msdos.c

给出了 zip 压缩算法的完整实现过程。

    }
    ziperr(ZE_MEM, "zcfree: ptr not found");
}
#endif /* __TURBOC__ */

#if defined(MSC) || defined(__WATCOMC__)
#if (!defined(_MSC_VER) || (_MSC_VER < 700))
#  define _halloc  halloc
#  define _hfree   hfree
#endif

zvoid far *zcalloc (unsigned items, unsigned size)
{
    return (zvoid far *)_halloc((long)items, size);
}

zvoid zcfree (zvoid far *ptr)
{
    _hfree((void huge *)ptr);
}
#endif /* MSC || __WATCOMC__ */

#endif /* MY_ZCALLOC */

#if (defined(__WATCOMC__) && defined(ASMV) && !defined(__386__))
/* This is a hack to connect "call _exit" in match.asm to exit() */
#pragma aux xit "_exit" parm caller []
void xit(void)
{
    exit(20);
}
#endif

#endif /* !UTIL */

local int is_running_on_windows(void)
{
    char * var = getenv("OS");

    /* if the OS env.var says 'Windows_NT' then */
    /* we're likely running on a variant of WinNT */
    if ((NULL != var) && (0 == strcmp("Windows_NT", var)))
    {
        return 1;
    }

    /* if the windir env.var is non-null then */
    /* we're likely running on a variant of Win9x */
    /* DOS mode of Win9x doesn't define windir, only winbootdir */
    /* NT's command.com can't see lowercase env. vars */
    var = getenv("windir");
    if ((NULL != var) && (0 != var[0]))
    {
        return 1;
    }

    return 0;
}

void check_for_windows(const char *app)
{
    /* Print a warning for users running under Windows */
    /* to reduce bug reports due to running DOS version */
    /* under Windows, when Windows version usually works correctly */
    if (is_running_on_windows())
    {
        printf("\nzip warning:  You are running MSDOS %s on Windows.\n"
               "Try the Windows version before reporting any problems.\n",
               app);
    }
}

#ifndef WINDLL
/******************************/
/*  Function version_local()  */
/******************************/

static ZCONST char CompiledWith[] = "Compiled with %s%s for %s%s%s.\n\n";
                        /* At module level to keep Turbo C++ 1.0 happy !! */

void version_local()
{
#if defined(__DJGPP__) || defined(__WATCOMC__) || \
    (defined(_MSC_VER) && (_MSC_VER != 800))
    char buf[80];
#endif

