f6e0830298
So that we won't have an empty getauxval.o which is disliked by ranlib. Reported-by: Peter Maydell <peter.maydell@linaro.org> Tested-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
110 lines
3.0 KiB
C
110 lines
3.0 KiB
C
/*
|
|
* QEMU access to the auxiliary vector
|
|
*
|
|
* Copyright (C) 2013 Red Hat, Inc
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
|
|
#include "qemu-common.h"
|
|
#include "qemu/osdep.h"
|
|
|
|
#ifdef CONFIG_GETAUXVAL
|
|
/* Don't inline this in qemu/osdep.h, because pulling in <sys/auxv.h> for
|
|
the system declaration of getauxval pulls in the system <elf.h>, which
|
|
conflicts with qemu's version. */
|
|
|
|
#include <sys/auxv.h>
|
|
|
|
unsigned long qemu_getauxval(unsigned long key)
|
|
{
|
|
return getauxval(key);
|
|
}
|
|
#elif defined(__linux__)
|
|
#include "elf.h"
|
|
|
|
/* Our elf.h doesn't contain Elf32_auxv_t and Elf64_auxv_t, which is ok because
|
|
that just makes it easier to define it properly for the host here. */
|
|
typedef struct {
|
|
unsigned long a_type;
|
|
unsigned long a_val;
|
|
} ElfW_auxv_t;
|
|
|
|
static const ElfW_auxv_t *auxv;
|
|
|
|
static const ElfW_auxv_t *qemu_init_auxval(void)
|
|
{
|
|
ElfW_auxv_t *a;
|
|
ssize_t size = 512, r, ofs;
|
|
int fd;
|
|
|
|
/* Allocate some initial storage. Make sure the first entry is set
|
|
to end-of-list, so that we've got a valid list in case of error. */
|
|
auxv = a = g_malloc(size);
|
|
a[0].a_type = 0;
|
|
a[0].a_val = 0;
|
|
|
|
fd = open("/proc/self/auxv", O_RDONLY);
|
|
if (fd < 0) {
|
|
return a;
|
|
}
|
|
|
|
/* Read the first SIZE bytes. Hopefully, this covers everything. */
|
|
r = read(fd, a, size);
|
|
|
|
if (r == size) {
|
|
/* Continue to expand until we do get a partial read. */
|
|
do {
|
|
ofs = size;
|
|
size *= 2;
|
|
auxv = a = g_realloc(a, size);
|
|
r = read(fd, (char *)a + ofs, ofs);
|
|
} while (r == ofs);
|
|
}
|
|
|
|
close(fd);
|
|
return a;
|
|
}
|
|
|
|
unsigned long qemu_getauxval(unsigned long type)
|
|
{
|
|
const ElfW_auxv_t *a = auxv;
|
|
|
|
if (unlikely(a == NULL)) {
|
|
a = qemu_init_auxval();
|
|
}
|
|
|
|
for (; a->a_type != 0; a++) {
|
|
if (a->a_type == type) {
|
|
return a->a_val;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#else
|
|
|
|
unsigned long qemu_getauxval(unsigned long type)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#endif
|