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Annotation of OpenXM/doc/issac2000/ox-messages.tex, Revision 1.5

1.5     ! noro        1: %%$OpenXM: OpenXM/doc/issac2000/ox-messages.tex,v 1.4 2000/01/13 10:57:10 ohara Exp $
1.1       takayama    2:
1.4       ohara       3: \section{OX messages}
1.1       takayama    4:
                      5: An OX message for TCP/IP is a byte stream consisting of
                      6: a header and a body.
                      7: \begin{center}
                      8: \begin{tabular}{|c|c|}
                      9: \hline
                     10: Header & \hspace{10mm} Body \hspace{10mm} \\
                     11: \hline
                     12: \end{tabular}
                     13: \end{center}
                     14: The header consists of two signed 32 bit integers.
                     15: The first one is an OX tag
                     16: and the second one is a serial number of the OX message.
                     17: Negative numbers are expressed by the two's complement.
                     18: Several byte orders including the network byte order
                     19: are allowed and the byte order is determined as a part of
1.5     ! noro       20: the establishment of a connection. See Section \ref{secsession} for details.
1.1       takayama   21:
1.4       ohara      22: The OX messages are classified into three types:
1.5     ! noro       23: DATA, COMMAND, and SPECIAL.
1.1       takayama   24: We have the following main tags for the OX messages.
                     25: \begin{verbatim}
                     26: #define        OX_COMMAND               513  // COMMAND
                     27: #define        OX_DATA                  514  // DATA
1.5     ! noro       28: #define OX_SYNC_BALL             515  // SPECIAL
1.1       takayama   29: #define OX_DATA_WITH_LENGTH      521  // DATA
                     30: #define OX_DATA_OPENMATH_XML     523  // DATA
                     31: #define OX_DATA_OPENMATH_BINARY  524  // DATA
                     32: #define OX_DATA_MP               525  // DATA
                     33: \end{verbatim}
                     34:
                     35: New OX tags may be added.
                     36: The new tag should be classified into DATA or COMMAND.
1.2       takayama   37: For example, \verb+ OX_DATA_ASIR_LOCAL_BINARY +  was added a few month ago
                     38: to send internal serialized objects of asir via the OpenXM protocol.
1.4       ohara      39: This is a tag classified to DATA.
                     40: See the web page of OpenXM to add a new tag.
1.5     ! noro       41: The server is a stack machine (see Section~\ref{sec:ox-stackmachines}
        !            42: for detail).
        !            43: {\it OX data} message sent by the client
        !            44: are pushed onto the stack of the server.
        !            45: If the server gets an {\it OX command} message, then the server extracts
        !            46: a stack machine code in the OX command message and interprets the code.
1.4       ohara      47: For example, in case of SM\_executeFunction, some data are popped from
                     48: the stack and they are used as arguments of a function call.
                     49:
                     50: We explain an implementation of handling OX messages.
                     51: For example, the asir command {\tt ox\_push\_cmo(P,1)}
1.5     ! noro       52: (push integer $1$ onto the server $P$)
1.1       takayama   53: sends an OX data message
1.4       ohara      54: {\tt (OX\_DATA,(CMO\_ZZ,1))} to the server $P$.
1.1       takayama   55: Here,
                     56: OX\_DATA stands for OX\_DATA header and
1.4       ohara      57: {\tt (CMO\_ZZ,1)} is a body standing for $1$ expressed
1.2       takayama   58: in the CMO data encoding format.
1.4       ohara      59: The server tranlates $(CMO\_ZZ, 1)$ to its own internal object fotrmat
1.5     ! noro       60: for integers and pushs the object onto the stack.
1.1       takayama   61:
1.5     ! noro       62: %An OpenXM client admit that its own command sends some OX messages
        !            63: %sequentially at once.
        !            64: %
        !            65: %For example, the asir command
        !            66: %{\tt ox\_execute\_string(P, "Print[x+y]")} sends an OX data message
        !            67: %{\tt (OX\_DATA, (CMO\_STRING, "Print[x+y]"))} and an OX command message
        !            68: %{\tt (OX\_COMMAND, (SM\_executeStringByLocalParser))} to an OpenXM
        !            69: %server.