le_log.h

    1 /**
    2  * @page c_logging Logging API
    3  *
    4  * @subpage le_log.h "API Reference" <br>
    5  *
    6  * The Legato Logging API provides a toolkit allowing code to be instrumented with error, warning,
    7  * informational, and debugging messages. These messages can be turned on or off remotely and pushed or pulled
    8  * from the device through a secure shell, cloud services interfaces, e-mail, SMS, etc.
    9  *
   10  * @section c_log_logging Logging Basics
   11  *
   12  * Legato's logging can be configured through this API, and there's also a command-line target
   13  * @ref toolsTarget_log tool available.
   14  *
   15  * @subsection c_log_levels Levels
   16  *
   17  * Log messages are categorized according to the severity of the information being logged.
   18  * A log message may be purely informational, describing something that is
   19  * expected to occur from time-to-time during normal operation; or it may be a report of a fault
   20  * that might have a significant negative impact on the operation of the system.  To
   21  * differentiate these, each log entry is associated with one of the following log levels:
   22  *
   23  *  - @ref LE_LOG_DEBUG "DEBUG":
   24  *    Handy for troubleshooting.
   25  *  - @ref LE_LOG_INFO "INFORMATION":
   26  *    Expected to happen; can be interesting even when not troubleshooting.
   27  *  - @ref LE_LOG_WARN "WARNING":
   28  *    Should not normally happen; may not have any real impact on system performance.
   29  *  - @ref LE_LOG_ERR "ERROR":
   30  *    Fault that may result in noticeable short-term system misbehaviour. Needs attention.
   31  *  - @ref LE_LOG_CRIT "CRITICAL":
   32  *    Fault needs urgent attention. Will likely result in system failure.
   33  *  - @ref LE_LOG_EMERG "EMERGENCY":
   34  *    Definite system failure.
   35  *
   36  * @subsection c_log_basic_defaultSyslog Standard Out and Standard Error in Syslog
   37  *
   38  * By default, app processes will have their @c stdout and @c stderr redirected to the @c syslog. Each
   39  * process’s stdout will be logged at INFO severity level; it’s stderr will be logged at
   40  * “ERR” severity level.
   41 
   42  * There are two limitations with this feature:
   43  * - the PID reported in the logs generally refer to the PID of the process that
   44  * generates the stdout/stderr message. If a process forks, then both the parent and
   45  * child processes’ stdout/stderr will share the same connection to the syslog, and the parent’s
   46  * PID will be reported in the logs for both processes.
   47  * - stdout is line buffered when connected to a terminal, which means
   48  * <code>printf(“hello\n”)</code> will be printed to the terminal immediately. If stdout is
   49  * connected to something like a pipe it's bulk buffered, which means a flush doesn't occur until the buffer is full.
   50  *
   51  * To make your process line buffer stdout so that printf will show up in the logs as expected,
   52  * the @c setlinebuf(stdout) system call can be used.  Alternatively, @c fflush(stdout) can be called \
   53  * to force a flush of the stdout buffer.
   54  *
   55  * This issue doesn't exist with stderr as stderr is never buffered.
   56  *
   57  * @subsection c_log_basic_logging Basic Logging
   58  *
   59  * A series of macros are available to make logging easy.
   60  *
   61  * None of them return anything.
   62  *
   63  * All of them accept printf-style arguments, consisting of a format string followed by zero or more
   64  * parameters to be printed (depending on the contents of the format string).
   65  *
   66  * There is a logging macro for each of the log levels:
   67  *
   68  *  - @ref LE_DEBUG(formatString, ...)
   69  *  - @ref LE_INFO(formatString, ...)
   70  *  - @ref LE_WARN(formatString, ...)
   71  *  - @ref LE_ERROR(formatString, ...)
   72  *  - @ref LE_CRIT(formatString, ...)
   73  *  - @ref LE_EMERG(formatString, ...)
   74  *
   75  * For example,
   76  * @code
   77  * LE_INFO("Obtained new IP address %s.", ipAddrStr);
   78  * @endcode
   79  *
   80  * @subsection c_log_conditional_logging Conditional Logging
   81  *
   82  * Similar to the basic macros, but these contain a conditional expression as their first parameter.  If this expression equals
   83  * true, then the macro will generate this log output:
   84  *
   85  *  - @ref LE_DEBUG_IF(expression, formatString, ...)
   86  *  - @ref LE_INFO_IF(expression, formatString, ...)
   87  *  - @ref LE_WARN_IF(expression, formatString, ...)
   88  *  - @ref LE_ERROR_IF(expression, formatString, ...)
   89  *  - @ref LE_CRIT_IF(expression, formatString, ...)
   90  *  - @ref LE_EMERG_IF(expression, formatString, ...)
   91  *
   92  * Instead of writing
   93  * @code
   94  * if (result == -1)
   95  * {
   96  *     LE_WARN("Failed to send message to server.  Errno = %d.", errno);
   97  * }
   98  * @endcode
   99  *
  100  * you could write this:
  101  * @code
  102  * LE_WARN_IF(result == -1, "Failed to send message to server.  Errno = %d.", errno);
  103  * @endcode
  104  *
  105  * @subsection c_log_loging_fatals Fatal Errors
  106  *
  107  * There are some special logging macros intended for fatal errors:
  108  *
  109  *  - @ref LE_FATAL(formatString, ...) \n
  110  *    Always kills the calling process after logging the message at EMERGENCY level (never returns).
  111  *  - @ref LE_FATAL_IF(condition, formatString, ...) \n
  112  *    If the condition is true, kills the calling process after logging the message at EMERGENCY
  113  *    level.
