glib/gmessages.h

   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, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  20  * file for a list of people on the GLib Team.  See the ChangeLog
  21  * files for a list of changes.  These files are distributed with
  22  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  23  */
  24
  25 #ifndef __G_MESSAGES_H__
  26 #define __G_MESSAGES_H__
  27
  28 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
  29 #error "Only <glib.h> can be included directly."
  30 #endif
  31
  32 #include <stdarg.h>
  33 #include <glib/gtypes.h>
  34 #include <glib/gmacros.h>
  35
  36 /* Suppress warnings when GCC is in -pedantic mode and not -std=c99
  37  */
  38 #if (__GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96))
  39 #pragma GCC system_header
  40 #endif
  41
  42 G_BEGIN_DECLS
  43
  44 /* calculate a string size, guaranteed to fit format + args.
  45  */
  46 GLIB_AVAILABLE_IN_ALL
  47 gsize   g_printf_string_upper_bound (const gchar* format,
  48                                      va_list      args) G_GNUC_PRINTF(1, 0);
  49
  50 /* Log level shift offset for user defined
  51  * log levels (0-7 are used by GLib).
  52  */
  53 #define G_LOG_LEVEL_USER_SHIFT  (8)
  54
  55 /* Glib log levels and flags.
  56  */
  57 typedef enum
  58 {
  59   /* log flags */
  60   G_LOG_FLAG_RECURSION          = 1 << 0,
  61   G_LOG_FLAG_FATAL              = 1 << 1,
  62
  63   /* GLib log levels */
  64   G_LOG_LEVEL_ERROR             = 1 << 2,       /* always fatal */
  65   G_LOG_LEVEL_CRITICAL          = 1 << 3,
  66   G_LOG_LEVEL_WARNING           = 1 << 4,
  67   G_LOG_LEVEL_MESSAGE           = 1 << 5,
  68   G_LOG_LEVEL_INFO              = 1 << 6,
  69   G_LOG_LEVEL_DEBUG             = 1 << 7,
  70
  71   G_LOG_LEVEL_MASK              = ~(G_LOG_FLAG_RECURSION | G_LOG_FLAG_FATAL)
  72 } GLogLevelFlags;
  73
  74 /* GLib log levels that are considered fatal by default */
  75 #define G_LOG_FATAL_MASK        (G_LOG_FLAG_RECURSION | G_LOG_LEVEL_ERROR)
  76
  77 typedef void            (*GLogFunc)             (const gchar   *log_domain,
  78                                                  GLogLevelFlags log_level,
  79                                                  const gchar   *message,
  80                                                  gpointer       user_data);
  81
  82 /* Logging mechanism
  83  */
  84 GLIB_AVAILABLE_IN_ALL
  85 guint           g_log_set_handler       (const gchar    *log_domain,
  86                                          GLogLevelFlags  log_levels,
  87                                          GLogFunc        log_func,
  88                                          gpointer        user_data);
  89 GLIB_AVAILABLE_IN_ALL
  90 void            g_log_remove_handler    (const gchar    *log_domain,
  91                                          guint           handler_id);
  92 GLIB_AVAILABLE_IN_ALL
  93 void            g_log_default_handler   (const gchar    *log_domain,
  94                                          GLogLevelFlags  log_level,
  95                                          const gchar    *message,
  96                                          gpointer        unused_data);
  97 GLIB_AVAILABLE_IN_ALL
  98 GLogFunc        g_log_set_default_handler (GLogFunc      log_func,
  99                                            gpointer      user_data);
 100 GLIB_AVAILABLE_IN_ALL
 101 void            g_log                   (const gchar    *log_domain,
 102                                          GLogLevelFlags  log_level,
 103                                          const gchar    *format,
 104                                          ...) G_GNUC_PRINTF (3, 4);
 105 GLIB_AVAILABLE_IN_ALL
 106 void            g_logv                  (const gchar    *log_domain,
 107                                          GLogLevelFlags  log_level,
 108                                          const gchar    *format,
 109                                          va_list         args) G_GNUC_PRINTF(3, 0);
 110 GLIB_AVAILABLE_IN_ALL
 111 GLogLevelFlags  g_log_set_fatal_mask    (const gchar    *log_domain,
 112                                          GLogLevelFlags  fatal_mask);
 113 GLIB_AVAILABLE_IN_ALL
 114 GLogLevelFlags  g_log_set_always_fatal  (GLogLevelFlags  fatal_mask);
 115
 116 /* internal */
 117 void    _g_log_fallback_handler (const gchar   *log_domain,
