mlearning/tflite-micro: add a config option to redirect micro log to syslog

mlearning/tflite-micro/CMakeLists.txt

@@ -101,6 +101,10 @@ if(CONFIG_TFLITEMICRO)
 
   # Remove test file
   list(FILTER TFLITE_MICRO_SRCS EXCLUDE REGEX ".*test.cc")
+  if(CONFIG_TFLITEMICRO_SYSLOG)
+    list(FILTER TFLITE_MICRO_SRCS EXCLUDE REGEX "micro_log.cc")
+    list(APPEND TFLITE_MICRO_SRCS ${CMAKE_CURRENT_LIST_DIR}/tflm_syslog.cc)
+  endif()
 
   if(CONFIG_MLEARNING_CMSIS_NN)
     list(APPEND COMMON_FLAGS -DCMSIS_NN)

mlearning/tflite-micro/Kconfig

@@ -32,6 +32,30 @@ config TFLITEMICRO_TOOL
 	bool "tflite-micro cmdline tool"
 	default n
 
+config TFLITEMICRO_SYSLOG
+	bool "tflite-micro syslog backend"
+	default n
+
+if TFLITEMICRO_SYSLOG
+
+config TFLITEMICRO_SYSLOG_LEVEL
+	int "tflite-micro syslog level"
+	default 6
+	---help---
+		Syslog level mapping of tflm, This log level mapping is consistent
+		with the nuttx syslog level, please refer to syslog.h:
+
+		define LOG_EMERG     0  /* System is unusable */
+		define LOG_ALERT     1  /* Action must be taken immediately */
+		define LOG_CRIT      2  /* Critical conditions */
+		define LOG_ERR       3  /* Error conditions */
+		define LOG_WARNING   4  /* Warning conditions */
+		define LOG_NOTICE    5  /* Normal, but significant, condition */
+		define LOG_INFO      6  /* Informational message */
+		define LOG_DEBUG     7  /* Debug-level message */
+
+endif # TFLITEMICRO_SYSLOG
+
 if TFLITEMICRO_TOOL
 config TFLITEMICRO_TOOL_PRIORITY
 	int "tflite-micro tool priority"

mlearning/tflite-micro/Makefile

@@ -78,6 +78,11 @@ CXXSRCS += $(wildcard $(TFLM_DIR)/tensorflow/lite/micro/tflite_bridge/*.cc)
 CXXSRCS += $(wildcard $(TFLM_DIR)/tensorflow/lite/schema/*.cc)
 CXXSRCS := $(filter-out %test.cc, $(CXXSRCS))
 
+ifneq ($(CONFIG_TFLITEMICRO_SYSLOG),)
+  CXXSRCS := $(filter-out %micro_log.cc, $(CXXSRCS))
+  CXXSRCS += $(wildcard $(CURDIR)/tflm_syslog.cc)
+endif
+
 # cmsis
 ifneq ($(CONFIG_MLEARNING_CMSIS_NN),)
 COMMON_FLAGS += -DCMSIS_NN

mlearning/tflite-micro/tflm_syslog.cc

@@ -0,0 +1,66 @@
+/****************************************************************************
+ * apps/mlearning/tflite-micro/tflm_syslog.cc
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#include "tensorflow/lite/micro/micro_log.h"
+
+#include <syslog.h>
+#include <stdio.h>
+
+#if !defined(TF_LITE_STRIP_ERROR_STRINGS)
+#include "tensorflow/lite/micro/debug_log.h"
+#endif
+
+#if !defined(TF_LITE_STRIP_ERROR_STRINGS)
+
+void VMicroPrintf(FAR const char *format, va_list ap)
+{
+  vsyslog(CONFIG_TFLITEMICRO_SYSLOG_LEVEL, format, ap);
+}
+
+void MicroPrintf(FAR const char *format, ...)
+{
+  va_list ap;
+
+  /* Let vsyslog do the work */
+
+  va_start(ap, format);
+  vsyslog(CONFIG_TFLITEMICRO_SYSLOG_LEVEL, format, ap);
+  va_end(ap);
+}
+
+int MicroSnprintf(FAR char *buffer, size_t buf_size, FAR const char *format, ...)
+{
+  va_list ap;
+  int ret;
+
+  va_start(ap, format);
+  ret = vsnprintf(buffer, buf_size, format, ap);
+  va_end(ap);
+
+  return ret;
+}
+
+int MicroVsnprintf(FAR char *buffer, size_t buf_size,
+                   FAR const char *format, va_list vlist)
+{
+  return vsnprintf(buffer, buf_size, format, vlist);
+}
+
+#endif  // !defined(TF_LITE_STRIP_ERROR_STRINGS)