mirror of https://github.com/aria2/aria2
98 lines
3.0 KiB
C
98 lines
3.0 KiB
C
/* <!-- copyright */
|
|
/*
|
|
* aria2 - The high speed download utility
|
|
*
|
|
* Copyright (C) 2014 Nils Maier
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*
|
|
* In addition, as a special exception, the copyright holders give
|
|
* permission to link the code of portions of this program with the
|
|
* OpenSSL library under certain conditions as described in each
|
|
* individual source file, and distribute linked combinations
|
|
* including the two.
|
|
* You must obey the GNU General Public License in all respects
|
|
* for all of the code used other than OpenSSL. If you modify
|
|
* file(s) with this exception, you may extend this exception to your
|
|
* version of the file(s), but you are not obligated to do so. If you
|
|
* do not wish to do so, delete this exception statement from your
|
|
* version. If you delete this exception statement from all source
|
|
* files in the program, then also delete it here.
|
|
*/
|
|
/* copyright --> */
|
|
|
|
#define _GNUSOURCE
|
|
#include <unistd.h>
|
|
#include <sys/syscall.h>
|
|
#include <linux/random.h>
|
|
#include <errno.h>
|
|
#include <linux/errno.h>
|
|
#include <stdint.h>
|
|
#include <stdio.h>
|
|
|
|
#include "config.h"
|
|
#include "getrandom_linux.h"
|
|
|
|
int getrandom_linux(void* buf, size_t buflen)
|
|
{
|
|
int rv = 0;
|
|
uint8_t* p = buf;
|
|
|
|
/* Loop while we did not fully retrieve what the user asked for.
|
|
* This may happen in particular when a call was EINTRupted.
|
|
*/
|
|
while (buflen) {
|
|
int read;
|
|
#ifdef HAVE_GETRANDOM
|
|
/* libc already has support */
|
|
read = getrandom(p, buflen, 0);
|
|
#else // HAVE_GETRANDOM
|
|
/* libc has no support, make the syscall ourselves */
|
|
read = syscall(SYS_getrandom, p, buflen, 0);
|
|
/* Some libc impl. might mess -ERESTART up */
|
|
if (read == -EINTR || read == -ERESTART) {
|
|
/* ERESTART, like EINTR, should restart the call, later, so handle both
|
|
* the same way.
|
|
*/
|
|
errno = EINTR;
|
|
read = -1;
|
|
}
|
|
/* Some other non-interrupted error happened, put error code into errno and
|
|
* switch read to -1 (return value).
|
|
*/
|
|
if (read < -1) {
|
|
errno = -read;
|
|
read = -1;
|
|
}
|
|
#endif // HAVE_GETRANDOM
|
|
if (read < 0) {
|
|
if (errno == EINTR) {
|
|
/* Restart call */
|
|
continue;
|
|
}
|
|
/* Call failed, return -1, errno should be set up correctly at this
|
|
* point.
|
|
*/
|
|
return -1;
|
|
}
|
|
/* We got some more randomness */
|
|
p += read;
|
|
rv += read;
|
|
buflen -= read;
|
|
}
|
|
|
|
return rv;
|
|
}
|