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Diffstat (limited to 'libbb/unzip.c')
| -rw-r--r-- | libbb/unzip.c | 1040 |
1 files changed, 1040 insertions, 0 deletions
diff --git a/libbb/unzip.c b/libbb/unzip.c new file mode 100644 index 0000000..3826316 --- /dev/null +++ b/libbb/unzip.c @@ -0,0 +1,1040 @@ +/* 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 <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; /* 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}; + + /* initial shift register value */ + crc = 0xffffffffL; + 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); + + /* 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; + ungetc((bb << bk), in_file); + } + + /* 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); + exit_code = 1; + } else if (res != 0) { + error_msg("invalid compressed data--format violated"); + exit_code = 1; + } + + } else { + error_msg("internal error, invalid method"); + exit_code = 1; + } + + /* 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 (!exit_code && (unsigned int)((buf[0] | (buf[1] << 8)) |((buf[2] | (buf[3] << 8)) << 16)) != (crc ^ 0xffffffffL)) { + error_msg("invalid compressed data--crc error"); + exit_code = 1; + } + /* Validate decompression - size */ + if (!exit_code && ((buf[4] | (buf[5] << 8)) |((buf[6] | (buf[7] << 8)) << 16)) != (unsigned long) bytes_out) { + error_msg("invalid compressed data--length error"); + exit_code = 1; + } + + free(window); + free(crc_table); + + return exit_code; +} + +/* + * 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); +} |