quiche: fix upload for bigger content-length

Signed-off-by: Jean-Philippe Menil <jpmenil@gmail.com>
Closes #8421

docs/KNOWN_BUGS

@@ -161,7 +161,6 @@ problems may have been fixed or changed somewhat since this was written.
  18.2 Uploading HTTP/3 files gets interrupted at certain file sizes
  18.4 Downloading with HTTP/3 produces broken files
  18.6 HTTP/3 multipart POST with quiche fails
- 18.7 HTTP/3 quiche upload large file fails
  18.8 HTTP/3 does not support client certs
  18.9 connection migration does not work
 
@@ -1135,10 +1134,6 @@ problems may have been fixed or changed somewhat since this was written.
 
  https://github.com/curl/curl/issues/7125
 
-18.7 HTTP/3 quiche upload large file fails
-
- https://github.com/curl/curl/issues/7532
-
 18.8 HTTP/3 does not support client certs
 
  aka "mutual authentication".

lib/vquic/quiche.c

@@ -701,7 +701,10 @@ static ssize_t h3_stream_send(struct Curl_easy *data,
     H3BUGF(infof(data, "Pass on %zd body bytes to quiche", len));
     sent = quiche_h3_send_body(qs->h3c, qs->conn, stream->stream3_id,
                                (uint8_t *)mem, len, FALSE);
-    if(sent < 0) {
+    if(sent == QUICHE_H3_ERR_DONE) {
+      sent = 0;
+    }
+    else if(sent < 0) {
       *curlcode = CURLE_SEND_ERROR;
       return -1;
     }