Select polling mechanisms at one place

This patch provides a single place for selecting polling mechanisms
(polling.hpp). Up to now the selection was spread among the build
system and several source files.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

17 files changed, 110 insertions, 75 deletions

diff --git a/builds/msvc/libxs/libxs.vcxproj b/builds/msvc/libxs/libxs.vcxproj
index d4f40ca..229d7ec 100644
--- a/builds/msvc/libxs/libxs.vcxproj
+++ b/builds/msvc/libxs/libxs.vcxproj
@@ -206,6 +206,7 @@
     <ClInclude Include="..\..\..\src\pgm_socket.hpp" />
     <ClInclude Include="..\..\..\src\pipe.hpp" />
     <ClInclude Include="..\..\..\src\poll.hpp" />
+    <ClInclude Include="..\..\..\src\polling.hpp" />
     <ClInclude Include="..\..\..\src\precompiled.hpp" />
     <ClInclude Include="..\..\..\src\prefix_filter.hpp" />
     <ClInclude Include="..\..\..\src\pub.hpp" />
@@ -244,4 +245,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/builds/msvc/libxs/libxs.vcxproj.filters b/builds/msvc/libxs/libxs.vcxproj.filters
index 1fefb60..a1b80e3 100644
--- a/builds/msvc/libxs/libxs.vcxproj.filters
+++ b/builds/msvc/libxs/libxs.vcxproj.filters
@@ -301,6 +301,9 @@
     <ClInclude Include="..\..\..\src\poll.hpp">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\..\src\polling.hpp">
+      <Filter>Header Files</Filter>
+    </ClInclude>
     <ClInclude Include="..\..\..\src\precompiled.hpp">
       <Filter>Header Files</Filter>
     </ClInclude>
@@ -413,4 +416,4 @@
       <Filter>Header Files</Filter>
     </ClInclude>
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/Makefile.am b/src/Makefile.am
index 3025e13..03b6381 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -55,6 +55,7 @@ libxs_la_SOURCES = \
     pipe.hpp \
     platform.hpp \
     poll.hpp \
+    polling.hpp \
     pair.hpp \
     prefix_filter.hpp \
     pub.hpp \
diff --git a/src/devpoll.cpp b/src/devpoll.cpp
index 76943f0..2fbd1c1 100644
--- a/src/devpoll.cpp
+++ b/src/devpoll.cpp
@@ -21,7 +21,7 @@
 
 #include "devpoll.hpp"
 
-#if defined XS_HAVE_DEVPOLL
+#if defined XS_USE_ASYNC_DEVPOLL
 
 #include <sys/devpoll.h>
 #include <sys/time.h>
@@ -33,6 +33,7 @@
 #include <limits.h>
 #include <algorithm>
 
+#include "platform.hpp"
 #include "devpoll.hpp"
 #include "err.hpp"
 #include "config.hpp"
diff --git a/src/devpoll.hpp b/src/devpoll.hpp
index 3e35a99..975b442 100644
--- a/src/devpoll.hpp
+++ b/src/devpoll.hpp
@@ -22,9 +22,9 @@
 #ifndef __XS_DEVPOLL_HPP_INCLUDED__
 #define __XS_DEVPOLL_HPP_INCLUDED__
 
-#include "platform.hpp"
+#include "polling.hpp"
 
-#if defined XS_HAVE_DEVPOLL
+#if defined XS_USE_ASYNC_DEVPOLL
 
 #include <vector>
 
diff --git a/src/epoll.cpp b/src/epoll.cpp
index 8ba2f17..ecdee1a 100644
--- a/src/epoll.cpp
+++ b/src/epoll.cpp
@@ -21,7 +21,7 @@
 
 #include "epoll.hpp"
 
-#if defined XS_HAVE_EPOLL
+#if defined XS_USE_ASYNC_EPOLL
 
 #include <sys/epoll.h>
 #include <stdlib.h>
diff --git a/src/epoll.hpp b/src/epoll.hpp
index 595168e..6d2f8be 100644
--- a/src/epoll.hpp
+++ b/src/epoll.hpp
@@ -22,9 +22,9 @@
 #ifndef __XS_EPOLL_HPP_INCLUDED__
 #define __XS_EPOLL_HPP_INCLUDED__
 
-#include "platform.hpp"
+#include "polling.hpp"
 
