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Diffstat (limited to 'src/lzw/ftzopen.h')
| -rw-r--r-- | src/lzw/ftzopen.h | 171 |
1 files changed, 0 insertions, 171 deletions
diff --git a/src/lzw/ftzopen.h b/src/lzw/ftzopen.h deleted file mode 100644 index 9788114..0000000 --- a/src/lzw/ftzopen.h +++ /dev/null @@ -1,171 +0,0 @@ -/***************************************************************************/ -/* */ -/* ftzopen.h */ -/* */ -/* FreeType support for .Z compressed files. */ -/* */ -/* This optional component relies on NetBSD's zopen(). It should mainly */ -/* be used to parse compressed PCF fonts, as found with many X11 server */ -/* distributions. */ -/* */ -/* Copyright 2005, 2006, 2007 by David Turner. */ -/* */ -/* This file is part of the FreeType project, and may only be used, */ -/* modified, and distributed under the terms of the FreeType project */ -/* license, LICENSE.TXT. By continuing to use, modify, or distribute */ -/* this file you indicate that you have read the license and */ -/* understand and accept it fully. */ -/* */ -/***************************************************************************/ - -#ifndef __FT_ZOPEN_H__ -#define __FT_ZOPEN_H__ - -#include <ft2build.h> -#include FT_FREETYPE_H - - - /* - * This is a complete re-implementation of the LZW file reader, - * since the old one was incredibly badly written, using - * 400 KByte of heap memory before decompressing anything. - * - */ - -#define FT_LZW_IN_BUFF_SIZE 64 -#define FT_LZW_DEFAULT_STACK_SIZE 64 - -#define LZW_INIT_BITS 9 -#define LZW_MAX_BITS 16 - -#define LZW_CLEAR 256 -#define LZW_FIRST 257 - -#define LZW_BIT_MASK 0x1f -#define LZW_BLOCK_MASK 0x80 -#define LZW_MASK( n ) ( ( 1U << (n) ) - 1U ) - - - typedef enum - { - FT_LZW_PHASE_START = 0, - FT_LZW_PHASE_CODE, - FT_LZW_PHASE_STACK, - FT_LZW_PHASE_EOF - - } FT_LzwPhase; - - - /* - * state of LZW decompressor - * - * small technical note - * -------------------- - * - * We use a few tricks in this implementation that are explained here to - * ease debugging and maintenance. - * - * - First of all, the `prefix' and `suffix' arrays contain the suffix - * and prefix for codes over 256; this means that - * - * prefix_of(code) == state->prefix[code-256] - * suffix_of(code) == state->suffix[code-256] - * - * Each prefix is a 16-bit code, and each suffix an 8-bit byte. - * - * Both arrays are stored in a single memory block, pointed to by - * `state->prefix'. This means that the following equality is always - * true: - * - * state->suffix == (FT_Byte*)(state->prefix + state->prefix_size) - * - * Of course, state->prefix_size is the number of prefix/suffix slots - * in the arrays, corresponding to codes 256..255+prefix_size. - * - * - `free_ent' is the index of the next free entry in the `prefix' - * and `suffix' arrays. This means that the corresponding `next free - * code' is really `256+free_ent'. - * - * Moreover, `max_free' is the maximum value that `free_ent' can reach. - * - * `max_free' corresponds to `(1 << max_bits) - 256'. Note that this - * value is always <= 0xFF00, which means that both `free_ent' and - * `max_free' can be stored in an FT_UInt variable, even on 16-bit - * machines. - * - * If `free_ent == max_free', you cannot add new codes to the - * prefix/suffix table. - * - * - `num_bits' is the current number of code bits, starting at 9 and - * growing each time `free_ent' reaches the value of `free_bits'. The - * latter is computed as follows - * - * if num_bits < max_bits: - * free_bits = (1 << num_bits)-256 - * else: - * free_bits = max_free + 1 - * - * Since the value of `max_free + 1' can never be reached by - * `free_ent', `num_bits' cannot grow larger than `max_bits'. - */ - - typedef struct _FT_LzwStateRec - { - FT_LzwPhase phase; - FT_Int in_eof; - - FT_Byte buf_tab[16]; - FT_Int buf_offset; - FT_Int buf_size; - FT_Bool buf_clear; - FT_Int buf_total; - - FT_UInt max_bits; /* max code bits, from file header */ - FT_Int block_mode; /* block mode flag, from file header */ - FT_UInt max_free; /* (1 << max_bits) - 256 */ - - FT_UInt num_bits; /* current code bit number */ - FT_UInt free_ent; /* index of next free entry */ - FT_UInt free_bits; /* if reached by free_ent, increment num_bits */ - FT_UInt old_code; - FT_UInt old_char; - FT_UInt in_code; - - FT_UShort* prefix; /* always dynamically allocated / reallocated */ - FT_Byte* suffix; /* suffix = (FT_Byte*)(prefix + prefix_size) */ - FT_UInt prefix_size; /* number of slots in `prefix' or `suffix' */ - - FT_Byte* stack; /* character stack */ - FT_UInt stack_top; - FT_UInt stack_size; - FT_Byte stack_0[FT_LZW_DEFAULT_STACK_SIZE]; /* minimize heap alloc */ - - FT_Stream source; /* source stream */ - FT_Memory memory; - - } FT_LzwStateRec, *FT_LzwState; - - - FT_LOCAL( void ) - ft_lzwstate_init( FT_LzwState state, - FT_Stream source ); - - FT_LOCAL( void ) - ft_lzwstate_done( FT_LzwState state ); - - - FT_LOCAL( void ) - ft_lzwstate_reset( FT_LzwState state ); - - - FT_LOCAL( FT_ULong ) - ft_lzwstate_io( FT_LzwState state, - FT_Byte* buffer, - FT_ULong out_size ); - -/* */ - -#endif /* __FT_ZOPEN_H__ */ - - -/* END */ |