ref: 56a4d87cb2935339e970d0743c250389fc4706c8
dir: /src/lzw/zopen.h/
/* $NetBSD: zopen.c,v 1.8 2003/08/07 11:13:29 agc Exp $ */
/*-
* Copyright (c) 1985, 1986, 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Diomidis Spinellis and James A. Woods, derived from original
* work by Spencer Thomas and Joseph Orost.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*-
*
* Copyright (c) 2004
* Albert Chin-A-Young.
*
* Modified to work with FreeType's PCF driver.
*
*/
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)zopen.c 8.1 (Berkeley) 6/27/93";
#else
static char rcsid[] = "$NetBSD: zopen.c,v 1.8 2003/08/07 11:13:29 agc Exp $";
#endif
#endif /* LIBC_SCCS and not lint */
#include <stdio.h>
#define BITS 16 /* Default bits. */
#define HSIZE 69001 /* 95% occupancy */
/* A code_int must be able to hold 2**BITS values of type int, and also -1. */
typedef long code_int;
typedef long count_int;
typedef unsigned char char_type;
typedef enum {
S_START, S_MIDDLE, S_EOF
} zs_enum;
typedef struct {
unsigned char *next_in;
unsigned int avail_in;
unsigned long total_in;
unsigned char *next_out;
unsigned int avail_out;
unsigned long total_out;
zs_enum zs_state; /* State of computation */
int zs_n_bits; /* Number of bits/code. */
int zs_maxbits; /* User settable max # bits/code. */
code_int zs_maxcode; /* Maximum code, given n_bits. */
code_int zs_maxmaxcode; /* Should NEVER generate this code. */
count_int zs_htab [HSIZE];
unsigned short zs_codetab [HSIZE];
code_int zs_hsize; /* For dynamic table sizing. */
code_int zs_free_ent; /* First unused entry. */
/*
* Block compression parameters -- after all codes are used up,
* and compression rate changes, start over.
*/
int zs_block_compress;
int zs_clear_flg;
int zs_offset;
long zs_in_count; /* Remaining uncompressed bytes. */
char_type zs_buf_len;
char_type zs_buf[BITS]; /* Temporary buffer if we need
to read more to accumulate
n_bits. */
union {
struct {
char_type *zs_stackp;
int zs_finchar;
code_int zs_code, zs_oldcode, zs_incode;
int zs_roffset, zs_size;
char_type zs_gbuf[BITS];
} r; /* Read parameters */
} u;
} s_zstate_t;
static code_int getcode(s_zstate_t *);
#if 0
static int zclose(s_zstate_t *);
#endif
static void zinit(s_zstate_t *);
static int zread(s_zstate_t *);