src/afb-hook.c

   1 /*
   2  * Copyright (C) 2015-2020 "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 #if WITH_AFB_HOOK  /***********************************************************/
  19
  20 #define _GNU_SOURCE
  21
  22 #include <limits.h>
  23 #include <stdio.h>
  24 #include <stdarg.h>
  25 #include <string.h>
  26 #include <pthread.h>
  27 #include <unistd.h>
  28 #include <sys/uio.h>
  29
  30 #include <json-c/json.h>
  31 #if !defined(JSON_C_TO_STRING_NOSLASHESCAPE)
  32 #define JSON_C_TO_STRING_NOSLASHESCAPE 0
  33 #endif
  34
  35 #include <afb/afb-req-x1.h>
  36 #include <afb/afb-event-x2.h>
  37
  38 #include "afb-context.h"
  39 #include "afb-hook.h"
  40 #include "afb-session.h"
  41 #include "afb-cred.h"
  42 #include "afb-xreq.h"
  43 #include "afb-export.h"
  44 #include "afb-evt.h"
  45 #include "afb-api.h"
  46 #include "afb-msg-json.h"
  47 #include "verbose.h"
  48
  49 #include <fnmatch.h>
  50 #define MATCH(pattern,string)   (\
  51                 pattern \
  52                         ? !fnmatch((pattern),(string),FNM_CASEFOLD|FNM_EXTMATCH|FNM_PERIOD) \
  53                         : afb_api_is_public(string))
  54
  55 #define MATCH_API(pattern,string)       MATCH(pattern,string)
  56 #define MATCH_VERB(pattern,string)      MATCH(pattern,string)
  57 #define MATCH_EVENT(pattern,string)     MATCH(pattern,string)
  58 #define MATCH_SESSION(pattern,string)   MATCH(pattern,string)
  59
  60 /**
  61  * Definition of a hook for xreq
  62  */
  63 struct afb_hook_xreq {
  64         struct afb_hook_xreq *next; /**< next hook */
  65         unsigned refcount; /**< reference count */
  66         unsigned flags; /**< hook flags */
  67         char *api; /**< api hooked or NULL for any */
  68         char *verb; /**< verb hooked or NULL for any */
  69         struct afb_session *session; /**< session hooked or NULL if any */
  70         struct afb_hook_xreq_itf *itf; /**< interface of hook */
  71         void *closure; /**< closure for callbacks */
  72 };
  73
  74 /**
  75  * Definition of a hook for export
  76  */
  77 struct afb_hook_api {
  78         struct afb_hook_api *next; /**< next hook */
  79         unsigned refcount; /**< reference count */
  80         unsigned flags; /**< hook flags */
  81         char *api; /**< api hooked or NULL for any */
  82         struct afb_hook_api_itf *itf; /**< interface of hook */
  83         void *closure; /**< closure for callbacks */
  84 };
  85
  86 /**
  87  * Definition of a hook for evt
  88  */
  89 struct afb_hook_evt {
  90         struct afb_hook_evt *next; /**< next hook */
  91         unsigned refcount; /**< reference count */
  92         unsigned flags; /**< hook flags */
  93         char *pattern; /**< event pattern name hooked or NULL for any */
  94         struct afb_hook_evt_itf *itf; /**< interface of hook */
  95         void *closure; /**< closure for callbacks */
  96 };
  97
  98 /**
  99  * Definition of a hook for session
 100  */
 101 struct afb_hook_session {
 102         struct afb_hook_session *next; /**< next hook */
 103         unsigned refcount; /**< reference count */
 104         unsigned flags; /**< hook flags */
 105         char *pattern; /**< event pattern name hooked or NULL for any */
 106         struct afb_hook_session_itf *itf; /**< interface of hook */
 107         void *closure; /**< closure for callbacks */
 108 };
 109
 110 /**
 111  * Definition of a hook for global
 112  */
 113 struct afb_hook_global {
 114         struct afb_hook_global *next; /**< next hook */
 115         unsigned refcount; /**< reference count */
 116         unsigned flags; /**< hook flags */
 117         struct afb_hook_global_itf *itf; /**< interface of hook */
 118         void *closure; /**< closure for callbacks */
 119 };
 120
 121 /* synchronization across threads */
 122 static pthread_rwlock_t rwlock = PTHREAD_RWLOCK_INITIALIZER;
 123 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 124
 125 /* list of hooks for xreq */
 126 static struct afb_hook_xreq *list_of_xreq_hooks = NULL;
 127
 128 /* list of hooks for export */
 129 static struct afb_hook_api *list_of_api_hooks = NULL;
 130
 131 /* list of hooks for evt */
 132 static struct afb_hook_evt *list_of_evt_hooks = NULL;
 133
 134 /* list of hooks for session */
 135 static struct afb_hook_session *list_of_session_hooks = NULL;
 136
 137 /* list of hooks for global */
 138 static struct afb_hook_global *list_of_global_hooks = NULL;
 139
 140 /* hook id */
 141 static unsigned next_hookid = 0;
 142
 143 /******************************************************************************
 144  * section: hook id
 145  *****************************************************************************/
 146 static void init_hookid(struct afb_hookid *hookid)
 147 {
 148         hookid->id = __atomic_add_fetch(&next_hookid, 1, __ATOMIC_RELAXED);
 149         clock_gettime(CLOCK_REALTIME, &hookid->time);
 150 }
 151
 152 /******************************************************************************
 153  * section: default callbacks for tracing requests
 154  *****************************************************************************/
 155
 156 static char *_pbuf_(const char *fmt, va_list args, char **palloc, char *sbuf, size_t szsbuf, size_t *outlen)
 157 {
 158         int rc;
 159         va_list cp;
 160
 161         *palloc = NULL;
 162         va_copy(cp, args);
 163         rc = vsnprintf(sbuf, szsbuf, fmt, args);
 164         if ((size_t)rc >= szsbuf) {
 165                 sbuf[szsbuf-1] = 0;
 166                 sbuf[szsbuf-2] = sbuf[szsbuf-3] = sbuf[szsbuf-4] = '.';
 167                 rc = vasprintf(palloc, fmt, cp);
 168                 if (rc >= 0)
 169                         sbuf = *palloc;
 170         }
 171         va_end(cp);
 172         if (rc >= 0 && outlen)
 173                 *outlen = (size_t)rc;
 174         return sbuf;
 175 }
 176
 177 static void _hook_(const char *fmt1, const char *fmt2, va_list arg2, ...)
 178 {
 179         static const char chars[] = "HOOK: [] \n";
 180         char *mem1, *mem2, buf1[256], buf2[2000];
 181         struct iovec iov[5];
 182         va_list arg1;
 183
 184         /* "HOOK: [" */
 185         iov[0].iov_base = (void*)&chars[0];
 186         iov[0].iov_len = 7;
 187
 188         /* fmt1 ... */
 189         va_start(arg1, arg2);
 190         iov[1].iov_base = _pbuf_(fmt1, arg1, &mem1, buf1, sizeof buf1, &iov[1].iov_len);
 191         va_end(arg1);
 192
 193         /* "] " */
 194         iov[2].iov_base = (void*)&chars[7];
 195         iov[2].iov_len = 2;
 196
 197         /* fmt2 arg2 */
 198         iov[3].iov_base = _pbuf_(fmt2, arg2, &mem2, buf2, sizeof buf2, &iov[3].iov_len);
 199
 200         /* "\n" */
 201         iov[4].iov_base = (void*)&chars[9];
 202         iov[4].iov_len = 1;
 203
 204         (void)writev(2, iov, 5);
 205
 206         free(mem1);
 207         free(mem2);
 208 }
 209
 210 static void _hook_xreq_(const struct afb_xreq *xreq, const char *format, ...)
