/*************************************************************************
* (C) 2021 AITNET ltd - Sofia/Bulgaria - <misho@aitnet.org>
*  by Michael Pounov <misho@elwix.org>
*
* $Author: misho $
* $Id: iov.c,v 1.2 2021/03/21 01:32:04 misho Exp $
*
**************************************************************************
The ELWIX and AITNET software is distributed under the following
terms:

All of the documentation and software included in the ELWIX and AITNET
Releases is copyrighted by ELWIX - Sofia/Bulgaria <info@elwix.org>

Copyright 2004 - 2021
	by Michael Pounov <misho@elwix.org>.  All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
   must display the following acknowledgement:
This product includes software developed by Michael Pounov <misho@elwix.org>
ELWIX - Embedded LightWeight unIX and its contributors.
4. Neither the name of AITNET nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
*/
#include "global.h"


/*
 * iov_Init() - Init new iovec array
 *
 * return: =NULL error, !=NULL ready array
 */
iovec_t *
iov_Init()
{
	iovec_t *iov;

	iov = e_malloc(sizeof(iovec_t));
	if (iov)
		memset(iov, 0, sizeof(iovec_t));

	return iov;
}

/*
 * iov_Destroy() - Destroy iovec array
 *
 * @iov = iovec array
 * return: none
 */
void
iov_Destroy(iovec_t ** __restrict iov)
{
	if (iov && *iov) {
		if ((*iov)->iov_array)
			e_free((*iov)->iov_array);
		e_free((*iov));
		*iov = NULL;
	}
}

/*
 * iov_Get() - Get data and length from position
 *
 * @iov = iovec array
 * @pos = position
 * @data = data
 * @datlen = data length
 * return: -1 error, 0 ok
 */
int
iov_Get(iovec_t * __restrict iov, u_int pos, void *data, size_t *datlen)
{
	if (!iov || !data || !datlen)
		return -1;

	if (pos >= iov->iov_size)
		return -1;

	*datlen = MIN(*datlen, iov->iov_array[pos].iov_len);
	memcpy(data, iov->iov_array[pos].iov_base, *datlen);

	return 0;
}

/*
 * iov_Insert() - Insert data at position into array
 *
 * @iov = iovec array
 * @pos = position
 * @data = data
 * @datlen = data length
 * return: -1 error, 0 ok
 */
int
iov_Insert(iovec_t * __restrict iov, u_int pos, void *data, size_t datlen)
{
	struct iovec *iv;

	if (!iov)
		return -1;

	if (pos >= iov->iov_size) {
		iv = e_realloc(iov->iov_array, sizeof(struct iovec) * (pos + 1));
		if (!iv)
			return -1;

		iov->iov_array = iv;
		iov->iov_size = pos + 1;
	}

	iov->iov_array[pos].iov_base = data;
	iov->iov_array[pos].iov_len = datlen;

	return 0;
}

/*
 * iov_Delete() - Delete data at position into array
 *
 * @iov = iovec array
 * @pos = position
 * @mustfree = data must be free before delete
 * return: -1 error, 0 ok
 */
int
iov_Delete(iovec_t * __restrict iov, u_int pos, int mustfree)
{
	if (!iov)
		return -1;

	if (pos < iov->iov_size) {
		if (mustfree)
			e_free(iov->iov_array[pos].iov_base);
		memset(iov->iov_array + pos, 0, sizeof(struct iovec));
	}

	return 0;
}

/*
 * iov_Push() - Push data on first free position
 *
 * @iov = iovec array
 * @data = data
 * @datlen = data length
 * return: -1 error, !=-1 pushed at position
 */
int
iov_Push(iovec_t * __restrict iov, void *data, size_t datlen)
{
	register int pos;

	if (!iov)
		return -1;

	for (pos = 0; pos < iov->iov_size; pos++)
		if (!iov->iov_array[pos].iov_len && !iov->iov_array[pos].iov_base)
			break;

	if (iov_Insert(iov, pos, data, datlen))
		return -1;

	return (int) pos;
}

/*
 * iov_Pop() - Pop data from last used position
 *
 * @iov = iovec array
 * @data = data
 * @datlen = data length
 * @mustfree = data must be free before delete
 * return: -1 error, !=-1 poped from position
 */
int
iov_Pop(iovec_t * __restrict iov, void *data, size_t *datlen, int mustfree)
{
	register int pos;

	if (!iov)
		return -1;

	if (iov->iov_size < 1)
		return 0;

	for (pos = iov->iov_size - 1; pos >= 0; pos--)
		if (iov->iov_array[pos].iov_base)
			break;

	iov_Get(iov, pos, data, datlen);
	iov_Delete(iov, pos, mustfree);
	return (int) pos;
}

/*
 * iov_PushPair() - Push pair/named data on first free position
 *
 * @iov = iovec array
 * @name = name of data
 * @data = data
 * @datlen = data length
 * return: -1 error, !=-1 pushed at position
 */
int
iov_PushPair(iovec_t * __restrict iov, const char *name, void *data, size_t datlen)
{
	char *str;
	int pos;

	if (!iov)
		return -1;

	str = e_strdup(name);
	if (!str)
		return -1;
	if (datlen == (size_t) -1) {
		if (data)
			datlen = strlen(data) + 1;
		else
			datlen = 0;
	}

	if ((pos = iov_Push(iov, str, strlen(str) + 1)) == -1) {
		e_free(str);
		return -1;
	}
	if (iov_Push(iov, data, datlen) == -1) {
		iov_Delete(iov, pos, 42);
		return -1;
	}

	return pos;
}

/*
 * iov_PopPair() - Pop pair/named data from last used position
 *
 * @iov = iovec array
 * @name = name of data
 * @namlen = name length
 * @data = data
 * @datlen = data length
 * @mustfree = data must be free before delete
 * return: -1 error, !=-1 poped from position
 */
int
iov_PopPair(iovec_t * __restrict iov, char *name, size_t *namlen, 
		void *data, size_t *datlen, int mustfree)
{
	int pos;

	if (!iov)
		return -1;

	if (iov_Pop(iov, data, datlen, mustfree) == -1)
		return -1;
	if ((pos = iov_Pop(iov, name, namlen, 42)) == -1)
		return -1;

	return pos;
}

/*
 * iov_FreePairs() - Free pairs/named data in iovec array
 *
 * @iov = iovec array
 * @mustfree = data must be free before delete
 * return: -1 error or 0 ok
 */
int
iov_FreePairs(iovec_t * __restrict iov, int mustfree)
{
	register int pos;

	if (!iov)
		return -1;

	if (iov->iov_size < 1)
		return 0;

	for (pos = 0; pos < (iov_Size(iov) & ~1); pos += 2) {
		if (iov->iov_array[pos].iov_base)
			iov_Delete(iov, pos, 42);
		if (iov->iov_array[pos + 1].iov_base)
			iov_Delete(iov, pos + 1, mustfree);
	}

	return 0;
}

/*
 * iov_Debug() - Debug of iovec array
 *
 * @iov = iovec array
 * return: none
 */
void
iov_Debug(iovec_t * __restrict iov)
{
	register size_t pos;

	if (!iov)
		return;

	printf("iov_size=%zu iov_array=%p\n", iov->iov_size, iov->iov_array);
	for (pos = 0; pos < iov->iov_size; pos++)
		printf("IOVEC[%zu] base=%p len=%zu (%s)\n", pos, iov->iov_array[pos].iov_base, 
				iov->iov_array[pos].iov_len, (char*) iov->iov_array[pos].iov_base);
}