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