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diff --git a/Build/source/utils/gzip/unpack.c b/Build/source/utils/gzip/unpack.c
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+/* unpack.c -- decompress files in pack 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: unpack.c,v 1.4 1993/06/11 19:25:36 jloup Exp $";
+#endif
+
+#include "tailor.h"
+#include "gzip.h"
+#include "crypt.h"
+
+#define MIN(a,b) ((a) <= (b) ? (a) : (b))
+/* The arguments must not have side effects. */
+
+#define MAX_BITLEN 25
+/* Maximum length of Huffman codes. (Minor modifications to the code
+ * would be needed to support 32 bits codes, but pack never generates
+ * more than 24 bits anyway.)
+ */
+
+#define LITERALS 256
+/* Number of literals, excluding the End of Block (EOB) code */
+
+#define MAX_PEEK 12
+/* Maximum number of 'peek' bits used to optimize traversal of the
+ * Huffman tree.
+ */
+
+local ulg orig_len; /* original uncompressed length */
+local int max_len; /* maximum bit length of Huffman codes */
+
+local uch literal[LITERALS];
+/* The literal bytes present in the Huffman tree. The EOB code is not
+ * represented.
+ */
+
+local int lit_base[MAX_BITLEN+1];
+/* All literals of a given bit length are contiguous in literal[] and
+ * have contiguous codes. literal[code+lit_base[len]] is the literal
+ * for a code of len bits.
+ */
+
+local int leaves [MAX_BITLEN+1]; /* Number of leaves for each bit length */
+local int parents[MAX_BITLEN+1]; /* Number of parents for each bit length */
+
+local int peek_bits; /* Number of peek bits currently used */
+
+/* local uch prefix_len[1 << MAX_PEEK]; */
+#define prefix_len outbuf
+/* For each bit pattern b of peek_bits bits, prefix_len[b] is the length
+ * of the Huffman code starting with a prefix of b (upper bits), or 0
+ * if all codes of prefix b have more than peek_bits bits. It is not
+ * necessary to have a huge table (large MAX_PEEK) because most of the
+ * codes encountered in the input stream are short codes (by construction).
+ * So for most codes a single lookup will be necessary.
+ */
+#if (1<<MAX_PEEK) > OUTBUFSIZ
+ error cannot overlay prefix_len and outbuf
+#endif
+
+local ulg bitbuf;
+/* Bits are added on the low part of bitbuf and read from the high part. */
+
+local int valid; /* number of valid bits in bitbuf */
+/* all bits above the last valid bit are always zero */
+
+/* Set code to the next 'bits' input bits without skipping them. code
+ * must be the name of a simple variable and bits must not have side effects.
+ * IN assertions: bits <= 25 (so that we still have room for an extra byte
+ * when valid is only 24), and mask = (1<<bits)-1.
+ */
+#define look_bits(code,bits,mask) \
+{ \
+ while (valid < (bits)) bitbuf = (bitbuf<<8) | (ulg)get_byte(), valid += 8; \
+ code = (bitbuf >> (valid-(bits))) & (mask); \
+}
+
+/* Skip the given number of bits (after having peeked at them): */
+#define skip_bits(bits) (valid -= (bits))
+
+#define clear_bitbuf() (valid = 0, bitbuf = 0)
+
+/* Local functions */
+
+local void read_tree OF((void));
+local void build_tree OF((void));
+
+/* ===========================================================================
+ * Read the Huffman tree.
+ */
+local void read_tree()
+{
+ int len; /* bit length */
+ int base; /* base offset for a sequence of leaves */
+ int n;
+
+ /* Read the original input size, MSB first */
+ orig_len = 0;
+ for (n = 1; n <= 4; n++) orig_len = (orig_len << 8) | (ulg)get_byte();
+
+ max_len = (int)get_byte(); /* maximum bit length of Huffman codes */
+ if (max_len > MAX_BITLEN) {
+ error("invalid compressed data -- Huffman code > 32 bits");
+ }
+
+ /* Get the number of leaves at each bit length */
+ n = 0;
+ for (len = 1; len <= max_len; len++) {
+ leaves[len] = (int)get_byte();
+ n += leaves[len];
+ }
+ if (n > LITERALS) {
+ error("too many leaves in Huffman tree");
+ }
+ Trace((stderr, "orig_len %ld, max_len %d, leaves %d\n",
+ orig_len, max_len, n));
+ /* There are at least 2 and at most 256 leaves of length max_len.
