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/* Initialization code run first thing by the ELF startup code. Linux version.
Copyright (C) 1995-1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sysdep.h>
#include <fpu_control.h>
#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/types.h>
#include "kernel-features.h"
extern void __libc_init_secure (void);
extern void __libc_init (int, char **, char **);
extern void __libc_global_ctors (void);
/* The function is called from assembly stubs the compiler can't see. */
static void init (int, char **, char **) __attribute__ ((unused));
/* The function we use to get the kernel revision. */
extern int __sysctl (int *name, int nlen, void *oldval, size_t *oldlenp,
void *newval, size_t newlen);
extern int _dl_starting_up;
weak_extern (_dl_starting_up)
extern fpu_control_t _dl_fpu_control;
extern int _dl_fpu_control_set;
/* Set nonzero if we have to be prepared for more then one libc being
used in the process. Safe assumption if initializer never runs. */
int __libc_multiple_libcs = 1;
/* Remember the command line argument and enviroment contents for
later calls of initializers for dynamic libraries. */
int __libc_argc;
char **__libc_argv;
static void
init (int argc, char **argv, char **envp)
{
extern void __getopt_clean_environment (char **);
/* The next variable is only here to work around a bug in gcc <= 2.7.2.2.
If the address would be taken inside the expression the optimizer
would try to be too smart and throws it away. Grrr. */
int *dummy_addr = &_dl_starting_up;
__libc_multiple_libcs = dummy_addr && !_dl_starting_up;
/* Make sure we don't initialize twice. */
if (!__libc_multiple_libcs)
{
/* Test whether the kernel is new enough. This test is only
performed if the library is not compiled to run on all
kernels. */
if (__LINUX_KERNEL_VERSION > 0)
{
static const int sysctl_args[] = { CTL_KERN, KERN_OSRELEASE };
char buf[64];
size_t reslen = sizeof (buf);
unsigned int version;
int parts;
char *cp;
/* Try reading the number using `sysctl' first. */
if (__sysctl ((int *) sysctl_args,
sizeof (sysctl_args) / sizeof (sysctl_args[0]),
buf, &reslen, NULL, 0) < 0)
{
/* This was not successful. Now try reading the /proc
filesystem. */
int fd = __open ("/proc/sys/kernel/osrelease", O_RDONLY);
if (fd == -1
|| (reslen = __read (fd, buf, sizeof (buf))) <= 0)
/* This also didn't work. We give up since we cannot
make sure the library can actually work. */
__libc_fatal ("FATAL: cannot determine library version\n");
__close (fd);
}
buf[MIN (reslen, sizeof (buf) - 1)] = '\0';
/* Now convert it into a number. The string consists of at most
three parts. */
version = 0;
parts = 0;
cp = buf;
while ((*cp >= '0') && (*cp <= '9'))
{
unsigned int here = *cp++ - '0';
while ((*cp >= '0') && (*cp <= '9'))
{
here *= 10;
here += *cp++ - '0';
}
++parts;
version <<= 8;
version |= here;
if (*cp++ != '.')
/* Another part following? */
break;
}
if (parts < 3)
version <<= 8 * (3 - parts);
/* Now we can test with the required version. */
if (version < __LINUX_KERNEL_VERSION)
/* Not sufficent. */
__libc_fatal ("FATAL: kernel too old\n");
}
/* Set the FPU control word to the proper default value if the
kernel would use a different value. (In a static program we
don't have this information.) */
#ifdef SHARED
if (__fpu_control != _dl_fpu_control)
#endif
__setfpucw (__fpu_control);
}
/* Save the command-line arguments. */
__libc_argc = argc;
__libc_argv = argv;
__environ = envp;
#ifndef SHARED
__libc_init_secure ();
#endif
__libc_init (argc, argv, envp);
/* This is a hack to make the special getopt in GNU libc working. */
__getopt_clean_environment (envp);
#ifdef SHARED
__libc_global_ctors ();
#endif
}
#ifdef SHARED
strong_alias (init, _init);
void
__libc_init_first (void)
{
}
#else
void
__libc_init_first (int argc, char **argv, char **envp)
{
init (argc, argv, envp);
}
#endif
/* This function is defined here so that if this file ever gets into
ld.so we will get a link error. Having this file silently included
in ld.so causes disaster, because the _init definition above will
cause ld.so to gain an init function, which is not a cool thing. */
void
_dl_start (void)
{
abort ();
}
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