1 - always allocate the struct in protocol->setup_connection. Some
protocol handlers had to get this function added.

2 - always free at the end of a request. This is also an attempt to keep
less memory in the handle after it is completed.

Remove internal separated behavior of the easy vs multi intercace.
curl_easy_perform() is now using the multi interface itself.

Several minor multi interface quirks and bugs have been fixed in the
process.

Much help with debugging this has been provided by: Yang Tse

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 by other
intermixed commits, while renamed, and also by at least one
of the 6 commits this one reverts follows below. These 2 files
will exhibit a hole in history unless git's '--follow' option
is used when viewing logs.

  lib/curl_imap.h
  lib/curl_smtp.h

93 lib/*.c source files renamed to use our standard naming scheme.

This commit only does the file renaming.

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

  renamed:    lib/amigaos.c -> lib/curl_amigaos.c
  renamed:    lib/asyn-ares.c -> lib/curl_asyn_ares.c
  renamed:    lib/asyn-thread.c -> lib/curl_asyn_thread.c
  renamed:    lib/axtls.c -> lib/curl_axtls.c
  renamed:    lib/base64.c -> lib/curl_base64.c
  renamed:    lib/bundles.c -> lib/curl_bundles.c
  renamed:    lib/conncache.c -> lib/curl_conncache.c
  renamed:    lib/connect.c -> lib/curl_connect.c
  renamed:    lib/content_encoding.c -> lib/curl_content_encoding.c
  renamed:    lib/cookie.c -> lib/curl_cookie.c
  renamed:    lib/cyassl.c -> lib/curl_cyassl.c
  renamed:    lib/dict.c -> lib/curl_dict.c
  renamed:    lib/easy.c -> lib/curl_easy.c
  renamed:    lib/escape.c -> lib/curl_escape.c
  renamed:    lib/file.c -> lib/curl_file.c
  renamed:    lib/fileinfo.c -> lib/curl_fileinfo.c
  renamed:    lib/formdata.c -> lib/curl_formdata.c
  renamed:    lib/ftp.c -> lib/curl_ftp.c
  renamed:    lib/ftplistparser.c -> lib/curl_ftplistparser.c
  renamed:    lib/getenv.c -> lib/curl_getenv.c
  renamed:    lib/getinfo.c -> lib/curl_getinfo.c
  renamed:    lib/gopher.c -> lib/curl_gopher.c
  renamed:    lib/gtls.c -> lib/curl_gtls.c
  renamed:    lib/hash.c -> lib/curl_hash.c
  renamed:    lib/hmac.c -> lib/curl_hmac.c
  renamed:    lib/hostasyn.c -> lib/curl_hostasyn.c
  renamed:    lib/hostcheck.c -> lib/curl_hostcheck.c
  renamed:    lib/hostip.c -> lib/curl_hostip.c
  renamed:    lib/hostip4.c -> lib/curl_hostip4.c
  renamed:    lib/hostip6.c -> lib/curl_hostip6.c
  renamed:    lib/hostsyn.c -> lib/curl_hostsyn.c
  renamed:    lib/http.c -> lib/curl_http.c
  renamed:    lib/http_chunks.c -> lib/curl_http_chunks.c
  renamed:    lib/http_digest.c -> lib/curl_http_digest.c
  renamed:    lib/http_negotiate.c -> lib/curl_http_negotiate.c
  renamed:    lib/http_negotiate_sspi.c -> lib/curl_http_negotiate_sspi.c
