/* GLIB - Library of useful routines for C programming

 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 */

/*

 * Modified by the GLib Team and others 1997-2000.  See the AUTHORS

 * file for a list of people on the GLib Team.  See the ChangeLog

 * files for a list of changes.  These files are distributed with

 * GLib at ftp://ftp.gtk.org/pub/gtk/.

 */

/*

 * MT safe

 */

/**

 * SECTION:warnings

 * @Title: Message Output and Debugging Functions

 * @Short_description: functions to output messages and help debug applications

 *

 * These functions provide support for outputting messages.

 *

 * The <function>g_return</function> family of macros (g_return_if_fail(),

 * g_return_val_if_fail(), g_return_if_reached(), g_return_val_if_reached())

 * should only be used for programming errors, a typical use case is

 * checking for invalid parameters at the beginning of a public function.

 * They should not be used if you just mean "if (error) return", they

 * should only be used if you mean "if (bug in program) return".

 * The program behavior is generally considered undefined after one

 * of these checks fails. They are not intended for normal control

 * flow, only to give a perhaps-helpful warning before giving up.

 */

#include "config.h"

#include <stdlib.h>

#include <stdarg.h>

#include <stdio.h>

#include <string.h>

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif

#include <signal.h>

#include <locale.h>

#include <errno.h>

#include "gmessages.h"

#include "glib-init.h"

#include "gbacktrace.h"

#include "gcharset.h"

#include "gconvert.h"

#include "genviron.h"

#include "gmem.h"

#include "gprintfint.h"

#include "gtestutils.h"

#include "gthread.h"

#include "gstrfuncs.h"

#include "gstring.h"

#ifdef G_OS_WIN32

#include <process.h>		/* For getpid() */

#include <io.h>

#  define _WIN32_WINDOWS 0x0401 /* to get IsDebuggerPresent */

#  include <windows.h>

#endif

/**

 * SECTION:messages

 * @title: Message Logging

 * @short_description: versatile support for logging messages

 *     with different levels of importance

 *

 * These functions provide support for logging error messages

 * or messages used for debugging.

 *

 * There are several built-in levels of messages, defined in

 * #GLogLevelFlags. These can be extended with user-defined levels.

 */

/**

 * G_LOG_DOMAIN:

 *

 * Defines the log domain.

 *

 * For applications, this is typically left as the default %NULL

 * (or "") domain. Libraries should define this so that any messages

 * which they log can be differentiated from messages from other

 * libraries and application code. But be careful not to define

 * it in any public header files.

 *

 * For example, GTK+ uses this in its Makefile.am:

 * |[

 * INCLUDES = -DG_LOG_DOMAIN=\"Gtk\"

 * ]|

 */

/**

 * G_LOG_FATAL_MASK:

 *

 * GLib log levels that are considered fatal by default.

 */

/**

 * GLogFunc:

 * @log_domain: the log domain of the message

 * @log_level: the log level of the message (including the

 *     fatal and recursion flags)

 * @message: the message to process

 * @user_data: user data, set in g_log_set_handler()

 *

 * Specifies the prototype of log handler functions.

 */

/**

 * GLogLevelFlags:

 * @G_LOG_FLAG_RECURSION: internal flag

 * @G_LOG_FLAG_FATAL: internal flag

 * @G_LOG_LEVEL_ERROR: log level for errors, see g_error().

 *     This level is also used for messages produced by g_assert().

 * @G_LOG_LEVEL_CRITICAL: log level for critical messages, see g_critical().

 *     This level is also used for messages produced by g_return_if_fail()

 *     and g_return_val_if_fail().

 * @G_LOG_LEVEL_WARNING: log level for warnings, see g_warning()

 * @G_LOG_LEVEL_MESSAGE: log level for messages, see g_message()

 * @G_LOG_LEVEL_INFO: log level for informational messages

 * @G_LOG_LEVEL_DEBUG: log level for debug messages, see g_debug()

 * @G_LOG_LEVEL_MASK: a mask including all log levels

 *

 * Flags specifying the level of log messages.

 *

 * It is possible to change how GLib treats messages of the various

 * levels using g_log_set_handler() and g_log_set_fatal_mask().

 */

/**

 * g_message:

 * @...: format string, followed by parameters to insert

 *     into the format string (as with printf())

 *

 * A convenience function/macro to log a normal message.

