| /* Implementation of the getrandom system call. |
| Copyright (C) 2016-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <sys/random.h> |
| #include <errno.h> |
| #include <unistd.h> |
| #include <sysdep-cancel.h> |
| |
| #ifdef __NR_getrandom |
| /* Write up to LENGTH bytes of randomness starting at BUFFER. |
| Return the number of bytes written, or -1 on error. */ |
| ssize_t |
| getrandom (void *buffer, size_t length, unsigned int flags) |
| { |
| return SYSCALL_CANCEL (getrandom, buffer, length, flags); |
| } |
| #else |
| /* Always provide a definition, even if the kernel headers lack the |
| system call number. */ |
| ssize_t |
| getrandom (void *buffer, size_t length, unsigned int flags) |
| { |
| /* Ideally, we would add a cancellation point here, but we currently |
| cannot do so inside libc. */ |
| __set_errno (ENOSYS); |
| return -1; |
| } |
| #endif |
