Doing curl_multi_add_handle() on an easy handle that is already added to
a multi handle now returns this error code. It previously returned
CURLM_BAD_EASY_HANDLE for this condition.

Start working on the next version and up some counters.

CURLOPT_XFERINFOFUNCTION is now the preferred progress callback function
and CURLOPT_PROGRESSFUNCTION is considered deprecated.

This new callback uses pure 'curl_off_t' arguments to pass on full
resolution sizes. It otherwise retains the same characteristics: the
same call rate, the same meanings for the arguments and the return code
is used the same way.

The progressfunc.c example is updated to show how to use the new
callback for newer libcurls while supporting the older one if built with
an older libcurl or even built with a newer libcurl while running with
an older.

Since we're adding new stuff, the next release will bump the minor
version and we're looking forward to 7.31.0

Introducing a number of options to the multi interface that
allows for multiple pipelines to the same host, in order to
optimize the balance between the penalty for opening new
connections and the potential pipelining latency.

Two new options for limiting the number of connections:

CURLMOPT_MAX_HOST_CONNECTIONS - Limits the number of running connections
to the same host. When adding a handle that exceeds this limit,
that handle will be put in a pending state until another handle is
finished, so we can reuse the connection.

CURLMOPT_MAX_TOTAL_CONNECTIONS - Limits the number of connections in total.
When adding a handle that exceeds this limit,
that handle will be put in a pending state until another handle is
finished. The free connection will then be reused, if possible, or
closed if the pending handle can't reuse it.

Several new options for pipelining:

CURLMOPT_MAX_PIPELINE_LENGTH - Limits the pipeling length. If a
pipeline is "full" when a connection is to be reused, a new connection
will be opened if the CURLMOPT_MAX_xxx_CONNECTIONS limits allow it.
If not, the handle will be put in a pending state until a connection is
ready (either free or a pipe got shorter).

CURLMOPT_CONTENT_LENGTH_PENALTY_SIZE - A pipelined connection will not
be reused if it is currently processing a transfer with a content
length that is larger than this.

CURLMOPT_CHUNK_LENGTH_PENALTY_SIZE - A pipelined connection will not
be reused if it is currently processing a chunk larger than this.

CURLMOPT_PIPELINING_SITE_BL - A blacklist of hosts that don't allow
pipelining.

CURLMOPT_PIPELINING_SERVER_BL - A blacklist of server types that don't allow
pipelining.

See the curl_multi_setopt() man page for details.

The flag can be used in pycurl-based applications where using the multi
interface would not be acceptable because of the performance lost caused
by implementing the select() loop in python.

Bug: http://curl.haxx.se/bug/view.cgi?id=1168
Downstream Bug: https://bugzilla.redhat.com/919127

No API change involved.

Info: http://curl.haxx.se/mail/lib-2013-02/0234.html

GCC specific adjustments:

- check __ILP32__ before 32 and 64bit processor architectures in
  order to detect ILP32 programming model on 64 bit processors
  which, of course, also support LP64 programming model, when using
  gcc 4.7 or newer.

- keep 32bit processor architecture checks in order to support gcc
  versions older than 4.7 which don't define __ILP32__

- check __LP64__ for gcc 3.3 and newer, while keeping 64bit processor
  architecture checks for older versions which don't define __LP64__

Bug: http://curl.haxx.se/bug/view.cgi?id=1205
Reported by: technion

The list of unsafe functions currently consists of sprintf, vsprintf,
strcat, strncat and gets.

Subsequently, some existing code needed updating to avoid warnings on
this.

This commit renames lib/setup.h to lib/curl_setup.h and
renames lib/setup_once.h to lib/curl_setup_once.h.

Removes the need and usage of a header inclusion guard foreign
to libcurl. [1]

Removes the need and presence of an alarming notice we carried
in old setup_once.h [2]

----------------------------------------

1 - lib/setup_once.h used __SETUP_ONCE_H macro as header inclusion guard
    up to commit ec691ca3 which changed this to HEADER_CURL_SETUP_ONCE_H,
    this single inclusion guard is enough to ensure that inclusion of
    lib/setup_once.h done from lib/setup.h is only done once.

    Additionally lib/setup.h has always used __SETUP_ONCE_H macro to
    protect inclusion of setup_once.h even after commit ec691ca3, this
    was to avoid a circular header inclusion triggered when building a
    c-ares enabled version with c-ares sources available which also has
    a setup_once.h header. Commit ec691ca3 exposes the real nature of
    __SETUP_ONCE_H usage in lib/setup.h, it is a header inclusion guard
    foreign to libcurl belonging to c-ares's setup_once.h

    The renaming this commit does, fixes the circular header inclusion,
    and as such removes the need and usage of a header inclusion guard
    foreign to libcurl. Macro __SETUP_ONCE_H no longer used in libcurl.