-#if defined XS_HAVE_EPOLL
+#if defined XS_USE_ASYNC_EPOLL
 
 #include <vector>
 #include <sys/epoll.h>
diff --git a/src/io_thread.cpp b/src/io_thread.cpp
index df5a623..c363592 100644
--- a/src/io_thread.cpp
+++ b/src/io_thread.cpp
@@ -21,6 +21,7 @@
 #include "io_thread.hpp"
 #include "err.hpp"
 
+#include "polling.hpp"
 #include "select.hpp"
 #include "poll.hpp"
 #include "epoll.hpp"
@@ -30,15 +31,15 @@
 xs::io_thread_t *xs::io_thread_t::create (xs::ctx_t *ctx_, uint32_t tid_)
 {
     io_thread_t *result;
-#if defined XS_HAVE_SELECT
+#if defined XS_USE_ASYNC_SELECT
     result = new (std::nothrow) select_t (ctx_, tid_);
-#elif defined XS_HAVE_POLL
+#elif defined XS_USE_ASYNC_POLL
     result = new (std::nothrow) poll_t (ctx_, tid_);
-#elif defined XS_HAVE_EPOLL
+#elif defined XS_USE_ASYNC_EPOLL
     result = new (std::nothrow) epoll_t (ctx_, tid_);
-#elif defined XS_HAVE_DEVPOLL
+#elif defined XS_USE_ASYNC_DEVPOLL
     result = new (std::nothrow) devpoll_t (ctx_, tid_);
-#elif defined XS_HAVE_KQUEUE
+#elif defined XS_USE_ASYNC_KQUEUE
     result = new (std::nothrow) kqueue_t (ctx_, tid_);
 #endif
     alloc_assert (result);
diff --git a/src/kqueue.cpp b/src/kqueue.cpp
index c3ef5b5..06e22d3 100644
--- a/src/kqueue.cpp
+++ b/src/kqueue.cpp
@@ -21,7 +21,7 @@
 
 #include "kqueue.hpp"
 
-#if defined XS_HAVE_KQUEUE
+#if defined XS_USE_ASYNC_KQUEUE
 
 #include <sys/time.h>
 #include <sys/types.h>
@@ -31,6 +31,7 @@
 #include <algorithm>
 #include <new>
 
+#include "platform.hpp"
 #include "kqueue.hpp"
 #include "err.hpp"
 #include "config.hpp"
diff --git a/src/kqueue.hpp b/src/kqueue.hpp
index 3aaa10b..862458b 100644
--- a/src/kqueue.hpp
+++ b/src/kqueue.hpp
@@ -22,8 +22,9 @@
 #ifndef __XS_KQUEUE_HPP_INCLUDED__
 #define __XS_KQUEUE_HPP_INCLUDED__
 
-#include "platform.hpp"
-#if defined XS_HAVE_KQUEUE
+#include "polling.hpp"
+
+#if defined XS_USE_ASYNC_KQUEUE
 
 #include <vector>
 
diff --git a/src/poll.cpp b/src/poll.cpp
index c0f070e..9f901fc 100644
--- a/src/poll.cpp
+++ b/src/poll.cpp
@@ -21,7 +21,7 @@
 
 #include "poll.hpp"
 
-#if defined XS_HAVE_POLL
+#if defined XS_USE_ASYNC_POLL
 
 #include <sys/types.h>
 #include <sys/time.h>
diff --git a/src/poll.hpp b/src/poll.hpp
index 2df1796..c192a77 100644
--- a/src/poll.hpp
+++ b/src/poll.hpp
@@ -22,9 +22,9 @@
 #ifndef __XS_POLL_HPP_INCLUDED__
 #define __XS_POLL_HPP_INCLUDED__
 
-#include "platform.hpp"
+#include "polling.hpp"
 
