Add SSE-C tests for multipart, copy, get range operations (#941)

Makefile

@@ -3,10 +3,10 @@ all: checks
 checks:
 	@go get -t ./...
 	@go vet ./...
-	@SERVER_ENDPOINT=play.minio.io:9000 ACCESS_KEY=Q3AM3UQ867SPQQA43P2F SECRET_KEY=zuf+tfteSlswRu7BJ86wekitnifILbZam1KYY3TG ENABLE_HTTPS=1 go test -race -v ./...
+	@SERVER_ENDPOINT=play.minio.io:9000 ACCESS_KEY=Q3AM3UQ867SPQQA43P2F SECRET_KEY=zuf+tfteSlswRu7BJ86wekitnifILbZam1KYY3TG ENABLE_HTTPS=1 MINT_MODE=full go test -race -v ./...
 	@go get github.com/dustin/go-humanize/...
 	@go get github.com/sirupsen/logrus/...
-	@SERVER_ENDPOINT=play.minio.io:9000 ACCESS_KEY=Q3AM3UQ867SPQQA43P2F SECRET_KEY=zuf+tfteSlswRu7BJ86wekitnifILbZam1KYY3TG ENABLE_HTTPS=1 go run functional_tests.go
+	@SERVER_ENDPOINT=play.minio.io:9000 ACCESS_KEY=Q3AM3UQ867SPQQA43P2F SECRET_KEY=zuf+tfteSlswRu7BJ86wekitnifILbZam1KYY3TG ENABLE_HTTPS=1 MINT_MODE=full go run functional_tests.go
 	@mkdir -p /tmp/examples && for i in $(echo examples/s3/*); do go build -o /tmp/examples/$(basename ${i:0:-3}) ${i}; done
 	@go get -u github.com/a8m/mark/...
 	@go get -u github.com/minio/cli/...

api-get-object.go

@@ -127,6 +127,9 @@ func (c Client) getObjectWithContext(ctx context.Context, bucketName, objectName
 					} else {
 						// First request is a Stat or Seek call.
 						// Only need to run a StatObject until an actual Read or ReadAt request comes through.
+
+						// Remove range header if already set, for stat Operations to get original file size.
+						delete(opts.headers, "Range")
 						objectInfo, err = c.statObject(ctx, bucketName, objectName, StatObjectOptions{opts})
 						if err != nil {
 							resCh <- getResponse{
@@ -142,6 +145,8 @@ func (c Client) getObjectWithContext(ctx context.Context, bucketName, objectName
 						}
 					}
 				} else if req.settingObjectInfo { // Request is just to get objectInfo.
+					// Remove range header if already set, for stat Operations to get original file size.
+					delete(opts.headers, "Range")
 					if etag != "" {
 						opts.SetMatchETag(etag)
 					}
@@ -381,13 +386,11 @@ func (o *Object) Stat() (ObjectInfo, error) {
 
 	// This is the first request.
 	if !o.isStarted || !o.objectInfoSet {
-		statReq := getRequest{
+		// Send the request and get the response.
+		_, err := o.doGetRequest(getRequest{
 			isFirstReq:        !o.isStarted,
 			settingObjectInfo: !o.objectInfoSet,
-		}
-
-		// Send the request and get the response.
-		_, err := o.doGetRequest(statReq)
+		})
 		if err != nil {
 			o.prevErr = err
 			return ObjectInfo{}, err
@@ -493,7 +496,7 @@ func (o *Object) Seek(offset int64, whence int) (n int64, err error) {
 
 	// Negative offset is valid for whence of '2'.
 	if offset < 0 && whence != 2 {
-		return 0, ErrInvalidArgument(fmt.Sprintf("Negative position not allowed for %d.", whence))
+		return 0, ErrInvalidArgument(fmt.Sprintf("Negative position not allowed for %d", whence))
 	}
 
 	// This is the first request. So before anything else

api-stat.go

@@ -115,7 +115,7 @@ func (c Client) statObject(ctx context.Context, bucketName, objectName string, o
 		return ObjectInfo{}, err
 	}
 	if resp != nil {
-		if resp.StatusCode != http.StatusOK {
+		if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusPartialContent {
 			return ObjectInfo{}, httpRespToErrorResponse(resp, bucketName, objectName)
 		}
 	}