Vitaly Buka | cbed206 | 2015-08-17 12:54:05 -0700 | [diff] [blame] | 1 | // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | // This provides a wrapper around system calls which may be interrupted by a |
| 6 | // signal and return EINTR. See man 7 signal. |
| 7 | // To prevent long-lasting loops (which would likely be a bug, such as a signal |
| 8 | // that should be masked) to go unnoticed, there is a limit after which the |
| 9 | // caller will nonetheless see an EINTR in Debug builds. |
| 10 | // |
| 11 | // On Windows, this wrapper macro does nothing. |
| 12 | // |
| 13 | // Don't wrap close calls in HANDLE_EINTR. Use IGNORE_EINTR if the return |
| 14 | // value of close is significant. See http://crbug.com/269623. |
| 15 | |
| 16 | #ifndef BASE_POSIX_EINTR_WRAPPER_H_ |
| 17 | #define BASE_POSIX_EINTR_WRAPPER_H_ |
| 18 | |
Vitaly Buka | 8750b27 | 2015-08-18 18:39:08 -0700 | [diff] [blame] | 19 | #include "base/build/build_config.h" |
Vitaly Buka | cbed206 | 2015-08-17 12:54:05 -0700 | [diff] [blame] | 20 | |
| 21 | #if defined(OS_POSIX) |
| 22 | |
| 23 | #include <errno.h> |
| 24 | |
| 25 | #if defined(NDEBUG) |
| 26 | |
| 27 | #define HANDLE_EINTR(x) ({ \ |
| 28 | decltype(x) eintr_wrapper_result; \ |
| 29 | do { \ |
| 30 | eintr_wrapper_result = (x); \ |
| 31 | } while (eintr_wrapper_result == -1 && errno == EINTR); \ |
| 32 | eintr_wrapper_result; \ |
| 33 | }) |
| 34 | |
| 35 | #else |
| 36 | |
| 37 | #define HANDLE_EINTR(x) ({ \ |
| 38 | int eintr_wrapper_counter = 0; \ |
| 39 | decltype(x) eintr_wrapper_result; \ |
| 40 | do { \ |
| 41 | eintr_wrapper_result = (x); \ |
| 42 | } while (eintr_wrapper_result == -1 && errno == EINTR && \ |
| 43 | eintr_wrapper_counter++ < 100); \ |
| 44 | eintr_wrapper_result; \ |
| 45 | }) |
| 46 | |
| 47 | #endif // NDEBUG |
| 48 | |
| 49 | #define IGNORE_EINTR(x) ({ \ |
| 50 | decltype(x) eintr_wrapper_result; \ |
| 51 | do { \ |
| 52 | eintr_wrapper_result = (x); \ |
| 53 | if (eintr_wrapper_result == -1 && errno == EINTR) { \ |
| 54 | eintr_wrapper_result = 0; \ |
| 55 | } \ |
| 56 | } while (0); \ |
| 57 | eintr_wrapper_result; \ |
| 58 | }) |
| 59 | |
| 60 | #else |
| 61 | |
| 62 | #define HANDLE_EINTR(x) (x) |
| 63 | #define IGNORE_EINTR(x) (x) |
| 64 | |
| 65 | #endif // OS_POSIX |
| 66 | |
| 67 | #endif // BASE_POSIX_EINTR_WRAPPER_H_ |