initial revision

15 files changed, 4476 insertions, 0 deletions

diff --git a/isys/gzlib/Makefile b/isys/gzlib/Makefile
new file mode 100644
index 000000000..5f2fa85b3
--- /dev/null
+++ b/isys/gzlib/Makefile
@@ -0,0 +1,11 @@
+include ../../Makefile.inc
+
+CC = diet gcc
+CFLAGS += -I . -g
+SOURCES = bits.c gzip.c inflate.c lzw.c trees.c unzip.c util.c zip.c binding.c
+OBJS = bits.o gzip.o inflate.o lzw.o trees.o unzip.o util.o zip.o binding.o
+
+all: libgunzip.a($(OBJS))
+
+clean:	
+	rm -f libgunzip.a $(OBJS)
diff --git a/isys/gzlib/binding.c b/isys/gzlib/binding.c
new file mode 100644
index 000000000..ca93153a0
--- /dev/null
+++ b/isys/gzlib/binding.c
@@ -0,0 +1,67 @@
+#include <sys/signal.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+
+#include "gzlib.h"
+
+struct gzFile_s {
+    int fd;
+};
+
+gzFile gunzip_open(const char * file) {
+    int fd;
+    int p[2];
+    void * oldsig;
+    pid_t child;
+    gzFile str;
+
+    fd = open(file, O_RDONLY);
+    if (fd < 0) return NULL;
+
+    pipe(p);
+
+    oldsig = signal(SIGCLD, SIG_IGN);
+
+    child = fork();
+    if (!child) {
+	if (fork()) exit(0);
+
+	dup2(fd, 0);
+	dup2(p[1], 1);
+	close(p[0]);
+	close(p[1]);
+	gunzip_main();
+	exit(0);
+    }
+
+    waitpid(child, NULL, 0);
+    signal(SIGCLD, oldsig);
+
+    close(p[1]);
+
+    str = malloc(sizeof(*str));
+    str->fd = p[0];
+
+    return str;
+}
+
+int gunzip_read(gzFile str, void * buf, int bytes) {
+    int pos = 0;
+    int i;
+
+    while ((pos != bytes) &&
+      (i = read(str->fd, ((char *) buf) + pos, bytes - pos)) > 0)
+	pos += i;
+
+    if (i < 0) return -1;
+
+    return pos;
+}
+
+int gunzip_close(gzFile str) {
+    close(str->fd);
+    
+    return 0;
+}
+
diff --git a/isys/gzlib/bits.c b/isys/gzlib/bits.c
new file mode 100644
index 000000000..3745a9ef3
--- /dev/null
+++ b/isys/gzlib/bits.c
@@ -0,0 +1,206 @@
+/* bits.c -- output variable-length bit strings
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+
+/*
+ *  PURPOSE
+ *
+ *      Output variable-length bit strings. Compression can be done
+ *      to a file or to memory. (The latter is not supported in this version.)
+ *
+ *  DISCUSSION
+ *
+ *      The PKZIP "deflate" file format interprets compressed file data
+ *      as a sequence of bits.  Multi-bit strings in the file may cross
+ *      byte boundaries without restriction.
+ *
+ *      The first bit of each byte is the low-order bit.
+ *
+ *      The routines in this file allow a variable-length bit value to
+ *      be output right-to-left (useful for literal values). For
+ *      left-to-right output (useful for code strings from the tree routines),
+ *      the bits must have been reversed first with bi_reverse().
+ *
+ *      For in-memory compression, the compressed bit stream goes directly
+ *      into the requested output buffer. The input data is read in blocks
+ *      by the mem_read() function. The buffer is limited to 64K on 16 bit
+ *      machines.
+ *
+ *  INTERFACE
+ *
+ *      void bi_init (FILE *zipfile)
+ *          Initialize the bit string routines.
+ *
+ *      void send_bits (int value, int length)
+ *          Write out a bit string, taking the source bits right to
+ *          left.
+ *
+ *      int bi_reverse (int value, int length)
+ *          Reverse the bits of a bit string, taking the source bits left to
+ *          right and emitting them right to left.
+ *
+ *      void bi_windup (void)
+ *          Write out any remaining bits in an incomplete byte.
+ *
+ *      void copy_block(char *buf, unsigned len, int header)
+ *          Copy a stored block to the zip file, storing first the length and
+ *          its one's complement if requested.
+ *
+ */
+
+#include <config.h>
+#include "tailor.h"
+#include "gzip.h"
+#include "crypt.h"
+
+#ifdef DEBUG
+#  include <stdio.h>
+#endif
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+/* ===========================================================================
+ * Local data used by the "bit string" routines.
+ */
+
+local file_t zfile; /* output gzip file */
+
+local unsigned short bi_buf;
+/* Output buffer. bits are inserted starting at the bottom (least significant
+ * bits).
+ */
+
+#define Buf_size (8 * 2*sizeof(char))
+/* Number of bits used within bi_buf. (bi_buf might be implemented on
+ * more than 16 bits on some systems.)
+ */
+
+local int bi_valid;
+/* Number of valid bits in bi_buf.  All bits above the last valid bit
+ * are always zero.
+ */
+
+int (*read_buf) OF((char *buf, unsigned size));
+/* Current input function. Set to mem_read for in-memory compression */
+
+#ifdef DEBUG
+  off_t bits_sent;   /* bit length of the compressed data */
+#endif
+
+/* ===========================================================================
+ * Initialize the bit string routines.
+ */
+void bi_init (zipfile)
+    file_t zipfile; /* output zip file, NO_FILE for in-memory compression */
+{
+    zfile  = zipfile;
+    bi_buf = 0;
+    bi_valid = 0;
+#ifdef DEBUG
+    bits_sent = 0L;
+#endif
+
+    /* Set the defaults for file compression. They are set by memcompress
+     * for in-memory compression.
+     */
+    if (zfile != NO_FILE) {
+	read_buf  = file_read;
+    }
+}
+
+/* ===========================================================================
+ * Send a value on a given number of bits.
+ * IN assertion: length <= 16 and value fits in length bits.
+ */
+void send_bits(value, length)
+    int value;  /* value to send */
+    int length; /* number of bits */
+{
+#ifdef DEBUG
+    Tracev((stderr," l %2d v %4x ", length, value));
+    Assert(length > 0 && length <= 15, "invalid length");
+    bits_sent += (off_t)length;
+#endif
+    /* If not enough room in bi_buf, use (valid) bits from bi_buf and
+     * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
+     * unused bits in value.
+     */
+    if (bi_valid > (int)Buf_size - length) {
+        bi_buf |= (value << bi_valid);
+        put_short(bi_buf);
+        bi_buf = (ush)value >> (Buf_size - bi_valid);
+        bi_valid += length - Buf_size;
+    } else {
+        bi_buf |= value << bi_valid;
+        bi_valid += length;
+    }
+}
+
+/* ===========================================================================
+ * Reverse the first len bits of a code, using straightforward code (a faster
+ * method would use a table)
+ * IN assertion: 1 <= len <= 15
+ */
+unsigned bi_reverse(code, len)
+    unsigned code; /* the value to invert */
+    int len;       /* its bit length */
+{
+    register unsigned res = 0;
+    do {
+        res |= code & 1;
+        code >>= 1, res <<= 1;
+    } while (--len > 0);
+    return res >> 1;
+}
+
+/* ===========================================================================
+ * Write out any remaining bits in an incomplete byte.
+ */
+void bi_windup()
+{
+    if (bi_valid > 8) {
+        put_short(bi_buf);
+    } else if (bi_valid > 0) {
+        put_byte(bi_buf);
+    }
+    bi_buf = 0;
+    bi_valid = 0;
+#ifdef DEBUG
+    bits_sent = (bits_sent+7) & ~7;
+#endif
+}
+
+/* ===========================================================================
+ * Copy a stored block to the zip file, storing first the length and its
+ * one's complement if requested.
+ */
+void copy_block(buf, len, header)
+    char     *buf;    /* the input data */
+    unsigned len;     /* its length */
+    int      header;  /* true if block header must be written */
+{
+    bi_windup();              /* align on byte boundary */
+
+    if (header) {
+        put_short((ush)len);   
+        put_short((ush)~len);
+#ifdef DEBUG
+        bits_sent += 2*16;
+#endif
+    }
+#ifdef DEBUG
+    bits_sent += (off_t)len<<3;
+#endif
+    while (len--) {
+#ifdef CRYPT
+        int t;
+	if (key) zencode(*buf, t);
+#endif
+	put_byte(*buf++);
+    }
+}
diff --git a/isys/gzlib/config.h b/isys/gzlib/config.h
new file mode 100644
index 000000000..f578992c2
--- /dev/null
+++ b/isys/gzlib/config.h
@@ -0,0 +1,95 @@
+/* config.h.  Generated automatically by configure.  */
+/* config.h.in.  Generated automatically from configure.in by autoheader.  */
+
+/* Define if on AIX 3.
+   System headers sometimes define this.
+   We just want to avoid a redefinition error message.  */
+#ifndef _ALL_SOURCE
+/* #undef _ALL_SOURCE */
+#endif
+
+/* Define to empty if the keyword does not work.  */
+/* #undef const */
+
+/* Define if on MINIX.  */
+/* #undef _MINIX */
+
+/* Define to `long' if <sys/types.h> doesn't define.  */
+/* #undef off_t */
+
+/* Define if the system does not provide POSIX.1 features except
+   with this defined.  */
+/* #undef _POSIX_1_SOURCE */
+
+/* Define if you need to in order for stat and other things to work.  */
+/* #undef _POSIX_SOURCE */
+
+/* Define as the return type of signal handlers (int or void).  */
+#define RETSIGTYPE void
+
+/* Define to `unsigned' if <sys/types.h> doesn't define.  */
+/* #undef size_t */
+
+/* Define if you have the ANSI C header files.  */
+#define STDC_HEADERS 1
+
+/* Define if you have the utime function.  */
+#define HAVE_UTIME 1
+
+/* Define if you have the <dirent.h> header file.  */
+#define HAVE_DIRENT_H 1
+
+/* Define if you have the <fcntl.h> header file.  */
+#define HAVE_FCNTL_H 1
+
+/* Define if you have the <limits.h> header file.  */
+#define HAVE_LIMITS_H 1
+
+/* Define if you have the <memory.h> header file.  */
+#define HAVE_MEMORY_H 1
+
+/* Define if you have the <ndir.h> header file.  */
+/* #undef HAVE_NDIR_H */
+
+/* Define if you have the <stdlib.h> header file.  */
+#define HAVE_STDLIB_H 1
+
+/* Define if you have the <string.h> header file.  */
+#define HAVE_STRING_H 1
+
+/* Define if you have the <sys/dir.h> header file.  */
+/* #undef HAVE_SYS_DIR_H */
+
+/* Define if you have the <sys/ndir.h> header file.  */
+/* #undef HAVE_SYS_NDIR_H */
+
+/* Define if you have the <sys/utime.h> header file.  */
+/* #undef HAVE_SYS_UTIME_H */
+
+/* Define if you have the <time.h> header file.  */
+#define HAVE_TIME_H 1
+
+/* Define if you have the <unistd.h> header file.  */
+#define HAVE_UNISTD_H 1
+
+/* Define if you have the <utime.h> header file.  */
+#define HAVE_UTIME_H 1
+
+/* Name of package */
+#define PACKAGE "gzip"
+
+/* Version number of package */
+#define VERSION "1.3"
+
+/* Number of bits in a file offset, on hosts where this is settable. */
+#define _FILE_OFFSET_BITS 64
+
+/* Define to make fseeko etc. visible, on some hosts. */
+/* #undef _LARGEFILE_SOURCE */
+
+/* Define for large files, on AIX-style hosts. */
+/* #undef _LARGE_FILES */
+
+/* Define if an assembler version of longest_match is available. */
+/* #undef ASMV */
+
diff --git a/isys/gzlib/gzip.c b/isys/gzlib/gzip.c
new file mode 100644
index 000000000..36eca62c2
--- /dev/null
+++ b/isys/gzlib/gzip.c
@@ -0,0 +1,568 @@
+/* gzip (GNU zip) -- compress files with zip algorithm and 'compress' interface
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * The unzip code was written and put in the public domain by Mark Adler.
+ * Portions of the lzw code are derived from the public domain 'compress'
+ * written by Spencer Thomas, Joe Orost, James Woods, Jim McKie, Steve Davies,
+ * Ken Turkowski, Dave Mack and Peter Jannesen.
+ *
+ * See the license_msg below and the file COPYING for the software license.
+ * See the file algorithm.doc for the compression algorithms and file formats.
+ */
+
+
+/* Compress files with zip algorithm and 'compress' interface.
+ * See usage() and help() functions below for all options.
+ * Outputs:
+ *        file.gz:   compressed file with same mode, owner, and utimes
+ *     or stdout with -c option or if stdin used as input.
+ * If the output file name had to be truncated, the original name is kept
+ * in the compressed file.
+ * On MSDOS, file.tmp -> file.tmz. On VMS, file.tmp -> file.tmp-gz.
+ *
+ * Using gz on MSDOS would create too many file name conflicts. For
+ * example, foo.txt -> foo.tgz (.tgz must be reserved as shorthand for
+ * tar.gz). Similarly, foo.dir and foo.doc would both be mapped to foo.dgz.
+ * I also considered 12345678.txt -> 12345txt.gz but this truncates the name
+ * too heavily. There is no ideal solution given the MSDOS 8+3 limitation. 
+ *
+ * For the meaning of all compilation flags, see comments in Makefile.in.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+#include <config.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <sys/stat.h>
+#include <errno.h>
+
+#include "tailor.h"
+#include "gzip.h"
+#include "lzw.h"
+
+		/* configuration */
+
+#ifdef HAVE_TIME_H
+#  include <time.h>
+#else
+#  include <sys/time.h>
+#endif
+
+#ifdef HAVE_FCNTL_H
+#  include <fcntl.h>
+#endif
+
+#ifdef HAVE_LIMITS_H
+#  include <limits.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h>
+#endif
+
+#if defined STDC_HEADERS || defined HAVE_STDLIB_H
+#  include <stdlib.h>
+#else
+   extern int errno;
+#endif
+
+#ifdef HAVE_DIRENT_H
+#  include <dirent.h>
+#  define NAMLEN(direct) strlen((direct)->d_name)
+#  define DIR_OPT "DIRENT"
+#else
+#  define dirent direct
+#  define NAMLEN(direct) ((direct)->d_namlen)
+#  ifdef HAVE_SYS_NDIR_H
+#    include <sys/ndir.h>
+#    define DIR_OPT "SYS_NDIR"
+#  endif
+#  ifdef HAVE_SYS_DIR_H
+#    include <sys/dir.h>
+#    define DIR_OPT "SYS_DIR"
+#  endif
+#  ifdef HAVE_NDIR_H
+#    include <ndir.h>
+#    define DIR_OPT "NDIR"
+#  endif
+#  ifndef DIR_OPT
+#    define DIR_OPT "NO_DIR"
+#  endif
+#endif
+
+#ifdef CLOSEDIR_VOID
+# define CLOSEDIR(d) (closedir(d), 0)
+#else
+# define CLOSEDIR(d) closedir(d)
+#endif
+
+#ifdef HAVE_UTIME
+#  ifdef HAVE_UTIME_H
+#    include <utime.h>
+#    define TIME_OPT "UTIME"
+#  else
+#    ifdef HAVE_SYS_UTIME_H
+#      include <sys/utime.h>
+#      define TIME_OPT "SYS_UTIME"
+#    else
+       struct utimbuf {
+         time_t actime;
+         time_t modtime;
+       };
+#      define TIME_OPT "STRUCT_UTIMBUF"
+#    endif
+#  endif
+#else
+#  define TIME_OPT "NO_UTIME"
+#endif
+
+#if !defined(S_ISDIR) && defined(S_IFDIR)
+#  define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
+#endif
+#if !defined(S_ISREG) && defined(S_IFREG)
+#  define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
+#endif
+
+typedef RETSIGTYPE (*sig_type) OF((int));
+
+#ifndef	O_BINARY
+#  define  O_BINARY  0  /* creation mode for open() */
+#endif
+
+#ifndef O_CREAT
+   /* Pure BSD system? */
+#  include <sys/file.h>
+#  ifndef O_CREAT
+#    define O_CREAT FCREAT
+#  endif
+#  ifndef O_EXCL
+#    define O_EXCL FEXCL
+#  endif
+#endif
+
+#ifndef S_IRUSR
+#  define S_IRUSR 0400
+#endif
+#ifndef S_IWUSR
+#  define S_IWUSR 0200
+#endif
+#define RW_USER (S_IRUSR | S_IWUSR)  /* creation mode for open() */
+
+#ifndef MAX_PATH_LEN
+#  define MAX_PATH_LEN   1024 /* max pathname length */
+#endif
+
+#ifndef SEEK_END
+#  define SEEK_END 2
+#endif
+
+#ifndef CHAR_BIT
+#  define CHAR_BIT 8
+#endif
+
+#ifdef off_t
+  off_t lseek OF((int fd, off_t offset, int whence));
+#endif
+
+#ifndef OFF_T_MIN
+#define OFF_T_MIN (~ (off_t) 0 << (sizeof (off_t) * CHAR_BIT - 1))
+#endif
+
+#ifndef OFF_T_MAX
+#define OFF_T_MAX (~ (off_t) 0 - OFF_T_MIN)
+#endif
+
+		/* global buffers */
+
+DECLARE(uch, inbuf,  INBUFSIZ +INBUF_EXTRA);
+DECLARE(uch, outbuf, OUTBUFSIZ+OUTBUF_EXTRA);
+DECLARE(ush, d_buf,  DIST_BUFSIZE);
+DECLARE(uch, window, 2L*WSIZE);
+#ifndef MAXSEG_64K
+    DECLARE(ush, tab_prefix, 1L<<BITS);
+#else
+    DECLARE(ush, tab_prefix0, 1L<<(BITS-1));
+    DECLARE(ush, tab_prefix1, 1L<<(BITS-1));
+#endif
+
+		/* local variables */
+
+long block_start;
+unsigned strstart;      /* start of string to insert */
+
+int to_stdout = 0;    /* output to stdout (-c) */
+int decompress = 0;   /* decompress (-d) */
+int force = 0;        /* don't ask questions, compress links (-f) */
+int no_name = -1;     /* don't save or restore the original file name */
+int no_time = -1;     /* don't save or restore the original file time */
+int recursive = 0;    /* recurse through directories (-r) */
+int list = 0;         /* list the file contents (-l) */
+int quiet = 0;        /* be very quiet (-q) */
+int do_lzw = 0;       /* generate output compatible with old compress (-Z) */
+int test = 0;         /* test .gz file integrity */
+int foreground;       /* set if program run in foreground */
+char *progname;       /* program name */
+int maxbits = BITS;   /* max bits per code for LZW */
+int method = DEFLATED;/* compression method */
+int level = 6;        /* compression level */
+int exit_code = OK;   /* program exit code */
+int save_orig_name;   /* set if original name must be saved */
+int last_member;      /* set for .zip and .Z files */
+int part_nb;          /* number of parts in .gz file */
+time_t time_stamp;      /* original time stamp (modification time) */
+off_t ifile_size;      /* input file size, -1 for devices (debug only) */
+char *env;            /* contents of GZIP env variable */
+char **args = NULL;   /* argv pointer if GZIP env variable defined */
+char *z_suffix;       /* default suffix (can be set with --suffix) */
+int  z_len;           /* strlen(z_suffix) */
+
+off_t bytes_in;             /* number of input bytes */
+off_t bytes_out;            /* number of output bytes */
+off_t total_in;		    /* input bytes for all files */
+off_t total_out;	    /* output bytes for all files */
+char ifname[MAX_PATH_LEN]; /* input file name */
+char ofname[MAX_PATH_LEN]; /* output file name */
+int  remove_ofname = 0;	   /* remove output file on error */
+struct stat istat;         /* status for input file */
+int  ifd;                  /* input file descriptor */
+int  ofd;                  /* output file descriptor */
+unsigned insize;           /* valid bytes in inbuf */
+unsigned inptr;            /* index of next byte to be processed in inbuf */
+unsigned outcnt;           /* bytes in output buffer */
+
+/* local functions */
+
+local int input_eof	OF((void));
+local void treat_stdin  OF((void));
+local int  get_method   OF((int in));
+local void do_exit      OF((int exitcode));
+int (*work) OF((int infile, int outfile)) = NULL;
+
+#define strequ(s1, s2) (strcmp((s1),(s2)) == 0)
+
+local void progerror (string)
+    char *string;
+{
+    int e = errno;
+    fprintf(stderr, "%s: ", progname);
+    errno = e;
+    perror(string);
+    exit_code = ERROR;
+}
+
+/* ======================================================================== */
+int gunzip_main (void)
+{
+    int file_count;     /* number of files to precess */
+    int proglen;        /* length of progname */
+    int optc;           /* current option */
+    int argc = 1;
+    char *argv[] = { "gunzip ", NULL };
+
+    EXPAND(argc, argv); /* wild card expansion if necessary */
+
+    progname = base_name (argv[0]);
+    proglen = strlen(progname);
+
+    /* Suppress .exe for MSDOS, OS/2 and VMS: */
+    if (proglen > 4 && strequ(progname+proglen-4, ".exe")) {
+        progname[proglen-4] = '\0';
+    }
+
+    /* Add options in GZIP environment variable if there is one */
+    env = add_envopt(&argc, &argv, OPTIONS_VAR);
+    if (env != NULL) args = argv;
+
+    foreground = signal(SIGINT, SIG_IGN) != SIG_IGN;
+    if (foreground) {
+	(void) signal (SIGINT, (sig_type)abort_gzip);
+    }
+#ifdef SIGTERM
+    if (signal(SIGTERM, SIG_IGN) != SIG_IGN) {
+	(void) signal(SIGTERM, (sig_type)abort_gzip);
+    }
+#endif
+#ifdef SIGHUP
+    if (signal(SIGHUP, SIG_IGN) != SIG_IGN) {
+	(void) signal(SIGHUP,  (sig_type)abort_gzip);
+    }
+#endif
+
+#ifndef GNU_STANDARD
+    /* For compatibility with old compress, use program name as an option.