/* Define the compiler name and version strings */
#if defined(__GNUC__)
#  if defined(__DJGPP__)
    sprintf(buf, "djgpp v%d.%02d / gcc ", __DJGPP__, __DJGPP_MINOR__);
#    define COMPILER_NAME1      buf
#  elif defined(__GO32__)         /* __GO32__ is defined as "1" only (sigh) */
#    define COMPILER_NAME1      "djgpp v1.x / gcc "
#  elif defined(__EMX__)          /* ...so is __EMX__ (double sigh) */
#    define COMPILER_NAME1      "emx+gcc "
#  else
#    define COMPILER_NAME1      "gcc "
#  endif
#  define COMPILER_NAME2        __VERSION__
#elif defined(__WATCOMC__)
#  if (__WATCOMC__ % 10 > 0)
/* We do this silly test because __WATCOMC__ gives two digits for the  */
/* minor version, but Watcom packaging prefers to show only one digit. */
    sprintf(buf, "Watcom C/C++ %d.%02d", __WATCOMC__ / 100,
            __WATCOMC__ % 100);
#  else
    sprintf(buf, "Watcom C/C++ %d.%d", __WATCOMC__ / 100,
            (__WATCOMC__ % 100) / 10);
#  endif
#  define COMPILER_NAME1        buf
#  define COMPILER_NAME2        ""
#elif defined(__TURBOC__)
#  ifdef __BORLANDC__
#    define COMPILER_NAME1      "Borland C++"
#    if (__BORLANDC__ < 0x0200)
#      define COMPILER_NAME2    " 1.0"
#    elif (__BORLANDC__ == 0x0200)   /* James:  __TURBOC__ = 0x0297 */
#      define COMPILER_NAME2    " 2.0"
#    elif (__BORLANDC__ == 0x0400)
#      define COMPILER_NAME2    " 3.0"
#    elif (__BORLANDC__ == 0x0410)   /* __BCPLUSPLUS__ = 0x0310 */
#      define COMPILER_NAME2    " 3.1"
#    elif (__BORLANDC__ == 0x0452)   /* __BCPLUSPLUS__ = 0x0320 */
#      define COMPILER_NAME2    " 4.0 or 4.02"
#    elif (__BORLANDC__ == 0x0460)   /* __BCPLUSPLUS__ = 0x0340 */
#      define COMPILER_NAME2    " 4.5"
#    elif (__BORLANDC__ == 0x0500)   /* __TURBOC__ = 0x0500 */
#      define COMPILER_NAME2    " 5.0"
#    else
#      define COMPILER_NAME2    " later than 5.0"
#    endif
#  else
#    define COMPILER_NAME1      "Turbo C"
#    if (__TURBOC__ > 0x0401)
#      define COMPILER_NAME2    "++ later than 3.0"
#    elif (__TURBOC__ == 0x0401)     /* Kevin:  3.0 -> 0x0401 */
#      define COMPILER_NAME2    "++ 3.0"
#    elif (__TURBOC__ == 0x0296)     /* [662] checked by SPC */
#      define COMPILER_NAME2    "++ 1.01"
#    elif (__TURBOC__ == 0x0295)     /* [661] vfy'd by Kevin */
#      define COMPILER_NAME2    "++ 1.0"
#    elif (__TURBOC__ == 0x0201)     /* Brian:  2.01 -> 0x0201 */
#      define COMPILER_NAME2    " 2.01"
#    elif ((__TURBOC__ >= 0x018d) && (__TURBOC__ <= 0x0200)) /* James: 0x0200 */
#      define COMPILER_NAME2    " 2.0"
#    elif (__TURBOC__ > 0x0100)
#      define COMPILER_NAME2    " 1.5"          /* James:  0x0105? */
#    else
#      define COMPILER_NAME2    " 1.0"          /* James:  0x0100 */
#    endif
#  endif
#elif defined(MSC)
#  if defined(_QC) && !defined(_MSC_VER)
#    define COMPILER_NAME1      "Microsoft Quick C"
#    define COMPILER_NAME2      ""      /* _QC is defined as 1 */
#  else
#    define COMPILER_NAME1      "Microsoft C "
#    ifdef _MSC_VER
#      if (_MSC_VER == 800)
#        define COMPILER_NAME2  "8.0/8.0c (Visual C++ 1.0/1.5)"
#      else
#        define COMPILER_NAME2 \
           (sprintf(buf, "%d.%02d", _MSC_VER/100, _MSC_VER%100), buf)
#      endif
#    else
#      define COMPILER_NAME2    "5.1 or earlier"
#    endif
#  endif
#else
#    define COMPILER_NAME1      "unknown compiler"
#    define COMPILER_NAME2      ""
#endif

/* Define the OS name and memory environment strings */
#if defined(__WATCOMC__) || defined(__TURBOC__) || defined(MSC) || \
    defined(__GNUC__)
#  define OS_NAME1      "\nMS-DOS"
#else
#  define OS_NAME1      "MS-DOS"
#endif

#if (defined(__GNUC__) || (defined(__WATCOMC__) && defined(__386__)))
#  define OS_NAME2      " (32-bit)"
#elif defined(M_I86HM) || defined(__HUGE__)
#  define OS_NAME2      " (16-bit, huge)"
#elif defined(M_I86LM) || defined(__LARGE__)
#  define OS_NAME2      " (16-bit, large)"
#elif defined(M_I86MM) || defined(__MEDIUM__)
#  define OS_NAME2      " (16-bit, medium)"
#elif defined(M_I86CM) || defined(__COMPACT__)
#  define OS_NAME2      " (16-bit, compact)"
#elif defined(M_I86SM) || defined(__SMALL__)
#  define OS_NAME2      " (16-bit, small)"
#elif defined(M_I86TM) || defined(__TINY__)
#  define OS_NAME2      " (16-bit, tiny)"
#else
#  define OS_NAME2      " (16-bit)"
#endif

/* Define the compile date string */
#ifdef __DATE__
#  define COMPILE_DATE " on " __DATE__
#else
#  define COMPILE_DATE ""
#endif

    printf(CompiledWith, COMPILER_NAME1, COMPILER_NAME2,
           OS_NAME1, OS_NAME2, COMPILE_DATE);

} /* end function version_local() */
#endif /* !WINDLL */


#if 0 /* inserted here for future use (clearing of archive bits) */
#if (defined(__GO32__) && (!defined(__DJGPP__) || (__DJGPP__ < 2)))

