firebird-mirror/src/qli/exe.cpp

/*
 *	PROGRAM:	JRD Command Oriented Query Language
 *	MODULE:		exe.cpp
 *	DESCRIPTION:	Execution phase
 *
 * The contents of this file are subject to the Interbase Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy
 * of the License at http://www.Inprise.com/IPL.html
 *
 * Software distributed under the License is distributed on an
 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code was created by Inprise Corporation
 * and its predecessors. Portions created by Inprise Corporation are
 * Copyright (C) Inprise Corporation.
 *
 * All Rights Reserved.
 * Contributor(s): ______________________________________.
 */

#include "firebird.h"
#include <stdio.h>
#include <setjmp.h>

#include "../jrd/ibase.h"
#include "../qli/dtr.h"
#include "../qli/exe.h"
#include "../qli/all_proto.h"
#include "../qli/err_proto.h"
#include "../qli/eval_proto.h"
#include "../qli/exe_proto.h"
#include "../qli/report.h"
#include "../qli/forma_proto.h"
#include "../qli/mov_proto.h"
#include "../qli/repor_proto.h"
#include "../jrd/gds_proto.h"
#include "../jrd/utl_proto.h"
#include "../common/classes/UserBlob.h"

using MsgFormat::SafeArg;


#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef HAVE_VFORK_H
#include <vfork.h>
#endif

#ifdef HAVE_STRING_H
#include <string.h>
#endif

const char* FOPEN_WRITE_TYPE	= "w";

static DSC *assignment(qli_nod*, DSC *, qli_nod*, qli_nod*, qli_par*);
static void commit_retaining(qli_nod*);
static bool copy_blob(qli_nod*, qli_par*);
static void db_error(qli_req*, ISC_STATUS *);
static void execute_abort(qli_nod*);
static void execute_assignment(qli_nod*);
static void execute_for(qli_nod*);
static void execute_modify(qli_nod*);
static void execute_output(qli_nod*);
static void execute_print(qli_nod*);
static void execute_repeat(qli_nod*);
static void execute_store(qli_nod*);
static void map_data(qli_msg*);
static void print_counts(qli_req*);
static void set_null(qli_msg*);
static void transaction_state(qli_nod*, DBB);

// definitions for SET COUNT

const int COUNT_ITEMS	= 4;

static const SCHAR count_info[] = 
{
	isc_info_req_select_count,
	isc_info_req_insert_count,
	isc_info_req_update_count,
	isc_info_req_delete_count
};


void EXEC_abort(void)
{
/**************************************
 *
 *	E X E C _ a b o r t
 *
 **************************************
 *
 * Functional description
 *	An asynchrous abort has been requested.  Request that all
 *	requests be unwound and set flag.
 *
 **************************************/
	ISC_STATUS_ARRAY status_vector;

	for (qli_req* request = QLI_requests; request; request = request->req_next)
	{
		if (request->req_handle)
			isc_unwind_request(status_vector, &request->req_handle, 0);
	}

	QLI_abort = true;
}


void EXEC_execute( qli_nod* node)
{
/**************************************
 *
 *	E X E C _ e x e c u t e
 *
 **************************************
 *
 * Functional description
 *	Execute a node.
 *
 **************************************/
	if (QLI_abort)
		EXEC_poll_abort();

	if (node) {
		switch (node->nod_type) 
		{
		case nod_abort:
			execute_abort(node);

		case nod_assign:
			execute_assignment(node);
			return;

		case nod_commit_retaining:
			commit_retaining(node);
			return;

		case nod_erase:
			{
				qli_msg* message = (qli_msg*) node->nod_arg[e_era_message];
				if (message)
					EXEC_send(message);
			}
			return;

		case nod_for:
			execute_for(node);
			return;

		case nod_list:
			{
				qli_nod** ptr = node->nod_arg;
				for (USHORT i = 0; i < node->nod_count; i++)
					EXEC_execute(*ptr++);
			}
			return;

		case nod_modify:
			execute_modify(node);
			return;

		case nod_output:
			execute_output(node);
			return;

		case nod_print:
			execute_print(node);
			return;

		case nod_repeat:
			execute_repeat(node);
			return;

		case nod_store:
			execute_store(node);
			return;