 211 {
 212         va_list ap;
 213         va_start(ap, format);
 214         _hook_("xreq-%06d:%s/%s", format, ap, xreq->hookindex, xreq->request.called_api, xreq->request.called_verb);
 215         va_end(ap);
 216 }
 217
 218 static void hook_xreq_begin_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 219 {
 220         struct afb_cred *cred = xreq->context.credentials;
 221
 222         if (!cred)
 223                 _hook_xreq_(xreq, "BEGIN");
 224         else
 225                 _hook_xreq_(xreq, "BEGIN uid=%d=%s gid=%d pid=%d label=%s id=%s",
 226                         (int)cred->uid,
 227                         cred->user,
 228                         (int)cred->gid,
 229                         (int)cred->pid,
 230                         cred->label?:"(null)",
 231                         cred->id?:"(null)"
 232                 );
 233 }
 234
 235 static void hook_xreq_end_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 236 {
 237         _hook_xreq_(xreq, "END");
 238 }
 239
 240 static void hook_xreq_json_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *obj)
 241 {
 242         _hook_xreq_(xreq, "json() -> %s", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE));
 243 }
 244
 245 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)
 246 {
 247         _hook_xreq_(xreq, "get(%s) -> { name: %s, value: %s, path: %s }", name, arg.name, arg.value, arg.path);
 248 }
 249
 250 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)
 251 {
 252         _hook_xreq_(xreq, "reply[%s](%s, %s)", error?:"success", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE), info);
 253 }
 254
 255 static void hook_xreq_legacy_context_get_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, void *value)
 256 {
 257         _hook_xreq_(xreq, "context_get() -> %p", value);
 258 }
 259
 260 static void hook_xreq_legacy_context_set_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, void *value, void (*free_value)(void*))
 261 {
 262         _hook_xreq_(xreq, "context_set(%p, %p)", value, free_value);
 263 }
 264
 265 static void hook_xreq_addref_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 266 {
 267         _hook_xreq_(xreq, "addref()");
 268 }
 269
 270 static void hook_xreq_unref_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 271 {
 272         _hook_xreq_(xreq, "unref()");
 273 }
 274
 275 static void hook_xreq_session_close_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 276 {
 277         _hook_xreq_(xreq, "session_close()");
 278 }
 279
 280 static void hook_xreq_session_set_LOA_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, unsigned level, int result)
 281 {
 282         _hook_xreq_(xreq, "session_set_LOA(%u) -> %d", level, result);
 283 }
 284
 285 static void hook_xreq_subscribe_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_event_x2 *event_x2, int result)
 286 {
 287         _hook_xreq_(xreq, "subscribe(%s:%d) -> %d", afb_evt_event_x2_fullname(event_x2), afb_evt_event_x2_id(event_x2), result);
 288 }
 289
 290 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)
 291 {
 292         _hook_xreq_(xreq, "unsubscribe(%s:%d) -> %d", afb_evt_event_x2_fullname(event_x2), afb_evt_event_x2_id(event_x2), result);
 293 }
 294
 295 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)
 296 {
 297         _hook_xreq_(xreq, "subcall(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 298 }
 299
 300 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)
 301 {
 302         _hook_xreq_(xreq, "    ...subcall... [%s] -> %s (%s)", error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 303 }
 304
 305 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)
 306 {
 307         _hook_xreq_(xreq, "subcallsync(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 308 }
 309
 310 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)
 311 {
 312         _hook_xreq_(xreq, "    ...subcallsync... %d [%s] -> %s (%s)", status, error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 313 }
 314
 315 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)
 316 {
 317         int len;
 318         char *msg;
 319         va_list ap;
 320
 321         va_copy(ap, args);
 322         len = vasprintf(&msg, fmt, ap);
 323         va_end(ap);
 324
 325         if (len < 0)
 326                 _hook_xreq_(xreq, "vverbose(%d:%s, %s, %d, %s) -> %s ? ? ?", level, verbose_name_of_level(level), file, line, func, fmt);
 327         else {
 328                 _hook_xreq_(xreq, "vverbose(%d:%s, %s, %d, %s) -> %s", level, verbose_name_of_level(level), file, line, func, msg);
 329                 free(msg);
 330         }
 331 }
 332
 333 static void hook_xreq_legacy_store_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct afb_stored_req *sreq)
 334 {
 335         _hook_xreq_(xreq, "store() -> %p", sreq);
 336 }
 337
 338 static void hook_xreq_legacy_unstore_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq)
 339 {
 340         _hook_xreq_(xreq, "unstore()");
 341 }
 342
 343 static void hook_xreq_has_permission_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, const char *permission, int result)
 344 {
 345         _hook_xreq_(xreq, "has_permission(%s) -> %d", permission, result);
 346 }
 347
 348 static void hook_xreq_get_application_id_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, char *result)
 349 {
 350         _hook_xreq_(xreq, "get_application_id() -> %s", result);
 351 }
 352
 353 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)
 354 {
 355         _hook_xreq_(xreq, "context_make(replace=%s, %p, %p, %p) -> %p", replace?"yes":"no", create_value, free_value, create_closure, result);
 356 }
 357
 358 static void hook_xreq_get_uid_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, int result)
 359 {
 360         _hook_xreq_(xreq, "get_uid() -> %d", result);
 361 }
 362
 363 static void hook_xreq_get_client_info_cb(void *closure, const struct afb_hookid *hookid, const struct afb_xreq *xreq, struct json_object *result)
 364 {
 365         _hook_xreq_(xreq, "get_client_info() -> %s", json_object_to_json_string_ext(result, JSON_C_TO_STRING_NOSLASHESCAPE));
 366 }
 367
 368 static struct afb_hook_xreq_itf hook_xreq_default_itf = {
 369         .hook_xreq_begin = hook_xreq_begin_cb,
 370         .hook_xreq_end = hook_xreq_end_cb,
 371         .hook_xreq_json = hook_xreq_json_cb,
 372         .hook_xreq_get = hook_xreq_get_cb,
 373         .hook_xreq_reply = hook_xreq_reply_cb,
 374         .hook_xreq_legacy_context_get = hook_xreq_legacy_context_get_cb,
 375         .hook_xreq_legacy_context_set = hook_xreq_legacy_context_set_cb,
 376         .hook_xreq_addref = hook_xreq_addref_cb,
 377         .hook_xreq_unref = hook_xreq_unref_cb,
 378         .hook_xreq_session_close = hook_xreq_session_close_cb,
 379         .hook_xreq_session_set_LOA = hook_xreq_session_set_LOA_cb,
 380         .hook_xreq_subscribe = hook_xreq_subscribe_cb,
 381         .hook_xreq_unsubscribe = hook_xreq_unsubscribe_cb,
 382         .hook_xreq_subcall = hook_xreq_subcall_cb,
 383         .hook_xreq_subcall_result = hook_xreq_subcall_result_cb,
 384         .hook_xreq_subcallsync = hook_xreq_subcallsync_cb,
 385         .hook_xreq_subcallsync_result = hook_xreq_subcallsync_result_cb,
 386         .hook_xreq_vverbose = hook_xreq_vverbose_cb,
 387         .hook_xreq_legacy_store = hook_xreq_legacy_store_cb,
 388         .hook_xreq_legacy_unstore = hook_xreq_legacy_unstore_cb,
 389         .hook_xreq_has_permission = hook_xreq_has_permission_cb,
 390         .hook_xreq_get_application_id = hook_xreq_get_application_id_cb,
 391         .hook_xreq_context_make = hook_xreq_context_make_cb,
 392         .hook_xreq_get_uid = hook_xreq_get_uid_cb,
 393         .hook_xreq_get_client_info = hook_xreq_get_client_info_cb,
 394 };
 395
 396 /******************************************************************************
 397  * section: hooks for tracing requests
 398  *****************************************************************************/
 399
 400 #define _HOOK_XREQ_2_(flag,func,...)   \
 401         struct afb_hook_xreq *hook; \
 402         struct afb_hookid hookid; \
 403         pthread_rwlock_rdlock(&rwlock); \
 404         init_hookid(&hookid); \
 405         hook = list_of_xreq_hooks; \
 406         while (hook) { \
 407                 if (hook->refcount \
 408                  && hook->itf->hook_xreq_##func \
 409                  && (hook->flags & afb_hook_flag_req_##flag) != 0 \
 410                  && (!hook->session || hook->session == xreq->context.session) \
 411                  && MATCH_API(hook->api, xreq->request.called_api) \
 412                  && MATCH_VERB(hook->verb, xreq->request.called_verb)) { \
 413                         hook->itf->hook_xreq_##func(hook->closure, &hookid, __VA_ARGS__); \
 414                 } \
 415                 hook = hook->next; \
 416         } \
 417         pthread_rwlock_unlock(&rwlock);
 418
 419 #define _HOOK_XREQ_(what,...)   _HOOK_XREQ_2_(what,what,__VA_ARGS__)
 420
 421 void afb_hook_xreq_begin(const struct afb_xreq *xreq)
 422 {
 423         _HOOK_XREQ_(begin, xreq);
 424 }
 425
 426 void afb_hook_xreq_end(const struct afb_xreq *xreq)