+ * (Pack arbitrarily rejects empty files and files consisting of
+ * a single byte even repeated.) To fit the last leaf count in a
+ * byte, it is offset by 2. However, the last literal is the EOB
+ * code, and is not transmitted explicitly in the tree, so we must
+ * adjust here by one only.
+ */
+ leaves[max_len]++;
+
+ /* Now read the leaves themselves */
+ base = 0;
+ for (len = 1; len <= max_len; len++) {
+ /* Remember where the literals of this length start in literal[] : */
+ lit_base[len] = base;
+ /* And read the literals: */
+ for (n = leaves[len]; n > 0; n--) {
+ literal[base++] = (uch)get_byte();
+ }
+ }
+ leaves[max_len]++; /* Now include the EOB code in the Huffman tree */
+}
+
+/* ===========================================================================
+ * Build the Huffman tree and the prefix table.
+ */
+local void build_tree()
+{
+ int nodes = 0; /* number of nodes (parents+leaves) at current bit length */
+ int len; /* current bit length */
+ uch *prefixp; /* pointer in prefix_len */
+
+ for (len = max_len; len >= 1; len--) {
+ /* The number of parent nodes at this level is half the total
+ * number of nodes at parent level:
+ */
+ nodes >>= 1;
+ parents[len] = nodes;
+ /* Update lit_base by the appropriate bias to skip the parent nodes
+ * (which are not represented in the literal array):
+ */
+ lit_base[len] -= nodes;
+ /* Restore nodes to be parents+leaves: */
+ nodes += leaves[len];
+ }
+ /* Construct the prefix table, from shortest leaves to longest ones.
+ * The shortest code is all ones, so we start at the end of the table.
+ */
+ peek_bits = MIN(max_len, MAX_PEEK);
+ prefixp = &prefix_len[1<<peek_bits];
+ for (len = 1; len <= peek_bits; len++) {
+ int prefixes = leaves[len] << (peek_bits-len); /* may be 0 */
+ while (prefixes--) *--prefixp = (uch)len;
+ }
+ /* The length of all other codes is unknown: */
+ while (prefixp > prefix_len) *--prefixp = 0;
+}
+
+/* ===========================================================================
+ * Unpack in to out. This routine does not support the old pack format
+ * with magic header \037\037.
+ *
+ * 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 unpack(in, out)
+ int in, out; /* input and output file descriptors */
+{
+ int len; /* Bit length of current code */
+ unsigned eob; /* End Of Block code */
+ register unsigned peek; /* lookahead bits */
+ unsigned peek_mask; /* Mask for peek_bits bits */
+
+ ifd = in;
+ ofd = out;
+
+ read_tree(); /* Read the Huffman tree */
+ build_tree(); /* Build the prefix table */
+ clear_bitbuf(); /* Initialize bit input */
+ peek_mask = (1<<peek_bits)-1;
+
+ /* The eob code is the largest code among all leaves of maximal length: */
+ eob = leaves[max_len]-1;
+ Trace((stderr, "eob %d %x\n", max_len, eob));
+
+ /* Decode the input data: */
+ for (;;) {
+ /* Since eob is the longest code and not shorter than max_len,
+ * we can peek at max_len bits without having the risk of reading
+ * beyond the end of file.
+ */
+ look_bits(peek, peek_bits, peek_mask);
+ len = prefix_len[peek];
+ if (len > 0) {
+ peek >>= peek_bits - len; /* discard the extra bits */
+ } else {
+ /* Code of more than peek_bits bits, we must traverse the tree */
+ ulg mask = peek_mask;
+ len = peek_bits;
+ do {
+ len++, mask = (mask<<1)+1;
+ look_bits(peek, len, mask);
+ } while (peek < (unsigned)parents[len]);
+ /* loop as long as peek is a parent node */
+ }
+ /* At this point, peek is the next complete code, of len bits */
+ if (peek == eob && len == max_len) break; /* end of file? */
+ put_ubyte(literal[peek+lit_base[len]]);
+ Tracev((stderr,"%02d %04x %c\n", len, peek,
+ literal[peek+lit_base[len]]));
+ skip_bits(len);
+ } /* for (;;) */
+
+ flush_window();
+ Trace((stderr, "bytes_out %ld\n", bytes_out));
+ if (orig_len != (ulg)bytes_out) {
+ error("invalid compressed data--length error");
+ }
+ return OK;
+}