NAME

       Logging - MongoDB C driver Logging Abstraction

SYNOPSIS

       typedef enum
       {
          MONGOC_LOG_LEVEL_ERROR,
          MONGOC_LOG_LEVEL_CRITICAL,
          MONGOC_LOG_LEVEL_WARNING,
          MONGOC_LOG_LEVEL_MESSAGE,
          MONGOC_LOG_LEVEL_INFO,
          MONGOC_LOG_LEVEL_DEBUG,
          MONGOC_LOG_LEVEL_TRACE,
       } mongoc_log_level_t;

       #define MONGOC_ERROR(...)
       #define MONGOC_CRITICAL(...)
       #define MONGOC_WARNING(...)
       #define MONGOC_MESSAGE(...)
       #define MONGOC_INFO(...)
       #define MONGOC_DEBUG(...)

       typedef void (*mongoc_log_func_t) (mongoc_log_level_t  log_level,
                                          const char         *log_domain,
                                          const char         *message,
                                          void               *user_data);

       void        mongoc_log_set_handler     (mongoc_log_func_t   log_func,
                                               void               *user_data);
       void        mongoc_log                 (mongoc_log_level_t  log_level,
                                               const char         *log_domain,
                                               const char         *format,
                                               ...) BSON_GNUC_PRINTF(3, 4);
       const char *mongoc_log_level_str       (mongoc_log_level_t log_level);
       void        mongoc_log_default_handler (mongoc_log_level_t  log_level,
                                               const char         *log_domain,
                                               const char         *message,
                                               void               *user_data);

       The  MongoDB  C  driver  comes  with  an  abstraction for logging that you can use in your
       application, or integrate with an existing logging system.

MACROS

       To make logging a little less  painful,  various  helper  macros  are  provided.  See  the
       following example.

       #undef MONGOC_LOG_DOMAIN
       #define MONGOC_LOG_DOMAIN "my‐custom‐domain"

       MONGOC_WARNING ("An error occurred: %s", strerror (errno));

TRACING

       If  compiling  your  own copy of the MongoDB C driver, consider configuring with ‐‐enable‐
       tracing to enable function tracing and hex dumps of network packets to STDERR  and  STDOUT
       during development and debugging.

       This is especially useful when debugging what may be going on internally in the driver.

       Trace  messages  can  be  enabled  and  disabled by calling mongoc_log_trace_enable(3) and
       mongoc_log_trace_disable(3)

       NOTE
              Compiling the driver with ‐‐enable‐tracing will affect its  performance.  Disabling
              tracing  with  mongoc_log_trace_disable(3)  significantly reduces the overhead, but
              cannot remove it completely.

CUSTOM LOG HANDLERS

       The default log handler prints a timestamp and the log message to stdout ,  or  to  stderr
       for warnings, critical messages, and errors.
           You can override the handler with mongoc_log_set_handler(3) \&.
           Your handler function is called in a mutex for thread safety.

       To restore the default handler:

       mongoc_log_set_handler (mongoc_log_default_handler, NULL);

DISABLE LOGGING

       To  disable  all  logging,  including  warnings, critical messages and errors, you need to
       provide an empty log handler

       mongoc_log_set_handler (NULL, NULL);

COLOPHON

       This   page   is   part   of   MongoDB   C   Driver.    Please   report   any   bugs    at
       https://jira.mongodb.org/browse/CDRIVER.