busybox/archival/libunarchive/decompress_unzip.c
Eric Andersen 044228d5ec This is vodz' latest patch. Sorry it took so long...
1) ping cleanup (compile fix from this patch already applied).
    2) traceroute call not spare ntohl() now (and reduce size);
    3) Fix for functions not declared static in insmod, ash, vi and mount.
    4) a more simple API cmdedit :))
    5) adds "stopped jobs" warning to ash on Ctrl-D and fixes "ignoreeof" option
    6) reduce exporting library function index->strchr (traceroute), bzero->memset (syslogd)
2001-07-17 01:12:36 +00:00

1027 lines
28 KiB
C

/* vi: set sw=4 ts=4: */
/*
* gunzip implementation for busybox
*
* Based on GNU gzip v1.2.4 Copyright (C) 1992-1993 Jean-loup Gailly.
*
* Originally adjusted for busybox by Sven Rudolph <sr1@inf.tu-dresden.de>
* based on gzip sources
*
* Adjusted further by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
* to support files as well as stdin/stdout, and to generally behave itself wrt
* command line handling.
*
* General cleanup to better adhere to the style guide and make use of standard
* busybox functions by Glenn McGrath <bug1@optushome.com.au>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*
* 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.
*/
#if 0
static char *license_msg[] = {
" Copyright (C) 1992-1993 Jean-loup Gailly",
" This program is free software; you can redistribute it and/or modify",
" it under the terms of the GNU General Public License as published by",
" the Free Software Foundation; either version 2, or (at your option)",
" any later version.",
"",
" This program is distributed in the hope that it will be useful,",
" but WITHOUT ANY WARRANTY; without even the implied warranty of",
" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the",
" GNU General Public License for more details.",
"",
" You should have received a copy of the GNU General Public License",
" along with this program; if not, write to the Free Software",
" Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.",
0
};
#endif
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include "libbb.h"
static FILE *in_file, *out_file;
/* these are freed by gz_close */
static unsigned char *window;
static unsigned long *crc_table;
static unsigned long crc = 0xffffffffL; /* shift register contents */
/* Return codes from gzip */
static const int ERROR = 1;
/*
* window size--must be a power of two, and
* at least 32K for zip's deflate method
*/
static const int WSIZE = 0x8000;
/* If BMAX needs to be larger than 16, then h and x[] should be ulg. */
static const int BMAX = 16; /* maximum bit length of any code (16 for explode) */
static const int N_MAX = 288; /* maximum number of codes in any set */
static long bytes_out; /* number of output bytes */
static unsigned long outcnt; /* bytes in output buffer */
static unsigned hufts; /* track memory usage */
static unsigned long bb; /* bit buffer */
static unsigned bk; /* bits in bit buffer */
typedef struct huft_s {
unsigned char e; /* number of extra bits or operation */
unsigned char b; /* number of bits in this code or subcode */
union {
unsigned short n; /* literal, length base, or distance base */
struct huft_s *t; /* pointer to next level of table */
} v;
} huft_t;
static const unsigned short mask_bits[] = {
0x0000,
0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
};
//static int error_number = 0;
/* ========================================================================
* Signal and error handler.
*/
static void abort_gzip()
{
error_msg("gzip aborted\n");
exit(ERROR);
}
static void make_crc_table()
{
unsigned long table_entry; /* crc shift register */
unsigned long poly = 0; /* polynomial exclusive-or pattern */
int i; /* counter for all possible eight bit values */
int k; /* byte being shifted into crc apparatus */
/* terms of polynomial defining this crc (except x^32): */
static int p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
crc_table = (unsigned long *) malloc(256 * sizeof(unsigned long));
/* Make exclusive-or pattern from polynomial (0xedb88320) */
for (i = 0; i < sizeof(p)/sizeof(int); i++)
poly |= 1L << (31 - p[i]);
/* Compute and print table of CRC's, five per line */
for (i = 0; i < 256; i++) {
table_entry = i;
/* The idea to initialize the register with the byte instead of
* zero was stolen from Haruhiko Okumura's ar002
*/
for (k = 8; k; k--) {
table_entry = table_entry & 1 ? (table_entry >> 1) ^ poly : table_entry >> 1;
}
crc_table[i]=table_entry;
}
}
/* ===========================================================================
* Write the output window window[0..outcnt-1] and update crc and bytes_out.
* (Used for the decompressed data only.)
*/
static void flush_window(void)
{
int n;
if (outcnt == 0)
return;
for (n = 0; n < outcnt; n++) {
crc = crc_table[((int) crc ^ (window[n])) & 0xff] ^ (crc >> 8);
}
if (fwrite(window, 1, outcnt, out_file) != outcnt) {
error_msg_and_die("Couldnt write");
}
bytes_out += (unsigned long) outcnt;
outcnt = 0;
}
/*
* 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.
