Merge pull request #2303 from kolyshkin/minmax

Use min/max to simplify the code

pkg/chrootarchive/archive_test.go

@@ -496,10 +496,7 @@ type slowEmptyTarReader struct {
 // Read is a slow reader of an empty tar (like the output of "tar c --files-from /dev/null")
 func (s *slowEmptyTarReader) Read(p []byte) (int, error) {
 	time.Sleep(100 * time.Millisecond)
-	count := s.chunkSize
+	count := min(len(p), s.chunkSize)
-	if len(p) < s.chunkSize {
-		count = len(p)
-	}
 	for i := 0; i < count; i++ {
 		p[i] = 0
 	}

pkg/chunked/compressor/compressor.go

@@ -142,10 +142,7 @@ func (rc *rollingChecksumReader) Read(b []byte) (bool, int, error) {
 	rc.IsLastChunkZeros = false
 
 	if rc.pendingHole > 0 {
-		toCopy := int64(len(b))
+		toCopy := min(rc.pendingHole, int64(len(b)))
-		if rc.pendingHole < toCopy {
-			toCopy = rc.pendingHole
-		}
 		rc.pendingHole -= toCopy
 		for i := int64(0); i < toCopy; i++ {
 			b[i] = 0

pkg/chunked/storage_linux.go

@@ -698,18 +698,12 @@ func (c *chunkedDiffer) prepareCompressedStreamToFile(partCompression compressed
 
 // hashHole writes SIZE zeros to the specified hasher
 func hashHole(h hash.Hash, size int64, copyBuffer []byte) error {
-	count := int64(len(copyBuffer))
+	count := min(size, int64(len(copyBuffer)))
-	if size < count {
-		count = size
-	}
 	for i := int64(0); i < count; i++ {
 		copyBuffer[i] = 0
 	}
 	for size > 0 {
-		count = int64(len(copyBuffer))
+		count = min(size, int64(len(copyBuffer)))
-		if size < count {
-			count = size
-		}
 		if _, err := h.Write(copyBuffer[:count]); err != nil {
 			return err
 		}

pkg/ioutils/bytespipe.go

@@ -93,10 +93,7 @@ loop0:
 		}
 
 		// add new byte slice to the buffers slice and continue writing
-		nextCap := b.Cap() * 2
+		nextCap := min(b.Cap()*2, maxCap)
-		if nextCap > maxCap {
-			nextCap = maxCap
-		}
 		bp.buf = append(bp.buf, getBuffer(nextCap))
 	}
 	bp.wait.Broadcast()

userns.go

@@ -276,10 +276,7 @@ func (s *store) getAutoUserNS(options *types.AutoUserNsOptions, image *Image, rl
 	// bigger than s.autoNsMaxSize.
 	// This is a best effort heuristic.
 	if requestedSize == 0 {
-		size = initialSize
+		size = max(s.autoNsMinSize, initialSize)
-		if s.autoNsMinSize > size {
-			size = s.autoNsMinSize
-		}
 		if image != nil {
 			sizeFromImage, err := s.getMaxSizeFromImage(image, rlstore, lstores, options.PasswdFile, options.GroupFile)
 			if err != nil {