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/* Copyright (C) 1998 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 <stdlib.h>
#include <unistd.h>
#include <elf/ldsodefs.h>
extern void __libc_init_first (int argc, char **argv, char **envp);
extern int _dl_starting_up;
weak_extern (_dl_starting_up)
extern int __libc_multiple_libcs;
extern void *__libc_stack_end;
struct startup_info
{
void *sda_base;
int (*main) (int, char **, char **, void *);
int (*init) (int, char **, char **, void *);
void (*fini) (void);
};
int
__libc_start_main (int argc, char **argv, char **envp,
void *auxvec, void (*rtld_fini) (void),
struct startup_info *stinfo,
char **stack_on_entry)
{
#ifndef PIC
/* 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;
#endif
/* the PPC SVR4 ABI says that the top thing on the stack will
be a NULL pointer, so if not we assume that we're being called
as a statically-linked program by Linux... */
if (*stack_on_entry != NULL)
{
/* ...in which case, we have argc as the top thing on the
stack, followed by argv (NULL-terminated), envp (likewise),
and the auxilary vector. */
argc = *(int *) stack_on_entry;
argv = stack_on_entry + 1;
envp = argv + argc + 1;
auxvec = envp;
while (*(char **) auxvec != NULL)
++auxvec;
++auxvec;
rtld_fini = NULL;
}
/* Store something that has some relationship to the end of the
stack, for backtraces. This variable should be thread-specific. */
__libc_stack_end = stack_on_entry + 4;
/* Set the global _environ variable correctly. */
__environ = envp;
/* Register the destructor of the dynamic linker if there is any. */
if (rtld_fini != NULL)
atexit (rtld_fini);
/* Call the initializer of the libc. */
#ifdef PIC
if (_dl_debug_impcalls)
_dl_debug_message (1, "\ninitialize libc\n\n", NULL);
#endif
__libc_init_first (argc, argv, envp);
/* Register the destructor of the program, if any. */
if (stinfo->fini)
atexit (stinfo->fini);
/* Call the initializer of the program, if any. */
#ifdef PIC
if (_dl_debug_impcalls)
_dl_debug_message (1, "\ninitialize program: ", argv[0], "\n\n", NULL);
#endif
if (stinfo->init)
stinfo->init (argc, argv, __environ, auxvec);
#ifdef PIC
if (_dl_debug_impcalls)
_dl_debug_message (1, "\ntransferring control: ", argv[0], "\n\n", NULL);
#endif
exit (stinfo->main (argc, argv, __environ, auxvec));
}
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