pltcl.c

关系型数据库 Postgresql 6.5.2

pltcl_quote(ClientData cdata, Tcl_Interp *interp,
			int argc, char *argv[])
{
	char	   *tmp;
	char	   *cp1;
	char	   *cp2;

	/************************************************************
	 * Check call syntax
	 ************************************************************/
	if (argc != 2)
	{
		Tcl_SetResult(interp, "syntax error - 'quote string'", TCL_VOLATILE);
		return TCL_ERROR;
	}

	/************************************************************
	 * Allocate space for the maximum the string can
	 * grow to and initialize pointers
	 ************************************************************/
	tmp = palloc(strlen(argv[1]) * 2 + 1);
	cp1 = argv[1];
	cp2 = tmp;

	/************************************************************
	 * Walk through string and double every quote and backslash
	 ************************************************************/
	while (*cp1)
	{
		if (*cp1 == '\'')
			*cp2++ = '\'';
		else
		{
			if (*cp1 == '\\')
				*cp2++ = '\\';
		}
		*cp2++ = *cp1++;
	}

	/************************************************************
	 * Terminate the string and set it as result
	 ************************************************************/
	*cp2 = '\0';
	Tcl_SetResult(interp, tmp, TCL_VOLATILE);
	pfree(tmp);
	return TCL_OK;
}


/**********************************************************************
 * pltcl_SPI_exec()		- The builtin SPI_exec command
 *				  for the safe interpreter
 **********************************************************************/
static int
pltcl_SPI_exec(ClientData cdata, Tcl_Interp *interp,
			   int argc, char *argv[])
{
	int			spi_rc;
	char		buf[64];
	int			count = 0;
	char	   *arrayname = NULL;
	int			query_idx;
	int			i;
	int			loop_rc;
	int			ntuples;
	HeapTuple  *tuples;
	TupleDesc	tupdesc = NULL;
	sigjmp_buf	save_restart;

	char	   *usage = "syntax error - 'SPI_exec "
	"?-count n? "
	"?-array name? query ?loop body?";

	/************************************************************
	 * Don't do anything if we are already in restart mode
	 ************************************************************/
	if (pltcl_restart_in_progress)
		return TCL_ERROR;

	/************************************************************
	 * Check the call syntax and get the count option
	 ************************************************************/
	if (argc < 2)
	{
		Tcl_SetResult(interp, usage, TCL_VOLATILE);
		return TCL_ERROR;
	}

	i = 1;
	while (i < argc)
	{
		if (strcmp(argv[i], "-array") == 0)
		{
			if (++i >= argc)
			{
				Tcl_SetResult(interp, usage, TCL_VOLATILE);
				return TCL_ERROR;
			}
			arrayname = argv[i++];
			continue;
		}

		if (strcmp(argv[i], "-count") == 0)
		{
			if (++i >= argc)
			{
				Tcl_SetResult(interp, usage, TCL_VOLATILE);
				return TCL_ERROR;
			}
			if (Tcl_GetInt(interp, argv[i++], &count) != TCL_OK)
				return TCL_ERROR;
			continue;
		}

		break;
	}

	query_idx = i;
	if (query_idx >= argc)
	{
		Tcl_SetResult(interp, usage, TCL_VOLATILE);
		return TCL_ERROR;
	}

	/************************************************************
	 * Prepare to start a controlled return through all
	 * interpreter levels on transaction abort
	 ************************************************************/
	memcpy(&save_restart, &Warn_restart, sizeof(save_restart));
	if (sigsetjmp(Warn_restart, 1) != 0)
	{
		memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));
		pltcl_restart_in_progress = 1;
		Tcl_SetResult(interp, "Transaction abort", TCL_VOLATILE);
		return TCL_ERROR;
	}