* t: table to free
*/
static int huft_free(huft_t *t)
{
huft_t *p, *q;
/* Go through linked list, freeing from the malloced (t[-1]) address. */
p = t;
while (p != (huft_t *) NULL) {
q = (--p)->v.t;
free((char *) p);
p = q;
}
return 0;
}
/* 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.
*
* b: code lengths in bits (all assumed <= BMAX)
* n: number of codes (assumed <= N_MAX)
* s: number of simple-valued codes (0..s-1)
* d: list of base values for non-simple codes
* e: list of extra bits for non-simple codes
* t: result: starting table
* m: maximum lookup bits, returns actual
*/
static int huft_build(unsigned int *b, const unsigned int n, const unsigned int s,
const unsigned short *d, const unsigned short *e, huft_t **t, int *m)
{
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 huft_t *q; /* points to current table */
huft_t r; /* table entry for structure assignment */
huft_t *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 */
memset ((void *)(c), 0, sizeof(c));
p = b;
i = n;
do {
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 = (huft_t *) 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] = (huft_t *) NULL; /* just to keep compilers happy */
q = (huft_t *) 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 = (huft_t *) xmalloc((z + 1) * sizeof(huft_t))) == 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)) = 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 = (unsigned char) l; /* bits to dump before this table */
r.e = (unsigned char) (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 = (unsigned char) (k - w);
if (p >= v + n)
r.e = 99; /* out of values--invalid code */
else if (*p < s) {
r.e = (unsigned char) (*p < 256 ? 16 : 15); /* 256 is end-of-block code */
r.v.n = (unsigned short) (*p); /* simple code is just the value */
p++; /* one compiler does not like *p++ */
} else {
r.e = (unsigned char) 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;
}
/*
* inflate (decompress) the codes in a deflated (compressed) block.
* Return an error code or zero if it all goes ok.
*
* tl, td: literal/length and distance decoder tables
* bl, bd: number of bits decoded by tl[] and td[]
*/
static int inflate_codes(huft_t *tl, huft_t *td, int bl, int bd)
{
register unsigned long e; /* table entry flag/number of extra bits */
unsigned long n, d; /* length and index for copy */
unsigned long w; /* current window position */
huft_t *t; /* pointer to table entry */
unsigned ml, md; /* masks for bl and bd bits */
register unsigned long 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 = outcnt; /* 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 */
while (k < (unsigned) bl) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
if ((e = (t = tl + ((unsigned) b & ml))->e) > 16)
do {
if (e == 99) {
return 1;
}
b >>= t->b;
k -= t->b;
e -= 16;
while (k < e) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
} while ((e = (t = t->v.t + ((unsigned) b & mask_bits[e]))->e) > 16);
b >>= t->b;
k -= t->b;
if (e == 16) { /* then it's a literal */
window[w++] = (unsigned char) t->v.n;
if (w == WSIZE) {
outcnt=(w),
flush_window();
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 */
while (k < e) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
n = t->v.n + ((unsigned) b & mask_bits[e]);
b >>= e;
k -= e;
/* decode distance of block to copy */
while (k < (unsigned) bd) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
if ((e = (t = td + ((unsigned) b & md))->e) > 16)
do {
if (e == 99)
return 1;
b >>= t->b;
k -= t->b;
e -= 16;
while (k < e) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
} while ((e = (t = t->v.t + ((unsigned) b & mask_bits[e]))->e) > 16);
b >>= t->b;
k -= t->b;
while (k < e) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
d = w - t->v.n - ((unsigned) b & mask_bits[e]);
b >>= e;
k -= e;
/* 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(window + w, window + d, e);
w += e;
d += e;
} else /* do it slow to avoid memcpy() overlap */
#endif /* !NOMEMCPY */
do {
window[w++] = window[d++];
} while (--e);
if (w == WSIZE) {
outcnt=(w),
flush_window();
w = 0;
}
} while (n);
}
}
/* restore the globals from the locals */
outcnt = w; /* restore global window pointer */
bb = b; /* restore global bit buffer */
bk = k;
/* done */
return 0;
}
/*
* decompress an inflated block
* e: last block flag
*
* GLOBAL VARIABLES: bb, kk,
*/
static int inflate_block(int *e)
{
unsigned t; /* block type */
register unsigned long b; /* bit buffer */
register unsigned k; /* number of bits in bit buffer */
static unsigned short 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 unsigned short 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 unsigned short 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 unsigned short 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
};
/* make local bit buffer */
b = bb;
k = bk;
/* read in last block bit */
while (k < 1) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
*e = (int) b & 1;
b >>= 1;
k -= 1;
/* read in block type */
while (k < 2) {
b |= ((unsigned long)fgetc(in_file)) << k;
k += 8;
}
t = (unsigned) b & 3;
b >>= 2;
k -= 2;
/* restore the global bit buffer */
bb = b;
bk = k;
/* inflate that block type */
switch (t) {
case 0: /* Inflate stored */
