virStream*All: Preserve reported error

If one these four functions fail (virStreamRecvAll,
virStreamSendAll, virStreamSparseRecvAll, virStreamSparseSendAll)
the stream is aborted by calling virStreamAbort(). This is  a
public API; therefore, the first thing it does is error reset. At
that point any error that caused us to abort stream in the first
place is gone.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

src/libvirt-stream.c

@@ -616,7 +616,12 @@ virStreamSendAll(virStreamPtr stream,
     VIR_FREE(bytes);
 
     if (ret != 0) {
+        virErrorPtr orig_err = virSaveLastError();
         virStreamAbort(stream);
+        if (orig_err) {
+            virSetError(orig_err);
+            virFreeError(orig_err);
+        }
         virDispatchError(stream->conn);
     }
 
@@ -771,7 +776,12 @@ int virStreamSparseSendAll(virStreamPtr stream,
     VIR_FREE(bytes);
 
     if (ret != 0) {
+        virErrorPtr orig_err = virSaveLastError();
         virStreamAbort(stream);
+        if (orig_err) {
+            virSetError(orig_err);
+            virFreeError(orig_err);
+        }
         virDispatchError(stream->conn);
     }
 
@@ -865,7 +875,12 @@ virStreamRecvAll(virStreamPtr stream,
     VIR_FREE(bytes);
 
     if (ret != 0) {
+        virErrorPtr orig_err = virSaveLastError();
         virStreamAbort(stream);
+        if (orig_err) {
+            virSetError(orig_err);
+            virFreeError(orig_err);
+        }
         virDispatchError(stream->conn);
     }
 
@@ -985,7 +1000,12 @@ virStreamSparseRecvAll(virStreamPtr stream,
     VIR_FREE(bytes);
 
     if (ret != 0) {
+        virErrorPtr orig_err = virSaveLastError();
         virStreamAbort(stream);
+        if (orig_err) {
+            virSetError(orig_err);
+            virFreeError(orig_err);
+        }
         virDispatchError(stream->conn);
     }