  114  *  - @ref LE_ASSERT(condition) \n
  115  *    If the condition is true, does nothing. If the condition is false, logs the source
  116  *    code text of the condition at EMERGENCY level and kills the calling process.
  117  *  - @ref LE_ASSERT_OK(condition) \n
  118  *    If the condition is LE_OK (0), does nothing. If the condition is anything else, logs the
  119  *    a message at EMERGENCY level, containing the source code text of the condition, indicating
  120  *    that it did not evaluate to LE_OK, and kills the calling process.
  121  *
  122  * For example,
  123  * @code
  124  * if (NULL == objPtr)
  125  * {
  126  *     LE_FATAL("Object pointer is NULL!");
  127  * }
  128  *
  129  * // Now I can go ahead and use objPtr, knowing that if it was NULL then LE_FATAL() would have
  130  * // been called and LE_FATAL() never returns.
  131  * @endcode
  132  *
  133  * or,
  134  *
  135  * @code
  136  * LE_FATAL_IF(NULL == objPtr, "Object pointer is NULL!");
  137  *
  138  * // Now I can go ahead and use objPtr, knowing that if it was NULL then LE_FATAL_IF() would not
  139  * // have returned.
  140  * @endcode
  141  *
  142  * or,
  143  *
  144  * @code
  145  * LE_ASSERT(NULL != objPtr);
  146  *
  147  * // Now I can go ahead and use objPtr, knowing that if it was NULL then LE_ASSERT() would not
  148  * // have returned.
  149  * @endcode
  150  *
  151  * @subsection c_log_tracing Tracing
  152  *
  153  * Finally, a macro is provided for tracing:
  154  *
  155  *  - @ref LE_TRACE(traceRef, string, ...)
  156  *
  157  * This macro is special because it's independent of log level.  Instead, trace messages are
  158  * associated with a trace keyword.  Tracing can be enabled and disabled based on these keywords.
  159  *
  160  * If a developer wanted to trace the creation of "shape"
  161  * objects in their GUI package, they could add trace statements like the following:
  162  *
  163  * @code
  164  * LE_TRACE(NewShapeTraceRef, "Created %p with position (%d,%d).", shapePtr, shapePtr->x, shapePtr->y);
  165  * @endcode
  166  *
  167  * The reference to the trace is obtained at start-up as follows:
  168  *
  169  * @code
  170  * NewShapeTraceRef = le_log_GetTraceRef("newShape");
  171  * @endcode
  172  *
  173  * This allows enabling and disabling these LE_TRACE() calls using the "newShape" keyword
  174  * through configuration settings and runtime log control tools.  See @ref c_log_controlling below.
  175  *
  176  * Applications can use @ref LE_IS_TRACE_ENABLED(NewShapeTraceRef) to query whether
  177  * a trace keyword is enabled.
  178  *
  179  * These allow apps to hook into the trace management system to use it to implement
  180  * sophisticated, app-specific tracing or profiling features.
  181  *
  182  * @subsection c_log_resultTxt Result Code Text
  183  *
  184  * The @ref le_result_t macro supports printing an error condition in a human-readable text string.
  185  *
  186  * @code
  187  * result = le_foo_DoSomething();
  188  *
  189  * if (result != LE_OK)
  190  * {
  191  *     LE_ERROR("Failed to do something. Result = %d (%s).", result, LE_RESULT_TXT(result));
  192  * }
  193  * @endcode
  194  *
  195  *
  196  * @section c_log_controlling Log Controls
  197  *
  198  * Log level filtering and tracing can be controlled at runtime using:
  199  *  - the command-line Log Control Tool (@ref toolsTarget_log)
  200  *  - configuration settings
  201  *  - environment variables
  202  *  - function calls.
  203  *
  204  * @subsection c_log_control_tool Log Control Tool
  205  *
  206  * The log control tool is used from the command-line to control the log
  207  * level filtering, log output location (syslog/stderr), and tracing for different components
  208  * within a running system.
  209  *
  210  * Online documentation can be accessed from the log control tool by running "log help".
  211  *
  212  * Here are some code samples.
  213  *
  214  * To set the log level to INFO for a component "myComp" running in all processes with the
  215  * name "myProc":
  216  * @verbatim
  217 $ log level INFO myProc/myComp
  218 @endverbatim
  219  *
  220  * To set the log level to DEBUG for a component "myComp" running in a process with PID 1234:
  221  * @verbatim
  222 $ log level DEBUG 1234/myComp
  223 @endverbatim
  224  *
  225  * To enable all LE_TRACE statements tagged with the keyword "foo" in a component called "myComp"
  226  * running in all processes called "myProc":
  227  * @verbatim
  228 $ log trace foo myProc/myComp
  229 @endverbatim
  230  *
  231  * To disable the trace statements tagged with "foo" in the component "myComp" in processes
  232  * called "myProc":
  233  * @verbatim
  234 $ log stoptrace foo myProc/myComp
  235 @endverbatim
  236  *
  237  * With all of the above examples "*" can be used in place of the process name or a component
  238  * name (or both) to mean "all processes" and/or "all components".
  239  *
  240  * @subsection c_log_control_config Log Control Configuration Settings
  241  *
  242  * @note The configuration settings haven't been implemented yet.
  243  *
  244  * @todo Write @ref c_log_control_config section.
  245  *
  246  * @subsection c_log_control_environment_vars Environment Variables
  247  *
  248  * Environment variables can be used to control the default log settings, taking effect immediately
  249  * at process start-up; even before the Log Control Daemon has been connected to.