		case nod_if:
			if (EVAL_boolean(node->nod_arg[e_if_boolean])) {
				EXEC_execute(node->nod_arg[e_if_true]);
				return;
			}
			if (node->nod_arg[e_if_false]) {
				EXEC_execute(node->nod_arg[e_if_false]);
				return;
			}
			return;

		case nod_report_loop:
			RPT_report(node);
			return;

		default:
			ERRQ_bugcheck(33);		// Msg33 EXEC_execute: not implemented
		}
	}
}


FB_API_HANDLE EXEC_open_blob( qli_nod* node)
{
/**************************************
 *
 *	E X E C _ o p e n _ b l o b
 *
 **************************************
 *
 * Functional description
 *	Given a blob field node, open and return the blob.
 *
 **************************************/
	dsc* desc = EVAL_value(node);
	if (!desc)
		return 0;

// Starting from the print item, work our way back to the database block

	if (node->nod_type == nod_reference)
		node = node->nod_arg[0];

	if (node->nod_type != nod_field)
		ERRQ_bugcheck(34);			// Msg34 print_blob: expected field node

	qli_ctx* context = (qli_ctx*) node->nod_arg[e_fld_context];
	qli_req* request = context->ctx_request;
	DBB dbb = request->req_database;
	FB_API_HANDLE blob = 0;

// Format blob parameter block
	UCHAR bpb[20];
	UCHAR* p = bpb;
	*p++ = isc_bpb_version1;
	*p++ = isc_bpb_source_type;
	*p++ = 2;
	*p++ = desc->dsc_sub_type;
	*p++ = desc->dsc_sub_type >> 8;
	*p++ = isc_bpb_target_type;
	*p++ = 1;
	*p++ = 1;

	const USHORT bpb_length = p - bpb;

	ISC_STATUS_ARRAY status_vector;
	if (isc_open_blob2(status_vector, &dbb->dbb_handle, &dbb->dbb_transaction,
						&blob, (ISC_QUAD*) desc->dsc_address, bpb_length,
						bpb))
	{
		ERRQ_database_error(dbb, status_vector);
	}

	return blob;
}


FILE* EXEC_open_output(qli_nod* node)
{
/**************************************
 *
 *	E X E C _ o p e n _ o u t p u t
 *
 **************************************
 *
 * Functional description
 *	Open output stream to re-direct output.
 *
 **************************************/
// Evaluate filename and copy to a null terminated string

	dsc* desc = EVAL_value(node->nod_arg[e_out_file]);
	const TEXT* p = NULL;
	TEXT temp[64];
	SSHORT l = MOVQ_get_string(desc, &p, (vary*) temp, sizeof(temp));
	if (l >= MAXPATHLEN)
		l = MAXPATHLEN - 1;

	TEXT filename[MAXPATHLEN];
	if (l)
		memcpy(filename, p, l);

	filename[l] = 0;

// If output is to a file, just do it

	if (!node->nod_arg[e_out_pipe]) {
	    FILE* out_file = fopen(filename, FOPEN_WRITE_TYPE);
		if (out_file)
			return out_file;

		ERRQ_print_error(42, filename);
		// Msg42 Can't open output file %s
	}

// Output is to a file.  Setup file and fork process

#ifdef WIN_NT
	FILE* out_file = _popen(filename, "w");
	if (out_file)
		return out_file;
#else
	TEXT* argv[20];
	TEXT** arg = argv;
	TEXT** const end = argv + FB_NELEM(argv) - 1; // The last element should be NULL
	TEXT* pp = filename;
	while (*pp && arg < end) {
		*arg++ = pp;
		while (*pp && *pp != ' ')
			pp++;
		if (!*pp)
			break;
		*pp++ = 0;
		while (*pp == ' ')
			pp++;
	}
	*arg = NULL;

	int pair[2];
	if (pipe(pair) < 0)
		IBERROR(36);			// Msg36 couldn't create pipe

	if (!vfork()) {
		close(pair[1]);
		close(0);
		dup(pair[0]);
		close(pair[0]);
		execvp(argv[0], argv);
		ERRQ_msg_put(43, filename);	// Msg43 Couldn't run %s
		_exit(-1);
	}

	close(pair[0]);

