godot/core/io/resource_uid.cpp
reduz 8b7c7f5a75 Add a new HashMap implementation
Adds a new, cleaned up, HashMap implementation.

* Uses Robin Hood Hashing (https://en.wikipedia.org/wiki/Hash_table#Robin_Hood_hashing).
* Keeps elements in a double linked list for simpler, ordered, iteration.
* Allows keeping iterators for later use in removal (Unlike Map<>, it does not do much
  for performance vs keeping the key, but helps replace old code).
* Uses a more modern C++ iterator API, deprecates the old one.
* Supports custom allocator (in case there is a wish to use a paged one).

This class aims to unify all the associative template usage and replace it by this one:
* Map<> (whereas key order does not matter, which is 99% of cases)
* HashMap<>
* OrderedHashMap<>
* OAHashMap<>
2022-05-12 11:21:29 +02:00

262 lines
7.8 KiB
C++

/*************************************************************************/
/* resource_uid.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2022 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 "resource_uid.h"
#include "core/config/project_settings.h"
#include "core/crypto/crypto_core.h"
#include "core/io/dir_access.h"
#include "core/io/file_access.h"
static constexpr uint32_t char_count = ('z' - 'a');
static constexpr uint32_t base = char_count + ('9' - '0');
String ResourceUID::get_cache_file() {
return ProjectSettings::get_singleton()->get_project_data_path().plus_file("uid_cache.bin");
}
String ResourceUID::id_to_text(ID p_id) const {
if (p_id < 0) {
return "uid://<invalid>";
}
String txt;
while (p_id) {
uint32_t c = p_id % base;
if (c < char_count) {
txt = String::chr('a' + c) + txt;
} else {
txt = String::chr('0' + (c - char_count)) + txt;
}
p_id /= base;
}
return "uid://" + txt;
}
ResourceUID::ID ResourceUID::text_to_id(const String &p_text) const {
if (!p_text.begins_with("uid://") || p_text == "uid://<invalid>") {
return INVALID_ID;
}
uint32_t l = p_text.length();
uint64_t uid = 0;
for (uint32_t i = 6; i < l; i++) {
uid *= base;
uint32_t c = p_text[i];
if (is_ascii_lower_case(c)) {
uid += c - 'a';
} else if (is_digit(c)) {
uid += c - '0' + char_count;
} else {
return INVALID_ID;
}
}
return ID(uid & 0x7FFFFFFFFFFFFFFF);
}
ResourceUID::ID ResourceUID::create_id() {
while (true) {
ID id = INVALID_ID;
MutexLock lock(mutex);
Error err = ((CryptoCore::RandomGenerator *)crypto)->get_random_bytes((uint8_t *)&id, sizeof(id));
ERR_FAIL_COND_V(err != OK, INVALID_ID);
id &= 0x7FFFFFFFFFFFFFFF;
bool exists = unique_ids.has(id);
if (!exists) {
return id;
}
}
}
bool ResourceUID::has_id(ID p_id) const {
MutexLock l(mutex);
return unique_ids.has(p_id);
}
void ResourceUID::add_id(ID p_id, const String &p_path) {
MutexLock l(mutex);
ERR_FAIL_COND(unique_ids.has(p_id));
Cache c;
c.cs = p_path.utf8();
unique_ids[p_id] = c;
changed = true;
}
void ResourceUID::set_id(ID p_id, const String &p_path) {
MutexLock l(mutex);
ERR_FAIL_COND(!unique_ids.has(p_id));
CharString cs = p_path.utf8();
if (strcmp(cs.ptr(), unique_ids[p_id].cs.ptr()) != 0) {
unique_ids[p_id].cs = cs;
unique_ids[p_id].saved_to_cache = false; //changed
changed = true;
}
}
String ResourceUID::get_id_path(ID p_id) const {
MutexLock l(mutex);
ERR_FAIL_COND_V(!unique_ids.has(p_id), String());
const CharString &cs = unique_ids[p_id].cs;