#include <errno.h>
int volatile _doserrno;

unsigned _dos_setfileattr(char *name, unsigned attr)
{
#if 0   /* stripping of trailing '/' is not needed for zip-internal use */
    unsigned namlen = strlen(name);
    char *i_name = alloca(namlen + 1);

    strcpy(i_name, name);
    if (namlen > 1 && i_name[namlen-1] == '/' && i_name[namlen-2] != ':')
        i_name[namlen-1] = '\0';
    asm("movl %0, %%edx": : "g" (i_name));
#else
    asm("movl %0, %%edx": : "g" (name));
#endif
    asm("movl %0, %%ecx": : "g" (attr));
    asm("movl $0x4301, %eax");
    asm("int $0x21": : : "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi");
    _doserrno = 0;
    asm("jnc 1f");
    asm("movl %%eax, %0": "=m" (_doserrno));
    switch (_doserrno) {
    case 2:
    case 3:
           errno = ENOENT;
           break;
    case 5:
           errno = EACCES;
           break;
    }
    asm("1:");
    return (unsigned)_doserrno;
}

#endif /* DJGPP v1.x */
#endif /* never (not yet used) */


#if (defined(__DJGPP__) && (__DJGPP__ >= 2))

/* Disable determination of "x" bit in st_mode field for [f]stat() calls. */
int _is_executable (const char *path, int fhandle, const char *ext)
{
    return 0;
}

/* Prevent globbing of filenames.  This gives the same functionality as
 * "stubedit <program> globbing=no" did with DJGPP v1.
 */
#ifndef USE_DJGPP_GLOB
char **__crt0_glob_function(char *_arg)
{
    return NULL;
}
#endif

/* Reduce the size of the executable and remove the functionality to read
 * the program's environment from whatever $DJGPP points to.
 */
#if !defined(USE_DJGPP_ENV) || defined(UTIL)
void __crt0_load_environment_file(char *_app_name)
{
}
#endif

#endif /* __DJGPP__ >= 2 */


#if defined(_MSC_VER) && _MSC_VER == 700

/*
 * ARGH.  MSC 7.0 libraries think times are based on 1899 Dec 31 00:00, not
 *  1970 Jan 1 00:00.  So we have to diddle time_t's appropriately:  add
 *  70 years' worth of seconds for localtime() wrapper function;
 *  (70*365 regular days + 17 leap days + 1 1899 day) * 86400 ==
 *  (25550 + 17 + 1) * 86400 == 2209075200 seconds.
 *  Let time() and stat() return seconds since 1970 by using our own
 *  _dtoxtime() which is the routine that is called by these two functions.
 */


#ifdef UTIL
#  include <time.h>
#endif

#ifndef UTIL
#undef localtime
struct tm *localtime(const time_t *);

struct tm *msc7_localtime(const time_t *clock)
{
   time_t t = *clock;

   t += 2209075200L;
   return localtime(&t);
}
#endif /* !UTIL */


void __tzset(void);
int _isindst(struct tm *);

extern int _days[];

/* Nonzero if `y' is a leap year, else zero. */
#define leap(y) (((y) % 4 == 0 && (y) % 100 != 0) || (y) % 400 == 0)

/* Number of leap years from 1970 to `y' (not including `y' itself). */
#define nleap(y) (((y) - 1969) / 4 - ((y) - 1901) / 100 + ((y) - 1601) / 400)

time_t _dtoxtime(year, month, mday, hour, min, sec)
int year, month, mday, year, hour, min, sec;
{
   struct tm tm;
   time_t t;
   int days;

   days = _days[month - 1] + mday;
   year += 1980;
   if (leap(year) && month > 2)
     ++days;
   tm.tm_yday = days;
   tm.tm_mon = month - 1;
   tm.tm_year = year - 1900;
   tm.tm_hour = hour;
   __tzset();
   days += 365 * (year - 1970) + nleap (year);
   t = 86400L * days + 3600L * hour + 60 * min + sec + _timezone;
   if (_daylight && _isindst(&tm))
      t -= 3600;
   return t;
}

#endif /* _MSC_VER && _MSC_VER == 700 */


#ifdef __WATCOMC__

/* This papers over a bug in Watcom 10.6's standard library... sigh */
/* Apparently it applies to both the DOS and Win32 stat()s.         */

int stat_bandaid(const char *path, struct stat *buf)
{
  char newname[4];
  if (!stat(path, buf))
    return 0;
  else if (!strcmp(path, ".") || (path[0] && !strcmp(path + 1, ":."))) {
    strcpy(newname, path);
    newname[strlen(path) - 1] = '\\';   /* stat(".") fails for root! */
    return stat(newname, buf);
  } else
    return -1;
}

#endif