gzguts.h revision 206002 
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#if _LARGEFILE64_SOURCE == 1
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#if _LARGEFILE64_SOURCE == 1
60#  define z_off64_t off64_t
61#else
62#  define z_off64_t z_off_t
63#endif
64
65/* default i/o buffer size -- double this for output when reading */
66#define GZBUFSIZE 8192
67
68/* gzip modes, also provide a little integrity check on the passed structure */
69#define GZ_NONE 0
70#define GZ_READ 7247
71#define GZ_WRITE 31153
72#define GZ_APPEND 1     /* mode set to GZ_WRITE after the file is opened */
73
74/* values for gz_state how */
75#define LOOK 0      /* look for a gzip header */
76#define COPY 1      /* copy input directly */
77#define GZIP 2      /* decompress a gzip stream */
78
79/* internal gzip file state data structure */
80typedef struct {
81        /* used for both reading and writing */
82    int mode;               /* see gzip modes above */
83    int fd;                 /* file descriptor */
84    char *path;             /* path or fd for error messages */
85    z_off64_t pos;          /* current position in uncompressed data */
86    unsigned size;          /* buffer size, zero if not allocated yet */
87    unsigned want;          /* requested buffer size, default is GZBUFSIZE */
88    unsigned char *in;      /* input buffer */
89    unsigned char *out;     /* output buffer (double-sized when reading) */
90    unsigned char *next;    /* next output data to deliver or write */
91        /* just for reading */
92    unsigned have;          /* amount of output data unused at next */
93    int eof;                /* true if end of input file reached */
94    z_off64_t start;        /* where the gzip data started, for rewinding */
95    z_off64_t raw;          /* where the raw data started, for seeking */
96    int how;                /* 0: get header, 1: copy, 2: decompress */
97    int direct;             /* true if last read direct, false if gzip */
98        /* just for writing */
99    int level;              /* compression level */
100    int strategy;           /* compression strategy */
101        /* seek request */
102    z_off64_t skip;         /* amount to skip (already rewound if backwards) */
103    int seek;               /* true if seek request pending */
104        /* error information */
105    int err;                /* error code */
106    char *msg;              /* error message */
107        /* zlib inflate or deflate stream */
108    z_stream strm;          /* stream structure in-place (not a pointer) */
109} gz_state;
110typedef gz_state FAR *gz_statep;
111
112/* shared functions */
113ZEXTERN void ZEXPORT gz_error OF((gz_statep, int, const char *));
114#if defined UNDER_CE
115ZEXTERN char ZEXPORT *gz_strwinerror OF((DWORD error));
116#endif
117
118/* GT_OFF(x), where x is an unsigned value, is true if x > maximum z_off64_t
119   value -- needed when comparing unsigned to z_off64_t, which is signed
120   (possible z_off64_t types off_t, off64_t, and long are all signed) */
121#ifdef INT_MAX
122#  define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > INT_MAX)
123#else
124ZEXTERN unsigned ZEXPORT gz_intmax OF((void));
125#  define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())
126#endif
127