- } else {
- errorMsg("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)) {
- errorMsg("invalid compressed data--crc error");
- }
- if (orig_len != (ulg) bytes_out) {
- errorMsg("invalid compressed data--length error");
- }
-
- /* Check if there are more entries in a pkzip file */
- if (pkzip && inptr + 4 < insize && LG(inbuf + inptr) == LOCSIG) {
- WARN((stderr, "has more than one entry--rest ignored\n"));
- }
- ext_header = pkzip = 0; /* for next file */
- return OK;
-}
-
-/* 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.
- */
-
-#include <ctype.h>
-#include <errno.h>
-#include <sys/types.h>
-
-#ifdef HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-#ifndef NO_FCNTL_H
-# include <fcntl.h>
-#endif
-
-#if defined(STDC_HEADERS) || !defined(NO_STDLIB_H)
-# include <stdlib.h>
-#else
-extern int errno;
-#endif
-
-static const ulg crc_32_tab[]; /* crc table, defined below */
-
-/* ===========================================================================
- * 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;
- errno = 0;
- do {
- len = read(ifd, (char *) inbuf + insize, INBUFSIZ - insize);
- if (len == 0 || len == EOF)
- break;
- insize += len;
- } while (insize < INBUFSIZ);
-
- if (insize == 0) {
- if (eof_ok)
- return EOF;
- read_error();
- }
- bytes_in += (ulg) 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;
-
- if (!test_mode)
- write_buf(ofd, (char *) outbuf, outcnt);
- bytes_out += (ulg) 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_mode)
- write_buf(ofd, (char *) window, outcnt);
- bytes_out += (ulg) 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;
-void * buf;
-unsigned cnt;
-{
- unsigned n;
-
- while ((n = write(fd, buf, cnt)) != cnt) {
- if (n == (unsigned) (-1)) {
- write_error();
- }
- cnt -= n;
- buf = (void *) ((char *) buf + n);
- }
-}
-
-#if defined(NO_STRING_H) && !defined(STDC_HEADERS)
-
-/* Provide missing strspn and strcspn functions. */
-
-# ifndef __STDC__
-# define const
-# endif
-
-int strspn (const char *s, const char *accept);
-int strcspn (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 /* NO_STRING_H */
-
-
-/* ========================================================================
- * Error handlers.
- */
-void read_error()
-{
- fprintf(stderr, "\n");
- if (errno != 0) {
- perror("");
- } else {
- fprintf(stderr, "unexpected end of file\n");
- }
- abort_gzip();
-}
-
-void write_error()
-{
- fprintf(stderr, "\n");
- perror("");
- abort_gzip();
-}
-
-
-/* ========================================================================
- * Table of CRC-32's of all single-byte values (made by makecrc.c)
- */
-static const 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
-};
-
-/* 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.
- */
-
-#include <sys/types.h>
-
-#if defined(STDC_HEADERS) || !defined(NO_STDLIB_H)
-# include <stdlib.h>
-#endif
-
-
-#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 (unsigned *, unsigned, unsigned, ush *, ush *,
- struct huft **, int *);
-int huft_free (struct huft *);
-int inflate_codes (struct huft *, struct huft *, int, int);
-int inflate_stored (void);
-int inflate_fixed (void);
-int inflate_dynamic (void);
-int inflate_block (int *);
-int inflate (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() (cc = get_byte(), zdecode(cc), cc)
-#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);
-
-
- /* 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;
- 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 */
- }
-
-
- /* 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);