	FILE* out_file = fdopen(pair[1], "w");
	if (out_file)
		return out_file;
#endif

	IBERROR(37);				// Msg37 fdopen failed
	return NULL;
}


void EXEC_poll_abort(void)
{
/**************************************
 *
 *	E X E C _ p o l l _ a b o r t
 *
 **************************************
 *
 * Functional description
 *	Poll for abort flag (actually, most routines will check the
 *	flag before calling to save time).
 *
 **************************************/

	if (!QLI_abort)
		return;

	IBERROR(38);				// Msg38 execution terminated by signal
}


DSC *EXEC_receive(qli_msg* message, qli_par* parameter)
{
/**************************************
 *
 *	E X E C _ r e c e i v e
 *
 **************************************
 *
 * Functional description
 *	Receive a message from a running request.
 *
 **************************************/
	ISC_STATUS_ARRAY status_vector;

	qli_req* request = message->msg_request;

	if (isc_receive(status_vector, &request->req_handle, message->msg_number,
					 message->msg_length, message->msg_buffer, 0))
	{
		db_error(request, status_vector);
	}

	if (!parameter)
		return NULL;

	return EVAL_parameter(parameter);
}


void EXEC_send( qli_msg* message)
{
/**************************************
 *
 *	E X E C _ s e n d
 *
 **************************************
 *
 * Functional description
 *	Send a message to a running request.  First, however, map
 *	any data to the message.
 *
 **************************************/
	ISC_STATUS_ARRAY status_vector;

	qli_req* request = message->msg_request;

	map_data(message);
	if (isc_send(status_vector, &request->req_handle, message->msg_number,
				  message->msg_length, message->msg_buffer, 0))
	{
		db_error(request, status_vector);
	}
}


void EXEC_start_request( qli_req* request, qli_msg* message)
{
/**************************************
 *
 *	E X E C _ s t a r t _ r e q u e s t
 *
 **************************************
 *
 * Functional description
 *	Start a request running.  If there is a message to be sent, do
 *	a start and send.
 *
 **************************************/
	ISC_STATUS_ARRAY status_vector;

	if (message) 
	{
		map_data(message);
		if (!isc_start_and_send(status_vector, &request->req_handle,
								 &request->req_database-> dbb_transaction,
								 message->msg_number, message->msg_length,
								 message->msg_buffer, 0))
		{
			return;
		}
	}
	else 
	{
		if (!isc_start_request(status_vector, &request->req_handle,
								&request->req_database-> dbb_transaction, 0))
		{
			return;
		}
	}

	db_error(request, status_vector);
}


void EXEC_top( qli_nod* node)
{
/**************************************
 *
 *	E X E C _ t o p
 *
 **************************************
 *
 * Functional description
 *	Execute a node type.
 *
 **************************************/

	EXEC_execute(node);
}


static DSC *assignment(	qli_nod*		from_node,
						DSC*	to_desc,
						qli_nod*		validation,
						qli_nod*		initial,
						qli_par*		parameter)
{
/**************************************
 *
 *	a s s i g n m e n t
 *
 **************************************
 *
 * Functional description
 *	Evaluate an expression and perform an assignment.  If something
 *	goes wrong and there was a prompt, try again.
 *
 **************************************/
	jmp_buf old_env;

	memcpy(old_env, QLI_env, sizeof(QLI_env));
	QLI_reprompt = FALSE;
	QLI_prompt_count = 0;

	USHORT trash;
	USHORT* missing_flag = &trash;
	qli_msg* message = NULL;
	if (parameter) {
		message = parameter->par_message;
		missing_flag =
			(USHORT *) (message->msg_buffer + parameter->par_offset);
	}

	try {

		memcpy(QLI_env, old_env, sizeof(QLI_env));
		dsc* from_desc = EVAL_value(from_node);

		if (from_desc->dsc_missing & DSC_initial) {
			from_desc = EVAL_value(initial);
		}

/* If there is a value present, do any assignment; otherwise null fill */

		if (*missing_flag = to_desc->dsc_missing = from_desc->dsc_missing) 
		{
			if (from_desc->dsc_length)
				memset(from_desc->dsc_address, 0, from_desc->dsc_length);
		}
		else {
			MOVQ_move(from_desc, to_desc);
		}

		if (validation && EVAL_boolean(validation) <= 0) {
			IBERROR(39);			// Msg39 field validation error
		}

		QLI_reprompt = FALSE;
		memcpy(QLI_env, old_env, sizeof(QLI_env));

		return from_desc;