 */

/**

 * g_warning:

 * @...: format string, followed by parameters to insert

 *     into the format string (as with printf())

 *

 * A convenience function/macro to log a warning message.

 *

 * You can make warnings fatal at runtime by setting the

 * <envar>G_DEBUG</envar> environment variable (see

 * <ulink url="glib-running.html">Running GLib Applications</ulink>).

 */

/**

 * g_critical:

 * @...: format string, followed by parameters to insert

 *     into the format string (as with printf())

 *

 * Logs a "critical warning" (#G_LOG_LEVEL_CRITICAL).

 * It's more or less application-defined what constitutes

 * a critical vs. a regular warning. You could call

 * g_log_set_always_fatal() to make critical warnings exit

 * the program, then use g_critical() for fatal errors, for

 * example.

 *

 * You can also make critical warnings fatal at runtime by

 * setting the <envar>G_DEBUG</envar> environment variable (see

 * <ulink url="glib-running.html">Running GLib Applications</ulink>).

 */

/**

 * g_error:

 * @...: format string, followed by parameters to insert

 *     into the format string (as with printf())

 *

 * A convenience function/macro to log an error message.

 *

 * Error messages are always fatal, resulting in a call to

 * abort() to terminate the application. This function will

 * result in a core dump; don't use it for errors you expect.

 * Using this function indicates a bug in your program, i.e.

 * an assertion failure.

 *

 */

/**

 * g_debug:

 * @...: format string, followed by parameters to insert

 *     into the format string (as with printf())

 *

 * A convenience function/macro to log a debug message.

 *

 * Since: 2.6

 */

/* --- structures --- */

typedef struct _GLogDomain	GLogDomain;

typedef struct _GLogHandler	GLogHandler;

struct _GLogDomain

{

  gchar		*log_domain;

  GLogLevelFlags fatal_mask;

  GLogHandler	*handlers;

  GLogDomain	*next;

};

struct _GLogHandler

{

  guint		 id;

  GLogLevelFlags log_level;

  GLogFunc	 log_func;

  gpointer	 data;

  GLogHandler	*next;

};

/* --- variables --- */

static GMutex         g_messages_lock;

static GLogDomain    *g_log_domains = NULL;

static GPrintFunc     glib_print_func = NULL;

static GPrintFunc     glib_printerr_func = NULL;

static GPrivate       g_log_depth;

static GLogFunc       default_log_func = g_log_default_handler;

static gpointer       default_log_data = NULL;

static GTestLogFatalFunc fatal_log_func = NULL;

static gpointer          fatal_log_data;

/* --- functions --- */

#ifdef G_OS_WIN32

#  include <windows.h>

static gboolean win32_keep_fatal_message = FALSE;

/* This default message will usually be overwritten. */

/* Yes, a fixed size buffer is bad. So sue me. But g_error() is never

 * called with huge strings, is it?

 */

static gchar  fatal_msg_buf[1000] = "Unspecified fatal error encountered, aborting.";

static gchar *fatal_msg_ptr = fatal_msg_buf;

#undef write

static inline int

dowrite (int          fd,

	 const void  *buf,

	 unsigned int len)

{

  if (win32_keep_fatal_message)

    {

      memcpy (fatal_msg_ptr, buf, len);

      fatal_msg_ptr += len;

      *fatal_msg_ptr = 0;

      return len;

    }

  write (fd, buf, len);

  return len;

}

#define write(fd, buf, len) dowrite(fd, buf, len)

#endif

static void

write_string (int          fd,

	      const gchar *string)

{

  write (fd, string, strlen (string));

}

static GLogDomain*

g_log_find_domain_L (const gchar *log_domain)

{

  register GLogDomain *domain;

  domain = g_log_domains;

  while (domain)

    {

      if (strcmp (domain->log_domain, log_domain) == 0)

	return domain;

      domain = domain->next;

    }

  return NULL;

}

static GLogDomain*

g_log_domain_new_L (const gchar *log_domain)

{

  register GLogDomain *domain;

  domain = g_new (GLogDomain, 1);

  domain->log_domain = g_strdup (log_domain);

  domain->fatal_mask = G_LOG_FATAL_MASK;

  domain->handlers = NULL;

  domain->next = g_log_domains;

  g_log_domains = domain;

  return domain;

