*: add more IO error checks

plumbing/format/packfile/common.go

@@ -4,6 +4,7 @@ import (
 	"io"
 
 	"gopkg.in/src-d/go-git.v4/plumbing/storer"
+	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 )
 
 var signature = []byte{'P', 'A', 'C', 'K'}
@@ -24,14 +25,7 @@ const (
 // packfile.
 func UpdateObjectStorage(s storer.EncodedObjectStorer, packfile io.Reader) error {
 	if sw, ok := s.(storer.PackfileWriter); ok {
-		w, err := sw.PackfileWriter()
-		if err != nil {
-			return err
-		}
-
-		defer w.Close()
-		_, err = io.Copy(w, packfile)
-		return err
+		return writePackfileToObjectStorage(sw, packfile)
 	}
 
 	stream := NewScanner(packfile)
@@ -43,3 +37,15 @@ func UpdateObjectStorage(s storer.EncodedObjectStorer, packfile io.Reader) error
 	_, err = d.Decode()
 	return err
 }
+
+func writePackfileToObjectStorage(sw storer.PackfileWriter, packfile io.Reader) error {
+	var err error
+	w, err := sw.PackfileWriter()
+	if err != nil {
+		return err
+	}
+
+	defer ioutil.CheckClose(w, &err)
+	_, err = io.Copy(w, packfile)
+	return err
+}

plumbing/format/packfile/scanner.go

@@ -8,10 +8,11 @@ import (
 	"hash"
 	"hash/crc32"
 	"io"
-	"io/ioutil"
+	stdioutil "io/ioutil"
 
 	"gopkg.in/src-d/go-git.v4/plumbing"
 	"gopkg.in/src-d/go-git.v4/utils/binary"
+	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 )
 
 var (
@@ -198,7 +199,7 @@ func (s *Scanner) discardObjectIfNeeded() error {
 	}
 
 	h := s.pendingObject
-	n, _, err := s.NextObject(ioutil.Discard)
+	n, _, err := s.NextObject(stdioutil.Discard)
 	if err != nil {
 		return err
 	}
@@ -275,8 +276,7 @@ func (s *Scanner) NextObject(w io.Writer) (written int64, crc32 uint32, err erro
 
 // ReadRegularObject reads and write a non-deltified object
 // from it zlib stream in an object entry in the packfile.
-func (s *Scanner) copyObject(w io.Writer) (int64, error) {
-	var err error
+func (s *Scanner) copyObject(w io.Writer) (n int64, err error) {
 	if s.zr == nil {
 		zr, err := zlib.NewReader(s.r)
 		if err != nil {
@@ -290,14 +290,9 @@ func (s *Scanner) copyObject(w io.Writer) (int64, error) {
 		}
 	}
 
-	defer func() {
-		closeErr := s.zr.Close()
-		if err == nil {
-			err = closeErr
-		}
-	}()
-
-	return io.Copy(w, s.zr)
+	defer ioutil.CheckClose(s.zr, &err)
+	n, err = io.Copy(w, s.zr)
+	return
 }
 
 // SeekFromStart sets a new offset from start, returns the old position before
@@ -329,7 +324,7 @@ func (s *Scanner) Checksum() (plumbing.Hash, error) {
 
 // Close reads the reader until io.EOF
 func (s *Scanner) Close() error {
-	_, err := io.Copy(ioutil.Discard, s.r)
+	_, err := io.Copy(stdioutil.Discard, s.r)
 	return err
 }
 

storage/filesystem/config.go

@@ -1,11 +1,12 @@
 package filesystem
 
 import (
-	"io/ioutil"
+	stdioutil "io/ioutil"
 	"os"
 
 	"gopkg.in/src-d/go-git.v4/config"
 	"gopkg.in/src-d/go-git.v4/storage/filesystem/internal/dotgit"
+	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 )
 
 type ConfigStorage struct {
@@ -24,9 +25,9 @@ func (c *ConfigStorage) Config() (*config.Config, error) {
 		return nil, err
 	}
 
-	defer f.Close()
+	defer ioutil.CheckClose(f, &err)
 
-	b, err := ioutil.ReadAll(f)
+	b, err := stdioutil.ReadAll(f)
 	if err != nil {
 		return nil, err
 	}
@@ -35,7 +36,7 @@ func (c *ConfigStorage) Config() (*config.Config, error) {
 		return nil, err
 	}
 
-	return cfg, nil
+	return cfg, err
 }
 
 func (c *ConfigStorage) SetConfig(cfg *config.Config) error {
@@ -48,7 +49,7 @@ func (c *ConfigStorage) SetConfig(cfg *config.Config) error {
 		return err
 	}
 
