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

   This program is Open Source software; you can redistribute it and/or
   modify it under the terms of the Open Software License version 1.0 as
   published by the Open Source Initiative.

   You should have received a copy of the Open Software License along
   with this program; if not, you may obtain a copy of the Open Software
   License version 1.0 from http://www.opensource.org/licenses/osl.php or
   by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
   3001 King Ranch Road, Ukiah, CA 95482.   */

#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;
}