gif_lib_private.h revision c2eacaec90baee57fdbbdbad935d161638894ee7 
1#ifndef _GIF_LIB_PRIVATE_H
2#define _GIF_LIB_PRIVATE_H
3
4#include "gif_lib.h"
5#include "gif_hash.h"
6
7#define PROGRAM_NAME "GIFLIB"
8
9#ifdef SYSV
10#define VersionStr "Gif library module,\t\tEric S. Raymond\n\
11                    (C) Copyright 1997 Eric S. Raymond\n"
12#else
13#define VersionStr PROGRAM_NAME "    IBMPC " GIF_LIB_VERSION \
14                    "    Eric S. Raymond,    " __DATE__ ",   " \
15                    __TIME__ "\n" "(C) Copyright 1997 Eric S. Raymond\n"
16#endif /* SYSV */
17
18#define LZ_MAX_CODE         4095    /* Biggest code possible in 12 bits. */
19#define LZ_BITS             12
20
21#define FLUSH_OUTPUT        4096    /* Impossible code, to signal flush. */
22#define FIRST_CODE          4097    /* Impossible code, to signal first. */
23#define NO_SUCH_CODE        4098    /* Impossible code, to signal empty. */
24
25#define FILE_STATE_WRITE    0x01
26#define FILE_STATE_SCREEN   0x02
27#define FILE_STATE_IMAGE    0x04
28#define FILE_STATE_READ     0x08
29
30#define IS_READABLE(Private)    (Private->FileState & FILE_STATE_READ)
31#define IS_WRITEABLE(Private)   (Private->FileState & FILE_STATE_WRITE)
32
33typedef struct GifFilePrivateType {
34    GifWord FileState, FileHandle,  /* Where all this data goes to! */
35      BitsPerPixel,     /* Bits per pixel (Codes uses at least this + 1). */
36      ClearCode,   /* The CLEAR LZ code. */
37      EOFCode,     /* The EOF LZ code. */
38      RunningCode, /* The next code algorithm can generate. */
39      RunningBits, /* The number of bits required to represent RunningCode. */
40      MaxCode1,    /* 1 bigger than max. possible code, in RunningBits bits. */
41      LastCode,    /* The code before the current code. */
42      CrntCode,    /* Current algorithm code. */
43      StackPtr,    /* For character stack (see below). */
44      CrntShiftState;    /* Number of bits in CrntShiftDWord. */
45    unsigned long CrntShiftDWord;   /* For bytes decomposition into codes. */
46    unsigned long PixelCount;   /* Number of pixels in image. */
47    FILE *File;    /* File as stream. */
48    InputFunc Read;     /* function to read gif input (TVT) */
49    OutputFunc Write;   /* function to write gif output (MRB) */
50    GifByteType Buf[256];   /* Compressed input is buffered here. */
51    GifByteType Stack[LZ_MAX_CODE]; /* Decoded pixels are stacked here. */
52    GifByteType Suffix[LZ_MAX_CODE + 1];    /* So we can trace the codes. */
53    GifPrefixType Prefix[LZ_MAX_CODE + 1];
54    GifHashTableType *HashTable;
55} GifFilePrivateType;
56
57extern int _GifError;
58
59#endif /* _GIF_LIB_PRIVATE_H */
60