	}
	catch (const Firebird::Exception&) {
		if (QLI_abort || !QLI_prompt_count) {
			memcpy(QLI_env, old_env, sizeof(QLI_env));
			throw;
		}

		QLI_reprompt = TRUE;
		QLI_prompt_count = 0;
		return NULL;
	}
}


static void commit_retaining( qli_nod* node)
{
/**************************************
 *
 *	c o m m i t _ r e t a i n i n g
 *
 **************************************
 *
 * Functional description
 *	Execute commit retaining statement for
 *	one or more named databases or all databases.
 *	If there's more than one, prepare it.
 *
 **************************************/

/* If there aren't any open databases then obviously
   there isn't anything to commit. */

	if (node->nod_count == 0 && !QLI_databases)
		return;

	if (node->nod_type == nod_commit_retaining &&
		((node->nod_count > 1) ||
		 (node->nod_count == 0 && QLI_databases->dbb_next)))
	{
		node->nod_type = nod_prepare;
		commit_retaining(node);
		node->nod_type = nod_commit_retaining;
	}
	else if (node->nod_count == 1) {
		DBB database = (DBB) node->nod_arg[0];
		database->dbb_flags |= DBB_prepared;
	}
	else
		QLI_databases->dbb_flags |= DBB_prepared;


	if (node->nod_count == 0) {
		for (DBB database = QLI_databases; database;
			 database = database->dbb_next)
		{
			if ((node->nod_type == nod_commit_retaining)
				&& !(database->dbb_flags & DBB_prepared))
			{
				ERRQ_msg_put(465, database->dbb_symbol->sym_string);
			}
			else if (node->nod_type == nod_prepare)
				database->dbb_flags |= DBB_prepared;
			if (database->dbb_transaction)
				transaction_state(node, database);
		}
		return;
	}

    qli_nod** ptr = node->nod_arg;
	for (const qli_nod* const* const end = ptr + node->nod_count; ptr < end; ptr++)
	{
		DBB database = (DBB) *ptr;
		if ((node->nod_type == nod_commit_retaining) &&
			!(database->dbb_flags & DBB_prepared))
		{
			ERRQ_msg_put(465, database->dbb_symbol->sym_string);
		}
		else if (node->nod_type == nod_prepare)
			database->dbb_flags |= DBB_prepared;
		if (database->dbb_transaction)
			transaction_state(node, database);
	}
}



static bool copy_blob( qli_nod* value, qli_par* parameter)
{
/**************************************
 *
 *	 c o p y _ b l o b
 *
 **************************************
 *
 * Functional description
 *	Copy a blob from one database to another.  If the blob can be
 *	successfully assigned, return false and let somebody else just
 *	copy the blob ids.
 *
 **************************************/

/* If assignment isn't from a field, there isn't a blob copy, so
   do a dumb assignment. */

	if (value->nod_type != nod_field)
		return false;

/* Find the sending and receiving requests.  If they are the same
   and no filtering is necessary, a simple assignment will suffice. */

	qli_ctx* context = (qli_ctx*) value->nod_arg[e_fld_context];
	qli_req* from_request = context->ctx_request;
	DBB from_dbb = from_request->req_database;
	qli_msg* message = parameter->par_message;
	qli_req* to_request = message->msg_request;
	DBB to_dbb = to_request->req_database;

	dsc* from_desc = EVAL_value(value);
	dsc* to_desc = EVAL_parameter(parameter);

	if (to_dbb == from_dbb &&
		(!to_desc->dsc_sub_type ||
		 from_desc->dsc_sub_type == to_desc->dsc_sub_type))
	{
		return false;
	}

	// We've got a blob copy on our hands.

	if (!from_desc) {
		*to_desc->dsc_address = 0;
		return true;
	}


	// Format blob parameter block for the existing blob

	UCHAR bpb[20];
	UCHAR* p = bpb;
	*p++ = isc_bpb_version1;
	*p++ = isc_bpb_source_type;
	*p++ = 2;
	*p++ = from_desc->dsc_sub_type;
	*p++ = from_desc->dsc_sub_type >> 8;
	*p++ = isc_bpb_target_type;
	*p++ = 2;
	*p++ = to_desc->dsc_sub_type;
	*p++ = to_desc->dsc_sub_type >> 8;
	const USHORT bpb_length = p - bpb;

