1/* gzguts.h -- zlib internal header definitions for gz* operations
2 * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 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#ifdef HAVE_HIDDEN
16# define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
17#else
18# define ZLIB_INTERNAL
19#endif
20
21#include <stdio.h>
22#include "zlib.h"
23#ifdef STDC
24# include <string.h>
25# include <stdlib.h>
26# include <limits.h>
27#endif
28
29#ifndef _POSIX_SOURCE
30# define _POSIX_SOURCE
31#endif
32#include <fcntl.h>
33
34#ifdef _WIN32
35# include <stddef.h>
36#endif
37
38#if defined(__TURBOC__) || defined(_MSC_VER) || defined(_WIN32)
39# include <io.h>
40#endif
41
42#if defined(_WIN32)
43# define WIDECHAR
44#endif
45
46#ifdef WINAPI_FAMILY
47# define open _open
48# define read _read
49# define write _write
50# define close _close
51#endif
52
53#ifdef NO_DEFLATE /* for compatibility with old definition */
54# define NO_GZCOMPRESS
55#endif
56
57#if defined(STDC99) || (defined(__TURBOC__) && __TURBOC__ >= 0x550)
58# ifndef HAVE_VSNPRINTF
59# define HAVE_VSNPRINTF
60# endif
61#endif
62
63#if defined(__CYGWIN__)
64# ifndef HAVE_VSNPRINTF
65# define HAVE_VSNPRINTF
66# endif
67#endif
68
69#if defined(MSDOS) && defined(__BORLANDC__) && (BORLANDC > 0x410)
70# ifndef HAVE_VSNPRINTF
71# define HAVE_VSNPRINTF
72# endif
73#endif
74
75#ifndef HAVE_VSNPRINTF
76# ifdef MSDOS
77/* vsnprintf may exist on some MS-DOS compilers (DJGPP?),
78 but for now we just assume it doesn't. */
79# define NO_vsnprintf
80# endif
81# ifdef __TURBOC__
82# define NO_vsnprintf
83# endif
84# ifdef WIN32
85/* In Win32, vsnprintf is available as the "non-ANSI" _vsnprintf. */
86# if !defined(vsnprintf) && !defined(NO_vsnprintf)
87# if !defined(_MSC_VER) || ( defined(_MSC_VER) && _MSC_VER < 1500 )
88# define vsnprintf _vsnprintf
89# endif
90# endif
91# endif
92# ifdef __SASC
93# define NO_vsnprintf
94# endif
95# ifdef VMS
96# define NO_vsnprintf
97# endif
98# ifdef __OS400__
99# define NO_vsnprintf
100# endif
101# ifdef __MVS__
102# define NO_vsnprintf
103# endif
104#endif
105
106/* unlike snprintf (which is required in C99), _snprintf does not guarantee
107 null termination of the result -- however this is only used in gzlib.c where
108 the result is assured to fit in the space provided */
109#if defined(_MSC_VER) && _MSC_VER < 1900
110# define snprintf _snprintf
111#endif
112
113#ifndef local
114# define local static
115#endif
116/* since "static" is used to mean two completely different things in C, we
117 define "local" for the non-static meaning of "static", for readability
118 (compile with -Dlocal if your debugger can't find static symbols) */
119
120/* gz* functions always use library allocation functions */
121#ifndef STDC
122 extern voidp malloc OF((uInt size));
123 extern void free OF((voidpf ptr));
124#endif
125
126/* get errno and strerror definition */
127#if defined UNDER_CE
128# include <windows.h>
129# define zstrerror() gz_strwinerror((DWORD)GetLastError())
130#else
131# ifndef NO_STRERROR
132# include <errno.h>
133# define zstrerror() strerror(errno)
134# else
135# define zstrerror() "stdio error (consult errno)"
136# endif
137#endif
138
139/* provide prototypes for these when building zlib without LFS */
140#if !defined(_LARGEFILE64_SOURCE) || _LFS64_LARGEFILE-0 == 0
141 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
142 ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
143 ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
144 ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
145#endif
146
147/* default memLevel */
148#if MAX_MEM_LEVEL >= 8
149# define DEF_MEM_LEVEL 8
150#else
151# define DEF_MEM_LEVEL MAX_MEM_LEVEL
152#endif
153
154/* default i/o buffer size -- double this for output when reading (this and
155 twice this must be able to fit in an unsigned type) */
156#define GZBUFSIZE 8192
157
158/* gzip modes, also provide a little integrity check on the passed structure */
159#define GZ_NONE 0
160#define GZ_READ 7247
161#define GZ_WRITE 31153
162#define GZ_APPEND 1 /* mode set to GZ_WRITE after the file is opened */
163
164/* values for gz_state how */
165#define LOOK 0 /* look for a gzip header */
166#define COPY 1 /* copy input directly */
167#define GZIP 2 /* decompress a gzip stream */
168
169/* internal gzip file state data structure */
170typedef struct {
171 /* exposed contents for gzgetc() macro */
172 struct gzFile_s x; /* "x" for exposed */
173 /* x.have: number of bytes available at x.next */
174 /* x.next: next output data to deliver or write */
175 /* x.pos: current position in uncompressed data */
176 /* used for both reading and writing */
177 int mode; /* see gzip modes above */
178 int fd; /* file descriptor */
179 char *path; /* path or fd for error messages */
180 unsigned size; /* buffer size, zero if not allocated yet */
181 unsigned want; /* requested buffer size, default is GZBUFSIZE */
182 unsigned char *in; /* input buffer (double-sized when writing) */
183 unsigned char *out; /* output buffer (double-sized when reading) */
184 int direct; /* 0 if processing gzip, 1 if transparent */
185 /* just for reading */
186 int how; /* 0: get header, 1: copy, 2: decompress */
187 z_off64_t start; /* where the gzip data started, for rewinding */
188 int eof; /* true if end of input file reached */
189 int past; /* true if read requested past end */
190 /* just for writing */
191 int level; /* compression level */
192 int strategy; /* compression strategy */
193 /* seek request */
194 z_off64_t skip; /* amount to skip (already rewound if backwards) */
195 int seek; /* true if seek request pending */
196 /* error information */
197 int err; /* error code */
198 char *msg; /* error message */
199 /* zlib inflate or deflate stream */
200 z_stream strm; /* stream structure in-place (not a pointer) */
201} gz_state;
202typedef gz_state FAR *gz_statep;
203
204/* shared functions */
205void ZLIB_INTERNAL gz_error OF((gz_statep, int, const char *));
206#if defined UNDER_CE
207char ZLIB_INTERNAL *gz_strwinerror OF((DWORD error));
208#endif
209
210/* GT_OFF(x), where x is an unsigned value, is true if x > maximum z_off64_t
211 value -- needed when comparing unsigned to z_off64_t, which is signed
212 (possible z_off64_t types off_t, off64_t, and long are all signed) */
213#ifdef INT_MAX
214# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > INT_MAX)
215#else
216unsigned ZLIB_INTERNAL gz_intmax OF((void));
217# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())
218#endif
219

source code of zlib/gzguts.h