Main: Update documentation

[libucw.git] / ucw / log.h

diff --git a/ucw/log.h b/ucw/log.h
index 3c7264a6deaa1880faf053d5bc0f4a30bb9cfa9f..f2d99a0729d19e5ff79fdd06a26946743654d8d8 100644 (file)
--- a/ucw/log.h
+++ b/ucw/log.h
@@ -22,6 +22,7 @@ struct log_msg {
   char *m;                             // The formatted message itself, ending with \n\0
   int m_len;                           // Length without the \0
   struct tm *tm;                       // Current time
+  struct timeval *tv;
   uns flags;                           // Category and other flags as passed to msg()
   char *raw_msg;                       // Unformatted parts
   char *stime;
@@ -35,6 +36,7 @@ struct log_stream {
   char *name;                          // Optional name, allocated by the user (or constructor)
   int regnum;                          // Stream number, already encoded by LS_SET_STRNUM(); -1 if closed
   uns levels;                          // Bitmask of accepted severity levels (default: all)
+  uns types;                           // Bitmask of accepted message types (default: all)
   uns msgfmt;                          // Formatting flags (LSFMT_xxx)
   uns use_count;                       // Number of references to the stream
   uns stream_flags;                    // Various other flags (LSFLAG_xxx)
@@ -42,6 +44,7 @@ struct log_stream {
   clist substreams;                    // Pass the message to these streams (simple_list of pointers)
   int (*handler)(struct log_stream *ls, struct log_msg *m);    // Called to commit the message, return 0 for success, errno on error
   void (*close)(struct log_stream* ls);        // Called upon log_close_stream()
+  void *user_data;                     // Not used by the logging system
   // Private data of the handler follow
 };
 
@@ -55,6 +58,7 @@ enum ls_fmt {
   LSFMT_TITLE =                8,              // program title (log_title) */
   LSFMT_PID =          16,             // program PID (log_pid) */
   LSFMT_LOGNAME =      32,             // name of the log_stream */
+  LSFMT_TYPE =         64,             // message type
 };
 
 #define LSFMT_DEFAULT (LSFMT_LEVEL | LSFMT_TIME | LSFMT_TITLE | LSFMT_PID)     /** Default format **/
@@ -71,7 +75,7 @@ enum ls_flag {
  * === Message flags
  *
  * The @flags parameter of msg() is divided to several groups of bits (from the LSB):
- * message severity level (`L_xxx`), destination stream, message type [currently unused]
+ * message severity level (`L_xxx`), destination stream, message type
  * and control bits (e.g., `L_SIGHANDLER`).
  ***/
 
@@ -108,6 +112,17 @@ enum ls_flagmasks {                        // Bit masks of groups
 #define LS_SET_TYPE(type)      ((type) << LS_TYPE_POS)                         /** Convert message type to flags **/
 #define LS_SET_CTRL(ctrl)      ((ctrl) << LS_CTRL_POS)                         /** Convert control bits to flags **/
 
+#define LS_NUM_TYPES (1 << LS_TYPE_BITS)
+
+/** Register a new message type and return the corresponding flag set (encoded by `LS_SET_TYPE`). **/
+int log_register_type(const char *name);
+
+/** Find a message type by name and return the corresponding flag set. Returns -1 if no such type found. **/
+int log_find_type(const char *name);
+
+/** Given a flag set, extract the message type ID and return its name. **/
+char *log_type_name(uns flags);
+
 /*** === Operations on streams ***/
 
 /**
@@ -177,8 +192,14 @@ void log_close_all(void);
  * even in multi-threaded programs.
  ***/
 
-struct log_stream *log_new_file(const char *path);             /** Create a stream bound to a log file. **/
-struct log_stream *log_new_fd(int fd);                         /** Create a stream bound to a file descriptor. **/
+struct log_stream *log_new_file(const char *path, uns flags);  /** Create a stream bound to a log file. See `FF_xxx` for @flags. **/
+struct log_stream *log_new_fd(int fd, uns flags);              /** Create a stream bound to a file descriptor. See `FF_xxx` for @flags. **/
+
+enum log_file_flag {           /** Flags used for file-based logging **/
+  FF_FORMAT_NAME = 1,          // Internal: Name contains strftime escapes
+  FF_CLOSE_FD = 2,             // Close the fd with the stream (use with log_new_fd())
+  FF_FD2_FOLLOWS = 4,          // Maintain stderr as a clone of this stream
+};
 
 /**
  * When a time-based name of the log file changes, the logger switches to a new