libasm/asm_error.c

/* Error handling in libasm.
   Copyright (C) 2002, 2004, 2005 Red Hat, Inc.
   This file is part of Red Hat elfutils.
   Written by Ulrich Drepper <drepper@redhat.com>, 2002.

   Red Hat elfutils is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by the
   Free Software Foundation; version 2 of the License.

   Red Hat elfutils 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
   General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with Red Hat elfutils; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.

   Red Hat elfutils is an included package of the Open Invention Network.
   An included package of the Open Invention Network is a package for which
   Open Invention Network licensees cross-license their patents.  No patent
   license is granted, either expressly or impliedly, by designation as an
   included package.  Should you wish to participate in the Open Invention
   Network licensing program, please visit www.openinventionnetwork.com
   <http://www.openinventionnetwork.com>.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <libintl.h>
#include <stdbool.h>
#include <stdlib.h>

#include "libasmP.h"


/* This is the key for the thread specific memory.  */
static tls_key_t key;

/* The error number.  Used in non-threaded programs.  */
static int global_error;
static bool threaded;
/* We need to initialize the thread-specific data.  */
once_define (static, once);

/* The initialization and destruction functions.  */
static void init (void);
static void free_key_mem (void *mem);


int
asm_errno (void)
{
  int result;

  /* If we have not yet initialized the buffer do it now.  */
  once_execute (once, init);

  if (threaded)
    {
      /* We have a key.  Use it to get the thread-specific buffer.  */
      int *buffer = getspecific (key);
      if (buffer == NULL)
	{
	  /* No buffer allocated so far.  */
	  buffer = (int *) malloc (sizeof (int));
	  if (buffer == NULL)
	    /* No more memory available.  We use the static buffer.  */
	    buffer = &global_error;

	  setspecific (key, buffer);

	  *buffer = 0;
	}

      result = *buffer;
      *buffer = ASM_E_NOERROR;
      return result;
    }

  result = global_error;
  global_error = ASM_E_NOERROR;
  return result;
}


void
__libasm_seterrno (value)
     int value;
{
  /* If we have not yet initialized the buffer do it now.  */
  once_execute (once, init);

  if (threaded)
    {
      /* We have a key.  Use it to get the thread-specific buffer.  */
      int *buffer = getspecific (key);
      if (buffer == NULL)
        {
          /* No buffer allocated so far.  */
          buffer = malloc (sizeof (int));
          if (buffer == NULL)
            /* No more memory available.  We use the static buffer.  */
            buffer = &global_error;

          setspecific (key, buffer);
        }

      *buffer = value;
    }

  global_error = value;
}


/* Return the appropriate message for the error.  */
static const char *msgs[ASM_E_NUM] =
{
  [ASM_E_NOERROR] = N_("no error"),
  [ASM_E_NOMEM] = N_("out of memory"),
  [ASM_E_CANNOT_CREATE] = N_("cannot create output file"),
  [ASM_E_INVALID] = N_("invalid parameter"),
  [ASM_E_CANNOT_CHMOD] = N_("cannot change mode of output file"),
  [ASM_E_CANNOT_RENAME] = N_("cannot rename output file"),
  [ASM_E_DUPLSYM] = N_("duplicate symbol"),
  [ASM_E_TYPE] = N_("invalid section type for operation"),
  [ASM_E_IOERROR] = N_("error during output of data"),
};

const char *
asm_errmsg (error)
     int error;
{
  int last_error;

  /* If we have not yet initialized the buffer do it now.  */
  once_execute (once, init);

  if ((error == 0 || error == -1) && threaded)
    {
      /* We have a key.  Use it to get the thread-specific buffer.  */
      int *buffer = (int *) getspecific (key);
      if (buffer == NULL)
	{
	  /* No buffer allocated so far.  */
	  buffer = (int *) malloc (sizeof (int));
	  if (buffer == NULL)
	    /* No more memory available.  We use the static buffer.  */
	    buffer = &global_error;

	  setspecific (key, buffer);
	  *buffer = 0;
	}

      last_error = *buffer;
    }
  else
    last_error = global_error;

  if (error < -1)
    return _("unknown error");
  if (error == 0 && last_error == 0)
    /* No error.  */
    return NULL;

  if (error != -1)
    last_error = error;

  if (last_error == ASM_E_LIBELF)
    return elf_errmsg (-1);

  return _(msgs[last_error]);
}


/* Free the thread specific data, this is done if a thread terminates.  */
static void
free_key_mem (void *mem)
{
  free (mem);
  setspecific (key, NULL);
}


/* Initialize the key for the global variable.  */
static void
init (void)
{
  // XXX Screw you, gcc4, the unused function attribute does not work.
  __asm ("" :: "r" (free_key_mem));

  if (key_create (&key, free_key_mem) == 0)
    /* Creating the key succeeded.  */
    threaded = true;
}