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, 108 insertions, 0 deletions

diff --git a/lib/select.h b/lib/select.h
new file mode 100644
index 000000000..d66873fe9
--- /dev/null
+++ b/lib/select.h
@@ -0,0 +1,108 @@
+#ifndef HEADER_CURL_SELECT_H
+#define HEADER_CURL_SELECT_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2012, 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 "setup.h"
+
+#ifdef HAVE_SYS_POLL_H
+#include <sys/poll.h>
+#elif defined(HAVE_POLL_H)
+#include <poll.h>
+#endif
+
+/*
+ * Definition of pollfd struct and constants for platforms lacking them.
+ */
+
+#if !defined(HAVE_STRUCT_POLLFD) && \
+    !defined(HAVE_SYS_POLL_H) && \
+    !defined(HAVE_POLL_H)
+
+#define POLLIN      0x01
+#define POLLPRI     0x02
+#define POLLOUT     0x04
+#define POLLERR     0x08
+#define POLLHUP     0x10
+#define POLLNVAL    0x20
+
+struct pollfd
+{
+    curl_socket_t fd;
+    short   events;
+    short   revents;
+};
+
+#endif
+
+#ifndef POLLRDNORM
+#define POLLRDNORM POLLIN
+#endif
+
+#ifndef POLLWRNORM
+#define POLLWRNORM POLLOUT
+#endif
+
+#ifndef POLLRDBAND
+#define POLLRDBAND POLLPRI
+#endif
+
+/* there are three CSELECT defines that are defined in the public header that
+   are exposed to users, but this *IN2 bit is only ever used internally and
+   therefore defined here */
+#define CURL_CSELECT_IN2 (CURL_CSELECT_ERR << 1)
+
+int Curl_socket_check(curl_socket_t readfd, curl_socket_t readfd2,
+                      curl_socket_t writefd,
+                      long timeout_ms);
+
+/* provide the former API internally */
+#define Curl_socket_ready(x,y,z) \
+  Curl_socket_check(x, CURL_SOCKET_BAD, y, z)
+
+int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms);
+
+int Curl_wait_ms(int timeout_ms);
+
+#ifdef TPF
+int tpf_select_libcurl(int maxfds, fd_set* reads, fd_set* writes,
+                       fd_set* excepts, struct timeval* tv);
+#endif
+
+/* Winsock and TPF sockets are not in range [0..FD_SETSIZE-1], which
+   unfortunately makes it impossible for us to easily check if they're valid
+*/
+#if defined(USE_WINSOCK) || defined(TPF)
+#define VALID_SOCK(x) 1
+#define VERIFY_SOCK(x) Curl_nop_stmt
+#else
+#define VALID_SOCK(s) (((s) >= 0) && ((s) < FD_SETSIZE))
+#define VERIFY_SOCK(x) do { \
+  if(!VALID_SOCK(x)) { \
+    SET_SOCKERRNO(EINVAL); \
+    return -1; \
+  } \
+} WHILE_FALSE
+#endif
+
+#endif /* HEADER_CURL_SELECT_H */
+