Merge pull request #108 from spinetix/log-handler

Add a log handler callback.

include/coap/debug.h

@@ -41,6 +41,11 @@ coap_log_t coap_get_log_level(void);
 /** Sets the log level to the specified value. */
 void coap_set_log_level(coap_log_t level);
 
+typedef void (*coap_log_handler_t) (coap_log_t level, const char *message);
+
+/** Add a custom log callback, use NULL to reset default handler */
+void coap_set_log_handler(coap_log_handler_t handler);
+
 /** Returns a zero-terminated string with the name of this library. */
 const char *coap_package_name(void);
 

libcoap-1.sym

@@ -148,6 +148,7 @@ coap_session_set_mtu
 coap_session_str
 coap_set_app_data
 coap_set_event_handler
+coap_set_log_handler
 coap_set_log_level
 coap_show_pdu
 coap_socket_bind_udp

src/debug.c

@@ -489,30 +489,45 @@ coap_show_pdu(const coap_pdu_t *pdu) {
   fflush(COAP_DEBUG_FD);
 }
 
+static coap_log_handler_t log_handler = NULL;
+
+void coap_set_log_handler(coap_log_handler_t handler) {
+  log_handler = handler;
+}
 
 void 
 coap_log_impl(coap_log_t level, const char *format, ...) {
-  char timebuf[32];
-  coap_tick_t now;
-  va_list ap;
-  FILE *log_fd;
 
   if (maxlog < level)
     return;
+
+  if (log_handler) {
+    char message[128];
+    va_list ap;
+    va_start(ap, format);
+    vsnprintf( message, sizeof(message), format, ap);
+    va_end(ap);
+    log_handler(level, message);
+  } else {
+    char timebuf[32];
+    coap_tick_t now;
+    va_list ap;
+    FILE *log_fd;
   
-  log_fd = level <= LOG_CRIT ? COAP_ERR_FD : COAP_DEBUG_FD;
+    log_fd = level <= LOG_CRIT ? COAP_ERR_FD : COAP_DEBUG_FD;
 
-  coap_ticks(&now);
-  if (print_timestamp(timebuf,sizeof(timebuf), now))
-    fprintf(log_fd, "%s ", timebuf);
+    coap_ticks(&now);
+    if (print_timestamp(timebuf,sizeof(timebuf), now))
+      fprintf(log_fd, "%s ", timebuf);
 
-  if (level <= LOG_DEBUG)
-    fprintf(log_fd, "%s ", loglevels[level]);
+    if (level <= LOG_DEBUG)
+      fprintf(log_fd, "%s ", loglevels[level]);
 
-  va_start(ap, format);
-  vfprintf(log_fd, format, ap);
-  va_end(ap);
-  fflush(log_fd);
+    va_start(ap, format);
+    vfprintf(log_fd, format, ap);
+    va_end(ap);
+    fflush(log_fd);
+  }
 }
 
 static struct packet_num_interval {