src/common/linux/eintr_wrapper.h

// Copyright (c) 2010 Google Inc.
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//
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// modification, are permitted provided that the following conditions are
// met:
//
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#ifndef COMMON_LINUX_EINTR_WRAPPER_H_
#define COMMON_LINUX_EINTR_WRAPPER_H_

#include <errno.h>

// This provides a wrapper around system calls which may be interrupted by a
// signal and return EINTR. See man 7 signal.
//

#define HANDLE_EINTR(x) ({ \
  __typeof__(x) eintr_wrapper_result; \
  do { \
    eintr_wrapper_result = (x); \
  } while (eintr_wrapper_result == -1 && errno == EINTR); \
  eintr_wrapper_result; \
})

#define IGNORE_EINTR(x) ({ \
  __typeof__(x) eintr_wrapper_result; \
  do { \
    eintr_wrapper_result = (x); \
    if (eintr_wrapper_result == -1 && errno == EINTR) { \
      eintr_wrapper_result = 0; \
    } \
  } while (0); \
  eintr_wrapper_result; \
})

#endif  // COMMON_LINUX_EINTR_WRAPPER_H_