	/************************************************************
	 * Execute the query and handle return codes
	 ************************************************************/
	spi_rc = SPI_exec(argv[query_idx], count);
	memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));

	switch (spi_rc)
	{
		case SPI_OK_UTILITY:
			Tcl_SetResult(interp, "0", TCL_VOLATILE);
			return TCL_OK;

		case SPI_OK_SELINTO:
		case SPI_OK_INSERT:
		case SPI_OK_DELETE:
		case SPI_OK_UPDATE:
			sprintf(buf, "%d", SPI_processed);
			Tcl_SetResult(interp, buf, TCL_VOLATILE);
			return TCL_OK;

		case SPI_OK_SELECT:
			break;

		case SPI_ERROR_ARGUMENT:
			Tcl_SetResult(interp,
						  "pltcl: SPI_exec() failed - SPI_ERROR_ARGUMENT",
						  TCL_VOLATILE);
			return TCL_ERROR;

		case SPI_ERROR_UNCONNECTED:
			Tcl_SetResult(interp,
					  "pltcl: SPI_exec() failed - SPI_ERROR_UNCONNECTED",
						  TCL_VOLATILE);
			return TCL_ERROR;

		case SPI_ERROR_COPY:
			Tcl_SetResult(interp,
						  "pltcl: SPI_exec() failed - SPI_ERROR_COPY",
						  TCL_VOLATILE);
			return TCL_ERROR;

		case SPI_ERROR_CURSOR:
			Tcl_SetResult(interp,
						  "pltcl: SPI_exec() failed - SPI_ERROR_CURSOR",
						  TCL_VOLATILE);
			return TCL_ERROR;

		case SPI_ERROR_TRANSACTION:
			Tcl_SetResult(interp,
					  "pltcl: SPI_exec() failed - SPI_ERROR_TRANSACTION",
						  TCL_VOLATILE);
			return TCL_ERROR;

		case SPI_ERROR_OPUNKNOWN:
			Tcl_SetResult(interp,
						"pltcl: SPI_exec() failed - SPI_ERROR_OPUNKNOWN",
						  TCL_VOLATILE);
			return TCL_ERROR;

		default:
			sprintf(buf, "%d", spi_rc);
			Tcl_AppendResult(interp, "pltcl: SPI_exec() failed - ",
							 "unknown RC ", buf, NULL);
			return TCL_ERROR;
	}

	/************************************************************
	 * Only SELECT queries fall through to here - remember the
	 * tuples we got
	 ************************************************************/

	ntuples = SPI_processed;
	if (ntuples > 0)
	{
		tuples = SPI_tuptable->vals;
		tupdesc = SPI_tuptable->tupdesc;
	}

	/************************************************************
	 * Again prepare for elog(ERROR)
	 ************************************************************/
	if (sigsetjmp(Warn_restart, 1) != 0)
	{
		memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));
		pltcl_restart_in_progress = 1;
		Tcl_SetResult(interp, "Transaction abort", TCL_VOLATILE);
		return TCL_ERROR;
	}

	/************************************************************
	 * If there is no loop body given, just set the variables
	 * from the first tuple (if any) and return the number of
	 * tuples selected
	 ************************************************************/
	if (argc == query_idx + 1)
	{
		if (ntuples > 0)
			pltcl_set_tuple_values(interp, arrayname, 0, tuples[0], tupdesc);
		sprintf(buf, "%d", ntuples);
		Tcl_SetResult(interp, buf, TCL_VOLATILE);
		memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));
		return TCL_OK;
	}

	/************************************************************
	 * There is a loop body - process all tuples and evaluate
	 * the body on each
	 ************************************************************/
	query_idx++;
	for (i = 0; i < ntuples; i++)
	{
		pltcl_set_tuple_values(interp, arrayname, i, tuples[i], tupdesc);

		loop_rc = Tcl_Eval(interp, argv[query_idx]);

		if (loop_rc == TCL_OK)
			continue;
		if (loop_rc == TCL_CONTINUE)
			continue;
		if (loop_rc == TCL_RETURN)
		{
			memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));
			return TCL_RETURN;
		}
		if (loop_rc == TCL_BREAK)
			break;
		memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));
		return TCL_ERROR;
	}

	/************************************************************
	 * Finally return the number of tuples
	 ************************************************************/
	memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));
	sprintf(buf, "%d", ntuples);
	Tcl_SetResult(interp, buf, TCL_VOLATILE);
	return TCL_OK;
}


/**********************************************************************
 * pltcl_SPI_prepare()		- Builtin support for prepared plans
 *				  The Tcl command SPI_prepare
 *				  allways saves the plan using
 *				  SPI_saveplan and returns a key for
 *				  access. There is no chance to prepare
 *				  and not save the plan currently.
 **********************************************************************/
static int
pltcl_SPI_prepare(ClientData cdata, Tcl_Interp *interp,
				  int argc, char *argv[])
{
	int			nargs;
	char	  **args;
	pltcl_query_desc *qdesc;
	void	   *plan;
	int			i;
	HeapTuple	typeTup;
	Tcl_HashEntry *hashent;
	int			hashnew;
	sigjmp_buf	save_restart;

