~drizzle-trunk/drizzle/development

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

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

 *

 *  Copyright (C) 2008 Sun Microsystems, Inc.

 *

 *  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 <drizzled/error.h>

#include <drizzled/gettext.h>

#include <drizzled/plugin/error_message.h>

#include <cstdio>

#include <algorithm>

#include <vector>

namespace drizzled

{

std::vector<plugin::ErrorMessage *> all_errmsg_handler;

bool plugin::ErrorMessage::addPlugin(plugin::ErrorMessage *handler)

{

  all_errmsg_handler.push_back(handler);

  return false;

}

void plugin::ErrorMessage::removePlugin(plugin::ErrorMessage *)

{

  all_errmsg_handler.clear();

}

class Print : public std::unary_function<plugin::ErrorMessage *, bool>

{

  error::priority_t priority;

  const char *format;

  va_list ap;

public:

  Print(error::priority_t priority_arg,

        const char *format_arg, va_list ap_arg) : 

    std::unary_function<plugin::ErrorMessage *, bool>(),

    priority(priority_arg), format(format_arg)

  {

    va_copy(ap, ap_arg);

  }

  ~Print()  { va_end(ap); }

  inline result_type operator()(argument_type handler)

  {

    va_list handler_ap;

    va_copy(handler_ap, ap);

    if (handler->errmsg(priority, format, handler_ap))

    {

      /* we're doing the errmsg plugin api,

         so we can't trust the errmsg api to emit our error messages

         so we will emit error messages to stderr */

      /* TRANSLATORS: The leading word "errmsg" is the name

         of the plugin api, and so should not be translated. */

      fprintf(stderr,

              _("errmsg plugin '%s' errmsg() failed"),

              handler->getName().c_str());

      va_end(handler_ap);

      return true;

    }

    va_end(handler_ap);

    return false;

  }

}; 

bool plugin::ErrorMessage::vprintf(error::priority_t priority, char const *format, va_list ap)

{

  if (priority > error::verbosity())

  {

    return false;

  }

  /* 

    Check to see if any errmsg plugin has been loaded

    if not, just fall back to emitting the message to stderr.

  */

  if (all_errmsg_handler.size() == 0)

  {

    /* if it turns out that the vfprintf doesnt do one single write

      (single writes are atomic), then this needs to be rewritten to

      vsprintf into a char buffer, and then write() that char buffer

      to stderr 

    */

    vfprintf(stderr, format, ap);

    fputc('\n', stderr);

    return false;

  }

  /* Use find_if instead of foreach so that we can collect return codes */

  std::vector<plugin::ErrorMessage *>::iterator iter=

    std::find_if(all_errmsg_handler.begin(), all_errmsg_handler.end(),

                 Print(priority, format, ap)); 

  /* If iter is == end() here, that means that all of the plugins returned

   * false, which in this case means they all succeeded. Since we want to 

   * return false on success, we return the value of the two being != 

   */

  return iter != all_errmsg_handler.end();

}

} /* namespace drizzled */