glibc/sysdeps/powerpc/elf/libc-start.c

/* Copyright (C) 1998,2000,2001,2002 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 Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; 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 <ldsodefs.h>
#include <bp-start.h>
#include <bp-sym.h>

extern void __libc_init_first (int argc, char **argv, char **envp);

extern int _dl_starting_up;
weak_extern (_dl_starting_up)

extern int __cache_line_size;
weak_extern (__cache_line_size)

extern int __libc_multiple_libcs;
extern void *__libc_stack_end;

struct startup_info
{
  void *__unbounded sda_base;
  int (*main) (int, char **, char **, void *);
  int (*init) (int, char **, char **, void *);
  void (*fini) (void);
};

/* Scan the Aux Vector for the "Data Cache Block Size" entry.  If found
   verify that the static extern __cache_line_size is defined by checking
   for not NULL.  If it is defined then assign the cache block size 
   value to __cache_line_size.  */
static inline void
__aux_init_cache (ElfW(auxv_t) *av)
{
  for (; av->a_type != AT_NULL; ++av)
    switch (av->a_type)
      {
      case AT_DCACHEBSIZE:
        {
          int *cls = & __cache_line_size;
          if (cls != NULL)
            *cls = av->a_un.a_val;
        }
        break;
      }
}


int
/* GKM FIXME: GCC: this should get __BP_ prefix by virtue of the
   BPs in the arglist of startup_info.main and startup_info.init. */
BP_SYM (__libc_start_main) (int argc, char *__unbounded *__unbounded ubp_av,
		   char *__unbounded *__unbounded ubp_ev,
		   ElfW(auxv_t) *__unbounded auxvec, void (*rtld_fini) (void),
		   struct startup_info *__unbounded stinfo,
		   char *__unbounded *__unbounded stack_on_entry)
{
#if __BOUNDED_POINTERS__
  char **argv;
#else
# define argv ubp_av
#endif

#ifndef SHARED
  /* 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)
    {
      char *__unbounded *__unbounded temp;
      /* ...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 *__unbounded) stack_on_entry;
      ubp_av = stack_on_entry + 1;
      ubp_ev = ubp_av + argc + 1;
#ifdef HAVE_AUX_VECTOR
      temp = ubp_ev;
      while (*temp != NULL)
        ++temp;
      auxvec = (ElfW(auxv_t) *)++temp;
      

# ifndef SHARED
      _dl_aux_init ((ElfW(auxv_t) *) auxvec);
# endif
#endif
      rtld_fini = NULL;
    }

  INIT_ARGV_and_ENVIRON;
    
  /* Initialize the __cache_line_size variable from the aux vector.  */
  __aux_init_cache((ElfW(auxv_t) *) auxvec);

  /* 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;

  /* Register the destructor of the dynamic linker if there is any.  */
  if (rtld_fini != NULL)
    __cxa_atexit ((void (*) (void *)) rtld_fini, NULL, NULL);

  /* Call the initializer of the libc.  */
#ifdef SHARED
  if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0))
    _dl_debug_printf ("\ninitialize libc\n\n");
#endif
  __libc_init_first (argc, argv, __environ);

  /* Register the destructor of the program, if any.  */
  if (stinfo->fini)
    __cxa_atexit ((void (*) (void *)) stinfo->fini, NULL, NULL);

  /* Call the initializer of the program, if any.  */
#ifdef SHARED
  if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0))
    _dl_debug_printf ("\ninitialize program: %s\n\n", argv[0]);
#endif
  if (stinfo->init)
    stinfo->init (argc, argv, __environ, auxvec);

#ifdef SHARED
  if (__builtin_expect (GL(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0))
    _dl_debug_printf ("\ntransferring control: %s\n\n", argv[0]);
#endif

  exit (stinfo->main (argc, argv, __environ, auxvec));
}