 118                                                  GLogLevelFlags log_level,
 119                                                  const gchar   *message,
 120                                                  gpointer       unused_data);
 121
 122 /* Internal functions, used to implement the following macros */
 123 GLIB_AVAILABLE_IN_ALL
 124 void g_return_if_fail_warning (const char *log_domain,
 125                                const char *pretty_function,
 126                                const char *expression) G_ANALYZER_NORETURN;
 127 GLIB_AVAILABLE_IN_ALL
 128 void g_warn_message           (const char     *domain,
 129                                const char     *file,
 130                                int             line,
 131                                const char     *func,
 132                                const char     *warnexpr) G_ANALYZER_NORETURN;
 133 GLIB_DEPRECATED
 134 void g_assert_warning         (const char *log_domain,
 135                                const char *file,
 136                                const int   line,
 137                                const char *pretty_function,
 138                                const char *expression) G_GNUC_NORETURN;
 139
 140
 141 #ifndef G_LOG_DOMAIN
 142 #define G_LOG_DOMAIN    ((gchar*) 0)
 143 #endif  /* G_LOG_DOMAIN */
 144
 145 #if defined(G_HAVE_ISO_VARARGS) && !G_ANALYZER_ANALYZING
 146 /* for(;;) ; so that GCC knows that control doesn't go past g_error().
 147  * Put space before ending semicolon to avoid C++ build warnings.
 148  */
 149 #define g_error(...)  G_STMT_START {                 \
 150                         g_log (G_LOG_DOMAIN,         \
 151                                G_LOG_LEVEL_ERROR,    \
 152                                __VA_ARGS__);         \
 153                         for (;;) ;                   \
 154                       } G_STMT_END
 155
 156 #define g_message(...)  g_log (G_LOG_DOMAIN,         \
 157                                G_LOG_LEVEL_MESSAGE,  \
 158                                __VA_ARGS__)
 159 #define g_critical(...) g_log (G_LOG_DOMAIN,         \
 160                                G_LOG_LEVEL_CRITICAL, \
 161                                __VA_ARGS__)
 162 #define g_warning(...)  g_log (G_LOG_DOMAIN,         \
 163                                G_LOG_LEVEL_WARNING,  \
 164                                __VA_ARGS__)
 165 #define g_info(...)     g_log (G_LOG_DOMAIN,         \
 166                                G_LOG_LEVEL_INFO,     \
 167                                __VA_ARGS__)
 168 #define g_debug(...)    g_log (G_LOG_DOMAIN,         \
 169                                G_LOG_LEVEL_DEBUG,    \
 170                                __VA_ARGS__)
 171 #elif defined(G_HAVE_GNUC_VARARGS)  && !G_ANALYZER_ANALYZING
 172 #define g_error(format...)    G_STMT_START {                 \
 173                                 g_log (G_LOG_DOMAIN,         \
 174                                        G_LOG_LEVEL_ERROR,    \
 175                                        format);              \
 176                                 for (;;) ;                   \
 177                               } G_STMT_END
 178
 179 #define g_message(format...)    g_log (G_LOG_DOMAIN,         \
 180                                        G_LOG_LEVEL_MESSAGE,  \
 181                                        format)
 182 #define g_critical(format...)   g_log (G_LOG_DOMAIN,         \
 183                                        G_LOG_LEVEL_CRITICAL, \
 184                                        format)
 185 #define g_warning(format...)    g_log (G_LOG_DOMAIN,         \
 186                                        G_LOG_LEVEL_WARNING,  \
 187                                        format)
 188 #define g_info(format...)       g_log (G_LOG_DOMAIN,         \
 189                                        G_LOG_LEVEL_INFO,     \
 190                                        format)
 191 #define g_debug(format...)      g_log (G_LOG_DOMAIN,         \
 192                                        G_LOG_LEVEL_DEBUG,    \
 193                                        format)
 194 #else   /* no varargs macros */
 195 static void g_error (const gchar *format, ...) G_ANALYZER_NORETURN;
 196 static void g_critical (const gchar *format, ...) G_ANALYZER_NORETURN;
 197
 198 static void
 199 g_error (const gchar *format,
 200          ...)