+     * If you compile with -DGNU_STANDARD, this program will behave as
+     * gzip even if it is invoked under the name gunzip or zcat.
+     *
+     * Systems which do not support links can still use -d or -dc.
+     * Ignore an .exe extension for MSDOS, OS/2 and VMS.
+     */
+    if (  strncmp(progname, "un",  2) == 0     /* ungzip, uncompress */
+       || strncmp(progname, "gun", 3) == 0) {  /* gunzip */
+	decompress = 1;
+    } else if (strequ(progname+1, "cat")       /* zcat, pcat, gcat */
+	    || strequ(progname, "gzcat")) {    /* gzcat */
+	decompress = to_stdout = 1;
+    }
+#endif
+
+    z_suffix = Z_SUFFIX;
+    z_len = strlen(z_suffix);
+
+#ifdef SIGPIPE
+    /* Ignore "Broken Pipe" message with --quiet */
+    if (quiet && signal (SIGPIPE, SIG_IGN) != SIG_IGN)
+      signal (SIGPIPE, (sig_type) abort_gzip);
+#endif
+
+    /* By default, save name and timestamp on compression but do not
+     * restore them on decompression.
+     */
+    if (no_time < 0) no_time = decompress;
+    if (no_name < 0) no_name = decompress;
+
+    file_count = argc - optind;
+
+    /* Allocate all global buffers (for DYN_ALLOC option) */
+    ALLOC(uch, inbuf,  INBUFSIZ +INBUF_EXTRA);
+    ALLOC(uch, outbuf, OUTBUFSIZ+OUTBUF_EXTRA);
+    ALLOC(ush, d_buf,  DIST_BUFSIZE);
+    ALLOC(uch, window, 2L*WSIZE);
+#ifndef MAXSEG_64K
+    ALLOC(ush, tab_prefix, 1L<<BITS);
+#else
+    ALLOC(ush, tab_prefix0, 1L<<(BITS-1));
+    ALLOC(ush, tab_prefix1, 1L<<(BITS-1));
+#endif
+
+    treat_stdin();
+
+    do_exit(exit_code);
+    return exit_code; /* just to avoid lint warning */
+}
+
+/* Return nonzero when at end of file on input.  */
+local int
+input_eof ()
+{
+  if (!decompress || last_member)
+    return 1;
+
+  if (inptr == insize)
+    {
+      if (insize != INBUFSIZ || fill_inbuf (1) == EOF)
+	return 1;
+
+      /* Unget the char that fill_inbuf got.  */
+      inptr = 0;
+    }
+
+  return 0;
+}
+
+/* ========================================================================
+ * Compress or decompress stdin
+ */
+local void treat_stdin()
+{
+    strcpy(ifname, "stdin");
+    strcpy(ofname, "stdout");
+
+    /* Get the time stamp on the input file. */
+    time_stamp = 0; /* time unknown by default */
+
+    ifile_size = -1L; /* convention for unknown size */
+
+    clear_bufs(); /* clear input and output buffers */
+    to_stdout = 1;
+    part_nb = 0;
+
+    method = get_method(ifd);
+    if (method < 0) {
+	do_exit(exit_code); /* error message already emitted */
+    }
+
+    /* Actually do the compression/decompression. Loop over zipped members.
+     */
+    for (;;) {
+	if ((*work)(fileno(stdin), fileno(stdout)) != OK) return;
+
+	if (input_eof ())
+	  break;
+
+	method = get_method(ifd);
+	if (method < 0) return; /* error message already emitted */
+	bytes_out = 0;            /* required for length check */
+    }
+
+}
+
+
+/* ========================================================================
+ * Check the magic number of the input file and update ofname if an
+ * original name was given and to_stdout is not set.
+ * Return the compression method, -1 for error, -2 for warning.
+ * Set inptr to the offset of the next byte to be processed.
+ * Updates time_stamp if there is one and --no-time is not used.
+ * This function may be called repeatedly for an input file consisting
+ * of several contiguous gzip'ed members.
+ * IN assertions: there is at least one remaining compressed member.
+ *   If the member is a zip file, it must be the only one.
+ */
+local int get_method(in)
+    int in;        /* input file descriptor */
+{
+    uch flags;     /* compression flags */
+    char magic[2]; /* magic header */
+    int imagic1;   /* like magic[1], but can represent EOF */
+    ulg stamp;     /* time stamp */
+
+    /* If --force and --stdout, zcat == cat, so do not complain about
+     * premature end of file: use try_byte instead of get_byte.
+     */
+    if (force && to_stdout) {
+	magic[0] = (char)try_byte();
+	imagic1 = try_byte ();
+	magic[1] = (char) imagic1;
+	/* If try_byte returned EOF, magic[1] == (char) EOF.  */
+    } else {
+	magic[0] = (char)get_byte();
+	magic[1] = (char)get_byte();
+	imagic1 = 0; /* avoid lint warning */
+    }
+    method = -1;                 /* unknown yet */
+    part_nb++;                   /* number of parts in gzip file */
+    header_bytes = 0;
+    last_member = RECORD_IO;
+    /* assume multiple members in gzip file except for record oriented I/O */
+
+    if (memcmp(magic, GZIP_MAGIC, 2) == 0
+        || memcmp(magic, OLD_GZIP_MAGIC, 2) == 0) {
+
+	method = (int)get_byte();
+	if (method != DEFLATED) {
+	    fprintf(stderr,
+		    "%s: %s: unknown method %d -- get newer version of gzip\n",
+		    progname, ifname, method);
+	    exit_code = ERROR;
+	    return -1;
+	}
+	work = unzip;
+	flags  = (uch)get_byte();
+
+	stamp  = (ulg)get_byte();
+	stamp |= ((ulg)get_byte()) << 8;
+	stamp |= ((ulg)get_byte()) << 16;
+	stamp |= ((ulg)get_byte()) << 24;
+	if (stamp != 0 && !no_time) time_stamp = stamp;
+
+	(void)get_byte();  /* Ignore extra flags for the moment */
+	(void)get_byte();  /* Ignore OS type for the moment */
+
+	if ((flags & CONTINUATION) != 0) {
+	    unsigned part = (unsigned)get_byte();
+	    part |= ((unsigned)get_byte())<<8;
+	}
+	if ((flags & EXTRA_FIELD) != 0) {
+	    unsigned len = (unsigned)get_byte();
+	    len |= ((unsigned)get_byte())<<8;
+	    while (len--) (void)get_byte();
+	}
+
+	/* Get original file name if it was truncated */
+	if ((flags & ORIG_NAME) != 0) {
+	    if (no_name || (to_stdout && !list) || part_nb > 1) {
+		/* Discard the old name */
+		char c; /* dummy used for NeXTstep 3.0 cc optimizer bug */
+		do {c=get_byte();} while (c != 0);
+	    } else {
+		/* Copy the base name. Keep a directory prefix intact. */
+                char *p = base_name (ofname);
+                char *base = p;
+		for (;;) {
+		    *p = (char)get_char();
+		    if (*p++ == '\0') break;
+		    if (p >= ofname+sizeof(ofname)) {
+			gzerror("corrupted input -- file name too large");
+		    }
+		}
+                /* If necessary, adapt the name to local OS conventions: */
+                if (!list) {
+                   MAKE_LEGAL_NAME(base);
+		   if (base) list=0; /* avoid warning about unused variable */
+                }
+	    } /* no_name || to_stdout */
+	} /* ORIG_NAME */
+
+	/* Discard file comment if any */
+	if ((flags & COMMENT) != 0) {
+	    while (get_char() != 0) /* null */ ;
+	}
+	if (part_nb == 1) {
+	    header_bytes = inptr + 2*sizeof(long); /* include crc and size */
+	}
+
+    } 
+    
+    if (method >= 0) return method;
+
+    if (part_nb == 1) {
+	fprintf(stderr, "\n%s: %s: not in gzip format\n", progname, ifname);
+	exit_code = ERROR;
+	return -1;
+    } else {
+	if (magic[0] == 0)
+	  {
+	    int inbyte;
+	    for (inbyte = imagic1;  inbyte == 0;  inbyte = try_byte ())
+	      continue;
+	    if (inbyte == EOF)
+	      {
+		return -3;
+	      }
+	  }
+
+	WARN((stderr, "\n%s: %s: decompression OK, trailing garbage ignored\n",
+	      progname, ifname));
+	return -2;
+    }
+}
+
+/* ========================================================================
+ * Free all dynamically allocated variables and exit with the given code.
+ */
+local void do_exit(exitcode)
+    int exitcode;
+{
+    static int in_exit = 0;
+
+    if (in_exit) exit(exitcode);
+    in_exit = 1;
+    if (env != NULL)  free(env),  env  = NULL;
+    if (args != NULL) free((char*)args), args = NULL;
+    FREE(inbuf);
+    FREE(outbuf);
+    FREE(d_buf);
+    FREE(window);
+#ifndef MAXSEG_64K
+    FREE(tab_prefix);
+#else
+    FREE(tab_prefix0);
+    FREE(tab_prefix1);
+#endif
+    exit(exitcode);
+}
+
+/* ========================================================================
+ * Signal and error handler.
+ */
+RETSIGTYPE abort_gzip()
+{
+   if (remove_ofname) {
+       close(ofd);
+       xunlink (ofname);
+   }
+   do_exit(ERROR);
+}
diff --git a/isys/gzlib/gzip.h b/isys/gzlib/gzip.h
new file mode 100644
index 000000000..7f8613866
--- /dev/null
+++ b/isys/gzlib/gzip.h
@@ -0,0 +1,315 @@
+/* gzip.h -- common declarations for all gzip modules
+ * Copyright (C) 1992-1993 Jean-loup Gailly.
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#if defined(__STDC__) || defined(PROTO)
+#  define OF(args)  args
+#else
+#  define OF(args)  ()
+#endif
+
+#ifdef __STDC__
+   typedef void *voidp;
+#else
+   typedef char *voidp;
+#endif
+
+/* I don't like nested includes, but the following headers are used
+ * too often
+ */
+#include <stdio.h>
+#include <sys/types.h> /* for off_t, time_t */
+#if defined HAVE_STRING_H || defined STDC_HEADERS
+#  include <string.h>
+#  if !defined STDC_HEADERS && defined HAVE_MEMORY_H && !defined __GNUC__
+#    include <memory.h>
+#  endif
+#  define memzero(s, n)     memset ((voidp)(s), 0, (n))
+#else
+#  include <strings.h>
+#  define strchr            index 
+#  define strrchr           rindex
+#  define memcpy(d, s, n)   bcopy((s), (d), (n)) 
+#  define memcmp(s1, s2, n) bcmp((s1), (s2), (n)) 
+#  define memzero(s, n)     bzero((s), (n))
+#endif
+
+#ifndef RETSIGTYPE
+#  define RETSIGTYPE void
+#endif
+
+#define local static
+
+typedef unsigned char  uch;
+typedef unsigned short ush;
+typedef unsigned long  ulg;
+
+/* Return codes from gzip */
+#define OK      0
+#define ERROR   1
+#define WARNING 2
+
+/* Compression methods (see algorithm.doc) */
+#define STORED      0
+#define COMPRESSED  1
+#define PACKED      2
+#define LZHED       3
+/* methods 4 to 7 reserved */
+#define DEFLATED    8
+#define MAX_METHODS 9
+extern int method;         /* compression method */
+
+/* To save memory for 16 bit systems, some arrays are overlaid between
+ * the various modules:
+ * deflate:  prev+head   window      d_buf  l_buf  outbuf
+ * unlzw:    tab_prefix  tab_suffix  stack  inbuf  outbuf
+ * inflate:              window             inbuf
+ * unpack:               window             inbuf  prefix_len
+ * unlzh:    left+right  window      c_table inbuf c_len
+ * For compression, input is done in window[]. For decompression, output
+ * is done in window except for unlzw.
+ */
+
+#ifndef	INBUFSIZ
+#  ifdef SMALL_MEM
+#    define INBUFSIZ  0x2000  /* input buffer size */
+#  else
+#    define INBUFSIZ  0x8000  /* input buffer size */
+#  endif
+#endif
+#define INBUF_EXTRA  64     /* required by unlzw() */
+
+#ifndef	OUTBUFSIZ
+#  ifdef SMALL_MEM
+#    define OUTBUFSIZ   8192  /* output buffer size */
+#  else
+#    define OUTBUFSIZ  16384  /* output buffer size */
+#  endif
+#endif
+#define OUTBUF_EXTRA 2048   /* required by unlzw() */
+
+#ifndef DIST_BUFSIZE
+#  ifdef SMALL_MEM
+#    define DIST_BUFSIZE 0x2000 /* buffer for distances, see trees.c */
+#  else
+#    define DIST_BUFSIZE 0x8000 /* buffer for distances, see trees.c */
+#  endif
+#endif
+
+#ifdef DYN_ALLOC
+#  define EXTERN(type, array)  extern type * near array
+#  define DECLARE(type, array, size)  type * near array
+#  define ALLOC(type, array, size) { \
+      array = (type*)fcalloc((size_t)(((size)+1L)/2), 2*sizeof(type)); \
+      if (array == NULL) gzerror("insufficient memory"); \
+   }
+#  define FREE(array) {if (array != NULL) fcfree(array), array=NULL;}
+#else
+#  define EXTERN(type, array)  extern type array[]
+#  define DECLARE(type, array, size)  type array[size]
+#  define ALLOC(type, array, size)
+#  define FREE(array)
+#endif
+
+EXTERN(uch, inbuf);          /* input buffer */
+EXTERN(uch, outbuf);         /* output buffer */
+EXTERN(ush, d_buf);          /* buffer for distances, see trees.c */
+EXTERN(uch, window);         /* Sliding window and suffix table (unlzw) */
+#define tab_suffix window
+#ifndef MAXSEG_64K
+#  define tab_prefix prev    /* hash link (see deflate.c) */
+#  define head (prev+WSIZE)  /* hash head (see deflate.c) */
+   EXTERN(ush, tab_prefix);  /* prefix code (see unlzw.c) */
+#else
+#  define tab_prefix0 prev
+#  define head tab_prefix1
+   EXTERN(ush, tab_prefix0); /* prefix for even codes */
+   EXTERN(ush, tab_prefix1); /* prefix for odd  codes */
+#endif
+
+extern unsigned insize; /* valid bytes in inbuf */
+extern unsigned inptr;  /* index of next byte to be processed in inbuf */
+extern unsigned outcnt; /* bytes in output buffer */
+
+extern off_t bytes_in;   /* number of input bytes */
+extern off_t bytes_out;  /* number of output bytes */
+extern off_t header_bytes;/* number of bytes in gzip header */
+
+extern int  ifd;        /* input file descriptor */
+extern int  ofd;        /* output file descriptor */
+extern char ifname[];   /* input file name or "stdin" */
+extern char ofname[];   /* output file name or "stdout" */
+extern char *progname;  /* program name */
+
+extern time_t time_stamp; /* original time stamp (modification time) */
+extern off_t ifile_size; /* input file size, -1 for devices (debug only) */
+
+typedef int file_t;     /* Do not use stdio */
+#define NO_FILE  (-1)   /* in memory compression */
+
+
+#define	PACK_MAGIC     "\037\036" /* Magic header for packed files */
+#define	GZIP_MAGIC     "\037\213" /* Magic header for gzip files, 1F 8B */
+#define	OLD_GZIP_MAGIC "\037\236" /* Magic header for gzip 0.5 = freeze 1.x */
+#define	LZH_MAGIC      "\037\240" /* Magic header for SCO LZH Compress files*/
+#define PKZIP_MAGIC    "\120\113\003\004" /* Magic header for pkzip files */
+
+/* gzip flag byte */
+#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
+#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
+#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define COMMENT      0x10 /* bit 4 set: file comment present */
+#define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
+#define RESERVED     0xC0 /* bit 6,7:   reserved */
+
+/* internal file attribute */
+#define UNKNOWN 0xffff
+#define BINARY  0
+#define ASCII   1
+
+#ifndef WSIZE
+#  define WSIZE 0x8000     /* window size--must be a power of two, and */
+#endif                     /*  at least 32K for zip's deflate method */
+
+#define MIN_MATCH  3
+#define MAX_MATCH  258
+/* The minimum and maximum match lengths */
+
+#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
+/* Minimum amount of lookahead, except at the end of the input file.
