nearby: snapshot of cl/317978613

Signed-off-by: Alexey Polyudov <apolyudov@google.com>
Change-Id: I4bf367877a986910bb03e1c54aa972b4bcd59942

cpp/platform_v2/base/logging.h

@@ -1,6 +1,60 @@
 #ifndef PLATFORM_V2_BASE_LOGGING_H_
 #define PLATFORM_V2_BASE_LOGGING_H_
 
-#include "platform/logging.h"
+#include "platform_v2/api/log_message.h"
+#include "platform_v2/api/platform.h"
+
+namespace location {
+namespace nearby {
+
+// This class is used to explicitly ignore values in the conditional
+// logging macros.  This avoids compiler warnings like "value computed
+// is not used" and "statement has no effect".
+class LogMessageVoidify {
+ public:
+  LogMessageVoidify() = default;
+  // This has to be an operator with a precedence lower than << but
+  // higher than ?:
+  void operator&(std::ostream&) {}
+};
+
+}  // namespace nearby
+}  // namespace location
+
+// Severity enum conversion
+#define NEARBY_SEVERITY_INFO location::nearby::api::LogMessage::Severity::kInfo
+#define NEARBY_SEVERITY_WARNING \
+  location::nearby::api::LogMessage::Severity::kWarning
+#define NEARBY_SEVERITY_ERROR \
+  location::nearby::api::LogMessage::Severity::kError
+#define NEARBY_SEVERITY_FATAL \
+  location::nearby::api::LogMessage::Severity::kFatal
+
+#define NEARBY_SEVERITY(severity) NEARBY_SEVERITY_##severity
+
+// Log enabling
+#define NEARBY_LOG_IS_ON(severity)                           \
+  location::nearby::api::LogMessage::ShouldCreateLogMessage( \
+      NEARBY_SEVERITY(severity))
+
+#define NEARBY_LOG_SET_SEVERITY(severity)               \
+  location::nearby::api::LogMessage::SetMinLogSeverity( \
+      NEARBY_SEVERITY(severity))
+
+// Log message creation
+#define NEARBY_LOG_MESSAGE(severity)                               \
+  location::nearby::api::ImplementationPlatform::CreateLogMessage( \
+      __FILE__, __LINE__, NEARBY_SEVERITY(severity))
+
+// Public APIs
+// The stream statement must come last or otherwise it won't compile.
+#define NEARBY_LOGS(severity)                                             \
+  !(NEARBY_LOG_IS_ON(severity)) ? (void)0                                 \
+                                : location::nearby::LogMessageVoidify() & \
+                                      NEARBY_LOG_MESSAGE(severity)->Stream()
+
+#define NEARBY_LOG(severity, ...) \
+  NEARBY_LOG_IS_ON(severity)      \
+  ? NEARBY_LOG_MESSAGE(severity)->Print(__VA_ARGS__) : (void)0
 
 #endif  // PLATFORM_V2_BASE_LOGGING_H_