Initial commit

vendor/github.com/cockroachdb/pebble/vfs/logging_fs.go

@@ -0,0 +1,166 @@
+// Copyright 2021 The LevelDB-Go and Pebble Authors. All rights reserved. Use
+// of this source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package vfs
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+// WithLogging wraps an FS and logs filesystem modification operations to the
+// given logFn.
+func WithLogging(fs FS, logFn LogFn) FS {
+	return &loggingFS{
+		FS:    fs,
+		logFn: logFn,
+	}
+}
+
+// LogFn is a function that is used to capture a log when WithLogging is used.
+type LogFn func(fmt string, args ...interface{})
+
+type loggingFS struct {
+	FS
+	logFn LogFn
+}
+
+var _ FS = (*loggingFS)(nil)
+
+func (fs *loggingFS) Create(name string) (File, error) {
+	fs.logFn("create: %s", name)
+	f, err := fs.FS.Create(name)
+	if err != nil {
+		return nil, err
+	}
+	return newLoggingFile(f, name, fs.logFn), nil
+}
+
+func (fs *loggingFS) Open(name string, opts ...OpenOption) (File, error) {
+	var optsStr string
+	if len(opts) > 0 {
+		optsStr = " (options:"
+		for i := range opts {
+			optsStr += fmt.Sprintf(" %T", opts[i])
+		}
+		optsStr += ")"
+	}
+	fs.logFn("open: %s%s", name, optsStr)
+	f, err := fs.FS.Open(name, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return newLoggingFile(f, name, fs.logFn), nil
+}
+
+func (fs *loggingFS) OpenReadWrite(name string, opts ...OpenOption) (File, error) {
+	fs.logFn("open-read-write: %s", name)
+	f, err := fs.FS.OpenReadWrite(name, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return newLoggingFile(f, name, fs.logFn), nil
+}
+
+func (fs *loggingFS) Link(oldname, newname string) error {
+	fs.logFn("link: %s -> %s", oldname, newname)
+	return fs.FS.Link(oldname, newname)
+}
+
+func (fs *loggingFS) OpenDir(name string) (File, error) {
+	fs.logFn("open-dir: %s", name)
+	f, err := fs.FS.OpenDir(name)
+	if err != nil {
+		return nil, err
+	}
+	return newLoggingFile(f, name, fs.logFn), nil
+}
+
+func (fs *loggingFS) Rename(oldname, newname string) error {
+	fs.logFn("rename: %s -> %s", oldname, newname)
+	return fs.FS.Rename(oldname, newname)
+}
+
+func (fs *loggingFS) ReuseForWrite(oldname, newname string) (File, error) {
+	fs.logFn("reuseForWrite: %s -> %s", oldname, newname)
+	f, err := fs.FS.ReuseForWrite(oldname, newname)
+	if err != nil {
+		return nil, err
+	}
+	return newLoggingFile(f, newname, fs.logFn), nil
+}
+
+func (fs *loggingFS) MkdirAll(dir string, perm os.FileMode) error {
+	fs.logFn("mkdir-all: %s %#o", dir, perm)
+	return fs.FS.MkdirAll(dir, perm)
+}
+
+func (fs *loggingFS) Lock(name string) (io.Closer, error) {
+	fs.logFn("lock: %s", name)
+	return fs.FS.Lock(name)
+}
+
+func (fs loggingFS) Remove(name string) error {
+	fs.logFn("remove: %s", name)
+	err := fs.FS.Remove(name)
+	return err
+}
+
+func (fs loggingFS) RemoveAll(name string) error {
+	fs.logFn("remove-all: %s", name)
+	err := fs.FS.RemoveAll(name)
+	return err
+}
+
+type loggingFile struct {
+	File
+	name  string
+	logFn LogFn
+}
+
+var _ File = (*loggingFile)(nil)
+
+func newLoggingFile(f File, name string, logFn LogFn) *loggingFile {
+	return &loggingFile{
+		File:  f,
+		name:  name,
+		logFn: logFn,
+	}
+}
+
+func (f *loggingFile) Close() error {
+	f.logFn("close: %s", f.name)
+	return f.File.Close()
+}
+
+func (f *loggingFile) Sync() error {
+	f.logFn("sync: %s", f.name)
+	return f.File.Sync()
+}
+
+func (f *loggingFile) SyncData() error {
+	f.logFn("sync-data: %s", f.name)
+	return f.File.SyncData()
+}
+
+func (f *loggingFile) SyncTo(length int64) (fullSync bool, err error) {
+	f.logFn("sync-to(%d): %s", length, f.name)
+	return f.File.SyncTo(length)
+}
+
+func (f *loggingFile) ReadAt(p []byte, offset int64) (int, error) {
+	f.logFn("read-at(%d, %d): %s", offset, len(p), f.name)
+	return f.File.ReadAt(p, offset)
+}
+
+func (f *loggingFile) WriteAt(p []byte, offset int64) (int, error) {
+	f.logFn("write-at(%d, %d): %s", offset, len(p), f.name)
+	return f.File.WriteAt(p, offset)
+}
+
+func (f *loggingFile) Prefetch(offset int64, length int64) error {
+	f.logFn("prefetch(%d, %d): %s", offset, length, f.name)
+	return f.File.Prefetch(offset, length)
+}