+ * See deflate.c for comments about the MIN_MATCH+1.
+ */
+
+#define MAX_DIST  (WSIZE-MIN_LOOKAHEAD)
+/* In order to simplify the code, particularly on 16 bit machines, match
+ * distances are limited to MAX_DIST instead of WSIZE.
+ */
+
+extern int decrypt;        /* flag to turn on decryption */
+extern int exit_code;      /* program exit code */
+extern int verbose;        /* be verbose (-v) */
+extern int quiet;          /* be quiet (-q) */
+extern int level;          /* compression level */
+extern int test;           /* check .z file integrity */
+extern int to_stdout;      /* output to stdout (-c) */
+extern int save_orig_name; /* set if original name must be saved */
+
+#define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf(0))
+#define try_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf(1))
+
+/* put_byte is used for the compressed output, put_ubyte for the
+ * uncompressed output. However unlzw() uses window for its
+ * suffix table instead of its output buffer, so it does not use put_ubyte
+ * (to be cleaned up).
+ */
+#define put_byte(c) {outbuf[outcnt++]=(uch)(c); if (outcnt==OUTBUFSIZ)\
+   flush_outbuf();}
+#define put_ubyte(c) {window[outcnt++]=(uch)(c); if (outcnt==WSIZE)\
+   flush_window();}
+
+/* Output a 16 bit value, lsb first */
+#define put_short(w) \
+{ if (outcnt < OUTBUFSIZ-2) { \
+    outbuf[outcnt++] = (uch) ((w) & 0xff); \
+    outbuf[outcnt++] = (uch) ((ush)(w) >> 8); \
+  } else { \
+    put_byte((uch)((w) & 0xff)); \
+    put_byte((uch)((ush)(w) >> 8)); \
+  } \
+}
+
+/* Output a 32 bit value to the bit stream, lsb first */
+#define put_long(n) { \
+    put_short((n) & 0xffff); \
+    put_short(((ulg)(n)) >> 16); \
+}
+
+#define seekable()    0  /* force sequential output */
+#define translate_eol 0  /* no option -a yet */
+
+#define tolow(c)  (isupper (c) ? tolower (c) : (c))  /* force to lower case */
+
+/* Macros for getting two-byte and four-byte header values */
+#define SH(p) ((ush)(uch)((p)[0]) | ((ush)(uch)((p)[1]) << 8))
+#define LG(p) ((ulg)(SH(p)) | ((ulg)(SH((p)+2)) << 16))
+
+/* Diagnostic functions */
+#ifdef DEBUG
+#  define Assert(cond,msg) {if(!(cond)) gzerror(msg);}
+#  define Trace(x) fprintf x
+#  define Tracev(x) {if (verbose) fprintf x ;}
+#  define Tracevv(x) {if (verbose>1) fprintf x ;}
+#  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
+#  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
+#else
+#  define Assert(cond,msg)
+#  define Trace(x)
+#  define Tracev(x)
+#  define Tracevv(x)
+#  define Tracec(c,x)
+#  define Tracecv(c,x)
+#endif
+
+#define WARN(msg) {if (!quiet) fprintf msg ; \
+		   if (exit_code == OK) exit_code = WARNING;}
+
+	/* in zip.c: */
+extern int zip        OF((int in, int out));
+extern int file_read  OF((char *buf,  unsigned size));
+
+	/* in unzip.c */
+extern int unzip      OF((int in, int out));
+extern int check_zipfile OF((int in));
+
+	/* in unpack.c */
+extern int unpack     OF((int in, int out));
+
+	/* in unlzh.c */
+extern int unlzh      OF((int in, int out));
+
+	/* in gzip.c */
+RETSIGTYPE abort_gzip OF((void));
+
+        /* in deflate.c */
+void lm_init OF((int pack_level, ush *flags));
+off_t deflate OF((void));
+
+        /* in trees.c */
+void ct_init     OF((ush *attr, int *method));
+int  ct_tally    OF((int dist, int lc));
+off_t flush_block OF((char *buf, ulg stored_len, int eof));
+
+        /* in bits.c */
+void     bi_init    OF((file_t zipfile));
+void     send_bits  OF((int value, int length));
+unsigned bi_reverse OF((unsigned value, int length));
+void     bi_windup  OF((void));
+void     copy_block OF((char *buf, unsigned len, int header));
+extern   int (*read_buf) OF((char *buf, unsigned size));
+
+	/* in util.c: */
+extern int copy           OF((int in, int out));
+extern ulg  updcrc        OF((uch *s, unsigned n));
+extern void clear_bufs    OF((void));
+extern int  fill_inbuf    OF((int eof_ok));
+extern void flush_outbuf  OF((void));
+extern void flush_window  OF((void));
+extern void write_buf     OF((int fd, voidp buf, unsigned cnt));
+extern char *strlwr       OF((char *s));
+extern char *base_name    OF((char *fname));
+extern int xunlink        OF((char *fname));
+extern void make_simple_name OF((char *name));
+extern char *add_envopt   OF((int *argcp, char ***argvp, char *env));
+extern void gzerror         OF((char *m));
+extern void warning       OF((char *m));
+extern void read_error    OF((void));
+extern void write_error   OF((void));
+extern void display_ratio OF((off_t num, off_t den, FILE *file));
+extern void fprint_off    OF((FILE *, off_t, int));
+extern voidp gzxmalloc      OF((unsigned int size));
+
+	/* in inflate.c */
+extern int inflate OF((void));
diff --git a/isys/gzlib/gzlib.h b/isys/gzlib/gzlib.h
new file mode 100644
index 000000000..5de4117d8
--- /dev/null
+++ b/isys/gzlib/gzlib.h
@@ -0,0 +1,10 @@
+#ifndef H_GZFILE
+#define H_GZFILE
+
+typedef struct gzFile_s * gzFile;
+
+gzFile gunzip_open(const char * file);
+int gunzip_read(gzFile str, void * buf, int bytes);
+int gunzip_close(gzFile str);
+
+#endif
diff --git a/isys/gzlib/inflate.c b/isys/gzlib/inflate.c
new file mode 100644
index 000000000..293aa1f34
--- /dev/null
+++ b/isys/gzlib/inflate.c
@@ -0,0 +1,957 @@
+/* inflate.c -- Not copyrighted 1992 by Mark Adler
+   version c10p1, 10 January 1993 */
+
+/* You can do whatever you like with this source file, though I would
+   prefer that if you modify it and redistribute it that you include
+   comments to that effect with your name and the date.  Thank you.
+   [The history has been moved to the file ChangeLog.]
+ */
+
+/*
+   Inflate deflated (PKZIP's method 8 compressed) data.  The compression
+   method searches for as much of the current string of bytes (up to a
+   length of 258) in the previous 32K bytes.  If it doesn't find any
+   matches (of at least length 3), it codes the next byte.  Otherwise, it
+   codes the length of the matched string and its distance backwards from
+   the current position.  There is a single Huffman code that codes both
+   single bytes (called "literals") and match lengths.  A second Huffman
+   code codes the distance information, which follows a length code.  Each
+   length or distance code actually represents a base value and a number
+   of "extra" (sometimes zero) bits to get to add to the base value.  At
+   the end of each deflated block is a special end-of-block (EOB) literal/
+   length code.  The decoding process is basically: get a literal/length
+   code; if EOB then done; if a literal, emit the decoded byte; if a
+   length then get the distance and emit the referred-to bytes from the
+   sliding window of previously emitted data.
+
+   There are (currently) three kinds of inflate blocks: stored, fixed, and
+   dynamic.  The compressor deals with some chunk of data at a time, and
+   decides which method to use on a chunk-by-chunk basis.  A chunk might
+   typically be 32K or 64K.  If the chunk is uncompressible, then the
+   "stored" method is used.  In this case, the bytes are simply stored as
+   is, eight bits per byte, with none of the above coding.  The bytes are
+   preceded by a count, since there is no longer an EOB code.
+
+   If the data is compressible, then either the fixed or dynamic methods
+   are used.  In the dynamic method, the compressed data is preceded by
+   an encoding of the literal/length and distance Huffman codes that are
+   to be used to decode this block.  The representation is itself Huffman
+   coded, and so is preceded by a description of that code.  These code
+   descriptions take up a little space, and so for small blocks, there is
+   a predefined set of codes, called the fixed codes.  The fixed method is
+   used if the block codes up smaller that way (usually for quite small
+   chunks), otherwise the dynamic method is used.  In the latter case, the
+   codes are customized to the probabilities in the current block, and so
+   can code it much better than the pre-determined fixed codes.
+ 
+   The Huffman codes themselves are decoded using a mutli-level table
+   lookup, in order to maximize the speed of decoding plus the speed of
+   building the decoding tables.  See the comments below that precede the
+   lbits and dbits tuning parameters.
+ */
+
+
+/*
+   Notes beyond the 1.93a appnote.txt:
+
+   1. Distance pointers never point before the beginning of the output
+      stream.
+   2. Distance pointers can point back across blocks, up to 32k away.
+   3. There is an implied maximum of 7 bits for the bit length table and
+      15 bits for the actual data.
+   4. If only one code exists, then it is encoded using one bit.  (Zero
+      would be more efficient, but perhaps a little confusing.)  If two
+      codes exist, they are coded using one bit each (0 and 1).
+   5. There is no way of sending zero distance codes--a dummy must be
+      sent if there are none.  (History: a pre 2.0 version of PKZIP would
+      store blocks with no distance codes, but this was discovered to be
+      too harsh a criterion.)  Valid only for 1.93a.  2.04c does allow
+      zero distance codes, which is sent as one code of zero bits in
+      length.
+   6. There are up to 286 literal/length codes.  Code 256 represents the
+      end-of-block.  Note however that the static length tree defines
+      288 codes just to fill out the Huffman codes.  Codes 286 and 287
+      cannot be used though, since there is no length base or extra bits
+      defined for them.  Similarly, there are up to 30 distance codes.
+      However, static trees define 32 codes (all 5 bits) to fill out the
+      Huffman codes, but the last two had better not show up in the data.
+   7. Unzip can check dynamic Huffman blocks for complete code sets.
+      The exception is that a single code would not be complete (see #4).
+   8. The five bits following the block type is really the number of
+      literal codes sent minus 257.
+   9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits
+      (1+6+6).  Therefore, to output three times the length, you output
+      three codes (1+1+1), whereas to output four times the same length,
+      you only need two codes (1+3).  Hmm.
+  10. In the tree reconstruction algorithm, Code = Code + Increment
+      only if BitLength(i) is not zero.  (Pretty obvious.)
+  11. Correction: 4 Bits: # of Bit Length codes - 4     (4 - 19)
+  12. Note: length code 284 can represent 227-258, but length code 285
+      really is 258.  The last length deserves its own, short code
+      since it gets used a lot in very redundant files.  The length
+      258 is special since 258 - 3 (the min match length) is 255.
+  13. The literal/length and distance code bit lengths are read as a
+      single stream of lengths.  It is possible (and advantageous) for
+      a repeat code (16, 17, or 18) to go across the boundary between
+      the two sets of lengths.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+#include <config.h>
+#include "tailor.h"
+
+#if defined STDC_HEADERS || defined HAVE_STDLIB_H
+#  include <stdlib.h>
+#endif
+
+#include "gzip.h"
+#define slide window
+
+/* Huffman code lookup table entry--this entry is four bytes for machines
+   that have 16-bit pointers (e.g. PC's in the small or medium model).
+   Valid extra bits are 0..13.  e == 15 is EOB (end of block), e == 16
+   means that v is a literal, 16 < e < 32 means that v is a pointer to
+   the next table, which codes e - 16 bits, and lastly e == 99 indicates
+   an unused code.  If a code with e == 99 is looked up, this implies an
+   error in the data. */
+struct huft {
+  uch e;                /* number of extra bits or operation */
+  uch b;                /* number of bits in this code or subcode */
+  union {
+    ush n;              /* literal, length base, or distance base */
+    struct huft *t;     /* pointer to next level of table */
+  } v;
+};
+
+
+/* Function prototypes */
+int huft_build OF((unsigned *, unsigned, unsigned, ush *, ush *,
+                   struct huft **, int *));
+int huft_free OF((struct huft *));
+int inflate_codes OF((struct huft *, struct huft *, int, int));
+int inflate_stored OF((void));
+int inflate_fixed OF((void));
+int inflate_dynamic OF((void));
+int inflate_block OF((int *));
+int inflate OF((void));
+
+
+/* The inflate algorithm uses a sliding 32K byte window on the uncompressed
+   stream to find repeated byte strings.  This is implemented here as a
+   circular buffer.  The index is updated simply by incrementing and then
+   and'ing with 0x7fff (32K-1). */
+/* It is left to other modules to supply the 32K area.  It is assumed
+   to be usable as if it were declared "uch slide[32768];" or as just
+   "uch *slide;" and then malloc'ed in the latter case.  The definition
+   must be in unzip.h, included above. */
+/* unsigned wp;             current position in slide */
+#define wp outcnt
+#define flush_output(w) (wp=(w),flush_window())
+
+/* Tables for deflate from PKZIP's appnote.txt. */
+static unsigned border[] = {    /* Order of the bit length code lengths */
+        16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+static ush cplens[] = {         /* Copy lengths for literal codes 257..285 */
+        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
+        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
+        /* note: see note #13 above about the 258 in this list. */
+static ush cplext[] = {         /* Extra bits for literal codes 257..285 */
+        0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
+        3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */
+static ush cpdist[] = {         /* Copy offsets for distance codes 0..29 */
+        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
+        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
+        8193, 12289, 16385, 24577};
+static ush cpdext[] = {         /* Extra bits for distance codes */
+        0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+        7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+        12, 12, 13, 13};
+
+
+
+/* Macros for inflate() bit peeking and grabbing.
+   The usage is:
+   
+        NEEDBITS(j)
+        x = b & mask_bits[j];
+        DUMPBITS(j)
+
+   where NEEDBITS makes sure that b has at least j bits in it, and
+   DUMPBITS removes the bits from b.  The macros use the variable k
+   for the number of bits in b.  Normally, b and k are register
+   variables for speed, and are initialized at the beginning of a
+   routine that uses these macros from a global bit buffer and count.
+
+   If we assume that EOB will be the longest code, then we will never
+   ask for bits with NEEDBITS that are beyond the end of the stream.
+   So, NEEDBITS should not read any more bytes than are needed to
+   meet the request.  Then no bytes need to be "returned" to the buffer
+   at the end of the last block.
+
+   However, this assumption is not true for fixed blocks--the EOB code
+   is 7 bits, but the other literal/length codes can be 8 or 9 bits.
+   (The EOB code is shorter than other codes because fixed blocks are
+   generally short.  So, while a block always has an EOB, many other
+   literal/length codes have a significantly lower probability of
+   showing up at all.)  However, by making the first table have a
+   lookup of seven bits, the EOB code will be found in that first
+   lookup, and so will not require that too many bits be pulled from
+   the stream.
+ */
+
+ulg bb;                         /* bit buffer */
+unsigned bk;                    /* bits in bit buffer */
+
+ush mask_bits[] = {
+    0x0000,
+    0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
+    0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
+};
+
+#ifdef CRYPT
+  uch cc;
+#  define NEXTBYTE() \
+     (decrypt ? (cc = get_byte(), zdecode(cc), cc) : get_byte())
+#else
+#  define NEXTBYTE()  (uch)get_byte()
+#endif
+#define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}}
+#define DUMPBITS(n) {b>>=(n);k-=(n);}
+
+
+/*
+   Huffman code decoding is performed using a multi-level table lookup.
+   The fastest way to decode is to simply build a lookup table whose
+   size is determined by the longest code.  However, the time it takes
+   to build this table can also be a factor if the data being decoded
+   is not very long.  The most common codes are necessarily the
+   shortest codes, so those codes dominate the decoding time, and hence
+   the speed.  The idea is you can have a shorter table that decodes the
+   shorter, more probable codes, and then point to subsidiary tables for
+   the longer codes.  The time it costs to decode the longer codes is
+   then traded against the time it takes to make longer tables.
+
+   This results of this trade are in the variables lbits and dbits
+   below.  lbits is the number of bits the first level table for literal/
+   length codes can decode in one step, and dbits is the same thing for
+   the distance codes.  Subsequent tables are also less than or equal to
+   those sizes.  These values may be adjusted either when all of the
+   codes are shorter than that, in which case the longest code length in
+   bits is used, or when the shortest code is *longer* than the requested
+   table size, in which case the length of the shortest code in bits is
+   used.
+
+   There are two different values for the two tables, since they code a
+   different number of possibilities each.  The literal/length table
+   codes 286 possible values, or in a flat code, a little over eight
+   bits.  The distance table codes 30 possible values, or a little less
+   than five bits, flat.  The optimum values for speed end up being
+   about one bit more than those, so lbits is 8+1 and dbits is 5+1.
+   The optimum values may differ though from machine to machine, and
+   possibly even between compilers.  Your mileage may vary.
