support read

weed/mount/page_writer.go

@@ -0,0 +1,95 @@
+package mount
+
+import (
+	"github.com/chrislusf/seaweedfs/weed/filesys/page_writer"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+)
+
+type PageWriter struct {
+	fh          *FileHandle
+	collection  string
+	replication string
+	chunkSize   int64
+
+	randomWriter page_writer.DirtyPages
+}
+
+var (
+	_ = page_writer.DirtyPages(&PageWriter{})
+)
+
+func newPageWriter(fh *FileHandle, chunkSize int64) *PageWriter {
+	pw := &PageWriter{
+		fh:           fh,
+		chunkSize:    chunkSize,
+		randomWriter: newMemoryChunkPages(fh, chunkSize),
+		// randomWriter: newTempFileDirtyPages(fh.f, chunkSize),
+	}
+	return pw
+}
+
+func (pw *PageWriter) AddPage(offset int64, data []byte) {
+
+	glog.V(4).Infof("%v AddPage [%d, %d)", pw.fh, offset, offset+int64(len(data)))
+
+	chunkIndex := offset / pw.chunkSize
+	for i := chunkIndex; len(data) > 0; i++ {
+		writeSize := min(int64(len(data)), (i+1)*pw.chunkSize-offset)
+		pw.addToOneChunk(i, offset, data[:writeSize])
+		offset += writeSize
+		data = data[writeSize:]
+	}
+}
+
+func (pw *PageWriter) addToOneChunk(chunkIndex, offset int64, data []byte) {
+	pw.randomWriter.AddPage(offset, data)
+}
+
+func (pw *PageWriter) FlushData() error {
+	return pw.randomWriter.FlushData()
+}
+
+func (pw *PageWriter) ReadDirtyDataAt(data []byte, offset int64) (maxStop int64) {
+	glog.V(4).Infof("ReadDirtyDataAt %v [%d, %d)", pw.fh, offset, offset+int64(len(data)))
+
+	chunkIndex := offset / pw.chunkSize
+	for i := chunkIndex; len(data) > 0; i++ {
+		readSize := min(int64(len(data)), (i+1)*pw.chunkSize-offset)
+
+		maxStop = pw.randomWriter.ReadDirtyDataAt(data[:readSize], offset)
+
+		offset += readSize
+		data = data[readSize:]
+	}
+
+	return
+}
+
+func (pw *PageWriter) GetStorageOptions() (collection, replication string) {
+	return pw.randomWriter.GetStorageOptions()
+}
+
+func (pw *PageWriter) LockForRead(startOffset, stopOffset int64) {
+	pw.randomWriter.LockForRead(startOffset, stopOffset)
+}
+
+func (pw *PageWriter) UnlockForRead(startOffset, stopOffset int64) {
+	pw.randomWriter.UnlockForRead(startOffset, stopOffset)
+}
+
+func (pw *PageWriter) Destroy() {
+	pw.randomWriter.Destroy()
+}
+
+func max(x, y int64) int64 {
+	if x > y {
+		return x
+	}
+	return y
+}
+func min(x, y int64) int64 {
+	if x < y {
+		return x
+	}
+	return y
+}