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