| // Copyright 1999, 2007 Google Inc. All Rights Reserved. |
| // Author: Ray Sidney and many others |
| // |
| // Defines the VLOG_IS_ON macro that controls the variable-verbosity |
| // conditional logging. |
| // |
| // It's used by VLOG and VLOG_IF in logging.h |
| // and by RAW_VLOG in raw_logging.h to trigger the logging. |
| // |
| // It can also be used directly e.g. like this: |
| // if (VLOG_IS_ON(2)) { |
| // // do some logging preparation and logging |
| // // that can't be accomplished e.g. via just VLOG(2) << ...; |
| // } |
| // |
| // The truth value that VLOG_IS_ON(level) returns is determined by |
| // the three verbosity level flags: |
| // --v=<n> Gives the default maximal active V-logging level; |
| // 0 is the default. |
| // Normally positive values are used for V-logging levels. |
| // --vmodule=<str> Gives the per-module maximal V-logging levels to override |
| // the value given by --v. |
| // E.g. "my_module=2,foo*=3" would change the logging level |
| // for all code in source files "my_module.*" and "foo*.*" |
| // ("-inl" suffixes are also disregarded for this matching). |
| // |
| // SetVLOGLevel helper function is provided to do limited dynamic control over |
| // V-logging by overriding the per-module settings given via --vmodule flag. |
| // |
| // CAVEAT: --vmodule functionality is not available in non gcc compilers. |
| // |
| |
| #ifndef BASE_VLOG_IS_ON_H_ |
| #define BASE_VLOG_IS_ON_H_ |
| |
| #include "glog/log_severity.h" |
| |
| #if defined(__GNUC__) |
| // We emit an anonymous static int* variable at every VLOG_IS_ON(n) site. |
| // (Normally) the first time every VLOG_IS_ON(n) site is hit, |
| // we determine what variable will dynamically control logging at this site: |
| // it's either FLAGS_v or an appropriate internal variable |
| // matching the current source file that represents results of |
| // parsing of --vmodule flag and/or SetVLOGLevel calls. |
| #define VLOG_IS_ON(verboselevel) \ |
| ({ static @ac_google_namespace@::int32* vlocal__ = &@ac_google_namespace@::kLogSiteUninitialized; \ |
| @ac_google_namespace@::int32 verbose_level__ = (verboselevel); \ |
| (*vlocal__ >= verbose_level__) && \ |
| ((vlocal__ != &@ac_google_namespace@::kLogSiteUninitialized) || \ |
| (@ac_google_namespace@::InitVLOG3__(&vlocal__, &FLAGS_v, \ |
| __FILE__, verbose_level__))); }) |
| #else |
| // GNU extensions not available, so we do not support --vmodule. |
| // Dynamic value of FLAGS_v always controls the logging level. |
| #define VLOG_IS_ON(verboselevel) (FLAGS_v >= (verboselevel)) |
| #endif |
| |
| // Set VLOG(_IS_ON) level for module_pattern to log_level. |
| // This lets us dynamically control what is normally set by the --vmodule flag. |
| // Returns the level that previously applied to module_pattern. |
| // NOTE: To change the log level for VLOG(_IS_ON) sites |
| // that have already executed after/during InitGoogleLogging, |
| // one needs to supply the exact --vmodule pattern that applied to them. |
| // (If no --vmodule pattern applied to them |
| // the value of FLAGS_v will continue to control them.) |
| extern int SetVLOGLevel(const char* module_pattern, int log_level); |
| |
| // Various declarations needed for VLOG_IS_ON above: ========================= |
| |
| // Special value used to indicate that a VLOG_IS_ON site has not been |
| // initialized. We make this a large value, so the common-case check |
| // of "*vlocal__ >= verbose_level__" in VLOG_IS_ON definition |
| // passes in such cases and InitVLOG3__ is then triggered. |
| extern @ac_google_namespace@::int32 kLogSiteUninitialized; |
| |
| // Helper routine which determines the logging info for a particalur VLOG site. |
| // site_flag is the address of the site-local pointer to the controlling |
| // verbosity level |
| // site_default is the default to use for *site_flag |
| // fname is the current source file name |
| // verbose_level is the argument to VLOG_IS_ON |
| // We will return the return value for VLOG_IS_ON |
| // and if possible set *site_flag appropriately. |
| extern bool InitVLOG3__(@ac_google_namespace@::int32** site_flag, |
| @ac_google_namespace@::int32* site_default, |
| const char* fname, |
| @ac_google_namespace@::int32 verbose_level); |
| |
| #endif // BASE_VLOG_IS_ON_H_ |