	ISC_STATUS_ARRAY status_vector;
	UserBlob to_blob(status_vector);
	UserBlob from_blob(status_vector);
	
	if (!to_blob.create(to_dbb->dbb_handle, to_dbb->dbb_transaction,
						 *(ISC_QUAD*) to_desc->dsc_address))
	{
		ERRQ_database_error(to_dbb, status_vector);
	}

	if (!from_blob.open(from_dbb->dbb_handle, from_dbb->dbb_transaction,
						*(ISC_QUAD*) from_desc->dsc_address, bpb_length,
						bpb))
	{
		ERRQ_database_error(from_dbb, status_vector);
	}

	SLONG size, segment_count, max_segment;
	if (!getBlobSize(from_blob, &size, &segment_count, &max_segment))
		ERRQ_database_error(from_dbb, status_vector);

    UCHAR fixed_buffer[4096];
	UCHAR* buffer;
	USHORT buffer_length;
	if (max_segment < (SLONG) sizeof(fixed_buffer)) {
		buffer_length = sizeof(fixed_buffer);
		buffer = fixed_buffer;
	}
	else
	{
		buffer_length = max_segment;
		buffer = (UCHAR*) gds__alloc(buffer_length);
#ifdef DEBUG_GDS_ALLOC
		// We don't care about QLI specific memory leaks for V4.0
		gds_alloc_flag_unfreed((void *) buffer);	// QLI: don't care
#endif
	}

	size_t length;
	while (from_blob.getSegment(buffer_length, buffer, length) && !from_blob.getCode())
	{
		if (!to_blob.putSegment(length, buffer))
		{
			ERRQ_database_error(to_dbb, status_vector);
		}
	}

	if (buffer != fixed_buffer)
		gds__free(buffer);

	if (!from_blob.close())
		ERRQ_database_error(from_dbb, status_vector);

	if (!to_blob.close())
		ERRQ_database_error(to_dbb, status_vector);

	return true;
}


static void db_error( qli_req* request, ISC_STATUS * status_vector)
{
/**************************************
 *
 *	d b _ e r r o r
 *
 **************************************
 *
 * Functional description
 *	A database error has occurred.  Unless it was the result of
 *	an unwind, generate an error.
 *
 **************************************/

	EXEC_poll_abort();
	ERRQ_database_error(request->req_database, status_vector);
}


static void execute_abort( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ a b o r t
 *
 **************************************
 *
 * Functional description
 *	Abort a statement.
 *
 **************************************/
	if (node->nod_count) {
	    const TEXT* ptr = NULL;
		UCHAR temp[80];
		const USHORT l =
			MOVQ_get_string(EVAL_value(node->nod_arg[0]), &ptr,
				(vary*) temp, sizeof(temp));

		UCHAR msg[128];
		MOVQ_terminate(ptr, (SCHAR*) msg, l, sizeof(msg));
		ERRQ_error(40, SafeArg() << msg);
		// Msg40 Request terminated by statement: %s
	}

	IBERROR(41);				// Msg41 Request terminated by statement
}


static void execute_assignment( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ a s s i g n m e n t
 *
 **************************************
 *
 * Functional description
 *
 **************************************/
	if (node->nod_flags & NOD_remote)
		return;

	qli_nod* to = node->nod_arg[e_asn_to];
	qli_nod* from = node->nod_arg[e_asn_from];
	qli_nod* initial = node->nod_arg[e_asn_initial];

	qli_par* parameter;
	if (to->nod_type == nod_field) {
		qli_nod* reference = to->nod_arg[e_fld_reference];
		parameter = reference->nod_import;
		if (to->nod_desc.dsc_dtype == dtype_blob &&
			from->nod_desc.dsc_dtype == dtype_blob &&
			copy_blob(from, parameter))
		{
			return;
		}
	}
	else
		parameter = node->nod_import;

	if (parameter)
		parameter = parameter->par_missing;

	assignment(from, EVAL_value(to),
			   node->nod_arg[e_asn_valid], initial, parameter);