 427 {
 428         _HOOK_XREQ_(end, xreq);
 429 }
 430
 431 struct json_object *afb_hook_xreq_json(const struct afb_xreq *xreq, struct json_object *obj)
 432 {
 433         _HOOK_XREQ_(json, xreq, obj);
 434         return obj;
 435 }
 436
 437 struct afb_arg afb_hook_xreq_get(const struct afb_xreq *xreq, const char *name, struct afb_arg arg)
 438 {
 439         _HOOK_XREQ_(get, xreq, name, arg);
 440         return arg;
 441 }
 442
 443 void afb_hook_xreq_reply(const struct afb_xreq *xreq, struct json_object *obj, const char *error, const char *info)
 444 {
 445         _HOOK_XREQ_(reply, xreq, obj, error, info);
 446 }
 447
 448 void *afb_hook_xreq_legacy_context_get(const struct afb_xreq *xreq, void *value)
 449 {
 450         _HOOK_XREQ_(legacy_context_get, xreq, value);
 451         return value;
 452 }
 453
 454 void afb_hook_xreq_legacy_context_set(const struct afb_xreq *xreq, void *value, void (*free_value)(void*))
 455 {
 456         _HOOK_XREQ_(legacy_context_set, xreq, value, free_value);
 457 }
 458
 459 void afb_hook_xreq_addref(const struct afb_xreq *xreq)
 460 {
 461         _HOOK_XREQ_(addref, xreq);
 462 }
 463
 464 void afb_hook_xreq_unref(const struct afb_xreq *xreq)
 465 {
 466         _HOOK_XREQ_(unref, xreq);
 467 }
 468
 469 void afb_hook_xreq_session_close(const struct afb_xreq *xreq)
 470 {
 471         _HOOK_XREQ_(session_close, xreq);
 472 }
 473
 474 int afb_hook_xreq_session_set_LOA(const struct afb_xreq *xreq, unsigned level, int result)
 475 {
 476         _HOOK_XREQ_(session_set_LOA, xreq, level, result);
 477         return result;
 478 }
 479
 480 int afb_hook_xreq_subscribe(const struct afb_xreq *xreq, struct afb_event_x2 *event_x2, int result)
 481 {
 482         _HOOK_XREQ_(subscribe, xreq, event_x2, result);
 483         return result;
 484 }
 485
 486 int afb_hook_xreq_unsubscribe(const struct afb_xreq *xreq, struct afb_event_x2 *event_x2, int result)
 487 {
 488         _HOOK_XREQ_(unsubscribe, xreq, event_x2, result);
 489         return result;
 490 }
 491
 492 void afb_hook_xreq_subcall(const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args, int flags)
 493 {
 494         _HOOK_XREQ_(subcall, xreq, api, verb, args);
 495 }
 496
 497 void afb_hook_xreq_subcall_result(const struct afb_xreq *xreq, struct json_object *object, const char *error, const char *info)
 498 {
 499         _HOOK_XREQ_(subcall_result, xreq, object, error, info);
 500 }
 501
 502 void afb_hook_xreq_subcallsync(const struct afb_xreq *xreq, const char *api, const char *verb, struct json_object *args, int flags)
 503 {
 504         _HOOK_XREQ_(subcallsync, xreq, api, verb, args);
 505 }
 506
 507 int  afb_hook_xreq_subcallsync_result(const struct afb_xreq *xreq, int status, struct json_object *object, const char *error, const char *info)
 508 {
 509         _HOOK_XREQ_(subcallsync_result, xreq, status, object, error, info);
 510         return status;
 511 }
 512
 513 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)
 514 {
 515         _HOOK_XREQ_(vverbose, xreq, level, file ?: "?", line, func ?: "?", fmt, args);
 516 }
 517
 518 void afb_hook_xreq_legacy_store(const struct afb_xreq *xreq, struct afb_stored_req *sreq)
 519 {
 520         _HOOK_XREQ_(legacy_store, xreq, sreq);
 521 }
 522
 523 void afb_hook_xreq_legacy_unstore(const struct afb_xreq *xreq)
 524 {
 525         _HOOK_XREQ_(legacy_unstore, xreq);
 526 }
 527
 528 int afb_hook_xreq_has_permission(const struct afb_xreq *xreq, const char *permission, int result)
 529 {
 530         _HOOK_XREQ_(has_permission, xreq, permission, result);
 531         return result;
 532 }
 533
 534 char *afb_hook_xreq_get_application_id(const struct afb_xreq *xreq, char *result)
 535 {
 536         _HOOK_XREQ_(get_application_id, xreq, result);
 537         return result;
 538 }
 539
 540 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)
 541 {
 542         _HOOK_XREQ_(context_make, xreq, replace, create_value, free_value, create_closure, result);
 543         return result;
 544 }
 545
 546 int afb_hook_xreq_get_uid(const struct afb_xreq *xreq, int result)
 547 {
 548         _HOOK_XREQ_(get_uid, xreq, result);
 549         return result;
 550 }
 551
 552 struct json_object *afb_hook_xreq_get_client_info(const struct afb_xreq *xreq, struct json_object *result)
 553 {
 554         _HOOK_XREQ_(get_client_info, xreq, result);
 555         return result;
 556 }
 557
 558 /******************************************************************************
 559  * section: hooking xreqs
 560  *****************************************************************************/
 561
 562 void afb_hook_init_xreq(struct afb_xreq *xreq)
 563 {
 564         static int reqindex = 0;
 565
 566         int f, flags;
 567         int add, x;
 568         struct afb_hook_xreq *hook;
 569
 570         /* scan hook list to get the expected flags */
 571         flags = 0;
 572         pthread_rwlock_rdlock(&rwlock);
 573         hook = list_of_xreq_hooks;
 574         while (hook) {
 575                 f = hook->flags & afb_hook_flags_req_all;
 576                 add = f != 0
 577                    && (!hook->session || hook->session == xreq->context.session)
 578                    && MATCH_API(hook->api, xreq->request.called_api)
 579                    && MATCH_VERB(hook->verb, xreq->request.called_verb);
 580                 if (add)
 581                         flags |= f;
 582                 hook = hook->next;
 583         }
 584         pthread_rwlock_unlock(&rwlock);
 585
 586         /* store the hooking data */
 587         xreq->hookflags = flags;
 588         if (flags) {
 589                 do {
 590                         x = __atomic_load_n(&reqindex, __ATOMIC_RELAXED);
 591                         xreq->hookindex = (x + 1) % 1000000 ?: 1;
 592                 } while (x != __atomic_exchange_n(&reqindex, xreq->hookindex, __ATOMIC_RELAXED));
 593         }
 594 }
 595
 596 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)
 597 {
 598         struct afb_hook_xreq *hook;
 599
 600         /* alloc the result */
 601         hook = calloc(1, sizeof *hook);
 602         if (hook == NULL)
 603                 return NULL;
 604
 605         /* get a copy of the names */
 606         hook->api = api ? strdup(api) : NULL;
 607         hook->verb = verb ? strdup(verb) : NULL;
 608         if ((api && !hook->api) || (verb && !hook->verb)) {
 609                 free(hook->api);
 610                 free(hook->verb);
 611                 free(hook);
 612                 return NULL;
 613         }
 614
 615         /* initialise the rest */
 616         hook->session = session;
 617         if (session)
 618                 afb_session_addref(session);
 619         hook->refcount = 1;
 620         hook->flags = flags;
 621         hook->itf = itf ? itf : &hook_xreq_default_itf;
 622         hook->closure = closure;
 623
 624         /* record the hook */
 625         pthread_mutex_lock(&mutex);
 626         hook->next = list_of_xreq_hooks;
 627         list_of_xreq_hooks = hook;
 628         pthread_mutex_unlock(&mutex);
 629
 630         /* returns it */
 631         return hook;
 632 }
 633
 634 struct afb_hook_xreq *afb_hook_addref_xreq(struct afb_hook_xreq *hook)
 635 {
 636         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
 637         return hook;
 638 }
 639
 640 static void hook_clean_xreq()
 641 {
 642         struct afb_hook_xreq **prv, *hook, *head;
 643
 644         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
 645                 /* unlink under mutex */
 646                 head = NULL;
 647                 pthread_mutex_lock(&mutex);
 648                 prv = &list_of_xreq_hooks;
 649                 while ((hook = *prv)) {
 650                         if (hook->refcount)
 651                                 prv = &(*prv)->next;
 652                         else {
 653                                 *prv = hook->next;
 654                                 hook->next = head;
 655                                 head = hook;
 656                         }
 657                 }
 658                 pthread_mutex_unlock(&mutex);
 659                 pthread_rwlock_unlock(&rwlock);
 660
 661                 /* free found hooks */
 662                 while((hook = head)) {
 663                         head = hook->next;
 664                         free(hook->api);
 665                         free(hook->verb);
 666                         if (hook->session)
 667                                 afb_session_unref(hook->session);
 668                         free(hook);
 669                 }
 670         }
 671 }
 672
 673 void afb_hook_unref_xreq(struct afb_hook_xreq *hook)
 674 {
 675         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
 676                 hook_clean_xreq();
 677 }
 678
 679 /******************************************************************************
 680  * section: default callbacks for tracing daemon interface
 681  *****************************************************************************/
 682
 683 static void _hook_api_(const struct afb_export *export, const char *format, ...)