}

static void

g_log_domain_check_free_L (GLogDomain *domain)

{

  if (domain->fatal_mask == G_LOG_FATAL_MASK &&

      domain->handlers == NULL)

    {

      register GLogDomain *last, *work;

      last = NULL;  

      work = g_log_domains;

      while (work)

	{

	  if (work == domain)

	    {

	      if (last)

		last->next = domain->next;

	      else

		g_log_domains = domain->next;

	      g_free (domain->log_domain);

	      g_free (domain);

	      break;

	    }

	  last = work;

	  work = last->next;

	}  

    }

}

static GLogFunc

g_log_domain_get_handler_L (GLogDomain	*domain,

			    GLogLevelFlags log_level,

			    gpointer	*data)

{

  if (domain && log_level)

    {

      register GLogHandler *handler;

      handler = domain->handlers;

      while (handler)

	{

	  if ((handler->log_level & log_level) == log_level)

	    {

	      *data = handler->data;

	      return handler->log_func;

	    }

	  handler = handler->next;

	}

    }

  *data = default_log_data;

  return default_log_func;

}

/**

 * g_log_set_always_fatal:

 * @fatal_mask: the mask containing bits set for each level

 *     of error which is to be fatal

 *

 * Sets the message levels which are always fatal, in any log domain.

 * When a message with any of these levels is logged the program terminates.

 * You can only set the levels defined by GLib to be fatal.

 * %G_LOG_LEVEL_ERROR is always fatal.

 *

 * You can also make some message levels fatal at runtime by setting

 * the <envar>G_DEBUG</envar> environment variable (see

 * <ulink url="glib-running.html">Running GLib Applications</ulink>).

 *

 * Returns: the old fatal mask

 */

GLogLevelFlags

g_log_set_always_fatal (GLogLevelFlags fatal_mask)

{

  GLogLevelFlags old_mask;

  /* restrict the global mask to levels that are known to glib

   * since this setting applies to all domains

   */

  fatal_mask &= (1 << G_LOG_LEVEL_USER_SHIFT) - 1;

  /* force errors to be fatal */

  fatal_mask |= G_LOG_LEVEL_ERROR;

  /* remove bogus flag */

  fatal_mask &= ~G_LOG_FLAG_FATAL;

  g_mutex_lock (&g_messages_lock);

  old_mask = g_log_always_fatal;

  g_log_always_fatal = fatal_mask;

  g_mutex_unlock (&g_messages_lock);

  return old_mask;

}

/**

 * g_log_set_fatal_mask:

 * @log_domain: the log domain

 * @fatal_mask: the new fatal mask

 *

 * Sets the log levels which are fatal in the given domain.

 * %G_LOG_LEVEL_ERROR is always fatal.

 *

 * Returns: the old fatal mask for the log domain

 */

GLogLevelFlags

g_log_set_fatal_mask (const gchar   *log_domain,

		      GLogLevelFlags fatal_mask)

{

  GLogLevelFlags old_flags;

  register GLogDomain *domain;

  if (!log_domain)

    log_domain = "";

  /* force errors to be fatal */

  fatal_mask |= G_LOG_LEVEL_ERROR;

  /* remove bogus flag */

  fatal_mask &= ~G_LOG_FLAG_FATAL;

  g_mutex_lock (&g_messages_lock);

  domain = g_log_find_domain_L (log_domain);

  if (!domain)

    domain = g_log_domain_new_L (log_domain);

  old_flags = domain->fatal_mask;

  domain->fatal_mask = fatal_mask;

  g_log_domain_check_free_L (domain);

  g_mutex_unlock (&g_messages_lock);

  return old_flags;

}

/**

 * g_log_set_handler:

 * @log_domain: (allow-none): the log domain, or %NULL for the default ""

 *     application domain

 * @log_levels: the log levels to apply the log handler for.

 *     To handle fatal and recursive messages as well, combine

 *     the log levels with the #G_LOG_FLAG_FATAL and

 *     #G_LOG_FLAG_RECURSION bit flags.

 * @log_func: the log handler function

 * @user_data: data passed to the log handler

 *

 * Sets the log handler for a domain and a set of log levels.