2 - Due to the circular interdependency of old lib/setup_once.h and the
    c-ares setup_once.h header, old file lib/setup_once.h has carried
    back from 2006 up to now days an alarming and prominent notice about
    the need of keeping libcurl's and c-ares's setup_once.h in sync.

    Given that this commit fixes the circular interdependency, the need
    and presence of mentioned notice is removed.

    All mentioned interdependencies come back from now old days when
    the c-ares project lived inside a curl subdirectory. This commit
    removes last traces of such fact.

This reverts renaming and usage of lib/*.h header files done
28-12-2012, reverting 2 commits:

  f871de00... build: make use of 76 lib/*.h renamed files
  ffd8e127... build: rename 76 lib/*.h files

This also reverts removal of redundant include guard (redundant thanks
to changes in above commits) done 2-12-2013, reverting 1 commit:

  c087374c... curl_setup.h: remove redundant include guard

This also reverts renaming and usage of lib/*.c source files done
3-12-2013, reverting 3 commits:

  13606bbf... build: make use of 93 lib/*.c renamed files
  5b6e7927... build: rename 93 lib/*.c files
  7d83dfff... build: commit 13606bbf follow-up 1

Start of related discussion thread:

  http://curl.haxx.se/mail/lib-2013-01/0012.html

Asking for confirmation on pushing this revertion commit:

  http://curl.haxx.se/mail/lib-2013-01/0048.html

Confirmation summary:

  http://curl.haxx.se/mail/lib-2013-01/0079.html

NOTICE: The list of 2 files that have been modified b...

76 private header files renamed to use our standard naming scheme.

This change affects 322 files in libcurl's source tree.

AIX sys/poll.h header file defines 'events' and 'revents' as C
preprocessor macros. Usage of these literals in libcurl's external
API was introduced in commit de24d7bd causing AIX build failures.
Appropriate inclusion of sys/poll.h by libcurl's external interface
fixes AIX build and usage issues while avoiding a SONAME bump.

Minor change to recently introduced function.  BC breaking, but since
curl_multi_wait() doesn't exist in any releases that should be fine.

/*
 * Name:     curl_multi_wait()
 *
 * Desc:     Poll on all fds within a CURLM set as well as any
 *           additional fds passed to the function.
 *
 * Returns:  CURLMcode type, general multi error code.
 */
CURL_EXTERN CURLMcode curl_multi_wait(CURLM *multi_handle,
                                      struct curl_waitfd extra_fds[],
                                      unsigned int extra_nfds,
                                      int timeout_ms);

CURLOPT_USE_SSL should be set to CURLUSESSL_* and nothing else in modern
libcurl versions.

For active FTP connections, applications may need setting the sockopt after accept() call returns successful. This fix gives a call to the callback registered with CURL_SOCKOPTFUNCTION option. Also a new sock type - CURLSOCKTYPE_ACCEPT - is added. This type is to be passed to application callbacks with - purpose - parameter. Applications may use this parameter to distinguish between socket types.

CURLSSH_AUTH_AGENT is a new auth type for SSH

I am about to merge the first patch that adds changes into the pending
release, and thus we bump the minor number.

Let's call it 7.27.1 for now, but it it probably going to become 7.28.0
when released.

Make sure CURL_VERSION_SSPI is present and works as in previous releases
for ABI and API compatibility reasons.

Added Windows SSPI version information to the curl version string when
SCHANNEL SSL is not enabled, as the version of the library should also
be included when SSPI is used to generate security contexts.

Removed SSPI from the feature list as the features are GSS-Negotiate,
NTLM and SSL depending on the usage of the SSPI library.

Due to new features

Info: http://curl.haxx.se/mail/lib-2012-04/0170.html

This protects from attribute names being defined by third party's code.

Improvement: http://curl.haxx.se/mail/lib-2012-04/0127.html

Configuration files such as curl_config.h and all config-*.h no longer exist
nor are generated/copied into 'src' directory, now these only exist in 'lib'
directory from where curl tool sources uses them.

Additionally old src/setup.h has been refactored into src/tool_setup.h which
now pulls lib/setup.h

The possibility of a makefile needing an include path adjustment exists.

As it turns out, some people do want that after all.