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C

/*
* This file is part of the Aaru Data Preservation Suite.
* Copyright (c) 2019-2025 Natalia Portillo.
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of the
* License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef LZD_H
#define LZD_H
#include <stddef.h>
#include <stdint.h>
#define MAXBITS 13
#define MAXMAX ((1U << MAXBITS) - 1) // 8191
#define FIRST_FREE 258 // first free code after CLEAR+EOF
#define CLEAR 256
#define Z_EOF 257
typedef enum
{
LZD_OK = 0,
LZD_NEED_INPUT = 1,
LZD_NEED_OUTPUT = 2,
LZD_DONE = 3
} LZDStatus;
typedef struct
{
int * head;
uint8_t *tail;
unsigned nbits;
unsigned max_code;
unsigned free_code;
unsigned old_code;
int have_old;
char *stack;
char *stack_lim;
char *stack_ptr;
uint64_t bitbuf;
int bitcount;
const unsigned char *in_ptr;
size_t in_len;
size_t in_pos;
} LZDContext;
static const unsigned masks[MAXBITS + 1] = {
0,
0,
0,
0,
0,
0,
0,
0,
0,
(1u << 9) - 1,
(1u << 10) - 1,
(1u << 11) - 1,
(1u << 12) - 1,
(1u << 13) - 1
};
LZDStatus LZD_Init(LZDContext *ctx);
LZDStatus LZD_Feed(LZDContext *ctx, const unsigned char *in, size_t in_len);
LZDStatus LZD_Drain(LZDContext *ctx, unsigned char *out, size_t out_len, size_t *out_produced);
void LZD_Destroy(LZDContext *ctx);
#endif // LZD_H