~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2009 Sun Microsystems

 *

 *  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; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  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 "config.h"

#include <assert.h>

#include "drizzled/identifier.h"

#include "drizzled/session.h"

#include "drizzled/internal/my_sys.h"

#include "drizzled/data_home.h"

#include "drizzled/table.h"

#include "drizzled/util/string.h"

#include <algorithm>

#include <sstream>

#include <cstdio>

#include <boost/thread.hpp>

using namespace std;

namespace drizzled

{

extern std::string drizzle_tmpdir;

extern pid_t current_pid;

static const char hexchars[]= "0123456789abcdef";

static bool tablename_to_filename(const char *from, char *to, size_t to_length);

/*

  Translate a cursor name to a table name (WL #1324).

  SYNOPSIS

    filename_to_tablename()

      from                      The cursor name

      to                OUT     The table name

      to_length                 The size of the table name buffer.

  RETURN

    Table name length.

*/

uint32_t TableIdentifier::filename_to_tablename(const char *from, char *to, uint32_t to_length)

{

  uint32_t length= 0;

  if (!memcmp(from, TMP_FILE_PREFIX, TMP_FILE_PREFIX_LENGTH))

  {

    /* Temporary table name. */

    length= strlen(strncpy(to, from, to_length));

  }

  else

  {

    for (; *from  && length < to_length; length++, from++)

    {

      if (*from != '@')

      {

        to[length]= *from;

        continue;

      }

      /* We've found an escaped char - skip the @ */

      from++;

      to[length]= 0;

      /* There will be a two-position hex-char version of the char */

      for (int x=1; x >= 0; x--)

      {

        if (*from >= '0' && *from <= '9')

          to[length] += ((*from++ - '0') << (4 * x));

        else if (*from >= 'a' && *from <= 'f')

          to[length] += ((*from++ - 'a' + 10) << (4 * x));

      }

      /* Backup because we advanced extra in the inner loop */

      from--;

    } 

  }

  return length;

}

/*

  Creates path to a cursor: drizzle_tmpdir/#sql1234_12_1.ext

  SYNOPSIS

   build_tmptable_filename()

     session                    The thread handle.

     buff                       Where to write result

     bufflen                    buff size

  NOTES

    Uses current_pid, thread_id, and tmp_table counter to create

    a cursor name in drizzle_tmpdir.

  RETURN

    path length on success, 0 on failure

*/

#ifdef _GLIBCXX_HAVE_TLS 

__thread uint32_t counter= 0;

static uint32_t get_counter()

{

  return ++counter;

}

#else

boost::mutex counter_mutex;

static uint32_t counter= 1;

static uint32_t get_counter()

{

  boost::mutex::scoped_lock lock(counter_mutex);

  uint32_t x;

  x= ++counter;

  return x;

}

#endif

size_t TableIdentifier::build_tmptable_filename(std::string &buffer)

{

  size_t tmpdir_length;

  ostringstream post_tmpdir_str;

  buffer.append(drizzle_tmpdir);

  tmpdir_length= buffer.length();

  post_tmpdir_str << "/" << TMP_FILE_PREFIX << current_pid;

  post_tmpdir_str << pthread_self() << "-" << get_counter();

  buffer.append(post_tmpdir_str.str());

  transform(buffer.begin() + tmpdir_length, buffer.end(), buffer.begin() + tmpdir_length, ::tolower);

  return buffer.length();

}

size_t TableIdentifier::build_tmptable_filename(std::vector<char> &buffer)

{

  ostringstream post_tmpdir_str;

  post_tmpdir_str << drizzle_tmpdir << "/" << TMP_FILE_PREFIX << current_pid;

  post_tmpdir_str << pthread_self() << "-" << get_counter();

  buffer.resize(post_tmpdir_str.str().length() + 1);

  memcpy(&buffer[0], post_tmpdir_str.str().c_str(), post_tmpdir_str.str().size());

  buffer[post_tmpdir_str.str().size()]= 0;

  return buffer.size();

}

/*

  Creates path to a cursor: drizzle_data_dir/db/table.ext

  SYNOPSIS

   build_table_filename()

     buff                       Where to write result

                                This may be the same as table_name.

     bufflen                    buff size

     db                         Database name

     table_name                 Table name

     ext                        File extension.

     flags                      table_name is temporary, do not change.

  NOTES

    Uses database and table name, and extension to create

    a cursor name in drizzle_data_dir. Database and table

    names are converted from system_charset_info into "fscs".

    Unless flags indicate a temporary table name.

    'db' is always converted.

    'ext' is not converted.

    The conversion suppression is required for ALTER Table. This

    statement creates intermediate tables. These are regular

    (non-temporary) tables with a temporary name. Their path names must

    be derivable from the table name. So we cannot use

    build_tmptable_filename() for them.