// propagate the missing flag in variable assignments

	if (to->nod_type == nod_variable) {
		qli_fld* field = (qli_fld*) to->nod_arg[e_fld_field];
		if (to->nod_desc.dsc_missing & DSC_missing)
			field->fld_flags |= FLD_missing;
		else
			field->fld_flags &= ~FLD_missing;
	}
}


static void execute_for( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ f o r
 *
 **************************************
 *
 * Functional description
 *	Execute a FOR loop.  This may require that a request get
 *	started, a message sent, and a message received for each
 *	record.  At the other end of the spectrum, there may be
 *	absolutely nothing to do.
 *
 **************************************/

/* If there is a request associated  with the node, start it and possibly
   send a message along with it. */

	qli_req* request = (qli_req*) node->nod_arg[e_for_request];
	if (request)
		EXEC_start_request(request, (qli_msg*) node->nod_arg[e_for_send]);
	else {
	    qli_msg* amessage = (qli_msg*) node->nod_arg[e_for_send];
		if (amessage)
			EXEC_send(amessage);
	}

/* If there isn't a receive message, the body of the loop has been
   optimized out of existence.  So skip it. */

	qli_msg* message = (qli_msg*) node->nod_arg[e_for_receive];
	if (!message)
		goto count;

/* Receive messages in a loop until the end of file field comes up
   true. */

	while (true) {
		dsc* desc = EXEC_receive(message, (qli_par*) node->nod_arg[e_for_eof]);
		if (*(USHORT *) desc->dsc_address)
			break;
		EXEC_execute(node->nod_arg[e_for_statement]);
		if (request && request->req_continue)
			EXEC_send(request->req_continue);
	}

  count:
	if (QLI_count)
		print_counts(request);
}


static void execute_modify( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ m o d i f y
 *
 **************************************
 *
 * Functional description
 *	Execute a modify statement.  This probably involves sending a
 *	message to the running request and executing a sub-statement.
 *
 **************************************/
	if (node->nod_flags & NOD_remote)
		return;

	qli_msg* message = (qli_msg*) node->nod_arg[e_mod_send];
	if (message)
		set_null(message);

	EXEC_execute(node->nod_arg[e_mod_statement]);

	if (message)
		EXEC_send(message);
}


static void execute_output( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ o u t p u t
 *
 **************************************
 *
 * Functional description
 *	Open output stream to re-direct output.
 *
 **************************************/
	qli_prt* print = (qli_prt*) node->nod_arg[e_out_print];
	print->prt_file = EXEC_open_output(node);

	// Set up error handling

	jmp_buf old_env;
	jmp_buf env;
	memcpy(old_env, QLI_env, sizeof(QLI_env));
	memcpy(QLI_env, env, sizeof(QLI_env));

	try {

		// Finally, execute the query

		EXEC_execute(node->nod_arg[e_out_statement]);
		memcpy(QLI_env, old_env, sizeof(QLI_env));
		fclose(print->prt_file);

	}
	catch (const Firebird::Exception&) {
		if (print->prt_file) {
			fclose(print->prt_file);
		}
		memcpy(QLI_env, old_env, sizeof(QLI_env));
		throw;
	}
}


static void execute_print( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ p r i n t
 *
 **************************************
 *
 * Functional description
 *	Execute a print statement.  Since the loop has been factored
 *	out, this should be easy.
 *
 **************************************/

	if (node->nod_arg[e_prt_header]) {
		FMT_put((TEXT*) node->nod_arg[e_prt_header], (qli_prt*) node->nod_arg[e_prt_output]);
		node->nod_arg[e_prt_header] = NULL;
	}

	FMT_print(node->nod_arg[e_prt_list], (qli_prt*) node->nod_arg[e_prt_output]);
}


static void execute_repeat( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ r e p e a t
 *
 **************************************
 *
 * Functional description
 *	Execute a REPEAT statement.  In short, loop.
 *
 **************************************/
	SLONG count = MOVQ_get_long(EVAL_value(node->nod_arg[e_rpt_value]), 0);

	while (--count >= 0)
		EXEC_execute(node->nod_arg[e_rpt_statement]);
}


static void execute_store( qli_nod* node)
{
/**************************************
 *
 *	e x e c u t e _ s t o r e
 *
 **************************************
 *
 * Functional description
 *	Execute a STORE statement.  This may involve starting
 *	a request, sending a message, and executing a sub-statement.
 *	On the other hand, it may be a mody no-op if the statement
 *	is part of another request and doesn't need any data from
 *	here.
 *
 **************************************/
	qli_msg* message = (qli_msg*) node->nod_arg[e_sto_send];
	if (message)
		set_null(message);

	if (!(node->nod_flags & NOD_remote))
		EXEC_execute(node->nod_arg[e_sto_statement]);

