Log new ErrorReporter and old nnapi delegate errors to logcat.

On Android stderr is not captured for applications, so developers do not see
the errors from tflite. This adds logcat output.

Output to stderr is kept, as it is convenient for unit tests run through the
shell.

PiperOrigin-RevId: 208463170

1 files changed, 13 insertions, 6 deletions

diff --git a/tensorflow/contrib/lite/nnapi_delegate.cc b/tensorflow/contrib/lite/nnapi_delegate.cc
index 13325a8c7c..3f3d3ef5d1 100644
--- a/tensorflow/contrib/lite/nnapi_delegate.cc
+++ b/tensorflow/contrib/lite/nnapi_delegate.cc
@@ -24,20 +24,27 @@ limitations under the License.
 #include "tensorflow/contrib/lite/nnapi/NeuralNetworksShim.h"
 
 #ifdef __ANDROID__
+#include <android/log.h>
 #include <sys/system_properties.h>
 #endif
 
 namespace tflite {
 
 void logError(const char* format, ...) {
-  // TODO(mikie): use android logging, stderr is not captured for Java
-  // applications
-  va_list args;
-  va_start(args, format);
-  vfprintf(stderr, format, args);
-  va_end(args);
+  // stderr is convenient for native tests, but is not captured for apps
+  va_list args_for_stderr;
+  va_start(args_for_stderr, format);
+  vfprintf(stderr, format, args_for_stderr);
+  va_end(args_for_stderr);
   fprintf(stderr, "\n");
   fflush(stderr);
+#ifdef __ANDROID__
+  // produce logcat output for general consumption
+  va_list args_for_log;
+  va_start(args_for_log, format);
+  __android_log_vprint(ANDROID_LOG_ERROR, "tflite", format, args_for_log);
+  va_end(args_for_log);
+#endif
 }
 
 #define FATAL(...)       \