Reported-by: Frank Gevaerts

This change was made in CyaSSL/WolfSSL ver. 3.4.0

We prematurely changed protocol handler to HTTP/2 which made things very
slow (and wrong).

Reported-by: Stefan Eissing
Bug: https://github.com/bagder/curl/issues/169

Coverity CID 1288826

If a man page exists in the opts/ directory, it must also be referenced
either in curl_easy_setopt.3 or curl_multi_setopt.3

... if disabled at libcurl level.  Otherwise, we would allow to
negotiate NPN despite curl was invoked with the --no-npn option.

- Get rid of this flood of warnings in Windows mingw build:
warning: missing terminating " character

The warning is due to the carriage return. When msysgit checks out files
from the repo by default it converts the line endings to CRLF. Prior to
this change when mkhelp.pl processed the MANUAL and curl.1 in CRLF
format the trailing carriage returns caused unnecessary CR in the
output.

Using $< in a non-suffix rule context is a GNU make idiom.  This bug was
introduced in 7.41.0.

Reported-by: Stefan Eissing
Bug: https://github.com/bagder/curl/issues/169

Since we just started make use of free(NULL) in order to simplify code,
this change takes it a step further and:

- converts lots of Curl_safefree() calls to good old free()
- makes Curl_safefree() not check the pointer before free()

The (new) rule of thumb is: if you really want a function call that
frees a pointer and then assigns it to NULL, then use Curl_safefree().
But we will prefer just using free() from now on.

The following functions return immediately if a null pointer was passed.
* Curl_cookie_cleanup
* curl_formfree

It is therefore not needed that a function caller repeats a corresponding check.

This issue was fixed by using the software Coccinelle 1.0.0-rc24.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>

The function "free" is documented in the way that no action shall occur for
a passed null pointer. It is therefore not needed that a function caller
repeats a corresponding check.
http://stackoverflow.com/questions/18775608/free-a-null-pointer-anyway-or-check-first



This issue was fixed by using the software Coccinelle 1.0.0-rc24.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>

Bug: https://github.com/bagder/curl/pull/168

(trynextip)
- Don't try the "other" protocol family unless IPv6 is available. In an
IPv4-only build the other family can only be IPv6 which is unavailable.

This change essentially stops IPv4-only builds from attempting the
"happy eyeballs" secondary parallel connection that is supposed to be
used by the "other" address family.

Prior to this change in IPv4-only builds that secondary parallel
connection attempt could be erroneously used by the same family (IPv4)
which caused a bug where every address after the first for a host could
be tried twice, often in parallel. This change fixes that bug. An
example of the bug is shown below.

Assume MTEST resolves to 3 addresses 127.0.0.2, 127.0.0.3 and 127.0.0.4:

* STATE: INIT => CONNECT handle 0x64f4b0; line 1046 (connection #-5000)
* Rebuilt URL to: http://MTEST/
* Added connection 0. The cache now contains 1 members
* STATE: CONNECT => WAITRESOLVE handle 0x64f4b0; line 1083
(connection #0)
*   Trying 127.0.0.2...
* STATE: WAITRESOLVE => WAITCONNECT handle 0x64f4b0; line 1163
(connection #0)
*   Trying 127.0.0.3...
* connect to 127.0.0.2 port 80 failed: Connection refused
*   Trying 127.0.0.3...
* connect to 127.0.0.3 port 80 failed: Connection refused
*   Trying 127.0.0.4...
* connect to 127.0.0.3 port 80 failed: Connection refused
*   Trying 127.0.0.4...
* connect to 127.0.0.4 port 80 failed: Connection refused
* connect to 127.0.0.4 port 80 failed: Connection refused
* Failed to connect to MTEST port 80: Connection refused
* Closing connection 0
* The cache now contains 0 members
* Expire cleared
curl: (7) Failed to connect to MTEST port 80: Connection refused

The bug was born in commit bagder/curl@2d435c7.

In function Curl_closesocket() in connect.c the call to
Curl_multi_closed() was wrongly omitted if a socket close function
(CURLOPT_CLOSESOCKETFUNCTION) is registered.

That would lead to not removing the socket from the internal hash table
and not calling the multi socket callback appropriately.

Bug: http://curl.haxx.se/bug/view.cgi?id=1493

A signal handler for SIGALRM is installed in Curl_resolv_timeout. It is
configured to interrupt system calls and uses siglongjmp to return into
the function if alarm() goes off.

The signal handler is installed before curl_jmpenv is initialized.
This means that an already installed alarm timer could trigger the
newly installed signal handler, leading to undefined behavior when it
accesses the uninitialized curl_jmpenv.

Even if there is no previously installed alarm available, the code in
Curl_resolv_timeout itself installs an alarm before the environment is
fully set up. If the process is sent into suspend right after that, the
signal handler could be called too early as in previous scenario.

To fix this, the signal handler should only be installed and the alarm
timer only be set after sigsetjmp has been called.

... by using the regular Curl_http_done() method which checks for
that. This makes test 1801 fail consistently with error 56 (which seems
fine) to that test is also updated here.

Reported-by: Ben Darnell
Bug: https://github.com/bagder/curl/issues/166

Required for the test to work after a5d99494.