Vendor aws-sdk-go (dep ensure) (#178)

vendor/github.com/aws/aws-sdk-go/service/glacier/treehash_test.go

@@ -0,0 +1,63 @@
+package glacier_test
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"fmt"
+	"io"
+
+	"github.com/aws/aws-sdk-go/service/glacier"
+)
+
+func ExampleComputeHashes() {
+	r := testCreateReader()
+
+	h := glacier.ComputeHashes(r)
+	n, _ := r.Seek(0, 1) // Check position after checksumming
+
+	fmt.Printf("linear: %x\n", h.LinearHash)
+	fmt.Printf("tree: %x\n", h.TreeHash)
+	fmt.Printf("pos: %d\n", n)
+
+	// Output:
+	// linear: 68aff0c5a91aa0491752bfb96e3fef33eb74953804f6a2f7b708d5bcefa8ff6b
+	// tree: 154e26c78fd74d0c2c9b3cc4644191619dc4f2cd539ae2a74d5fd07957a3ee6a
+	// pos: 0
+}
+
+func testCreateReader() io.ReadSeeker {
+	buf := make([]byte, 5767168) // 5.5MB buffer
+	for i := range buf {
+		buf[i] = '0' // Fill with zero characters
+	}
+
+	return bytes.NewReader(buf)
+}
+
+func ExampleComputeTreeHash() {
+	r := testCreateReader()
+
+	const chunkSize = 1024 * 1024 // 1MB
+	buf := make([]byte, chunkSize)
+	hashes := [][]byte{}
+
+	for {
+		// Reach 1MB chunks from reader to generate hashes from
+		n, err := io.ReadAtLeast(r, buf, chunkSize)
+		if n == 0 {
+			break
+		}
+
+		tmpHash := sha256.Sum256(buf[:n])
+		hashes = append(hashes, tmpHash[:])
+		if err != nil {
+			break // last chunk
+		}
+	}
+
+	treeHash := glacier.ComputeTreeHash(hashes)
+	fmt.Printf("TreeHash: %x\n", treeHash)
+
+	// Output:
+	// TreeHash: 154e26c78fd74d0c2c9b3cc4644191619dc4f2cd539ae2a74d5fd07957a3ee6a
+}