glibc/sysdeps/unix/sysv/linux/dl-osinfo.h
2000-09-09 10:08:49 +00:00

121 lines
4.3 KiB
C

/* Operating system specific code for generic dynamic loader functions.
Copyright (C) 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 <string.h>
#include <sys/sysctl.h>
#include <sys/utsname.h>
#include "kernel-features.h"
#ifndef MIN
# define MIN(a,b) (((a)<(b))?(a):(b))
#endif
/* There is no prototype for __sysctl in that file. */
extern int __sysctl (int *name, int nlen, void *oldval,
size_t *oldlenp, void *newval, size_t newlen);
#ifdef SHARED
/* This is the function used in the dynamic linker to print the fatal error
message. */
static inline void
__attribute__ ((__noreturn__))
dl_fatal (const char *str)
{
_dl_sysdep_output (2, str, NULL);
_exit (1);
}
#endif
#define DL_SYSDEP_OSCHECK(FATAL) \
do { \
/* 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 didn't work. Next try the uname syscall */ \
struct utsname uts; \
if (__uname (&uts)) \
{ \
/* 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. */ \
FATAL ("FATAL: cannot determine library version\n"); \
__close (fd); \
} \
else \
{ \
strncpy (buf, uts.release, sizeof (buf)); \
reslen = strlen (uts.release); \
} \
} \
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. */ \
FATAL ("FATAL: kernel too old\n"); \
} \
} while (0)