libc/src/unistd/linux/pipe.cpp

   1 //===-- Linux implementation of pipe --------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "src/unistd/pipe.h"
  10
  11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
  12 #include "src/__support/common.h"
  13 #include "src/__support/macros/config.h"
  14 #include "src/__support/macros/sanitizer.h" // for MSAN_UNPOISON
  15 #include "src/errno/libc_errno.h"
  16 #include <sys/syscall.h> // For syscall numbers.
  17
  18 namespace LIBC_NAMESPACE_DECL {
  19
  20 LLVM_LIBC_FUNCTION(int, pipe, (int pipefd[2])) {
  21 #ifdef SYS_pipe
  22   int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_pipe,
  23                                               reinterpret_cast<long>(pipefd));
  24 #elif defined(SYS_pipe2)
  25   int ret = LIBC_NAMESPACE::syscall_impl<int>(
  26       SYS_pipe2, reinterpret_cast<long>(pipefd), 0);
  27 #endif
  28   MSAN_UNPOISON(pipefd, sizeof(int) * 2);
  29   if (ret < 0) {
  30     libc_errno = -ret;
  31     return -1;
  32   }
  33   return ret;
  34 }
  35
  36 } // namespace LIBC_NAMESPACE_DECL