libc/src/sys/random/linux/getrandom.cpp

   1 //===-- Linux implementation of getrandom ---------------------------------===//
   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/sys/random/getrandom.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 LIBC_NAMESPACE {
  18
  19 LLVM_LIBC_FUNCTION(ssize_t, getrandom,
  20                    (void *buf, size_t buflen, unsigned int flags)) {
  21   ssize_t ret =
  22       LIBC_NAMESPACE::syscall_impl<ssize_t>(SYS_getrandom, buf, buflen, flags);
  23   if (ret < 0) {
  24     libc_errno = static_cast<int>(-ret);
  25     return -1;
  26   }
  27   return ret;
  28 }
  29
  30 } // namespace LIBC_NAMESPACE