+ */
+
+
+int lbits = 9;          /* bits in base literal/length lookup table */
+int dbits = 6;          /* bits in base distance lookup table */
+
+
+/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
+#define BMAX 16         /* maximum bit length of any code (16 for explode) */
+#define N_MAX 288       /* maximum number of codes in any set */
+
+
+unsigned hufts;         /* track memory usage */
+
+
+int huft_build(b, n, s, d, e, t, m)
+unsigned *b;            /* code lengths in bits (all assumed <= BMAX) */
+unsigned n;             /* number of codes (assumed <= N_MAX) */
+unsigned s;             /* number of simple-valued codes (0..s-1) */
+ush *d;                 /* list of base values for non-simple codes */
+ush *e;                 /* list of extra bits for non-simple codes */
+struct huft **t;        /* result: starting table */
+int *m;                 /* maximum lookup bits, returns actual */
+/* Given a list of code lengths and a maximum table size, make a set of
+   tables to decode that set of codes.  Return zero on success, one if
+   the given code set is incomplete (the tables are still built in this
+   case), two if the input is invalid (all zero length codes or an
+   oversubscribed set of lengths), and three if not enough memory. */
+{
+  unsigned a;                   /* counter for codes of length k */
+  unsigned c[BMAX+1];           /* bit length count table */
+  unsigned f;                   /* i repeats in table every f entries */
+  int g;                        /* maximum code length */
+  int h;                        /* table level */
+  register unsigned i;          /* counter, current code */
+  register unsigned j;          /* counter */
+  register int k;               /* number of bits in current code */
+  int l;                        /* bits per table (returned in m) */
+  register unsigned *p;         /* pointer into c[], b[], or v[] */
+  register struct huft *q;      /* points to current table */
+  struct huft r;                /* table entry for structure assignment */
+  struct huft *u[BMAX];         /* table stack */
+  unsigned v[N_MAX];            /* values in order of bit length */
+  register int w;               /* bits before this table == (l * h) */
+  unsigned x[BMAX+1];           /* bit offsets, then code stack */
+  unsigned *xp;                 /* pointer into x */
+  int y;                        /* number of dummy codes added */
+  unsigned z;                   /* number of entries in current table */
+
+
+  /* Generate counts for each bit length */
+  memzero(c, sizeof(c));
+  p = b;  i = n;
+  do {
+    Tracecv(*p, (stderr, (n-i >= ' ' && n-i <= '~' ? "%c %d\n" : "0x%x %d\n"), 
+	    n-i, *p));
+    c[*p]++;                    /* assume all entries <= BMAX */
+    p++;                      /* Can't combine with above line (Solaris bug) */
+  } while (--i);
+  if (c[0] == n)                /* null input--all zero length codes */
+  {
+    *t = (struct huft *)NULL;
+    *m = 0;
+    return 0;
+  }
+
+
+  /* Find minimum and maximum length, bound *m by those */
+  l = *m;
+  for (j = 1; j <= BMAX; j++)
+    if (c[j])
+      break;
+  k = j;                        /* minimum code length */
+  if ((unsigned)l < j)
+    l = j;
+  for (i = BMAX; i; i--)
+    if (c[i])
+      break;
+  g = i;                        /* maximum code length */
+  if ((unsigned)l > i)
+    l = i;
+  *m = l;
+
+
+  /* Adjust last length count to fill out codes, if needed */
+  for (y = 1 << j; j < i; j++, y <<= 1)
+    if ((y -= c[j]) < 0)
+      return 2;                 /* bad input: more codes than bits */
+  if ((y -= c[i]) < 0)
+    return 2;
+  c[i] += y;
+
+
+  /* Generate starting offsets into the value table for each length */
+  x[1] = j = 0;
+  p = c + 1;  xp = x + 2;
+  while (--i) {                 /* note that i == g from above */
+    *xp++ = (j += *p++);
+  }
+
+
+  /* Make a table of values in order of bit lengths */
+  p = b;  i = 0;
+  do {
+    if ((j = *p++) != 0)
+      v[x[j]++] = i;
+  } while (++i < n);
+  n = x[g];                   /* set n to length of v */
+
+
+  /* Generate the Huffman codes and for each, make the table entries */
+  x[0] = i = 0;                 /* first Huffman code is zero */
+  p = v;                        /* grab values in bit order */
+  h = -1;                       /* no tables yet--level -1 */
+  w = -l;                       /* bits decoded == (l * h) */
+  u[0] = (struct huft *)NULL;   /* just to keep compilers happy */
+  q = (struct huft *)NULL;      /* ditto */
+  z = 0;                        /* ditto */
+
+  /* go through the bit lengths (k already is bits in shortest code) */
+  for (; k <= g; k++)
+  {
+    a = c[k];
+    while (a--)
+    {
+      /* here i is the Huffman code of length k bits for value *p */
+      /* make tables up to required level */
+      while (k > w + l)
+      {
+        h++;
+        w += l;                 /* previous table always l bits */
+
+        /* compute minimum size table less than or equal to l bits */
+        z = (z = g - w) > (unsigned)l ? l : z;  /* upper limit on table size */
+        if ((f = 1 << (j = k - w)) > a + 1)     /* try a k-w bit table */
+        {                       /* too few codes for k-w bit table */
+          f -= a + 1;           /* deduct codes from patterns left */
+          xp = c + k;
+	  if (j < z)
+	    while (++j < z)       /* try smaller tables up to z bits */
+	    {
+	      if ((f <<= 1) <= *++xp)
+		break;            /* enough codes to use up j bits */
+	      f -= *xp;           /* else deduct codes from patterns */
+	    }
+        }
+        z = 1 << j;             /* table entries for j-bit table */
+
+        /* allocate and link in new table */
+        if ((q = (struct huft *)malloc((z + 1)*sizeof(struct huft))) ==
+            (struct huft *)NULL)
+        {
+          if (h)
+            huft_free(u[0]);
+          return 3;             /* not enough memory */
+        }
+        hufts += z + 1;         /* track memory usage */
+        *t = q + 1;             /* link to list for huft_free() */
+        *(t = &(q->v.t)) = (struct huft *)NULL;
+        u[h] = ++q;             /* table starts after link */
+
+        /* connect to last table, if there is one */
+        if (h)
+        {
+          x[h] = i;             /* save pattern for backing up */
+          r.b = (uch)l;         /* bits to dump before this table */
+          r.e = (uch)(16 + j);  /* bits in this table */
+          r.v.t = q;            /* pointer to this table */
+          j = i >> (w - l);     /* (get around Turbo C bug) */
+          u[h-1][j] = r;        /* connect to last table */
+        }
+      }
+
+      /* set up table entry in r */
+      r.b = (uch)(k - w);
+      if (p >= v + n)
+        r.e = 99;               /* out of values--invalid code */
+      else if (*p < s)
+      {
+        r.e = (uch)(*p < 256 ? 16 : 15);    /* 256 is end-of-block code */
+        r.v.n = (ush)(*p);             /* simple code is just the value */
+	p++;                           /* one compiler does not like *p++ */
+      }
+      else
+      {
+        r.e = (uch)e[*p - s];   /* non-simple--look up in lists */
+        r.v.n = d[*p++ - s];
+      }
+
+      /* fill code-like entries with r */
+      f = 1 << (k - w);
+      for (j = i >> w; j < z; j += f)
+        q[j] = r;
+
+      /* backwards increment the k-bit code i */
+      for (j = 1 << (k - 1); i & j; j >>= 1)
+        i ^= j;
+      i ^= j;
+
+      /* backup over finished tables */
+      while ((i & ((1 << w) - 1)) != x[h])
+      {
+        h--;                    /* don't need to update q */
+        w -= l;
+      }
+    }
+  }
+
+
+  /* Return true (1) if we were given an incomplete table */
+  return y != 0 && g != 1;
+}
+
+
+
+int huft_free(t)
+struct huft *t;         /* table to free */
+/* Free the malloc'ed tables built by huft_build(), which makes a linked
+   list of the tables it made, with the links in a dummy first entry of
+   each table. */
+{
+  register struct huft *p, *q;
+
+
+  /* Go through linked list, freeing from the malloced (t[-1]) address. */
+  p = t;
+  while (p != (struct huft *)NULL)
+  {
+    q = (--p)->v.t;
+    free((char*)p);
+    p = q;
+  } 
+  return 0;
+}
+
+
+int inflate_codes(tl, td, bl, bd)
+struct huft *tl, *td;   /* literal/length and distance decoder tables */
+int bl, bd;             /* number of bits decoded by tl[] and td[] */
+/* inflate (decompress) the codes in a deflated (compressed) block.
+   Return an error code or zero if it all goes ok. */
+{
+  register unsigned e;  /* table entry flag/number of extra bits */
+  unsigned n, d;        /* length and index for copy */
+  unsigned w;           /* current window position */
+  struct huft *t;       /* pointer to table entry */
+  unsigned ml, md;      /* masks for bl and bd bits */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local copies of globals */
+  b = bb;                       /* initialize bit buffer */
+  k = bk;
+  w = wp;                       /* initialize window position */
+
+  /* inflate the coded data */
+  ml = mask_bits[bl];           /* precompute masks for speed */
+  md = mask_bits[bd];
+  for (;;)                      /* do until end of block */
+  {
+    NEEDBITS((unsigned)bl)
+    if ((e = (t = tl + ((unsigned)b & ml))->e) > 16)
+      do {
+        if (e == 99)
+          return 1;
+        DUMPBITS(t->b)
+        e -= 16;
+        NEEDBITS(e)
+      } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
+    DUMPBITS(t->b)
+    if (e == 16)                /* then it's a literal */
+    {
+      slide[w++] = (uch)t->v.n;
+      Tracevv((stderr, "%c", slide[w-1]));
+      if (w == WSIZE)
+      {
+        flush_output(w);
+        w = 0;
+      }
+    }
+    else                        /* it's an EOB or a length */
+    {
+      /* exit if end of block */
+      if (e == 15)
+        break;
+
+      /* get length of block to copy */
+      NEEDBITS(e)
+      n = t->v.n + ((unsigned)b & mask_bits[e]);
+      DUMPBITS(e);
+
+      /* decode distance of block to copy */
+      NEEDBITS((unsigned)bd)
+      if ((e = (t = td + ((unsigned)b & md))->e) > 16)
+        do {
+          if (e == 99)
+            return 1;
+          DUMPBITS(t->b)
+          e -= 16;
+          NEEDBITS(e)
+        } while ((e = (t = t->v.t + ((unsigned)b & mask_bits[e]))->e) > 16);
+      DUMPBITS(t->b)
+      NEEDBITS(e)
+      d = w - t->v.n - ((unsigned)b & mask_bits[e]);
+      DUMPBITS(e)
+      Tracevv((stderr,"\\[%d,%d]", w-d, n));
+
+      /* do the copy */
+      do {
+        n -= (e = (e = WSIZE - ((d &= WSIZE-1) > w ? d : w)) > n ? n : e);
+#if !defined(NOMEMCPY) && !defined(DEBUG)
+        if (w - d >= e)         /* (this test assumes unsigned comparison) */
+        {
+          memcpy(slide + w, slide + d, e);
+          w += e;
+          d += e;
+        }
+        else                      /* do it slow to avoid memcpy() overlap */
+#endif /* !NOMEMCPY */
+          do {
+            slide[w++] = slide[d++];
+	    Tracevv((stderr, "%c", slide[w-1]));
+          } while (--e);
+        if (w == WSIZE)
+        {
+          flush_output(w);
+          w = 0;
+        }
+      } while (n);
+    }
+  }
+
+
+  /* restore the globals from the locals */
+  wp = w;                       /* restore global window pointer */
+  bb = b;                       /* restore global bit buffer */
+  bk = k;
+
+  /* done */
+  return 0;
+}
+
+
+
+int inflate_stored()
+/* "decompress" an inflated type 0 (stored) block. */
+{
+  unsigned n;           /* number of bytes in block */
+  unsigned w;           /* current window position */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local copies of globals */
+  b = bb;                       /* initialize bit buffer */
+  k = bk;
+  w = wp;                       /* initialize window position */
+
+
+  /* go to byte boundary */
+  n = k & 7;
+  DUMPBITS(n);
+
+
+  /* get the length and its complement */
+  NEEDBITS(16)
+  n = ((unsigned)b & 0xffff);
+  DUMPBITS(16)
+  NEEDBITS(16)
+  if (n != (unsigned)((~b) & 0xffff))
+    return 1;                   /* error in compressed data */
+  DUMPBITS(16)
+
+
+  /* read and output the compressed data */
+  while (n--)
+  {
+    NEEDBITS(8)
+    slide[w++] = (uch)b;
+    if (w == WSIZE)
+    {
+      flush_output(w);
+      w = 0;
+    }
+    DUMPBITS(8)
+  }
+
+
+  /* restore the globals from the locals */
+  wp = w;                       /* restore global window pointer */
+  bb = b;                       /* restore global bit buffer */
+  bk = k;
+  return 0;
+}
+
+
+
+int inflate_fixed()
+/* decompress an inflated type 1 (fixed Huffman codes) block.  We should
+   either replace this with a custom decoder, or at least precompute the
+   Huffman tables. */
+{
+  int i;                /* temporary variable */
+  struct huft *tl;      /* literal/length code table */
+  struct huft *td;      /* distance code table */
+  int bl;               /* lookup bits for tl */
+  int bd;               /* lookup bits for td */
+  unsigned l[288];      /* length list for huft_build */
+
+
+  /* set up literal table */
+  for (i = 0; i < 144; i++)
+    l[i] = 8;
+  for (; i < 256; i++)
+    l[i] = 9;
+  for (; i < 280; i++)
+    l[i] = 7;
+  for (; i < 288; i++)          /* make a complete, but wrong code set */
+    l[i] = 8;
+  bl = 7;
+  if ((i = huft_build(l, 288, 257, cplens, cplext, &tl, &bl)) != 0)
+    return i;
+
+
+  /* set up distance table */
+  for (i = 0; i < 30; i++)      /* make an incomplete code set */
+    l[i] = 5;
+  bd = 5;
+  if ((i = huft_build(l, 30, 0, cpdist, cpdext, &td, &bd)) > 1)
+  {
+    huft_free(tl);
+    return i;
+  }
+
+
+  /* decompress until an end-of-block code */
+  if (inflate_codes(tl, td, bl, bd))
+    return 1;
+
+
+  /* free the decoding tables, return */
+  huft_free(tl);
+  huft_free(td);
+  return 0;
+}
+
+
+
+int inflate_dynamic()
+/* decompress an inflated type 2 (dynamic Huffman codes) block. */
+{
+  int i;                /* temporary variables */
+  unsigned j;
+  unsigned l;           /* last length */
+  unsigned m;           /* mask for bit lengths table */
+  unsigned n;           /* number of lengths to get */
+  struct huft *tl;      /* literal/length code table */
+  struct huft *td;      /* distance code table */
+  int bl;               /* lookup bits for tl */
+  int bd;               /* lookup bits for td */
+  unsigned nb;          /* number of bit length codes */
+  unsigned nl;          /* number of literal/length codes */
+  unsigned nd;          /* number of distance codes */
+#ifdef PKZIP_BUG_WORKAROUND
+  unsigned ll[288+32];  /* literal/length and distance code lengths */
+#else
+  unsigned ll[286+30];  /* literal/length and distance code lengths */
+#endif
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local bit buffer */
+  b = bb;
+  k = bk;
+
+
+  /* read in table lengths */
+  NEEDBITS(5)
+  nl = 257 + ((unsigned)b & 0x1f);      /* number of literal/length codes */
+  DUMPBITS(5)
+  NEEDBITS(5)
+  nd = 1 + ((unsigned)b & 0x1f);        /* number of distance codes */
+  DUMPBITS(5)
+  NEEDBITS(4)
+  nb = 4 + ((unsigned)b & 0xf);         /* number of bit length codes */
+  DUMPBITS(4)
+#ifdef PKZIP_BUG_WORKAROUND
+  if (nl > 288 || nd > 32)
+#else
+  if (nl > 286 || nd > 30)
+#endif
+    return 1;                   /* bad lengths */
+
+
+  /* read in bit-length-code lengths */
+  for (j = 0; j < nb; j++)
+  {
+    NEEDBITS(3)
+    ll[border[j]] = (unsigned)b & 7;
+    DUMPBITS(3)
+  }
+  for (; j < 19; j++)
+    ll[border[j]] = 0;
+
+
+  /* build decoding table for trees--single level, 7 bit lookup */
+  bl = 7;
+  if ((i = huft_build(ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
+  {
+    if (i == 1)
+      huft_free(tl);
+    return i;                   /* incomplete code set */
+  }
+
+  if (tl == NULL)		/* Grrrhhh */
+	return 2;
+
+  /* read in literal and distance code lengths */
+  n = nl + nd;
+  m = mask_bits[bl];
+  i = l = 0;
+  while ((unsigned)i < n)
+  {
+    NEEDBITS((unsigned)bl)
+    j = (td = tl + ((unsigned)b & m))->b;
+    DUMPBITS(j)
+    j = td->v.n;
+    if (j < 16)                 /* length of code in bits (0..15) */
+      ll[i++] = l = j;          /* save last length in l */
+    else if (j == 16)           /* repeat last length 3 to 6 times */
+    {
+      NEEDBITS(2)
+      j = 3 + ((unsigned)b & 3);
+      DUMPBITS(2)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = l;
+    }
+    else if (j == 17)           /* 3 to 10 zero length codes */
+    {
+      NEEDBITS(3)
+      j = 3 + ((unsigned)b & 7);
+      DUMPBITS(3)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = 0;
+      l = 0;
+    }
+    else                        /* j == 18: 11 to 138 zero length codes */
+    {
+      NEEDBITS(7)
+      j = 11 + ((unsigned)b & 0x7f);
+      DUMPBITS(7)
+      if ((unsigned)i + j > n)
+        return 1;
+      while (j--)
+        ll[i++] = 0;
+      l = 0;
+    }
+  }
+
+
+  /* free decoding table for trees */
+  huft_free(tl);
+
+
+  /* restore the global bit buffer */
+  bb = b;
+  bk = k;
+
+
+  /* build the decoding tables for literal/length and distance codes */
+  bl = lbits;
+  if ((i = huft_build(ll, nl, 257, cplens, cplext, &tl, &bl)) != 0)
+  {
+    if (i == 1) {
+      fprintf(stderr, " incomplete literal tree\n");
+      huft_free(tl);
+    }
+    return i;                   /* incomplete code set */
+  }
+  bd = dbits;
+  if ((i = huft_build(ll + nl, nd, 0, cpdist, cpdext, &td, &bd)) != 0)
+  {
+    if (i == 1) {
+      fprintf(stderr, " incomplete distance tree\n");
+#ifdef PKZIP_BUG_WORKAROUND
+      i = 0;
+    }
+#else
+      huft_free(td);
+    }
+    huft_free(tl);
+    return i;                   /* incomplete code set */
+#endif
+  }
+
+
+  /* decompress until an end-of-block code */
+  if (inflate_codes(tl, td, bl, bd))
+    return 1;
+
+
+  /* free the decoding tables, return */
+  huft_free(tl);
+  huft_free(td);
+  return 0;
+}
+
+
+
+int inflate_block(e)
+int *e;                 /* last block flag */
+/* decompress an inflated block */
+{
+  unsigned t;           /* block type */
+  register ulg b;       /* bit buffer */
+  register unsigned k;  /* number of bits in bit buffer */
+
+
+  /* make local bit buffer */
+  b = bb;
+  k = bk;
+
+
+  /* read in last block bit */
+  NEEDBITS(1)
+  *e = (int)b & 1;
+  DUMPBITS(1)
+
+
+  /* read in block type */
+  NEEDBITS(2)
+  t = (unsigned)b & 3;
+  DUMPBITS(2)
+
+
+  /* restore the global bit buffer */
+  bb = b;
+  bk = k;
+
+
+  /* inflate that block type */
+  if (t == 2)
+    return inflate_dynamic();
+  if (t == 0)
+    return inflate_stored();
+  if (t == 1)
+    return inflate_fixed();
+
+
+  /* bad block type */
+  return 2;
+}
+
+
+
+int inflate()
+/* decompress an inflated entry */
+{
+  int e;                /* last block flag */
+  int r;                /* result code */
+  unsigned h;           /* maximum struct huft's malloc'ed */
+
+
+  /* initialize window, bit buffer */
+  wp = 0;
+  bk = 0;
+  bb = 0;
+
+
+  /* decompress until the last block */
+  h = 0;
+  do {
+    hufts = 0;
+    if ((r = inflate_block(&e)) != 0)
+      return r;
+    if (hufts > h)
+      h = hufts;
+  } while (!e);
+
+  /* Undo too much lookahead. The next read will be byte aligned so we
+   * can discard unused bits in the last meaningful byte.
