/* 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 #include #include #include #include #include #include #include #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 (); }