transfer: remove comments, add asserts

Curl_xfer_send and Curl_xfer_recv had commented FIXMEs about protocol
setting up the transfers badly, but in reality these functions are too
low-level to be able to depend on the protocol transfer setups having
been done yet. Removed.

The functions had checks for data and data->conn that I convered to
asserts since they SHOULD always be valid in this function. The same
goes for the runtime check for buffer_size > 0 that I also converted to
an assert since that should never be set to an invalid value.

Closes #14688

diff --git a/lib/transfer.c b/lib/transfer.c
index 489fd4fe89f2c1a1848fa4fad930739d6822bbb3..360dfd887ea9e3ffaa0e68cb2be236c897b2e4d4 100644 (file)
--- a/lib/transfer.c
+++ b/lib/transfer.c
@@ -1241,15 +1241,9 @@ CURLcode Curl_xfer_send(struct Curl_easy *data,
   CURLcode result;
   int sockindex;
 
-  if(!data || !data->conn)
-    return CURLE_FAILED_INIT;
-  /* FIXME: would like to enable this, but some protocols (MQTT) do not
-   * setup the transfer correctly, it seems
-  if(data->conn->writesockfd == CURL_SOCKET_BAD) {
-    failf(data, "transfer not setup for sending");
-    DEBUGASSERT(0);
-    return CURLE_SEND_ERROR;
-  } */
+  DEBUGASSERT(data);
+  DEBUGASSERT(data->conn);
+
   sockindex = ((data->conn->writesockfd != CURL_SOCKET_BAD) &&
                (data->conn->writesockfd == data->conn->sock[SECONDARYSOCKET]));
   result = Curl_conn_send(data, sockindex, buf, blen, eos, pnwritten);
@@ -1271,18 +1265,13 @@ CURLcode Curl_xfer_recv(struct Curl_easy *data,
 {
   int sockindex;
 
-  if(!data || !data->conn)
-    return CURLE_FAILED_INIT;
-  /* FIXME: would like to enable this, but some protocols (MQTT) do not
-   * setup the transfer correctly, it seems
-  if(data->conn->sockfd == CURL_SOCKET_BAD) {
-    failf(data, "transfer not setup for receiving");
-    DEBUGASSERT(0);
-    return CURLE_RECV_ERROR;
-  } */
+  DEBUGASSERT(data);
+  DEBUGASSERT(data->conn);
+  DEBUGASSERT(data->set.buffer_size > 0);
+
   sockindex = ((data->conn->sockfd != CURL_SOCKET_BAD) &&
                (data->conn->sockfd == data->conn->sock[SECONDARYSOCKET]));
-  if(data->set.buffer_size > 0 && (size_t)data->set.buffer_size < blen)
+  if((size_t)data->set.buffer_size < blen)
     blen = (size_t)data->set.buffer_size;
   return Curl_conn_recv(data, sockindex, buf, blen, pnrcvd);
 }