mirror of
https://github.com/thepigeongenerator/mcaselector-lite
synced 2026-02-08 07:33:35 +01:00
Quinn
f5784844a8
These headers have no associated C files, and are mainly used for utility logic. Having them in `/include` makes them more easily located, and more globally used. We are using "classic" header guards here over `#pragma once` for better support. Since `#pragma once` is defined by the compiler, rather than standard C. Why isn't it used across the project? I have no idea.
60 lines
2.9 KiB
C
60 lines
2.9 KiB
C
/* This file is part of MCA-Selector-lite,
|
|
* and is licensed under GPL-2.0-only.
|
|
* Copyright (C)2025 quinnthepigeon@proton.me Quinn
|
|
* For further information, view COPYING and CONTRIBUTORS
|
|
* at: www.github.com/thepigeongenerator/mcaselector-lite */
|
|
#pragma once
|
|
|
|
#include <assert.h>
|
|
#include <mcaselector-lite/atrb.h>
|
|
#include <mcaselector-lite/endian.h>
|
|
#include <mcaselector-lite/types.h>
|
|
#include <stdbool.h>
|
|
#include <stdlib.h>
|
|
|
|
|
|
/* NBT (named binary tag) is a tree data structure. Tags have a numeric type ID, name and a payload.
|
|
* NBT files are a compressed `compound` tag. GZip is the compression used in most cases,
|
|
* in some (rare) cases it's stored uncompressed.
|
|
* A tag is an individual part of the data tree.
|
|
* The first byte is the ID, followed by a `u16`, for the length of the name.
|
|
* Then the name as `UTF-8`. (end tag does not contain name) */
|
|
|
|
|
|
/* specifies the NBT tag IDs.
|
|
* NOTE: every type is stored as BE (big-endian) in the file. */
|
|
enum nbt_tagid {
|
|
NBT_END = 0x00, // signifies the end of a compound tag
|
|
NBT_I8 = 0x01, // next byte is for an 8 bit signed integer.
|
|
NBT_I16 = 0x02, // next 2 bytes are for a 16 bit signed integer
|
|
NBT_I32 = 0x03, // next 4 bytes are for a 32 bit signed integer
|
|
NBT_I64 = 0x04, // next 8 bytes are for a 64 bit signed integer
|
|
NBT_F32 = 0x05, // next 4 bytes are for a single-precision floating-point
|
|
NBT_F64 = 0x06, // next 8 bytes are for a double-precision floating-point
|
|
NBT_ARR_I8 = 0x07, // starts with a i32, denoting size, followed by the i8 data
|
|
NBT_STR = 0x08, // starts with a u16, denoting size, followed by the UTF-8 data
|
|
NBT_LIST = 0x09, // starts with an ID, followed by a 32 bit signed integer denoting the size
|
|
NBT_COMPOUND = 0x0A, // compound tag, contains tags and is delimited by `NBT_END`
|
|
NBT_ARR_I32 = 0x0B, // starts with a i32, denoting size, followed by the i32 data
|
|
NBT_ARR_I64 = 0x0C, // starts with a i32, denoting size, followed by the u32 data
|
|
};
|
|
|
|
struct nbt_array {
|
|
s32 nmemb;
|
|
void *dat;
|
|
};
|
|
|
|
|
|
/* Acquires the data contained by the named tag.
|
|
* - `buf` points to the start of the tag.
|
|
* - `slen` contains the string length of the name.
|
|
* - `out` points to where the data should be written.
|
|
* if `buf` points to `NBT_I8`, `NBT_I16`, `NBT_I32`, `NBT_I64`, `NBT_F32`, or `NBT_F64`, `*out` is assumed
|
|
* to have the available byte width for one of these types. In the case of `NBT_ARR*` and `NBT_LIST`
|
|
* it must point to a `struct nbt_array*`. Where in the case of `NBT_LIST`, it must be one of the previous static-width types. */
|
|
const u8 *nbt_proctag(const u8 *restrict buf, u16 slen, void *restrict out) NONNULL((1, 3));
|
|
|
|
/* searches for the end of a named tag without processing data, the final pointer is returned.
|
|
* `NULL` is returned upon failure, the otherwise returned pointer is not guaranteed to be valid. */
|
|
const u8 *nbt_nexttag(const u8 *restrict buf) NONNULL((1)) PURE;
|