test766: verify CURLOPT_SOCKOPTFUNCTION error on accept

This test does active FTP with a socketopt callback that returns error
for the CURLSOCKTYPE_ACCEPT "purpose" to make sure we test and exercise
this error path - without leaks.

tests/data/Makefile.am

@@ -109,7 +109,7 @@ test727 test728 test729 test730 test731 test732 test733 test734 test735 \
 test736 test737 test738 test739 test740 test741 test742 test743 test744 \
 test745 test746 test747 test748 test749 test750 test751 test752 test753 \
 test754 test755 test756 test757 test758 test759 test760 test761 test762 \
-test763 test764 test765 \
+test763 test764 test765 test766 \
 \
 test780 test781 test782 test783 test784 test785 test786 test787 test788 \
 test789 test790 test791 test792 test793 test794         test796 test797 \

tests/data/test766

@@ -0,0 +1,54 @@
+<testcase>
+<info>
+<keywords>
+FTP
+PORT
+CURLOPT_SOCKOPTFUNCTION
+</keywords>
+</info>
+
+# Server-side
+<reply>
+<data nocheck="yes">
+hello
+</data>
+</reply>
+
+# Client-side
+<client>
+<server>
+ftp
+</server>
+<tool>
+lib%TESTNUMBER
+</tool>
+<name>
+FTP PORT with sockopt callback refusing the accept
+</name>
+<command>
+ftp://%HOSTIP:%FTPPORT/path/%TESTNUMBER
+</command>
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+# Strip off parts of the PORT and EPRT commands that might differ
+<strippart>
+s/^PORT (.*)/PORT/
+s/^EPRT \|1\|(.*)/EPRT \|1\|/
+</strippart>
+<protocol>
+USER anonymous
+PASS ftp@example.com
+PWD
+CWD path
+EPRT |1|
+</protocol>
+
+# 42 == CURLE_ABORTED_BY_CALLBACK
+<errorcode>
+42
+</errorcode>
+
+</verify>
+</testcase>

tests/libtest/Makefile.inc

@@ -76,6 +76,7 @@ TESTS_C = \
   lib694.c lib695.c \
   lib751.c          lib753.c                                     lib758.c \
   lib757.c \
+  lib766.c \
   lib1156.c \
   lib1301.c                                                   lib1308.c \
   lib1485.c \

tests/libtest/lib766.c

@@ -0,0 +1,127 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 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.
+ *
+ * SPDX-License-Identifier: curl
+ *
+ ***************************************************************************/
+
+#include "first.h"
+
+#include "memdebug.h"
+
+static int sockopt_766(void *clientp,
+                       curl_socket_t curlfd,
+                       curlsocktype purpose)
+{
+  (void)clientp;
+  (void)curlfd;
+  if(purpose == CURLSOCKTYPE_ACCEPT) {
+    curl_mfprintf(stderr,
+                  "Return error from CURLOPT_SOCKOPTFUNCTION callback\n");
+    return 1; /* force error */
+  }
+  return 0;
+}
+
+static CURLcode test_lib766(const char *URL)
+{
+  CURL *easy = NULL;
+  CURLM *multi = NULL;
+  CURLcode res = CURLE_OK;
+  int running;
+  int msgs_left;
+  CURLMsg *msg;
+
+  start_test_timing();
+
+  res_global_init(CURL_GLOBAL_ALL);
+  if(res) {
+    return res;
+  }
+
+  easy_init(easy);
+  easy_setopt(easy, CURLOPT_VERBOSE, 1L);
+  easy_setopt(easy, CURLOPT_URL, URL);
+  easy_setopt(easy, CURLOPT_FTPPORT, "-");
+  easy_setopt(easy, CURLOPT_SOCKOPTFUNCTION, sockopt_766);
+
+  multi_init(multi);
+
+  multi_add_handle(multi, easy);
+
+  for(;;) {
+    struct timeval interval;
+    fd_set fdread;
+    fd_set fdwrite;
+    fd_set fdexcep;
+    long timeout = -99;
+    int maxfd = -99;
+
+    multi_perform(multi, &running);
+
+    abort_on_test_timeout();
+
+    if(!running)
+      break; /* done */
+
+    FD_ZERO(&fdread);
+    FD_ZERO(&fdwrite);
+    FD_ZERO(&fdexcep);
+
+    multi_fdset(multi, &fdread, &fdwrite, &fdexcep, &maxfd);
+
+    /* At this point, maxfd is guaranteed to be greater or equal than -1. */
+
+    multi_timeout(multi, &timeout);
+
+    /* At this point, timeout is guaranteed to be greater or equal than -1. */
+
+    if(timeout != -1L) {
+      int itimeout;
+#if LONG_MAX > INT_MAX
+      itimeout = (timeout > (long)INT_MAX) ? INT_MAX : (int)timeout;
+#else
+      itimeout = (int)timeout;
+#endif
+      interval.tv_sec = itimeout/1000;
+      interval.tv_usec = (itimeout%1000)*1000;
+    }
+    else {
+      interval.tv_sec = 0;
+      interval.tv_usec = 100000L; /* 100 ms */
+    }
+
+    select_test(maxfd + 1, &fdread, &fdwrite, &fdexcep, &interval);
+
+    abort_on_test_timeout();
+  }
+
+  msg = curl_multi_info_read(multi, &msgs_left);
+  if(msg)
+    res = msg->data.result;
+
+test_cleanup:
+
+  curl_multi_cleanup(multi);
+  curl_easy_cleanup(easy);
+  curl_global_cleanup();
+
+  return res;
+}