Fix Cygwin 1.7 build.

Avoid using Cygwin sockets as our code assumes that we use WinSock API under
Windows currently (this might change in the future) by defining
__USE_W32_SOCKETS.

Use new, safer and more efficient cygwin_conv_path() function.

Use t_str() instead of fn_str() with Windows API taking file names, under
Cygwin they are different and using fn_str() is incorrect.

A few other minor fixes.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@65057 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/app.h

@@ -497,7 +497,7 @@ protected:
     wxDECLARE_NO_COPY_CLASS(wxAppConsoleBase);
 };
 
-#if defined(__UNIX__)
+#if defined(__UNIX__) && !defined(__CYGWIN__)
     #include "wx/unix/app.h"
 #else
     // this has to be a class and not a typedef as we forward declare it

include/wx/defs.h

@@ -193,6 +193,12 @@
 #define va_list __gnuc_va_list
 #endif /*  HP-UX */
 
+/* Prevents conflicts between sys/types.h and winsock.h with Cygwin, */
+/* when using Windows sockets. */
+#if defined(__CYGWIN__) && (__WXMSW__)
+#define __USE_W32_SOCKETS
+#endif
+
 /*  ---------------------------------------------------------------------------- */
 /*  check for native bool type and TRUE/FALSE constants */
 /*  ---------------------------------------------------------------------------- */

include/wx/evtloop.h

@@ -17,7 +17,7 @@
 
 // TODO: implement wxEventLoopSource for MSW (it should wrap a HANDLE and be
 //       monitored using MsgWaitForMultipleObjects())
-#if defined(__WXOSX__) || defined(__UNIX__)
+#if defined(__WXOSX__) || (defined(__UNIX__) && !defined(__CYGWIN__))
     #define wxUSE_EVENTLOOP_SOURCE 1
 #else
     #define wxUSE_EVENTLOOP_SOURCE 0
@@ -310,7 +310,7 @@ protected:
 #endif // wxUSE_GUI
 
 // include the header defining wxConsoleEventLoop for Unix systems
-#if defined(__UNIX__)
+#if defined(__UNIX__) && !defined(__CYGWIN__)
 #include "wx/unix/evtloop.h"
 #endif
 

include/wx/filefn.h

@@ -578,7 +578,8 @@ inline int wxLstat(const wxString& path, wxStructStat *buf)
     { return wxCRT_Lstat(path.fn_str(), buf); }
 inline int wxRmDir(const wxString& path)
     { return wxCRT_RmDir(path.fn_str()); }
-#if defined(__WINDOWS__) || (defined(__OS2__) && defined(__WATCOMC__))
+#if (defined(__WINDOWS__) && !defined(__CYGWIN__)) \
+        || (defined(__OS2__) && defined(__WATCOMC__))
 inline int wxMkDir(const wxString& path, mode_t WXUNUSED(mode) = 0)
     { return wxCRT_MkDir(path.fn_str()); }
 #else