 * To handle fatal and recursive messages the @log_levels parameter

 * must be combined with the #G_LOG_FLAG_FATAL and #G_LOG_FLAG_RECURSION

 * bit flags.

 *

 * Note that since the #G_LOG_LEVEL_ERROR log level is always fatal, if

 * you want to set a handler for this log level you must combine it with

 * #G_LOG_FLAG_FATAL.

 *

 * <example>

 * <title>Adding a log handler for all warning messages in the default

 * (application) domain</title>

 * <programlisting>

 * g_log_set_handler (NULL, G_LOG_LEVEL_WARNING | G_LOG_FLAG_FATAL

 *                    | G_LOG_FLAG_RECURSION, my_log_handler, NULL);

 * </programlisting>

 * </example>

 *

 * <example>

 * <title>Adding a log handler for all critical messages from GTK+</title>

 * <programlisting>

 * g_log_set_handler ("Gtk", G_LOG_LEVEL_CRITICAL | G_LOG_FLAG_FATAL

 *                    | G_LOG_FLAG_RECURSION, my_log_handler, NULL);

 * </programlisting>

 * </example>

 *

 * <example>

 * <title>Adding a log handler for <emphasis>all</emphasis> messages from

 * GLib</title>

 * <programlisting>

 * g_log_set_handler ("GLib", G_LOG_LEVEL_MASK | G_LOG_FLAG_FATAL

 *                    | G_LOG_FLAG_RECURSION, my_log_handler, NULL);

 * </programlisting>

 * </example>

 *

 * Returns: the id of the new handler

 */

guint

g_log_set_handler (const gchar	 *log_domain,

		   GLogLevelFlags log_levels,

		   GLogFunc	  log_func,

		   gpointer	  user_data)

{

  static guint handler_id = 0;

  GLogDomain *domain;

  GLogHandler *handler;

  g_return_val_if_fail ((log_levels & G_LOG_LEVEL_MASK) != 0, 0);

  g_return_val_if_fail (log_func != NULL, 0);

  if (!log_domain)

    log_domain = "";

  handler = g_new (GLogHandler, 1);

  g_mutex_lock (&g_messages_lock);

  domain = g_log_find_domain_L (log_domain);

  if (!domain)

    domain = g_log_domain_new_L (log_domain);

  handler->id = ++handler_id;

  handler->log_level = log_levels;

  handler->log_func = log_func;

  handler->data = user_data;

  handler->next = domain->handlers;

  domain->handlers = handler;

  g_mutex_unlock (&g_messages_lock);

  return handler_id;

}

/**

 * g_log_set_default_handler:

 * @log_func: the log handler function

 * @user_data: data passed to the log handler

 *

 * Installs a default log handler which is used if no

 * log handler has been set for the particular log domain

 * and log level combination. By default, GLib uses

 * g_log_default_handler() as default log handler.

 *

 * Returns: the previous default log handler

 *

 * Since: 2.6

 */

GLogFunc

g_log_set_default_handler (GLogFunc log_func,

			   gpointer user_data)

{

  GLogFunc old_log_func;

  g_mutex_lock (&g_messages_lock);

  old_log_func = default_log_func;

  default_log_func = log_func;

  default_log_data = user_data;

  g_mutex_unlock (&g_messages_lock);

  return old_log_func;

}

/**

 * g_test_log_set_fatal_handler:

 * @log_func: the log handler function.

 * @user_data: data passed to the log handler.

 *

 * Installs a non-error fatal log handler which can be

 * used to decide whether log messages which are counted

 * as fatal abort the program.

 *

 * The use case here is that you are running a test case

 * that depends on particular libraries or circumstances

 * and cannot prevent certain known critical or warning

 * messages. So you install a handler that compares the

 * domain and message to precisely not abort in such a case.

 *

 * Note that the handler is reset at the beginning of

 * any test case, so you have to set it inside each test

 * function which needs the special behavior.

 *

 * This handler has no effect on g_error messages.

 *

 * Since: 2.22

 **/

void

g_test_log_set_fatal_handler (GTestLogFatalFunc log_func,

                              gpointer          user_data)

{

  g_mutex_lock (&g_messages_lock);

  fatal_log_func = log_func;

  fatal_log_data = user_data;

  g_mutex_unlock (&g_messages_lock);

}

/**

 * g_log_remove_handler:

 * @log_domain: the log domain

 * @handler_id: the id of the handler, which was returned

 *     in g_log_set_handler()

 *

 * Removes the log handler.