-	defer f.Close()
+	defer ioutil.CheckClose(f, &err)
 
 	b, err := cfg.Marshal()
 	if err != nil {

storage/filesystem/index.go

@@ -5,6 +5,7 @@ import (
 
 	"gopkg.in/src-d/go-git.v4/plumbing/format/index"
 	"gopkg.in/src-d/go-git.v4/storage/filesystem/internal/dotgit"
+	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 )
 
 type IndexStorage struct {
@@ -17,10 +18,11 @@ func (s *IndexStorage) SetIndex(idx *index.Index) error {
 		return err
 	}
 
-	defer f.Close()
+	defer ioutil.CheckClose(f, &err)
 
 	e := index.NewEncoder(f)
-	return e.Encode(idx)
+	err = e.Encode(idx)
+	return err
 }
 
 func (s *IndexStorage) Index() (*index.Index, error) {
@@ -37,8 +39,9 @@ func (s *IndexStorage) Index() (*index.Index, error) {
 		return nil, err
 	}
 
-	defer f.Close()
+	defer ioutil.CheckClose(f, &err)
 
 	d := index.NewDecoder(f)
-	return idx, d.Decode(idx)
+	err = d.Decode(idx)
+	return idx, err
 }

storage/filesystem/internal/dotgit/dotgit.go

@@ -253,10 +253,10 @@ func (d *DotGit) SetRef(r *plumbing.Reference) error {
 		return err
 	}
 
-	if _, err := f.Write([]byte(content)); err != nil {
-		return err
-	}
-	return f.Close()
+	defer ioutil.CheckClose(f, &err)
+
+	_, err = f.Write([]byte(content))
+	return err
 }
 
 // Refs scans the git directory collecting references, which it returns.

storage/filesystem/internal/dotgit/writers_test.go

@@ -12,6 +12,7 @@ import (
 
 	. "gopkg.in/check.v1"
 	"gopkg.in/src-d/go-billy.v3/osfs"
+	"gopkg.in/src-d/go-git.v4/plumbing/format/packfile"
 )
 
 func (s *SuiteDotGit) TestNewObjectPack(c *C) {
@@ -35,13 +36,30 @@ func (s *SuiteDotGit) TestNewObjectPack(c *C) {
 
 	c.Assert(w.Close(), IsNil)
 
-	stat, err := fs.Stat(fmt.Sprintf("objects/pack/pack-%s.pack", f.PackfileHash))
+	pfPath := fmt.Sprintf("objects/pack/pack-%s.pack", f.PackfileHash)
+	idxPath := fmt.Sprintf("objects/pack/pack-%s.idx", f.PackfileHash)
+
+	stat, err := fs.Stat(pfPath)
 	c.Assert(err, IsNil)
 	c.Assert(stat.Size(), Equals, int64(84794))
 
-	stat, err = fs.Stat(fmt.Sprintf("objects/pack/pack-%s.idx", f.PackfileHash))
+	stat, err = fs.Stat(idxPath)
 	c.Assert(err, IsNil)
 	c.Assert(stat.Size(), Equals, int64(1940))
+
+	pf, err := fs.Open(pfPath)
+	c.Assert(err, IsNil)
+	pfs := packfile.NewScanner(pf)
+	_, objects, err := pfs.Header()
+	c.Assert(err, IsNil)
+	for i := uint32(0); i < objects; i++ {
+		_, err := pfs.NextObjectHeader()
+		if err != nil {
+			c.Assert(err, IsNil)
+			break
+		}
+	}
+	c.Assert(pfs.Close(), IsNil)
 }
 
 func (s *SuiteDotGit) TestNewObjectPackUnused(c *C) {
@@ -63,6 +81,12 @@ func (s *SuiteDotGit) TestNewObjectPackUnused(c *C) {
 	info, err := fs.ReadDir("objects/pack")
 	c.Assert(err, IsNil)
 	c.Assert(info, HasLen, 0)
+
+	// check clean up of temporary files
+	info, err = fs.ReadDir("")
+	for _, fi := range info {
+		c.Assert(fi.IsDir(), Equals, true)
+	}
 }
 
 func (s *SuiteDotGit) TestSyncedReader(c *C) {

storage/filesystem/object.go

@@ -11,6 +11,7 @@ import (
 	"gopkg.in/src-d/go-git.v4/plumbing/storer"
 	"gopkg.in/src-d/go-git.v4/storage/filesystem/internal/dotgit"
 	"gopkg.in/src-d/go-git.v4/storage/memory"
+	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 
 	"gopkg.in/src-d/go-billy.v3"
 )
@@ -53,10 +54,11 @@ func (s *ObjectStorage) loadIdxFile(h plumbing.Hash) error {
 	if err != nil {
 		return err
 	}
-	defer idxfile.Close()
 