 684 {
 685         va_list ap;
 686         va_start(ap, format);
 687         _hook_("api-%s", format, ap, afb_export_apiname(export));
 688         va_end(ap);
 689 }
 690
 691 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)
 692 {
 693         _hook_api_(export, "event_broadcast.before(%s, %s)....", name, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 694 }
 695
 696 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)
 697 {
 698         _hook_api_(export, "event_broadcast.after(%s, %s) -> %d", name, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), result);
 699 }
 700
 701 static void hook_api_get_event_loop_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct sd_event *result)
 702 {
 703         _hook_api_(export, "get_event_loop() -> %p", result);
 704 }
 705
 706 static void hook_api_get_user_bus_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct sd_bus *result)
 707 {
 708         _hook_api_(export, "get_user_bus() -> %p", result);
 709 }
 710
 711 static void hook_api_get_system_bus_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct sd_bus *result)
 712 {
 713         _hook_api_(export, "get_system_bus() -> %p", result);
 714 }
 715
 716 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)
 717 {
 718         int len;
 719         char *msg;
 720         va_list ap;
 721
 722         va_copy(ap, args);
 723         len = vasprintf(&msg, fmt, ap);
 724         va_end(ap);
 725
 726         if (len < 0)
 727                 _hook_api_(export, "vverbose(%d:%s, %s, %d, %s) -> %s ? ? ?", level, verbose_name_of_level(level), file, line, function, fmt);
 728         else {
 729                 _hook_api_(export, "vverbose(%d:%s, %s, %d, %s) -> %s", level, verbose_name_of_level(level), file, line, function, msg);
 730                 free(msg);
 731         }
 732 }
 733
 734 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)
 735 {
 736         _hook_api_(export, "event_make(%s) -> %s:%d", name, afb_evt_event_x2_fullname(result), afb_evt_event_x2_id(result));
 737 }
 738
 739 static void hook_api_rootdir_get_fd_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 740 {
 741         char path[PATH_MAX], proc[100];
 742         ssize_t s;
 743
 744         if (result < 0)
 745                 _hook_api_(export, "rootdir_get_fd() -> %d, %m", result);
 746         else {
 747                 snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
 748                 s = readlink(proc, path, sizeof path);
 749                 path[s < 0 ? 0 : s >= sizeof path ? sizeof path - 1 : s] = 0;
 750                 _hook_api_(export, "rootdir_get_fd() -> %d = %s", result, path);
 751         }
 752 }
 753
 754 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)
 755 {
 756         char path[PATH_MAX], proc[100];
 757         ssize_t s;
 758
 759         if (!locale)
 760                 locale = "(null)";
 761         if (result < 0)
 762                 _hook_api_(export, "rootdir_open_locale(%s, %d, %s) -> %d, %m", filename, flags, locale, result);
 763         else {
 764                 snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
 765                 s = readlink(proc, path, sizeof path);
 766                 path[s < 0 ? 0 : s >= sizeof path ? sizeof path - 1 : s] = 0;
 767                 _hook_api_(export, "rootdir_open_locale(%s, %d, %s) -> %d = %s", filename, flags, locale, result, path);
 768         }
 769 }
 770
 771 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)
 772 {
 773         _hook_api_(export, "queue_job(%p, %p, %p, %d) -> %d", callback, argument, group, timeout, result);
 774 }
 775
 776 static void hook_api_unstore_req_cb(void *closure, const struct afb_hookid *hookid,  const struct afb_export *export, struct afb_stored_req *sreq)
 777 {
 778         _hook_api_(export, "unstore_req(%p)", sreq);
 779 }
 780
 781 static void hook_api_require_api_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *name, int initialized)
 782 {
 783         _hook_api_(export, "require_api(%s, %d)...", name, initialized);
 784 }
 785
 786 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)
 787 {
 788         _hook_api_(export, "...require_api(%s, %d) -> %d", name, initialized, result);
 789 }
 790
 791 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)
 792 {
 793         _hook_api_(export, "add_alias(%s -> %s) -> %d", api, alias?:"<null>", result);
 794 }
 795
 796 static void hook_api_start_before_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export)
 797 {
 798         _hook_api_(export, "start.before");
 799 }
 800
 801 static void hook_api_start_after_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int status)
 802 {
 803         _hook_api_(export, "start.after -> %d", status);
 804 }
 805
 806 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)
 807 {
 808         _hook_api_(export, "on_event.before(%s, %d, %s)", event, event_x2, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 809 }
 810
 811 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)
 812 {
 813         _hook_api_(export, "on_event.after(%s, %d, %s)", event, event_x2, json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 814 }
 815
 816 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)
 817 {
 818         _hook_api_(export, "call(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 819 }
 820
 821 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)
 822 {
 823         _hook_api_(export, "    ...call... [%s] -> %s (%s)", error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 824 }
 825
 826 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)
 827 {
 828         _hook_api_(export, "callsync(%s/%s, %s) ...", api, verb, json_object_to_json_string_ext(args, JSON_C_TO_STRING_NOSLASHESCAPE));
 829 }
 830
 831 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)
 832 {
 833         _hook_api_(export, "    ...callsync... %d [%s] -> %s (%s)", status, error?:"success", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE), info?:"");
 834 }
 835
 836 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)
 837 {
 838         _hook_api_(export, "new_api.before %s (%s)%s ...", api, info?:"", noconcurrency?" no-concurrency" : "");
 839 }
 840
 841 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)
 842 {
 843         _hook_api_(export, "... new_api.after %s -> %s (%d)", api, result >= 0 ? "OK" : "ERROR", result);
 844 }
 845
 846 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)
 847 {
 848         _hook_api_(export, "set_verbs_v2 -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 849 }
 850
 851 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)
 852 {
 853         _hook_api_(export, "set_verbs_v3 -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 854 }
 855
 856 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)
 857 {
 858         _hook_api_(export, "add_verb(%s%s [%s]) -> %s (%d)", verb, glob?" (GLOB)":"", info?:"", result >= 0 ? "OK" : "ERROR", result);
 859 }
 860
 861 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)
 862 {
 863         _hook_api_(export, "del_verb(%s) -> %s (%d)", verb, result >= 0 ? "OK" : "ERROR", result);
 864 }
 865
 866 static void hook_api_api_set_on_event_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 867 {
 868         _hook_api_(export, "set_on_event -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 869 }
 870
 871 static void hook_api_api_set_on_init_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 872 {
 873         _hook_api_(export, "set_on_init -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 874 }
 875
 876 static void hook_api_api_seal_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export)
 877 {
 878         _hook_api_(export, "seal");
 879 }
 880
 881 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)
 882 {
 883         _hook_api_(export, "event_handler_add(%s) -> %s (%d)", pattern, result >= 0 ? "OK" : "ERROR", result);
 884 }
 885
 886 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)
 887 {
 888         _hook_api_(export, "event_handler_del(%s) -> %s (%d)", pattern, result >= 0 ? "OK" : "ERROR", result);
 889 }
 890
 891 static void hook_api_class_provide_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *name)
 892 {
 893         _hook_api_(export, "class_provide(%s) -> %s (%d)", name, result >= 0 ? "OK" : "ERROR", result);