 */

void

g_log_remove_handler (const gchar *log_domain,

		      guint	   handler_id)

{

  register GLogDomain *domain;

  g_return_if_fail (handler_id > 0);

  if (!log_domain)

    log_domain = "";

  g_mutex_lock (&g_messages_lock);

  domain = g_log_find_domain_L (log_domain);

  if (domain)

    {

      GLogHandler *work, *last;

      last = NULL;

      work = domain->handlers;

      while (work)

	{

	  if (work->id == handler_id)

	    {

	      if (last)

		last->next = work->next;

	      else

		domain->handlers = work->next;

	      g_log_domain_check_free_L (domain); 

	      g_mutex_unlock (&g_messages_lock);

	      g_free (work);

	      return;

	    }

	  last = work;

	  work = last->next;

	}

    } 

  g_mutex_unlock (&g_messages_lock);

  g_warning ("%s: could not find handler with id `%d' for domain \"%s\"",

	     G_STRLOC, handler_id, log_domain);

}

/**

 * g_logv:

 * @log_domain: the log domain

 * @log_level: the log level

 * @format: the message format. See the printf() documentation

 * @args: the parameters to insert into the format string

 *

 * Logs an error or debugging message.

 *

 * If the log level has been set as fatal, the abort()

 * function is called to terminate the program.

 */

void

g_logv (const gchar   *log_domain,

	GLogLevelFlags log_level,

	const gchar   *format,

	va_list	       args1)

{

  gboolean was_fatal = (log_level & G_LOG_FLAG_FATAL) != 0;

  gboolean was_recursion = (log_level & G_LOG_FLAG_RECURSION) != 0;

  gint i;

  log_level &= G_LOG_LEVEL_MASK;

  if (!log_level)

    return;

  for (i = g_bit_nth_msf (log_level, -1); i >= 0; i = g_bit_nth_msf (log_level, i))

    {

      register GLogLevelFlags test_level;

      test_level = 1 << i;

      if (log_level & test_level)

	{

	  GLogDomain *domain;

	  GLogFunc log_func;

	  GLogLevelFlags domain_fatal_mask;

	  gpointer data = NULL;

          gboolean masquerade_fatal = FALSE;

          guint depth;

	  if (was_fatal)

	    test_level |= G_LOG_FLAG_FATAL;

	  if (was_recursion)

	    test_level |= G_LOG_FLAG_RECURSION;

	  /* check recursion and lookup handler */

	  g_mutex_lock (&g_messages_lock);

          depth = GPOINTER_TO_UINT (g_private_get (&g_log_depth));

	  domain = g_log_find_domain_L (log_domain ? log_domain : "");

	  if (depth)

	    test_level |= G_LOG_FLAG_RECURSION;

	  depth++;

	  domain_fatal_mask = domain ? domain->fatal_mask : G_LOG_FATAL_MASK;

	  if ((domain_fatal_mask | g_log_always_fatal) & test_level)

	    test_level |= G_LOG_FLAG_FATAL;

	  if (test_level & G_LOG_FLAG_RECURSION)

	    log_func = _g_log_fallback_handler;

	  else

	    log_func = g_log_domain_get_handler_L (domain, test_level, &data);

	  domain = NULL;

	  g_mutex_unlock (&g_messages_lock);

	  g_private_set (&g_log_depth, GUINT_TO_POINTER (depth));

	  if (test_level & G_LOG_FLAG_RECURSION)

	    {

	      /* we use a stack buffer of fixed size, since we're likely

	       * in an out-of-memory situation

	       */

	      gchar buffer[1025];

              gsize size G_GNUC_UNUSED;

              va_list args2;

              G_VA_COPY (args2, args1);

	      size = _g_vsnprintf (buffer, 1024, format, args2);

              va_end (args2);

	      log_func (log_domain, test_level, buffer, data);

	    }

	  else

	    {

	      gchar *msg;

              va_list args2;

              G_VA_COPY (args2, args1);

              msg = g_strdup_vprintf (format, args2);

              va_end (args2);

	      log_func (log_domain, test_level, msg, data);

              if ((test_level & G_LOG_FLAG_FATAL)