-#if defined XS_HAVE_POLL
+#if defined XS_USE_ASYNC_POLL
 
 #include <poll.h>
 #include <stddef.h>
diff --git a/src/polling.hpp b/src/polling.hpp
new file mode 100644
index 0000000..b8f0540
--- /dev/null
+++ b/src/polling.hpp
@@ -0,0 +1,68 @@
+/*
+    Copyright (c) 2012 250bpm s.r.o.
+    Copyright (c) 2012 Other contributors as noted in the AUTHORS file
+
+    This file is part of Crossroads I/O project.
+
+    Crossroads I/O is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    Crossroads is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __XS_CORE_HPP_INCLUDED__
+#define __XS_CORE_HPP_INCLUDED__
+
+#include "platform.hpp"
+
+//  This header file contains code that decides what polling mechanisms
+//  should be used in individual cases. It also includes appropriate headers.
+//
+//  ASYNC polling mechanism to drive event loops in the I/O threads.
+//  SYNC polling mechanism is used in xs_poll() and for blocking API functions.
+
+#if defined XS_FORCE_SELECT
+#define XS_USE_ASYNC_SELECT
+#elif defined XS_FORCE_POLL
+#define XS_USE_ASYNC_POLL
+#elif defined XS_FORCE_EPOLL
+#define XS_USE_ASYNC_EPOLL
+#elif defined XS_FORCE_DEVPOLL
+#define XS_USE_ASYNC_DEVPOLL
+#elif defined XS_FORCE_KQUEUE
+#define XS_USE_ASYNC_KQUEUE
+#elif defined XS_HAVE_EPOLL
+#define XS_USE_ASYNC_EPOLL
+#elif defined XS_HAVE_DEVPOLL
+#define XS_USE_ASYNC_DEVPOLL
+#elif defined XS_HAVE_KQUEUE
+#define XS_USE_ASYNC_KQUEUE
+#elif defined XS_HAVE_POLL
+#define XS_USE_ASYNC_POLL
+#elif defined XS_HAVE_SELECT
+#define XS_USE_ASYNC_SELECT
+#else
+#error No polling mechanism available!
+#endif
+
+#if defined XS_FORCE_SELECT
+#define XS_USE_SYNC_SELECT
+#elif defined XS_FORCE_POLL
+#define XS_USE_SYNC_POLL
+#elif defined XS_HAVE_POLL
+#define XS_USE_SYNC_POLL
+#elif defined XS_HAVE_SELECT
+#define XS_USE_SYNC_SELECT
+#else
+#error No polling mechanism available!
+#endif
+
+#endif
diff --git a/src/select.cpp b/src/select.cpp
index eeac5a9..72346a4 100644
--- a/src/select.cpp
+++ b/src/select.cpp
@@ -21,7 +21,7 @@
 
 #include "select.hpp"
 
-#if defined XS_HAVE_SELECT
+#if defined XS_USE_ASYNC_SELECT
 
 #include "platform.hpp"
 #if defined XS_HAVE_WINDOWS
diff --git a/src/select.hpp b/src/select.hpp
index ea2831d..df188eb 100644
--- a/src/select.hpp
+++ b/src/select.hpp
@@ -22,9 +22,9 @@
 #ifndef __XS_SELECT_HPP_INCLUDED__
 #define __XS_SELECT_HPP_INCLUDED__
 
-#include "platform.hpp"
+#include "polling.hpp"
 
-#if defined XS_HAVE_SELECT
+#if defined XS_USE_ASYNC_SELECT
 
 #include "platform.hpp"
 
diff --git a/src/signaler.cpp b/src/signaler.cpp
index 8832c6b..1f754f6 100644
--- a/src/signaler.cpp
+++ b/src/signaler.cpp
@@ -19,29 +19,15 @@
 */
 
 #include "platform.hpp"
-
-#if defined XS_HAVE_SELECT
-#define XS_SIGNALER_WAIT_BASED_ON_SELECT
-#elif defined XS_HAVE_POLL
-#define XS_SIGNALER_WAIT_BASED_ON_POLL
-#elif defined XS_HAVE_LINUX || defined XS_HAVE_FREEBSD ||\
-    defined XS_HAVE_OPENBSD || defined XS_HAVE_SOLARIS ||\
-    defined XS_HAVE_OSX || defined XS_HAVE_QNXNTO ||\
-    defined XS_HAVE_HPUX || defined XS_HAVE_AIX ||\
-    defined XS_HAVE_NETBSD
-#define XS_SIGNALER_WAIT_BASED_ON_POLL
-#elif defined XS_HAVE_WINDOWS || defined XS_HAVE_OPENVMS ||\
-	defined XS_HAVE_CYGWIN
-#define XS_SIGNALER_WAIT_BASED_ON_SELECT
-#endif
+#include "polling.hpp"
 
