/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * Contributors: Amorilia (amorilia@users.sourceforge.net)
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/imbuf/intern/dds/Stream.cpp
 *  \ingroup imbdds
 */


#include <Stream.h>

#include <stdio.h>  // printf
#include <string.h> // memcpy

static const char *msg_error_seek = "DDS: trying to seek beyond end of stream (corrupt file?)";
static const char *msg_error_read = "DDS: trying to read beyond end of stream (corrupt file?)";

unsigned int Stream::seek(unsigned int p)
{
	if (p > size) {
		puts(msg_error_seek);
	}
	else {
		pos = p;
	}

	return pos;
}

unsigned int mem_read(Stream & mem, unsigned long long & i)
{
	if (mem.pos + 8 > mem.size) {
		puts(msg_error_seek);
		return(0);
	}
	memcpy(&i, mem.mem + mem.pos, 8); // @@ todo: make sure little endian
	mem.pos += 8;
	return(8);
}

unsigned int mem_read(Stream & mem, unsigned int & i)
{
	if (mem.pos + 4 > mem.size) {
		puts(msg_error_read);
		return(0);
	}
	memcpy(&i, mem.mem + mem.pos, 4); // @@ todo: make sure little endian
	mem.pos += 4;
	return(4);
}

unsigned int mem_read(Stream & mem, unsigned short & i)
{
	if (mem.pos + 2 > mem.size) {
		puts(msg_error_read);
		return(0);
	}
	memcpy(&i, mem.mem + mem.pos, 2); // @@ todo: make sure little endian
	mem.pos += 2;
	return(2);
}

unsigned int mem_read(Stream & mem, unsigned char & i)
{
	if (mem.pos + 1 > mem.size) {
		puts(msg_error_read);
		return(0);
	}
	i = (mem.mem + mem.pos)[0];
	mem.pos += 1;
	return(1);
}

unsigned int mem_read(Stream & mem, unsigned char *i, unsigned int cnt)
{
	if (mem.pos + cnt > mem.size) {
		puts(msg_error_read);
		return(0);
	}
	memcpy(i, mem.mem + mem.pos, cnt);
	mem.pos += cnt;
	return(cnt);
}