ftp: add 'prefer_ascii' to the transfer state struct

... and make sure the code never updates 'set.prefer_ascii' as it breaks
handle reuse which should use the setting as the user specified it.

Added test 1569 to verify: it first makes an FTP transfer with ';type=A'
and then another without type on the same handle and the second should
then use binary. Previously, curl failed this.

Closes #6578

1 files changed, 6 insertions, 5 deletions

diff --git a/lib/transfer.c b/lib/transfer.c
index 2f29b29d8..4c82b89b8 100644
--- a/lib/transfer.c
+++ b/lib/transfer.c
@@ -286,7 +286,7 @@ CURLcode Curl_fillreadbuffer(struct Curl_easy *data, size_t bytes,
      *        <DATA> CRLF
      */
     /* On non-ASCII platforms the <DATA> may or may not be
-       translated based on set.prefer_ascii while the protocol
+       translated based on state.prefer_ascii while the protocol
        portion must always be translated to the network encoding.
        To further complicate matters, line end conversion might be
        done later on, so we need to prevent CRLFs from becoming
@@ -301,7 +301,7 @@ CURLcode Curl_fillreadbuffer(struct Curl_easy *data, size_t bytes,
 
     if(
 #ifdef CURL_DO_LINEEND_CONV
-       (data->set.prefer_ascii) ||
+       (data->state.prefer_ascii) ||
 #endif
        (data->set.crlf)) {
       /* \n will become \r\n later on */
@@ -348,7 +348,7 @@ CURLcode Curl_fillreadbuffer(struct Curl_easy *data, size_t bytes,
     {
       CURLcode result;
       size_t length;
-      if(data->set.prefer_ascii)
+      if(data->state.prefer_ascii)
         /* translate the protocol and data */
         length = nread;
       else
@@ -389,7 +389,7 @@ CURLcode Curl_fillreadbuffer(struct Curl_easy *data, size_t bytes,
       nread += strlen(endofline_network); /* for the added end of line */
   }
 #ifdef CURL_DOES_CONVERSIONS
-  else if((data->set.prefer_ascii) && (!sending_http_headers)) {
+  else if((data->state.prefer_ascii) && (!sending_http_headers)) {
     CURLcode result;
     result = Curl_convert_to_network(data, data->req.upload_fromhere, nread);
     /* Curl_convert_to_network calls failf if unsuccessful */
@@ -1028,7 +1028,7 @@ static CURLcode readwrite_upload(struct Curl_easy *data,
       if((!sending_http_headers) && (
 #ifdef CURL_DO_LINEEND_CONV
          /* always convert if we're FTPing in ASCII mode */
-         (data->set.prefer_ascii) ||
+         (data->state.prefer_ascii) ||
 #endif
          (data->set.crlf))) {
         /* Do we need to allocate a scratch buffer? */
@@ -1415,6 +1415,7 @@ CURLcode Curl_pretransfer(struct Curl_easy *data)
     }
   }
 
+  data->state.prefer_ascii = data->set.prefer_ascii;
   data->state.httpreq = data->set.method;
   data->change.url = data->set.str[STRING_SET_URL];