NTLM tests: boost coverage by forcing the hostname

A shared library tests/libtest/.libs/lihostname.so is preloaded in NTLM
test-cases to override the system implementation of gethostname().  It
makes it possible to test the NTLM authentication for exact match, and
this way test the implementation of MD4 and DES.

If LD_PRELOAD doesn't work, a debug build willl also workk as debug
builds are now made to prefer a specific environment variable and will
then return that content as host name instead of the actual one.

Kamil wrote the bulk of this, Daniel Stenberg polished it.

1 files changed, 52 insertions, 0 deletions

diff --git a/lib/curl_gethostname.c b/lib/curl_gethostname.c
new file mode 100644
index 000000000..5a8c6494b
--- /dev/null
+++ b/lib/curl_gethostname.c
@@ -0,0 +1,52 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2010, 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 http://curl.haxx.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 "setup.h"
+#include "curl_gethostname.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define GETHOSTNAME_ENV_VAR "CURL_GETHOSTNAME"
+
+int Curl_gethostname(char *name, size_t namelen) {
+#ifdef HAVE_GETHOSTNAME
+
+#ifdef CURLDEBUG
+  /* we check the environment variable only in case of debug build */
+  const char *force_hostname = getenv(GETHOSTNAME_ENV_VAR);
+  if(force_hostname) {
+    strncpy(name, force_hostname, namelen);
+    return 0;
+  }
+#endif
+  /* no override requested */
+  return gethostname(name, namelen);
+
+#else
+  /* no gethostname() available on system, we should always fail */
+  (void) name;
+  (void) namelen;
+  return -1;
+#endif
+}