 894 }
 895
 896 static void hook_api_class_require_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result, const char *name)
 897 {
 898         _hook_api_(export, "class_require(%s) -> %s (%d)", name, result >= 0 ? "OK" : "ERROR", result);
 899 }
 900
 901 static void hook_api_delete_api_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 902 {
 903         _hook_api_(export, "delete_api -> %s (%d)", result >= 0 ? "OK" : "ERROR", result);
 904 }
 905
 906 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)
 907 {
 908         _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));
 909 }
 910
 911 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)
 912 {
 913         _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));
 914 }
 915
 916 static void hook_api_settings_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, struct json_object *object)
 917 {
 918         _hook_api_(export, "settings -> %s", json_object_to_json_string_ext(object, JSON_C_TO_STRING_NOSLASHESCAPE));
 919 }
 920
 921 static struct afb_hook_api_itf hook_api_default_itf = {
 922         .hook_api_event_broadcast_before = hook_api_event_broadcast_before_cb,
 923         .hook_api_event_broadcast_after = hook_api_event_broadcast_after_cb,
 924         .hook_api_get_event_loop = hook_api_get_event_loop_cb,
 925         .hook_api_get_user_bus = hook_api_get_user_bus_cb,
 926         .hook_api_get_system_bus = hook_api_get_system_bus_cb,
 927         .hook_api_vverbose = hook_api_vverbose_cb,
 928         .hook_api_event_make = hook_api_event_make_cb,
 929         .hook_api_rootdir_get_fd = hook_api_rootdir_get_fd_cb,
 930         .hook_api_rootdir_open_locale = hook_api_rootdir_open_locale_cb,
 931         .hook_api_queue_job = hook_api_queue_job_cb,
 932         .hook_api_legacy_unstore_req = hook_api_unstore_req_cb,
 933         .hook_api_require_api = hook_api_require_api_cb,
 934         .hook_api_require_api_result = hook_api_require_api_result_cb,
 935         .hook_api_add_alias = hook_api_add_alias_cb,
 936         .hook_api_start_before = hook_api_start_before_cb,
 937         .hook_api_start_after = hook_api_start_after_cb,
 938         .hook_api_on_event_before = hook_api_on_event_before_cb,
 939         .hook_api_on_event_after = hook_api_on_event_after_cb,
 940         .hook_api_call = hook_api_call_cb,
 941         .hook_api_call_result = hook_api_call_result_cb,
 942         .hook_api_callsync = hook_api_callsync_cb,
 943         .hook_api_callsync_result = hook_api_callsync_result_cb,
 944         .hook_api_new_api_before = hook_api_new_api_before_cb,
 945         .hook_api_new_api_after = hook_api_new_api_after_cb,
 946         .hook_api_api_set_verbs_v2 = hook_api_api_set_verbs_v2_cb,
 947         .hook_api_api_set_verbs_v3 = hook_api_api_set_verbs_v3_cb,
 948         .hook_api_api_add_verb = hook_api_api_add_verb_cb,
 949         .hook_api_api_del_verb = hook_api_api_del_verb_cb,
 950         .hook_api_api_set_on_event = hook_api_api_set_on_event_cb,
 951         .hook_api_api_set_on_init = hook_api_api_set_on_init_cb,
 952         .hook_api_api_seal = hook_api_api_seal_cb,
 953         .hook_api_event_handler_add = hook_api_event_handler_add_cb,
 954         .hook_api_event_handler_del = hook_api_event_handler_del_cb,
 955         .hook_api_class_provide = hook_api_class_provide_cb,
 956         .hook_api_class_require = hook_api_class_require_cb,
 957         .hook_api_delete_api = hook_api_delete_api_cb,
 958         .hook_api_on_event_handler_before = hook_api_on_event_handler_before_cb,
 959         .hook_api_on_event_handler_after = hook_api_on_event_handler_after_cb,
 960         .hook_api_settings = hook_api_settings_cb,
 961 };
 962
 963 /******************************************************************************
 964  * section: hooks for tracing daemon interface (export)
 965  *****************************************************************************/
 966
 967 #define _HOOK_API_2_(flag,func,...)   \
 968         struct afb_hook_api *hook; \
 969         struct afb_hookid hookid; \
 970         const char *apiname = afb_export_apiname(export); \
 971         pthread_rwlock_rdlock(&rwlock); \
 972         init_hookid(&hookid); \
 973         hook = list_of_api_hooks; \
 974         while (hook) { \
 975                 if (hook->refcount \
 976                  && hook->itf->hook_api_##func \
 977                  && (hook->flags & afb_hook_flag_api_##flag) != 0 \
 978                  && MATCH_API(hook->api, apiname)) { \
 979                         hook->itf->hook_api_##func(hook->closure, &hookid, __VA_ARGS__); \
 980                 } \
 981                 hook = hook->next; \
 982         } \
 983         pthread_rwlock_unlock(&rwlock);
 984
 985 #define _HOOK_API_(what,...)   _HOOK_API_2_(what,what,__VA_ARGS__)
 986
 987 void afb_hook_api_event_broadcast_before(const struct afb_export *export, const char *name, struct json_object *object)
 988 {
 989         _HOOK_API_2_(event_broadcast, event_broadcast_before, export, name, object);
 990 }
 991
 992 int afb_hook_api_event_broadcast_after(const struct afb_export *export, const char *name, struct json_object *object, int result)
 993 {
 994         _HOOK_API_2_(event_broadcast, event_broadcast_after, export, name, object, result);
 995         return result;
 996 }
 997
 998 struct sd_event *afb_hook_api_get_event_loop(const struct afb_export *export, struct sd_event *result)
 999 {
1000         _HOOK_API_(get_event_loop, export, result);
1001         return result;
1002 }
1003
1004 struct sd_bus *afb_hook_api_get_user_bus(const struct afb_export *export, struct sd_bus *result)
1005 {
1006         _HOOK_API_(get_user_bus, export, result);
1007         return result;
1008 }
1009
1010 struct sd_bus *afb_hook_api_get_system_bus(const struct afb_export *export, struct sd_bus *result)
1011 {
1012         _HOOK_API_(get_system_bus, export, result);
1013         return result;
1014 }
1015
1016 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)
1017 {
1018         _HOOK_API_(vverbose, export, level, file, line, function, fmt, args);
1019 }
1020
1021 struct afb_event_x2 *afb_hook_api_event_make(const struct afb_export *export, const char *name, struct afb_event_x2 *result)
1022 {
1023         _HOOK_API_(event_make, export, name, result);
1024         return result;
1025 }
1026
1027 int afb_hook_api_rootdir_get_fd(const struct afb_export *export, int result)
1028 {
1029         _HOOK_API_(rootdir_get_fd, export, result);
1030         return result;
1031 }
1032
1033 int afb_hook_api_rootdir_open_locale(const struct afb_export *export, const char *filename, int flags, const char *locale, int result)
1034 {
1035         _HOOK_API_(rootdir_open_locale, export, filename, flags, locale, result);
1036         return result;
1037 }
1038
1039 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)
1040 {
1041         _HOOK_API_(queue_job, export, callback, argument, group, timeout, result);
1042         return result;
1043 }
1044
1045 void afb_hook_api_legacy_unstore_req(const struct afb_export *export, struct afb_stored_req *sreq)
1046 {
1047         _HOOK_API_(legacy_unstore_req, export, sreq);
1048 }
1049
1050 void afb_hook_api_require_api(const struct afb_export *export, const char *name, int initialized)
1051 {
1052         _HOOK_API_(require_api, export, name, initialized);
1053 }
1054
1055 int afb_hook_api_require_api_result(const struct afb_export *export, const char *name, int initialized, int result)
1056 {
1057         _HOOK_API_2_(require_api, require_api_result, export, name, initialized, result);
1058         return result;
1059 }
1060
1061 int afb_hook_api_add_alias(const struct afb_export *export, const char *api, const char *alias, int result)
1062 {
1063         _HOOK_API_(add_alias, export, api, alias, result);
1064         return result;
1065 }
1066
1067 void afb_hook_api_start_before(const struct afb_export *export)
1068 {
1069         _HOOK_API_2_(start, start_before, export);
1070 }
1071
1072 int afb_hook_api_start_after(const struct afb_export *export, int status)
1073 {
1074         _HOOK_API_2_(start, start_after, export, status);
1075         return status;
1076 }
1077
1078 void afb_hook_api_on_event_before(const struct afb_export *export, const char *event, int event_x2, struct json_object *object)