  250  *
  251  * Settings in the Log Control Daemon (applied through configuration and/or the log control tool)
  252  * will override the environment variable settings when the process connects to the Log
  253  * Control Daemon.
  254  *
  255  * @subsubsection c_log_control_env_level LE_LOG_LEVEL
  256  *
  257  * @c LE_LOG_LEVEL can be used to set the default log filter level for all components
  258  * in the process.  Valid values are:
  259  *
  260  * - @c EMERGENCY
  261  * - @c CRITICAL
  262  * - @c ERROR
  263  * - @c WARNING
  264  * - @c INFO
  265  * - @c DEBUG
  266  *
  267  * For example,
  268  * @verbatim
  269 $ export LE_LOG_LEVEL=DEBUG
  270 @endverbatim
  271  *
  272  * @subsubsection c_log_control_env_trace LE_LOG_TRACE
  273  *
  274  * @c LE_LOG_TRACE allows trace keywords to be enabled by default.  The contents of this
  275  * variable is a colon-separated list of keywords that should be enabled. Each keyword
  276  * must be prefixed with a component name followed by a slash ('/').
  277  *
  278  * For example,
  279  * @verbatim
  280 $ export LE_LOG_TRACE=framework/fdMonitor:framework/logControl
  281 @endverbatim
  282  *
  283  * @subsection c_log_control_functions Programmatic Log Control
  284  *
  285  * Normally, configuration settings and the log control tool should suffice for controlling
  286  * logging functionality.  In some situations, it can be convenient
  287  * to control logging programmatically in C.
  288  *
  289  * le_log_SetFilterLevel() sets the log filter level.
  290  *
  291  * le_log_GetFilterLevel() gets the log filter level.
  292  *
  293  * Trace keywords can be enabled and disabled programmatically by calling
  294  * @subpage le_log_EnableTrace() and @ref le_log_DisableTrace().
  295  *
  296  *
  297  * @section c_log_format Log Formats
  298  *
  299  * Log entries can also contain any of these:
  300  *  - timestamp (century, year, month, day, hours, minutes, seconds, milliseconds, microseconds)
  301  *  - level (debug, info, warning, etc.) @b or trace keyword
  302  *  - process ID
  303  *  - component name
  304  *  - thread name
  305  *  - source code file name
  306  *  - function name
  307  *  - source code line number
  308  *
  309  * Log messages have the following format:
  310  *
  311  * @verbatim
  312 Jan  3 02:37:56  INFO  | processName[pid]/componentName T=threadName | fileName.c funcName() lineNum | Message
  313 @endverbatim
  314  *
  315  * @section c_log_debugFiles App Crash Logs
  316 
  317 * When a process within an app faults or exits in error, a copy of the current syslog buffer
  318 * is captured along with a core file of the process crash (if generated).
  319 
  320 * The core file maximum size is determined by the process settings @c maxCoreDumpFileBytes and
  321 * @c maxFileBytes found in the processes section of your app's @c .adef file.  By default, the
  322 * @c maxCoreDumpFileBytes is set to 0, do not create a core file.
  323 
  324 * To help save the target from flash burnout, the syslog and core files are stored in the RAM
  325 * FS under /tmp.  When a crash occurs, this directory is created:
  326 
  327  @verbatim
  328  /tmp/legato_logs/
  329  @endverbatim
  330 
  331 * The files in that directory look like this:
  332 
  333  @verbatim
  334  core-myProc-1418694851
  335  syslog-myApp-myProc-1418694851
  336  @endverbatim
  337 
  338 * To save on RAM space, only the most recent 4 copies of each file are preserved.
  339 
  340 * If the fault action for that app's process is to reboot the target, the output location is changed to
  341 * this (and the most recent files in RAM space are preserved across reboots):
  342 
  343  @verbatim
  344  /mnt/flash/legato_logs/
  345  @endverbatim
  346 
  347 *
  348  * @todo May need to support log format configuration through command-line arguments or a
  349  *       configuration file.
  350  *
  351  * @todo Write @ref c_log_retrieving section
  352  *
  353  * <HR>
  354  *
  355  * Copyright (C) Sierra Wireless Inc.
  356  */
  357 
  358 
  359 /** @file le_log.h
  360  *
  361  * Legato @ref c_logging include file.
  362  *
  363  * Copyright (C) Sierra Wireless Inc.
  364  */
  365 
  366 #ifndef LEGATO_LOG_INCLUDE_GUARD
  367 #define LEGATO_LOG_INCLUDE_GUARD
  368 
  369 //--------------------------------------------------------------------------------------------------
  370 /**
  371  * Local definitions that should not be used directly.
  372  */
  373 //--------------------------------------------------------------------------------------------------
  374 typedef enum _le_log_Level_t
  375 {
  376     LE_LOG_DEBUG,   ///< Debug message.
  377     LE_LOG_INFO,    ///< Informational message.  Normally expected.
  378     LE_LOG_WARN,    ///< Warning.  Possibly indicates a problem.  Should be addressed.
  379     LE_LOG_ERR,     ///< Error.  Definitely indicates a  fault that needs to be addressed.
  380                     ///  Possibly resulted in a system failure.
  381     LE_LOG_CRIT,    ///< Critical error.  Fault that almost certainly has or will result in a
  382                     ///  system failure.
  383     LE_LOG_EMERG    ///< Emergency.  A fatal error has occurred.  A process is being terminated.
  384 }
  385 le_log_Level_t;
  386 
  387 //--------------------------------------------------------------------------------------------------
  388 /**
  389  * Compile-time filtering level.
  390  *
  391  * @note Logs below this filter level will be removed at compile-time and cannot be enabled
  392  *       at runtime.