 201 {
 202   va_list args;
 203   va_start (args, format);
 204   g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_ERROR, format, args);
 205   va_end (args);
 206
 207   for(;;) ;
 208 }
 209 static void
 210 g_message (const gchar *format,
 211            ...)
 212 {
 213   va_list args;
 214   va_start (args, format);
 215   g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_MESSAGE, format, args);
 216   va_end (args);
 217 }
 218 static void
 219 g_critical (const gchar *format,
 220             ...)
 221 {
 222   va_list args;
 223   va_start (args, format);
 224   g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_CRITICAL, format, args);
 225   va_end (args);
 226 }
 227 static void
 228 g_warning (const gchar *format,
 229            ...)
 230 {
 231   va_list args;
 232   va_start (args, format);
 233   g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_WARNING, format, args);
 234   va_end (args);
 235 }
 236 static void
 237 g_info (const gchar *format,
 238         ...)
 239 {
 240   va_list args;
 241   va_start (args, format);
 242   g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_INFO, format, args);
 243   va_end (args);
 244 }
 245 static void
 246 g_debug (const gchar *format,
 247          ...)
 248 {
 249   va_list args;
 250   va_start (args, format);
 251   g_logv (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, format, args);
 252   va_end (args);
 253 }
 254 #endif  /* !__GNUC__ */
 255
 256 /**
 257  * GPrintFunc:
 258  * @string: the message to output
 259  *
 260  * Specifies the type of the print handler functions.
 261  * These are called with the complete formatted string to output.
 262  */
 263 typedef void    (*GPrintFunc)           (const gchar    *string);
 264 GLIB_AVAILABLE_IN_ALL
 265 void            g_print                 (const gchar    *format,
 266                                          ...) G_GNUC_PRINTF (1, 2);
 267 GLIB_AVAILABLE_IN_ALL
 268 GPrintFunc      g_set_print_handler     (GPrintFunc      func);
 269 GLIB_AVAILABLE_IN_ALL
 270 void            g_printerr              (const gchar    *format,
 271                                          ...) G_GNUC_PRINTF (1, 2);
 272 GLIB_AVAILABLE_IN_ALL
 273 GPrintFunc      g_set_printerr_handler  (GPrintFunc      func);
 274
 275 /**
 276  * g_warn_if_reached:
 277  *
 278  * Logs a critical warning.
 279  *
 280  * Since: 2.16
 281  */
 282 #define g_warn_if_reached() \
 283   do { \
 284     g_warn_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, NULL); \
 285   } while (0)
 286
 287 /**
 288  * g_warn_if_fail:
 289  * @expr: the expression to check
 290  *
 291  * Logs a warning if the expression is not true.
 292  *
 293  * Since: 2.16
 294  */
 295 #define g_warn_if_fail(expr) \
 296   do { \
 297     if G_LIKELY (expr) ; \
 298     else g_warn_message (G_LOG_DOMAIN, __FILE__, __LINE__, G_STRFUNC, #expr); \
 299   } while (0)
 300
 301 #ifdef G_DISABLE_CHECKS
 302
 303 /**
 304  * g_return_if_fail:
 305  * @expr: the expression to check
 306  *
 307  * Verifies that the expression @expr, usually representing a precondition,
 308  * evaluates to %TRUE. If the function returns a value, use
 309  * g_return_val_if_fail() instead.
 310  *
 311  * If @expr evaluates to %FALSE, the current function should be considered to
 312  * have undefined behaviour (a programmer error). The only correct solution
 313  * to such an error is to change the module that is calling the current
 314  * function, so that it avoids this incorrect call.
