compress.h

和Unix的compress/uncompress兼容的压缩/解压算法16位程序

/* does your system use far pointers ? if you want it enabled keep this */
/* if you have segment limit and compile in larger than 13 bits         */
/* then you will have to use compact or large model if your compiler    */
/* does not support far pointer keyword.                                */

#ifndef FAR
#define FAR
#endif

/* What type does the alloc() function return, char or void? */

#ifndef ALLOCTYPE
#define ALLOCTYPE char
#endif

/* If you use compusi.dos and your computer supports the unix */
/* file links and the link code is set properly in the stat() */
/* then define the following:                                 */
/* #define USE_LINKS */

/* Does your run time library support the ANSI functions for:*/

/* reverse string set search?  strrpbrk() if so:             */
/*#define NO_REVSEARCH*//* dos module uses this function. */

/* Does your library include strrchr()? If not define this:  */
/*#define NO_STRRCHR*//* unix/xenix module uses this function*/

/* Does your library include strchr()? If not define this:   */
/*#define NO_STRCHR*//* dos module uses this function.       */

/* definition for const key word if supported */
#ifndef CONST
#define CONST
#endif


/*  And now for some typedefs */
typedef unsigned short CODE;
typedef unsigned char UCHAR;
typedef unsigned int  INTCODE;
typedef unsigned int HASH;
typedef int FLAG;

  /* 
   * You can define the value of MAXBITS to be anything betweeen MINBITS
   * and MAXMAXBITS.  This is will determine the maximum memory you will
   * use and how the tables will be handled.  I recommend you just leave
   * it at MAXMAXBITS, because you can define DFLTBITS in compiling the
   * module COMPRESS.C to set the default, and you can vary the number
   * of bits at runtime by using the -b switch.
   */

   /*
   * The only reason to change MAXBITS is if you absolutely must have
   * faster performance. If you specify 14 bits, the tables will not
   * be split; at 13 bits, you can fit in the MSDOS small memory model
   * and allocate tables in near heap.
   * This value is available to other modules through the variable maxbits.
   */

#define INITBITS    9
#define MINBITS     12
#define MAXMAXBITS  16

#ifndef MAXBITS
#define MAXBITS    MAXMAXBITS
#endif

#if (MAXBITS > MAXMAXBITS)
#undef MAXBITS
#define MAXBITS    MAXMAXBITS
#endif

#if (MAXBITS < MINBITS)
#undef MAXBITS
#define MAXBITS  MINBITS
#endif

  /* You should define DFLTBITS to be the default compression code
   * bit length you desire on your system.
   * (I define mine in the compiler command line in my Makefile.LvR)
   * (I leave mine alone and keep to the maximum. DjG)
   */

#ifndef DFLTBITS
#define DFLTBITS MAXBITS
#endif
#if (DFLTBITS < MINBITS)
#undef DFLTBITS
#define DFLTBITS MINBITS
#endif
#if (DFLTBITS > MAXBITS)
#undef DFLTBITS
#define DFLTBITS MAXBITS
#endif

/* THIS IS TO COMPILE A 13 BIT MODEL IN SMALL MEMORY AND NEAR HEAP */
/* AS SET UP IT WILL WORK WITH MICROSOFT C COMPILER                */

#if (MAXBITS < 14)
#ifdef SMALLMODEL
#define NEARHEAP TRUE
#undef FAR
#define FAR
#endif
#endif

/* correcting for different types of pointer arithmatic */
/* probably won't have to change it                     */
#define NULLPTR(type)   ((type FAR *) NULL)


/* in making this program portable the following allocation and          */
/* free functions are called, with the following parameters:             */
/*        ALLOCTYPE FAR *emalloc(unsigned int x, int y)                  */
/*                 void  efree(ALLOCTYPE FAR *ptr)                       */
/* you must define the allocation function and the free function         */
/* keep in mind that the casts must be correct for your compiler         */
/* NOTE these are the two functions to change for allocating pointers to */
/* far data space if you are not using Microsoft C v.5.1                 */
/* Consult your compiler manual and find the low level function that     */
/* returns a far pointer when compiled in the small model.               */
/* if your compiler does not support that, you will have to compile with */
/* a model that defaults to far pointers to data (compact or large model)*/
/* HERE ARE SOME SAMPLE PREDEFINED ONES                                  */