+	defer ioutil.CheckClose(idxfile, &err)
 	s.index[h] = make(idx)
-	return s.index[h].Decode(idxfile)
+	err = s.index[h].Decode(idxfile)
+	return err
 }
 
 func (s *ObjectStorage) NewEncodedObject() plumbing.EncodedObject {
@@ -94,14 +96,14 @@ func (s *ObjectStorage) SetEncodedObject(o plumbing.EncodedObject) (plumbing.Has
 		return plumbing.ZeroHash, err
 	}
 
-	defer ow.Close()
+	defer ioutil.CheckClose(ow, &err)
 
 	or, err := o.Reader()
 	if err != nil {
 		return plumbing.ZeroHash, err
 	}
 
-	defer or.Close()
+	defer ioutil.CheckClose(or, &err)
 
 	if err := ow.WriteHeader(o.Type(), o.Size()); err != nil {
 		return plumbing.ZeroHash, err
@@ -111,7 +113,7 @@ func (s *ObjectStorage) SetEncodedObject(o plumbing.EncodedObject) (plumbing.Has
 		return plumbing.ZeroHash, err
 	}
 
-	return o.Hash(), nil
+	return o.Hash(), err
 }
 
 // EncodedObject returns the object with the given hash, by searching for it in
@@ -143,15 +145,15 @@ func (s *ObjectStorage) getFromUnpacked(h plumbing.Hash) (obj plumbing.EncodedOb
 		return nil, err
 	}
 
-	defer f.Close()
+	defer ioutil.CheckClose(f, &err)
 
 	obj = s.NewEncodedObject()
 	r, err := objfile.NewReader(f)
 	if err != nil {
 		return nil, err
 	}
 
-	defer r.Close()
+	defer ioutil.CheckClose(r, &err)
 
 	t, size, err := r.Header()
 	if err != nil {
@@ -186,7 +188,7 @@ func (s *ObjectStorage) getFromPackfile(h plumbing.Hash) (plumbing.EncodedObject
 		return nil, err
 	}
 
-	defer f.Close()
+	defer ioutil.CheckClose(f, &err)
 
 	p := packfile.NewScanner(f)
 	d, err := packfile.NewDecoder(p, memory.NewStorage())
@@ -195,7 +197,8 @@ func (s *ObjectStorage) getFromPackfile(h plumbing.Hash) (plumbing.EncodedObject
 	}
 
 	d.SetOffsets(s.index[pack])
-	return d.DecodeObjectAt(offset)
+	obj, err := d.DecodeObjectAt(offset)
+	return obj, err
 }
 
 func (s *ObjectStorage) findObjectInPackfile(h plumbing.Hash) (plumbing.Hash, int64) {

storage/filesystem/shallow.go

@@ -6,6 +6,7 @@ import (
 
 	"gopkg.in/src-d/go-git.v4/plumbing"
 	"gopkg.in/src-d/go-git.v4/storage/filesystem/internal/dotgit"
+	"gopkg.in/src-d/go-git.v4/utils/ioutil"
 )
 
 // ShallowStorage where the shallow commits are stored, an internal to
@@ -23,14 +24,14 @@ func (s *ShallowStorage) SetShallow(commits []plumbing.Hash) error {
 		return err
 	}
 
-	defer f.Close()
+	defer ioutil.CheckClose(f, &err)
 	for _, h := range commits {
 		if _, err := fmt.Fprintf(f, "%s\n", h); err != err {
 			return err
 		}
 	}
 
-	return nil
+	return err
 }
 
 // Shallow return the shallow commits reading from shallo file from .git

storage/filesystem/storage_test.go

@@ -26,6 +26,7 @@ func (s *StorageSuite) SetUpTest(c *C) {
 	c.Assert(err, IsNil)
 
 	s.BaseStorageSuite = test.NewBaseStorageSuite(storage)
+	s.BaseStorageSuite.SetUpTest(c)
 }
 
 func (s *StorageSuite) TestFilesystem(c *C) {

storage/memory/storage_test.go

@@ -17,4 +17,5 @@ var _ = Suite(&StorageSuite{})
 
 func (s *StorageSuite) SetUpTest(c *C) {
 	s.BaseStorageSuite = test.NewBaseStorageSuite(NewStorage())
+	s.BaseStorageSuite.SetUpTest(c)
 }