+   */
+  while (bk >= 8) {
+    bk -= 8;
+    inptr--;
+  }
+
+  /* flush out slide */
+  flush_output(wp);
+
+
+  /* return success */
+#ifdef DEBUG
+  fprintf(stderr, "<%u> ", h);
+#endif /* DEBUG */
+  return 0;
+}
diff --git a/isys/gzlib/lzw.c b/isys/gzlib/lzw.c
new file mode 100644
index 000000000..0dc2fe063
--- /dev/null
+++ b/isys/gzlib/lzw.c
@@ -0,0 +1,27 @@
+/* lzw.c -- compress files in LZW format.
+ * This is a dummy version avoiding patent problems.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+#include <config.h>
+#include "tailor.h"
+#include "gzip.h"
+#include "lzw.h"
+
+static int msg_done = 0;
+
+/* Compress in to out with lzw method. */
+int lzw(in, out)
+    int in, out;
+{
+    if (msg_done) return ERROR;
+    msg_done = 1;
+    fprintf(stderr,"output in compress .Z format not supported\n");
+    if (in != out) { /* avoid warnings on unused variables */
+        exit_code = ERROR;
+    }
+    return ERROR;
+}
diff --git a/isys/gzlib/lzw.h b/isys/gzlib/lzw.h
new file mode 100644
index 000000000..4b7ac8680
--- /dev/null
+++ b/isys/gzlib/lzw.h
@@ -0,0 +1,42 @@
+/* lzw.h -- define the lzw functions.
+ * Copyright (C) 1992-1993 Jean-loup Gailly.
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#if !defined(OF) && defined(lint)
+#  include "gzip.h"
+#endif
+
+#ifndef BITS
+#  define BITS 16
+#endif
+#define INIT_BITS 9              /* Initial number of bits per code */
+
+#define	LZW_MAGIC  "\037\235"   /* Magic header for lzw files, 1F 9D */
+
+#define BIT_MASK    0x1f /* Mask for 'number of compression bits' */
+/* Mask 0x20 is reserved to mean a fourth header byte, and 0x40 is free.
+ * It's a pity that old uncompress does not check bit 0x20. That makes
+ * extension of the format actually undesirable because old compress
+ * would just crash on the new format instead of giving a meaningful
+ * error message. It does check the number of bits, but it's more
+ * helpful to say "unsupported format, get a new version" than
+ * "can only handle 16 bits".
+ */
+
+#define BLOCK_MODE  0x80
+/* Block compression: if table is full and compression rate is dropping,
+ * clear the dictionary.
+ */
+
+#define LZW_RESERVED 0x60 /* reserved bits */
+
+#define	CLEAR  256       /* flush the dictionary */
+#define FIRST  (CLEAR+1) /* first free entry */
+
+extern int maxbits;      /* max bits per code for LZW */
+extern int block_mode;   /* block compress mode -C compatible with 2.0 */
+
+extern int lzw    OF((int in, int out));
+extern int unlzw  OF((int in, int out));
diff --git a/isys/gzlib/tailor.h b/isys/gzlib/tailor.h
new file mode 100644
index 000000000..3e45e12c1
--- /dev/null
+++ b/isys/gzlib/tailor.h
@@ -0,0 +1,315 @@
+/* tailor.h -- target dependent definitions
+ * Copyright (C) 1992-1993 Jean-loup Gailly.
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+/* The target dependent definitions should be defined here only.
+ * The target dependent functions should be defined in tailor.c.
+ */
+
+/* $Id$ */
+
+#if defined(__MSDOS__) && !defined(MSDOS)
+#  define MSDOS
+#endif
+
+#if defined(__OS2__) && !defined(OS2)
+#  define OS2
+#endif
+
+#if defined(OS2) && defined(MSDOS) /* MS C under OS/2 */
+#  undef MSDOS
+#endif
+
+#ifdef MSDOS
+#  ifdef __GNUC__
+     /* DJGPP version 1.09+ on MS-DOS.
+      * The DJGPP 1.09 stat() function must be upgraded before gzip will
+      * fully work.
+      * No need for HAVE_DIRENT_H, since <unistd.h> defines POSIX_SOURCE which
+      * implies HAVE_DIRENT_H.
+      */
+#    define near
+#  else
+#    define MAXSEG_64K
+#    ifdef __TURBOC__
+#      define off_t long
+#      ifdef __BORLANDC__
+#        define HAVE_DIRENT_H
+#        define HAVE_UTIME
+#      endif
+#      define HAVE_UTIME_H
+#    else /* MSC */
+#      define HAVE_SYS_UTIME_H
+#    endif
+#  endif
+#  define PATH_SEP2 '\\'
+#  define PATH_SEP3 ':'
+#  define MAX_PATH_LEN  128
+#  define NO_MULTIPLE_DOTS
+#  define MAX_EXT_CHARS 3
+#  define Z_SUFFIX "z"
+#  define PROTO
+#  define STDC_HEADERS
+#  define NO_SIZE_CHECK
+#  define UNLINK_READONLY_BUG
+#  define casemap(c) tolow(c) /* Force file names to lower case */
+#  include <io.h>
+#  define OS_CODE  0x00
+#  define SET_BINARY_MODE(fd) setmode(fd, O_BINARY)
+#  if !defined(NO_ASM) && !defined(ASMV)
+#    define ASMV
+#  endif
+#else
+#  define near
+#endif
+
+#ifdef OS2
+#  define PATH_SEP2 '\\'
+#  define PATH_SEP3 ':'
+#  define MAX_PATH_LEN  260
+#  ifdef OS2FAT
+#    define NO_MULTIPLE_DOTS
+#    define MAX_EXT_CHARS 3
+#    define Z_SUFFIX "z"
+#    define casemap(c) tolow(c)
+#  endif
+#  define PROTO
+#  define STDC_HEADERS
+#  define UNLINK_READONLY_BUG
+#  include <io.h>
+#  define OS_CODE  0x06
+#  define SET_BINARY_MODE(fd) setmode(fd, O_BINARY)
+#  ifdef _MSC_VER
+#    define HAVE_SYS_UTIME_H
+#    define MAXSEG_64K
+#    undef near
+#    define near _near
+#  endif
+#  ifdef __EMX__
+#    define HAVE_SYS_UTIME_H
+#    define HAVE_DIRENT_H
+#    define EXPAND(argc,argv) \
+       {_response(&argc, &argv); _wildcard(&argc, &argv);}
+#  endif
+#  ifdef __BORLANDC__
+#    define HAVE_DIRENT_H
+#    define HAVE_UTIME_H
+#  endif
+#  ifdef __ZTC__
+#    define NO_DIR
+#    include <dos.h>
+#    define EXPAND(argc,argv) \
+       {response_expand(&argc, &argv);}
+#  endif
+#endif
+
+#ifdef WIN32 /* Windows NT */
+#  define HAVE_SYS_UTIME_H
+#  define PATH_SEP2 '\\'
+#  define PATH_SEP3 ':'
+#  define MAX_PATH_LEN  260
+#  define PROTO
+#  define STDC_HEADERS
+#  define SET_BINARY_MODE(fd) setmode(fd, O_BINARY)
+#  define UNLINK_READONLY_BUG
+#  include <io.h>
+#  include <malloc.h>
+#  ifdef NTFAT
+#    define NO_MULTIPLE_DOTS
+#    define MAX_EXT_CHARS 3
+#    define Z_SUFFIX "z"
+#    define casemap(c) tolow(c) /* Force file names to lower case */
+#  endif
+#  define OS_CODE  0x0b
+#endif
+
+#ifdef MSDOS
+#  ifdef __TURBOC__
+#    include <alloc.h>
+#    define DYN_ALLOC
+     /* Turbo C 2.0 does not accept static allocations of large arrays */
+     void * fcalloc (unsigned items, unsigned size);
+     void fcfree (void *ptr);
+#  else /* MSC */
+#    include <malloc.h>
+#    define fcalloc(nitems,itemsize) halloc((long)(nitems),(itemsize))
+#    define fcfree(ptr) hfree(ptr)
+#  endif
+#else
+#  ifdef MAXSEG_64K
+#    define fcalloc(items,size) calloc((items),(size))
+#  else
+#    define fcalloc(items,size) malloc((size_t)(items)*(size_t)(size))
+#  endif
+#  define fcfree(ptr) free(ptr)
+#endif
+
+#if defined(VAXC) || defined(VMS)
+#  define PATH_SEP ']'
+#  define PATH_SEP2 ':'
+#  define SUFFIX_SEP ';'
+#  define NO_MULTIPLE_DOTS
+#  define Z_SUFFIX "-gz"
+#  define RECORD_IO 1
+#  define casemap(c) tolow(c)
+#  define OS_CODE  0x02
+#  define OPTIONS_VAR "GZIP_OPT"
+#  define STDC_HEADERS
+#  define EXPAND(argc,argv) vms_expand_args(&argc,&argv);
+#  include <file.h>
+#  define unlink delete
+#  ifdef VAXC
+#    include <unixio.h>
+#  else
+#    define HAVE_FCNTL_H
+#  endif
+#endif
+
+#ifdef AMIGA
+#  define PATH_SEP2 ':'
+#  define STDC_HEADERS
+#  define OS_CODE  0x01
+#  define ASMV
+#  ifdef __GNUC__
+#    define HAVE_DIRENT_H
+#    define HAVE_FCNTL_H
+#    define HAVE_UNISTD_H
+#    define HAVE_CHOWN
+#    define HAVE_LSTAT
+#  else /* SASC */
+#    define NO_STDIN_FSTAT
+#    define HAVE_SYS_DIR_H
+#    include <fcntl.h> /* for read() and write() */
+#    define direct dirent
+     extern void _expand_args(int *argc, char ***argv);
+#    define EXPAND(argc,argv) _expand_args(&argc,&argv);
+#    undef  O_BINARY /* disable useless --ascii option */
+#  endif
+#endif
+
+#if defined(ATARI) || defined(atarist)
+#  ifndef STDC_HEADERS
+#    define STDC_HEADERS
+#    define HAVE_UNISTD_H
+#    define HAVE_DIRENT_H
+#  endif
+#  define ASMV
+#  define OS_CODE  0x05
+#  ifdef TOSFS
+#    define PATH_SEP2 '\\'
+#    define PATH_SEP3 ':'
+#    define MAX_PATH_LEN  128
+#    define NO_MULTIPLE_DOTS
+#    define MAX_EXT_CHARS 3
+#    define Z_SUFFIX "z"
+#    define casemap(c) tolow(c) /* Force file names to lower case */
+#  endif
+#endif
+
+#ifdef MACOS
+#  define PATH_SEP ':'
+#  define DYN_ALLOC
+#  define PROTO
+#  define NO_STDIN_FSTAT
+#  define chmod(file, mode) (0)
+#  define OPEN(name, flags, mode) open(name, flags)
+#  define OS_CODE  0x07
+#  ifdef MPW
+#    define isatty(fd) ((fd) <= 2)
+#  endif
+#endif
+
+#ifdef __50SERIES /* Prime/PRIMOS */
+#  define PATH_SEP '>'
+#  define STDC_HEADERS
+#  define NO_STDIN_FSTAT 
+#  define NO_SIZE_CHECK 
+#  define RECORD_IO  1
+#  define casemap(c)  tolow(c) /* Force file names to lower case */
+#  define put_char(c) put_byte((c) & 0x7F)
+#  define get_char(c) ascii2pascii(get_byte())
+#  define OS_CODE  0x0F    /* temporary, subject to change */
+#  ifdef SIGTERM
+#    undef SIGTERM         /* We don't want a signal handler for SIGTERM */
+#  endif
+#endif
+
+#if defined(pyr) && !defined(NOMEMCPY) /* Pyramid */
+#  define NOMEMCPY /* problem with overlapping copies */
+#endif
+
+#ifdef TOPS20
+#  define OS_CODE  0x0a
+#endif
+
+#ifndef unix
+#  define NO_ST_INO /* don't rely on inode numbers */
+#endif
+
+
+	/* Common defaults */
+
+#ifndef OS_CODE
+#  define OS_CODE  0x03  /* assume Unix */
+#endif
+
+#ifndef PATH_SEP
+#  define PATH_SEP '/'
+#endif
+
+#ifndef casemap
+#  define casemap(c) (c)
+#endif
+
+#ifndef OPTIONS_VAR
+#  define OPTIONS_VAR "GZIP"
+#endif
+
+#ifndef Z_SUFFIX
+#  define Z_SUFFIX ".gz"
+#endif
+
+#ifdef MAX_EXT_CHARS
+#  define MAX_SUFFIX  MAX_EXT_CHARS
+#else
+#  define MAX_SUFFIX  30
+#endif
+
+#ifndef MAKE_LEGAL_NAME
+#  ifdef NO_MULTIPLE_DOTS
+#    define MAKE_LEGAL_NAME(name)   make_simple_name(name)
+#  else
+#    define MAKE_LEGAL_NAME(name)
+#  endif
+#endif
+
+#ifndef MIN_PART
+#  define MIN_PART 3
+   /* keep at least MIN_PART chars between dots in a file name. */
+#endif
+
+#ifndef EXPAND
+#  define EXPAND(argc,argv)
+#endif
+
+#ifndef RECORD_IO
+#  define RECORD_IO 0
+#endif
+
+#ifndef SET_BINARY_MODE
+#  define SET_BINARY_MODE(fd)
+#endif
+
+#ifndef OPEN
+#  define OPEN(name, flags, mode) open(name, flags, mode)
+#endif
+
+#ifndef get_char
+#  define get_char() get_byte()
+#endif
+
+#ifndef put_char
+#  define put_char(c) put_byte(c)
+#endif
diff --git a/isys/gzlib/trees.c b/isys/gzlib/trees.c
new file mode 100644
index 000000000..71659a5ac
--- /dev/null
+++ b/isys/gzlib/trees.c
@@ -0,0 +1,1069 @@
+/* trees.c -- output deflated data using Huffman coding
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+/*
+ *  PURPOSE
+ *
+ *      Encode various sets of source values using variable-length
+ *      binary code trees.
+ *
+ *  DISCUSSION
+ *
+ *      The PKZIP "deflation" process uses several Huffman trees. The more
+ *      common source values are represented by shorter bit sequences.
+ *
+ *      Each code tree is stored in the ZIP file in a compressed form
+ *      which is itself a Huffman encoding of the lengths of
+ *      all the code strings (in ascending order by source values).
+ *      The actual code strings are reconstructed from the lengths in
+ *      the UNZIP process, as described in the "application note"
+ *      (APPNOTE.TXT) distributed as part of PKWARE's PKZIP program.
+ *
+ *  REFERENCES
+ *
+ *      Lynch, Thomas J.
+ *          Data Compression:  Techniques and Applications, pp. 53-55.
+ *          Lifetime Learning Publications, 1985.  ISBN 0-534-03418-7.
+ *
+ *      Storer, James A.
+ *          Data Compression:  Methods and Theory, pp. 49-50.
+ *          Computer Science Press, 1988.  ISBN 0-7167-8156-5.
+ *
+ *      Sedgewick, R.
+ *          Algorithms, p290.
+ *          Addison-Wesley, 1983. ISBN 0-201-06672-6.
+ *
+ *  INTERFACE
+ *
+ *      void ct_init (ush *attr, int *methodp)
+ *          Allocate the match buffer, initialize the various tables and save
+ *          the location of the internal file attribute (ascii/binary) and
+ *          method (DEFLATE/STORE)
+ *
+ *      void ct_tally (int dist, int lc);
+ *          Save the match info and tally the frequency counts.
+ *
+ *      off_t flush_block (char *buf, ulg stored_len, int eof)
+ *          Determine the best encoding for the current block: dynamic trees,
+ *          static trees or store, and output the encoded block to the zip
+ *          file. Returns the total compressed length for the file so far.
+ *
+ */
+
+#include <config.h>
+#include <ctype.h>
+
+#include "tailor.h"
+#include "gzip.h"
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+/* ===========================================================================
+ * Constants
+ */
+
+#define MAX_BITS 15
+/* All codes must not exceed MAX_BITS bits */
+
+#define MAX_BL_BITS 7
+/* Bit length codes must not exceed MAX_BL_BITS bits */
+
+#define LENGTH_CODES 29
+/* number of length codes, not counting the special END_BLOCK code */
+
+#define LITERALS  256
+/* number of literal bytes 0..255 */
+
+#define END_BLOCK 256
+/* end of block literal code */
+
+#define L_CODES (LITERALS+1+LENGTH_CODES)
+/* number of Literal or Length codes, including the END_BLOCK code */
+
+#define D_CODES   30
+/* number of distance codes */
+
+#define BL_CODES  19
+/* number of codes used to transfer the bit lengths */
+
+
+local int near extra_lbits[LENGTH_CODES] /* extra bits for each length code */
+   = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};
+
+local int near extra_dbits[D_CODES] /* extra bits for each distance code */
+   = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
+
+local int near extra_blbits[BL_CODES]/* extra bits for each bit length code */
+   = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};
+
+#define STORED_BLOCK 0
+#define STATIC_TREES 1
+#define DYN_TREES    2
+/* The three kinds of block type */
+
+#ifndef LIT_BUFSIZE
+#  ifdef SMALL_MEM
+#    define LIT_BUFSIZE  0x2000
+#  else
+#  ifdef MEDIUM_MEM
+#    define LIT_BUFSIZE  0x4000
+#  else
+#    define LIT_BUFSIZE  0x8000
+#  endif
+#  endif
+#endif
+#ifndef DIST_BUFSIZE
+#  define DIST_BUFSIZE  LIT_BUFSIZE
+#endif
+/* Sizes of match buffers for literals/lengths and distances.  There are
+ * 4 reasons for limiting LIT_BUFSIZE to 64K:
+ *   - frequencies can be kept in 16 bit counters
+ *   - if compression is not successful for the first block, all input data is
+ *     still in the window so we can still emit a stored block even when input
+ *     comes from standard input.  (This can also be done for all blocks if
+ *     LIT_BUFSIZE is not greater than 32K.)
+ *   - if compression is not successful for a file smaller than 64K, we can
+ *     even emit a stored file instead of a stored block (saving 5 bytes).
+ *   - creating new Huffman trees less frequently may not provide fast
+ *     adaptation to changes in the input data statistics. (Take for
+ *     example a binary file with poorly compressible code followed by
+ *     a highly compressible string table.) Smaller buffer sizes give
+ *     fast adaptation but have of course the overhead of transmitting trees
+ *     more frequently.
+ *   - I can't count above 4
+ * The current code is general and allows DIST_BUFSIZE < LIT_BUFSIZE (to save
+ * memory at the expense of compression). Some optimizations would be possible
+ * if we rely on DIST_BUFSIZE == LIT_BUFSIZE.
