ENH: Initial import

1 files changed, 545 insertions, 0 deletions

diff --git a/Utilities/cmcompress/cmcompress.c b/Utilities/cmcompress/cmcompress.c
new file mode 100644
index 0000000..6ac4956
--- /dev/null
+++ b/Utilities/cmcompress/cmcompress.c
@@ -0,0 +1,545 @@
+/*
+ * Copyright (c) 1985, 1986 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * James A. Woods, derived from original work by Spencer Thomas
+ * and Joseph Orost.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *  This product includes software developed by the University of
+ *  California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "cmcompress.h"
+
+#include <errno.h>
+#include <string.h>
+
+static const char_type magic_header[] = { "\037\235" };  /* 1F 9D */
+
+/* Defines for third byte of header */
+#define BIT_MASK  0x1f
+#define BLOCK_MASK  0x80
+#define CHECK_GAP 10000  /* ratio check interval */
+/* Masks 0x40 and 0x20 are free.  I think 0x20 should mean that there is
+   a fourth header byte (for expansion).
+   */
+#define INIT_BITS 9      /* initial number of bits/code */
+
+#ifdef COMPATIBLE    /* But wrong! */
+# define MAXCODE(n_bits)  (1 << (n_bits) - 1)
+#else
+# define MAXCODE(n_bits)  ((1 << (n_bits)) - 1)
+#endif /* COMPATIBLE */
+
+#define htabof(i)  cdata->htab[i]
+#define codetabof(i)  cdata->codetab[i]
+
+/*
+ * the next two codes should not be changed lightly, as they must not
+ * lie within the contiguous general code space.
+ */
+#define FIRST  257  /* first free entry */
+#define  CLEAR  256  /* table clear output code */
+
+static void cl_hash(struct cmcompress_stream* cdata, count_int hsize);    /* reset code table */
+static void cl_block (struct cmcompress_stream* cdata);    /* table clear for block compress */
+static void prratio( FILE *stream, long int num, long int den);
+static void output(struct cmcompress_stream* cdata, code_int  code);
+static void writeerr();
+
+int cmcompress_compress_initialize(struct cmcompress_stream* cdata)
+{
+  cdata->maxbits = BITS;      /* user settable max # bits/code */
+  cdata->maxmaxcode = 1 << BITS;  /* should NEVER generate this code */
+  cdata->hsize = HSIZE;      /* for dynamic table sizing */
+  cdata->free_ent = 0;      /* first unused entry */
+  cdata->nomagic = 0;  /* Use a 3-byte magic number header, unless old file */
+  cdata->block_compress = BLOCK_MASK;
+  cdata->clear_flg = 0;
+  cdata->ratio = 0;
+  cdata->checkpoint = CHECK_GAP;
+
+  cdata->input_stream = 0;
+  cdata->output_stream = 0;
+  cdata->client_data = 0;
+  return 1;
+}
+
+/*
+ * compress stdin to stdout
+ *
+ * Algorithm:  use open addressing double hashing (no chaining) on the
+ * prefix code / next character combination.  We do a variant of Knuth's
+ * algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
+ * secondary probe.  Here, the modular division first probe is gives way
+ * to a faster exclusive-or manipulation.  Also do block compression with
+ * an adaptive reset, whereby the code table is cleared when the compression
+ * ratio decreases, but after the table fills.  The variable-length output
+ * codes are re-sized at this point, and a special CLEAR code is generated
+ * for the decompressor.  Late addition:  construct the table according to
+ * file size for noticeable speed improvement on small files.  Please direct
+ * questions about this implementation to ames!jaw.
