gzguts.h

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/* gzguts.h -- zlib internal header definitions for gz* operations
 * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

#ifdef _LARGEFILE64_SOURCE
# ifndef _LARGEFILE_SOURCE
# define _LARGEFILE_SOURCE 1
# endif
# ifdef _FILE_OFFSET_BITS
# undef _FILE_OFFSET_BITS
# endif
#endif

#ifdef HAVE_HIDDEN
# define ZLIB_INTERNAL __attribute__((visibility ("hidden")))
#else
# define ZLIB_INTERNAL
#endif

#include <stdio.h>
#include "zlib.h"
#ifdef STDC
# include <string.h>
# include <stdlib.h>
# include <limits.h>
#endif
#include <fcntl.h>

#ifdef _WIN32
# include <stddef.h>
#endif

#if defined(__TURBOC__) || defined(_MSC_VER) || defined(_WIN32)
# include <io.h>
#endif

#ifdef WINAPI_FAMILY
# define open _open
# define read _read
# define write _write
# define close _close
#endif

#ifdef NO_DEFLATE /* for compatibility with old definition */
# define NO_GZCOMPRESS
#endif

#if defined(STDC99) || (defined(__TURBOC__) && __TURBOC__ >= 0x550)
# ifndef HAVE_VSNPRINTF
# define HAVE_VSNPRINTF
# endif
#endif

#if defined(__CYGWIN__)
# ifndef HAVE_VSNPRINTF
# define HAVE_VSNPRINTF
# endif
#endif

#if defined(MSDOS) && defined(__BORLANDC__) && (BORLANDC > 0x410)
# ifndef HAVE_VSNPRINTF
# define HAVE_VSNPRINTF
# endif
#endif

#ifndef HAVE_VSNPRINTF
# ifdef MSDOS
/* vsnprintf may exist on some MS-DOS compilers (DJGPP?),
 but for now we just assume it doesn't. */
# define NO_vsnprintf
# endif
# ifdef __TURBOC__
# define NO_vsnprintf
# endif
# ifdef WIN32
/* In Win32, vsnprintf is available as the "non-ANSI" _vsnprintf. */
# if !defined(vsnprintf) && !defined(NO_vsnprintf)
# if !defined(_MSC_VER) || ( defined(_MSC_VER) && _MSC_VER < 1500 )
# define vsnprintf _vsnprintf
# endif
# endif
# endif
# ifdef __SASC
# define NO_vsnprintf
# endif
# ifdef VMS
# define NO_vsnprintf
# endif
# ifdef __OS400__
# define NO_vsnprintf
# endif
# ifdef __MVS__
# define NO_vsnprintf
# endif
#endif

/* unlike snprintf (which is required in C99, yet still not supported by
 Microsoft more than a decade later!), _snprintf does not guarantee null
 termination of the result -- however this is only used in gzlib.c where
 the result is assured to fit in the space provided */
#ifdef _MSC_VER
# define snprintf _snprintf
#endif

#ifndef local
# define local static
#endif
/* compile with -Dlocal if your debugger can't find static symbols */

/* gz* functions always use library allocation functions */
#ifndef STDC
 extern voidp malloc OF((uInt size));
 extern void free OF((voidpf ptr));
#endif

/* get errno and strerror definition */
#if defined UNDER_CE
# include <windows.h>
# define zstrerror() gz_strwinerror((DWORD)GetLastError())
#else
# ifndef NO_STRERROR
# include <errno.h>
# define zstrerror() strerror(errno)
# else
# define zstrerror() "stdio error (consult errno)"
# endif
#endif

/* provide prototypes for these when building zlib without LFS */
#if !defined(_LARGEFILE64_SOURCE) || _LFS64_LARGEFILE-0 == 0
 ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
 ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
 ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
 ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
#endif

/* default memLevel */
#if MAX_MEM_LEVEL >= 8
# define DEF_MEM_LEVEL 8
#else
# define DEF_MEM_LEVEL MAX_MEM_LEVEL
#endif

/* default i/o buffer size -- double this for output when reading (this and
 twice this must be able to fit in an unsigned type) */
#define GZBUFSIZE 8192

/* gzip modes, also provide a little integrity check on the passed structure */
#define GZ_NONE 0
#define GZ_READ 7247
#define GZ_WRITE 31153
#define GZ_APPEND 1 /* mode set to GZ_WRITE after the file is opened */

/* values for gz_state how */
#define LOOK 0 /* look for a gzip header */
#define COPY 1 /* copy input directly */
#define GZIP 2 /* decompress a gzip stream */

/* internal gzip file state data structure */
typedef struct {
 /* exposed contents for gzgetc() macro */
 struct gzFile_s x; /* "x" for exposed */
 /* x.have: number of bytes available at x.next */
 /* x.next: next output data to deliver or write */
 /* x.pos: current position in uncompressed data */
 /* used for both reading and writing */
 int mode; /* see gzip modes above */
 int fd; /* file descriptor */
 char *path; /* path or fd for error messages */
 unsigned size; /* buffer size, zero if not allocated yet */
 unsigned want; /* requested buffer size, default is GZBUFSIZE */
 unsigned char *in; /* input buffer */
 unsigned char *out; /* output buffer (double-sized when reading) */
 int direct; /* 0 if processing gzip, 1 if transparent */
 /* just for reading */
 int how; /* 0: get header, 1: copy, 2: decompress */
 z_off64_t start; /* where the gzip data started, for rewinding */
 int eof; /* true if end of input file reached */
 int past; /* true if read requested past end */
 /* just for writing */
 int level; /* compression level */
 int strategy; /* compression strategy */
 /* seek request */
 z_off64_t skip; /* amount to skip (already rewound if backwards) */
 int seek; /* true if seek request pending */
 /* error information */
 int err; /* error code */
 char *msg; /* error message */
 /* zlib inflate or deflate stream */
 z_stream strm; /* stream structure in-place (not a pointer) */
} gz_state;
typedef gz_state FAR *gz_statep;

/* shared functions */
void ZLIB_INTERNAL gz_error OF((gz_statep, int, const char *));
#if defined UNDER_CE
char ZLIB_INTERNAL *gz_strwinerror OF((DWORD error));
#endif

/* GT_OFF(x), where x is an unsigned value, is true if x > maximum z_off64_t
 value -- needed when comparing unsigned to z_off64_t, which is signed
 (possible z_off64_t types off_t, off64_t, and long are all signed) */
#ifdef INT_MAX
# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > INT_MAX)
#else
unsigned ZLIB_INTERNAL gz_intmax OF((void));
# define GT_OFF(x) (sizeof(int) == sizeof(z_off64_t) && (x) > gz_intmax())
#endif