selftests/powerpc: Add a routine for retrieving an AUXV entry

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Michael Ellerman 2014-07-23 17:31:39 +10:00 committed by Benjamin Herrenschmidt
parent 985ac68eba
commit bd8bbd87f1
2 changed files with 49 additions and 0 deletions

View file

@ -5,10 +5,15 @@
#define _GNU_SOURCE /* For CPU_ZERO etc. */
#include <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <link.h>
#include <sched.h>
#include <setjmp.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "utils.h"
@ -250,3 +255,46 @@ bool require_paranoia_below(int level)
out:
return rc;
}
static char auxv[4096];
void *get_auxv_entry(int type)
{
ElfW(auxv_t) *p;
void *result;
ssize_t num;
int fd;
fd = open("/proc/self/auxv", O_RDONLY);
if (fd == -1) {
perror("open");
return NULL;
}
result = NULL;
num = read(fd, auxv, sizeof(auxv));
if (num < 0) {
perror("read");
goto out;
}
if (num > sizeof(auxv)) {
printf("Overflowed auxv buffer\n");
goto out;
}
p = (ElfW(auxv_t) *)auxv;
while (p->a_type != AT_NULL) {
if (p->a_type == type) {
result = (void *)p->a_un.a_val;
break;
}
p++;
}
out:
close(fd);
return result;
}

View file

@ -29,6 +29,7 @@ extern int notify_parent(union pipe write_pipe);
extern int notify_parent_of_error(union pipe write_pipe);
extern pid_t eat_cpu(int (test_function)(void));
extern bool require_paranoia_below(int level);
extern void *get_auxv_entry(int type);
struct addr_range {
uint64_t first, last;