Revert changes relative to lib/*.[ch] recent renaming

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

  f871de0... build: make use of 76 lib/*.h renamed files
  ffd8e12... 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:

  c087374... 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:

  13606bb... build: make use of 93 lib/*.c renamed files
  5b6e792... build: rename 93 lib/*.c files
  7d83dff... build: commit 13606bbfde 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

1 files changed, 0 insertions, 139 deletions

diff --git a/lib/curl_pingpong.h b/lib/curl_pingpong.h
deleted file mode 100644
index 77060786a..000000000
--- a/lib/curl_pingpong.h
+++ /dev/null
@@ -1,139 +0,0 @@
-#ifndef HEADER_CURL_PINGPONG_H
-#define HEADER_CURL_PINGPONG_H
-/***************************************************************************
- *                                  _   _ ____  _
- *  Project                     ___| | | |  _ \| |
- *                             / __| | | | |_) | |
- *                            | (__| |_| |  _ <| |___
- *                             \___|\___/|_| \_\_____|
- *
- * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
- *
- * This software is licensed as described in the file COPYING, which
- * you should have received as part of this distribution. The terms
- * are also available at http://curl.haxx.se/docs/copyright.html.
- *
- * You may opt to use, copy, modify, merge, publish, distribute and/or sell
- * copies of the Software, and permit persons to whom the Software is
- * furnished to do so, under the terms of the COPYING file.
- *
- * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
- * KIND, either express or implied.
- *
- ***************************************************************************/
-
-#include "curl_setup.h"
-
-#if !defined(CURL_DISABLE_IMAP) || !defined(CURL_DISABLE_FTP) || \
-  !defined(CURL_DISABLE_POP3) || !defined(CURL_DISABLE_SMTP)
-#define USE_PINGPONG
-#endif
-
-/* forward-declaration, this is defined in curl_urldata.h */
-struct connectdata;
-
-/*
- * 'pingpong' is the generic struct used for protocols doing server<->client
- * conversations in a back-and-forth style such as FTP, IMAP, POP3, SMTP etc.
- *
- * It holds response cache and non-blocking sending data.
- */
-struct pingpong {
-  char *cache;     /* data cache between getresponse()-calls */
-  size_t cache_size;  /* size of cache in bytes */
-  size_t nread_resp;  /* number of bytes currently read of a server response */
-  char *linestart_resp; /* line start pointer for the server response
-                           reader function */
-  bool pending_resp;  /* set TRUE when a server response is pending or in
-                         progress, and is cleared once the last response is
-                         read */
-  char *sendthis; /* allocated pointer to a buffer that is to be sent to the
-                     server */
-  size_t sendleft; /* number of bytes left to send from the sendthis buffer */
-  size_t sendsize; /* total size of the sendthis buffer */
-  struct timeval response; /* set to Curl_tvnow() when a command has been sent
-                              off, used to time-out response reading */
-  long response_time; /* When no timeout is given, this is the amount of
-                         milliseconds we await for a server response. */
-
-  struct connectdata *conn; /* points to the connectdata struct that this
-                               belongs to */
-
-  /* Function pointers the protocols MUST implement and provide for the
-     pingpong layer to function */
-
-  CURLcode (*statemach_act)(struct connectdata *conn);
-
-  int (*endofresp)(struct pingpong *pp, int *code);
-};
-
-/*
- * Curl_pp_multi_statemach()
- *
- * called repeatedly until done when the multi interface is used.
- */
-CURLcode Curl_pp_multi_statemach(struct pingpong *pp);
-
-/*
- * Curl_pp_easy_statemach()
- *
- * called repeatedly until done when the easy interface is used.
- */
-CURLcode Curl_pp_easy_statemach(struct pingpong *pp);
-
-
-/* initialize stuff to prepare for reading a fresh new response */
-void Curl_pp_init(struct pingpong *pp);
-
-/* Returns timeout in ms. 0 or negative number means the timeout has already
-   triggered */
-long Curl_pp_state_timeout(struct pingpong *pp);
-
-
-/***********************************************************************
- *
- * Curl_pp_sendf()
- *
- * Send the formated string as a command to a pingpong server. Note that
- * the string should not have any CRLF appended, as this function will
- * append the necessary things itself.
- *
- * made to never block
- */
-CURLcode Curl_pp_sendf(struct pingpong *pp,
-                       const char *fmt, ...);
-
-/***********************************************************************
- *
- * Curl_pp_vsendf()
- *
- * Send the formated string as a command to a pingpong server. Note that
- * the string should not have any CRLF appended, as this function will
- * append the necessary things itself.
- *
- * made to never block
- */
-CURLcode Curl_pp_vsendf(struct pingpong *pp,
-                        const char *fmt,
-                        va_list args);
-
-/*
- * Curl_pp_readresp()
- *
- * Reads a piece of a server response.
- */
-CURLcode Curl_pp_readresp(curl_socket_t sockfd,
-                          struct pingpong *pp,
-                          int *code, /* return the server code if done */
-                          size_t *size); /* size of the response */
-
-
-CURLcode Curl_pp_flushsend(struct pingpong *pp);
-
-/* call this when a pingpong connection is disconnected */
-CURLcode Curl_pp_disconnect(struct pingpong *pp);
-
-int Curl_pp_getsock(struct pingpong *pp, curl_socket_t *socks,
-                    int numsocks);
-
-#endif /* HEADER_CURL_PINGPONG_H */