[Qemu-devel] [PATCH v2 4/9] ccid-card-passthru: Let the chardev::read() be more generic

[Philippe Mathieu-Daudé]

Suggested-by: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
---
 hw/usb/ccid-card-passthru.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/hw/usb/ccid-card-passthru.c b/hw/usb/ccid-card-passthru.c
index 0c44b38fc2..ba7c285ded 100644
--- a/hw/usb/ccid-card-passthru.c
+++ b/hw/usb/ccid-card-passthru.c
@@ -285,8 +285,14 @@ static void ccid_card_vscard_read(void *opaque, const 
uint8_t *buf, int size)
         card->vscard_in_hdr += hdr->length + sizeof(VSCMsgHeader);
         hdr = (VSCMsgHeader *)(card->vscard_in_data + card->vscard_in_hdr);
     }
-    if (card->vscard_in_hdr == card->vscard_in_pos) {
-        card->vscard_in_pos = card->vscard_in_hdr = 0;
+
+    /* Drop any messages that were fully processed.  */
+    if (card->vscard_in_hdr > 0) {
+        memmove(card->vscard_in_data,
+                card->vscard_in_data + card->vscard_in_hdr,
+                card->vscard_in_pos - card->vscard_in_hdr);
+        card->vscard_in_pos -= card->vscard_in_hdr;
+        card->vscard_in_hdr = 0;
     }
 }
 
-- 
2.20.1