hphp/util/sync-signal.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #pragma once
  18
  19 #include <cstdint>
  20 #include <pthread.h>
  21 #include <signal.h>
  22
  23 namespace HPHP {
  24
  25 using sighandler_sync_t = void(*)(int);
  26 using sigaction_sync_t = void(*)(int, siginfo_t*);
  27
  28 // Similar to signal(), but allows non-async-signal-safe functions to be used in
  29 // handlers. Return false upon failure.
  30 bool sync_signal(int signo, sighandler_sync_t h = nullptr);
  31
  32 // Synchronous signal handling for sigaction() style handlers.
  33 bool sync_signal_info(int signo, sigaction_sync_t h = nullptr);
  34
  35 // Block signals that we plan to handle synchronously, and start the thread to
  36 // process the signals.
  37 void block_sync_signals_and_start_handler_thread();
  38
  39 // Unblock sync signals and handle them using the default handlers, instead of
  40 // in the thread.
  41 void reset_sync_signals();
  42
  43 // Unblock sync signals and ignore them (instead of handing them with the
  44 // default hander).
  45 void ignore_sync_signals();
  46
  47 // Whether a signal is intended to be forwarded to PHP code.
  48 bool is_sync_signal(int signo);
  49
  50 // Restart the signal handler thread in the child process after fork.  Only used
  51 // when the child process will continue running HHVM, e.g., pcntl_fork().
  52 void postfork_restart_handler_thread();
  53
  54 }
  55