  393  */
  394 //--------------------------------------------------------------------------------------------------
  395 #if LE_CONFIG_LOG_STATIC_FILTER_EMERG
  396 #   define LE_LOG_LEVEL_STATIC_FILTER   LE_LOG_EMERG
  397 #elif LE_CONFIG_LOG_STATIC_FILTER_CRIT
  398 #   define LE_LOG_LEVEL_STATIC_FILTER   LE_LOG_CRIT
  399 #elif LE_CONFIG_LOG_STATIC_FILTER_ERR
  400 #   define LE_LOG_LEVEL_STATIC_FILTER   LE_LOG_ERR
  401 #elif LE_CONFIG_LOG_STATIC_FILTER_WARN
  402 #   define LE_LOG_LEVEL_STATIC_FILTER   LE_LOG_WARN
  403 #elif LE_CONFIG_LOG_STATIC_FILTER_INFO
  404 #   define LE_LOG_LEVEL_STATIC_FILTER   LE_LOG_INFO
  405 #else /* default to LE_DEBUG */
  406 #   define LE_LOG_LEVEL_STATIC_FILTER   LE_LOG_DEBUG
  407 #endif
  408 
  409 //--------------------------------------------------------------------------------------------------
  410 /// @cond HIDDEN_IN_USER_DOCS
  411 
  412 typedef struct le_log_Session* le_log_SessionRef_t;
  413 
  414 typedef struct le_log_Trace* le_log_TraceRef_t;
  415 
  416 #if !defined(LE_DEBUG) && \
  417     !defined(LE_DUMP) && \
  418     !defined(LE_LOG_DUMP) && \
  419     !defined(LE_INFO) && \
  420     !defined(LE_WARN) && \
  421     !defined(LE_ERROR) && \
  422     !defined(LE_CRIT) && \
  423     !defined(LE_EMERG)
  424 
  425 /// Default log implementation is in use.
  426 #   define LE_LOG_DEFAULT_IMPL 1
  427 
  428 //--------------------------------------------------------------------------------------------------
  429 /**
  430  * Send a message to the logging target.
  431  **/
  432 //--------------------------------------------------------------------------------------------------
  433 void _le_log_Send
  434 (
  435     const le_log_Level_t     level,             ///< Log level.
  436     const le_log_TraceRef_t  traceRef,          ///< Trace reference.  May be NULL.
  437     le_log_SessionRef_t      logSession,        ///< Log session.  May be NULL.
  438     const char              *filenamePtr,       ///< File name.
  439     const char              *functionNamePtr,   ///< Function name.  May be NULL.
  440     const unsigned int       lineNumber,        ///< Line number.
  441     const char              *formatPtr,         ///< Format string.
  442     ...                                         ///< Positional parameters.
  443 ) __attribute__((format (printf, 7, 8)));
  444 
  445 //--------------------------------------------------------------------------------------------------
  446 /**
  447  * Log data block.  Provides a hex dump for debug.
  448  */
  449 //--------------------------------------------------------------------------------------------------
  450 void _le_LogData
  451 (
  452     le_log_Level_t       level,             ///< Log level.
  453     const uint8_t       *dataPtr,           ///< The buffer address to be dumped.
  454     int                  dataLength,        ///< The data length of buffer.
  455     const char          *filenamePtr,       ///< The name of the source file that logged the
  456                                             ///< message.
  457     const char          *functionNamePtr,   ///< The name of the function that logged the message.
  458     const unsigned int   lineNumber         ///< The line number in the source file that logged the
  459                                             ///< message.
  460 );
  461 
  462 //--------------------------------------------------------------------------------------------------
  463 /**
  464  * Gets a reference to a trace keyword's settings.
  465  *
  466  * @return  Trace reference.
  467  **/
  468 //--------------------------------------------------------------------------------------------------
  469 le_log_TraceRef_t _le_log_GetTraceRef
  470 (
  471     le_log_SessionRef_t  logSession,    ///< Log session.
  472     const char          *keyword        ///< Trace keyword.
  473 );
  474 
  475 //--------------------------------------------------------------------------------------------------
  476 /**
  477  * Sets the log filter level for the calling component.
  478  **/
  479 //--------------------------------------------------------------------------------------------------
  480 void _le_log_SetFilterLevel
  481 (
  482     le_log_SessionRef_t logSession, ///< Log session.
  483     le_log_Level_t      level       ///< Log level to apply.
  484 );
  485 
  486 //--------------------------------------------------------------------------------------------------
  487 /**
  488  * Filtering session reference for the current source file.
  489  *
  490  * @note The real name of this is passed in by the build system. This way it can be a unique
  491  *       variable for each component.
  492  */
  493 //--------------------------------------------------------------------------------------------------
  494 extern LE_SHARED le_log_SessionRef_t LE_LOG_SESSION;
  495 
  496 //--------------------------------------------------------------------------------------------------
  497 /**
  498  * Filtering level for the current source file.
  499  *
  500  * @note The real name of this is passed in by the build system. This way it can be a unique
  501  *       variable for each component.
  502  */
  503 //--------------------------------------------------------------------------------------------------
  504 extern LE_SHARED le_log_Level_t* LE_LOG_LEVEL_FILTER_PTR;
  505 
  506 //--------------------------------------------------------------------------------------------------
  507 /**
  508  * Internal macro to set whether the function name is displayed with log messages.
