godot/core/io/file_access_memory.cpp
Rémi Verschelde 01d5c463be
FileAccess: Don't err in store_buffer with buffer of size 0
The error check was added for `FileAccessUnix` but it's not an error when both
`p_src` and `p_length` are zero.

Added correct error checks to all implementations to prevent the actual
erroneous case: `p_src` is nullptr but `p_length > 0` (risk of null pointer
indexing).

Fixes #33564.
2021-06-07 18:34:00 +02:00

181 lines
5.3 KiB
C++

/*************************************************************************/
/* file_access_memory.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* 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_memory.h"
#include "core/config/project_settings.h"
#include "core/os/dir_access.h"
#include "core/templates/map.h"
static Map<String, Vector<uint8_t>> *files = nullptr;
void FileAccessMemory::register_file(String p_name, Vector<uint8_t> p_data) {
if (!files) {
files = memnew((Map<String, Vector<uint8_t>>));
}
String name;
if (ProjectSettings::get_singleton()) {
name = ProjectSettings::get_singleton()->globalize_path(p_name);
} else {
name = p_name;
}
//name = DirAccess::normalize_path(name);
(*files)[name] = p_data;
}
void FileAccessMemory::cleanup() {
if (!files) {
return;
}
memdelete(files);
}
FileAccess *FileAccessMemory::create() {
return memnew(FileAccessMemory);
}
bool FileAccessMemory::file_exists(const String &p_name) {
String name = fix_path(p_name);
//name = DirAccess::normalize_path(name);
return files && (files->find(name) != nullptr);
}
Error FileAccessMemory::open_custom(const uint8_t *p_data, uint64_t p_len) {
data = (uint8_t *)p_data;
length = p_len;
pos = 0;
return OK;
}
Error FileAccessMemory::_open(const String &p_path, int p_mode_flags) {
ERR_FAIL_COND_V(!files, ERR_FILE_NOT_FOUND);
String name = fix_path(p_path);
//name = DirAccess::normalize_path(name);
Map<String, Vector<uint8_t>>::Element *E = files->find(name);
ERR_FAIL_COND_V_MSG(!E, ERR_FILE_NOT_FOUND, "Can't find file '" + p_path + "'.");
data = E->get().ptrw();
length = E->get().size();
pos = 0;
return OK;
}
void FileAccessMemory::close() {
data = nullptr;
}
bool FileAccessMemory::is_open() const {
return data != nullptr;
}
void FileAccessMemory::seek(uint64_t p_position) {
ERR_FAIL_COND(!data);
pos = p_position;
}
void FileAccessMemory::seek_end(int64_t p_position) {
ERR_FAIL_COND(!data);
pos = length + p_position;
}
uint64_t FileAccessMemory::get_position() const {
ERR_FAIL_COND_V(!data, 0);
return pos;
}
uint64_t FileAccessMemory::get_length() const {
ERR_FAIL_COND_V(!data, 0);
return length;
}
bool FileAccessMemory::eof_reached() const {
return pos > length;
}
uint8_t FileAccessMemory::get_8() const {
uint8_t ret = 0;
if (pos < length) {
ret = data[pos];
}
++pos;
return ret;
}
uint64_t FileAccessMemory::get_buffer(uint8_t *p_dst, uint64_t p_length) const {
ERR_FAIL_COND_V(!p_dst && p_length > 0, -1);
ERR_FAIL_COND_V(!data, -1);
uint64_t left = length - pos;
uint64_t read = MIN(p_length, left);
if (read < p_length) {
WARN_PRINT("Reading less data than requested");
}
memcpy(p_dst, &data[pos], read);
pos += p_length;
return read;
}
Error FileAccessMemory::get_error() const {
return pos >= length ? ERR_FILE_EOF : OK;
}
void FileAccessMemory::flush() {
ERR_FAIL_COND(!data);
}
void FileAccessMemory::store_8(uint8_t p_byte) {
ERR_FAIL_COND(!data);
ERR_FAIL_COND(pos >= length);
data[pos++] = p_byte;
}
void FileAccessMemory::store_buffer(const uint8_t *p_src, uint64_t p_length) {
ERR_FAIL_COND(!p_src && p_length > 0);
uint64_t left = length - pos;
uint64_t write = MIN(p_length, left);
if (write < p_length) {
WARN_PRINT("Writing less data than requested");
}
memcpy(&data[pos], p_src, write);
pos += p_length;
}