- Try building a chain using issuers in the trusted store first to avoid
problems with server-sent legacy intermediates.

Prior to this change server-sent legacy intermediates with missing
legacy issuers would cause verification to fail even if the client's CA
bundle contained a valid replacement for the intermediate and an
alternate chain could be constructed that would verify successfully.

https://rt.openssl.org/Ticket/Display.html?id=3621&user=guest&pass=guest

ERR_error_string_n() was introduced in 0.9.6, no need to #ifdef anymore

Code for OpenSSL 0.9.4 serves no purpose anymore!

It was present for OpenSSL 0.9.5 code but we only support 0.9.7 or
later.

The existing callback served no purpose.

Prior to this change any-domain cookies (cookies without a domain that
are sent to any domain) were exported with domain name "unknown".

Bug: https://github.com/bagder/curl/issues/292

Bug: https://github.com/bagder/curl/pull/258#issuecomment-107915198
Reported-by: Gisle Vanem

Follow-up to e8423f9c with discussionis in
https://github.com/bagder/curl/pull/258

This check scans for fopen() with a mode string without 'b' present, as
it may indicate that an FOPEN_* define should rather be used.

- Change fopen calls to use FOPEN_READTEXT instead of "r" or "rt"
- Change fopen calls to use FOPEN_WRITETEXT instead of "w" or "wt"

This change is to explicitly specify when we need to read/write text.
Unfortunately 't' is not part of POSIX fopen so we can't specify it
directly. Instead we now have FOPEN_READTEXT, FOPEN_WRITETEXT.

Prior to this change we had an issue on Windows if an application that
uses libcurl overrides the default file mode to binary. The default file
mode in Windows is normally text mode (translation mode) and that's what
libcurl expects.

Bug: https://github.com/bagder/curl/pull/258#issuecomment-107093055
Reported-by: Orgad Shaneh

Bug: https://github.com/bagder/curl/issues/256

SSLv23_client_method is deprecated starting in OpenSSL 1.1.0. The
equivalent is TLS_client_method.

https://github.com/openssl/openssl/commit/13c9bb3#diff-708d3ae0f2c2973b272b811315381557

Previously, after seeing upgrade to HTTP/2, we feed data followed by
upgrade response headers directly to nghttp2_session_mem_recv() in
Curl_http2_switched().  But it turns out that passed buffer, mem, is
part of stream->mem, and callbacks called by
nghttp2_session_mem_recv() will write stream specific data into
stream->mem, overwriting input data.  This will corrupt input, and
most likely frame length error is detected by nghttp2 library.  The
fix is first copy the passed data to HTTP/2 connection buffer,
httpc->inbuf, and call nghttp2_session_mem_recv().

By (void) prefixing it and adding a comment. Did some minor related
cleanups.

Coverity CID 1299423.

Coverity CID 1299424 identified dead code because of checks that could
never equal true (if the mechanism's name was NULL).

Simplified the function by removing a level of pointers and removing the
loop and array that weren't used.

Replace use of assert with code that properly catches bad input at
run-time even in non-debug builds.

This flaw was sort of detected by Coverity CID 1299425 which claimed the
"case RTSPREQ_NONE" was dead code.

A failed calloc() would lead to NULL pointer use.

Coverity CID 1299427.

non-HTTP proxy implies not using CURLOPT_HTTPPROXYTUNNEL

Bug: http://curl.haxx.se/mail/lib-2015-05/0056.html
Reported-by: Sean Boudreau

Coverity CID 1299426 warned about possible NULL dereference otherwise,
but that would only ever happen if we get invalid HTTP/2 data with
frames for stream 0. Avoid this risk by returning early when stream 0 is
used.

Follow-up fix from b0143a2a

Detected by coverity. CID 1299429

This commit just add implicitly opened stream 1 to streams hash.

Prior to this change the description for SEC_E_ILLEGAL_MESSAGE was OS
and language specific, and invariably translated to something not very
helpful like: "The message received was unexpected or badly formatted."

Bug: https://github.com/bagder/curl/issues/267
Reported-by: Michael Osipov

Refer to b0143a2a for more information on the read-callback change.

With many easy handles using the same connection for multiplexing, it is
important we store and keep the transfer-oriented stuff in the
SessionHandle so that callbacks and callback data work fine even when
many easy handles share the same physical connection.

It makes them easier to match output from the nghttpd test server.

Previously, when we send all given buffer in data_source_callback, we
return NGHTTP2_ERR_DEFERRED, and nghttp2 library removes this stream
temporarily for writing.  This itself is good.  If this is the sole
stream in the session, nghttp2_session_want_write() returns zero,
which means that libcurl does not check writeability of the underlying
socket.  This leads to very slow upload, because it seems curl only
upload 16k something per 1 second.  To fix this, if we still have data
to send, call nghttp2_session_resume_data after nghttp2_session_send.
This makes nghttp2_session_want_write() returns nonzero (if connection
window still opens), and as a result, socket writeability is checked,
and upload speed becomes normal.

Stop curl from failing when non-fatal alert is received during
handshake.  This e.g. fixes lots of problems when working with https
sites through proxies.

BoringSSL removed support for direct callers of SSL_CTX_callback_ctrl
and SSL_CTX_ctrl, so move to a way that should work on BoringSSL and
OpenSSL.

re #275

Error: CLANG_WARNING:
lib/http.c:173:16: warning: Value stored to 'http' during its initialization is never read

Error: COMPILER_WARNING:
lib/http.c: scope_hint: In function ‘http_disconnect’
lib/http.c:173:16: warning: unused variable ‘http’ [-Wunused-variable]

.. also make __func__ replacement in multi.

Prior to this change debug builds would fail to build if the compiler
was building pre-c99 and didn't support __func__.

Use a curl_off_t for upload left

as after 4883f701, the *_clean() function only flushes the hash.