firebird-mirror/src/jrd/misc.cpp

/*
 *	PROGRAM:	JRD Access Method
 *	MODULE:		misc.c
 *	DESCRIPTION:	Miscellaneous routines
 *
 * 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): ______________________________________.
 */

#ifdef NETWARE_386
#include <sys/stat.h>
#include <errno.h>
#endif

#include "../jrd/ib_stdio.h"
#include <string.h>
#include "../jrd/common.h"
#include <stdarg.h>
#include "../jrd/dsc.h"
#include "../jrd/misc.h"
#include "../jrd/gds_proto.h"
#include "../jrd/misc_proto.h"

#define STUFF(p,value)		{*p++ = value;}
#define STUFF_BYTES(p,value,len) {memcpy (p, (SCHAR*) (value), len); p += len;}
#define STUFF_SHORT(p,value)	STUFF_BYTES (p, &value, sizeof (SSHORT))
#define STUFF_LONG(p,value)	STUFF_BYTES (p, &value, sizeof (SLONG))


SSHORT MISC_build_parameters_block(UCHAR * buffer, ...)
{
/**************************************
 *
 *	M I S C _ b u i l d _ p a r a m e t e r s _ b l o c k
 *
 **************************************
 *
 * Functional description
 *	Stuffs the passed buffer with various argument information coming via
 *	va_list.  An argument type of 0 signifies the end of argument list.
 *	Returns the total number of bytes put (stuffed) in the passed buffer.
 *
 **************************************/
	va_list ptr;
	UCHAR *p, *q;
	SCHAR arg_type, ch;
	USHORT sh;
	SLONG l;

	p = buffer;
	VA_START(ptr, buffer);

/* using the argument types in the parameter list, 
   pop the arguments off the call stack and put
   them into the passed buffer */

	while (arg_type = va_arg(ptr, SCHAR))
		switch (arg_type) {
		case dtype_byte:		/* byte */
			ch = va_arg(ptr, SCHAR);
			STUFF(p, ch);
			break;

		case dtype_short:		/* short value */
			sh = va_arg(ptr, USHORT);
			STUFF_SHORT(p, sh);
			break;

		case dtype_long:		/* long value */
			l = (SLONG) va_arg(ptr, SLONG);
			STUFF_LONG(p, l);
			break;

		case dtype_cstring:	/* null-terminated string */
			q = va_arg(ptr, UCHAR *);
			STUFF_BYTES(p, q, strlen(reinterpret_cast < char *>(q)) + 1);
			break;

		case dtype_varying:	/* short value followed by a value with that many bytes */
			sh = va_arg(ptr, USHORT);
			STUFF_SHORT(p, sh);
			q = va_arg(ptr, UCHAR *);
			STUFF_BYTES(p, q, sh);
			break;
		}

	va_end(ptr);

	return (p - buffer);
}


#ifdef DEV_BUILD
ULONG MISC_checksum_log_rec(UCHAR * header,
							SSHORT h_len, UCHAR * data, SSHORT d_len)
{
/**************************************
 *
 *      M I S C _ c h e c k s u m _ l o g _ r e c
 *
 **************************************
 *
 * Functional description
 *      Checksum a log record - header and data are passed separately.
 *
 **************************************/
	ULONG checksum;
	UCHAR *p;

	checksum = 0;

	if (h_len) {
		p = header;
		do
			checksum += *p++;
		while (--h_len);
	}

	if (d_len) {
		p = data;
		do
			checksum += *p++;
		while (--d_len);
	}

	return checksum;
}
#endif /* DEV_BUILD */


#ifdef NETWARE_386
SCHAR *MISC_mktemp(SCHAR * filename, SCHAR * prefix)
{
/**************************************
 *
 *      M I S C _ m k t e m p
 *
 **************************************
 *
 * Functional description
 *      mktemp for NLM.
 *      filename points to a directory name and a prefix.
 *
 **************************************/
	SCHAR local_fname[256];
	struct stat statblk;
	SSHORT prefix_len;
	SCHAR name[L_tmpnam];

	prefix_len = strlen(prefix);
	if (prefix_len > 4) {		/* Limit the prefix to 4 charaters to leave some space 
								   for temp file subscript */
		filename[strlen(filename) - (prefix_len - 4)] = '\0';
		prefix_len = 4;
	}

	for (;;) {
		ib_tmpnam(name);
		/* Create a full directory path name for a temp file */
		sprintf(local_fname, "%s%s", filename, &name[prefix_len]);
		/* Make sure that the file does not already exist */
		if ((stat(local_fname, &statblk) == -1) && (errno == ENOENT)) {
			strcpy(filename, local_fname);
			return filename;
		}
	}
}
#endif


UCHAR *MISC_pop(STK * stack)
{
/**************************************
 *
 *	M I S C _ p o p 
 *
 **************************************
 *
 * Functional description
 *	Pops an object off a linked list stack.
 *	Returns the address of the popped object.
 *
 **************************************/
	STK node;
	UCHAR *object;

	node = *stack;
	object = node->stk_object;
	*stack = node->stk_next;
	gds__free(node);

	return object;
}


STK MISC_push(UCHAR * object, STK * stack)
{
/**************************************
 *
 *	M I S C _ p u s h 
 *
 **************************************
 *
 * Functional description
 *	Push an object on the passed stack. 
 *	Returns the address of the new top of the stack.
 *
 **************************************/
	STK node;

	node = (STK) gds__alloc((SLONG) sizeof(struct stk));
/* FREE: in MISC_pop(), NOMEM: return a NULL top of stack */
	if (!node)
		return NULL;
	node->stk_object = object;
	node->stk_next = *stack;
	*stack = node;

	return node;
}