Subversion Repositories openrisc_2011-10-31

/* Error handling for runtime dynamic linker.

   Copyright (C) 1995,96,97,98,99,2000,2001 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 <libintl.h>

#include <setjmp.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <ldsodefs.h>

#include <sys/libc-tsd.h>

/* This structure communicates state between _dl_catch_error and

   _dl_signal_error.  */

struct catch

  {

    const char *objname;        /* Object/File name.  */

    const char *errstring;      /* Error detail filled in here.  */

    jmp_buf env;                /* longjmp here on error.  */

  };

/* Multiple threads at once can use the `_dl_catch_error' function.  The

   calls can come from `_dl_map_object_deps', `_dlerror_run', or from

   any of the libc functionality which loads dynamic objects (NSS, iconv).

   Therefore we have to be prepared to save the state in thread-local

   memory.  */

__libc_tsd_define (static, DL_ERROR)

#define tsd_getspecific()       __libc_tsd_get (DL_ERROR)

#define tsd_setspecific(data)   __libc_tsd_set (DL_ERROR, (data))

/* This message we return as a last resort.  We define the string in a

   variable since we have to avoid freeing it and so have to enable

   a pointer comparison.  See below and in dlfcn/dlerror.c.  */

const char _dl_out_of_memory[] = "out of memory";

/* This points to a function which is called when an continuable error is

   received.  Unlike the handling of `catch' this function may return.

   The arguments will be the `errstring' and `objname'.

   Since this functionality is not used in normal programs (only in ld.so)

   we do not care about multi-threaded programs here.  We keep this as a

   global variable.  */

static receiver_fct receiver;

void

internal_function

_dl_signal_error (int errcode, const char *objname, const char *occation,

                  const char *errstring)

{

  struct catch *lcatch;

  if (! errstring)

    errstring = N_("DYNAMIC LINKER BUG!!!");

  lcatch = tsd_getspecific ();

  if (objname == NULL)

    objname = "";

  if (lcatch != NULL)

    {

      /* We are inside _dl_catch_error.  Return to it.  We have to

         duplicate the error string since it might be allocated on the

         stack.  The object name is always a string constant.  */

      size_t len_objname = strlen (objname) + 1;

      size_t len_errstring = strlen (errstring) + 1;

      lcatch->errstring = (char *) malloc (len_objname + len_errstring);

      if (lcatch->errstring != NULL)

        {

          char *tmp;

          /* Make a copy of the object file name and the error string.  */

          tmp = memcpy ((char *) lcatch->errstring,

                           errstring, len_errstring);

          tmp += len_errstring;

          lcatch->objname = memcpy (tmp,

                                  objname, len_objname);

        }

      else

        {

          /* This is better than nothing.  */

          lcatch->objname = "";

          lcatch->errstring = _dl_out_of_memory;

        }

      longjmp (lcatch->env, errcode ?: -1);

    }

  else

    {

      /* Lossage while resolving the program's own symbols is always fatal.  */

      char buffer[1024];

      _dl_fatal_printf ("%s: %s: %s%s%s%s%s\n",

                        _dl_argv[0] ?: "<program name unknown>",

                        occation ?: N_("error while loading shared libraries"),

                        objname, *objname ? ": " : "",

                        errstring, errcode ? ": " : "",

                        (errcode

                         ? __strerror_r (errcode, buffer, sizeof buffer)

                         : ""));

    }

}

void

internal_function

_dl_signal_cerror (int errcode, const char *objname, const char *occation,

                   const char *errstring)

{

  if (receiver)

    {

      /* We are inside _dl_receive_error.  Call the user supplied

         handler and resume the work.  The receiver will still be

         installed.  */

      (*receiver) (errcode, objname, errstring);

    }

  else

    _dl_signal_error (errcode, objname, occation, errstring);

}

int

internal_function

_dl_catch_error (const char **objname, const char **errstring,

                 void (*operate) (void *), void *args)

{

  int errcode;

  struct catch *volatile old;

  struct catch c;

  /* We need not handle `receiver' since setting a `catch' is handled

     before it.  */

  /* Some systems (e.g., SPARC) handle constructors to local variables

     inefficient.  So we initialize `c' by hand.  */

  c.errstring = NULL;

  old = tsd_getspecific ();

  errcode = setjmp (c.env);

  if (__builtin_expect (errcode, 0) == 0)

    {

      tsd_setspecific (&c);

      (*operate) (args);

      tsd_setspecific (old);

      *objname = NULL;

      *errstring = NULL;

      return 0;

    }

  /* We get here only if we longjmp'd out of OPERATE.  */

  tsd_setspecific (old);

  *objname = c.objname;

  *errstring = c.errstring;

  return errcode == -1 ? 0 : errcode;

}

void

internal_function

_dl_receive_error (receiver_fct fct, void (*operate) (void *), void *args)

{

  struct catch *old_catch;

  receiver_fct old_receiver;

  old_catch = tsd_getspecific ();

  old_receiver = receiver;

  /* Set the new values.  */

  tsd_setspecific (NULL);

  receiver = fct;

  (*operate) (args);

  tsd_setspecific (old_catch);

  receiver = old_receiver;

}