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      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) || defined(__CYGWIN__)
     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 */
    170 typedef 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;
    202 typedef gz_state FAR *gz_statep;
    203 
    204 /* shared functions */
    205 void ZLIB_INTERNAL gz_error OF((gz_statep, int, const char *));
    206 #if defined UNDER_CE
    207 char 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
    216 unsigned ZLIB_INTERNAL gz_intmax OF((void));
    217 #  define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())
    218 #endif
    219