libc/src/unistd/linux/read.cpp

   1 //===-- Linux implementation of read --------------------------------------===//
   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/read.h"
  10
  11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
  12 #include "src/__support/common.h"
  13
  14 #include "src/errno/libc_errno.h"
  15 #include <sys/syscall.h> // For syscall numbers.
  16
  17 namespace __llvm_libc {
  18
  19 LLVM_LIBC_FUNCTION(ssize_t, read, (int fd, void *buf, size_t count)) {
  20   long ret = __llvm_libc::syscall_impl(SYS_read, fd, buf, count);
  21   if (ret < 0) {
  22     libc_errno = -ret;
  23     return -1;
  24   }
  25   return ret;
  26 }
  27
  28 } // namespace __llvm_libc