porting.doc

Porting the Simple Sockets Library Dr. Charles E. Campbell, Jr.

                       Porting the Simple Sockets Library
                          Dr. Charles E. Campbell, Jr.

1.  Most SSL porting issues are handled in the header file, "sockets.h".  The
    leading portion of the file has several machine specific sections:

        #ifdef vms
        ...
        #endif
        
        #ifdef apollo
        ...
        #endif
        
        #ifdef sgi
        ...
        #endif
    
        etc.

    These machine specific sections mostly contain #include <some tcp/ip header
    file> stuff; your new machine section must be set up to include the
    appropriate header files, too, but they'll probably have nearly the same
    set of header file names.

    Each machine section  also usually has a

       #ifdef SSLNEEDTIME
       ...
       #endif

    subsection which includes the time header file information needed by select().

2.  Some machines have case insensitive linkers, such as MS-DOS.  The usual solution
    is to put

        # define Sscanf  Sktscanf
        # define Sprintf Sktprintf
    
    in the machine-specific section.

3. There are three options for the SSL that support different machines:

        #define SSLNOSETSOCKOPT
        #define SSLNOPEEK
        #define SSLNEEDTOSHAREPM

   The SSLNOSETSOCKOPT is for those machines whose Berkeley sockets API does
   not support the setsockopt() function (or, if present, doesn't support the
   TCP_NODELAY option).

   The SSLNOPEEK is for those machines whose Berkeley sockets API does not
   support the MSG_PEEK option on a recv().

   The SSLNEEDTOSHAREPM is for those machines which lack multi-tasking; ie.
   cannot run a PortMaster in the background.  Those machines need to share
   another machine's PortMaster for any servers to be run on them.  Clients are
   unaffected.

4. There are a few MSDOS exceptions in <Sopen.c> and <Sscanf.c>.

   The <Sopen.c> ones initialize the WIN/API DOS Socket Library.  If your
   tcp/ip Berkeley sockets requires a call to some initialization function,
   this is the place to do it.

   The <Sscanf.c> MSDOS exceptions support MicroSoft C's requirement to have
   its first argument to va_start() and va_arg() be "char *" instead of "void
   *".

5. Some middle-aged C compilers allowed prototyping, but were not ANSI-C
   compliant.  In <xtdio.h>, at or near line 78, is a preprocessor block:

    #  if defined(sgi)   || defined(apollo)    || defined(__STDC__) || \
          defined(MSDOS) || defined(MCH_AMIGA) || defined(__osf__)
    #   define __PROTOTYPE__
    ...

    If your machine's compiler fits this bill, you should (this is not
    required, merely suggested) put it on the #if defined() ... list of
    machines so that the compiler would use prototyping.  Prototyping will
    likely save you some syntax errors in your future.

    One caveat: the cprt() and sprt() functions use the keyword "const".  Your
    middle-aged C compiler may, or may not, support that keyword.  If not,
    you'll be getting some syntax errors from the <xtdio.h> line near the
    prototypes for those two functions.  The solution is simple: in <xtdio.h>
    near line 94 is

    #define const

    buried inside a comment about this problem.  Move that line out of the
    comment, and the "const" problems should disappear.

6. SCO/Unix sockets:  You may need additional network products such as

   SCO Unix 3.2v4:
      - SCO Unix runtime
      - SCO Unix Development System
      - SCO TCP/IP Runtime
      - SCO TCP/IP Development System

   Open Desktop 2 or 3:  ODT Development System

   OpenServer 5: all include files and libraries are already supplied with the o/s

   Note -- I (C Campbell) have never used SCO, so I can not personally attest as to
   what your SCO variant may or may not need.