#ifdef MSC
#include <malloc.h>
#ifdef NEARHEAP
#define ALLOCATE(x,y)   malloc((size_t)((x)*(y)))
#define FREEIT(ptr)     free((ptr))
#else
#define ALLOCATE(x,y)   _fmalloc((size_t)((x)*(y)))
#define FREEIT(ptr)     _ffree((ptr))
#endif
#endif

#ifdef HUGE
#include <malloc.h>
#define ALLOCATE(x,y)   halloc((long)(x),(size_t)(y))
#define FREEIT(ptr)     hfree(ptr)
#endif

#ifdef __TURBOC__
#include <alloc.h>
#ifdef NEARHEAP
#define ALLOCATE(x,y)  malloc((unsigned int)((x)*(y)))
#define FREEIT(x)      free(x)
#else
#define ALLOCATE(x,y)  farmalloc((unsigned long)((x)*(y)))
#define FREEIT(x)    farfree(x)
#endif
#endif

/* default allocation function, in segmented addressing, must return */
/* a far pointer or compile with far pointer data as default         */
#ifndef ALLOCATE
#include <malloc.h>
#define ALLOCATE(x,y)   malloc((unsigned int)x*y)
#define FREEIT(ptr)     free((ptr))
#endif


# ifdef MAXSEG_64K
#   if  MAXBITS > 14
#       define SPLIT_HT   TRUE
#   else
#       define SPLIT_HT   0
#   endif
# else
#   define SPLIT_HT   0
# endif

# ifdef MAXSEG_64K
#   if  MAXBITS > 15
#       define SPLIT_PFX   TRUE
#   else
#       define SPLIT_PFX   0
#   endif
# else
#   define SPLIT_PFX   0
# endif

#ifndef BUFSIZ
#define BUFSIZ 512
#endif

#ifdef NO_SETBUF
#define NO_SETVBUF
#endif

#ifdef NO_SETVBUF
#   ifndef NO_SETBUF
#       define setvbuf(fp,buf,mode,size) setbuf((fp),(buf))
#       define ZBUFSIZE BUFSIZ
#       define XBUFSIZE BUFSIZ
#   else
#       define setvbuf(fp,buf,mode,size)
#       define ZBUFSIZE (1)
#       define XBUFSIZE (1)
#   endif
#else
#   ifdef NEARHEAP
#       define XBUFSIZE    (0xC00)
#       define ZBUFSIZE    (0x1800)
#   else
#       define XBUFSIZE    (0x3000)      /* 12k bytes */
#       define ZBUFSIZE    (0x6000)      /* 24k bytes */
#   endif
#endif

#define UNUSED      ((CODE)0)   /* Indicates hash table value unused    */
#define CLEAR       ((CODE)256) /* Code requesting table to be cleared  */
#define FIRSTFREE   ((CODE)257) /* First free code for token encoding */
#define MAXTOKLEN   512         /* Max chars in token; size of buffer   */
#define OK          0           /* Result codes from functions:         */

#ifdef vms
#define ERROR       0x10000004  /* General unspecified error            */
#define NORMAL      1           /* No error                             */
#define unlink(x)   remove(x)
#else
#    define NORMAL      0
#    ifdef ERROR
#        if (ERROR == NORMAL)
#            define ERROR   1   /* force redefine if (ERROR == NORMAL)  */
#        endif
#    else
#        define ERROR       1
#    endif
#endif

#define SIGNAL_ERROR -1         /*   signal function error              */
#define NOMEM       2           /*   Ran out of memory                  */
#define TOKTOOBIG   3           /*   Token longer than MAXTOKLEN chars  */
#define READERR     4           /*   I/O error on input                 */
#define WRITEERR    5           /*   I/O error on output                */
#define INFILEBAD   6           /*   Infile not in compressed format    */
#define CODEBAD     7           /*   Infile contained a bad token code  */
#define TABLEBAD    8           /*   The tables got corrupted (!)       */
#define NOSAVING    9           /*   no saving in file size             */
#define NOTOPENED  10           /*   output file couldn't be opened     */
#define YES         1
#define NO          0


