modules/zlib/src/gzguts.h

   1 /* gzguts.h -- zlib internal header definitions for gz* operations
   2  * Copyright (C) 2004-2024 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 #  undef _FILE_OFFSET_BITS
  11 #  undef _TIME_BITS
  12 #endif
  13
  14 #ifdef HAVE_HIDDEN
  15 #  define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
  16 #else
  17 #  define ZLIB_INTERNAL
  18 #endif
  19
  20 #include <stdio.h>
  21 #include "zlib.h"
  22 #ifdef STDC
  23 #  include <string.h>
  24 #  include <stdlib.h>
  25 #  include <limits.h>
  26 #endif
  27
  28 #ifndef _POSIX_SOURCE
  29 #  define _POSIX_SOURCE
  30 #endif
  31 #include <fcntl.h>
  32
  33 #ifdef _WIN32
  34 #  include <stddef.h>
  35 #endif
  36
  37 #if defined(__TURBOC__) || defined(_MSC_VER) || defined(_WIN32)
  38 #  include <io.h>
  39 #endif
  40
  41 #if defined(_WIN32)
  42 #  define WIDECHAR
  43 #endif
  44
  45 #ifdef WINAPI_FAMILY
  46 #  define open _open
  47 #  define read _read
  48 #  define write _write
  49 #  define close _close
  50 #endif
  51
  52 #ifdef NO_DEFLATE       /* for compatibility with old definition */
  53 #  define NO_GZCOMPRESS
  54 #endif
  55
  56 #if defined(STDC99) || (defined(__TURBOC__) && __TURBOC__ >= 0x550)
  57 #  ifndef HAVE_VSNPRINTF
  58 #    define HAVE_VSNPRINTF
  59 #  endif
  60 #endif
  61
  62 #if defined(__CYGWIN__)
  63 #  ifndef HAVE_VSNPRINTF
  64 #    define HAVE_VSNPRINTF
  65 #  endif
  66 #endif
  67
  68 #if defined(MSDOS) && defined(__BORLANDC__) && (BORLANDC > 0x410)
  69 #  ifndef HAVE_VSNPRINTF
  70 #    define HAVE_VSNPRINTF
  71 #  endif
  72 #endif
  73
  74 #ifndef HAVE_VSNPRINTF
  75 #  ifdef MSDOS
  76 /* vsnprintf may exist on some MS-DOS compilers (DJGPP?),
  77    but for now we just assume it doesn't. */
  78 #    define NO_vsnprintf
  79 #  endif
  80 #  ifdef __TURBOC__
  81 #    define NO_vsnprintf
  82 #  endif
  83 #  ifdef WIN32
  84 /* In Win32, vsnprintf is available as the "non-ANSI" _vsnprintf. */
  85 #    if !defined(vsnprintf) && !defined(NO_vsnprintf)
  86 #      if !defined(_MSC_VER) || ( defined(_MSC_VER) && _MSC_VER < 1500 )
  87 #         define vsnprintf _vsnprintf
  88 #      endif
  89 #    endif
  90 #  endif
  91 #  ifdef __SASC
  92 #    define NO_vsnprintf
  93 #  endif
  94 #  ifdef VMS
  95 #    define NO_vsnprintf
  96 #  endif
  97 #  ifdef __OS400__
  98 #    define NO_vsnprintf
  99 #  endif
 100 #  ifdef __MVS__
 101 #    define NO_vsnprintf
 102 #  endif
 103 #endif
 104
 105 /* unlike snprintf (which is required in C99), _snprintf does not guarantee
 106    null termination of the result -- however this is only used in gzlib.c where
 107    the result is assured to fit in the space provided */
 108 #if defined(_MSC_VER) && _MSC_VER < 1900
 109 #  define snprintf _snprintf
 110 #endif
 111
 112 #ifndef local
 113 #  define local static
 114 #endif
 115 /* since "static" is used to mean two completely different things in C, we
 116    define "local" for the non-static meaning of "static", for readability
 117    (compile with -Dlocal if your debugger can't find static symbols) */
 118
 119 /* gz* functions always use library allocation functions */
 120 #ifndef STDC
 121   extern voidp  malloc(uInt size);
 122   extern void   free(voidpf ptr);
 123 #endif
 124
 125 /* get errno and strerror definition */
 126 #if defined UNDER_CE
 127 #  include <windows.h>
 128 #  define zstrerror() gz_strwinerror((DWORD)GetLastError())
