From edbd6ad58498307b028cf40f8b87a672334f8a34 Mon Sep 17 00:00:00 2001
From: Alexander Neumann <alexander@bumpern.de>
Date: Wed, 10 May 2017 19:48:22 +0200
Subject: [PATCH] Add fs.TempFile and fs.RemoveIfExists

---
 src/restic/checker/checker.go                |  4 ++--
 src/restic/fs/file.go                        |  9 +++++++++
 src/restic/fs/file_unix.go                   | 20 +++++++++++++++++++-
 src/restic/fs/file_windows.go                |  6 ++++++
 src/restic/repository/packer_manager.go      |  7 +++----
 src/restic/repository/packer_manager_test.go |  3 ++-
 src/restic/repository/repack.go              |  7 +++----
 7 files changed, 44 insertions(+), 12 deletions(-)

diff --git a/src/restic/checker/checker.go b/src/restic/checker/checker.go
index 1fd73888c..80dee3005 100644
--- a/src/restic/checker/checker.go
+++ b/src/restic/checker/checker.go
@@ -4,11 +4,11 @@ import (
 	"crypto/sha256"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"sync"
 
 	"restic/errors"
+	"restic/fs"
 	"restic/hashing"
 
 	"restic"
@@ -668,7 +668,7 @@ func checkPack(r restic.Repository, id restic.ID) error {
 		return err
 	}
 
-	packfile, err := ioutil.TempFile("", "restic-temp-check-")
+	packfile, err := fs.TempFile("", "restic-temp-check-")
 	if err != nil {
 		return errors.Wrap(err, "TempFile")
 	}
diff --git a/src/restic/fs/file.go b/src/restic/fs/file.go
index e23da2bcb..1d15a0300 100644
--- a/src/restic/fs/file.go
+++ b/src/restic/fs/file.go
@@ -116,3 +116,12 @@ func OpenFile(name string, flag int, perm os.FileMode) (*os.File, error) {
 func Walk(root string, walkFn filepath.WalkFunc) error {
 	return filepath.Walk(fixpath(root), walkFn)
 }
+
+// RemoveIfExists removes a file, returning no error if it does not exist.
+func RemoveIfExists(filename string) error {
+	err := os.Remove(filename)
+	if err != nil && os.IsNotExist(err) {
+		err = nil
+	}
+	return err
+}
diff --git a/src/restic/fs/file_unix.go b/src/restic/fs/file_unix.go
index 4c6da3964..4815fcc8b 100644
--- a/src/restic/fs/file_unix.go
+++ b/src/restic/fs/file_unix.go
@@ -2,7 +2,10 @@
 
 package fs
 
-import "os"
+import (
+	"io/ioutil"
+	"os"
+)
 
 // fixpath returns an absolute path on windows, so restic can open long file
 // names.
@@ -17,3 +20,18 @@ func fixpath(name string) string {
 func MkdirAll(path string, perm os.FileMode) error {
 	return os.MkdirAll(fixpath(path), perm)
 }
+
+// TempFile creates a temporary file which has already been deleted (on
+// supported platforms)
+func TempFile(dir, prefix string) (f *os.File, err error) {
+	f, err = ioutil.TempFile(dir, prefix)
+	if err != nil {
+		return nil, err
+	}
+
+	if err = os.Remove(f.Name()); err != nil {
+		return nil, err
+	}
+
+	return f, nil
+}
diff --git a/src/restic/fs/file_windows.go b/src/restic/fs/file_windows.go
index 8f1df7967..f8cbd1964 100644
--- a/src/restic/fs/file_windows.go
+++ b/src/restic/fs/file_windows.go
@@ -1,6 +1,7 @@
 package fs
 
 import (
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -85,3 +86,8 @@ func MkdirAll(path string, perm os.FileMode) error {
 	}
 	return nil
 }
+
+// TempFile creates a temporary file.
+func TempFile(dir, prefix string) (f *os.File, err error) {
+	return ioutil.TempFile(dir, prefix)
+}
diff --git a/src/restic/repository/packer_manager.go b/src/restic/repository/packer_manager.go
index e3f49f389..07f051ba5 100644
--- a/src/restic/repository/packer_manager.go
+++ b/src/restic/repository/packer_manager.go
@@ -3,7 +3,6 @@ package repository
 import (
 	"crypto/sha256"
 	"io"
-	"io/ioutil"
 	"os"
 	"restic"
 	"sync"
@@ -78,9 +77,9 @@ func (r *packerManager) findPacker(size uint) (packer *Packer, err error) {
 
 	// no suitable packer found, return new
 	debug.Log("create new pack for %d bytes", size)
-	tmpfile, err := ioutil.TempFile("", "restic-temp-pack-")
+	tmpfile, err := fs.TempFile("", "restic-temp-pack-")
 	if err != nil {
-		return nil, errors.Wrap(err, "ioutil.TempFile")
+		return nil, errors.Wrap(err, "fs.TempFile")
 	}
 
 	hw := hashing.NewWriter(tmpfile, sha256.New())
@@ -132,7 +131,7 @@ func (r *Repository) savePacker(p *Packer) error {
 		return errors.Wrap(err, "close tempfile")
 	}
 
-	err = fs.Remove(p.tmpfile.Name())
+	err = fs.RemoveIfExists(p.tmpfile.Name())
 	if err != nil {
 		return errors.Wrap(err, "Remove")
 	}
diff --git a/src/restic/repository/packer_manager_test.go b/src/restic/repository/packer_manager_test.go
index 37718a5ea..2ca44de0b 100644
--- a/src/restic/repository/packer_manager_test.go
+++ b/src/restic/repository/packer_manager_test.go
@@ -7,6 +7,7 @@ import (
 	"restic"
 	"restic/backend/mem"
 	"restic/crypto"
+	"restic/fs"
 	"restic/mock"
 	"testing"
 )
@@ -59,7 +60,7 @@ func saveFile(t testing.TB, be Saver, f *os.File, id restic.ID) {
 		t.Fatal(err)
 	}
 
-	if err := os.Remove(f.Name()); err != nil {
+	if err := fs.RemoveIfExists(f.Name()); err != nil {
 		t.Fatal(err)
 	}
 }
diff --git a/src/restic/repository/repack.go b/src/restic/repository/repack.go
index 7cd1c5fed..ef11034cb 100644
--- a/src/restic/repository/repack.go
+++ b/src/restic/repository/repack.go
@@ -3,11 +3,10 @@ package repository
 import (
 	"crypto/sha256"
 	"io"
-	"io/ioutil"
-	"os"
 	"restic"
 	"restic/crypto"
 	"restic/debug"
+	"restic/fs"
 	"restic/hashing"
 	"restic/pack"
 
@@ -25,7 +24,7 @@ func Repack(repo restic.Repository, packs restic.IDSet, keepBlobs restic.BlobSet
 		// load the complete pack into a temp file
 		h := restic.Handle{Type: restic.DataFile, Name: packID.String()}
 
-		tempfile, err := ioutil.TempFile("", "restic-temp-repack-")
+		tempfile, err := fs.TempFile("", "restic-temp-repack-")
 		if err != nil {
 			return errors.Wrap(err, "TempFile")
 		}
@@ -115,7 +114,7 @@ func Repack(repo restic.Repository, packs restic.IDSet, keepBlobs restic.BlobSet
 			return errors.Wrap(err, "Close")
 		}
 
-		if err = os.Remove(tempfile.Name()); err != nil {
+		if err = fs.RemoveIfExists(tempfile.Name()); err != nil {
 			return errors.Wrap(err, "Remove")
 		}
 		if p != nil {