/* If there is a request associated  with the node, start it and possibly
   send a message along with it. */

	qli_req* request = (qli_req*) node->nod_arg[e_sto_request];
	if (request)
		EXEC_start_request(request, (qli_msg*) node->nod_arg[e_sto_send]);
	else if (message)
		EXEC_send(message);

	if (QLI_count)
		print_counts(request);
}


static void map_data( qli_msg* message)
{
/**************************************
 *
 *	m a p _ d a t a
 *
 **************************************
 *
 * Functional description
 *	Map data to a message in preparation for sending.
 *
 **************************************/
	for (qli_par* parameter = message->msg_parameters; parameter;
		 parameter = parameter->par_next)
	{
		dsc* desc = &parameter->par_desc;
		desc->dsc_address = message->msg_buffer + parameter->par_offset;
		qli_par* missing_parameter = parameter->par_missing;
		if (missing_parameter) {
			USHORT* missing_flag = (USHORT*) (message->msg_buffer +
							missing_parameter->par_offset);
			*missing_flag = (desc->dsc_missing & DSC_missing) ? DSC_missing : 0;
		}

		qli_nod* from = parameter->par_value;
		if (desc->dsc_dtype == dtype_blob && copy_blob(from, parameter))
			continue;
		assignment(from, desc, 0, 0, parameter->par_missing);
	}
}


static void print_counts( qli_req* request)
{
/**************************************
 *
 *	p r i n t _ c o u n t s
 *
 **************************************
 *
 * Functional description
 *	Print out the count of records affected
 *	by the last statement.
 *
 **************************************/
	ISC_STATUS_ARRAY status_vector;

	UCHAR count_buffer[COUNT_ITEMS * 7 + 1];
	if (isc_request_info(status_vector, &request->req_handle, 0,
						  sizeof(count_info), count_info,
						  sizeof(count_buffer), (SCHAR*) count_buffer))
	{
		return;
	}

// print out the counts of any records affected

	int length = 0;
	for (UCHAR* c = count_buffer; *c != isc_info_end; c += length) {
		const UCHAR item = *c++;
		length = gds__vax_integer(c, 2);
		c += 2;
		const ULONG number = gds__vax_integer(c, length);

		if (number)
			switch (item) {
			case isc_info_req_select_count:
				printf("\nrecords selected: %"ULONGFORMAT"\n", number);
				break;

			case isc_info_req_insert_count:
				printf("records inserted: %"ULONGFORMAT"\n", number);
				break;

			case isc_info_req_update_count:
				printf("records updated: %"ULONGFORMAT"\n", number);
				break;

			case isc_info_req_delete_count:
				printf("records deleted: %"ULONGFORMAT"\n", number);
				break;

			default:
				return;
			}
	}
}


static void set_null( qli_msg* message)
{
/**************************************
 *
 *	s e t _ n u l l
 *
 **************************************
 *
 * Functional description
 *	Set all parameters of an outgoing
 *	message to null - this allows conditional
 *	assignments to work in store and modify
 *	statements.
 *
 **************************************/
	for (qli_par* parameter = message->msg_parameters; parameter;
		 parameter = parameter->par_next)
	{
		qli_nod* from = parameter->par_value;
		if (from->nod_type == nod_field) {
			dsc* desc = EVAL_value(from);
			desc->dsc_missing |= DSC_missing;
		}
		else
			from->nod_desc.dsc_missing |= DSC_missing;
	}
}



static void transaction_state( qli_nod* node, DBB database)
{
/**************************************
 *
 *	t r a n s a c t i o n _ s t a t e
 *
 **************************************
 *
 * Functional description
 *
 *	set the state of the working transaction
 *	in a particular database to prepared or
 *	committed.
 *
 **************************************/
	ISC_STATUS_ARRAY status;

	if (database->dbb_transaction) {
		if (node->nod_type == nod_commit_retaining) {
			if (isc_commit_retaining(status, &database->dbb_transaction))
					ERRQ_database_error(database, status);
		}
		else if (node->nod_type == nod_prepare) {
			if (isc_prepare_transaction(status, &database->dbb_transaction))
					ERRQ_database_error(database, status);
		}
	}
}