  renamed:    lib/http_proxy.c -> lib/curl_http_proxy.c
  renamed:    lib/idn_win32.c -> lib/curl_idn_win32.c
  renamed:    lib/if2ip.c -> lib/curl_if2ip.c
  renamed:    lib/imap.c -> lib/curl_imap.c
  renamed:    lib/inet_ntop.c -> lib/curl_inet_ntop.c
  renamed:    lib/inet_pton.c -> lib/curl_inet_pton.c
  renamed:    lib/krb4.c -> lib/curl_krb4.c
  renamed:    lib/krb5.c -> lib/curl_krb5.c
  renamed:    lib/ldap.c -> lib/curl_ldap.c
  renamed:    lib/llist.c -> lib/curl_llist.c
  renamed:    lib/md4.c -> lib/curl_md4.c
  renamed:    lib/md5.c -> lib/curl_md5.c
  renamed:    lib/memdebug.c -> lib/curl_memdebug.c
  renamed:    lib/mprintf.c -> lib/curl_mprintf.c
  renamed:    lib/multi.c -> lib/curl_multi.c
  renamed:    lib/netrc.c -> lib/curl_netrc.c
  renamed:    lib/non-ascii.c -> lib/curl_non_ascii.c
  renamed:    lib/curl_non-ascii.h -> lib/curl_non_ascii.h
  renamed:    lib/nonblock.c -> lib/curl_nonblock.c
  renamed:    lib/nss.c -> lib/curl_nss.c
  renamed:    lib/nwlib.c -> lib/curl_nwlib.c
  renamed:    lib/nwos.c -> lib/curl_nwos.c
  renamed:    lib/openldap.c -> lib/curl_openldap.c
  renamed:    lib/parsedate.c -> lib/curl_parsedate.c
  renamed:    lib/pingpong.c -> lib/curl_pingpong.c
  renamed:    lib/polarssl.c -> lib/curl_polarssl.c
  renamed:    lib/pop3.c -> lib/curl_pop3.c
  renamed:    lib/progress.c -> lib/curl_progress.c
  renamed:    lib/qssl.c -> lib/curl_qssl.c
  renamed:    lib/rawstr.c -> lib/curl_rawstr.c
  renamed:    lib/rtsp.c -> lib/curl_rtsp.c
  renamed:    lib/security.c -> lib/curl_security.c
  renamed:    lib/select.c -> lib/curl_select.c
  renamed:    lib/sendf.c -> lib/curl_sendf.c
  renamed:    lib/share.c -> lib/curl_share.c
  renamed:    lib/slist.c -> lib/curl_slist.c
  renamed:    lib/smtp.c -> lib/curl_smtp.c
  renamed:    lib/socks.c -> lib/curl_socks.c
  renamed:    lib/socks_gssapi.c -> lib/curl_socks_gssapi.c
  renamed:    lib/socks_sspi.c -> lib/curl_socks_sspi.c
  renamed:    lib/speedcheck.c -> lib/curl_speedcheck.c
  renamed:    lib/splay.c -> lib/curl_splay.c
  renamed:    lib/ssh.c -> lib/curl_ssh.c
  renamed:    lib/sslgen.c -> lib/curl_sslgen.c
  renamed:    lib/ssluse.c -> lib/curl_ssluse.c
  renamed:    lib/strdup.c -> lib/curl_strdup.c
  renamed:    lib/strequal.c -> lib/curl_strequal.c
  renamed:    lib/strerror.c -> lib/curl_strerror.c
  renamed:    lib/strtok.c -> lib/curl_strtok.c
  renamed:    lib/strtoofft.c -> lib/curl_strtoofft.c
  renamed:    lib/telnet.c -> lib/curl_telnet.c
  renamed:    lib/tftp.c -> lib/curl_tftp.c
  renamed:    lib/timeval.c -> lib/curl_timeval.c
  renamed:    lib/transfer.c -> lib/curl_transfer.c
  renamed:    lib/url.c -> lib/curl_url.c
  renamed:    lib/version.c -> lib/curl_version.c
  renamed:    lib/warnless.c -> lib/curl_warnless.c
  renamed:    lib/wildcard.c -> lib/curl_wildcard.c