#include "compress.fns"

/* defines opening mode for files */
/* and suffixes for compressed file */

#ifdef MSDOS
#define WRITE_FILE_TYPE "wb"
#define READ_FILE_TYPE "rb"
#define SUFFIX "Z"
#else
#ifdef vms
#define SUFFIX "_Z"
#define WRITE_FILE_TYPE "wb"
#define READ_FILE_TYPE "rb"
#else
#define WRITE_FILE_TYPE "w"
#define READ_FILE_TYPE "r"
#define SUFFIX ".Z"
#endif
#endif

/* The VERBOSE flag defines the default value of the verbose variable */
/* If it's not already defined, we set it to FALSE here since most */
/* systems set the default that way.  -Dal */
#ifndef VERBOSE
#define VERBOSE FALSE
#endif

/* Defines for third byte of header */
#define BIT_MASK    0x1f
#define BLOCK_MASK  0x80
/* Masks 0x40 and 0x20 are free.  I think 0x20 should mean that there is
   a fourth header byte (for expansion).
*/


#define CHECK_GAP 10000L     /* ratio check interval */

#ifdef MAIN
UCHAR magic_header[] = { 0x1F,0x9D };  /* 1F 9D */

char rcs_ident[] = TITLE;

#ifdef MWC
long _stksize = 20000L;     /* set MWC's stack to 20,000 */
#ifdef MWC_NAME           /* if defined in makefile set _cmdname for */
char _cmdname[]=MWC_NAME;   /* compress,zcat,uncomp check for desktop and */
#endif                      /* dumb shells */
#endif

#ifdef SOZOBON
long _STKSIZ = 20000L;      /* set runtime stack to 20,000 bytes */
#ifndef CMDNAME
#define CMDNAME "compress"
#endif
#endif

int overwrite = 0;          /* Do not overwrite unless given -f flag */
int maxbits = DFLTBITS;     /* user settable max # bits/code */

int exit_stat = 0;
int keep = KEEPFLAG;            /* True = don't kill file */
int keep_error = FALSE;     /* True = keep output file even if error exist */
char *prog_name;
char ifname[_MAX_DIR];
char inpath[_MAX_DIR];
char ofname [_MAX_DIR];
char outpath[_MAX_DIR];
int is_list = FALSE;            /* flag for file parameters */
char endchar[1];
char xbuf[XBUFSIZE];
char zbuf[ZBUFSIZE];
#ifdef MSDOS
char separator[] = "\\";
#else
char separator[] = "/";
#endif
int nomagic = FALSE;  /* Use a 3-byte magic number header, unless old file */
int zcat_flg = FALSE; /* Write output on stdout, suppress messages */
int quiet = !VERBOSE; /* don't tell me about compression */
/*
 * block compression parameters -- after all codes are used up,
 * and compression rate changes, start over.
 */
int block_compress = BLOCK_MASK;
#ifdef COMP40
long int ratio = 0L;
long checkpoint = CHECK_GAP;
#endif

/* force the overwrite */
int force = 0;

#ifdef DEBUG
int verbose = VERBOSE;
int debug = FALSE;
#endif /* DEBUG */

#ifndef NOSIGNAL
SIGTYPE (*bgnd_flag)();
#endif

int do_decomp = FALSE;

#else               /* not defining instance */

extern UCHAR magic_header[];
extern char rcs_ident[];
#ifdef MWC
extern long _stksize;
#endif
extern int overwrite;
extern int maxbits;


extern int exit_stat;
extern int keep;
extern int keep_error;
extern char *prog_name;
extern char inpath[];
extern char outpath[];
extern int is_list;
extern char endchar[];
extern char xbuf[];
extern char zbuf[];
extern char ifname[];
extern char ofname[];
extern char separator[];
extern int nomagic;
extern int zcat_flg;
extern int quiet;
extern int block_compress;
#ifdef COMP40
extern long int ratio;
extern long checkpoint;
#endif
extern int force;

#ifdef DEBUG
extern int verbose;
extern int debug;
#endif /* DEBUG */

#ifndef NOSIGNAL
extern SIGTYPE (*bgnd_flag)();
#endif
extern int do_decomp;
#endif