xref: /llvm-project/libc/src/sys/random/linux/getrandom.cpp (revision f0a3954ef1af274cb0b79a6e0bc51a31e0de540b)
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 __llvm_libc {
18 
19 LLVM_LIBC_FUNCTION(ssize_t, getrandom,
20                    (void *buf, size_t buflen, unsigned int flags)) {
21   ssize_t ret =
22       __llvm_libc::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 __llvm_libc
31