+ */
+#if LIT_BUFSIZE > INBUFSIZ
+    error cannot overlay l_buf and inbuf
+#endif
+
+#define REP_3_6      16
+/* repeat previous bit length 3-6 times (2 bits of repeat count) */
+
+#define REPZ_3_10    17
+/* repeat a zero length 3-10 times  (3 bits of repeat count) */
+
+#define REPZ_11_138  18
+/* repeat a zero length 11-138 times  (7 bits of repeat count) */
+
+/* ===========================================================================
+ * Local data
+ */
+
+/* Data structure describing a single value and its code string. */
+typedef struct ct_data {
+    union {
+        ush  freq;       /* frequency count */
+        ush  code;       /* bit string */
+    } fc;
+    union {
+        ush  dad;        /* father node in Huffman tree */
+        ush  len;        /* length of bit string */
+    } dl;
+} ct_data;
+
+#define Freq fc.freq
+#define Code fc.code
+#define Dad  dl.dad
+#define Len  dl.len
+
+#define HEAP_SIZE (2*L_CODES+1)
+/* maximum heap size */
+
+local ct_data near dyn_ltree[HEAP_SIZE];   /* literal and length tree */
+local ct_data near dyn_dtree[2*D_CODES+1]; /* distance tree */
+
+local ct_data near static_ltree[L_CODES+2];
+/* The static literal tree. Since the bit lengths are imposed, there is no
+ * need for the L_CODES extra codes used during heap construction. However
+ * The codes 286 and 287 are needed to build a canonical tree (see ct_init
+ * below).
+ */
+
+local ct_data near static_dtree[D_CODES];
+/* The static distance tree. (Actually a trivial tree since all codes use
+ * 5 bits.)
+ */
+
+local ct_data near bl_tree[2*BL_CODES+1];
+/* Huffman tree for the bit lengths */
+
+typedef struct tree_desc {
+    ct_data near *dyn_tree;      /* the dynamic tree */
+    ct_data near *static_tree;   /* corresponding static tree or NULL */
+    int     near *extra_bits;    /* extra bits for each code or NULL */
+    int     extra_base;          /* base index for extra_bits */
+    int     elems;               /* max number of elements in the tree */
+    int     max_length;          /* max bit length for the codes */
+    int     max_code;            /* largest code with non zero frequency */
+} tree_desc;
+
+local tree_desc near l_desc =
+{dyn_ltree, static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS, 0};
+
+local tree_desc near d_desc =
+{dyn_dtree, static_dtree, extra_dbits, 0,          D_CODES, MAX_BITS, 0};
+
+local tree_desc near bl_desc =
+{bl_tree, (ct_data near *)0, extra_blbits, 0,      BL_CODES, MAX_BL_BITS, 0};
+
+
+local ush near bl_count[MAX_BITS+1];
+/* number of codes at each bit length for an optimal tree */
+
+local uch near bl_order[BL_CODES]
+   = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};
+/* The lengths of the bit length codes are sent in order of decreasing
+ * probability, to avoid transmitting the lengths for unused bit length codes.
+ */
+
+local int near heap[2*L_CODES+1]; /* heap used to build the Huffman trees */
+local int heap_len;               /* number of elements in the heap */
+local int heap_max;               /* element of largest frequency */
+/* The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
+ * The same heap array is used to build all trees.
+ */
+
+local uch near depth[2*L_CODES+1];
+/* Depth of each subtree used as tie breaker for trees of equal frequency */
+
+local uch length_code[MAX_MATCH-MIN_MATCH+1];
+/* length code for each normalized match length (0 == MIN_MATCH) */
+
+local uch dist_code[512];
+/* distance codes. The first 256 values correspond to the distances
+ * 3 .. 258, the last 256 values correspond to the top 8 bits of
+ * the 15 bit distances.
+ */
+
+local int near base_length[LENGTH_CODES];
+/* First normalized length for each code (0 = MIN_MATCH) */
+
+local int near base_dist[D_CODES];
+/* First normalized distance for each code (0 = distance of 1) */
+
+#define l_buf inbuf
+/* DECLARE(uch, l_buf, LIT_BUFSIZE);  buffer for literals or lengths */
+
+/* DECLARE(ush, d_buf, DIST_BUFSIZE); buffer for distances */
+
+local uch near flag_buf[(LIT_BUFSIZE/8)];
+/* flag_buf is a bit array distinguishing literals from lengths in
+ * l_buf, thus indicating the presence or absence of a distance.
+ */
+
+local unsigned last_lit;    /* running index in l_buf */
+local unsigned last_dist;   /* running index in d_buf */
+local unsigned last_flags;  /* running index in flag_buf */
+local uch flags;            /* current flags not yet saved in flag_buf */
+local uch flag_bit;         /* current bit used in flags */
+/* bits are filled in flags starting at bit 0 (least significant).
+ * Note: these flags are overkill in the current code since we don't
+ * take advantage of DIST_BUFSIZE == LIT_BUFSIZE.
+ */
+
+local ulg opt_len;        /* bit length of current block with optimal trees */
+local ulg static_len;     /* bit length of current block with static trees */
+
+local off_t compressed_len; /* total bit length of compressed file */
+
+local off_t input_len;      /* total byte length of input file */
+/* input_len is for debugging only since we can get it by other means. */
+
+ush *file_type;        /* pointer to UNKNOWN, BINARY or ASCII */
+int *file_method;      /* pointer to DEFLATE or STORE */
+
+#ifdef DEBUG
+extern off_t bits_sent;  /* bit length of the compressed data */
+#endif
+
+extern long block_start;       /* window offset of current block */
+extern unsigned near strstart; /* window offset of current string */
+
+/* ===========================================================================
+ * Local (static) routines in this file.
+ */
+
+local void init_block     OF((void));
+local void pqdownheap     OF((ct_data near *tree, int k));
+local void gen_bitlen     OF((tree_desc near *desc));
+local void gen_codes      OF((ct_data near *tree, int max_code));
+local void build_tree     OF((tree_desc near *desc));
+local void scan_tree      OF((ct_data near *tree, int max_code));
+local void send_tree      OF((ct_data near *tree, int max_code));
+local int  build_bl_tree  OF((void));
+local void send_all_trees OF((int lcodes, int dcodes, int blcodes));
+local void compress_block OF((ct_data near *ltree, ct_data near *dtree));
+local void set_file_type  OF((void));
+
+
+#ifndef DEBUG
+#  define send_code(c, tree) send_bits(tree[c].Code, tree[c].Len)
+   /* Send a code of the given tree. c and tree must not have side effects */
+
+#else /* DEBUG */
+#  define send_code(c, tree) \
+     { send_bits(tree[c].Code, tree[c].Len); }
+#endif
+
+#define d_code(dist) \
+   ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)])
+/* Mapping from a distance to a distance code. dist is the distance - 1 and
+ * must not have side effects. dist_code[256] and dist_code[257] are never
+ * used.
+ */
+
+#define MAX(a,b) (a >= b ? a : b)
+/* the arguments must not have side effects */
+
+/* ===========================================================================
+ * Allocate the match buffer, initialize the various tables and save the
+ * location of the internal file attribute (ascii/binary) and method
+ * (DEFLATE/STORE).
+ */
+void ct_init(attr, methodp)
+    ush  *attr;   /* pointer to internal file attribute */
+    int  *methodp; /* pointer to compression method */
+{
+    int n;        /* iterates over tree elements */
+    int bits;     /* bit counter */
+    int length;   /* length value */
+    int code;     /* code value */
+    int dist;     /* distance index */
+
+    file_type = attr;
+    file_method = methodp;
+    compressed_len = input_len = 0L;
+        
+    if (static_dtree[0].Len != 0) return; /* ct_init already called */
+
+    /* Initialize the mapping length (0..255) -> length code (0..28) */
+    length = 0;
+    for (code = 0; code < LENGTH_CODES-1; code++) {
+        base_length[code] = length;
+        for (n = 0; n < (1<<extra_lbits[code]); n++) {
+            length_code[length++] = (uch)code;
+        }
+    }
+    Assert (length == 256, "ct_init: length != 256");
+    /* Note that the length 255 (match length 258) can be represented
+     * in two different ways: code 284 + 5 bits or code 285, so we
+     * overwrite length_code[255] to use the best encoding:
+     */
+    length_code[length-1] = (uch)code;
+
+    /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
+    dist = 0;
+    for (code = 0 ; code < 16; code++) {
+        base_dist[code] = dist;
+        for (n = 0; n < (1<<extra_dbits[code]); n++) {
+            dist_code[dist++] = (uch)code;
+        }
+    }
+    Assert (dist == 256, "ct_init: dist != 256");
+    dist >>= 7; /* from now on, all distances are divided by 128 */
+    for ( ; code < D_CODES; code++) {
+        base_dist[code] = dist << 7;
+        for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {
+            dist_code[256 + dist++] = (uch)code;
+        }
+    }
+    Assert (dist == 256, "ct_init: 256+dist != 512");
+
+    /* Construct the codes of the static literal tree */
+    for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
+    n = 0;
+    while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;
+    while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;
+    while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;
+    while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;
+    /* Codes 286 and 287 do not exist, but we must include them in the
+     * tree construction to get a canonical Huffman tree (longest code
+     * all ones)
+     */
+    gen_codes((ct_data near *)static_ltree, L_CODES+1);
+
+    /* The static distance tree is trivial: */
+    for (n = 0; n < D_CODES; n++) {
+        static_dtree[n].Len = 5;
+        static_dtree[n].Code = bi_reverse(n, 5);
+    }
+
+    /* Initialize the first block of the first file: */
+    init_block();
+}
+
+/* ===========================================================================
+ * Initialize a new block.
+ */
+local void init_block()
+{
+    int n; /* iterates over tree elements */
+
+    /* Initialize the trees. */
+    for (n = 0; n < L_CODES;  n++) dyn_ltree[n].Freq = 0;
+    for (n = 0; n < D_CODES;  n++) dyn_dtree[n].Freq = 0;
+    for (n = 0; n < BL_CODES; n++) bl_tree[n].Freq = 0;
+
+    dyn_ltree[END_BLOCK].Freq = 1;
+    opt_len = static_len = 0L;
+    last_lit = last_dist = last_flags = 0;
+    flags = 0; flag_bit = 1;
+}
+
+#define SMALLEST 1
+/* Index within the heap array of least frequent node in the Huffman tree */
+
+
+/* ===========================================================================
+ * Remove the smallest element from the heap and recreate the heap with
+ * one less element. Updates heap and heap_len.
+ */
+#define pqremove(tree, top) \
+{\
+    top = heap[SMALLEST]; \
+    heap[SMALLEST] = heap[heap_len--]; \
+    pqdownheap(tree, SMALLEST); \
+}
+
+/* ===========================================================================
+ * Compares to subtrees, using the tree depth as tie breaker when
+ * the subtrees have equal frequency. This minimizes the worst case length.
+ */
+#define smaller(tree, n, m) \
+   (tree[n].Freq < tree[m].Freq || \
+   (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m]))
+
+/* ===========================================================================
+ * Restore the heap property by moving down the tree starting at node k,
+ * exchanging a node with the smallest of its two sons if necessary, stopping
+ * when the heap property is re-established (each father smaller than its
+ * two sons).
+ */
+local void pqdownheap(tree, k)
+    ct_data near *tree;  /* the tree to restore */
+    int k;               /* node to move down */
+{
+    int v = heap[k];
+    int j = k << 1;  /* left son of k */
+    while (j <= heap_len) {
+        /* Set j to the smallest of the two sons: */
+        if (j < heap_len && smaller(tree, heap[j+1], heap[j])) j++;
+
+        /* Exit if v is smaller than both sons */
+        if (smaller(tree, v, heap[j])) break;
+
+        /* Exchange v with the smallest son */
+        heap[k] = heap[j];  k = j;
+
+        /* And continue down the tree, setting j to the left son of k */
+        j <<= 1;
+    }
+    heap[k] = v;
+}
+
+/* ===========================================================================
+ * Compute the optimal bit lengths for a tree and update the total bit length
+ * for the current block.
+ * IN assertion: the fields freq and dad are set, heap[heap_max] and
+ *    above are the tree nodes sorted by increasing frequency.
+ * OUT assertions: the field len is set to the optimal bit length, the
+ *     array bl_count contains the frequencies for each bit length.
+ *     The length opt_len is updated; static_len is also updated if stree is
+ *     not null.
+ */
+local void gen_bitlen(desc)
+    tree_desc near *desc; /* the tree descriptor */
+{
+    ct_data near *tree  = desc->dyn_tree;
+    int near *extra     = desc->extra_bits;
+    int base            = desc->extra_base;
+    int max_code        = desc->max_code;
+    int max_length      = desc->max_length;
+    ct_data near *stree = desc->static_tree;
+    int h;              /* heap index */
+    int n, m;           /* iterate over the tree elements */
+    int bits;           /* bit length */
+    int xbits;          /* extra bits */
+    ush f;              /* frequency */
+    int overflow = 0;   /* number of elements with bit length too large */
+
+    for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;
+
+    /* In a first pass, compute the optimal bit lengths (which may
+     * overflow in the case of the bit length tree).
+     */
+    tree[heap[heap_max]].Len = 0; /* root of the heap */
+
+    for (h = heap_max+1; h < HEAP_SIZE; h++) {
+        n = heap[h];
+        bits = tree[tree[n].Dad].Len + 1;
+        if (bits > max_length) bits = max_length, overflow++;
+        tree[n].Len = (ush)bits;
+        /* We overwrite tree[n].Dad which is no longer needed */
+
+        if (n > max_code) continue; /* not a leaf node */
+
+        bl_count[bits]++;
+        xbits = 0;
+        if (n >= base) xbits = extra[n-base];
+        f = tree[n].Freq;
+        opt_len += (ulg)f * (bits + xbits);
+        if (stree) static_len += (ulg)f * (stree[n].Len + xbits);
+    }
+    if (overflow == 0) return;
+
+    Trace((stderr,"\nbit length overflow\n"));
+    /* This happens for example on obj2 and pic of the Calgary corpus */
+
+    /* Find the first bit length which could increase: */
+    do {
+        bits = max_length-1;
+        while (bl_count[bits] == 0) bits--;
+        bl_count[bits]--;      /* move one leaf down the tree */
+        bl_count[bits+1] += 2; /* move one overflow item as its brother */
+        bl_count[max_length]--;
+        /* The brother of the overflow item also moves one step up,
+         * but this does not affect bl_count[max_length]
+         */
+        overflow -= 2;
+    } while (overflow > 0);
+
+    /* Now recompute all bit lengths, scanning in increasing frequency.
+     * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
+     * lengths instead of fixing only the wrong ones. This idea is taken
+     * from 'ar' written by Haruhiko Okumura.)
+     */
+    for (bits = max_length; bits != 0; bits--) {
+        n = bl_count[bits];
+        while (n != 0) {
+            m = heap[--h];
+            if (m > max_code) continue;
+            if (tree[m].Len != (unsigned) bits) {
+                Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits));
+                opt_len += ((long)bits-(long)tree[m].Len)*(long)tree[m].Freq;
+                tree[m].Len = (ush)bits;
+            }
+            n--;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Generate the codes for a given tree and bit counts (which need not be
+ * optimal).
+ * IN assertion: the array bl_count contains the bit length statistics for
+ * the given tree and the field len is set for all tree elements.
+ * OUT assertion: the field code is set for all tree elements of non
+ *     zero code length.
+ */
+local void gen_codes (tree, max_code)
+    ct_data near *tree;        /* the tree to decorate */
+    int max_code;              /* largest code with non zero frequency */
+{
+    ush next_code[MAX_BITS+1]; /* next code value for each bit length */
+    ush code = 0;              /* running code value */
+    int bits;                  /* bit index */
+    int n;                     /* code index */
+
+    /* The distribution counts are first used to generate the code values
+     * without bit reversal.
+     */
+    for (bits = 1; bits <= MAX_BITS; bits++) {
+        next_code[bits] = code = (code + bl_count[bits-1]) << 1;
+    }
+    /* Check that the bit counts in bl_count are consistent. The last code
+     * must be all ones.
+     */
+    Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
+            "inconsistent bit counts");
+    Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
+
+    for (n = 0;  n <= max_code; n++) {
+        int len = tree[n].Len;
+        if (len == 0) continue;
+        /* Now reverse the bits */
+        tree[n].Code = bi_reverse(next_code[len]++, len);
+
+        Tracec(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
+             n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1));
+    }
+}
+
+/* ===========================================================================
+ * Construct one Huffman tree and assigns the code bit strings and lengths.
+ * Update the total bit length for the current block.
+ * IN assertion: the field freq is set for all tree elements.
+ * OUT assertions: the fields len and code are set to the optimal bit length
+ *     and corresponding code. The length opt_len is updated; static_len is
+ *     also updated if stree is not null. The field max_code is set.
+ */
+local void build_tree(desc)
+    tree_desc near *desc; /* the tree descriptor */
+{
+    ct_data near *tree   = desc->dyn_tree;
+    ct_data near *stree  = desc->static_tree;
+    int elems            = desc->elems;
+    int n, m;          /* iterate over heap elements */
+    int max_code = -1; /* largest code with non zero frequency */
+    int node = elems;  /* next internal node of the tree */
+
+    /* Construct the initial heap, with least frequent element in
+     * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
+     * heap[0] is not used.
+     */
+    heap_len = 0, heap_max = HEAP_SIZE;
+
+    for (n = 0; n < elems; n++) {
+        if (tree[n].Freq != 0) {
+            heap[++heap_len] = max_code = n;
+            depth[n] = 0;
+        } else {
+            tree[n].Len = 0;
+        }
+    }
+
+    /* The pkzip format requires that at least one distance code exists,
+     * and that at least one bit should be sent even if there is only one
+     * possible code. So to avoid special checks later on we force at least
+     * two codes of non zero frequency.
+     */
+    while (heap_len < 2) {
+        int new = heap[++heap_len] = (max_code < 2 ? ++max_code : 0);
+        tree[new].Freq = 1;
+        depth[new] = 0;
+        opt_len--; if (stree) static_len -= stree[new].Len;
+        /* new is 0 or 1 so it does not have extra bits */
+    }
+    desc->max_code = max_code;
+
+    /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
+     * establish sub-heaps of increasing lengths:
+     */
+    for (n = heap_len/2; n >= 1; n--) pqdownheap(tree, n);
+
+    /* Construct the Huffman tree by repeatedly combining the least two
+     * frequent nodes.
+     */
+    do {
+        pqremove(tree, n);   /* n = node of least frequency */
+        m = heap[SMALLEST];  /* m = node of next least frequency */
+
+        heap[--heap_max] = n; /* keep the nodes sorted by frequency */
+        heap[--heap_max] = m;
+
+        /* Create a new node father of n and m */
+        tree[node].Freq = tree[n].Freq + tree[m].Freq;
+        depth[node] = (uch) (MAX(depth[n], depth[m]) + 1);
+        tree[n].Dad = tree[m].Dad = (ush)node;
+#ifdef DUMP_BL_TREE
+        if (tree == bl_tree) {
+            fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)",
+                    node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq);
+        }
+#endif
+        /* and insert the new node in the heap */
+        heap[SMALLEST] = node++;
+        pqdownheap(tree, SMALLEST);
+
+    } while (heap_len >= 2);
+
+    heap[--heap_max] = heap[SMALLEST];
+
+    /* At this point, the fields freq and dad are set. We can now
+     * generate the bit lengths.