{
unsigned long n; /* number of bytes in block */
unsigned long w; /* current window position */
register unsigned long b_stored; /* bit buffer */
register unsigned long k_stored; /* number of bits in bit buffer */
/* make local copies of globals */
b_stored = bb; /* initialize bit buffer */
k_stored = bk;
w = outcnt; /* initialize window position */
/* go to byte boundary */
n = k_stored & 7;
b_stored >>= n;
k_stored -= n;
/* get the length and its complement */
while (k_stored < 16) {
b_stored |= ((unsigned long)fgetc(in_file)) << k_stored;
k_stored += 8;
}
n = ((unsigned) b_stored & 0xffff);
b_stored >>= 16;
k_stored -= 16;
while (k_stored < 16) {
b_stored |= ((unsigned long)fgetc(in_file)) << k_stored;
k_stored += 8;
}
if (n != (unsigned) ((~b_stored) & 0xffff)) {
return 1; /* error in compressed data */
}
b_stored >>= 16;
k_stored -= 16;
/* read and output the compressed data */
while (n--) {
while (k_stored < 8) {
b_stored |= ((unsigned long)fgetc(in_file)) << k_stored;
k_stored += 8;
}
window[w++] = (unsigned char) b_stored;
if (w == (unsigned long)WSIZE) {
outcnt=(w),
flush_window();
w = 0;
}
b_stored >>= 8;
k_stored -= 8;
}
/* restore the globals from the locals */
outcnt = w; /* restore global window pointer */
bb = b_stored; /* restore global bit buffer */
bk = k_stored;
return 0;
}
case 1: /* 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 */
huft_t *tl; /* literal/length code table */
huft_t *td; /* distance code table */
int bl; /* lookup bits for tl */
int bd; /* lookup bits for td */
unsigned int 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;
}
case 2: /* Inflate dynamic */
{
/* 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
};
int dbits = 6; /* bits in base distance lookup table */
int lbits = 9; /* bits in base literal/length lookup table */
int i; /* temporary variables */
unsigned j;
unsigned l; /* last length */
unsigned m; /* mask for bit lengths table */
unsigned n; /* number of lengths to get */
huft_t *tl; /* literal/length code table */
huft_t *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 */
unsigned ll[286 + 30]; /* literal/length and distance code lengths */
register unsigned long b_dynamic; /* bit buffer */
register unsigned k_dynamic; /* number of bits in bit buffer */
/* make local bit buffer */
b_dynamic = bb;
k_dynamic = bk;
/* read in table lengths */
while (k_dynamic < 5) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
nl = 257 + ((unsigned) b_dynamic & 0x1f); /* number of literal/length codes */
b_dynamic >>= 5;
k_dynamic -= 5;
while (k_dynamic < 5) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
nd = 1 + ((unsigned) b_dynamic & 0x1f); /* number of distance codes */
b_dynamic >>= 5;
k_dynamic -= 5;
while (k_dynamic < 4) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
nb = 4 + ((unsigned) b_dynamic & 0xf); /* number of bit length codes */
b_dynamic >>= 4;
k_dynamic -= 4;
if (nl > 286 || nd > 30) {
return 1; /* bad lengths */
}
/* read in bit-length-code lengths */
for (j = 0; j < nb; j++) {
while (k_dynamic < 3) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
ll[border[j]] = (unsigned) b_dynamic & 7;
b_dynamic >>= 3;
k_dynamic -= 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) {
while (k_dynamic < (unsigned) bl) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
j = (td = tl + ((unsigned) b_dynamic & m))->b;
b_dynamic >>= j;
k_dynamic -= 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 */
while (k_dynamic < 2) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
j = 3 + ((unsigned) b_dynamic & 3);
b_dynamic >>= 2;
k_dynamic -= 2;
if ((unsigned) i + j > n) {
return 1;
}
while (j--) {
ll[i++] = l;
}
} else if (j == 17) { /* 3 to 10 zero length codes */
while (k_dynamic < 3) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
j = 3 + ((unsigned) b_dynamic & 7);
b_dynamic >>= 3;
k_dynamic -= 3;
if ((unsigned) i + j > n) {
return 1;
}
while (j--) {
ll[i++] = 0;
}
l = 0;
} else { /* j == 18: 11 to 138 zero length codes */
while (k_dynamic < 7) {
b_dynamic |= ((unsigned long)fgetc(in_file)) << k_dynamic;
k_dynamic += 8;
}
j = 11 + ((unsigned) b_dynamic & 0x7f);
b_dynamic >>= 7;
k_dynamic -= 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_dynamic;
bk = k_dynamic;
/* 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) {
error_msg("Incomplete literal tree");
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) {
error_msg("incomplete distance tree");
huft_free(td);
}
huft_free(tl);
return i; /* incomplete code set */
}
/* 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;
}
default:
/* bad block type */
return 2;
}
}
/*
* decompress an inflated entry
*
* GLOBAL VARIABLES: outcnt, bk, bb, hufts, inptr
*/
static int inflate()
{
int e; /* last block flag */
int r; /* result code */
unsigned h = 0; /* maximum struct huft's malloc'ed */
/* initialize window, bit buffer */
outcnt = 0;
bk = 0;
bb = 0;
/* decompress until the last block */
do {
hufts = 0;
if ((r = inflate_block(&e)) != 0) {
return r;
}
if (hufts > h) {
h = hufts;
}
} while (!e);
/* flush out window */
flush_window();
/* return success */
return 0;
}
/* ===========================================================================
* 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.
