 void afb_hook_unref_api(struct afb_hook_api *hook)
1291 {
1292         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
1293                 hook_clean_api();
1294 }
1295
1296 /******************************************************************************
1297  * section: default callbacks for tracing service interface (evt)
1298  *****************************************************************************/
1299
1300 static void _hook_evt_(const char *evt, int id, const char *format, ...)
1301 {
1302         va_list ap;
1303         va_start(ap, format);
1304         _hook_("evt-%s:%d", format, ap, evt, id);
1305         va_end(ap);
1306 }
1307
1308 static void hook_evt_create_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1309 {
1310         _hook_evt_(evt, id, "create");
1311 }
1312
1313 static void hook_evt_push_before_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj)
1314 {
1315         _hook_evt_(evt, id, "push.before(%s)", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE));
1316 }
1317
1318
1319 static void hook_evt_push_after_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj, int result)
1320 {
1321         _hook_evt_(evt, id, "push.after(%s) -> %d", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE), result);
1322 }
1323
1324 static void hook_evt_broadcast_before_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj)
1325 {
1326         _hook_evt_(evt, id, "broadcast.before(%s)", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE));
1327 }
1328
1329 static void hook_evt_broadcast_after_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj, int result)
1330 {
1331         _hook_evt_(evt, id, "broadcast.after(%s) -> %d", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE), result);
1332 }
1333
1334 static void hook_evt_name_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, const char *result)
1335 {
1336         _hook_evt_(evt, id, "name -> %s", result);
1337 }
1338
1339 static void hook_evt_addref_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1340 {
1341         _hook_evt_(evt, id, "addref");
1342 }
1343
1344 static void hook_evt_unref_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1345 {
1346         _hook_evt_(evt, id, "unref");
1347 }
1348
1349 static struct afb_hook_evt_itf hook_evt_default_itf = {
1350         .hook_evt_create = hook_evt_create_cb,
1351         .hook_evt_push_before = hook_evt_push_before_cb,
1352         .hook_evt_push_after = hook_evt_push_after_cb,
1353         .hook_evt_broadcast_before = hook_evt_broadcast_before_cb,
1354         .hook_evt_broadcast_after = hook_evt_broadcast_after_cb,
1355         .hook_evt_name = hook_evt_name_cb,
1356         .hook_evt_addref = hook_evt_addref_cb,
1357         .hook_evt_unref = hook_evt_unref_cb
1358 };
1359
1360 /******************************************************************************
1361  * section: hooks for tracing events interface (evt)
1362  *****************************************************************************/
1363
1364 #define _HOOK_EVT_(what,...)   \
1365         struct afb_hook_evt *hook; \
1366         struct afb_hookid hookid; \
1367         pthread_rwlock_rdlock(&rwlock); \
1368         init_hookid(&hookid); \
1369         hook = list_of_evt_hooks; \
1370         while (hook) { \
1371                 if (hook->refcount \
1372                  && hook->itf->hook_evt_##what \
1373                  && (hook->flags & afb_hook_flag_evt_##what) != 0 \
1374                  && MATCH_EVENT(hook->pattern, evt)) { \
1375                         hook->itf->hook_evt_##what(hook->closure, &hookid, __VA_ARGS__); \
1376                 } \
1377                 hook = hook->next; \
1378         } \
1379         pthread_rwlock_unlock(&rwlock);
1380
1381 void afb_hook_evt_create(const char *evt, int id)
1382 {
1383         _HOOK_EVT_(create, evt, id);
1384 }
1385
1386 void afb_hook_evt_push_before(const char *evt, int id, struct json_object *obj)
1387 {
1388         _HOOK_EVT_(push_before, evt, id, obj);
1389 }
1390
1391 int afb_hook_evt_push_after(const char *evt, int id, struct json_object *obj, int result)
1392 {
1393         _HOOK_EVT_(push_after, evt, id, obj, result);
1394         return result;
1395 }
1396
1397 void afb_hook_evt_broadcast_before(const char *evt, int id, struct json_object *obj)
1398 {
1399         _HOOK_EVT_(broadcast_before, evt, id, obj);
1400 }
1401
1402 int afb_hook_evt_broadcast_after(const char *evt, int id, struct json_object *obj, int result)
1403 {
1404         _HOOK_EVT_(broadcast_after, evt, id, obj, result);
1405         return result;
1406 }
1407
1408 void afb_hook_evt_name(const char *evt, int id, const char *result)
1409 {
1410         _HOOK_EVT_(name, evt, id, result);
1411 }
1412
1413 void afb_hook_evt_addref(const char *evt, int id)
1414 {
1415         _HOOK_EVT_(addref, evt, id);
1416 }
1417
1418 void afb_hook_evt_unref(const char *evt, int id)
1419 {
1420         _HOOK_EVT_(unref, evt, id);
1421 }
1422
1423 /******************************************************************************