return String::utf8(cs.ptr());
}
void ResourceUID::remove_id(ID p_id) {
MutexLock l(mutex);
ERR_FAIL_COND(!unique_ids.has(p_id));
unique_ids.erase(p_id);
}
Error ResourceUID::save_to_cache() {
String cache_file = get_cache_file();
if (!FileAccess::exists(cache_file)) {
Ref<DirAccess> d = DirAccess::create(DirAccess::ACCESS_RESOURCES);
d->make_dir_recursive(String(cache_file).get_base_dir()); //ensure base dir exists
}
Ref<FileAccess> f = FileAccess::open(cache_file, FileAccess::WRITE);
if (f.is_null()) {
return ERR_CANT_OPEN;
}
MutexLock l(mutex);
f->store_32(unique_ids.size());
cache_entries = 0;
for (KeyValue<ID, Cache> &E : unique_ids) {
f->store_64(E.key);
uint32_t s = E.value.cs.length();
f->store_32(s);
f->store_buffer((const uint8_t *)E.value.cs.ptr(), s);
E.value.saved_to_cache = true;
cache_entries++;
}
changed = false;
return OK;
}
Error ResourceUID::load_from_cache() {
Ref<FileAccess> f = FileAccess::open(get_cache_file(), FileAccess::READ);
if (f.is_null()) {
return ERR_CANT_OPEN;
}
MutexLock l(mutex);
unique_ids.clear();
uint32_t entry_count = f->get_32();
for (uint32_t i = 0; i < entry_count; i++) {
int64_t id = f->get_64();
int32_t len = f->get_32();
Cache c;
c.cs.resize(len + 1);
ERR_FAIL_COND_V(c.cs.size() != len + 1, ERR_FILE_CORRUPT); // out of memory
c.cs[len] = 0;
int32_t rl = f->get_buffer((uint8_t *)c.cs.ptrw(), len);
ERR_FAIL_COND_V(rl != len, ERR_FILE_CORRUPT);
c.saved_to_cache = true;
unique_ids[id] = c;
}
cache_entries = entry_count;
changed = false;
return OK;
}
Error ResourceUID::update_cache() {
if (!changed) {
return OK;
}
if (cache_entries == 0) {
return save_to_cache();
}
MutexLock l(mutex);
Ref<FileAccess> f;
for (KeyValue<ID, Cache> &E : unique_ids) {
if (!E.value.saved_to_cache) {
if (f.is_null()) {
f = FileAccess::open(get_cache_file(), FileAccess::READ_WRITE); //append
if (f.is_null()) {
return ERR_CANT_OPEN;
}
f->seek_end();
}
f->store_64(E.key);
uint32_t s = E.value.cs.length();
f->store_32(s);
f->store_buffer((const uint8_t *)E.value.cs.ptr(), s);
E.value.saved_to_cache = true;
cache_entries++;
}
}
if (f.is_valid()) {
f->seek(0);
f->store_32(cache_entries); //update amount of entries
}
changed = false;
return OK;
}
void ResourceUID::clear() {
cache_entries = 0;
unique_ids.clear();
changed = false;
}
void ResourceUID::_bind_methods() {
ClassDB::bind_method(D_METHOD("id_to_text", "id"), &ResourceUID::id_to_text);
ClassDB::bind_method(D_METHOD("text_to_id", "text_id"), &ResourceUID::text_to_id);
ClassDB::bind_method(D_METHOD("create_id"), &ResourceUID::create_id);
ClassDB::bind_method(D_METHOD("has_id", "id"), &ResourceUID::has_id);
ClassDB::bind_method(D_METHOD("add_id", "id", "path"), &ResourceUID::add_id);
ClassDB::bind_method(D_METHOD("set_id", "id", "path"), &ResourceUID::set_id);
ClassDB::bind_method(D_METHOD("get_id_path", "id"), &ResourceUID::get_id_path);
ClassDB::bind_method(D_METHOD("remove_id", "id"), &ResourceUID::remove_id);
BIND_CONSTANT(INVALID_ID)
}
ResourceUID *ResourceUID::singleton = nullptr;
ResourceUID::ResourceUID() {
ERR_FAIL_COND(singleton != nullptr);
singleton = this;
crypto = memnew(CryptoCore::RandomGenerator);
((CryptoCore::RandomGenerator *)crypto)->init();
}
ResourceUID::~ResourceUID() {
memdelete((CryptoCore::RandomGenerator *)crypto);
}