[logging] add CONFIG_LOG_PREPEND_UPTIME to prepend uptime to the log (#6968)

This commit adds `OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME` config to
prepend the current uptime (as "[x days] hh::mm::ss.mmmm") to the
OpenThread log messages.

src/core/common/logging.cpp

@@ -43,7 +43,15 @@
  * It is reasonable to only enable the debug uart and not enable logs to the DEBUG uart.
  */
 #if (OPENTHREAD_CONFIG_LOG_OUTPUT == OPENTHREAD_CONFIG_LOG_OUTPUT_DEBUG_UART) && (!OPENTHREAD_CONFIG_ENABLE_DEBUG_UART)
-#error OPENTHREAD_CONFIG_ENABLE_DEBUG_UART_LOG requires OPENTHREAD_CONFIG_ENABLE_DEBUG_UART
+#error "OPENTHREAD_CONFIG_ENABLE_DEBUG_UART_LOG requires OPENTHREAD_CONFIG_ENABLE_DEBUG_UART"
+#endif
+
+#if OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME && !OPENTHREAD_CONFIG_UPTIME_ENABLE
+#error "OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME requires OPENTHREAD_CONFIG_UPTIME_ENABLE"
+#endif
+
+#if OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME && OPENTHREAD_CONFIG_MULTIPLE_INSTANCE_ENABLE
+#error "OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME is not supported under OPENTHREAD_CONFIG_MULTIPLE_INSTANCE_ENABLE"
 #endif
 
 #ifdef __cplusplus
@@ -56,6 +64,11 @@ static void Log(otLogLevel aLogLevel, otLogRegion aLogRegion, const char *aForma
 {
     ot::String<OPENTHREAD_CONFIG_LOG_MAX_SIZE> logString;
 
+#if OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME
+    ot::Uptime::UptimeToString(ot::Instance::Get().Get<ot::Uptime>().GetUptime(), logString);
+    logString.Append(" ");
+#endif
+
 #if OPENTHREAD_CONFIG_LOG_LEVEL_DYNAMIC_ENABLE
     VerifyOrExit(otLoggingGetLevel() >= aLogLevel);
 #endif

src/core/config/logging.h

@@ -339,6 +339,16 @@
 #define OPENTHREAD_CONFIG_LOG_DNS 1
 #endif
 
+/**
+ * @def OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME
+ *
+ * Define as 1 to prepend the current uptime to all log messages.
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME
+#define OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME 0
+#endif
+
 /**
  * @def OPENTHREAD_CONFIG_LOG_PREPEND_LEVEL
  *

tests/toranj/openthread-core-toranj-config.h

@@ -288,13 +288,21 @@
  */
 #define OPENTHREAD_CONFIG_LOG_LEVEL_DYNAMIC_ENABLE 1
 
+/**
+ * @def OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME
+ *
+ * Define as 1 to prepend the current uptime to all log messages.
+ *
+ */
+#define OPENTHREAD_CONFIG_LOG_PREPEND_UPTIME 1
+
 /**
  * @def OPENTHREAD_CONFIG_LOG_PREPEND_LEVEL
  *
  * Define to prepend the log level to all log messages
  *
  */
-#define OPENTHREAD_CONFIG_LOG_PREPEND_LEVEL 0
+#define OPENTHREAD_CONFIG_LOG_PREPEND_LEVEL 1
 
 /**
  * @def OPENTHREAD_CONFIG_LOG_PREPEND_REGION
@@ -302,7 +310,7 @@
  * Define to prepend the log region to all log messages
  *
  */
-#define OPENTHREAD_CONFIG_LOG_PREPEND_REGION 0
+#define OPENTHREAD_CONFIG_LOG_PREPEND_REGION 1
 
 /**
  * @def OPENTHREAD_CONFIG_LOG_SUFFIX