+     */
+    gen_bitlen((tree_desc near *)desc);
+
+    /* The field len is now set, we can generate the bit codes */
+    gen_codes ((ct_data near *)tree, max_code);
+}
+
+/* ===========================================================================
+ * Scan a literal or distance tree to determine the frequencies of the codes
+ * in the bit length tree. Updates opt_len to take into account the repeat
+ * counts. (The contribution of the bit length codes will be added later
+ * during the construction of bl_tree.)
+ */
+local void scan_tree (tree, max_code)
+    ct_data near *tree; /* the tree to be scanned */
+    int max_code;       /* and its largest code of non zero frequency */
+{
+    int n;                     /* iterates over all tree elements */
+    int prevlen = -1;          /* last emitted length */
+    int curlen;                /* length of current code */
+    int nextlen = tree[0].Len; /* length of next code */
+    int count = 0;             /* repeat count of the current code */
+    int max_count = 7;         /* max repeat count */
+    int min_count = 4;         /* min repeat count */
+
+    if (nextlen == 0) max_count = 138, min_count = 3;
+    tree[max_code+1].Len = (ush)0xffff; /* guard */
+
+    for (n = 0; n <= max_code; n++) {
+        curlen = nextlen; nextlen = tree[n+1].Len;
+        if (++count < max_count && curlen == nextlen) {
+            continue;
+        } else if (count < min_count) {
+            bl_tree[curlen].Freq += count;
+        } else if (curlen != 0) {
+            if (curlen != prevlen) bl_tree[curlen].Freq++;
+            bl_tree[REP_3_6].Freq++;
+        } else if (count <= 10) {
+            bl_tree[REPZ_3_10].Freq++;
+        } else {
+            bl_tree[REPZ_11_138].Freq++;
+        }
+        count = 0; prevlen = curlen;
+        if (nextlen == 0) {
+            max_count = 138, min_count = 3;
+        } else if (curlen == nextlen) {
+            max_count = 6, min_count = 3;
+        } else {
+            max_count = 7, min_count = 4;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Send a literal or distance tree in compressed form, using the codes in
+ * bl_tree.
+ */
+local void send_tree (tree, max_code)
+    ct_data near *tree; /* the tree to be scanned */
+    int max_code;       /* and its largest code of non zero frequency */
+{
+    int n;                     /* iterates over all tree elements */
+    int prevlen = -1;          /* last emitted length */
+    int curlen;                /* length of current code */
+    int nextlen = tree[0].Len; /* length of next code */
+    int count = 0;             /* repeat count of the current code */
+    int max_count = 7;         /* max repeat count */
+    int min_count = 4;         /* min repeat count */
+
+    /* tree[max_code+1].Len = -1; */  /* guard already set */
+    if (nextlen == 0) max_count = 138, min_count = 3;
+
+    for (n = 0; n <= max_code; n++) {
+        curlen = nextlen; nextlen = tree[n+1].Len;
+        if (++count < max_count && curlen == nextlen) {
+            continue;
+        } else if (count < min_count) {
+            do { send_code(curlen, bl_tree); } while (--count != 0);
+
+        } else if (curlen != 0) {
+            if (curlen != prevlen) {
+                send_code(curlen, bl_tree); count--;
+            }
+            Assert(count >= 3 && count <= 6, " 3_6?");
+            send_code(REP_3_6, bl_tree); send_bits(count-3, 2);
+
+        } else if (count <= 10) {
+            send_code(REPZ_3_10, bl_tree); send_bits(count-3, 3);
+
+        } else {
+            send_code(REPZ_11_138, bl_tree); send_bits(count-11, 7);
+        }
+        count = 0; prevlen = curlen;
+        if (nextlen == 0) {
+            max_count = 138, min_count = 3;
+        } else if (curlen == nextlen) {
+            max_count = 6, min_count = 3;
+        } else {
+            max_count = 7, min_count = 4;
+        }
+    }
+}
+
+/* ===========================================================================
+ * Construct the Huffman tree for the bit lengths and return the index in
+ * bl_order of the last bit length code to send.
+ */
+local int build_bl_tree()
+{
+    int max_blindex;  /* index of last bit length code of non zero freq */
+
+    /* Determine the bit length frequencies for literal and distance trees */
+    scan_tree((ct_data near *)dyn_ltree, l_desc.max_code);
+    scan_tree((ct_data near *)dyn_dtree, d_desc.max_code);
+
+    /* Build the bit length tree: */
+    build_tree((tree_desc near *)(&bl_desc));
+    /* opt_len now includes the length of the tree representations, except
+     * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
+     */
+
+    /* Determine the number of bit length codes to send. The pkzip format
+     * requires that at least 4 bit length codes be sent. (appnote.txt says
+     * 3 but the actual value used is 4.)
+     */
+    for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
+        if (bl_tree[bl_order[max_blindex]].Len != 0) break;
+    }
+    /* Update opt_len to include the bit length tree and counts */
+    opt_len += 3*(max_blindex+1) + 5+5+4;
+    Tracev((stderr, "\ndyn trees: dyn %lu, stat %lu", opt_len, static_len));
+
+    return max_blindex;
+}
+
+/* ===========================================================================
+ * Send the header for a block using dynamic Huffman trees: the counts, the
+ * lengths of the bit length codes, the literal tree and the distance tree.
+ * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
+ */
+local void send_all_trees(lcodes, dcodes, blcodes)
+    int lcodes, dcodes, blcodes; /* number of codes for each tree */
+{
+    int rank;                    /* index in bl_order */
+
+    Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
+    Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
+            "too many codes");
+    Tracev((stderr, "\nbl counts: "));
+    send_bits(lcodes-257, 5); /* not +255 as stated in appnote.txt */
+    send_bits(dcodes-1,   5);
+    send_bits(blcodes-4,  4); /* not -3 as stated in appnote.txt */
+    for (rank = 0; rank < blcodes; rank++) {
+        Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
+        send_bits(bl_tree[bl_order[rank]].Len, 3);
+    }
+
+    send_tree((ct_data near *)dyn_ltree, lcodes-1); /* send the literal tree */
+
+    send_tree((ct_data near *)dyn_dtree, dcodes-1); /* send the distance tree */
+}
+
+/* ===========================================================================
+ * Determine the best encoding for the current block: dynamic trees, static
+ * trees or store, and output the encoded block to the zip file. This function
+ * returns the total compressed length for the file so far.
+ */
+off_t flush_block(buf, stored_len, eof)
+    char *buf;        /* input block, or NULL if too old */
+    ulg stored_len;   /* length of input block */
+    int eof;          /* true if this is the last block for a file */
+{
+    ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
+    int max_blindex;  /* index of last bit length code of non zero freq */
+
+    flag_buf[last_flags] = flags; /* Save the flags for the last 8 items */
+
+     /* Check if the file is ascii or binary */
+    if (*file_type == (ush)UNKNOWN) set_file_type();
+
+    /* Construct the literal and distance trees */
+    build_tree((tree_desc near *)(&l_desc));
+    Tracev((stderr, "\nlit data: dyn %lu, stat %lu", opt_len, static_len));
+
+    build_tree((tree_desc near *)(&d_desc));
+    Tracev((stderr, "\ndist data: dyn %lu, stat %lu", opt_len, static_len));
+    /* At this point, opt_len and static_len are the total bit lengths of
+     * the compressed block data, excluding the tree representations.
+     */
+
+    /* Build the bit length tree for the above two trees, and get the index
+     * in bl_order of the last bit length code to send.
+     */
+    max_blindex = build_bl_tree();
+
+    /* Determine the best encoding. Compute first the block length in bytes */
+    opt_lenb = (opt_len+3+7)>>3;
+    static_lenb = (static_len+3+7)>>3;
+    input_len += stored_len; /* for debugging only */
+
+    Trace((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u dist %u ",
+            opt_lenb, opt_len, static_lenb, static_len, stored_len,
+            last_lit, last_dist));
+
+    if (static_lenb <= opt_lenb) opt_lenb = static_lenb;
+
+    /* If compression failed and this is the first and last block,
+     * and if the zip file can be seeked (to rewrite the local header),
+     * the whole file is transformed into a stored file:
+     */
+#ifdef FORCE_METHOD
+    if (level == 1 && eof && compressed_len == 0L) { /* force stored file */
+#else
+    if (stored_len <= opt_lenb && eof && compressed_len == 0L && seekable()) {
+#endif
+        /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */
+        if (buf == (char*)0) error ("block vanished");
+
+        copy_block(buf, (unsigned)stored_len, 0); /* without header */
+        compressed_len = stored_len << 3;
+        *file_method = STORED;
+
+#ifdef FORCE_METHOD
+    } else if (level == 2 && buf != (char*)0) { /* force stored block */
+#else
+    } else if (stored_len+4 <= opt_lenb && buf != (char*)0) {
+                       /* 4: two words for the lengths */
+#endif
+        /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
+         * Otherwise we can't have processed more than WSIZE input bytes since
+         * the last block flush, because compression would have been
+         * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
+         * transform a block into a stored block.
+         */
+        send_bits((STORED_BLOCK<<1)+eof, 3);  /* send block type */
+        compressed_len = (compressed_len + 3 + 7) & ~7L;
+        compressed_len += (stored_len + 4) << 3;
+
+        copy_block(buf, (unsigned)stored_len, 1); /* with header */
+
+#ifdef FORCE_METHOD
+    } else if (level == 3) { /* force static trees */
+#else
+    } else if (static_lenb == opt_lenb) {
+#endif
+        send_bits((STATIC_TREES<<1)+eof, 3);
+        compress_block((ct_data near *)static_ltree, (ct_data near *)static_dtree);
+        compressed_len += 3 + static_len;
+    } else {
+        send_bits((DYN_TREES<<1)+eof, 3);
+        send_all_trees(l_desc.max_code+1, d_desc.max_code+1, max_blindex+1);
+        compress_block((ct_data near *)dyn_ltree, (ct_data near *)dyn_dtree);
+        compressed_len += 3 + opt_len;
+    }
+    Assert (compressed_len == bits_sent, "bad compressed size");
+    init_block();
+
+    if (eof) {
+        Assert (input_len == bytes_in, "bad input size");
+        bi_windup();
+        compressed_len += 7;  /* align on byte boundary */
+    }
+
+    return compressed_len >> 3;
+}
+
+/* ===========================================================================
+ * Save the match info and tally the frequency counts. Return true if
+ * the current block must be flushed.
+ */
+int ct_tally (dist, lc)
+    int dist;  /* distance of matched string */
+    int lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */
+{
+    l_buf[last_lit++] = (uch)lc;
+    if (dist == 0) {
+        /* lc is the unmatched char */
+        dyn_ltree[lc].Freq++;
+    } else {
+        /* Here, lc is the match length - MIN_MATCH */
+        dist--;             /* dist = match distance - 1 */
+        Assert((ush)dist < (ush)MAX_DIST &&
+               (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
+               (ush)d_code(dist) < (ush)D_CODES,  "ct_tally: bad match");
+
+        dyn_ltree[length_code[lc]+LITERALS+1].Freq++;
+        dyn_dtree[d_code(dist)].Freq++;
+
+        d_buf[last_dist++] = (ush)dist;
+        flags |= flag_bit;
+    }
+    flag_bit <<= 1;
+
+    /* Output the flags if they fill a byte: */
+    if ((last_lit & 7) == 0) {
+        flag_buf[last_flags++] = flags;
+        flags = 0, flag_bit = 1;
+    }
+    /* Try to guess if it is profitable to stop the current block here */
+    if (level > 2 && (last_lit & 0xfff) == 0) {
+        /* Compute an upper bound for the compressed length */
+        ulg out_length = (ulg)last_lit*8L;
+        ulg in_length = (ulg)strstart-block_start;
+        int dcode;
+        for (dcode = 0; dcode < D_CODES; dcode++) {
+            out_length += (ulg)dyn_dtree[dcode].Freq*(5L+extra_dbits[dcode]);
+        }
+        out_length >>= 3;
+        Trace((stderr,"\nlast_lit %u, last_dist %u, in %ld, out ~%ld(%ld%%) ",
+               last_lit, last_dist, in_length, out_length,
+               100L - out_length*100L/in_length));
+        if (last_dist < last_lit/2 && out_length < in_length/2) return 1;
+    }
+    return (last_lit == LIT_BUFSIZE-1 || last_dist == DIST_BUFSIZE);
+    /* We avoid equality with LIT_BUFSIZE because of wraparound at 64K
+     * on 16 bit machines and because stored blocks are restricted to
+     * 64K-1 bytes.
+     */
+}
+
+/* ===========================================================================
+ * Send the block data compressed using the given Huffman trees
+ */
+local void compress_block(ltree, dtree)
+    ct_data near *ltree; /* literal tree */
+    ct_data near *dtree; /* distance tree */
+{
+    unsigned dist;      /* distance of matched string */
+    int lc;             /* match length or unmatched char (if dist == 0) */
+    unsigned lx = 0;    /* running index in l_buf */
+    unsigned dx = 0;    /* running index in d_buf */
+    unsigned fx = 0;    /* running index in flag_buf */
+    uch flag = 0;       /* current flags */
+    unsigned code;      /* the code to send */
+    int extra;          /* number of extra bits to send */
+
+    if (last_lit != 0) do {
+        if ((lx & 7) == 0) flag = flag_buf[fx++];
+        lc = l_buf[lx++];
+        if ((flag & 1) == 0) {
+            send_code(lc, ltree); /* send a literal byte */
+            Tracecv(isgraph(lc), (stderr," '%c' ", lc));
+        } else {
+            /* Here, lc is the match length - MIN_MATCH */
+            code = length_code[lc];
+            send_code(code+LITERALS+1, ltree); /* send the length code */
+            extra = extra_lbits[code];
+            if (extra != 0) {
+                lc -= base_length[code];
+                send_bits(lc, extra);        /* send the extra length bits */
+            }
+            dist = d_buf[dx++];
+            /* Here, dist is the match distance - 1 */
+            code = d_code(dist);
+            Assert (code < D_CODES, "bad d_code");
+
+            send_code(code, dtree);       /* send the distance code */
+            extra = extra_dbits[code];
+            if (extra != 0) {
+                dist -= base_dist[code];
+                send_bits(dist, extra);   /* send the extra distance bits */
+            }
+        } /* literal or match pair ? */
+        flag >>= 1;
+    } while (lx < last_lit);
+
+    send_code(END_BLOCK, ltree);
+}
+
+/* ===========================================================================
+ * Set the file type to ASCII or BINARY, using a crude approximation:
+ * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
+ * IN assertion: the fields freq of dyn_ltree are set and the total of all
+ * frequencies does not exceed 64K (to fit in an int on 16 bit machines).
+ */
+local void set_file_type()
+{
+    int n = 0;
+    unsigned ascii_freq = 0;
+    unsigned bin_freq = 0;
+    while (n < 7)        bin_freq += dyn_ltree[n++].Freq;
+    while (n < 128)    ascii_freq += dyn_ltree[n++].Freq;
+    while (n < LITERALS) bin_freq += dyn_ltree[n++].Freq;
+    *file_type = bin_freq > (ascii_freq >> 2) ? BINARY : ASCII;
+    if (*file_type == BINARY && translate_eol) {
+        warning ("-l used on binary file");
+    }
+}
diff --git a/isys/gzlib/unzip.c b/isys/gzlib/unzip.c
new file mode 100644
index 000000000..a672b62d0
--- /dev/null
+++ b/isys/gzlib/unzip.c
@@ -0,0 +1,204 @@
+/* unzip.c -- decompress files in gzip or pkzip format.
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ *
+ * The code in this file is derived from the file funzip.c written
+ * and put in the public domain by Mark Adler.
+ */
+
+/*
+   This version can extract files in gzip or pkzip format.
+   For the latter, only the first entry is extracted, and it has to be
+   either deflated or stored.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+#include <config.h>
+#include "tailor.h"
+#include "gzip.h"
+#include "crypt.h"
+
+/* PKZIP header definitions */
+#define LOCSIG 0x04034b50L      /* four-byte lead-in (lsb first) */
+#define LOCFLG 6                /* offset of bit flag */
+#define  CRPFLG 1               /*  bit for encrypted entry */
+#define  EXTFLG 8               /*  bit for extended local header */
+#define LOCHOW 8                /* offset of compression method */
+#define LOCTIM 10               /* file mod time (for decryption) */
+#define LOCCRC 14               /* offset of crc */
+#define LOCSIZ 18               /* offset of compressed size */
+#define LOCLEN 22               /* offset of uncompressed length */
+#define LOCFIL 26               /* offset of file name field length */
+#define LOCEXT 28               /* offset of extra field length */
+#define LOCHDR 30               /* size of local header, including sig */
+#define EXTHDR 16               /* size of extended local header, inc sig */
+#define RAND_HEAD_LEN  12       /* length of encryption random header */
+
+
+/* Globals */
+
+int decrypt;        /* flag to turn on decryption */
+char *key;          /* not used--needed to link crypt.c */
+int pkzip = 0;      /* set for a pkzip file */
+int ext_header = 0; /* set if extended local header */
+
+/* ===========================================================================
+ * Check zip file and advance inptr to the start of the compressed data.
+ * Get ofname from the local header if necessary.
+ */
+int check_zipfile(in)
+    int in;   /* input file descriptors */
+{
+    uch *h = inbuf + inptr; /* first local header */
+
+    ifd = in;
+
+    /* Check validity of local header, and skip name and extra fields */
+    inptr += LOCHDR + SH(h + LOCFIL) + SH(h + LOCEXT);
+
+    if (inptr > insize || LG(h) != LOCSIG) {
+	fprintf(stderr, "\n%s: %s: not a valid zip file\n",
+		progname, ifname);
+	exit_code = ERROR;
+	return ERROR;
+    }
+    method = h[LOCHOW];
+    if (method != STORED && method != DEFLATED) {
+	fprintf(stderr,
+		"\n%s: %s: first entry not deflated or stored -- use unzip\n",
+		progname, ifname);
+	exit_code = ERROR;
+	return ERROR;
+    }
+
+    /* If entry encrypted, decrypt and validate encryption header */
+    if ((decrypt = h[LOCFLG] & CRPFLG) != 0) {
+	fprintf(stderr, "\n%s: %s: encrypted file -- use unzip\n",
+		progname, ifname);
+	exit_code = ERROR;
+	return ERROR;
+    }
+
+    /* Save flags for unzip() */
+    ext_header = (h[LOCFLG] & EXTFLG) != 0;
+    pkzip = 1;
+
+    /* Get ofname and time stamp from local header (to be done) */
+    return OK;
+}
+
+/* ===========================================================================
+ * Unzip in to out.  This routine works on both gzip and pkzip files.