 //  On AIX, poll.h has to be included before xs.h to get consistent
 //  definition of pollfd structure (AIX uses 'reqevents' and 'retnevents'
 //  instead of 'events' and 'revents' and defines macros to map from POSIX-y
 //  names to AIX-specific names).
-#if defined XS_SIGNALER_WAIT_BASED_ON_POLL
+#if defined XS_USE_SYNC_POLL
 #include <poll.h>
-#elif defined XS_SIGNALER_WAIT_BASED_ON_SELECT
+#elif defined XS_USE_SYNC_SELECT
 #if defined XS_HAVE_WINDOWS
 #include "windows.hpp"
 #elif defined XS_HAVE_HPUX
@@ -357,7 +343,7 @@ void xs::signaler_send (xs::signaler_t *self_)
 
 int xs::signaler_wait (xs::signaler_t *self_, int timeout_)
 {
-#ifdef XS_SIGNALER_WAIT_BASED_ON_POLL
+#ifdef XS_USE_SYNC_POLL
 
     struct pollfd pfd;
     pfd.fd = self_->r;
@@ -375,7 +361,7 @@ int xs::signaler_wait (xs::signaler_t *self_, int timeout_)
     xs_assert (pfd.revents & POLLIN);
     return 0;
 
-#elif defined XS_SIGNALER_WAIT_BASED_ON_SELECT
+#elif defined XS_USE_SYNC_SELECT
 
     fd_set fds;
     FD_ZERO (&fds);
@@ -406,6 +392,7 @@ int xs::signaler_wait (xs::signaler_t *self_, int timeout_)
 
 #else
 #error
+    return -1;
 #endif
 }
 
@@ -441,10 +428,3 @@ void xs::signaler_recv (xs::signaler_t *self_)
 #endif
 }
 
-#if defined XS_SIGNALER_WAIT_BASED_ON_SELECT
-#undef XS_SIGNALER_WAIT_BASED_ON_SELECT
-#endif
-#if defined XS_SIGNALER_WAIT_BASED_ON_POLL
-#undef XS_SIGNALER_WAIT_BASED_ON_POLL
-#endif
-
diff --git a/src/upoll.cpp b/src/upoll.cpp
index d99deec..089a6a5 100644
--- a/src/upoll.cpp
+++ b/src/upoll.cpp
@@ -26,27 +26,13 @@
 #include "clock.hpp"
 #include "likely.hpp"
 #include "platform.hpp"
-
-#if defined XS_HAVE_SELECT
-#define XS_POLL_BASED_ON_SELECT
-#elif defined XS_HAVE_POLL
-#define XS_POLL_BASED_ON_POLL
-#elif defined XS_HAVE_LINUX || defined XS_HAVE_FREEBSD ||\
-    defined XS_HAVE_OPENBSD || defined XS_HAVE_SOLARIS ||\
-    defined XS_HAVE_OSX || defined XS_HAVE_QNXNTO ||\
-    defined XS_HAVE_HPUX || defined XS_HAVE_AIX ||\
-    defined XS_HAVE_NETBSD
-#define XS_POLL_BASED_ON_POLL
-#elif defined XS_HAVE_WINDOWS || defined XS_HAVE_OPENVMS ||\
-	defined XS_HAVE_CYGWIN
-#define XS_POLL_BASED_ON_SELECT
-#endif
+#include "polling.hpp"
 
 //  On AIX platform, poll.h has to be included first to get consistent
 //  definition of pollfd structure (AIX uses 'reqevents' and 'retnevents'
 //  instead of 'events' and 'revents' and defines macros to map from POSIX-y
 //  names to AIX-specific names).
-#if defined XS_POLL_BASED_ON_POLL
+#if defined XS_USE_SYNC_POLL
 #include <poll.h>
 #endif
 
@@ -58,7 +44,7 @@
 
 int xs::upoll (xs_pollitem_t *items_, int nitems_, int timeout_)
 {
-#if defined XS_POLL_BASED_ON_POLL
+#if defined XS_USE_SYNC_POLL
     if (unlikely (nitems_ < 0)) {
         errno = EINVAL;
         return -1;
@@ -213,7 +199,7 @@ int xs::upoll (xs_pollitem_t *items_, int nitems_, int timeout_)
     free (pollfds);
     return nevents;
 
-#elif defined XS_POLL_BASED_ON_SELECT
+#elif defined XS_USE_SYNC_SELECT
 
     if (unlikely (nitems_ < 0)) {
         errno = EINVAL;
@@ -403,15 +389,7 @@ int xs::upoll (xs_pollitem_t *items_, int nitems_, int timeout_)
     return nevents;
 
 #else
-    //  Exotic platforms that support neither poll() nor select().
-    errno = ENOTSUP;
-    return -1;
+#error
 #endif
 }
 
-#if defined XS_POLL_BASED_ON_SELECT
-#undef XS_POLL_BASED_ON_SELECT
-#endif
-#if defined XS_POLL_BASED_ON_POLL
-#undef XS_POLL_BASED_ON_POLL
-#endif