intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 59 insertions, 0 deletions

diff --git a/library/cpp/logger/file.cpp b/library/cpp/logger/file.cpp
new file mode 100644
index 0000000000..15a4946eda
--- /dev/null
+++ b/library/cpp/logger/file.cpp
@@ -0,0 +1,59 @@
+#include "file.h"
+#include "record.h"
+
+#include <util/system/file.h>
+#include <util/system/rwlock.h>
+#include <util/generic/string.h>
+
+/*
+ * file log
+ */
+class TFileLogBackend::TImpl {
+public:
+    inline TImpl(const TString& path)
+        : File_(OpenFile(path))
+    {
+    }
+
+    inline void WriteData(const TLogRecord& rec) {
+        //many writes are thread-safe
+        TReadGuard guard(Lock_);
+
+        File_.Write(rec.Data, rec.Len);
+    }
+
+    inline void ReopenLog() {
+        //but log rotate not thread-safe
+        TWriteGuard guard(Lock_);
+
+        File_.LinkTo(OpenFile(File_.GetName()));
+    }
+
+private:
+    static inline TFile OpenFile(const TString& path) {
+        return TFile(path, OpenAlways | WrOnly | ForAppend | Seq | NoReuse);
+    }
+
+private:
+    TRWMutex Lock_;
+    TFile File_;
+};
+
+TFileLogBackend::TFileLogBackend(const TString& path)
+    : Impl_(new TImpl(path))
+{
+}
+
+TFileLogBackend::~TFileLogBackend() {
+}
+
+void TFileLogBackend::WriteData(const TLogRecord& rec) {
+    Impl_->WriteData(rec);
+}
+
+void TFileLogBackend::ReopenLog() {
+    TAtomicSharedPtr<TImpl> copy = Impl_;
+    if (copy) {
+        copy->ReopenLog();
+    }
+}