1a6f561b4SSašo Kiselkov /*
2a6f561b4SSašo Kiselkov * LZ4 - Fast LZ compression algorithm
3a6f561b4SSašo Kiselkov * Header File
4a6f561b4SSašo Kiselkov * Copyright (C) 2011-2013, Yann Collet.
5a6f561b4SSašo Kiselkov * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
6a6f561b4SSašo Kiselkov *
7a6f561b4SSašo Kiselkov * Redistribution and use in source and binary forms, with or without
8a6f561b4SSašo Kiselkov * modification, are permitted provided that the following conditions are
9a6f561b4SSašo Kiselkov * met:
10a6f561b4SSašo Kiselkov *
11a6f561b4SSašo Kiselkov * * Redistributions of source code must retain the above copyright
12a6f561b4SSašo Kiselkov * notice, this list of conditions and the following disclaimer.
13a6f561b4SSašo Kiselkov * * Redistributions in binary form must reproduce the above
14a6f561b4SSašo Kiselkov * copyright notice, this list of conditions and the following disclaimer
15a6f561b4SSašo Kiselkov * in the documentation and/or other materials provided with the
16a6f561b4SSašo Kiselkov * distribution.
17a6f561b4SSašo Kiselkov *
18a6f561b4SSašo Kiselkov * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19a6f561b4SSašo Kiselkov * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20a6f561b4SSašo Kiselkov * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21a6f561b4SSašo Kiselkov * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22a6f561b4SSašo Kiselkov * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23a6f561b4SSašo Kiselkov * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24a6f561b4SSašo Kiselkov * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25a6f561b4SSašo Kiselkov * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26a6f561b4SSašo Kiselkov * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27a6f561b4SSašo Kiselkov * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28a6f561b4SSašo Kiselkov * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29a6f561b4SSašo Kiselkov *
30a6f561b4SSašo Kiselkov * You can contact the author at :
31a6f561b4SSašo Kiselkov * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
32a6f561b4SSašo Kiselkov * - LZ4 source repository : http://code.google.com/p/lz4/
33a6f561b4SSašo Kiselkov */
34a6f561b4SSašo Kiselkov
35a6f561b4SSašo Kiselkov #include "fsys_zfs.h"
36a6f561b4SSašo Kiselkov #include <string.h>
37a6f561b4SSašo Kiselkov
38a6f561b4SSašo Kiselkov static int LZ4_uncompress_unknownOutputSize(const char *source, char *dest,
39a6f561b4SSašo Kiselkov int isize, int maxOutputSize);
40a6f561b4SSašo Kiselkov
41a6f561b4SSašo Kiselkov int
lz4_decompress(void * s_start,void * d_start,size_t s_len,size_t d_len)42a6f561b4SSašo Kiselkov lz4_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len)
43a6f561b4SSašo Kiselkov {
44a6f561b4SSašo Kiselkov const uint8_t *src = s_start;
45a6f561b4SSašo Kiselkov uint32_t bufsiz = (src[0] << 24) | (src[1] << 16) | (src[2] << 8) |
46a6f561b4SSašo Kiselkov src[3];
47a6f561b4SSašo Kiselkov
48a6f561b4SSašo Kiselkov /* invalid compressed buffer size encoded at start */
49a6f561b4SSašo Kiselkov if (bufsiz + 4 > s_len)
50a6f561b4SSašo Kiselkov return (1);
51a6f561b4SSašo Kiselkov
52a6f561b4SSašo Kiselkov /*
53a6f561b4SSašo Kiselkov * Returns 0 on success (decompression function returned non-negative)
54a6f561b4SSašo Kiselkov * and non-zero on failure (decompression function returned negative).
55a6f561b4SSašo Kiselkov */
56a6f561b4SSašo Kiselkov return (LZ4_uncompress_unknownOutputSize(s_start + 4, d_start, bufsiz,
57a6f561b4SSašo Kiselkov d_len) < 0);
58a6f561b4SSašo Kiselkov }
59a6f561b4SSašo Kiselkov
60a6f561b4SSašo Kiselkov /*
61a6f561b4SSašo Kiselkov * CPU Feature Detection
62a6f561b4SSašo Kiselkov */
63a6f561b4SSašo Kiselkov
64a6f561b4SSašo Kiselkov /* 32 or 64 bits ? */
65a6f561b4SSašo Kiselkov #if (defined(__x86_64__) || defined(__x86_64) || defined(__amd64__) || \
66a6f561b4SSašo Kiselkov defined(__amd64) || defined(__ppc64__) || defined(_WIN64) || \
67a6f561b4SSašo Kiselkov defined(__LP64__) || defined(_LP64))
68a6f561b4SSašo Kiselkov #define LZ4_ARCH64 1
69a6f561b4SSašo Kiselkov #else
70a6f561b4SSašo Kiselkov #define LZ4_ARCH64 0
71a6f561b4SSašo Kiselkov #endif
72a6f561b4SSašo Kiselkov
73a6f561b4SSašo Kiselkov /*
74a6f561b4SSašo Kiselkov * Little Endian or Big Endian?