  509  */
  510 //--------------------------------------------------------------------------------------------------
  511 #if LE_CONFIG_LOG_FUNCTION_NAMES
  512 #   define _LE_LOG_FUNCTION_NAME __func__
  513 #else
  514 #   define _LE_LOG_FUNCTION_NAME NULL
  515 #endif
  516 
  517 /// @endcond
  518 //--------------------------------------------------------------------------------------------------
  519 
  520 //--------------------------------------------------------------------------------------------------
  521 /**
  522  * Internal macro to filter out messages that do not meet the current filtering level.
  523  */
  524 //--------------------------------------------------------------------------------------------------
  525 #define _LE_LOG_MSG(level, formatString, ...) \
  526     do { \
  527         if ((level >= LE_LOG_LEVEL_STATIC_FILTER) &&                        \
  528             ((LE_LOG_LEVEL_FILTER_PTR == NULL) || (level >= *LE_LOG_LEVEL_FILTER_PTR))) \
  529             _le_log_Send(level, NULL, LE_LOG_SESSION, __FILE__, _LE_LOG_FUNCTION_NAME, __LINE__, \
  530                     formatString, ##__VA_ARGS__); \
  531     } while(0)
  532 
  533 
  534 //--------------------------------------------------------------------------------------------------
  535 /** @internal
  536  * The following macros are used to send log messages at different severity levels:
  537  *
  538  * Accepts printf-style arguments, consisting of a format string followed by zero or more parameters
  539  * to be printed (depending on the contents of the format string).
  540  */
  541 //--------------------------------------------------------------------------------------------------
  542 
  543 /** @copydoc LE_LOG_DEBUG */
  544 #define LE_DEBUG(formatString, ...)     _LE_LOG_MSG(LE_LOG_DEBUG, formatString, ##__VA_ARGS__)
  545 
  546 //--------------------------------------------------------------------------------------------------
  547 /**
  548  * Dump a buffer of data as hexadecimal to the log at debug level.
  549  *
  550  *  @param  dataPtr     Binary data to dump.
  551  *  @param  dataLength  Length og the buffer.
  552  */
  553 //--------------------------------------------------------------------------------------------------
  554 #define LE_DUMP(dataPtr, dataLength)                                                              \
  555     _le_LogData(LE_LOG_DEBUG, dataPtr, dataLength, STRINGIZE(LE_FILENAME), _LE_LOG_FUNCTION_NAME, \
  556         __LINE__)
  557 
  558 //--------------------------------------------------------------------------------------------------
  559 /**
  560  * Dump a buffer of data as hexadecimal to the log at the specified level.
  561  *
  562  *  @param  level       Log level.
  563  *  @param  dataPtr     Binary data to dump.
  564  *  @param  dataLength  Length of the buffer.
  565  */
  566 //--------------------------------------------------------------------------------------------------
  567 #define LE_LOG_DUMP(level, dataPtr, dataLength) \
  568     _le_LogData(level, dataPtr, dataLength, STRINGIZE(LE_FILENAME), _LE_LOG_FUNCTION_NAME, __LINE__)
  569 /** @copydoc LE_LOG_INFO */
  570 #define LE_INFO(formatString, ...)      _LE_LOG_MSG(LE_LOG_INFO, formatString, ##__VA_ARGS__)
  571 /** @copydoc LE_LOG_WARN */
  572 #define LE_WARN(formatString, ...)      _LE_LOG_MSG(LE_LOG_WARN, formatString, ##__VA_ARGS__)
  573 /** @copydoc LE_LOG_ERR */
  574 #define LE_ERROR(formatString, ...)     _LE_LOG_MSG(LE_LOG_ERR, formatString, ##__VA_ARGS__)
  575 /** @copydoc LE_LOG_CRIT */
  576 #define LE_CRIT(formatString, ...)      _LE_LOG_MSG(LE_LOG_CRIT, formatString, ##__VA_ARGS__)
  577 /** @copydoc LE_LOG_EMERG */
  578 #define LE_EMERG(formatString, ...)     _LE_LOG_MSG(LE_LOG_EMERG, formatString, ##__VA_ARGS__)
  579 
  580 
  581 //--------------------------------------------------------------------------------------------------
  582 /**
  583  * Mark tracing as used, so trace-related code can be compiled in.
  584  */
  585 //--------------------------------------------------------------------------------------------------
  586 #define LE_LOG_CAN_TRACE        1
  587 
  588 
  589 //--------------------------------------------------------------------------------------------------
  590 /**
  591  * Queries whether or not a trace keyword is enabled.
  592  *
  593  * @return
  594  *      true if the keyword is enabled.
  595  *      false otherwise.
  596  */
  597 //--------------------------------------------------------------------------------------------------
  598 #define LE_IS_TRACE_ENABLED(traceRef)  (le_log_IsTraceEnabled(traceRef))
  599 
  600 
  601 //--------------------------------------------------------------------------------------------------
  602 /**
  603  * Logs the string if the keyword has been enabled by a runtime tool or configuration setting.
  604  */
  605 //--------------------------------------------------------------------------------------------------
  606 #define LE_TRACE(traceRef, string, ...)         \
  607         if (le_log_IsTraceEnabled(traceRef))    \
  608         {                                       \
  609             _le_log_Send((le_log_Level_t)-1,    \
  610                     traceRef,                   \
  611                     LE_LOG_SESSION,             \
  612                     STRINGIZE(LE_FILENAME),     \
  613                     _LE_LOG_FUNCTION_NAME,      \
  614                     __LINE__,                   \
  615                     string,                     \
  616                     ##__VA_ARGS__);             \
  617         }
  618 
  619 
  620 //--------------------------------------------------------------------------------------------------
  621 /**
  622  * Gets a reference to a trace keyword's settings.
  623  *
  624  * @param keywordPtr   [IN] Pointer to the keyword string.
