*
* read_gz interface + associated hacking by Laurence Anderson
*
+ * Fixed huft_build() so decoding end-of-block code does not grab more bits
+ * than necessary (this is required by unzip applet), added inflate_cleanup()
+ * to free leaked bytebuffer memory (used in unzip.c), and some minor style
+ * guide cleanups by Ed Clark
+ *
* 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
/* Copy lengths for literal codes 257..285 */
static const unsigned short cplens[] = {
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
+ 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0
};
/* note: see note #13 above about the 258 in this list. */
/* Extra bits for literal codes 257..285 */
static const unsigned char cplext[] = {
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
+ 5, 5, 5, 0, 99, 99
}; /* 99==invalid */
/* Copy offsets for distance codes 0..29 */
static const unsigned short cpdist[] = {
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
+ 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577
};
/* Extra bits for distance codes */
static const unsigned char cpdext[] = {
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
+ 11, 11, 12, 12, 13, 13
};
/* Tables for deflate from PKZIP's appnote.txt. */
/* initial shift register value */
gunzip_crc = 0xffffffffL;
- gunzip_crc_table = (unsigned int *) malloc(256 * sizeof(unsigned int));
+ gunzip_crc_table = (unsigned int *) xmalloc(256 * sizeof(unsigned int));
/* Compute and print table of CRC's, five per line */
for (i = 0; i < 256; i++) {
table_entry = (table_entry >> 1) ^ poly;
} else {
table_entry >>= 1;
- }
- }
+ }
+ }
gunzip_crc_table[i] = table_entry;
}
}
* 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 char *e, huft_t ** t, int *m)
+int huft_build(unsigned int *b, const unsigned int n,
+ const unsigned int s, const unsigned short *d,
+ const unsigned char *e, huft_t ** t, int *m)
{
- unsigned a; /* counter for codes of length k */
+ 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 */
+ unsigned eob_len; /* length of end-of-block code (value 256) */
+ 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 int k; /* number of bits in current code */
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) */
+ 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 */
+ int ws[BMAX+1]; /* bits decoded stack */
+ register int w; /* bits decoded */
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 */
+ unsigned *xp; /* pointer into x */
+ int y; /* number of dummy codes added */
+ unsigned z; /* number of entries in current table */
+
+ /* Length of EOB code, if any */
+ eob_len = n > 256 ? b[256] : BMAX;
/* Generate counts for each bit length */
- memset((void *) (c), 0, sizeof(c));
+ 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) */
+ 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 */
+ 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;
+ for (j = 1; (c[j] == 0) && (j <= BMAX); j++);
+ k = j; /* minimum code length */
+ for (i = BMAX; (c[i] == 0) && i; i--);
+ g = i; /* maximum code length */
+ *m = (*m < j) ? j : ((*m > i) ? i : *m);
/* 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 */
+ return 2; /* bad input: more codes than bits */
}
}
if ((y -= c[i]) < 0) {
x[1] = j = 0;
p = c + 1;
xp = x + 2;
- while (--i) { /* note that i == g from above */
+ while (--i) { /* note that i == g from above */
*xp++ = (j += *p++);
}
} 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) */
+ x[0] = i = 0; /* first Huffman code is zero */
+ p = v; /* grab values in bit order */
+ h = -1; /* no tables yet--level -1 */
+ w = ws[0] = 0; /* bits decoded */
u[0] = (huft_t *) NULL; /* just to keep compilers happy */
q = (huft_t *) NULL; /* ditto */
- z = 0; /* ditto */
+ z = 0; /* ditto */
/* go through the bit lengths (k already is bits in shortest code) */
for (; k <= g; 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 */
+ while (k > ws[h + 1]) {
+ w = ws[++h];
+
+ /* compute minimum size table less than or equal to *m bits */
+ z = (z = g - w) > *m ? *m : 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 */
+ while (++j < z) { /* try smaller tables up to z bits */
if ((f <<= 1) <= *++xp) {
- break; /* enough codes to use up j bits */
+ break; /* enough codes to use up j bits */
}
- f -= *xp; /* else deduct codes from patterns */
+ f -= *xp; /* else deduct codes from patterns */
}
}
+ j = (w + j > eob_len && w < eob_len) ? eob_len - w : j; /* make EOB code end at table */
z = 1 << j; /* table entries for j-bit table */
+ ws[h+1] = w + j; /* set bits decoded in stack */
/* allocate and link in new table */
q = (huft_t *) xmalloc((z + 1) * sizeof(huft_t));
-
*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 */
+ x[h] = i; /* save pattern for backing up */
+ r.b = (unsigned char) (w - ws[h - 1]); /* 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 & ((1 << w) - 1)) >> ws[h - 1];
+ 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 */
+ 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++ */
+ r.e = (unsigned char) (*p < 256 ? 16 : 15); /* 256 is EOB code */
+ r.v.n = (unsigned short) (*p++); /* simple code is just the value */
} else {
- r.e = (unsigned char) e[*p - s]; /* non-simple--look up in lists */
+ r.e = (unsigned char) e[*p - s]; /* non-simple--look up in lists */
r.v.n = d[*p++ - s];
}
/* backup over finished tables */
while ((i & ((1 << w) - 1)) != x[h]) {
- h--; /* don't need to update q */
- w -= l;
+ w = ws[--h];
}
}
}
+
+ /* return actual size of base table */
+ *m = ws[1];
+
/* Return true (1) if we were given an incomplete table */
return y != 0 && g != 1;
}
bytebuffer_size = 0;
}
+extern void inflate_cleanup(void)
+{
+ free(bytebuffer);
+}
+
extern int inflate_unzip(int in, int out)
{
ssize_t nwrote;
extern int inflate_gunzip(int in, int out)
{
unsigned int stored_crc = 0;
- unsigned char count;
+ unsigned int count;
inflate_unzip(in, out);
projects / oweals / busybox.git / commitdiff