virtualx-engine/core/io/file_access_buffered.cpp
2014-02-09 22:10:30 -03:00

184 lines
5 KiB
C++

/*************************************************************************/
/* file_access_buffered.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#include "file_access_buffered.h"
#include <string.h>
#include "error_macros.h"
Error FileAccessBuffered::set_error(Error p_error) const {
return (last_error = p_error);
};
void FileAccessBuffered::set_cache_size(int p_size) {
cache_size = p_size;
};
int FileAccessBuffered::get_cache_size() {
return cache_size;
};
int FileAccessBuffered::cache_data_left() const {
if (file.offset >= file.size) {
return 0;
};
if (cache.offset == -1 || file.offset < cache.offset || file.offset >= cache.offset + cache.buffer.size()) {
return read_data_block(file.offset, cache_size);
} else {
return cache.buffer.size() - (file.offset - cache.offset);
};
return 0;
};
void FileAccessBuffered::seek(size_t p_position) {
file.offset = p_position;
};
void FileAccessBuffered::seek_end(int64_t p_position) {
file.offset = file.size + p_position;
};
size_t FileAccessBuffered::get_pos() const {
return file.offset;
};
size_t FileAccessBuffered::get_len() const {
return file.size;
};
bool FileAccessBuffered::eof_reached() const {
return file.offset > file.size;
};
uint8_t FileAccessBuffered::get_8() const {
ERR_FAIL_COND_V(!file.open,0);
uint8_t byte = 0;
if (cache_data_left() >= 1) {
byte = cache.buffer[file.offset - cache.offset];
};
++file.offset;
return byte;
};
int FileAccessBuffered::get_buffer(uint8_t *p_dest,int p_elements) const {
ERR_FAIL_COND_V(!file.open, -1);
if (p_elements > cache_size) {
int total_read = 0;
if (!(cache.offset == -1 || file.offset < cache.offset || file.offset >= cache.offset + cache.buffer.size())) {
int size = (cache.buffer.size() - (file.offset - cache.offset));
size = size - (size % 4);
//DVector<uint8_t>::Read read = cache.buffer.read();
//memcpy(p_dest, read.ptr() + (file.offset - cache.offset), size);
memcpy(p_dest, cache.buffer.ptr() + (file.offset - cache.offset), size);
p_dest += size;
p_elements -= size;
file.offset += size;
total_read += size;
};
int err = read_data_block(file.offset, p_elements, p_dest);
if (err >= 0) {
total_read += err;
file.offset += err;
};
return total_read;
};
int to_read = p_elements;
int total_read = 0;
while (to_read > 0) {
int left = cache_data_left();
if (left == 0) {
if (to_read > 0) {
file.offset += to_read;
};
return total_read;
};
if (left < 0) {
return left;
};
int r = MIN(left, to_read);
//DVector<uint8_t>::Read read = cache.buffer.read();
//memcpy(p_dest+total_read, &read.ptr()[file.offset - cache.offset], r);
memcpy(p_dest+total_read, cache.buffer.ptr() + (file.offset - cache.offset), r);
file.offset += r;
total_read += r;
to_read -= r;
};
return p_elements;
};
bool FileAccessBuffered::is_open() const {
return file.open;
};
Error FileAccessBuffered::get_error() const {
return last_error;
};
FileAccessBuffered::FileAccessBuffered() {
cache_size = DEFAULT_CACHE_SIZE;
};
FileAccessBuffered::~FileAccessBuffered(){
}