1079 {
1080         _HOOK_API_2_(on_event, on_event_before, export, event, event_x2, object);
1081 }
1082
1083 void afb_hook_api_on_event_after(const struct afb_export *export, const char *event, int event_x2, struct json_object *object)
1084 {
1085         _HOOK_API_2_(on_event, on_event_after, export, event, event_x2, object);
1086 }
1087
1088 void afb_hook_api_call(const struct afb_export *export, const char *api, const char *verb, struct json_object *args)
1089 {
1090         _HOOK_API_(call, export, api, verb, args);
1091 }
1092
1093 void afb_hook_api_call_result(const struct afb_export *export, struct json_object *object, const char*error, const char *info)
1094 {
1095         _HOOK_API_2_(call, call_result, export, object, error, info);
1096
1097 }
1098
1099 void afb_hook_api_callsync(const struct afb_export *export, const char *api, const char *verb, struct json_object *args)
1100 {
1101         _HOOK_API_(callsync, export, api, verb, args);
1102 }
1103
1104 int afb_hook_api_callsync_result(const struct afb_export *export, int status, struct json_object *object, const char *error, const char *info)
1105 {
1106         _HOOK_API_2_(callsync, callsync_result, export, status, object, error, info);
1107         return status;
1108 }
1109
1110 void afb_hook_api_new_api_before(const struct afb_export *export, const char *api, const char *info, int noconcurrency)
1111 {
1112         _HOOK_API_2_(new_api, new_api_before, export, api, info, noconcurrency);
1113 }
1114
1115 int afb_hook_api_new_api_after(const struct afb_export *export, int result, const char *api)
1116 {
1117         _HOOK_API_2_(new_api, new_api_after, export, result, api);
1118         return result;
1119 }
1120
1121 int afb_hook_api_api_set_verbs_v2(const struct afb_export *export, int result, const struct afb_verb_v2 *verbs)
1122 {
1123         _HOOK_API_2_(api_set_verbs, api_set_verbs_v2, export, result, verbs);
1124         return result;
1125 }
1126
1127 int afb_hook_api_api_set_verbs_v3(const struct afb_export *export, int result, const struct afb_verb_v3 *verbs)
1128 {
1129         _HOOK_API_2_(api_set_verbs, api_set_verbs_v3, export, result, verbs);
1130         return result;
1131 }
1132
1133 int afb_hook_api_api_add_verb(const struct afb_export *export, int result, const char *verb, const char *info, int glob)
1134 {
1135         _HOOK_API_(api_add_verb, export, result, verb, info, glob);
1136         return result;
1137 }
1138
1139 int afb_hook_api_api_del_verb(const struct afb_export *export, int result, const char *verb)
1140 {
1141         _HOOK_API_(api_del_verb, export, result, verb);
1142         return result;
1143 }
1144
1145 int afb_hook_api_api_set_on_event(const struct afb_export *export, int result)
1146 {
1147         _HOOK_API_(api_set_on_event, export, result);
1148         return result;
1149 }
1150
1151 int afb_hook_api_api_set_on_init(const struct afb_export *export, int result)
1152 {
1153         _HOOK_API_(api_set_on_init, export, result);
1154         return result;
1155 }
1156
1157 void afb_hook_api_api_seal(const struct afb_export *export)
1158 {
1159         _HOOK_API_(api_seal, export);
1160 }
1161
1162 int afb_hook_api_event_handler_add(const struct afb_export *export, int result, const char *pattern)
1163 {
1164         _HOOK_API_(event_handler_add, export, result, pattern);
1165         return result;
1166 }
1167 int afb_hook_api_event_handler_del(const struct afb_export *export, int result, const char *pattern)
1168 {
1169         _HOOK_API_(event_handler_del, export, result, pattern);
1170         return result;
1171 }
1172 int afb_hook_api_class_provide(const struct afb_export *export, int result, const char *name)
1173 {
1174         _HOOK_API_(class_provide, export, result, name);
1175         return result;
1176 }
1177 int afb_hook_api_class_require(const struct afb_export *export, int result, const char *name)
1178 {
1179         _HOOK_API_(class_require, export, result, name);
1180         return result;
1181 }
1182
1183 int afb_hook_api_delete_api(const struct afb_export *export, int result)
1184 {
1185         _HOOK_API_(delete_api, export, result);
1186         return result;
1187 }
1188
1189 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)
1190 {
1191         _HOOK_API_2_(on_event_handler, on_event_handler_before, export, event, event_x2, object, pattern);
1192 }
1193
1194 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)
1195 {
1196         _HOOK_API_2_(on_event_handler, on_event_handler_after, export, event, event_x2, object, pattern);
1197 }
1198
1199 struct json_object *afb_hook_api_settings(const struct afb_export *export, struct json_object *object)
1200 {
1201         _HOOK_API_(settings, export, object);
1202         return object;
1203 }
1204
1205 /******************************************************************************
1206  * section: hooking export
1207  *****************************************************************************/
1208
1209 int afb_hook_flags_api(const char *api)
1210 {
1211         int flags;
1212         struct afb_hook_api *hook;
1213
1214         flags = 0;
1215         pthread_rwlock_rdlock(&rwlock);
1216         hook = list_of_api_hooks;
1217         while (hook) {
1218                 if (!api || MATCH_API(hook->api, api))
1219                         flags |= hook->flags;
1220                 hook = hook->next;
1221         }
1222         pthread_rwlock_unlock(&rwlock);
1223         return flags;
1224 }
1225
1226 struct afb_hook_api *afb_hook_create_api(const char *api, int flags, struct afb_hook_api_itf *itf, void *closure)
1227 {
1228         struct afb_hook_api *hook;
1229
1230         /* alloc the result */
1231         hook = calloc(1, sizeof *hook);
1232         if (hook == NULL)
1233                 return NULL;
1234
1235         /* get a copy of the names */
1236         hook->api = api ? strdup(api) : NULL;
1237         if (api && !hook->api) {
1238                 free(hook);
1239                 return NULL;
1240         }
1241
1242         /* initialise the rest */
1243         hook->refcount = 1;
1244         hook->flags = flags;
1245         hook->itf = itf ? itf : &hook_api_default_itf;
1246         hook->closure = closure;
1247
1248         /* record the hook */
1249         pthread_mutex_lock(&mutex);
1250         hook->next = list_of_api_hooks;
1251         list_of_api_hooks = hook;
1252         pthread_mutex_unlock(&mutex);
1253
1254         /* returns it */
1255         return hook;
1256 }
1257
1258 struct afb_hook_api *afb_hook_addref_api(struct afb_hook_api *hook)
1259 {
1260         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1261         return hook;
1262 }
1263
1264 static void hook_clean_api()
1265 {
1266         struct afb_hook_api **prv, *hook, *head;
1267
1268         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1269                 /* unlink under mutex */
1270                 head = NULL;
1271                 pthread_mutex_lock(&mutex);
1272                 prv = &list_of_api_hooks;
1273                 while ((hook = *prv)) {
1274                         if (hook->refcount)
1275                                 prv = &(*prv)->next;
1276                         else {
1277                                 *prv = hook->next;
1278                                 hook->next = head;
1279                                 head = hook;
1280                         }
1281                 }
1282                 pthread_mutex_unlock(&mutex);
1283                 pthread_rwlock_unlock(&rwlock);
1284
1285                 /* free found hooks */
1286                 while((hook = head)) {
1287                         head = hook->next;
1288                         free(hook->api);
1289                         free(hook);
1290                 }
1291         }
1292 }
1293
1294 void afb_hook_unref_api(struct afb_hook_api *hook)
1295 {
1296         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
1297                 hook_clean_api();
1298 }
1299
1300 /******************************************************************************
1301  * section: default callbacks for tracing service interface (evt)
1302  *****************************************************************************/
1303
1304 static void _hook_evt_(const char *evt, int id, const char *format, ...)
