=================================================================== RCS file: /home/cvs/OpenXM/doc/issac2000/openxm-stackmachines.tex,v retrieving revision 1.1 retrieving revision 1.2 diff -u -p -r1.1 -r1.2 --- OpenXM/doc/issac2000/openxm-stackmachines.tex 1999/12/23 10:25:09 1.1 +++ OpenXM/doc/issac2000/openxm-stackmachines.tex 2000/01/02 07:32:12 1.2 @@ -1 +1,79 @@ -% $OpenXM$ +% $OpenXM: OpenXM/doc/issac2000/openxm-stackmachines.tex,v 1.1 1999/12/23 10:25:09 takayama Exp $ + +\section{OpenXM Stackmachines} (Tamura) + +In OpenXM specification, all servers are stackmachines. +These are called OpenXM stachmachines. +When a server ox\_xyz gets a OX data message, +it translates the data into its own object and push the object +on the stack. +The translation scheme together with mathematical operation definitions +of the system ox\_xyz is called the {\it phrase dictionary} of +ox\_xyz following the idea of OpenMath. + +OX command message starts with the int32 tag OX\_COMMAND. +The body is OpenXM stackmachine operation code expressed by int32. +The codes are listed below. +\begin{verbatim} +#define SM_popSerializedLocalObject 258 +#define SM_popCMO 262 +#define SM_popString 263 +#define SM_mathcap 264 +#define SM_pops 265 +#define SM_setName 266 +#define SM_evalName 267 +#define SM_executeStringByLocalParser 268 +#define SM_executeFunction 269 +#define SM_beginBlock 270 +#define SM_endBlock 271 +#define SM_shutdown 272 +#define SM_setMathCap 273 +#define SM_executeStringByLocalParserInBatchMode 274 +#define SM_getsp 275 +#define SM_dupErrors 276 +#define SM_DUMMY_sendcmo 280 +#define SM_sync_ball 281 +#define SM_control_kill 1024 +#define SM_control_to_debug_mode 1025 +#define SM_control_exit_debug_mode 1026 +#define SM_control_reset_connection 1030 +\end{verbatim} + +OpenXM does not have a standard for mathematical operation sets +while it is one of the main future projects of \cite{gap}. +Each OpenXM server has its own mathematical operation set. +Mathematical operator name, such as fctr (asir factorization command), +is pushed as a string, +SM\_executeFunction pops the operator name, the number of arguments +and arguments, +evaluates the operator, and pushes the result on the stack. +For example, the following code factorizes $x^{100}-1$ by calling +ox\_asir. +\begin{verbatim} +P = ox_launch(); +ox_push_cmo(P,x^100-1); ox_push_cmo(P,ox_int32(1)); +ox_push_cmd(P,269); +Ans = ox_pop_cmo(P); +\end{verbatim} + +When an error has occurred on an OpenXM server, +an error object is pushed to the stack instead of a result of the computation. +The error object consists of the serial number of the OX message +which caused the error, and an error message. +\begin{verbatim} +[341] ox_rpc(0,"fctr",1.2*x)$ +[342] ox_pop_cmo(0); +error([8,fctr : invalid argument]) +\end{verbatim} + +Errors are not sent to the client except a SM\_pop* command is received. +Open XM stackmachines works in the asynchoronous mode which is similar +to X servers. +For servers of graphic applications, it is an advantageous feature. +It is also easy to emulate RPC and a web server for MCP \cite{iamc} +on our OpenXM stackmachines. + + + + +