                && !(test_level & G_LOG_LEVEL_ERROR))

                {

                  masquerade_fatal = fatal_log_func

                    && !fatal_log_func (log_domain, test_level, msg, fatal_log_data);

                }

	      g_free (msg);

	    }

	  if ((test_level & G_LOG_FLAG_FATAL) && !masquerade_fatal)

            {

#ifdef G_OS_WIN32

	      gchar *locale_msg = g_locale_from_utf8 (fatal_msg_buf, -1, NULL, NULL, NULL);

	      MessageBox (NULL, locale_msg, NULL,

			  MB_ICONERROR|MB_SETFOREGROUND);

	      if (IsDebuggerPresent () && !(test_level & G_LOG_FLAG_RECURSION))

		G_BREAKPOINT ();

	      else

		abort ();

#else

	      if (!(test_level & G_LOG_FLAG_RECURSION))

		G_BREAKPOINT ();

	      else

		abort ();

#endif /* !G_OS_WIN32 */

	    }

	  depth--;

	  g_private_set (&g_log_depth, GUINT_TO_POINTER (depth));

	}

    }

}

/**

 * g_log:

 * @log_domain: the log domain, usually #G_LOG_DOMAIN

 * @log_level: the log level, either from #GLogLevelFlags

 *     or a user-defined level

 * @format: the message format. See the printf() documentation

 * @...: the parameters to insert into the format string

 *

 * Logs an error or debugging message.

 *

 * If the log level has been set as fatal, the abort()

 * function is called to terminate the program.

 */

void

g_log (const gchar   *log_domain,

       GLogLevelFlags log_level,

       const gchar   *format,

       ...)

{

  va_list args;

  va_start (args, format);

  g_logv (log_domain, log_level, format, args);

  va_end (args);

}

void

g_return_if_fail_warning (const char *log_domain,

			  const char *pretty_function,

			  const char *expression)

{

  g_log (log_domain,

	 G_LOG_LEVEL_CRITICAL,

	 "%s: assertion `%s' failed",

	 pretty_function,

	 expression);

}

void

g_warn_message (const char     *domain,

                const char     *file,

                int             line,

                const char     *func,

                const char     *warnexpr)

{

  char *s, lstr[32];

  g_snprintf (lstr, 32, "%d", line);

  if (warnexpr)

    s = g_strconcat ("(", file, ":", lstr, "):",

                     func, func[0] ? ":" : "",

                     " runtime check failed: (", warnexpr, ")", NULL);

  else

    s = g_strconcat ("(", file, ":", lstr, "):",

                     func, func[0] ? ":" : "",

                     " ", "code should not be reached", NULL);

  g_log (domain, G_LOG_LEVEL_WARNING, "%s", s);

  g_free (s);

}

void

g_assert_warning (const char *log_domain,

		  const char *file,

		  const int   line,

		  const char *pretty_function,

		  const char *expression)

{

  g_log (log_domain,

	 G_LOG_LEVEL_ERROR,

	 expression 

	 ? "file %s: line %d (%s): assertion failed: (%s)"

	 : "file %s: line %d (%s): should not be reached",

	 file, 

	 line, 

	 pretty_function,

	 expression);

  abort ();

}

#define CHAR_IS_SAFE(wc) (!((wc < 0x20 && wc != '\t' && wc != '\n' && wc != '\r') || \

			    (wc == 0x7f) || \

			    (wc >= 0x80 && wc < 0xa0)))

static gchar*

strdup_convert (const gchar *string,

		const gchar *charset)

{

  if (!g_utf8_validate (string, -1, NULL))

    {

      GString *gstring = g_string_new ("[Invalid UTF-8] ");

      guchar *p;

      for (p = (guchar *)string; *p; p++)

	{

	  if (CHAR_IS_SAFE(*p) &&

	      !(*p == '\r' && *(p + 1) != '\n') &&

	      *p < 0x80)

	    g_string_append_c (gstring, *p);

	  else

	    g_string_append_printf (gstring, "\\x%02x", (guint)(guchar)*p);

	}

      return g_string_free (gstring, FALSE);

    }

  else

    {

      GError *err = NULL;

      gchar *result = g_convert_with_fallback (string, -1, charset, "UTF-8", "?", NULL, NULL, &err;;

      if (result)

	return result;

      else