c-ares with --enable-curldebug uses memdebug.h from libcurl's lib subdirectory.

memdebug.h needs access to libcurl's setup.h from libcurl's lib subdirectory
and also needs access to libcurl's generated curl_config.h

Undo old temporary change once used for testing purposes

  download was 0 bytes, as libcurl would then return the size as unknown (-1)
  and not 0. I wrote a fix and test case 566 to verify it.

Symbol hiding configure options renamed to the hopefully less ambiguous
--enable-symbol-hiding and --disable-symbol-hiding as well as related
macro names and some internal variables used for them.

Related configuration file preprocessor symbols named to
CARES_SYMBOL_HIDING and CARES_SYMBOL_SCOPE_EXTERN.

(http://curl.haxx.se/bug/view.cgi?id=2884561) but it seems to work for me...

  auth is used, as it caused a crash. I failed to repeat the issue, but still
  made a change that now forces the TCP connection used for a freed SCP
  session to get closed and not be re-used.

  POST using a read callback, with Digest authentication and
  "Transfer-Encoding: chunked" enforced.  I would then cause the first request
  to be wrongly sent and then basically hang until the server closed the
  connection. I fixed the problem and added test case 565 to verify it.

Fix two typos.

shows that this one is actually a modified copy of ares_parse_a_reply.c.

In order to comply with ares_parse_a_reply.c's M.I.T. license, the old
1998 M.I.T. copyright notice is now also preserved in this file the same
as it is done in other ares_parse_*.c files.

Fix identation of some license lines.

ares_parse_txt_reply() current version:

- Fixed a couple of potential double free's.

- Fixed memory leaks upon out of memory condition.

- Fixed pointer arithmetic.

- Setting ntxtreply to zero upon entry for all failure cases.

- Changed data type to size_t for variables substr_len, str_len and
  the length member of ares_txt_reply struct.

- Avoided a couple of memcpy() calls.

- Changed i data type to unsigned int to prevent compiler warnings.

- Adjusted a comment.

- Use ARES_SUCCESS literal for successfull completion.

- Added CVS Id tag.

dynamic and static c-ares libraries in debug and release flavours.

Additionally each of the three sample programs is built against
each of the four possible c-ares libraries, generating all this
a total number of 12 executables and 4 libraries.

MUST be valid and they are dereferenced further down in the function
unconditionally!

for Win32 and Symbian unless CARES_STATICLIB is defined to use static
library linkage.

false positive on a leaked socket, so this introduces a way to tell the system
that the socket is indeed closed without explicitly closing it!

based on the 'visibility' attribute for GNUC and __global for Sun
compilers, taking also in account __declspec function decoration
for Win32 and Symbian DLL's.

Introducing configure options --enable-hidden-symbols and
--disable-hidden-symbols following libcurl's naming.

  unparsable expiry dates and then treat them as session cookies - previously
  libcurl would reject cookies with a date format it couldn't parse. Research
  shows that the major browser treat such cookies as session cookies. I
  modified test 8 and 31 to verify this.