~drizzle-trunk/drizzle/development

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

   Copyright (C) 2006 MySQL AB

   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 "config.h"

#include <cstdio>

#include <cstddef>

#include <gcrypt.h>

#include <drizzled/plugin/function.h>

#include <drizzled/item/func.h>

#include "drizzled/charset.h"

#include <drizzled/function/str/strfunc.h>

using namespace std;

using namespace drizzled;

class Md5Function : public Item_str_func

{

public:

  Md5Function() : Item_str_func() {}

  String *val_str(String*);

  void fix_length_and_dec() 

  {

    max_length= 32;

    args[0]->collation.set(

      get_charset_by_csname(args[0]->collation.collation->csname,

                            MY_CS_BINSORT), DERIVATION_COERCIBLE);

  }

  const char *func_name() const 

  { 

    return "md5"; 

  }

  bool check_argument_count(int n) 

  { 

    return (n == 1); 

  }

};

String *Md5Function::val_str(String *str)

{

  assert(fixed == true);

  String *sptr= args[0]->val_str(str);

  if (sptr == NULL || str->alloc(32)) 

  {

    null_value= true;

    return 0;

  }

  null_value= false;

  str->set_charset(&my_charset_bin);

  gcry_md_hd_t md5_context;

  gcry_md_open(&md5_context, GCRY_MD_MD5, 0);

  gcry_md_write(md5_context, sptr->ptr(), sptr->length());  

  unsigned char *digest= gcry_md_read(md5_context, 0);

  snprintf((char *) str->ptr(), 33,

    "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",

    digest[0], digest[1], digest[2], digest[3],

    digest[4], digest[5], digest[6], digest[7],

    digest[8], digest[9], digest[10], digest[11],

    digest[12], digest[13], digest[14], digest[15]);

  str->length((uint32_t) 32);

  gcry_md_close(md5_context);

  return str;

}

plugin::Create_function<Md5Function> *md5udf= NULL;

static int initialize(module::Context &context)

{

  /* Initialize libgcrypt */

  if (not gcry_check_version(GCRYPT_VERSION))

  {

    errmsg_printf(ERRMSG_LVL_ERROR, _("libgcrypt library version mismatch\n"));

    return 1;

  }

  /* Disable secure memory.  */

  gcry_control (GCRYCTL_DISABLE_SECMEM, 0);

  /* Tell Libgcrypt that initialization has completed. */

  gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);

  md5udf= new plugin::Create_function<Md5Function>("md5");

  context.add(md5udf);

  return 0;

}

DRIZZLE_DECLARE_PLUGIN

{

  DRIZZLE_VERSION_ID,

  "md5",

  "1.0",

  "Stewart Smith",

  "UDF for computing md5sum",

  PLUGIN_LICENSE_GPL,

  initialize, /* Plugin Init */

  NULL,   /* system variables */

  NULL    /* config options */

}

DRIZZLE_DECLARE_PLUGIN_END;