1305 {
1306         va_list ap;
1307         va_start(ap, format);
1308         _hook_("evt-%s:%d", format, ap, evt, id);
1309         va_end(ap);
1310 }
1311
1312 static void hook_evt_create_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1313 {
1314         _hook_evt_(evt, id, "create");
1315 }
1316
1317 static void hook_evt_push_before_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj)
1318 {
1319         _hook_evt_(evt, id, "push.before(%s)", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE));
1320 }
1321
1322
1323 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)
1324 {
1325         _hook_evt_(evt, id, "push.after(%s) -> %d", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE), result);
1326 }
1327
1328 static void hook_evt_broadcast_before_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, struct json_object *obj)
1329 {
1330         _hook_evt_(evt, id, "broadcast.before(%s)", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE));
1331 }
1332
1333 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)
1334 {
1335         _hook_evt_(evt, id, "broadcast.after(%s) -> %d", json_object_to_json_string_ext(obj, JSON_C_TO_STRING_NOSLASHESCAPE), result);
1336 }
1337
1338 static void hook_evt_name_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id, const char *result)
1339 {
1340         _hook_evt_(evt, id, "name -> %s", result);
1341 }
1342
1343 static void hook_evt_addref_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1344 {
1345         _hook_evt_(evt, id, "addref");
1346 }
1347
1348 static void hook_evt_unref_cb(void *closure, const struct afb_hookid *hookid, const char *evt, int id)
1349 {
1350         _hook_evt_(evt, id, "unref");
1351 }
1352
1353 static struct afb_hook_evt_itf hook_evt_default_itf = {
1354         .hook_evt_create = hook_evt_create_cb,
1355         .hook_evt_push_before = hook_evt_push_before_cb,
1356         .hook_evt_push_after = hook_evt_push_after_cb,
1357         .hook_evt_broadcast_before = hook_evt_broadcast_before_cb,
1358         .hook_evt_broadcast_after = hook_evt_broadcast_after_cb,
1359         .hook_evt_name = hook_evt_name_cb,
1360         .hook_evt_addref = hook_evt_addref_cb,
1361         .hook_evt_unref = hook_evt_unref_cb
1362 };
1363
1364 /******************************************************************************
1365  * section: hooks for tracing events interface (evt)
1366  *****************************************************************************/
1367
1368 #define _HOOK_EVT_(what,...)   \
1369         struct afb_hook_evt *hook; \
1370         struct afb_hookid hookid; \
1371         pthread_rwlock_rdlock(&rwlock); \
1372         init_hookid(&hookid); \
1373         hook = list_of_evt_hooks; \
1374         while (hook) { \
1375                 if (hook->refcount \
1376                  && hook->itf->hook_evt_##what \
1377                  && (hook->flags & afb_hook_flag_evt_##what) != 0 \
1378                  && MATCH_EVENT(hook->pattern, evt)) { \
1379                         hook->itf->hook_evt_##what(hook->closure, &hookid, __VA_ARGS__); \
1380                 } \
1381                 hook = hook->next; \
1382         } \
1383         pthread_rwlock_unlock(&rwlock);
1384
1385 void afb_hook_evt_create(const char *evt, int id)
1386 {
1387         _HOOK_EVT_(create, evt, id);
1388 }
1389
1390 void afb_hook_evt_push_before(const char *evt, int id, struct json_object *obj)
1391 {
1392         _HOOK_EVT_(push_before, evt, id, obj);
1393 }
1394
1395 int afb_hook_evt_push_after(const char *evt, int id, struct json_object *obj, int result)
1396 {
1397         _HOOK_EVT_(push_after, evt, id, obj, result);
1398         return result;
1399 }
1400
1401 void afb_hook_evt_broadcast_before(const char *evt, int id, struct json_object *obj)
1402 {
1403         _HOOK_EVT_(broadcast_before, evt, id, obj);
1404 }
1405
1406 int afb_hook_evt_broadcast_after(const char *evt, int id, struct json_object *obj, int result)
1407 {
1408         _HOOK_EVT_(broadcast_after, evt, id, obj, result);
1409         return result;
1410 }
1411
1412 void afb_hook_evt_name(const char *evt, int id, const char *result)
1413 {
1414         _HOOK_EVT_(name, evt, id, result);
1415 }
1416
1417 void afb_hook_evt_addref(const char *evt, int id)
1418 {
1419         _HOOK_EVT_(addref, evt, id);
1420 }
1421
1422 void afb_hook_evt_unref(const char *evt, int id)
1423 {
1424         _HOOK_EVT_(unref, evt, id);
1425 }
1426
1427 /******************************************************************************
1428  * section: hooking services (evt)
1429  *****************************************************************************/
1430
1431 int afb_hook_flags_evt(const char *name)
1432 {
1433         int flags;
1434         struct afb_hook_evt *hook;
1435
1436         flags = 0;
1437         pthread_rwlock_rdlock(&rwlock);
1438         hook = list_of_evt_hooks;
1439         while (hook) {
1440                 if (!name || MATCH_EVENT(hook->pattern, name))
1441                         flags |= hook->flags;
1442                 hook = hook->next;
1443         }
1444         pthread_rwlock_unlock(&rwlock);
1445         return flags;
1446 }
1447
1448 struct afb_hook_evt *afb_hook_create_evt(const char *pattern, int flags, struct afb_hook_evt_itf *itf, void *closure)
1449 {
1450         struct afb_hook_evt *hook;
1451
1452         /* alloc the result */
1453         hook = calloc(1, sizeof *hook);
1454         if (hook == NULL)
1455                 return NULL;
1456
1457         /* get a copy of the names */
1458         hook->pattern = pattern ? strdup(pattern) : NULL;
1459         if (pattern && !hook->pattern) {
1460                 free(hook);
1461                 return NULL;
1462         }
1463
1464         /* initialise the rest */
1465         hook->refcount = 1;
1466         hook->flags = flags;
1467         hook->itf = itf ? itf : &hook_evt_default_itf;
1468         hook->closure = closure;
1469
1470         /* record the hook */
1471         pthread_mutex_lock(&mutex);
1472         hook->next = list_of_evt_hooks;
1473         list_of_evt_hooks = hook;
1474         pthread_mutex_unlock(&mutex);
1475
1476         /* returns it */
1477         return hook;
1478 }
1479
1480 struct afb_hook_evt *afb_hook_addref_evt(struct afb_hook_evt *hook)
1481 {
1482         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1483         return hook;
1484 }
1485
1486 static void hook_clean_evt()
1487 {
1488         struct afb_hook_evt **prv, *hook, *head;
1489
1490         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1491                 /* unlink under mutex */
1492                 head = NULL;
1493                 pthread_mutex_lock(&mutex);
1494                 prv = &list_of_evt_hooks;
1495                 while ((hook = *prv)) {
1496                         if (hook->refcount)
1497                                 prv = &(*prv)->next;
1498                         else {
1499                                 *prv = hook->next;
1500                                 hook->next = head;
1501                                 head = hook;
1502                         }
1503                 }
1504                 pthread_mutex_unlock(&mutex);
1505                 pthread_rwlock_unlock(&rwlock);
1506
1507                 /* free found hooks */
1508                 while((hook = head)) {
1509                         head = hook->next;
1510                         free(hook->pattern);
1511                         free(hook);
1512                 }
1513         }
1514 }
1515
1516 void afb_hook_unref_evt(struct afb_hook_evt *hook)
1517 {
1518         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
1519                 hook_clean_evt();
1520 }
1521
1522 /******************************************************************************
1523  * section: default callbacks for sessions (session)
1524  *****************************************************************************/
1525
1526 static void _hook_session_(struct afb_session *session, const char *format, ...)