+ */
+
+int cmcompress_compress_start(struct cmcompress_stream* cdata)
+{
+#ifndef COMPATIBLE
+  if (cdata->nomagic == 0)
+    {
+    char headLast = (char)(cdata->maxbits | cdata->block_compress);
+    cdata->output_stream(cdata, magic_header, 2);
+    cdata->output_stream(cdata, &headLast, 1);
+    if(ferror(stdout))
+      {
+      printf("Error...\n");
+      }
+    }
+#endif /* COMPATIBLE */
+
+  cdata->offset = 0;
+  cdata->bytes_out = 3;    /* includes 3-byte header mojo */
+  cdata->out_count = 0;
+  cdata->clear_flg = 0;
+  cdata->ratio = 0;
+  cdata->in_count = 1;
+  cdata->checkpoint = CHECK_GAP;
+  cdata->maxcode = MAXCODE(cdata->n_bits = INIT_BITS);
+  cdata->free_ent = ((cdata->block_compress) ? FIRST : 256 );
+
+  cdata->first_pass = 1;
+
+  cdata->hshift = 0;
+  for ( cdata->fcode = (long) cdata->hsize;  cdata->fcode < 65536L; cdata->fcode *= 2L )
+    {
+    cdata->hshift++;
+    }
+  cdata->hshift = 8 - cdata->hshift;    /* set hash code range bound */
+
+  cdata->hsize_reg = cdata->hsize;
+  cl_hash(cdata, (count_int) cdata->hsize_reg);    /* clear hash table */
+
+  return 1;
+}
+
+int cmcompress_compress(struct cmcompress_stream* cdata, void* buff, size_t n)
+{
+  register code_int i;
+  register int c;
+  register int disp;
+
+  unsigned char* input_buffer = (unsigned char*)buff;
+
+  size_t cc;
+
+  /*printf("cmcompress_compress(%p, %p, %d)\n", cdata, buff, n);*/
+
+  if ( cdata->first_pass )
+    {
+    cdata->ent = input_buffer[0];
+    ++ input_buffer;
+    -- n;
+    cdata->first_pass = 0;
+    }
+
+  for ( cc = 0; cc < n; ++ cc )
+    {
+    c = input_buffer[cc];
+    cdata->in_count++;
+    cdata->fcode = (long) (((long) c << cdata->maxbits) + cdata->ent);
+    i = ((c << cdata->hshift) ^ cdata->ent);  /* xor hashing */
+
+    if ( htabof (i) == cdata->fcode )
+      {
+      cdata->ent = codetabof (i);
+      continue;
+      }
+    else if ( (long)htabof (i) < 0 )  /* empty slot */
+      {
+      goto nomatch;
+      }
+    disp = cdata->hsize_reg - i;    /* secondary hash (after G. Knott) */
+    if ( i == 0 )
+      {
+      disp = 1;
+      }
+probe:
+    if ( (i -= disp) < 0 )
+      {
+      i += cdata->hsize_reg;
+      }
+
+    if ( htabof (i) == cdata->fcode )
+      {
+      cdata->ent = codetabof (i);
+      continue;
+      }
+    if ( (long)htabof (i) > 0 )
+      {
+      goto probe;
+      }
+nomatch:
+    output(cdata, (code_int) cdata->ent );
+    cdata->out_count++;
+    cdata->ent = c;
+    if (
+#ifdef SIGNED_COMPARE_SLOW
+      (unsigned) cdata->free_ent < (unsigned) cdata->maxmaxcode
+#else
+      cdata->free_ent < cdata->maxmaxcode
+#endif
+    )
+      {
+      codetabof (i) = cdata->free_ent++;  /* code -> hashtable */
+      htabof (i) = cdata->fcode;
+      }
+    else if ( (count_int)cdata->in_count >= cdata->checkpoint && cdata->block_compress )
+      {
+      cl_block (cdata);
+      }
+    }
+
+  return 1;
+}
+
+int cmcompress_compress_finalize(struct cmcompress_stream* cdata)
+{
+  /*
+   * Put out the final code.