* in, out: input and output file descriptors
*/
extern int unzip(FILE *l_in_file, FILE *l_out_file)
{
const int extra_field = 0x04; /* bit 2 set: extra field present */
const int orig_name = 0x08; /* bit 3 set: original file name present */
const int comment = 0x10; /* bit 4 set: file comment present */
unsigned char buf[8]; /* extended local header */
unsigned char flags; /* compression flags */
char magic[2]; /* magic header */
int method;
typedef void (*sig_type) (int);
int exit_code=0; /* program exit code */
int i;
in_file = l_in_file;
out_file = l_out_file;
if (signal(SIGINT, SIG_IGN) != SIG_IGN) {
(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
/* Allocate all global buffers (for DYN_ALLOC option) */
window = xmalloc((size_t)(((2L*WSIZE)+1L)*sizeof(unsigned char)));
outcnt = 0;
bytes_out = 0L;
magic[0] = fgetc(in_file);
magic[1] = fgetc(in_file);
/* Magic header for gzip files, 1F 8B = \037\213 */
if (memcmp(magic, "\037\213", 2) != 0) {
error_msg("Invalid gzip magic");
return EXIT_FAILURE;
}
method = (int) fgetc(in_file);
if (method != 8) {
error_msg("unknown method %d -- get newer version of gzip", method);
exit_code = 1;
return -1;
}
flags = (unsigned char) fgetc(in_file);
/* Ignore time stamp(4), extra flags(1), OS type(1) */
for (i = 0; i < 6; i++)
fgetc(in_file);
if ((flags & extra_field) != 0) {
size_t extra;
extra = fgetc(in_file);
extra += fgetc(in_file) << 8;
for (i = 0; i < extra; i++)
fgetc(in_file);
}
/* Discard original name if any */
if ((flags & orig_name) != 0) {
while (fgetc(in_file) != 0); /* null */
}
/* Discard file comment if any */
if ((flags & comment) != 0) {
while (fgetc(in_file) != 0); /* null */
}
if (method < 0) {
printf("it failed\n");
return(exit_code); /* error message already emitted */
}
make_crc_table();
/* Decompress */
if (method == 8) {
int res = inflate();
if (res == 3) {
error_msg(memory_exhausted);
} else if (res != 0) {
error_msg("invalid compressed data--format violated");
}
} else {
error_msg("internal error, invalid method");
}
/* Get the crc and original length
* crc32 (see algorithm.doc)
* uncompressed input size modulo 2^32
*/
fread(buf, 1, 8, in_file);
/* Validate decompression - crc */
if ((unsigned int)((buf[0] | (buf[1] << 8)) |((buf[2] | (buf[3] << 8)) << 16)) != (crc ^ 0xffffffffL)) {
error_msg("invalid compressed data--crc error");
}
/* Validate decompression - size */
if (((buf[4] | (buf[5] << 8)) |((buf[6] | (buf[7] << 8)) << 16)) != (unsigned long) bytes_out) {
error_msg("invalid compressed data--length error");
}
free(window);
free(crc_table);
return 0;
}
/*
* This needs access to global variables wondow and crc_table, so its not in its own file.
*/
extern void gz_close(int gunzip_pid)
{
if (kill(gunzip_pid, SIGTERM) == -1) {
error_msg_and_die("*** Couldnt kill old gunzip process *** aborting");
}
if (waitpid(gunzip_pid, NULL, 0) == -1) {
printf("Couldnt wait ?");
}
free(window);
free(crc_table);
}