  RETURN

    path length on success, 0 on failure

*/

size_t TableIdentifier::build_table_filename(std::string &path, const char *db, const char *table_name, bool is_tmp)

{

  char dbbuff[FN_REFLEN];

  char tbbuff[FN_REFLEN];

  bool conversion_error= false;

  memset(tbbuff, 0, sizeof(tbbuff));

  if (is_tmp) // It a conversion tmp

  {

    strncpy(tbbuff, table_name, sizeof(tbbuff));

  }

  else

  {

    conversion_error= tablename_to_filename(table_name, tbbuff, sizeof(tbbuff));

    if (conversion_error)

    {

      errmsg_printf(ERRMSG_LVL_ERROR,

                    _("Table name cannot be encoded and fit within filesystem "

                      "name length restrictions."));

      return 0;

    }

  }

  memset(dbbuff, 0, sizeof(dbbuff));

  conversion_error= tablename_to_filename(db, dbbuff, sizeof(dbbuff));

  if (conversion_error)

  {

    errmsg_printf(ERRMSG_LVL_ERROR,

                  _("Schema name cannot be encoded and fit within filesystem "

                    "name length restrictions."));

    return 0;

  }

  int rootdir_len= strlen(FN_ROOTDIR);

  path.append(data_home);

  ssize_t without_rootdir= path.length() - rootdir_len;

  /* Don't add FN_ROOTDIR if dirzzle_data_home already includes it */

  if (without_rootdir >= 0)

  {

    const char *tmp= path.c_str() + without_rootdir;

    if (memcmp(tmp, FN_ROOTDIR, rootdir_len) != 0)

      path.append(FN_ROOTDIR);

  }

  path.append(dbbuff);

  path.append(FN_ROOTDIR);

  path.append(tbbuff);

  return path.length();

}

/*

  Translate a table name to a cursor name (WL #1324).

  SYNOPSIS

    tablename_to_filename()

      from                      The table name

      to                OUT     The cursor name

      to_length                 The size of the cursor name buffer.

  RETURN

    true if errors happen. false on success.

*/

static bool tablename_to_filename(const char *from, char *to, size_t to_length)

{

  size_t length= 0;

  for (; *from  && length < to_length; length++, from++)

  {

    if ((*from >= '0' && *from <= '9') ||

        (*from >= 'a' && *from <= 'z') ||

/* OSX defines an extra set of high-bit and multi-byte characters

   that cannot be used on the filesystem. Instead of trying to sort

   those out, we'll just escape encode all high-bit-set chars on OSX.

   It won't really hurt anything - it'll just make some filenames ugly. */

#if !defined(TARGET_OS_OSX)

        ((unsigned char)*from >= 128) ||

#endif

        (*from == '_') ||

        (*from == ' ') ||

        (*from == '-'))

    {

      to[length]= tolower(*from);

      continue;

    }

    if ((*from >= 'A' && *from <= 'Z'))

    {

      to[length]= tolower(*from);

      continue;

    }

    if (length + 3 >= to_length)

      return true;

    /* We need to escape this char in a way that can be reversed */

    to[length++]= '@';

    to[length++]= hexchars[(*from >> 4) & 15];

    to[length]= hexchars[(*from) & 15];

  }

  if (internal::check_if_legal_tablename(to) &&

      length + 4 < to_length)

  {

    memcpy(to + length, "@@@", 4);

    length+= 3;

  }

  return false;

}

TableIdentifier::TableIdentifier(const drizzled::Table &table) :

  SchemaIdentifier(table.getShare()->getSchemaName()),

  type(table.getShare()->getTableType()),

  table_name(table.getShare()->getTableName())

{

  if (type == message::Table::TEMPORARY)

    path= table.getShare()->getPath();

  init();

}

void TableIdentifier::init()

{

  switch (type) {

  case message::Table::FUNCTION:

  case message::Table::STANDARD:

    assert(path.size() == 0);

    build_table_filename(path, getSchemaName().c_str(), table_name.c_str(), false);

    break;

  case message::Table::INTERNAL:

    assert(path.size() == 0);

    build_table_filename(path, getSchemaName().c_str(), table_name.c_str(), true);

    break;

  case message::Table::TEMPORARY:

    if (path.empty())

    {

      build_tmptable_filename(path);

    }

    break;

  }

  util::insensitive_hash hasher;

  hash_value= hasher(path);

  key.resize(getKeySize());

  size_t key_length= TableIdentifier::createKey(&key[0], *this);

  assert(key_length == getKeySize()); // If this is off, then we have a memory issue.

}

const std::string &TableIdentifier::getPath() const

{

  return path;

}

const std::string &TableIdentifier::getSQLPath()  // @todo this is just used for errors, we should find a way to optimize it

{

  if (sql_path.empty())

  {

    switch (type) {

    case message::Table::FUNCTION:

    case message::Table::STANDARD:

      sql_path.append(getSchemaName());

      sql_path.append(".");

      sql_path.append(table_name);

      break;

    case message::Table::INTERNAL:

      sql_path.append("temporary.");

      sql_path.append(table_name);

      break;

    case message::Table::TEMPORARY:

      sql_path.append(getSchemaName());

      sql_path.append(".#");

      sql_path.append(table_name);

      break;

    }

  }

  return sql_path;

}

void TableIdentifier::copyToTableMessage(message::Table &message) const

{

  message.set_name(table_name);

  message.set_schema(getSchemaName());

}

std::size_t hash_value(TableIdentifier const& b)

{

  return b.getHashValue();

}

} /* namespace drizzled */