  625  *
  626  * @return  Trace reference.
  627  **/
  628 //--------------------------------------------------------------------------------------------------
  629 #define le_log_GetTraceRef(keywordPtr)                  \
  630     _le_log_GetTraceRef(LE_LOG_SESSION, (keywordPtr))
  631 
  632 
  633 //--------------------------------------------------------------------------------------------------
  634 /**
  635  * Determines if a trace is currently enabled.
  636  *
  637  * @param traceRef    [IN] Trace reference obtained from le_log_GetTraceRef()
  638  *
  639  * @return  true if enabled, false if not.
  640  **/
  641 //--------------------------------------------------------------------------------------------------
  642 #define le_log_IsTraceEnabled(traceRef) ((traceRef) == NULL ? false : *((bool *) (traceRef)))
  643 
  644 
  645 //--------------------------------------------------------------------------------------------------
  646 /**
  647  * Sets the log filter level for the calling component.
  648  *
  649  * @note    Normally not necessary as the log filter level can be controlled at
  650  *          runtime using the log control tool, and can be persistently configured.
  651  *          See @ref c_log_controlling.
  652  *
  653  * @param level   [IN] Log filter level to apply to the current log session.
  654  **/
  655 //--------------------------------------------------------------------------------------------------
  656 #define le_log_SetFilterLevel(level)                    \
  657     _le_log_SetFilterLevel(LE_LOG_SESSION, (level))
  658 
  659 
  660 //--------------------------------------------------------------------------------------------------
  661 /**
  662  * Gets the log filter level for the calling component.
  663  **/
  664 //--------------------------------------------------------------------------------------------------
  665 #define le_log_GetFilterLevel()                 \
  666     ((LE_LOG_LEVEL_FILTER_PTR != NULL)?(*LE_LOG_LEVEL_FILTER_PTR):(LE_LOG_INFO))
  667 
  668 
  669 //--------------------------------------------------------------------------------------------------
  670 /**
  671  * Enables a trace.
  672  *
  673  * @note    Normally, this is not necessary, since traces can be enabled at runtime using the
  674  *          log control tool and can be persistently configured.  See @ref c_log_controlling.
  675  *
  676  * @param traceRef    [IN] Trace reference obtained from le_log_GetTraceRef()
  677  *
  678  **/
  679 //--------------------------------------------------------------------------------------------------
  680 #define le_log_EnableTrace(traceRef)            \
  681     ((void)(*((bool*)(traceRef)) = true))
  682 
  683 
  684 //--------------------------------------------------------------------------------------------------
  685 /**
  686  * Disables a trace.
  687  *
  688  * @note    Normally, this is not necessary, since traces can be enabled at runtime using the
  689  *          log control tool and can be persistently configured.  See @ref c_log_controlling.
  690  *
  691  * @param traceRef    [IN] Trace reference obtained from le_log_GetTraceRef()
  692  *
  693  **/
  694 //--------------------------------------------------------------------------------------------------
  695 #define le_log_DisableTrace(traceRef)           \
  696     ((void)(*((bool*)(traceRef)) = false))
  697 
  698 #else
  699 
  700 // If any logging macro is overridden, all logging macros must be overridden.
  701 #if !defined(LE_DEBUG)
  702 #  error "Logging are overridden, but LE_DEBUG not defined.  Define LE_DEBUG."
  703 #endif
  704 
  705 #if !defined(LE_DUMP)
  706 #  error "Logging are overridden, but LE_DUMP not defined.  Define LE_DUMP."
  707 #endif
  708 
  709 #if !defined(LE_LOG_DUMP)
  710 #  error "Logging are overridden, but LE_LOG_DUMP not defined.  Define LE_LOG_DUMP."
  711 #endif
  712 
  713 #if !defined(LE_INFO)
  714 #  error "Logging are overridden, but LE_INFO not defined.  Define LE_INFO."
  715 #endif
  716 
  717 #if !defined(LE_WARN)
  718 #  error "Logging are overridden, but LE_WARN not defined.  Define LE_WARN."
  719 #endif
  720 
  721 #if !defined(LE_ERROR)
  722 #  error "Logging are overridden, but LE_ERROR not defined.  Define LE_ERROR."
  723 #endif
  724 
  725 #if !defined(LE_CRIT)
  726 #  error "Logging are overridden, but LE_CRIT not defined.  Define LE_CRIT."
  727 #endif
  728 
  729 #if !defined(LE_EMERG)
  730 #  error "Logging are overridden, but LE_EMERG not defined.  Define LE_EMERG."
  731 #endif
  732 
  733 // If SetFilterLevel is not defined when logging is overridden,
  734 // assume it cannot be set programatically
  735 #ifndef le_log_SetFilterLevel
  736 //--------------------------------------------------------------------------------------------------
  737 /**
  738  * Sets the log filter level for the calling component.
  739  *
  740  * @note    Normally not necessary as the log filter level can be controlled at
  741  *          runtime using the log control tool, and can be persistently configured.
  742  *          See @ref c_log_controlling.
  743  *
  744  * @param level   [IN] Log filter level to apply to the current log session.
  745  **/
  746 //--------------------------------------------------------------------------------------------------
  747 #define le_log_SetFilterLevel(level) ((void)(level))
  748 #endif
  749 
  750 
  751 // If le_log_GetFilterLevel is not defined when logging is overridden, assume it
  752 // cannot be obtained programatically.  In this case code should assume filter level
  753 // is equal to static filter level
  754 #ifndef le_log_GetFilterLevel
  755 //--------------------------------------------------------------------------------------------------
  756 /**
  757  * Gets the log filter level for the calling component.
