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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include "lint.h"
#include "thr_uberdata.h"
#include <libc.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/auxv.h>
#include <mtlib.h>
#include <thread.h>
#include <synch.h>
#include <atomic.h>
#include <limits.h>
static mutex_t auxlock = DEFAULTMUTEX;
/*
* Get auxiliary entry.
* Returns pointer to entry, or 0 if entry does not exist.
*/
static auxv_t *
_getaux(int type)
{
static auxv_t *auxb = NULL;
static size_t nauxv = 0;
ssize_t i;
/*
* The first time through, read the initial aux vector that was
* passed to the process at exec(2). Only do this once.
*/
if (auxb == NULL) {
lmutex_lock(&auxlock);
if (auxb == NULL) {
uberdata_t *udp = curthread->ul_uberdata;
struct stat statb;
auxv_t *buf = NULL;
char *path = "/proc/self/auxv";
char pbuf[PATH_MAX];
int fd;
if (udp->ub_broot != NULL) {
(void) snprintf(pbuf, sizeof (pbuf),
"%s/proc/self/auxv", udp->ub_broot);
path = pbuf;
}
if ((fd = open(path, O_RDONLY)) != -1 &&
fstat(fd, &statb) != -1)
buf = libc_malloc(
statb.st_size + sizeof (auxv_t));
if (buf != NULL) {
i = read(fd, buf, statb.st_size);
if (i != -1) {
nauxv = i / sizeof (auxv_t);
buf[nauxv].a_type = AT_NULL;
} else {
libc_free(buf);
buf = NULL;
}
}
if (fd != -1)
(void) close(fd);
membar_producer();
auxb = buf;
}
lmutex_unlock(&auxlock);
}
membar_consumer();
/*
* Scan the auxiliary entries looking for the required type.
*/
for (i = 0; i < nauxv; i++)
if (auxb[i].a_type == type)
return (&auxb[i]);
/*
* No auxiliary array (static executable) or entry not found.
*/
return ((auxv_t *)0);
}
/*
* These two routines are utilities exported to the rest of libc.
*/
long
___getauxval(int type)
{
auxv_t *auxp;
if ((auxp = _getaux(type)) != (auxv_t *)0)
return (auxp->a_un.a_val);
return (0);
}
void *
___getauxptr(int type)
{
auxv_t *auxp;
if ((auxp = _getaux(type)) != (auxv_t *)0)
return (auxp->a_un.a_ptr);
return (0);
}
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