| // Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| #ifndef PLATFORM_SIGNAL_BLOCKER_H_ |
| #define PLATFORM_SIGNAL_BLOCKER_H_ |
| |
| #include "platform/globals.h" |
| #include "platform/assert.h" |
| |
| #if defined(TARGET_OS_WINDOWS) |
| #error Do not include this file on Windows. |
| #endif |
| |
| #include <pthread.h> |
| #include <signal.h> // NOLINT |
| |
| namespace dart { |
| |
| class ThreadSignalBlocker { |
| public: |
| explicit ThreadSignalBlocker(int sig) { |
| sigset_t signal_mask; |
| sigemptyset(&signal_mask); |
| sigaddset(&signal_mask, sig); |
| // Add sig to signal mask. |
| int r = pthread_sigmask(SIG_BLOCK, &signal_mask, &old); |
| USE(r); |
| ASSERT(r == 0); |
| } |
| |
| ThreadSignalBlocker(int sigs_count, const int sigs[]) { |
| sigset_t signal_mask; |
| sigemptyset(&signal_mask); |
| for (int i = 0; i < sigs_count; i++) { |
| sigaddset(&signal_mask, sigs[i]); |
| } |
| // Add sig to signal mask. |
| int r = pthread_sigmask(SIG_BLOCK, &signal_mask, &old); |
| USE(r); |
| ASSERT(r == 0); |
| } |
| |
| ~ThreadSignalBlocker() { |
| // Restore signal mask. |
| int r = pthread_sigmask(SIG_SETMASK, &old, NULL); |
| USE(r); |
| ASSERT(r == 0); |
| } |
| |
| private: |
| sigset_t old; |
| }; |
| |
| |
| // The definition below is copied from Linux and adapted to avoid lint |
| // errors (type long int changed to intptr_t and do/while split on |
| // separate lines with body in {}s) and to also block signals. |
| #define TEMP_FAILURE_RETRY(expression) \ |
| ({ ThreadSignalBlocker tsb(SIGPROF); \ |
| intptr_t __result; \ |
| do { \ |
| __result = (expression); \ |
| } while ((__result == -1L) && (errno == EINTR)); \ |
| __result; }) |
| |
| // This is a version of TEMP_FAILURE_RETRY which does not use the value |
| // returned from the expression. |
| #define VOID_TEMP_FAILURE_RETRY(expression) \ |
| (static_cast<void>(TEMP_FAILURE_RETRY(expression))) |
| |
| // This macro can be used to insert checks that a call is made, that |
| // was expected to not return EINTR, but did it anyway. |
| #define NO_RETRY_EXPECTED(expression) \ |
| ({ intptr_t __result = (expression); \ |
| if (__result == -1L && errno == EINTR) { \ |
| FATAL("Unexpected EINTR errno"); \ |
| } \ |
| __result; }) |
| |
| #define VOID_NO_RETRY_EXPECTED(expression) \ |
| (static_cast<void>(NO_RETRY_EXPECTED(expression))) |
| |
| // Define to check in debug mode, if a signal is currently being blocked. |
| #define CHECK_IS_BLOCKING(signal) \ |
| ({ sigset_t signal_mask; \ |
| int __r = pthread_sigmask(SIG_BLOCK, NULL, &signal_mask); \ |
| USE(__r); \ |
| ASSERT(__r == 0); \ |
| sigismember(&signal_mask, signal); }) \ |
| |
| |
| // Versions of the above, that does not enter a signal blocking scope. Use only |
| // when a signal blocking scope is entered manually. |
| #define TEMP_FAILURE_RETRY_NO_SIGNAL_BLOCKER(expression) \ |
| ({ intptr_t __result; \ |
| ASSERT(CHECK_IS_BLOCKING(SIGPROF)); \ |
| do { \ |
| __result = (expression); \ |
| } while ((__result == -1L) && (errno == EINTR)); \ |
| __result; }) |
| |
| #define VOID_TEMP_FAILURE_RETRY_NO_SIGNAL_BLOCKER(expression) \ |
| (static_cast<void>(TEMP_FAILURE_RETRY_NO_SIGNAL_BLOCKER(expression))) |
| |
| } // namespace dart |
| |
| #endif // PLATFORM_SIGNAL_BLOCKER_H_ |