 129 #else
 130 #  ifndef NO_STRERROR
 131 #    include <errno.h>
 132 #    define zstrerror() strerror(errno)
 133 #  else
 134 #    define zstrerror() "stdio error (consult errno)"
 135 #  endif
 136 #endif
 137
 138 /* provide prototypes for these when building zlib without LFS */
 139 #if !defined(_LARGEFILE64_SOURCE) || _LFS64_LARGEFILE-0 == 0
 140     ZEXTERN gzFile ZEXPORT gzopen64(const char *, const char *);
 141     ZEXTERN z_off64_t ZEXPORT gzseek64(gzFile, z_off64_t, int);
 142     ZEXTERN z_off64_t ZEXPORT gztell64(gzFile);
 143     ZEXTERN z_off64_t ZEXPORT gzoffset64(gzFile);
 144 #endif
 145
 146 /* default memLevel */
 147 #if MAX_MEM_LEVEL >= 8
 148 #  define DEF_MEM_LEVEL 8
 149 #else
 150 #  define DEF_MEM_LEVEL  MAX_MEM_LEVEL
 151 #endif
 152
 153 /* default i/o buffer size -- double this for output when reading (this and
 154    twice this must be able to fit in an unsigned type) */
 155 #define GZBUFSIZE 8192
 156
 157 /* gzip modes, also provide a little integrity check on the passed structure */
 158 #define GZ_NONE 0
 159 #define GZ_READ 7247
 160 #define GZ_WRITE 31153
 161 #define GZ_APPEND 1     /* mode set to GZ_WRITE after the file is opened */
 162
 163 /* values for gz_state how */
 164 #define LOOK 0      /* look for a gzip header */
 165 #define COPY 1      /* copy input directly */
 166 #define GZIP 2      /* decompress a gzip stream */
 167
 168 /* internal gzip file state data structure */
 169 typedef struct {
 170         /* exposed contents for gzgetc() macro */
 171     struct gzFile_s x;      /* "x" for exposed */
 172                             /* x.have: number of bytes available at x.next */
 173                             /* x.next: next output data to deliver or write */
 174                             /* x.pos: current position in uncompressed data */
 175         /* used for both reading and writing */
 176     int mode;               /* see gzip modes above */
 177     int fd;                 /* file descriptor */
 178     char *path;             /* path or fd for error messages */
 179     unsigned size;          /* buffer size, zero if not allocated yet */
 180     unsigned want;          /* requested buffer size, default is GZBUFSIZE */
 181     unsigned char *in;      /* input buffer (double-sized when writing) */
 182     unsigned char *out;     /* output buffer (double-sized when reading) */
 183     int direct;             /* 0 if processing gzip, 1 if transparent */
 184         /* just for reading */
 185     int how;                /* 0: get header, 1: copy, 2: decompress */
 186     z_off64_t start;        /* where the gzip data started, for rewinding */
 187     int eof;                /* true if end of input file reached */
 188     int past;               /* true if read requested past end */
 189         /* just for writing */
 190     int level;              /* compression level */
 191     int strategy;           /* compression strategy */
 192     int reset;              /* true if a reset is pending after a Z_FINISH */
 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;
 202 typedef gz_state FAR *gz_statep;
 203
 204 /* shared functions */
 205 void ZLIB_INTERNAL gz_error(gz_statep, int, const char *);
 206 #if defined UNDER_CE
 207 char ZLIB_INTERNAL *gz_strwinerror(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 unsigned ZLIB_INTERNAL gz_intmax(void);
 214 #define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())