/* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   Without limiting anything contained in the foregoing, this file,
   which is part of C Driver for MySQL (Connector/C), is also subject to the
   Universal FOSS Exception, version 1.0, a copy of which can be found at
   http://oss.oracle.com/licenses/universal-foss-exception.

   This program 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, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#include "mysys_priv.h"
#include "mysys_err.h"
#include <m_string.h>

/**
  Allocate a sized block of memory.

  @param size   The size of the memory block in bytes.
  @param flags  Failure action modifiers (bitmasks).

  @return A pointer to the allocated memory block, or NULL on failure.
*/
void *my_malloc(size_t size, myf my_flags)
{
  void* point;
  DBUG_ENTER("my_malloc");
  DBUG_PRINT("my",("size: %lu  my_flags: %d", (ulong) size, my_flags));

  /* Safety */
  if (!size)
    size=1;

  point= malloc(size);
  DBUG_EXECUTE_IF("simulate_out_of_memory",
                  {
                    free(point);
                    point= NULL;
                  });
  DBUG_EXECUTE_IF("simulate_persistent_out_of_memory",
                  {
                    free(point);
                    point= NULL;
                  });

  if (point == NULL)
  {
    my_errno=errno;
    if (my_flags & MY_FAE)
      error_handler_hook=fatal_error_handler_hook;
    if (my_flags & (MY_FAE+MY_WME))
      my_error(EE_OUTOFMEMORY, MYF(ME_BELL + ME_WAITTANG +
                                   ME_NOREFRESH + ME_FATALERROR),size);
    DBUG_EXECUTE_IF("simulate_out_of_memory",
                    DBUG_SET("-d,simulate_out_of_memory"););
    if (my_flags & MY_FAE)
      exit(1);
  }
  else if (my_flags & MY_ZEROFILL)
    memset(point, 0, size);
  DBUG_PRINT("exit",("ptr: %p", point));
  DBUG_RETURN(point);
}


/**
   @brief wrapper around realloc()

   @param  oldpoint        pointer to currently allocated area
   @param  size            new size requested, must be >0
   @param  my_flags        flags

   @note if size==0 realloc() may return NULL; my_realloc() treats this as an
   error which is not the intention of realloc()
*/
void *my_realloc(void *oldpoint, size_t size, myf my_flags)
{
  void *point;
  DBUG_ENTER("my_realloc");
  DBUG_PRINT("my",("ptr: %p  size: %lu  my_flags: %d", oldpoint,
                   (ulong) size, my_flags));

  DBUG_ASSERT(size > 0);
  /* These flags are mutually exclusive. */
  DBUG_ASSERT(!((my_flags & MY_FREE_ON_ERROR) &&
                (my_flags & MY_HOLD_ON_ERROR)));
  DBUG_EXECUTE_IF("simulate_out_of_memory",
                  point= NULL;
                  goto end;);
  if (!oldpoint && (my_flags & MY_ALLOW_ZERO_PTR))
    DBUG_RETURN(my_malloc(size, my_flags));
#ifdef USE_HALLOC
  point= malloc(size);
#else
  point= realloc(oldpoint, size);
#endif
#ifndef DBUG_OFF
end:
#endif
  if (point == NULL)
  {
    if (my_flags & MY_HOLD_ON_ERROR)
      DBUG_RETURN(oldpoint);
    if (my_flags & MY_FREE_ON_ERROR)
      my_free(oldpoint);
    my_errno=errno;
    if (my_flags & (MY_FAE+MY_WME))
      my_error(EE_OUTOFMEMORY, MYF(ME_BELL+ ME_WAITTANG + ME_FATALERROR),
               size);
    DBUG_EXECUTE_IF("simulate_out_of_memory",
                    DBUG_SET("-d,simulate_out_of_memory"););
  }
#ifdef USE_HALLOC
  else
  {
    memcpy(point,oldpoint,size);
    free(oldpoint);
  }
#endif
  DBUG_PRINT("exit",("ptr: %p", point));
  DBUG_RETURN(point);
}


/**
  Free memory allocated with my_malloc.

  @remark Relies on free being able to handle a NULL argument.

  @param ptr Pointer to the memory allocated by my_malloc.
*/
void my_free(void *ptr)
{
  DBUG_ENTER("my_free");
  DBUG_PRINT("my",("ptr: %p", ptr));
  free(ptr);
  DBUG_VOID_RETURN;
}


void *my_memdup(const void *from, size_t length, myf my_flags)
{
  void *ptr;
  if ((ptr= my_malloc(length,my_flags)) != 0)
    memcpy(ptr, from, length);
  return ptr;
}


char *my_strdup(const char *from, myf my_flags)
{
  char *ptr;
  size_t length= strlen(from)+1;
  if ((ptr= (char*) my_malloc(length, my_flags)))
    memcpy(ptr, from, length);
  return ptr;
}


char *my_strndup(const char *from, size_t length, myf my_flags)
{
  char *ptr;
  if ((ptr= (char*) my_malloc(length+1, my_flags)))
  {
    memcpy(ptr, from, length);
    ptr[length]= 0;
  }
  return ptr;
}