gzguts.h revision 206708 
1/* gzguts.h -- zlib internal header definitions for gz* operations
2 * Copyright (C) 2004, 2005, 2010 Mark Adler
3 * For conditions of distribution and use, see copyright notice in zlib.h
4 */
5
6#ifdef _LARGEFILE64_SOURCE
7#  ifndef _LARGEFILE_SOURCE
8#    define _LARGEFILE_SOURCE 1
9#  endif
10#  ifdef _FILE_OFFSET_BITS
11#    undef _FILE_OFFSET_BITS
12#  endif
13#endif
14
15#define ZLIB_INTERNAL
16
17#include <stdio.h>
18#include "zlib.h"
19#ifdef STDC
20#  include <string.h>
21#  include <stdlib.h>
22#  include <limits.h>
23#endif
24#include <fcntl.h>
25
26#ifdef NO_DEFLATE       /* for compatibility with old definition */
27#  define NO_GZCOMPRESS
28#endif
29
30#ifdef _MSC_VER
31#  include <io.h>
32#  define vsnprintf _vsnprintf
33#endif
34
35#ifndef local
36#  define local static
37#endif
38/* compile with -Dlocal if your debugger can't find static symbols */
39
40/* gz* functions always use library allocation functions */
41#ifndef STDC
42  extern voidp  malloc OF((uInt size));
43  extern void   free   OF((voidpf ptr));
44#endif
45
46/* get errno and strerror definition */
47#if defined UNDER_CE
48#  include <windows.h>
49#  define zstrerror() gz_strwinerror((DWORD)GetLastError())
50#else
51#  ifdef STDC
52#    include <errno.h>
53#    define zstrerror() strerror(errno)
54#  else
55#    define zstrerror() "stdio error (consult errno)"
56#  endif
57#endif
58
59/* provide prototypes for these when building zlib without LFS */
60#if !defined(_LARGEFILE64_SOURCE) || _LFS64_LARGEFILE-0 == 0
61    ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
62    ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
63    ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
64    ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
65#endif
66
67/* default i/o buffer size -- double this for output when reading */
68#define GZBUFSIZE 8192
69
70/* gzip modes, also provide a little integrity check on the passed structure */
71#define GZ_NONE 0
72#define GZ_READ 7247
73#define GZ_WRITE 31153
74#define GZ_APPEND 1     /* mode set to GZ_WRITE after the file is opened */
75
76/* values for gz_state how */
77#define LOOK 0      /* look for a gzip header */
78#define COPY 1      /* copy input directly */
79#define GZIP 2      /* decompress a gzip stream */
80
81/* internal gzip file state data structure */
82typedef struct {
83        /* used for both reading and writing */
84    int mode;               /* see gzip modes above */
85    int fd;                 /* file descriptor */
86    char *path;             /* path or fd for error messages */
87    z_off64_t pos;          /* current position in uncompressed data */
88    unsigned size;          /* buffer size, zero if not allocated yet */
89    unsigned want;          /* requested buffer size, default is GZBUFSIZE */
90    unsigned char *in;      /* input buffer */
91    unsigned char *out;     /* output buffer (double-sized when reading) */
92    unsigned char *next;    /* next output data to deliver or write */
93        /* just for reading */
94    unsigned have;          /* amount of output data unused at next */
95    int eof;                /* true if end of input file reached */
96    z_off64_t start;        /* where the gzip data started, for rewinding */
97    z_off64_t raw;          /* where the raw data started, for seeking */
98    int how;                /* 0: get header, 1: copy, 2: decompress */
99    int direct;             /* true if last read direct, false if gzip */
100        /* just for writing */
101    int level;              /* compression level */
102    int strategy;           /* compression strategy */
103        /* seek request */
104    z_off64_t skip;         /* amount to skip (already rewound if backwards) */
105    int seek;               /* true if seek request pending */
106        /* error information */
107    int err;                /* error code */
108    char *msg;              /* error message */
109        /* zlib inflate or deflate stream */
110    z_stream strm;          /* stream structure in-place (not a pointer) */
111} gz_state;
112typedef gz_state FAR *gz_statep;
113
114/* shared functions */
115ZEXTERN void ZEXPORT gz_error OF((gz_statep, int, const char *));
116#if defined UNDER_CE
117ZEXTERN char ZEXPORT *gz_strwinerror OF((DWORD error));
118#endif
119
120/* GT_OFF(x), where x is an unsigned value, is true if x > maximum z_off64_t
121   value -- needed when comparing unsigned to z_off64_t, which is signed
122   (possible z_off64_t types off_t, off64_t, and long are all signed) */
123#ifdef INT_MAX
124#  define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > INT_MAX)
125#else
126ZEXTERN unsigned ZEXPORT gz_intmax OF((void));
127#  define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())
128#endif
129