firebird-mirror/src/remote/merge.cpp

/*
 *	PROGRAM:	JRD Remote Interface/Server
 *	MODULE:		merge.c
 *	DESCRIPTION:	Merge database/server inforation
 *
 * 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 <string.h>
#include "../include/jrd/gds.h"
#include "../remote/remote.h"
#include "../remote/merge_proto.h"
#include "../jrd/gds_proto.h"

#define PUT_WORD(ptr, value)	{*(ptr)++ = value; *(ptr)++ = value >> 8;}
#define PUT(ptr, value)		*(ptr)++ = value;

static SSHORT convert(ULONG, UCHAR *);
static STATUS merge_setup(UCHAR **, UCHAR **, UCHAR *, USHORT);


USHORT DLL_EXPORT MERGE_database_info(
									  UCHAR * in,
									  UCHAR * out,
									  USHORT out_length,
									  USHORT impl,
USHORT class_, USHORT base_level, UCHAR * version, UCHAR * id, ULONG mask)
{
/**************************************
 *
 *	M E R G E _ d a t a b a s e _ i n f o
 *
 **************************************
 *
 * Functional description
 *	Merge server / remote interface / Y-valve information into
 *	database block.  Return the actual length of the packet.
 *
 **************************************/
	SSHORT length, l;
	UCHAR *start, *end, *p;

	start = out;
	end = out + out_length;

	for (;;)
		switch (*out++ = *in++) {
		case gds_info_end:
		case gds_info_truncated:
			return out - start;

		case gds_info_version:
			l = strlen((char *) (p = version));
			if (merge_setup(&in, &out, end, l + 1))
				return 0;
			if ((*out++ = (UCHAR) l) != NULL)
				do
					*out++ = *p++;
				while (--l);
			break;

		case gds_info_db_id:
			l = strlen((SCHAR *) (p = id));
			if (merge_setup(&in, &out, end, l + 1))
				return 0;
			if ((*out++ = (UCHAR) l) != NULL)
				do
					*out++ = *p++;
				while (--l);
			break;

		case gds_info_implementation:
			if (merge_setup(&in, &out, end, 2))
				return 0;
			PUT(out, (UCHAR) impl);
			PUT(out, (UCHAR) class_);
			break;

		case gds_info_base_level:
			if (merge_setup(&in, &out, end, 1))
				return 0;
			PUT(out, (UCHAR) base_level);
			break;

		default:
			length = (SSHORT) gds__vax_integer(in, 2);
			in += 2;
			if (out + length + 2 >= end) {
				out[-1] = gds_info_truncated;
				return 0;
			}
			PUT_WORD(out, (UCHAR) length);
			if (length)
				do
					*out++ = *in++;
				while (--length);
			break;
		}
}


static SSHORT convert( ULONG number, UCHAR * buffer)
{
/**************************************
 *
 *	c o n v e r t
 *
 **************************************
 *
 * Functional description
 *	Convert a number to VAX form -- least significant bytes first.
 *	Return the length.
 *
 **************************************/
	ULONG n;
	UCHAR *p;

#ifdef VAX
	n = number;
	p = (UCHAR *) & n;
	*buffer++ = *p++;
	*buffer++ = *p++;
	*buffer++ = *p++;
	*buffer++ = *p++;

#else

	p = (UCHAR *) & number;
	p += 3;
	*buffer++ = *p--;
	*buffer++ = *p--;
	*buffer++ = *p--;
	*buffer++ = *p;

#endif

	return 4;
}


static STATUS merge_setup(
						  UCHAR ** in,
						  UCHAR ** out, UCHAR * end, USHORT delta_length)
{
/**************************************
 *
 *	m e r g e _ s e t u p
 *
 **************************************
 *
 * Functional description
 *	Get ready to toss new stuff onto an info packet.  This involves
 *	picking up and bumping the "count" field and copying what is
 *	already there.
 *
 **************************************/
	USHORT length, new_length, count;

	length = (USHORT) gds__vax_integer(*in, 2);
	new_length = length + delta_length;

	if (*out + new_length + 2 >= end) {
		(*out)[-1] = gds_info_truncated;
		return FAILURE;
	}

	*in += 2;
	count = 1 + *(*in)++;
	PUT_WORD(*out, (UCHAR) new_length);
	PUT(*out, (UCHAR) count);

/* Copy data portion of information sans original count */

	if (--length)
		do
			*(*out)++ = *(*in)++;
		while (--length);

	return SUCCESS;
}