1424  * section: hooking services (evt)
1425  *****************************************************************************/
1426
1427 int afb_hook_flags_evt(const char *name)
1428 {
1429         int flags;
1430         struct afb_hook_evt *hook;
1431
1432         flags = 0;
1433         pthread_rwlock_rdlock(&rwlock);
1434         hook = list_of_evt_hooks;
1435         while (hook) {
1436                 if (!name || MATCH_EVENT(hook->pattern, name))
1437                         flags |= hook->flags;
1438                 hook = hook->next;
1439         }
1440         pthread_rwlock_unlock(&rwlock);
1441         return flags;
1442 }
1443
1444 struct afb_hook_evt *afb_hook_create_evt(const char *pattern, int flags, struct afb_hook_evt_itf *itf, void *closure)
1445 {
1446         struct afb_hook_evt *hook;
1447
1448         /* alloc the result */
1449         hook = calloc(1, sizeof *hook);
1450         if (hook == NULL)
1451                 return NULL;
1452
1453         /* get a copy of the names */
1454         hook->pattern = pattern ? strdup(pattern) : NULL;
1455         if (pattern && !hook->pattern) {
1456                 free(hook);
1457                 return NULL;
1458         }
1459
1460         /* initialise the rest */
1461         hook->refcount = 1;
1462         hook->flags = flags;
1463         hook->itf = itf ? itf : &hook_evt_default_itf;
1464         hook->closure = closure;
1465
1466         /* record the hook */
1467         pthread_mutex_lock(&mutex);
1468         hook->next = list_of_evt_hooks;
1469         list_of_evt_hooks = hook;
1470         pthread_mutex_unlock(&mutex);
1471
1472         /* returns it */
1473         return hook;
1474 }
1475
1476 struct afb_hook_evt *afb_hook_addref_evt(struct afb_hook_evt *hook)
1477 {
1478         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1479         return hook;
1480 }
1481
1482 static void hook_clean_evt()
1483 {
1484         struct afb_hook_evt **prv, *hook, *head;
1485
1486         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1487                 /* unlink under mutex */
1488                 head = NULL;
1489                 pthread_mutex_lock(&mutex);
1490                 prv = &list_of_evt_hooks;
1491                 while ((hook = *prv)) {
1492                         if (hook->refcount)
1493                                 prv = &(*prv)->next;
1494                         else {
1495                                 *prv = hook->next;
1496                                 hook->next = head;
1497                                 head = hook;
1498                         }
1499                 }
1500                 pthread_mutex_unlock(&mutex);
1501                 pthread_rwlock_unlock(&rwlock);
1502
1503                 /* free found hooks */
1504                 while((hook = head)) {
1505                         head = hook->next;
1506                         free(hook->pattern);
1507                         free(hook);
1508                 }
1509         }
1510 }
1511
1512 void afb_hook_unref_evt(struct afb_hook_evt *hook)
1513 {
1514         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
1515                 hook_clean_evt();
1516 }
1517
1518 /******************************************************************************
1519  * section: default callbacks for sessions (session)
1520  *****************************************************************************/
1521
1522 static void _hook_session_(struct afb_session *session, const char *format, ...)
1523 {
1524         va_list ap;
1525         va_start(ap, format);
1526         _hook_("session-%s", format, ap, afb_session_uuid(session));
1527         va_end(ap);
1528 }
1529
1530 static void hook_session_create_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1531 {
1532         _hook_session_(session, "create -> token=%s", afb_session_token(session));
1533 }
1534
1535 static void hook_session_close_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1536 {
1537         _hook_session_(session, "close");
1538 }
1539
1540 static void hook_session_destroy_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1541 {
1542         _hook_session_(session, "destroy");
1543 }
1544
1545 static void hook_session_renew_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1546 {
1547         _hook_session_(session, "renew -> token=%s", afb_session_token(session));
1548 }
1549
1550 static void hook_session_addref_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1551 {
1552         _hook_session_(session, "addref");
1553 }
1554
1555 static void hook_session_unref_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1556 {
1557         _hook_session_(session, "unref");
1558 }
1559
1560 static struct afb_hook_session_itf hook_session_default_itf = {
1561         .hook_session_create = hook_session_create_cb,
1562         .hook_session_close = hook_session_close_cb,
1563         .hook_session_destroy = hook_session_destroy_cb,
1564         .hook_session_renew = hook_session_renew_cb,
1565         .hook_session_addref = hook_session_addref_cb,