  758  **/
  759 //--------------------------------------------------------------------------------------------------
  760 #define le_log_GetFilterLevel()  (LE_LOG_LEVEL_STATIC_FILTER)
  761 #endif
  762 
  763 //--------------------------------------------------------------------------------------------------
  764 /*
  765  * If logging is overridden, disable Legato tracing mechanism.  Tracing is noisy and should
  766  * not be put into general logs.
  767  */
  768 //--------------------------------------------------------------------------------------------------
  769 
  770 //--------------------------------------------------------------------------------------------------
  771 /**
  772  * Queries whether or not a trace keyword is enabled.
  773  *
  774  * @return
  775  *      true if the keyword is enabled.
  776  *      false otherwise.
  777  */
  778 //--------------------------------------------------------------------------------------------------
  779 #define LE_IS_TRACE_ENABLED(traceRef)  (false)
  780 
  781 
  782 //--------------------------------------------------------------------------------------------------
  783 /**
  784  * Logs the string if the keyword has been enabled by a runtime tool or configuration setting.
  785  */
  786 //--------------------------------------------------------------------------------------------------
  787 #define LE_TRACE(traceRef, string, ...) ((void)(traceRef))
  788 
  789 
  790 //--------------------------------------------------------------------------------------------------
  791 /**
  792  * Gets a reference to a trace keyword's settings.
  793  *
  794  * @param keywordPtr   [IN] Pointer to the keyword string.
  795  *
  796  * @return  Trace reference.
  797  **/
  798 //--------------------------------------------------------------------------------------------------
  799 #define le_log_GetTraceRef(keywordPtr) ((le_log_TraceRef_t)NULL)
  800 
  801 
  802 //--------------------------------------------------------------------------------------------------
  803 /**
  804  * Determines if a trace is currently enabled.
  805  *
  806  * @param traceRef    [IN] Trace reference obtained from le_log_GetTraceRef()
  807  *
  808  * @return  true if enabled, false if not.
  809  **/
  810 //--------------------------------------------------------------------------------------------------
  811 #define le_log_IsTraceEnabled(traceRef) (false)
  812 
  813 
  814 //--------------------------------------------------------------------------------------------------
  815 /**
  816  * Enables a trace.
  817  *
  818  * @note    Normally, this is not necessary, since traces can be enabled at runtime using the
  819  *          log control tool and can be persistently configured.  See @ref c_log_controlling.
  820  *
  821  * @param traceRef    [IN] Trace reference obtained from le_log_GetTraceRef()
  822  *
  823  **/
  824 //--------------------------------------------------------------------------------------------------
  825 #define le_log_EnableTrace(traceRef) ((void)(0))
  826 
  827 
  828 //--------------------------------------------------------------------------------------------------
  829 /**
  830  * Disables a trace.
  831  *
  832  * @note    Normally, this is not necessary, since traces can be enabled at runtime using the
  833  *          log control tool and can be persistently configured.  See @ref c_log_controlling.
  834  *
  835  * @param traceRef    [IN] Trace reference obtained from le_log_GetTraceRef()
  836  *
  837  **/
  838 //--------------------------------------------------------------------------------------------------
  839 #define le_log_DisableTrace(traceRef) ((void)(0))
  840 
  841 #endif /* Logging macro override */
  842 
  843 /// Function that does the real work of translating result codes.  See @ref LE_RESULT_TXT.
  844 const char* _le_log_GetResultCodeString
  845 (
  846     le_result_t resultCode  ///< [in] Result code value to be translated.
  847 );
  848 
  849 /// Function that exits in a race-free manner -- work around glibc BZ#14333
  850 __attribute__((noreturn))
  851 void _le_log_ExitFatal
  852 (
  853     void
  854 );
  855 
  856 //--------------------------------------------------------------------------------------------------
  857 /** @internal
  858  * The following macros are used to send log messages at different severity levels conditionally.
  859  * If the condition is true the message is logged.  If the condition is false the message is not
  860  * logged.
  861  *
  862  * Accepts printf-style arguments, consisting of a format string followed by zero or more parameters
  863  * to be printed (depending on the contents of the format string).
  864  */
  865 //--------------------------------------------------------------------------------------------------
  866 
  867 /** @ref LE_DEBUG if condition is met. */
  868 #define LE_DEBUG_IF(condition, formatString, ...) \
  869         if (condition) { LE_DEBUG(formatString, ##__VA_ARGS__); }
  870 /** @ref LE_INFO if condition is met. */
  871 #define LE_INFO_IF(condition, formatString, ...) \
  872         if (condition) { LE_INFO(formatString, ##__VA_ARGS__); }
  873 /** @ref LE_WARN if condition is met. */
  874 #define LE_WARN_IF(condition, formatString, ...) \
  875         if (condition) { LE_WARN(formatString, ##__VA_ARGS__); }
  876 /** @ref LE_ERROR if condition is met. */
  877 #define LE_ERROR_IF(condition, formatString, ...) \
  878         if (condition) { LE_ERROR(formatString, ##__VA_ARGS__); }
  879 /** @ref LE_CRIT if condition is met. */
  880 #define LE_CRIT_IF(condition, formatString, ...) \
  881         if (condition) { LE_CRIT(formatString, ##__VA_ARGS__); }
  882 /** @ref LE_EMERG if condition is met. */
  883 #define LE_EMERG_IF(condition, formatString, ...) \
  884         if (condition) { LE_EMERG(formatString, ##__VA_ARGS__); }
  885 
  886 
  887 //--------------------------------------------------------------------------------------------------
  888 /**
  889  * Log fatal errors by killing the calling process after logging the message at EMERGENCY
  890  * level.  This macro never returns.