+   */
+  output(cdata, (code_int)cdata->ent );
+  cdata->out_count++;
+  output(cdata, (code_int)-1 );
+
+  if(cdata->bytes_out > cdata->in_count)  /* exit(2) if no savings */
+    {
+    return 0;
+    }
+  return 1;
+}
+
+void cl_block (struct cmcompress_stream* cdata)    /* table clear for block compress */
+{
+  register long int rat;
+
+  cdata->checkpoint = cdata->in_count + CHECK_GAP;
+#ifdef DEBUG
+  if ( cdata->debug )
+    {
+    fprintf ( stderr, "count: %ld, ratio: ", cdata->in_count );
+    prratio ( stderr, cdata->in_count, cdata->bytes_out );
+    fprintf ( stderr, "\n");
+    }
+#endif /* DEBUG */
+
+  if(cdata->in_count > 0x007fffff)
+    {  /* shift will overflow */
+    rat = cdata->bytes_out >> 8;
+    if(rat == 0)
+      {    /* Don't divide by zero */
+      rat = 0x7fffffff;
+      }
+    else
+      {
+      rat = cdata->in_count / rat;
+      }
+    }
+  else
+    {
+    rat = (cdata->in_count << 8) / cdata->bytes_out;  /* 8 fractional bits */
+    }
+  if ( rat > cdata->ratio )
+    {
+    cdata->ratio = rat;
+    }
+  else
+    {
+    cdata->ratio = 0;
+#ifdef DEBUG
+    if(cdata->verbose)
+      {
+      dump_tab();  /* dump string table */
+      }
+#endif
+    cl_hash (cdata, (count_int) cdata->hsize );
+    cdata->free_ent = FIRST;
+    cdata->clear_flg = 1;
+    output (cdata, (code_int) CLEAR );
+#ifdef DEBUG
+    if(cdata->debug)
+      {
+      fprintf ( stderr, "clear\n" );
+      }
+#endif /* DEBUG */
+    }
+}
+
+void cl_hash(struct cmcompress_stream* cdata, count_int hsize)    /* reset code table */
+{
+  register count_int *htab_p = cdata->htab+hsize;
+  register long i;
+  register long m1 = -1;
+
+  i = hsize - 16;
+  do
+    {        /* might use Sys V memset(3) here */
+    *(htab_p-16) = m1;
+    *(htab_p-15) = m1;
+    *(htab_p-14) = m1;
+    *(htab_p-13) = m1;
+    *(htab_p-12) = m1;
+    *(htab_p-11) = m1;
+    *(htab_p-10) = m1;
+    *(htab_p-9) = m1;
+    *(htab_p-8) = m1;
+    *(htab_p-7) = m1;
+    *(htab_p-6) = m1;
+    *(htab_p-5) = m1;
+    *(htab_p-4) = m1;
+    *(htab_p-3) = m1;
+    *(htab_p-2) = m1;
+    *(htab_p-1) = m1;
+    htab_p -= 16;
+    }
+  while ((i -= 16) >= 0);
+  for ( i += 16; i > 0; i-- )
+    {
+    *--htab_p = m1;
+    }
+}
+
+#if defined(DEBUG)
+void prratio(FILE *stream, long int num, long int den)
+{
+  register int q;      /* Doesn't need to be long */
+
+  if(num > 214748L)
+    {    /* 2147483647/10000 */
+    q = num / (den / 10000L);
+    }
+  else
+    {
+    q = 10000L * num / den;    /* Long calculations, though */
+    }
+  if (q < 0)
+    {
+    putc('-', stream);
+    q = -q;
+    }
+  fprintf(stream, "%d.%02d%%", q / 100, q % 100);
+}
+#endif
+
+/*-
+ * Output the given code.
+ * Inputs:
+ *   code:  A n_bits-bit integer.  If == -1, then EOF.  This assumes
+ *    that n_bits =< (long)wordsize - 1.
+ * Outputs:
+ *   Outputs code to the file.
+ * Assumptions:
+ *  Chars are 8 bits long.
+ * Algorithm:
+ *   Maintain a BITS character long buffer (so that 8 codes will
+ * fit in it exactly).  Use the VAX insv instruction to insert each
+ * code in turn.  When the buffer fills up empty it and start over.
+ */
+
+static char buf[BITS];
+
+#ifndef vax
+char_type lmask[9] = {0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80, 0x00};
+char_type rmask[9] = {0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
+#endif /* vax */
+
+void output(struct cmcompress_stream* cdata, code_int  code)
+{
+#ifdef DEBUG
+  static int col = 0;
+#endif /* DEBUG */
+
+  /*
+   * On the VAX, it is important to have the register declarations
+   * in exactly the order given, or the asm will break.
+   */
+  register int r_off = cdata->offset, bits= cdata->n_bits;
+  register char * bp = buf;
+
+#ifdef DEBUG
+  if ( verbose )
+    {
+    fprintf( stderr, "%5d%c", code,
+      (col+=6) >= 74 ? (col = 0, '\n') : ' ' );
+    }
+#endif /* DEBUG */
+  if ( code >= 0 )
+    {
+#if defined(vax) && !defined(__GNUC__)
+    /*
+     * VAX and PCC DEPENDENT!! Implementation on other machines is
+     * below.