1566         .hook_session_unref = hook_session_unref_cb
1567 };
1568
1569 /******************************************************************************
1570  * section: hooks for tracing sessions (session)
1571  *****************************************************************************/
1572
1573 #define _HOOK_SESSION_(what,...)   \
1574         struct afb_hook_session *hook; \
1575         struct afb_hookid hookid; \
1576         const char *sessid = 0; \
1577         pthread_rwlock_rdlock(&rwlock); \
1578         init_hookid(&hookid); \
1579         hook = list_of_session_hooks; \
1580         while (hook) { \
1581                 if (hook->refcount \
1582                  && hook->itf->hook_session_##what \
1583                  && (hook->flags & afb_hook_flag_session_##what) != 0 \
1584                  && MATCH_SESSION(hook->pattern, (sessid?:(sessid=afb_session_uuid(session))))) { \
1585                         hook->itf->hook_session_##what(hook->closure, &hookid, __VA_ARGS__); \
1586                 } \
1587                 hook = hook->next; \
1588         } \
1589         pthread_rwlock_unlock(&rwlock);
1590
1591 void afb_hook_session_create(struct afb_session *session)
1592 {
1593         _HOOK_SESSION_(create, session);
1594 }
1595
1596 void afb_hook_session_close(struct afb_session *session)
1597 {
1598         _HOOK_SESSION_(close, session);
1599 }
1600
1601 void afb_hook_session_destroy(struct afb_session *session)
1602 {
1603         _HOOK_SESSION_(destroy, session);
1604 }
1605
1606 void afb_hook_session_renew(struct afb_session *session)
1607 {
1608         _HOOK_SESSION_(renew, session);
1609 }
1610
1611 void afb_hook_session_addref(struct afb_session *session)
1612 {
1613         _HOOK_SESSION_(addref, session);
1614 }
1615
1616 void afb_hook_session_unref(struct afb_session *session)
1617 {
1618         _HOOK_SESSION_(unref, session);
1619 }
1620
1621
1622 /******************************************************************************
1623  * section: hooking sessions (session)
1624  *****************************************************************************/
1625
1626 struct afb_hook_session *afb_hook_create_session(const char *pattern, int flags, struct afb_hook_session_itf *itf, void *closure)
1627 {
1628         struct afb_hook_session *hook;
1629
1630         /* alloc the result */
1631         hook = calloc(1, sizeof *hook);
1632         if (hook == NULL)
1633                 return NULL;
1634
1635         /* get a copy of the names */
1636         hook->pattern = pattern ? strdup(pattern) : NULL;
1637         if (pattern && !hook->pattern) {
1638                 free(hook);
1639                 return NULL;
1640         }
1641
1642         /* initialise the rest */
1643         hook->refcount = 1;
1644         hook->flags = flags;
1645         hook->itf = itf ? itf : &hook_session_default_itf;
1646         hook->closure = closure;
1647
1648         /* record the hook */
1649         pthread_mutex_lock(&mutex);
1650         hook->next = list_of_session_hooks;
1651         list_of_session_hooks = hook;
1652         pthread_mutex_unlock(&mutex);
1653
1654         /* returns it */
1655         return hook;
1656 }
1657
1658 struct afb_hook_session *afb_hook_addref_session(struct afb_hook_session *hook)
1659 {
1660         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1661         return hook;
1662 }
1663
1664 static void hook_clean_session()
1665 {
1666         struct afb_hook_session **prv, *hook, *head;
1667
1668         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1669                 /* unlink under mutex */
1670                 head = NULL;
1671                 pthread_mutex_lock(&mutex);
1672                 prv = &list_of_session_hooks;
1673                 while ((hook = *prv)) {
1674                         if (hook->refcount)
1675                                 prv = &(*prv)->next;
1676                         else {
1677                                 *prv = hook->next;
1678                                 hook->next = head;
1679                                 head = hook;
1680                         }
1681                 }
1682                 pthread_mutex_unlock(&mutex);
1683                 pthread_rwlock_unlock(&rwlock);
1684
1685                 /* free found hooks */
1686                 while((hook = head)) {
1687                         head = hook->next;
1688                         free(hook->pattern);
1689                         free(hook);
1690                 }
1691         }
1692 }
1693
1694 void afb_hook_unref_session(struct afb_hook_session *hook)
1695 {
1696         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
1697                 hook_clean_session();
1698 }
1699
1700 /******************************************************************************
1701  * section: default callbacks for globals (global)
1702  *****************************************************************************/
1703
1704 static void _hook_global_(const char *format, ...)