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

93 *.c source files renamed to use our standard naming scheme.

This change affects 77 files in libcurl's source tree.

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

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

Inclusion of top two most included header files now done in setup_once.h

Fixed checksrc warnings

Re-send ACK for block X in case we receive block X data again while
waiting for block X+1.

Based on an earlier patch by Marcin Adamski.

Since Curl_pgrsDone() itself calls Curl_pgrsUpdate() which may return an
abort instruction or similar we need to return that info back and
subsequently properly handle return codes from Curl_pgrsDone() where
used.

(Spotted by a Coverity scan)

Some functions using getaddrinfo and gethostbyname were still
mistakingly being used/linked even if c-ares was selected as resolver
backend.

Reported by: Arthur Murray
Bug: http://curl.haxx.se/mail/lib-2012-01/0160.html

By setting PROTOPT_NOURLQUERY in the protocol handler struct, the
protocol will get the "query part" of the URL cut off before the data is
handled by the protocol-specific code. This makes libcurl adhere to
RFC3986 section 2.2.

Test 1220 is added to verify a file:// URL with query-part.

After a PORT has been issued, and the multi handle would switch to the
CURLM_STATE_DO_MORE state (which is unique for FTP), libcurl would
return the wrong fdset to wait for when curl_multi_fdset() is
called. The code would blindly assume that it was waiting for a connect
of the second connection, while that isn't true immediately after the
PORT command.

Also, the function multi.c:domore_getsock() was highly FTP-centric and
therefore ugly to keep in protocol-agnostic code. I solved this problem
by introducing a new function pointer in the Curl_handler struct called
domore_getsock() which is only called during the DOMORE state for
protocols that set that pointer.

The new ftp.c:ftp_domore_getsock() function now returns fdset info about
the control connection's command/response handling while such a state is
in use, and goes over to waiting for a writable second connection first
once the commands are done.

The original problem could be seen by running test 525 and checking the
time stamps in the FTP server log. I can verify that this fix at least
fixes this problem.

Bug: http://curl.haxx.se/mail/lib-2011-10/0250.html
Reported by: Gokhan Sengun

Set ACK timeout to 5 seconds.

If we are waiting for block X and receive block Y that is the expected one, we
should send ACK and increase X (which is already implemented). Otherwise drop
the packet and don't increase retry counter.

It was mostly typecasted to int all over the code so switching to long
instead all over should be a net gain.

Add a 'readwrite' function to the protocol handler struct and use that
for the extra readwrite functionality RTSP needs.

"if(a)" is our style, not "if( a )"

By the use of a the new lib/checksrc.pl script that checks that our
basic source style rules are followed.

Found with codespell.

The PROT_* set of internal defines for the protocols is no longer
used. We now use the same bits internally as we have defined in the
public header using the CURLPROTO_ prefix. This is for simplicity and
because the PROT_* prefix was already used duplicated internally for a
set of KRB4 values.

The PROTOPT_* defines were moved up to just below the struct definition
within which they are used.

The protocol handler struct got a 'flags' field for special information
and characteristics of the given protocol.

This now enables us to move away central protocol information such as
CLOSEACTION and DUALCHANNEL from single defines in a central place, out
to each protocol's definition. It also made us stop abusing the protocol
field for other info than the protocol, and we could start cleaning up
other protocol-specific things by adding flags bits to set in the
handler struct.

The "protocol" field connectdata struct was removed as well and the code
now refers directly to the conn->handler->protocol field instead. To
make things work properly, the code now always store a conn->given
pointer that points out the original handler struct so that the code can
learn details from the original protocol even if conn->handler is
modified along the way - for example when switching to go over a HTTP
proxy.

As the function doesn't really use the connectdata struct but only the
SessionHanadle struct I modified what argument it wants.

It helps to prevent a hangup with some FTP servers in case idle session
timeout has exceeded.  But it may be useful also for other protocols
that send any quit message on disconnect.  Currently used by FTP, POP3,
IMAP and SMTP.

I found a bug in tftp_tx() in tftp.c. If a data resend is done after
reception of an ACK/OACK, the call to sendto is wrong.

Just made sure that the good old curl indentation style is used all over
this file.

tftpd-hpa has a bug where it will send an incorrect ack when the block
counter wraps and tftp options have been sent. Work around that by
accepting an ack for 65535 when we're expecting one for 0.

warning: conversion to 'long int' from 'time_t' may alter its value

... on win64 when time_t is 64bit and long is 32bit.

Curl_fillreadbuffer()'s second argument takes an int, so
typecasting to another is a bad idea.

Older unixes want an 'int' instead of 'size_t' as the 3rd
argumment so before this change it would cause warnings such as:

There is an implicit conversion from "unsigned long" to "int";
rounding, sign extension, or loss of accuracy may result.

Eric Mertens posted bug #3003705: when we made TFTP use the
correct timeout option when sent to the server (fixed May 18th
2010) it became obvious that libcurl used invalid timeout values
(300 by default while the RFC allows nothing above 255). While of
course it is obvious that as TFTP has worked thus far without
being able to set timeout at all, just removing the setting
wouldn't make any difference in behavior. I decided to still keep
it (but fix the problem) as it now actually allows for easier
(future) customization of the timeout.

(http://curl.haxx.se/bug/view.cgi?id=3003705)

If an unexpected block number was received, break out of the
switch loop.

In a normal expression, doing [unsigned short] + 1 will not wrap
at 16 bits so the comparisons and outputs were done wrong. I
added a macro do make sure it gets done right.

Douglas Kilpatrick filed bug report #3004787 about it:
http://curl.haxx.se/bug/view.cgi?id=3004787