+     *
+     * Translation: Insert BITS bits from the argument starting at
+     * cdata->offset bits from the beginning of buf.
+     */
+    0;  /* Work around for pcc -O bug with asm and if stmt */
+    asm( "insv  4(ap),r11,r10,(r9)" );
+#else
+    /*
+     * byte/bit numbering on the VAX is simulated by the following code
+     */
+    /*
+     * Get to the first byte.
+     */
+    bp += (r_off >> 3);
+    r_off &= 7;
+    /*
+     * Since code is always >= 8 bits, only need to mask the first
+     * hunk on the left.
+     */
+    *bp = (*bp & rmask[r_off]) | ((code << r_off) & lmask[r_off]);
+    bp++;
+    bits -= (8 - r_off);
+    code >>= 8 - r_off;
+    /* Get any 8 bit parts in the middle (<=1 for up to 16 bits). */
+    if ( bits >= 8 )
+      {
+      *bp++ = code;
+      code >>= 8;
+      bits -= 8;
+      }
+    /* Last bits. */
+    if(bits)
+      {
+      *bp = code;
+      }
+#endif /* vax */
+    cdata->offset += cdata->n_bits;
+    if ( cdata->offset == (cdata->n_bits << 3) )
+      {
+      bp = buf;
+      bits = cdata->n_bits;
+      cdata->bytes_out += bits;
+      do
+        {
+        if ( cdata->output_stream(cdata, bp, 1) != 1 )
+          //putchar(*bp++);
+          //if (ferror(stdout))
+          {
+          writeerr();
+          }
+        bp++;
+        }
+      while(--bits);
+      cdata->offset = 0;
+      }
+
+    /*
+     * If the next entry is going to be too big for the code size,
+     * then increase it, if possible.
+     */
+    if ( cdata->free_ent > cdata->maxcode || (cdata->clear_flg > 0))
+      {
+      /*
+       * Write the whole buffer, because the input side won't
+       * discover the size increase until after it has read it.
+       */
+      if ( cdata->offset > 0 )
+        {
+        if ( cdata->output_stream(cdata, buf, cdata->n_bits) != cdata->n_bits )
+          //if( fwrite( buf, 1, cdata->n_bits, stdout ) != cdata->n_bits)
+          {
+          writeerr();
+          }
+        cdata->bytes_out += cdata->n_bits;
+        }
+      cdata->offset = 0;
+
+      if ( cdata->clear_flg )
+        {
+        cdata->maxcode = MAXCODE (cdata->n_bits = INIT_BITS);
+        cdata->clear_flg = 0;
+        }
+      else
+        {
+        cdata->n_bits++;
+        if ( cdata->n_bits == cdata->maxbits )
+          {
+          cdata->maxcode = cdata->maxmaxcode;
+          }
+        else
+          {
+          cdata->maxcode = MAXCODE(cdata->n_bits);
+          }
+        }
+#ifdef DEBUG
+      if ( debug )
+        {
+        fprintf( stderr, "\nChange to %d bits\n", cdata->n_bits );
+        col = 0;
+        }
+#endif /* DEBUG */
+      }
+    }
+  else
+    {
+    /*
+     * At EOF, write the rest of the buffer.
+     */
+    if ( cdata->offset > 0 )
+      {
+      cdata->offset = (cdata->offset + 7) / 8;
+      if ( cdata->output_stream(cdata, buf, cdata->offset ) != cdata->offset )
+        //if( fwrite( buf, 1, cdata->offset, stdout ) != cdata->offset )
+        {
+        writeerr();
+        }
+      cdata->bytes_out += cdata->offset;
+      }
+    cdata->offset = 0;
+    (void)fflush( stdout );
+    if( ferror( stdout ) )
+      {
+      writeerr();
+      }
+#ifdef DEBUG
+    if ( verbose )
+      {
+      fprintf( stderr, "\n" );
+      }
+#endif
+    }
+}
+
+void writeerr()
+{
+  (void)fprintf(stderr, "compress: %s\n",
+    strerror(errno));
+  exit(1);
+}
+