1527 {
1528         va_list ap;
1529         va_start(ap, format);
1530         _hook_("session-%s", format, ap, afb_session_uuid(session));
1531         va_end(ap);
1532 }
1533
1534 static void hook_session_create_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1535 {
1536         _hook_session_(session, "create");
1537 }
1538
1539 static void hook_session_close_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1540 {
1541         _hook_session_(session, "close");
1542 }
1543
1544 static void hook_session_destroy_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1545 {
1546         _hook_session_(session, "destroy");
1547 }
1548
1549 static void hook_session_addref_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1550 {
1551         _hook_session_(session, "addref");
1552 }
1553
1554 static void hook_session_unref_cb(void *closure, const struct afb_hookid *hookid, struct afb_session *session)
1555 {
1556         _hook_session_(session, "unref");
1557 }
1558
1559 static struct afb_hook_session_itf hook_session_default_itf = {
1560         .hook_session_create = hook_session_create_cb,
1561         .hook_session_close = hook_session_close_cb,
1562         .hook_session_destroy = hook_session_destroy_cb,
1563         .hook_session_addref = hook_session_addref_cb,
1564         .hook_session_unref = hook_session_unref_cb
1565 };
1566
1567 /******************************************************************************
1568  * section: hooks for tracing sessions (session)
1569  *****************************************************************************/
1570
1571 #define _HOOK_SESSION_(what,...)   \
1572         struct afb_hook_session *hook; \
1573         struct afb_hookid hookid; \
1574         const char *sessid = 0; \
1575         pthread_rwlock_rdlock(&rwlock); \
1576         init_hookid(&hookid); \
1577         hook = list_of_session_hooks; \
1578         while (hook) { \
1579                 if (hook->refcount \
1580                  && hook->itf->hook_session_##what \
1581                  && (hook->flags & afb_hook_flag_session_##what) != 0 \
1582                  && MATCH_SESSION(hook->pattern, (sessid?:(sessid=afb_session_uuid(session))))) { \
1583                         hook->itf->hook_session_##what(hook->closure, &hookid, __VA_ARGS__); \
1584                 } \
1585                 hook = hook->next; \
1586         } \
1587         pthread_rwlock_unlock(&rwlock);
1588
1589 void afb_hook_session_create(struct afb_session *session)
1590 {
1591         _HOOK_SESSION_(create, session);
1592 }
1593
1594 void afb_hook_session_close(struct afb_session *session)
1595 {
1596         _HOOK_SESSION_(close, session);
1597 }
1598
1599 void afb_hook_session_destroy(struct afb_session *session)
1600 {
1601         _HOOK_SESSION_(destroy, session);
1602 }
1603
1604 void afb_hook_session_addref(struct afb_session *session)
1605 {
1606         _HOOK_SESSION_(addref, session);
1607 }
1608
1609 void afb_hook_session_unref(struct afb_session *session)
1610 {
1611         _HOOK_SESSION_(unref, session);
1612 }
1613
1614
1615 /******************************************************************************
1616  * section: hooking sessions (session)
1617  *****************************************************************************/
1618
1619 struct afb_hook_session *afb_hook_create_session(const char *pattern, int flags, struct afb_hook_session_itf *itf, void *closure)
1620 {
1621         struct afb_hook_session *hook;
1622
1623         /* alloc the result */
1624         hook = calloc(1, sizeof *hook);
1625         if (hook == NULL)
1626                 return NULL;
1627
1628         /* get a copy of the names */
1629         hook->pattern = pattern ? strdup(pattern) : NULL;
1630         if (pattern && !hook->pattern) {
1631                 free(hook);
1632                 return NULL;
1633         }
1634
1635         /* initialise the rest */
1636         hook->refcount = 1;
1637         hook->flags = flags;
1638         hook->itf = itf ? itf : &hook_session_default_itf;
1639         hook->closure = closure;
1640
1641         /* record the hook */
1642         pthread_mutex_lock(&mutex);
1643         hook->next = list_of_session_hooks;
1644         list_of_session_hooks = hook;
1645         pthread_mutex_unlock(&mutex);
1646
1647         /* returns it */
1648         return hook;
1649 }
1650
1651 struct afb_hook_session *afb_hook_addref_session(struct afb_hook_session *hook)
1652 {
1653         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1654         return hook;
1655 }
1656
1657 static void hook_clean_session()
1658 {
1659         struct afb_hook_session **prv, *hook, *head;
1660
1661         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1662                 /* unlink under mutex */
1663                 head = NULL;
1664                 pthread_mutex_lock(&mutex);
1665                 prv = &list_of_session_hooks;
1666                 while ((hook = *prv)) {
1667                         if (hook->refcount)
1668                                 prv = &(*prv)->next;
1669                         else {
1670                                 *prv = hook->next;
1671                                 hook->next = head;
1672                                 head = hook;
1673                         }
1674                 }
1675                 pthread_mutex_unlock(&mutex);
1676                 pthread_rwlock_unlock(&rwlock);
1677
1678                 /* free found hooks */
1679                 while((hook = head)) {
1680                         head = hook->next;
1681                         free(hook->pattern);
1682                         free(hook);
1683                 }
1684         }
1685 }
1686
1687 void afb_hook_unref_session(struct afb_hook_session *hook)
1688 {
1689         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED))
1690                 hook_clean_session();
1691 }
1692
1693 /******************************************************************************
1694  * section: default callbacks for globals (global)
1695  *****************************************************************************/
1696
1697 static void _hook_global_(const char *format, ...)
1698 {
1699         va_list ap;
1700         va_start(ap, format);
1701         _hook_("global", format, ap);
1702         va_end(ap);
1703 }
1704
1705 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)
1706 {
1707         int len;
1708         char *msg;
1709         va_list ap;
1710
1711         va_copy(ap, args);
1712         len = vasprintf(&msg, fmt, ap);
1713         va_end(ap);
1714
1715         if (len < 0)
1716                 _hook_global_("vverbose(%d:%s, %s, %d, %s) -> %s ? ? ?", level, verbose_name_of_level(level), file, line, func, fmt);
1717         else {
1718                 _hook_global_("vverbose(%d:%s, %s, %d, %s) -> %s", level, verbose_name_of_level(level), file, line, func, msg);
1719                 free(msg);
1720         }
1721 }
1722
1723 static struct afb_hook_global_itf hook_global_default_itf = {
1724         .hook_global_vverbose = hook_global_vverbose_cb
1725 };
1726
1727 /******************************************************************************
1728  * section: hooks for tracing globals (global)
1729  *****************************************************************************/
1730
1731 #define _HOOK_GLOBAL_(what,...)   \
1732         struct afb_hook_global *hook; \
1733         struct afb_hookid hookid; \
1734         pthread_rwlock_rdlock(&rwlock); \
1735         init_hookid(&hookid); \
1736         hook = list_of_global_hooks; \
1737         while (hook) { \
1738                 if (hook->refcount \
1739                  && hook->itf->hook_global_##what \
1740                  && (hook->flags & afb_hook_flag_global_##what) != 0) { \
1741                         hook->itf->hook_global_##what(hook->closure, &hookid, __VA_ARGS__); \
1742                 } \
1743                 hook = hook->next; \
1744         } \
1745         pthread_rwlock_unlock(&rwlock);
1746
1747 static void afb_hook_global_vverbose(int level, const char *file, int line, const char *func, const char *fmt, va_list args)
1748 {
1749         _HOOK_GLOBAL_(vverbose, level, file ?: "?", line, func ?: "?", fmt ?: "", args);
1750 }
1751
1752 /******************************************************************************
1753  * section: hooking globals (global)
1754  *****************************************************************************/
1755
1756 static void update_global()
1757 {
1758         struct afb_hook_global *hook;
1759         int flags = 0;
1760
1761         pthread_rwlock_rdlock(&rwlock);
1762         hook = list_of_global_hooks;
1763         while (hook) {
1764                 if (hook->refcount)
1765                         flags = hook->flags;
1766                 hook = hook->next;
1767         }
1768         verbose_observer = (flags & afb_hook_flag_global_vverbose) ? afb_hook_global_vverbose : NULL;
1769         pthread_rwlock_unlock(&rwlock);
1770 }
1771
1772 struct afb_hook_global *afb_hook_create_global(int flags, struct afb_hook_global_itf *itf, void *closure)
1773 {
1774         struct afb_hook_global *hook;
1775
1776         /* alloc the result */
1777         hook = calloc(1, sizeof *hook);
1778         if (hook == NULL)
1779                 return NULL;
1780
1781         /* initialise the rest */
1782         hook->refcount = 1;
1783         hook->flags = flags;
1784         hook->itf = itf ? itf : &hook_global_default_itf;
1785         hook->closure = closure;
1786
1787         /* record the hook */
1788         pthread_mutex_lock(&mutex);
1789         hook->next = list_of_global_hooks;
1790         list_of_global_hooks = hook;
1791         pthread_mutex_unlock(&mutex);
1792
1793         /* update hooking */
1794         update_global();
1795
1796         /* returns it */
1797         return hook;
1798 }
1799
1800 struct afb_hook_global *afb_hook_addref_global(struct afb_hook_global *hook)
1801 {
1802         __atomic_add_fetch(&hook->refcount, 1, __ATOMIC_RELAXED);
1803         return hook;
1804 }
1805
1806 static void hook_clean_global()
1807 {
1808         struct afb_hook_global **prv, *hook, *head;
1809
1810         if (pthread_rwlock_trywrlock(&rwlock) == 0) {
1811                 /* unlink under mutex */
1812                 head = NULL;
1813                 pthread_mutex_lock(&mutex);
1814                 prv = &list_of_global_hooks;
1815                 while ((hook = *prv)) {
1816                         if (hook->refcount)
1817                                 prv = &(*prv)->next;
1818                         else {
1819                                 *prv = hook->next;
1820                                 hook->next = head;
1821                                 head = hook;
1822                         }
1823                 }
1824                 pthread_mutex_unlock(&mutex);
1825                 pthread_rwlock_unlock(&rwlock);
1826
1827                 /* free found hooks */
1828                 while((hook = head)) {
1829                         head = hook->next;
1830                         free(hook);
1831                 }
1832         }
1833 }
1834
1835 void afb_hook_unref_global(struct afb_hook_global *hook)
1836 {
1837         if (hook && !__atomic_sub_fetch(&hook->refcount, 1, __ATOMIC_RELAXED)) {
1838                 /* update hooking */
1839                 update_global();
1840                 hook_clean_global();
1841         }
1842 }
1843
1844 #endif /* WITH_AFB_HOOK *******************************************************/