passt/arch.c
David Gibson 30b4f88167 arch: Avoid explicit access to 'environ'
We pass 'environ' to execve() in arch_avc2_exec(), so that we retain the
environment in the current process.  But the declaration of 'environ' is
a bit weird - it doesn't seem to be in a standard header, requiring a
manual explicit declaration.  But, we can avoid needing to reference it
explicitly by using execv() instead of execve().  This removes a clang
warning.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-11-07 12:46:29 +01:00

54 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* PASST - Plug A Simple Socket Transport
* for qemu/UNIX domain socket mode
*
* PASTA - Pack A Subtle Tap Abstraction
* for network namespace/tap device mode
*
* arch.c - Architecture-specific implementations
*
* Copyright (c) 2022 Red Hat GmbH
* Author: Stefano Brivio <sbrivio@redhat.com>
*/
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "log.h"
#include "util.h"
/**
* arch_avx2_exec() - Switch to AVX2 build if supported
* @argv: Arguments from command line
*/
#ifdef __x86_64__
void arch_avx2_exec(char **argv)
{
char exe[PATH_MAX] = { 0 };
const char *p;
if (readlink("/proc/self/exe", exe, PATH_MAX - 1) < 0)
die_perror("Failed to read own /proc/self/exe link");
p = strstr(exe, ".avx2");
if (p && strlen(p) == strlen(".avx2"))
return;
if (__builtin_cpu_supports("avx2")) {
char new_path[PATH_MAX + sizeof(".avx2")];
if (snprintf_check(new_path, PATH_MAX + sizeof(".avx2"),
"%s.avx2", exe))
die_perror("Can't build AVX2 executable path");
execv(new_path, argv);
warn_perror("Can't run AVX2 build, using non-AVX2 version");
}
}
#else
void arch_avx2_exec(char **argv) { (void)argv; }
#endif