diff options
author | Richard Purdie <rpurdie@rpsys.net> | 2006-06-22 14:47:34 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-22 15:05:58 -0700 |
commit | 4f3865fb57a04db7cca068fed1c15badc064a302 (patch) | |
tree | 4c923c72b6ac9b633c87cc73b55a75c7cfd0f044 /lib/zlib_inflate/infblock.c | |
parent | 4f1bcaf094ccc512c23e10104c05a6f8e5b7a9e4 (diff) | |
download | op-kernel-dev-4f3865fb57a04db7cca068fed1c15badc064a302.zip op-kernel-dev-4f3865fb57a04db7cca068fed1c15badc064a302.tar.gz |
[PATCH] zlib_inflate: Upgrade library code to a recent version
Upgrade the zlib_inflate implementation in the kernel from a patched
version 1.1.3/4 to a patched 1.2.3.
The code in the kernel is about seven years old and I noticed that the
external zlib library's inflate performance was significantly faster (~50%)
than the code in the kernel on ARM (and faster again on x86_32).
For comparison the newer deflate code is 20% slower on ARM and 50% slower
on x86_32 but gives an approx 1% compression ratio improvement. I don't
consider this to be an improvement for kernel use so have no plans to
change the zlib_deflate code.
Various changes have been made to the zlib code in the kernel, the most
significant being the extra functions/flush option used by ppp_deflate.
This update reimplements the features PPP needs to ensure it continues to
work.
This code has been tested on ARM under both JFFS2 (with zlib compression
enabled) and ppp_deflate and on x86_32. JFFS2 sees an approx. 10% real
world file read speed improvement.
This patch also removes ZLIB_VERSION as it no longer has a correct value.
We don't need version checks anyway as the kernel's module handling will
take care of that for us. This removal is also more in keeping with the
zlib author's wishes (http://www.zlib.net/zlib_faq.html#faq24) and I've
added something to the zlib.h header to note its a modified version.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Joern Engel <joern@wh.fh-wedel.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'lib/zlib_inflate/infblock.c')
-rw-r--r-- | lib/zlib_inflate/infblock.c | 365 |
1 files changed, 0 insertions, 365 deletions
diff --git a/lib/zlib_inflate/infblock.c b/lib/zlib_inflate/infblock.c deleted file mode 100644 index c16cdef..0000000 --- a/lib/zlib_inflate/infblock.c +++ /dev/null @@ -1,365 +0,0 @@ -/* infblock.c -- interpret and process block types to last block - * Copyright (C) 1995-1998 Mark Adler - * For conditions of distribution and use, see copyright notice in zlib.h - */ - -#include <linux/zutil.h> -#include "infblock.h" -#include "inftrees.h" -#include "infcodes.h" -#include "infutil.h" - -struct inflate_codes_state; - -/* simplify the use of the inflate_huft type with some defines */ -#define exop word.what.Exop -#define bits word.what.Bits - -/* Table for deflate from PKZIP's appnote.txt. */ -static const uInt 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}; - -/* - 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. Similarily, 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. - */ - - -void zlib_inflate_blocks_reset( - inflate_blocks_statef *s, - z_streamp z, - uLong *c -) -{ - if (c != NULL) - *c = s->check; - if (s->mode == CODES) - zlib_inflate_codes_free(s->sub.decode.codes, z); - s->mode = TYPE; - s->bitk = 0; - s->bitb = 0; - s->read = s->write = s->window; - if (s->checkfn != NULL) - z->adler = s->check = (*s->checkfn)(0L, NULL, 0); -} - -inflate_blocks_statef *zlib_inflate_blocks_new( - z_streamp z, - check_func c, - uInt w -) -{ - inflate_blocks_statef *s; - - s = &WS(z)->working_blocks_state; - s->hufts = WS(z)->working_hufts; - s->window = WS(z)->working_window; - s->end = s->window + w; - s->checkfn = c; - s->mode = TYPE; - zlib_inflate_blocks_reset(s, z, NULL); - return s; -} - - -int zlib_inflate_blocks( - inflate_blocks_statef *s, - z_streamp z, - int r -) -{ - uInt t; /* temporary storage */ - uLong b; /* bit buffer */ - uInt k; /* bits in bit buffer */ - Byte *p; /* input data pointer */ - uInt n; /* bytes available there */ - Byte *q; /* output window write pointer */ - uInt m; /* bytes to end of window or read pointer */ - - /* copy input/output information to locals (UPDATE macro restores) */ - LOAD - - /* process input based on current state */ - while (1) switch (s->mode) - { - case TYPE: - NEEDBITS(3) - t = (uInt)b & 7; - s->last = t & 1; - switch (t >> 1) - { - case 0: /* stored */ - DUMPBITS(3) - t = k & 7; /* go to byte boundary */ - DUMPBITS(t) - s->mode = LENS; /* get length of stored block */ - break; - case 1: /* fixed */ - { - uInt bl, bd; - inflate_huft *tl, *td; - - zlib_inflate_trees_fixed(&bl, &bd, &tl, &td, s->hufts, z); - s->sub.decode.codes = zlib_inflate_codes_new(bl, bd, tl, td, z); - if (s->sub.decode.codes == NULL) - { - r = Z_MEM_ERROR; - LEAVE - } - } - DUMPBITS(3) - s->mode = CODES; - break; - case 2: /* dynamic */ - DUMPBITS(3) - s->mode = TABLE; - break; - case 3: /* illegal */ - DUMPBITS(3) - s->mode = B_BAD; - z->msg = (char*)"invalid block type"; - r = Z_DATA_ERROR; - LEAVE - } - break; - case LENS: - NEEDBITS(32) - if ((((~b) >> 16) & 0xffff) != (b & 0xffff)) - { - s->mode = B_BAD; - z->msg = (char*)"invalid stored block lengths"; - r = Z_DATA_ERROR; - LEAVE - } - s->sub.left = (uInt)b & 0xffff; - b = k = 0; /* dump bits */ - s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE); - break; - case STORED: - if (n == 0) - LEAVE - NEEDOUT - t = s->sub.left; - if (t > n) t = n; - if (t > m) t = m; - memcpy(q, p, t); - p += t; n -= t; - q += t; m -= t; - if ((s->sub.left -= t) != 0) - break; - s->mode = s->last ? DRY : TYPE; - break; - case TABLE: - NEEDBITS(14) - s->sub.trees.table = t = (uInt)b & 0x3fff; -#ifndef PKZIP_BUG_WORKAROUND - if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) - { - s->mode = B_BAD; - z->msg = (char*)"too many length or distance symbols"; - r = Z_DATA_ERROR; - LEAVE - } -#endif - { - s->sub.trees.blens = WS(z)->working_blens; - } - DUMPBITS(14) - s->sub.trees.index = 0; - s->mode = BTREE; - case BTREE: - while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10)) - { - NEEDBITS(3) - s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7; - DUMPBITS(3) - } - while (s->sub.trees.index < 19) - s->sub.trees.blens[border[s->sub.trees.index++]] = 0; - s->sub.trees.bb = 7; - t = zlib_inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb, - &s->sub.trees.tb, s->hufts, z); - if (t != Z_OK) - { - r = t; - if (r == Z_DATA_ERROR) - s->mode = B_BAD; - LEAVE - } - s->sub.trees.index = 0; - s->mode = DTREE; - case DTREE: - while (t = s->sub.trees.table, - s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)) - { - inflate_huft *h; - uInt i, j, c; - - t = s->sub.trees.bb; - NEEDBITS(t) - h = s->sub.trees.tb + ((uInt)b & zlib_inflate_mask[t]); - t = h->bits; - c = h->base; - if (c < 16) - { - DUMPBITS(t) - s->sub.trees.blens[s->sub.trees.index++] = c; - } - else /* c == 16..18 */ - { - i = c == 18 ? 7 : c - 14; - j = c == 18 ? 11 : 3; - NEEDBITS(t + i) - DUMPBITS(t) - j += (uInt)b & zlib_inflate_mask[i]; - DUMPBITS(i) - i = s->sub.trees.index; - t = s->sub.trees.table; - if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || - (c == 16 && i < 1)) - { - s->mode = B_BAD; - z->msg = (char*)"invalid bit length repeat"; - r = Z_DATA_ERROR; - LEAVE - } - c = c == 16 ? s->sub.trees.blens[i - 1] : 0; - do { - s->sub.trees.blens[i++] = c; - } while (--j); - s->sub.trees.index = i; - } - } - s->sub.trees.tb = NULL; - { - uInt bl, bd; - inflate_huft *tl, *td; - inflate_codes_statef *c; - - bl = 9; /* must be <= 9 for lookahead assumptions */ - bd = 6; /* must be <= 9 for lookahead assumptions */ - t = s->sub.trees.table; - t = zlib_inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), - s->sub.trees.blens, &bl, &bd, &tl, &td, - s->hufts, z); - if (t != Z_OK) - { - if (t == (uInt)Z_DATA_ERROR) - s->mode = B_BAD; - r = t; - LEAVE - } - if ((c = zlib_inflate_codes_new(bl, bd, tl, td, z)) == NULL) - { - r = Z_MEM_ERROR; - LEAVE - } - s->sub.decode.codes = c; - } - s->mode = CODES; - case CODES: - UPDATE - if ((r = zlib_inflate_codes(s, z, r)) != Z_STREAM_END) - return zlib_inflate_flush(s, z, r); - r = Z_OK; - zlib_inflate_codes_free(s->sub.decode.codes, z); - LOAD - if (!s->last) - { - s->mode = TYPE; - break; - } - s->mode = DRY; - case DRY: - FLUSH - if (s->read != s->write) - LEAVE - s->mode = B_DONE; - case B_DONE: - r = Z_STREAM_END; - LEAVE - case B_BAD: - r = Z_DATA_ERROR; - LEAVE - default: - r = Z_STREAM_ERROR; - LEAVE - } -} - - -int zlib_inflate_blocks_free( - inflate_blocks_statef *s, - z_streamp z -) -{ - zlib_inflate_blocks_reset(s, z, NULL); - return Z_OK; -} - - -#if 0 -void zlib_inflate_set_dictionary( - inflate_blocks_statef *s, - const Byte *d, - uInt n -) -{ - memcpy(s->window, d, n); - s->read = s->write = s->window + n; -} -#endif /* 0 */ - - -/* Returns true if inflate is currently at the end of a block generated - * by Z_SYNC_FLUSH or Z_FULL_FLUSH. - * IN assertion: s != NULL - */ -#if 0 -int zlib_inflate_blocks_sync_point( - inflate_blocks_statef *s -) -{ - return s->mode == LENS; -} -#endif /* 0 */ |