	/************************************************************
	 * Don't do anything if we are already in restart mode
	 ************************************************************/
	if (pltcl_restart_in_progress)
		return TCL_ERROR;

	/************************************************************
	 * Check the call syntax
	 ************************************************************/
	if (argc != 3)
	{
		Tcl_SetResult(interp, "syntax error - 'SPI_prepare query argtypes'",
					  TCL_VOLATILE);
		return TCL_ERROR;
	}

	/************************************************************
	 * Split the argument type list
	 ************************************************************/
	if (Tcl_SplitList(interp, argv[2], &nargs, &args) != TCL_OK)
		return TCL_ERROR;

	/************************************************************
	 * Allocate the new querydesc structure
	 ************************************************************/
	qdesc = (pltcl_query_desc *) malloc(sizeof(pltcl_query_desc));
	sprintf(qdesc->qname, "%lx", (long) qdesc);
	qdesc->nargs = nargs;
	qdesc->argtypes = (Oid *) malloc(nargs * sizeof(Oid));
	qdesc->arginfuncs = (FmgrInfo *) malloc(nargs * sizeof(FmgrInfo));
	qdesc->argtypelems = (Oid *) malloc(nargs * sizeof(Oid));
	qdesc->argvalues = (Datum *) malloc(nargs * sizeof(Datum));
	qdesc->arglen = (int *) malloc(nargs * sizeof(int));

	/************************************************************
	 * Prepare to start a controlled return through all
	 * interpreter levels on transaction abort
	 ************************************************************/
	memcpy(&save_restart, &Warn_restart, sizeof(save_restart));
	if (sigsetjmp(Warn_restart, 1) != 0)
	{
		memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));
		pltcl_restart_in_progress = 1;
		free(qdesc->argtypes);
		free(qdesc->arginfuncs);
		free(qdesc->argtypelems);
		free(qdesc->argvalues);
		free(qdesc->arglen);
		free(qdesc);
		ckfree(args);
		return TCL_ERROR;
	}

	/************************************************************
	 * Lookup the argument types by name in the system cache
	 * and remember the required information for input conversion
	 ************************************************************/
	for (i = 0; i < nargs; i++)
	{
		typeTup = SearchSysCacheTuple(TYPNAME,
									  PointerGetDatum(args[i]),
									  0, 0, 0);
		if (!HeapTupleIsValid(typeTup))
			elog(ERROR, "pltcl: Cache lookup of type %s failed", args[i]);
		qdesc->argtypes[i] = typeTup->t_data->t_oid;
		fmgr_info(((Form_pg_type) GETSTRUCT(typeTup))->typinput,
				  &(qdesc->arginfuncs[i]));
		qdesc->argtypelems[i] = ((Form_pg_type) GETSTRUCT(typeTup))->typelem;
		qdesc->argvalues[i] = (Datum) NULL;
		qdesc->arglen[i] = (int) (((Form_pg_type) GETSTRUCT(typeTup))->typlen);
	}

	/************************************************************
	 * Prepare the plan and check for errors
	 ************************************************************/
	plan = SPI_prepare(argv[1], nargs, qdesc->argtypes);

	if (plan == NULL)
	{
		char		buf[128];
		char	   *reason;

		memcpy(&Warn_restart, &save_restart, sizeof(Warn_restart));

		switch (SPI_result)
		{
			case SPI_ERROR_ARGUMENT:
				reason = "SPI_ERROR_ARGUMENT";
				break;

			case SPI_ERROR_UNCONNECTED:
				reason = "SPI_ERROR_UNCONNECTED";
				break;

			case SPI_ERROR_COPY:
				reason = "SPI_ERROR_COPY";
				break;

			case SPI_ERROR_CURSOR:
				reason = "SPI_ERROR_CURSOR";
				break;

			case SPI_ERROR_TRANSACTION:
				reason = "SPI_ERROR_TRANSACTION";
				break;

			case SPI_ERROR_OPUNKNOWN:
				reason = "SPI_ERROR_OPUNKNOWN";
				break;

			default:
				sprintf(buf, "unknown RC %d", SPI_result);
				reason = buf;