/*******************************************************************************                                                                             **       Copyright (C) 1992-1995 Tony Robinson                                 **                                                                             **       See the file LICENSE for conditions on distribution and usage         **                                                                             *******************************************************************************//* * $Id: vario.c,v 1.3 2002/01/28 01:16:52 jason Exp $ */#include <math.h>#include <stdio.h>#include <stdlib.h>#include "shorten.h"#ifdef HAVE_CONFIG_H#include "config.h"#endifextern char *argv0;extern int ReadingFunctionCode;extern ulong SHNFilePosition;extern ushort SHNBitPosition;extern ulong SHNGBuffer;extern ulong LastBufferReadPosition;extern ulong SHNLastBufferReadPosition;extern ushort SHNByteGet;extern ushort SHNBufferOffset;#define MASKTABSIZE 33ulong masktab[MASKTABSIZE];void mkmasktab() {  int i;  ulong val = 0;  masktab[0] = val;  for(i = 1; i < MASKTABSIZE; i++) {    val <<= 1;    val |= 1;    masktab[i] = val;  }}static uchar *putbuf;static uchar *putbufp;static ulong  pbuffer;static int    nbitput;void var_put_init() {  mkmasktab();  putbuf   = (uchar*) pmalloc((ulong) BUFSIZ);  putbufp  = putbuf;  pbuffer  = 0;  nbitput  = 0;}static uchar *getbuf;static uchar *getbufp;static int    nbyteget;static ulong  gbuffer;static int    nbitget;void var_get_init() {  mkmasktab();  getbuf   = (uchar*) pmalloc((ulong) BUFSIZ);  getbufp  = getbuf;  nbyteget = 0;  gbuffer  = 0;  nbitget  = 0;}void word_put(buffer, stream) ulong buffer; FILE *stream; {  *putbufp++ = buffer >> 24;  *putbufp++ = buffer >> 16;  *putbufp++ = buffer >>  8;  *putbufp++ = buffer;  if(putbufp - putbuf == BUFSIZ) {    if(fwrite((char*) putbuf, 1, BUFSIZ, stream) != BUFSIZ)      update_exit(1, "failed to write compressed stream\n");    putbufp = putbuf;  }}void uvar_put(val, nbin, stream) ulong val; int nbin; FILE *stream; {  ulong lobin, nsd;  int  i, nlobin;  if(nbin >= MASKTABSIZE)    update_exit(1, "overflow of masktab[%d]\n", MASKTABSIZE);  lobin = (1L << nbin) | (val & masktab[nbin]);  nsd = val >> nbin;  nlobin = nbin + 1;  if(nbitput + nsd >= 32) {    for(i = 0; i < ((nbitput + nsd) >> 5); i++) {      word_put(pbuffer, stream);      pbuffer = 0;    }    nbitput = (nbitput + nsd) % 32;  }  else    nbitput += nsd;  while(nlobin != 0) {    if(nbitput + nlobin >= 32) {      pbuffer |= (lobin >> (nbitput + nlobin - 32));      word_put(pbuffer, stream);      pbuffer = 0;      nlobin -= 32 - nbitput;      nbitput = 0;    }    else {      nbitput += nlobin;      pbuffer |= (lobin << (32 - nbitput));      nlobin = 0;    }  }}void ulong_put(val, stream) ulong val; FILE *stream; {  int i, nbit;  for(i = 31; i >= 0 && (val & (1L << i)) == 0; i--);  nbit = i + 1;  uvar_put((ulong) nbit, ULONGSIZE, stream);  uvar_put(val & masktab[nbit], nbit, stream);}ulong word_get(FILE *stream){  ulong buffer;  if(nbyteget < 4)  {    int bytes;/*    LastBufferReadPosition = (ulong)ftell(stream); */    LastBufferReadPosition = bytes_read;    bytes = fread((char*) getbuf, 1, BUFSIZ, stream);    nbyteget += bytes;    if(nbyteget < 4)      update_exit(1, "premature EOF on compressed stream\n");    bytes_read += bytes;    getbufp = getbuf;  }  buffer = (((slong) getbufp[0]) << 24) | (((slong) getbufp[1]) << 16) |    (((slong) getbufp[2]) <<  8) | ((slong) getbufp[3]);  getbufp += 4;  nbyteget -= 4;  return(buffer);}slong uvar_get(nbin, stream) int nbin; FILE *stream;{  slong result;  if(ReadingFunctionCode == TRUE)  {    SHNLastBufferReadPosition = (ulong)  LastBufferReadPosition;    SHNFilePosition           = (ulong)  ftell(stream);    SHNBitPosition            = (ushort) nbitget;    SHNGBuffer                = (ulong)  gbuffer;    SHNByteGet                = (ushort) nbyteget;    SHNBufferOffset           = (ushort) (getbufp-getbuf);  }  if(nbitget == 0)  {    gbuffer = word_get(stream);    nbitget = 32;  }  for(result = 0; !(gbuffer & (1L << --nbitget)); result++)  {    if(nbitget == 0)    {      gbuffer = word_get(stream);      nbitget = 32;    }  }  while(nbin != 0)  {    if(nbitget >= nbin)    {      result = (result << nbin) | ((gbuffer >> (nbitget-nbin)) &masktab[nbin]);      nbitget -= nbin;      nbin = 0;    }    else    {      result = (result << nbitget) | (gbuffer & masktab[nbitget]);      gbuffer = word_get(stream);      nbin -= nbitget;      nbitget = 32;    }  }  return(result);}ulong ulong_get(stream) FILE *stream; {  unsigned int nbit = uvar_get(ULONGSIZE, stream);  return(uvar_get(nbit, stream));}void var_put(val, nbin, stream) slong val; int nbin; FILE *stream; {  if(val < 0) uvar_put((ulong) ((~val) << 1) | 1L, nbin + 1, stream);  else uvar_put((ulong) ((val) << 1), nbin + 1, stream);}void var_put_quit(stream) FILE *stream; {  /* flush to a word boundary */  uvar_put((ulong) 0, 31, stream);  /* and write out the remaining chunk in the buffer */  if(fwrite((char*) putbuf, 1, putbufp - putbuf, stream) != putbufp - putbuf)    update_exit(1, "failed to write compressed stream\n");  free((char*) putbuf);}slong var_get(nbin, stream) int nbin; FILE *stream; {  ulong uvar = (ulong) uvar_get(nbin + 1, stream);  if(uvar & 1) return((slong) ~(uvar >> 1));  else return((slong) (uvar >> 1));}void var_get_quit() {  free((char*) getbuf);}int sizeof_uvar(val, nbin) ulong val; int nbin; {  return((val >> nbin) + nbin);}int sizeof_var(val, nbin) slong val; int nbin; {  return((labs(val) >> nbin) + nbin + 1);}