compress/doc/revision.log

   1 /* $FreeBSD: src/usr.bin/compress/doc/revision.log,v 1.5 2011/03/31 14:35:33 emaste Exp $ */
   2
   3 /*
   4  * $Header: compress.c,v 4.0 85/07/30 12:50:00 joe Release $
   5  *
   6  * Revision 4.0  85/07/30  12:50:00  joe
   7  * Removed ferror() calls in output routine on every output except first.
   8  * Prepared for release to the world.
   9  *
  10  * Revision 3.6  85/07/04  01:22:21  joe
  11  * Remove much wasted storage by overlaying hash table with the tables
  12  * used by decompress: tab_suffix[1<<BITS], stack[8000].  Updated USERMEM
  13  * computations.  Fixed dump_tab() DEBUG routine.
  14  *
  15  * Revision 3.5  85/06/30  20:47:21  jaw
  16  * Change hash function to use exclusive-or.  Rip out hash cache.  These
  17  * speedups render the megamemory version defunct, for now.  Make decoder
  18  * stack global.  Parts of the RCS trunks 2.7, 2.6, and 2.1 no longer apply.
  19  *
  20  * Revision 3.4  85/06/27  12:00:00  ken
  21  * Get rid of all floating-point calculations by doing all compression ratio
  22  * calculations in fixed point.
  23  *
  24  * Revision 3.3  85/06/24  21:53:24  joe
  25  * Incorporate portability suggestion for M_XENIX.  Got rid of text on #else
  26  * and #endif lines.  Cleaned up #ifdefs for vax and interdata.
  27  *
  28  * Revision 3.2  85/06/06  21:53:24  jaw
  29  * Incorporate portability suggestions for Z8000, IBM PC/XT from mailing list.
  30  * Default to "quiet" output (no compression statistics).
  31  *
  32  * Revision 3.1  85/05/12  18:56:13  jaw
  33  * Integrate decompress() stack speedups (from early pointer mods by McKie).
  34  * Repair multi-file USERMEM gaffe.  Unify 'force' flags to mimic semantics
  35  * of SVR2 'pack'.  Streamline block-compress table clear logic.  Increase
  36  * output byte count by magic number size.
  37  *
  38  * Revision 3.0   84/11/27  11:50:00  petsd!joe
  39  * Set HSIZE depending on BITS.  Set BITS depending on USERMEM.  Unrolled
  40  * loops in clear routines.  Added "-C" flag for 2.0 compatibility.  Used
  41  * unsigned compares on Perkin-Elmer.  Fixed foreground check.
  42  *
  43  * Revision 2.7   84/11/16  19:35:39  ames!jaw
  44  * Cache common hash codes based on input statistics; this improves
  45  * performance for low-density raster images.  Pass on #ifdef bundle
  46  * from Turkowski.
  47  *
  48  * Revision 2.6   84/11/05  19:18:21  ames!jaw
  49  * Vary size of hash tables to reduce time for small files.
  50  * Tune PDP-11 hash function.
  51  *
  52  * Revision 2.5   84/10/30  20:15:14  ames!jaw
  53  * Junk chaining; replace with the simpler (and, on the VAX, faster)
  54  * double hashing, discussed within.  Make block compression standard.
  55  *
  56  * Revision 2.4   84/10/16  11:11:11  ames!jaw
  57  * Introduce adaptive reset for block compression, to boost the rate
  58  * another several percent.  (See mailing list notes.)
  59  *
  60  * Revision 2.3   84/09/22  22:00:00  petsd!joe
  61  * Implemented "-B" block compress.  Implemented REVERSE sorting of tab_next.
  62  * Bug fix for last bits.  Changed fwrite to putchar loop everywhere.
  63  *
  64  * Revision 2.2   84/09/18  14:12:21  ames!jaw
  65  * Fold in news changes, small machine typedef from thomas,
  66  * #ifdef interdata from joe.
  67  *
  68  * Revision 2.1   84/09/10  12:34:56  ames!jaw
  69  * Configured fast table lookup for 32-bit machines.
  70  * This cuts user time in half for b <= FBITS, and is useful for news batching
  71  * from VAX to PDP sites.  Also sped up decompress() [fwrite->putc] and
  72  * added signal catcher [plus beef in writeerr()] to delete effluvia.
  73  *
  74  * Revision 2.0   84/08/28  22:00:00  petsd!joe
  75  * Add check for foreground before prompting user.  Insert maxbits into
  76  * compressed file.  Force file being uncompressed to end with ".Z".
  77  * Added "-c" flag and "zcat".  Prepared for release.
  78  *
  79  * Revision 1.10  84/08/24  18:28:00  turtlevax!ken
  80  * Will only compress regular files (no directories), added a magic number
  81  * header (plus an undocumented -n flag to handle old files without headers),
  82  * added -f flag to force overwriting of possibly existing destination file,
  83  * otherwise the user is prompted for a response.  Will tack on a .Z to a
  84  * filename if it doesn't have one when decompressing.  Will only replace
  85  * file if it was compressed.
  86  *
  87  * Revision 1.9  84/08/16  17:28:00  turtlevax!ken
  88  * Removed scanargs(), getopt(), added .Z extension and unlimited number of
  89  * filenames to compress.  Flags may be clustered (-Ddvb12) or separated
  90  * (-D -d -v -b 12), or combination thereof.  Modes and other status is
  91  * copied with copystat().  -O bug for 4.2 seems to have disappeared with
  92  * 1.8.
  93  *
  94  * Revision 1.8  84/08/09  23:15:00  joe
  95  * Made it compatible with vax version, installed jim's fixes/enhancements
  96  *
  97  * Revision 1.6  84/08/01  22:08:00  joe
  98  * Sped up algorithm significantly by sorting the compress chain.
  99  *
 100  * Revision 1.5  84/07/13  13:11:00  srd
 101  * Added C version of vax asm routines.  Changed structure to arrays to
 102  * save much memory.  Do unsigned compares where possible (faster on
 103  * Perkin-Elmer)
 104  *
 105  * Revision 1.4  84/07/05  03:11:11  thomas
 106  * Clean up the code a little and lint it.  (Lint complains about all
 107  * the regs used in the asm, but I'm not going to "fix" this.)
 108  *
 109  * Revision 1.3  84/07/05  02:06:54  thomas
 110  * Minor fixes.
 111  *
 112  * Revision 1.2  84/07/05  00:27:27  thomas
 113  * Add variable bit length output.
 114  *
 115  */
 116
 117 static char rcs_ident[] =
 118         "$Header: compress.c,v 4.0 85/07/30 12:50:00 joe Release $";