  891  *
  892  * Accepts printf-style arguments, consisting of a format string followed by zero or more parameters
  893  * to be printed (depending on the contents of the format string).
  894  */
  895 //--------------------------------------------------------------------------------------------------
  896 #if !LE_CONFIG_DEBUG
  897 #define LE_FATAL(formatString, ...) \
  898         { LE_EMERG(formatString, ##__VA_ARGS__); _le_log_ExitFatal(); }
  899 #else
  900 #define LE_FATAL(formatString, ...) \
  901         { LE_EMERG(formatString, ##__VA_ARGS__); abort(); }
  902 #endif
  903 
  904 
  905 //--------------------------------------------------------------------------------------------------
  906 /**
  907  * This macro does nothing if the condition is false, otherwise it logs the message at EMERGENCY
  908  * level and then kills the calling process.
  909  *
  910  * Accepts printf-style arguments, consisting of a format string followed by zero or more parameters
  911  * to be printed (depending on the contents of the format string).
  912  */
  913 //--------------------------------------------------------------------------------------------------
  914 #define LE_FATAL_IF(condition, formatString, ...) \
  915         if (condition) { LE_FATAL(formatString, ##__VA_ARGS__) }
  916 
  917 
  918 //--------------------------------------------------------------------------------------------------
  919 /**
  920  * This macro does nothing if the condition is true, otherwise it logs the condition expression as
  921  * a message at EMERGENCY level and then kills the calling process.
  922  */
  923 //--------------------------------------------------------------------------------------------------
  924 #define LE_ASSERT(condition)                            \
  925     LE_FATAL_IF(!(condition), "Assert Failed: '%s'", #condition)
  926 
  927 
  928 //--------------------------------------------------------------------------------------------------
  929 /**
  930  * This macro does nothing if the condition is LE_OK (0), otherwise it logs that the expression did
  931  * not evaluate to LE_OK (0) in a message at EMERGENCY level and then kills the calling process.
  932  */
  933 //--------------------------------------------------------------------------------------------------
  934 #define LE_ASSERT_OK(condition)                                         \
  935     LE_FATAL_IF((condition) != LE_OK, "Assert Failed: '%s' is not LE_OK (0)", #condition)
  936 
  937 
  938 //--------------------------------------------------------------------------------------------------
  939 /**
  940  * Get a null-terminated, printable string representing an le_result_t value.
  941  *
  942  * For example, LE_RESULT_TXT(LE_NOT_PERMITTED) would return a pointer to a string containing
  943  * "LE_NOT_PERMITTED".
  944  *
  945  * "(unknown)" will be returned if the value given is out of range.
  946  *
  947  * @return Pointer to a string constant.
  948  */
  949 //--------------------------------------------------------------------------------------------------
  950 #define LE_RESULT_TXT(v) _le_log_GetResultCodeString(v)
  951 
  952 //--------------------------------------------------------------------------------------------------
  953 /**
  954  * Connects to the Log Control Daemon.  This must not be done until after the Messaging system
  955  * is initialized, but must be done before the main thread's Event Loop starts to ensure that
  956  * all log settings are received from the Log Control Daemon and applied to sessions in the local
  957  * process before any component initialization functions are run.
  958  */
  959 //--------------------------------------------------------------------------------------------------
  960 LE_FULL_API void le_log_ConnectToControlDaemon
  961 (
  962     void
  963 );
  964 
  965 //--------------------------------------------------------------------------------------------------
  966 /**
  967  * Registers a named component with the logging system.
  968  *
  969  * @return
  970  *      A log session reference.  This reference must be kept by the component and accessible
  971  *      through a local macro with the name LE_LOG_SESSION.
  972  */
  973 //--------------------------------------------------------------------------------------------------
  974 LE_FULL_API le_log_SessionRef_t le_log_RegComponent
  975 (
  976     const char       *componentNamePtr, ///< [IN] A pointer to the component's name.
  977     le_log_Level_t  **levelFilterPtrPtr ///< [OUT] Set to point to the component's level filter.
  978 );
  979 
  980 #endif // LEGATO_LOG_INCLUDE_GUARD
le_log_RegComponent
LE_FULL_API le_log_SessionRef_t le_log_RegComponent(const char *componentNamePtr, le_log_Level_t **levelFilterPtrPtr)
LE_SHARED
#define LE_SHARED
Definition: le_basics.h:284
le_result_t
le_result_t
Definition: le_basics.h:45
LE_LOG_WARN
Warning. Possibly indicates a problem. Should be addressed. 
Definition: le_log.h:378
le_log_Level_t
le_log_Level_t
Definition: le_log.h:374
LE_LOG_DEBUG
Debug message. 
Definition: le_log.h:376
LE_LOG_ERR
Definition: le_log.h:379
_le_log_GetResultCodeString
const char * _le_log_GetResultCodeString(le_result_t resultCode)
Function that does the real work of translating result codes. See LE_RESULT_TXT. 
le_log_ConnectToControlDaemon
LE_FULL_API void le_log_ConnectToControlDaemon(void)
LE_LOG_CRIT
Definition: le_log.h:381
LE_FULL_API
#define LE_FULL_API
Definition: le_apiFeatures.h:40
LE_LOG_INFO
Informational message. Normally expected. 
Definition: le_log.h:377
LE_LOG_EMERG
Emergency. A fatal error has occurred. A process is being terminated. 
Definition: le_log.h:383
_le_log_ExitFatal
void _le_log_ExitFatal(void)
Function that exits in a race-free manner -- work around glibc BZ#14333.