/* Copyright (c) 2000, 2014, 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 as published by
   the Free Software Foundation; version 2 of the License.

   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 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 <m_string.h>
#include "prealloced_array.h"
#include "mutex_lock.h"

#if defined(_WIN32)
#define DELIM ';'
#else
#define DELIM ':'
#endif

my_bool init_tmpdir(MY_TMPDIR *tmpdir, const char *pathlist)
{
  char *end, *copy;
  char buff[FN_REFLEN];
  DBUG_ENTER("init_tmpdir");
  DBUG_PRINT("enter", ("pathlist: %s", pathlist ? pathlist : "NULL"));

  Prealloced_array<char*, 10, true> full_list(key_memory_MY_TMPDIR_full_list);

  memset(tmpdir, 0, sizeof(*tmpdir));
  if (!pathlist || !pathlist[0])
  {
    /* Get default temporary directory */
    pathlist=getenv("TMPDIR");	/* Use this if possible */
#if defined(_WIN32)
    if (!pathlist)
      pathlist=getenv("TEMP");
    if (!pathlist)
      pathlist=getenv("TMP");
#endif
    if (!pathlist || !pathlist[0])
      pathlist= DEFAULT_TMPDIR;
  }
  do
  {
    size_t length;
    end=strcend(pathlist, DELIM);
    strmake(buff, pathlist, (uint) (end-pathlist));
    length= cleanup_dirname(buff, buff);
    if (!(copy= my_strndup(key_memory_MY_TMPDIR_full_list,
                           buff, length, MYF(MY_WME))) ||
        full_list.push_back(copy))
      DBUG_RETURN(TRUE);
    pathlist=end+1;
  }
  while (*end);

  tmpdir->list=
    static_cast<char**>(my_malloc(key_memory_MY_TMPDIR_full_list,
                                  sizeof(char*) * full_list.size(),
                                  MYF(MY_WME)));
  if (tmpdir->list == NULL)
    DBUG_RETURN(TRUE);

  mysql_mutex_init(key_TMPDIR_mutex, &tmpdir->mutex, MY_MUTEX_INIT_FAST);
  memcpy(tmpdir->list, &full_list[0], sizeof(char*) * full_list.size());
  tmpdir->max= full_list.size() - 1;
  tmpdir->cur= 0;
  DBUG_RETURN(FALSE);
}


char *my_tmpdir(MY_TMPDIR *tmpdir)
{
  if (0 == tmpdir->max)
    return tmpdir->list[0];

  Mutex_lock(&tmpdir->mutex);
  char *dir= tmpdir->list[tmpdir->cur];
  tmpdir->cur= (tmpdir->cur == tmpdir->max) ? 0 : tmpdir->cur + 1;

  return dir;
}


void free_tmpdir(MY_TMPDIR *tmpdir)
{
  if (tmpdir->list == NULL)
    return;
  for (uint i= 0; i <= tmpdir->max; i++)
    my_free(tmpdir->list[i]);
  my_free(tmpdir->list);
  mysql_mutex_destroy(&tmpdir->mutex);
}