1705 {
1706         va_list ap;
1707         va_start(ap, format);
1708         _hook_("global", format, ap);
1709         va_end(ap);
1710 }
1711
1712 static void hook_global_vverbose_cb(void *closure, const struct afb_hookid *hookid, int level, const char *file, int line, const char *func, const char *fmt, va_list args)
1713 {
1714         int len;
1715         char *msg;
1716         va_list ap;
1717
1718         va_copy(ap, args);
1719         len = vasprintf(&msg, fmt, ap);
1720         va_end(ap);
1721
1722         if (len < 0)
1723                 _hook_global_("vverbose(%d:%s, %s, %d, %s) -> %s ? ? ?", level, verbose_name_of_level(level), file, line, func, fmt);
1724         else {
1725                 _hook_global_("vverbose(%d:%s, %s, %d, %s) -> %s", level, verbose_name_of_level(level), file, line, func, msg);
1726                 free(msg);
1727         }
1728 }
1729
1730 static struct afb_hook_global_itf hook_global_default_itf = {
1731         .hook_global_vverbose = hook_global_vverbose_cb
1732 };
1733
1734 /******************************************************************************
1735  * section: hooks for tracing globals (global)
1736  *****************************************************************************/
1737
1738 #define _HOOK_GLOBAL_(what,...)   \
1739         struct afb_hook_global *hook; \
1740         struct afb_hookid hookid; \
1741         pthread_rwlock_rdlock(&rwlock); \
1742         init_hookid(&hookid); \
1743         hook = list_of_global_hooks; \
1744         while (hook) { \
1745                 if (hook->refcount \
1746                  && hook->itf->hook_global_##what \
1747                  && (hook->flags & afb_hook_flag_global_##what) != 0) { \
1748                         hook->itf->hook_global_##what(hook->closure, &hookid, __VA_ARGS__); \
1749                 } \
1750                 hook = hook->next; \
1751         } \
1752         pthread_rwlock_unlock(&rwlock);
1753
1754 static void afb_hook_global_vverbose(int level, const char *file, int line, const char *func, const char *fmt, va_list args)
1755 {
1756         _HOOK_GLOBAL_(vverbose, level, file ?: "?", line, func ?: "?", fmt ?: "", args);
1757 }
1758
1759 /******************************************************************************
1760  * section: hooking globals (global)
1761  *****************************************************************************/
1762
1763 static void update_global()
1764 {
1765         struct afb_hook_global *hook;
1766         int flags = 0;
1767
1768         pthread_rwlock_rdlock(&rwlock);
1769         hook = list_of_global_hooks;
1770         while (hook) {
1771                 if (hook->refcount)
1772                         flags = hook->flags;
1773                 hook = hook->next;
1774         }
1775         verbose_observer = (flags & afb_hook_flag_global_vverbose) ? afb_hook_global_vverbose : NULL;
1776         pthread_rwlock_unlock(&rwlock);
1777 }
1778
1779 struct afb_hook_global *afb_hook_create_global(int flags, struct afb_hook_global_itf *itf, void *closure)
1780 {
1781         struct afb_hook_global *hook;
1782
1783         /* alloc the result */
1784         hook = calloc(1, sizeof *hook);
1785         if (hook == NULL)
1786                 return NULL;
1787
1788         /* initialise the rest */
1789         hook->refcount = 1;
1790         hook->flags = flags;
1791         hook->itf = itf ? itf : &hook_global_default_itf;
1792         hook->closure = closure;
1793
1794         /* record the hook */
1795         pthread_mutex_lock(&mutex);
1796         hook->next = list_of_global_hooks;
1797         list_of_global_hooks = hook;
1798         pthread_mutex_unlock(&mutex);
1799
1800         /* update hooking */
1801         update_global();
1802
1803         /* returns it */
1804         return hook;
1805 }
1806
1807 struct afb_hook_global *afb_hook_addref_global(struct afb_hook_global *hook)
1808 {
1809         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1810         return hook;
1811 }
1812
1813 static void hook_clean_global()
1814 {
1815         struct afb_hook_global **prv, *hook, *head;
1816
1817         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1818                 /* unlink under mutex */
1819                 head = NULL;
1820                 pthread_mutex_lock(&mutex);
1821                 prv = &list_of_global_hooks;
1822                 while ((hook = *prv)) {
1823                         if (hook->refcount)
1824                                 prv = &(*prv)->next;
1825                         else {
1826                                 *prv = hook->next;
1827                                 hook->next = head;
1828                                 head = hook;
1829                         }
1830                 }
1831                 pthread_mutex_unlock(&mutex);
1832                 pthread_rwlock_unlock(&rwlock);
1833
1834                 /* free found hooks */
1835                 while((hook = head)) {
1836                         head = hook->next;
1837                         free(hook);
1838                 }
1839         }
1840 }
1841
1842 void afb_hook_unref_global(struct afb_hook_global *hook)
1843 {
1844         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED)) {
1845                 /* update hooking */
1846                 update_global();
1847                 hook_clean_global();
1848         }
1849 }
1850