gerror.c

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GLib Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 #include "glib.h"
  28
  29 static GError*
  30 g_error_new_valist(GQuark         domain,
  31                    gint           code,
  32                    const gchar   *format,
  33                    va_list        args)
  34 {
  35   GError *error;
  36
  37   error = g_new (GError, 1);
  38
  39   error->domain = domain;
  40   error->code = code;
  41   error->message = g_strdup_vprintf (format, args);
  42
  43   return error;
  44 }
  45
  46 /**
  47  * g_error_new:
  48  * @domain: error domain
  49  * @code: error code
  50  * @format: printf()-style format for error message
  51  * @Varargs: parameters for message format
  52  *
  53  * Creates a new #GError with the given @domain and @code,
  54  * and a message formatted with @format.
  55  *
  56  * Return value: a new #GError
  57  **/
  58 GError*
  59 g_error_new (GQuark       domain,
  60              gint         code,
  61              const gchar *format,
  62              ...)
  63 {
  64   GError* error;
  65   va_list args;
  66
  67   g_return_val_if_fail (format != NULL, NULL);
  68   g_return_val_if_fail (domain != 0, NULL);
  69
  70   va_start (args, format);
  71   error = g_error_new_valist (domain, code, format, args);
  72   va_end (args);
  73
  74   return error;
  75 }
  76
  77 /**
  78  * g_error_new_literal:
  79  * @domain: error domain
  80  * @code: error code
  81  * @message: error message
  82  *
  83  * Creates a new #GError; unlike g_error_new(), @message is not
  84  * a printf()-style format string. Use this function if @message
  85  * contains text you don't have control over, that could include
  86  * printf() escape sequences.
  87  *
  88  * Return value: a new #GError
  89  **/
  90 GError*
  91 g_error_new_literal (GQuark         domain,
  92                      gint           code,
  93                      const gchar   *message)
  94 {
  95   GError* err;
  96
  97   g_return_val_if_fail (message != NULL, NULL);
  98   g_return_val_if_fail (domain != 0, NULL);
  99
 100   err = g_new (GError, 1);
 101
 102   err->domain = domain;
 103   err->code = code;
 104   err->message = g_strdup (message);
 105
 106   return err;
 107 }
 108
 109 /**
 110  * g_error_free:
 111  * @error: a #GError
 112  *
 113  * Frees a #GError and associated resources.
 114  *
 115  **/
 116 void
 117 g_error_free (GError *error)
 118 {
 119   g_return_if_fail (error != NULL);
 120
 121   g_free (error->message);
 122
 123   g_free (error);
 124 }
 125
 126 /**
 127  * g_error_copy:
 128  * @error: a #GError
 129  *
 130  * Makes a copy of @error.
 131  *
 132  * Return value: a new #GError
 133  **/
 134 GError*
 135 g_error_copy (const GError *error)
 136 {
 137   GError *copy;
 138
 139   g_return_val_if_fail (error != NULL, NULL);
 140
 141   copy = g_new (GError, 1);
 142
 143   *copy = *error;
 144
 145   copy->message = g_strdup (error->message);
 146
 147   return copy;
 148 }
 149
 150 /**
 151  * g_error_matches:
 152  * @error: a #GError
 153  * @domain: an error domain
 154  * @code: an error code
 155  *
 156  * Returns TRUE if @error matches @domain and @code, FALSE
 157  * otherwise.
 158  *
 159  * Return value: whether @error has @domain and @code
 160  **/
 161 gboolean
 162 g_error_matches (const GError *error,
 163                  GQuark        domain,
 164                  gint          code)
 165 {
 166   return error &&
 167     error->domain == domain &&
 168     error->code == code;
 169 }
 170
 171 #define ERROR_OVERWRITTEN_WARNING "GError set over the top of a previous GError or uninitialized memory.\n" \
 172                "This indicates a bug in someone's code. You must ensure an error is NULL before it's set.\n" \
 173                "The overwriting error message was: %s"
 174
 175 /**
 176  * g_set_error:
 177  * @err: a return location for a #GError, or NULL
 178  * @domain: error domain
 179  * @code: error code
 180  * @format: printf()-style format
 181  * @Varargs: args for @format
 182  *
 183  * Does nothing if @err is NULL; if @err is non-NULL, then *@err must
 184  * be NULL. A new #GError is created and assigned to *@err.
 185  **/
 186 void
 187 g_set_error (GError      **err,
 188              GQuark        domain,
 189              gint          code,
 190              const gchar  *format,
 191              ...)
 192 {
 193   GError *new;
 194
 195   va_list args;
 196
 197   if (err == NULL)
 198     return;
 199
 200   va_start (args, format);
 201   new = g_error_new_valist (domain, code, format, args);
 202   va_end (args);
 203
 204   if (*err == NULL)
 205     *err = new;
 206   else
 207     g_warning (ERROR_OVERWRITTEN_WARNING, new->message);
 208 }
 209
 210 /**
 211  * g_propagate_error:
 212  * @dest: error return location
 213  * @src: error to move into the return location
 214  *
 215  * If @dest is NULL, free @src; otherwise,
 216  * moves @src into *@dest. *@dest must be NULL.
 217  **/
 218 void
 219 g_propagate_error (GError       **dest,
 220                    GError        *src)
 221 {
 222   g_return_if_fail (src != NULL);
 223
 224   if (dest == NULL)
 225     {
 226       if (src)
 227         g_error_free (src);
 228       return;
 229     }
 230   else
 231     {
 232       if (*dest != NULL)
 233         g_warning (ERROR_OVERWRITTEN_WARNING, src->message);
 234       else
 235         *dest = src;
 236     }
 237 }
 238
 239 /**
 240  * g_clear_error:
 241  * @err: a #GError return location
 242  *
 243  * If @err is NULL, does nothing. If @err is non-NULL,
 244  * calls g_error_free() on *@err and sets *@err to NULL.
 245  **/
 246 void
 247 g_clear_error (GError **err)
 248 {
 249   if (err && *err)
 250     {
 251       g_error_free (*err);
 252       *err = NULL;
 253     }
 254 }