+ *
+ * IN assertions: the buffer inbuf contains already the beginning of
+ *   the compressed data, from offsets inptr to insize-1 included.
+ *   The magic header has already been checked. The output buffer is cleared.
+ */
+int unzip(in, out)
+    int in, out;   /* input and output file descriptors */
+{
+    ulg orig_crc = 0;       /* original crc */
+    ulg orig_len = 0;       /* original uncompressed length */
+    int n;
+    uch buf[EXTHDR];        /* extended local header */
+    int err = OK;
+
+    ifd = in;
+    ofd = out;
+
+    updcrc(NULL, 0);           /* initialize crc */
+
+    if (pkzip && !ext_header) {  /* crc and length at the end otherwise */
+	orig_crc = LG(inbuf + LOCCRC);
+	orig_len = LG(inbuf + LOCLEN);
+    }
+
+    /* Decompress */
+    if (method == DEFLATED)  {
+
+	int res = inflate();
+
+	if (res == 3) {
+	    gzerror("out of memory");
+	} else if (res != 0) {
+	    gzerror("invalid compressed data--format violated");
+	}
+
+    } else if (pkzip && method == STORED) {
+
+	register ulg n = LG(inbuf + LOCLEN);
+
+	if (n != LG(inbuf + LOCSIZ) - (decrypt ? RAND_HEAD_LEN : 0)) {
+
+	    fprintf(stderr, "len %ld, siz %ld\n", n, LG(inbuf + LOCSIZ));
+	    gzerror("invalid compressed data--length mismatch");
+	}
+	while (n--) {
+	    uch c = (uch)get_byte();
+	    put_ubyte(c);
+	}
+	flush_window();
+    } else {
+	gzerror("internal error, invalid method");
+    }
+
+    /* Get the crc and original length */
+    if (!pkzip) {
+        /* crc32  (see algorithm.doc)
+	 * uncompressed input size modulo 2^32
+         */
+	for (n = 0; n < 8; n++) {
+	    buf[n] = (uch)get_byte(); /* may cause an error if EOF */
+	}
+	orig_crc = LG(buf);
+	orig_len = LG(buf+4);
+
+    } else if (ext_header) {  /* If extended header, check it */
+	/* signature - 4bytes: 0x50 0x4b 0x07 0x08
+	 * CRC-32 value
+         * compressed size 4-bytes
+         * uncompressed size 4-bytes
+	 */
+	for (n = 0; n < EXTHDR; n++) {
+	    buf[n] = (uch)get_byte(); /* may cause an error if EOF */
+	}
+	orig_crc = LG(buf+4);
+	orig_len = LG(buf+12);
+    }
+
+    /* Validate decompression */
+    if (orig_crc != updcrc(outbuf, 0)) {
+	fprintf(stderr, "\n%s: %s: invalid compressed data--crc error\n",
+		progname, ifname);
+	err = ERROR;
+    }
+    if (orig_len != (ulg)(bytes_out & 0xffffffff)) {
+	fprintf(stderr, "\n%s: %s: invalid compressed data--length error\n",
+		progname, ifname);
+	err = ERROR;
+    }
+
+    /* Check if there are more entries in a pkzip file */
+    if (pkzip && inptr + 4 < insize && LG(inbuf+inptr) == LOCSIG) {
+	if (to_stdout) {
+	    WARN((stderr,
+		  "%s: %s has more than one entry--rest ignored\n",
+		  progname, ifname));
+	} else {
+	    /* Don't destroy the input zip file */
+	    fprintf(stderr,
+		    "%s: %s has more than one entry -- unchanged\n",
+		    progname, ifname);
+	    err = ERROR;
+	}
+    }
+    ext_header = pkzip = 0; /* for next file */
+    if (err == OK) return OK;
+    exit_code = ERROR;
+    if (!test) abort_gzip();
+    return err;
+}
diff --git a/isys/gzlib/util.c b/isys/gzlib/util.c
new file mode 100644
index 000000000..93e8b823a
--- /dev/null
+++ b/isys/gzlib/util.c
@@ -0,0 +1,538 @@
+/* util.c -- utility functions for gzip support
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+#include <config.h>
+#include <ctype.h>
+#include <errno.h>
+
+#include "tailor.h"
+
+#ifdef HAVE_LIMITS_H
+#  include <limits.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#  include <fcntl.h>
+#endif
+
+#if defined STDC_HEADERS || defined HAVE_STDLIB_H
+#  include <stdlib.h>
+#else
+   extern int errno;
+#endif
+
+#include "gzip.h"
+#include "crypt.h"
+
+#ifndef CHAR_BIT
+#  define CHAR_BIT 8
+#endif
+
+extern ulg crc_32_tab[];   /* crc table, defined below */
+
+/* ===========================================================================
+ * Copy input to output unchanged: zcat == cat with --force.
+ * IN assertion: insize bytes have already been read in inbuf.
+ */
+int copy(in, out)
+    int in, out;   /* input and output file descriptors */
+{
+    errno = 0;
+    while (insize != 0 && (int)insize != -1) {
+	write_buf(out, (char*)inbuf, insize);
+	bytes_out += insize;
+	insize = read(in, (char*)inbuf, INBUFSIZ);
+    }
+    if ((int)insize == -1) {
+	read_error();
+    }
+    bytes_in = bytes_out;
+    return OK;
+}
+
+/* ===========================================================================
+ * Run a set of bytes through the crc shift register.  If s is a NULL
+ * pointer, then initialize the crc shift register contents instead.
+ * Return the current crc in either case.
+ */
+ulg updcrc(s, n)
+    uch *s;                 /* pointer to bytes to pump through */
+    unsigned n;             /* number of bytes in s[] */
+{
+    register ulg c;         /* temporary variable */
+
+    static ulg crc = (ulg)0xffffffffL; /* shift register contents */
+
+    if (s == NULL) {
+	c = 0xffffffffL;
+    } else {
+	c = crc;
+        if (n) do {
+            c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8);
+        } while (--n);
+    }
+    crc = c;
+    return c ^ 0xffffffffL;       /* (instead of ~c for 64-bit machines) */
+}
+
+/* ===========================================================================
+ * Clear input and output buffers
+ */
+void clear_bufs()
+{
+    outcnt = 0;
+    insize = inptr = 0;
+    bytes_in = bytes_out = 0L;
+}
+
+/* ===========================================================================
+ * Fill the input buffer. This is called only when the buffer is empty.
+ */
+int fill_inbuf(eof_ok)
+    int eof_ok;          /* set if EOF acceptable as a result */
+{
+    int len;
+
+    /* Read as much as possible */
+    insize = 0;
+    do {
+	len = read(ifd, (char*)inbuf+insize, INBUFSIZ-insize);
+	if (len == 0) break;
+	if (len == -1) {
+	  read_error();
+	  break;
+	}
+	insize += len;
+    } while (insize < INBUFSIZ);
+
+    if (insize == 0) {
+	if (eof_ok) return EOF;
+	flush_window();
+	errno = 0;
+	read_error();
+    }
+    bytes_in += (off_t)insize;
+    inptr = 1;
+    return inbuf[0];
+}
+
+/* ===========================================================================
+ * Write the output buffer outbuf[0..outcnt-1] and update bytes_out.
+ * (used for the compressed data only)
+ */
+void flush_outbuf()
+{
+    if (outcnt == 0) return;
+
+    write_buf(ofd, (char *)outbuf, outcnt);
+    bytes_out += (off_t)outcnt;
+    outcnt = 0;
+}
+
+/* ===========================================================================
+ * Write the output window window[0..outcnt-1] and update crc and bytes_out.
+ * (Used for the decompressed data only.)
+ */
+void flush_window()
+{
+    if (outcnt == 0) return;
+    updcrc(window, outcnt);
+
+    if (!test) {
+	write_buf(ofd, (char *)window, outcnt);
+    }
+    bytes_out += (off_t)outcnt;
+    outcnt = 0;
+}
+
+/* ===========================================================================
+ * Does the same as write(), but also handles partial pipe writes and checks
+ * for error return.
+ */
+void write_buf(fd, buf, cnt)
+    int       fd;
+    voidp     buf;
+    unsigned  cnt;
+{
+    unsigned  n;
+
+    while ((n = write(fd, buf, cnt)) != cnt) {
+	if (n == (unsigned)(-1)) {
+	    write_error();
+	}
+	cnt -= n;
+	buf = (voidp)((char*)buf+n);
+    }
+}
+
+/* ========================================================================
+ * Put string s in lower case, return s.
+ */
+char *strlwr(s)
+    char *s;
+{
+    char *t;
+    for (t = s; *t; t++)
+      *t = tolow ((unsigned char) *t);
+    return s;
+}
+
+/* ========================================================================
+ * Return the base name of a file (remove any directory prefix and
+ * any version suffix). For systems with file names that are not
+ * case sensitive, force the base name to lower case.
+ */
+char *base_name(fname)
+    char *fname;
+{
+    char *p;
+
+    if ((p = strrchr(fname, PATH_SEP))  != NULL) fname = p+1;
+#ifdef PATH_SEP2
+    if ((p = strrchr(fname, PATH_SEP2)) != NULL) fname = p+1;
+#endif
+#ifdef PATH_SEP3
+    if ((p = strrchr(fname, PATH_SEP3)) != NULL) fname = p+1;
+#endif
+#ifdef SUFFIX_SEP
+    if ((p = strrchr(fname, SUFFIX_SEP)) != NULL) *p = '\0';
+#endif
+    if (casemap('A') == 'a') strlwr(fname);
+    return fname;
+}
+
+/* ========================================================================
+ * Unlink a file, working around the unlink readonly bug (if present).
+ */
+int xunlink (filename)
+     char *filename;
+{
+  int r = unlink (filename);
+
+#ifdef UNLINK_READONLY_BUG
+  if (r != 0)
+    {
+      int e = errno;
+      if (chmod (filename, S_IWUSR) != 0)
+	{
+	  errno = e;
+	  return -1;
+	}
+
+      r = unlink (filename);
+    }
+#endif
+
+  return r;
+}
+
+/* ========================================================================
+ * Make a file name legal for file systems not allowing file names with
+ * multiple dots or starting with a dot (such as MSDOS), by changing
+ * all dots except the last one into underlines.  A target dependent
+ * function can be used instead of this simple function by defining the macro
+ * MAKE_LEGAL_NAME in tailor.h and providing the function in a target
+ * dependent module.
+ */
+void make_simple_name(name)
+    char *name;
+{
+    char *p = strrchr(name, '.');
+    if (p == NULL) return;
+    if (p == name) p++;
+    do {
+        if (*--p == '.') *p = '_';
+    } while (p != name);
+}
+
+
+#if !defined HAVE_STRING_H && !defined STDC_HEADERS
+
+/* Provide missing strspn and strcspn functions. */
+
+#  ifndef __STDC__
+#    define const
+#  endif
+
+int strspn  OF((const char *s, const char *accept));
+int strcspn OF((const char *s, const char *reject));
+
+/* ========================================================================
+ * Return the length of the maximum initial segment
+ * of s which contains only characters in accept.
+ */
+int strspn(s, accept)
+    const char *s;
+    const char *accept;
+{
+    register const char *p;
+    register const char *a;
+    register int count = 0;
+
+    for (p = s; *p != '\0'; ++p) {
+	for (a = accept; *a != '\0'; ++a) {
+	    if (*p == *a) break;
+	}
+	if (*a == '\0') return count;
+	++count;
+    }
+    return count;
+}
+
+/* ========================================================================
+ * Return the length of the maximum inital segment of s
+ * which contains no characters from reject.
+ */
+int strcspn(s, reject)
+    const char *s;
+    const char *reject;
+{
+    register int count = 0;
+
+    while (*s != '\0') {
+	if (strchr(reject, *s++) != NULL) return count;
+	++count;
+    }
+    return count;
+}
+
+#endif
+
+/* ========================================================================
+ * Add an environment variable (if any) before argv, and update argc.
+ * Return the expanded environment variable to be freed later, or NULL 
+ * if no options were added to argv.
+ */
+#define SEPARATOR	" \t"	/* separators in env variable */
+
+char *add_envopt(argcp, argvp, env)
+    int *argcp;          /* pointer to argc */
+    char ***argvp;       /* pointer to argv */
+    char *env;           /* name of environment variable */
+{
+    char *p;             /* running pointer through env variable */
+    char **oargv;        /* runs through old argv array */
+    char **nargv;        /* runs through new argv array */
+    int	 oargc = *argcp; /* old argc */
+    int  nargc = 0;      /* number of arguments in env variable */
+
+    env = (char*)getenv(env);
+    if (env == NULL) return NULL;
+
+    p = (char*)gzxmalloc(strlen(env)+1);
+    env = strcpy(p, env);                    /* keep env variable intact */
+
+    for (p = env; *p; nargc++ ) {            /* move through env */
+	p += strspn(p, SEPARATOR);	     /* skip leading separators */
+	if (*p == '\0') break;
+
+	p += strcspn(p, SEPARATOR);	     /* find end of word */
+	if (*p) *p++ = '\0';		     /* mark it */
+    }
+    if (nargc == 0) {
+	free(env);
+	return NULL;
+    }
+    *argcp += nargc;
+    /* Allocate the new argv array, with an extra element just in case
+     * the original arg list did not end with a NULL.
+     */
+    nargv = (char**)calloc(*argcp+1, sizeof(char *));
+    if (nargv == NULL) gzerror("out of memory");
+    oargv  = *argvp;
+    *argvp = nargv;
+
+    /* Copy the program name first */
+    if (oargc-- < 0) gzerror("argc<=0");
+    *(nargv++) = *(oargv++);
+
+    /* Then copy the environment args */
+    for (p = env; nargc > 0; nargc--) {
+	p += strspn(p, SEPARATOR);	     /* skip separators */
+	*(nargv++) = p;			     /* store start */
+	while (*p++) ;			     /* skip over word */
+    }
+
+    /* Finally copy the old args and add a NULL (usual convention) */
+    while (oargc--) *(nargv++) = *(oargv++);
+    *nargv = NULL;
+    return env;
+}
+
+/* ========================================================================
+ * Error handlers.
+ */
+void gzerror(m)
+    char *m;
+{
+    fprintf(stderr, "\n%s: %s: %s\n", progname, ifname, m);
+    abort_gzip();
+}
+
+void warning (m)
+    char *m;
+{
+    WARN ((stderr, "%s: %s: warning: %s\n", progname, ifname, m));
+}
+
+void read_error()
+{
+    int e = errno;
+    fprintf(stderr, "\n%s: ", progname);
+    if (e != 0) {
+	errno = e;
+	perror(ifname);
+    } else {
+	fprintf(stderr, "%s: unexpected end of file\n", ifname);
+    }
+    abort_gzip();
+}
+
+void write_error()
+{
+    int e = errno;
+    fprintf(stderr, "\n%s: ", progname);
+    errno = e;
+    perror(ofname);
+    abort_gzip();
+}
+
+/* ========================================================================
+ * Display compression ratio on the given stream on 6 characters.
+ */
+void display_ratio(num, den, file)
+    off_t num;
+    off_t den;
+    FILE *file;
+{
+    long ratio;  /* 1000 times the compression ratio */
+
+    if (den == 0) {
+	ratio = 0; /* no compression */
+    } else if (den < 2147483L) { /* (2**31 -1)/1000 */
+	ratio = 1000L*num/den;
+    } else {
+	ratio = num/(den/1000L);
+    }
+    if (ratio < 0) {
+	putc('-', file);
+	ratio = -ratio;
+    } else {
+	putc(' ', file);
+    }
+    fprint_off(file, ratio / 10, 2);
+    fprintf(file, ".%d%%", (int) (ratio % 10));
+}
+
+/* ========================================================================
+ * Print an off_t.  There's no completely portable way to use printf,
+ * so we do it ourselves.
+ */
+void fprint_off(file, offset, width)
+    FILE *file;
+    off_t offset;
+    int width;
+{
+    char buf[CHAR_BIT * sizeof (off_t)];
+    char *p = buf + sizeof buf;
+    int negative = offset < 0;
+    /* Don't negate offset here; it might overflow.  */
+    do {
+	int remainder = offset % 10;
+	int quotient = offset / 10;
+	if (offset < 0 && 0 < remainder) {
+	    remainder -= 10;
+	    quotient++;
+	}
+	*--p = (remainder < 0 ? -remainder : remainder) + '0';
+	width--;
+	offset = quotient;
+    } while (offset != 0);
+    for (width -= negative;  0 < width;  width--) {
+	putc (' ', file);
+    }
+    if (negative) {
+	putc ('-', file);
+    }
+    for (;  p < buf + sizeof buf;  p++)
+	putc (*p, file);
+}
+
+/* ========================================================================
+ * Semi-safe malloc -- never returns NULL.
+ */
+voidp gzxmalloc (size)
+    unsigned size;
+{
+    voidp cp = (voidp)malloc (size);
+
+    if (cp == NULL) gzerror("out of memory");
+    return cp;
+}
+
+/* ========================================================================
+ * Table of CRC-32's of all single-byte values (made by makecrc.c)
+ */
+ulg crc_32_tab[] = {
+  0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
+  0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
+  0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
+  0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
+  0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
+  0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
+  0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
+  0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
+  0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
+  0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
+  0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
+  0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
+  0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
+  0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
+  0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
+  0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
+  0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
+  0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
+  0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
+  0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
+  0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
+  0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
+  0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
+  0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
+  0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
+  0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
+  0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
+  0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
+  0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
+  0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
+  0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
+  0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
+  0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
+  0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
+  0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
+  0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
+  0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
+  0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
+  0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
+  0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
+  0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
+  0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
+  0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
+  0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
+  0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
+  0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
+  0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
+  0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
+  0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
+  0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
+  0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
+  0x2d02ef8dL
+};
diff --git a/isys/gzlib/zip.c b/isys/gzlib/zip.c
new file mode 100644
index 000000000..3c1b49773
--- /dev/null
+++ b/isys/gzlib/zip.c
@@ -0,0 +1,52 @@
+/* zip.c -- compress files to the gzip or pkzip format
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id$";
+#endif
+
+#include <config.h>
+#include <ctype.h>
+
+#include "tailor.h"
+#include "gzip.h"
+#include "crypt.h"
+
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#  include <fcntl.h>
+#endif
+
+local ulg crc;       /* crc on uncompressed file data */
+off_t header_bytes;   /* number of bytes in gzip header */
+
+
+/* ===========================================================================
+ * Read a new buffer from the current input file, perform end-of-line
+ * translation, and update the crc and input file size.
+ * IN assertion: size >= 2 (for end-of-line translation)
+ */
+int file_read(buf, size)
+    char *buf;
+    unsigned size;
+{
+    unsigned len;
+
+    Assert(insize == 0, "inbuf not empty");
+
+    len = read(ifd, buf, size);
+    if (len == 0) return (int)len;
+    if (len == (unsigned)-1) {
+	read_error();
+	return EOF;
+    }
+
+    crc = updcrc((uch*)buf, len);
+    bytes_in += (off_t)len;
+    return (int)len;
+}