implement LOG_EVENT_STRING

Implement LOG_EVENT_STRING, so that native code can create new
event log entries. This is needed to support logging SELinux denials
to the event log.

Change-Id: I6a269a832bc2f5e5da6c9dbd169ed2f901b49166
diff --git a/include/log/log.h b/include/log/log.h
index 5b76c1a..ace12d6 100644
--- a/include/log/log.h
+++ b/include/log/log.h
@@ -491,7 +491,7 @@
 #endif
 #ifndef LOG_EVENT_STRING
 #define LOG_EVENT_STRING(_tag, _value)                                      \
-    ((void) 0)  /* not implemented -- must combine len with string */
+        (void) __android_log_bswrite(_tag, _value);
 #endif
 /* TODO: something for LIST */
 
diff --git a/include/log/logd.h b/include/log/logd.h
index 379c373..2e6f220 100644
--- a/include/log/logd.h
+++ b/include/log/logd.h
@@ -41,6 +41,7 @@
 int __android_log_bwrite(int32_t tag, const void *payload, size_t len);
 int __android_log_btwrite(int32_t tag, char type, const void *payload,
     size_t len);
+int __android_log_bswrite(int32_t tag, const char *payload);
 
 #ifdef __cplusplus
 }