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

4 files changed, 124 insertions, 2 deletions

diff --git a/tests/data/Makefile.inc b/tests/data/Makefile.inc
index 6762c8dcc..228e93d80 100644
--- a/tests/data/Makefile.inc
+++ b/tests/data/Makefile.inc
@@ -187,7 +187,7 @@ test1540 \
 \
 test1550 test1551 test1552 test1553 test1554 test1555 test1556 test1557 \
 test1558 test1559 test1560 test1561 test1562 test1563 test1564 test1565 \
-test1566 test1567 test1568 \
+test1566 test1567 test1568 test1569 \
 \
 test1590 test1591 test1592 test1593 test1594 test1595 test1596 \
 \
diff --git a/tests/data/test1569 b/tests/data/test1569
new file mode 100644
index 000000000..78f1dea26
--- /dev/null
+++ b/tests/data/test1569
@@ -0,0 +1,73 @@
+<testcase>
+<info>
+<keywords>
+FTP
+PASV
+RETR
+</keywords>
+</info>
+# Server-side
+<reply>
+<data nocheck="yes">
+data
+    to
+      see
+that FTP
+works
+  so does it?
+</data>
+<servercmd>
+REPLY EPSV 500 no such command
+</servercmd>
+</reply>
+
+# Client-side
+<client>
+<server>
+ftp
+</server>
+ <name>
+FTP first type=A then regular URL
+ </name>
+<tool>
+lib1569
+</tool>
+<command>
+"ftp://%HOSTIP:%FTPPORT/1569;type=A" ftp://%HOSTIP:%FTPPORT/1569
+</command>
+
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+<protocol>
+USER anonymous

+PASS ftp@example.com

+PWD

+EPSV

+PASV

+TYPE A

+RETR 1569

+PASV

+TYPE I

+SIZE 1569

+RETR 1569

+QUIT

+</protocol>
+</verify>
+<stdout>
+data
+    to
+      see
+that FTP
+works
+  so does it?
+data
+    to
+      see
+that FTP
+works
+  so does it?
+</stdout>
+
+</testcase>
diff --git a/tests/libtest/Makefile.inc b/tests/libtest/Makefile.inc
index 561895200..9f2ba8a91 100644
--- a/tests/libtest/Makefile.inc
+++ b/tests/libtest/Makefile.inc
@@ -57,7 +57,7 @@ noinst_PROGRAMS = chkhostname libauthretry libntlmconnect                \
  lib1534 lib1535 lib1536 lib1537 lib1538 lib1539 \
  lib1540         \
  lib1550 lib1551 lib1552 lib1553 lib1554 lib1555 lib1556 lib1557 \
- lib1558 lib1559 lib1560 lib1564 lib1565 lib1567 lib1568 \
+ lib1558 lib1559 lib1560 lib1564 lib1565 lib1567 lib1568 lib1569 \
  lib1591 lib1592 lib1593 lib1594 lib1596 \
          lib1905 lib1906 lib1907 lib1908 lib1910 lib1911 lib1912 lib1913 \
          lib1915 lib1916 lib1917 lib1918 lib1933 lib1934 lib1935 lib1936 \
@@ -608,6 +608,9 @@ lib1567_CPPFLAGS = $(AM_CPPFLAGS)
 lib1568_SOURCES = lib1568.c $(SUPPORTFILES)
 lib1568_CPPFLAGS = $(AM_CPPFLAGS)
 
+lib1569_SOURCES = lib1569.c $(SUPPORTFILES)
+lib1569_CPPFLAGS = $(AM_CPPFLAGS)
+
 lib1591_SOURCES = lib1591.c $(SUPPORTFILES) $(TESTUTIL) $(WARNLESS)
 lib1591_LDADD = $(TESTUTIL_LIBS)
 lib1591_CPPFLAGS = $(AM_CPPFLAGS) -DLIB1591
diff --git a/tests/libtest/lib1569.c b/tests/libtest/lib1569.c
new file mode 100644
index 000000000..0aaba3973
--- /dev/null
+++ b/tests/libtest/lib1569.c
@@ -0,0 +1,46 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+#include "test.h"
+
+#include "testtrace.h"
+#include "memdebug.h"
+
+int test(char *URL)
+{
+  CURLcode ret;
+  CURL *hnd;
+  curl_global_init(CURL_GLOBAL_ALL);
+
+  hnd = curl_easy_init();
+  curl_easy_setopt(hnd, CURLOPT_URL, URL);
+  curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_HEADER, 1L);
+
+  ret = curl_easy_perform(hnd);
+
+  curl_easy_setopt(hnd, CURLOPT_URL, libtest_arg2);
+  ret = curl_easy_perform(hnd);
+  curl_easy_cleanup(hnd);
+
+  curl_global_cleanup();
+  return (int)ret;
+}