Initial support for MacOS.

This will soon be complemented with MacOS specific source code files and
INSTALL.MacOS.

I (Andy) have decided to get rid of a number of #include <sys/types.h>.
I've verified it's ok (both by examining /usr/include/*.h and compiling)
on a number of Unix platforms. Unfortunately I don't have Windows box
to verify this on. I really appreciate if somebody could try to compile
it and contact me a.s.a.p. in case a problem occurs.

Submitted by: Roy Wood <roy@centricsystems.ca>
Reviewed by: Andy Polyakov <appro@fy.chalmers.se>
diff --git a/e_os.h b/e_os.h
index 5eaa3cc..61ff56e 100644
--- a/e_os.h
+++ b/e_os.h
@@ -82,6 +82,15 @@
 #define DEVRANDOM "/dev/urandom"
 #endif
 
+#if defined(__MWERKS__) && defined(macintosh)
+# if macintosh==1
+#  define MAC_OS_pre_X
+#  define NO_SYS_TYPES_H
+#  define NO_CHMOD
+#  define NO_SYSLOG
+# endif
+#endif
+
 /********************************************************************
  The Microsoft section
  ********************************************************************/
@@ -119,6 +128,12 @@
 #define readsocket(s,b,n)	recv((s),(b),(n),0)
 #define writesocket(s,b,n)	send((s),(b),(n),0)
 #define EADDRINUSE		WSAEADDRINUSE
+#elif MAC_OS_pre_X
+#define get_last_socket_error()	errno
+#define clear_socket_error()	errno=0
+#define closesocket(s)		MacSocket_close(s)
+#define readsocket(s,b,n)	MacSocket_recv((s),(b),(n),true)
+#define writesocket(s,b,n)	MacSocket_send((s),(b),(n))
 #else
 #define get_last_socket_error()	errno
 #define clear_socket_error()	errno=0
@@ -268,6 +283,13 @@
 #      define SHUTDOWN2(fd)		{ shutdown((fd),2); closesocket(fd); }
 #    endif
 
+#  elif defined(MAC_OS_pre_X)
+
+#    include "MacSocket.h"
+#    define SSLeay_Write(a,b,c)		MacSocket_send((a),(b),(c))
+#    define SSLeay_Read(a,b,c)		MacSocket_recv((a),(b),(c),true)
+#    define SHUTDOWN(fd)		MacSocket_close(fd)
+#    define SHUTDOWN2(fd)		MacSocket_close(fd)
 
 #  else