Hide implementation details of log_time struct

In the future, the sizes of tv_sec and tv_nsec (or even the size of
log_time struct itself) can change due to the 32-bit overflow expected
to happen in the year 2138. In order to hide such implementation details
to the clients of liblog, the two macros LOG_TIME_SEC and LOG_TIME_NSEC
are introduced.

Furthermore, vendors are provided with a simplified version of log_time.h
without C++ APIs. In doing so, log_time.h no longer includes time.h.
This breaks several modules that implicitly relied on the hidden
dependency, which should be fixed.

Bug: 37629934
Test: build with BOARD_VNDK_VERSION=current
Change-Id: I01b36078c1d8f3f44824be20ae769ba1465b6feb

2 files changed, 54 insertions, 4 deletions

diff --git a/liblog/include/log/log_time.h b/liblog/include/log/log_time.h
index 3764faf75..309f5d12f 100644
--- a/liblog/include/log/log_time.h
+++ b/liblog/include/log/log_time.h
@@ -28,6 +28,10 @@
 #ifndef __struct_log_time_defined
 #define __struct_log_time_defined
 
+#define LOG_TIME_SEC(t) ((t)->tv_sec)
+/* next power of two after NS_PER_SEC */
+#define LOG_TIME_NSEC(t) ((t)->tv_nsec & (UINT32_MAX >> 2))
+
 #ifdef __cplusplus
 
 /*
@@ -167,15 +171,15 @@ struct log_time {
 #endif
 } __attribute__((__packed__));
 
-#else
+#else /* __cplusplus */
 
 typedef struct log_time {
   uint32_t tv_sec;
   uint32_t tv_nsec;
 } __attribute__((__packed__)) log_time;
 
-#endif
+#endif /* __cplusplus */
 
-#endif
+#endif /* __struct_log_time_defined */
 
 #endif /* _LIBS_LOG_LOG_TIME_H */
diff --git a/liblog/include_vndk/log/log_time.h b/liblog/include_vndk/log/log_time.h
index abfe439ae..5a09959a7 120000..100644
--- a/liblog/include_vndk/log/log_time.h
+++ b/liblog/include_vndk/log/log_time.h
@@ -1 +1,47 @@
-../../include/log/log_time.h
\ No newline at end of file
+/*
+ * Copyright (C) 2005-2017 The Android Open Source Project
+ *
+ * Licensed 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.
+ */
+
+#ifndef _LIBS_LOG_LOG_TIME_H
+#define _LIBS_LOG_LOG_TIME_H
+
+#include <stdint.h>
+
+/* struct log_time is a wire-format variant of struct timespec */
+#ifndef NS_PER_SEC
+#define NS_PER_SEC 1000000000ULL
+#endif
+#ifndef US_PER_SEC
+#define US_PER_SEC 1000000ULL
+#endif
+#ifndef MS_PER_SEC
+#define MS_PER_SEC 1000ULL
+#endif
+
+#ifndef __struct_log_time_defined
+#define __struct_log_time_defined
+
+#define LOG_TIME_SEC(t) ((t)->tv_sec)
+/* next power of two after NS_PER_SEC */
+#define LOG_TIME_NSEC(t) ((t)->tv_nsec & (UINT32_MAX >> 2))
+
+typedef struct log_time {
+  uint32_t tv_sec;
+  uint32_t tv_nsec;
+} __attribute__((__packed__)) log_time;
+
+#endif
+
+#endif /* _LIBS_LOG_LOG_TIME_H */