 315  *
 316  * To make this undefined behaviour visible, if @expr evaluates to %FALSE,
 317  * the result is usually that a critical message is logged and the current
 318  * function returns.
 319  *
 320  * If G_DISABLE_CHECKS is defined then the check is not performed.  You
 321  * should therefore not depend on any side effects of @expr.
 322  */
 323 #define g_return_if_fail(expr) G_STMT_START{ (void)0; }G_STMT_END
 324
 325 /**
 326  * g_return_val_if_fail:
 327  * @expr: the expression to check
 328  * @val: the value to return from the current function
 329  *       if the expression is not true
 330  *
 331  * Verifies that the expression @expr, usually representing a precondition,
 332  * evaluates to %TRUE. If the function does not return a value, use
 333  * g_return_if_fail() instead.
 334  *
 335  * If @expr evaluates to %FALSE, the current function should be considered to
 336  * have undefined behaviour (a programmer error). The only correct solution
 337  * to such an error is to change the module that is calling the current
 338  * function, so that it avoids this incorrect call.
 339  *
 340  * To make this undefined behaviour visible, if @expr evaluates to %FALSE,
 341  * the result is usually that a critical message is logged and @val is
 342  * returned from the current function.
 343  *
 344  * If G_DISABLE_CHECKS is defined then the check is not performed.  You
 345  * should therefore not depend on any side effects of @expr.
 346  */
 347 #define g_return_val_if_fail(expr,val) G_STMT_START{ (void)0; }G_STMT_END
 348
 349 /**
 350  * g_return_if_reached:
 351  *
 352  * Logs a critical message and returns from the current function.
 353  * This can only be used in functions which do not return a value.
 354  */
 355 #define g_return_if_reached() G_STMT_START{ return; }G_STMT_END
 356
 357 /**
 358  * g_return_val_if_reached:
 359  * @val: the value to return from the current function
 360  *
 361  * Logs a critical message and returns @val.
 362  */
 363 #define g_return_val_if_reached(val) G_STMT_START{ return (val); }G_STMT_END
 364
 365 #else /* !G_DISABLE_CHECKS */
 366
 367 #define g_return_if_fail(expr)          G_STMT_START{                   \
 368      if G_LIKELY(expr) { } else                                         \
 369        {                                                                \
 370          g_return_if_fail_warning (G_LOG_DOMAIN,                        \
 371                                    G_STRFUNC,                           \
 372                                    #expr);                              \
 373          return;                                                        \
 374        };                               }G_STMT_END
 375
 376 #define g_return_val_if_fail(expr,val)  G_STMT_START{                   \
 377      if G_LIKELY(expr) { } else                                         \
 378        {                                                                \
 379          g_return_if_fail_warning (G_LOG_DOMAIN,                        \
 380                                    G_STRFUNC,                           \
 381                                    #expr);                              \
 382          return (val);                                                  \
 383        };                               }G_STMT_END
 384
 385 #define g_return_if_reached()           G_STMT_START{                   \
 386      g_log (G_LOG_DOMAIN,                                               \
 387             G_LOG_LEVEL_CRITICAL,                                       \
 388             "file %s: line %d (%s): should not be reached",             \
 389             __FILE__,                                                   \
 390             __LINE__,                                                   \
 391             G_STRFUNC);                                                 \
 392      return;                            }G_STMT_END
 393
 394 #define g_return_val_if_reached(val)    G_STMT_START{                   \
 395      g_log (G_LOG_DOMAIN,                                               \
 396             G_LOG_LEVEL_CRITICAL,                                       \
 397             "file %s: line %d (%s): should not be reached",             \
 398             __FILE__,                                                   \
 399             __LINE__,                                                   \
 400             G_STRFUNC);                                                 \
 401      return (val);                      }G_STMT_END
 402
 403 #endif /* !G_DISABLE_CHECKS */
 404
 405 G_END_DECLS
 406
 407 #endif /* __G_MESSAGES_H__ */