75a6f561b4SSašo Kiselkov * Note: overwrite the below #define if you know your architecture endianess.
76a6f561b4SSašo Kiselkov */
77a6f561b4SSašo Kiselkov #if (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || \
78a6f561b4SSašo Kiselkov defined(_BIG_ENDIAN) || defined(_ARCH_PPC) || defined(__PPC__) || \
79a6f561b4SSašo Kiselkov defined(__PPC) || defined(PPC) || defined(__powerpc__) || \
80a6f561b4SSašo Kiselkov defined(__powerpc) || defined(powerpc) || \
81a6f561b4SSašo Kiselkov ((defined(__BYTE_ORDER__)&&(__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))))
82a6f561b4SSašo Kiselkov #define LZ4_BIG_ENDIAN 1
83a6f561b4SSašo Kiselkov #else
84a6f561b4SSašo Kiselkov /*
85a6f561b4SSašo Kiselkov * Little Endian assumed. PDP Endian and other very rare endian format
86a6f561b4SSašo Kiselkov * are unsupported.
87a6f561b4SSašo Kiselkov */
88a6f561b4SSašo Kiselkov #endif
89a6f561b4SSašo Kiselkov
90a6f561b4SSašo Kiselkov /*
91a6f561b4SSašo Kiselkov * Compiler Options
92a6f561b4SSašo Kiselkov */
93a6f561b4SSašo Kiselkov #if __STDC_VERSION__ >= 199901L /* C99 */
94a6f561b4SSašo Kiselkov /* "restrict" is a known keyword */
95a6f561b4SSašo Kiselkov #else
96a6f561b4SSašo Kiselkov /* Disable restrict */
97a6f561b4SSašo Kiselkov #define restrict
98a6f561b4SSašo Kiselkov #endif
99a6f561b4SSašo Kiselkov
100a6f561b4SSašo Kiselkov #define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
101a6f561b4SSašo Kiselkov
102a6f561b4SSašo Kiselkov #define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) \
103a6f561b4SSašo Kiselkov | (((x) & 0xffu) << 8)))
104a6f561b4SSašo Kiselkov
105a6f561b4SSašo Kiselkov #if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__)
106a6f561b4SSašo Kiselkov #define expect(expr, value) (__builtin_expect((expr), (value)))
107a6f561b4SSašo Kiselkov #else
108a6f561b4SSašo Kiselkov #define expect(expr, value) (expr)
109a6f561b4SSašo Kiselkov #endif
110a6f561b4SSašo Kiselkov
111a6f561b4SSašo Kiselkov #define likely(expr) expect((expr) != 0, 1)
112a6f561b4SSašo Kiselkov #define unlikely(expr) expect((expr) != 0, 0)
113a6f561b4SSašo Kiselkov
114a6f561b4SSašo Kiselkov /* Basic types */
115a6f561b4SSašo Kiselkov #define BYTE uint8_t
116a6f561b4SSašo Kiselkov #define U16 uint16_t
117a6f561b4SSašo Kiselkov #define U32 uint32_t
118a6f561b4SSašo Kiselkov #define S32 int32_t
119a6f561b4SSašo Kiselkov #define U64 uint64_t
120a6f561b4SSašo Kiselkov
121a6f561b4SSašo Kiselkov typedef struct _U16_S {
122a6f561b4SSašo Kiselkov U16 v;
123a6f561b4SSašo Kiselkov } U16_S;
124a6f561b4SSašo Kiselkov typedef struct _U32_S {
125a6f561b4SSašo Kiselkov U32 v;
126a6f561b4SSašo Kiselkov } U32_S;
127a6f561b4SSašo Kiselkov typedef struct _U64_S {
128a6f561b4SSašo Kiselkov U64 v;
129a6f561b4SSašo Kiselkov } U64_S;
130a6f561b4SSašo Kiselkov
131a6f561b4SSašo Kiselkov #define A64(x) (((U64_S *)(x))->v)
132a6f561b4SSašo Kiselkov #define A32(x) (((U32_S *)(x))->v)
133a6f561b4SSašo Kiselkov #define A16(x) (((U16_S *)(x))->v)
134a6f561b4SSašo Kiselkov
135a6f561b4SSašo Kiselkov /*
136a6f561b4SSašo Kiselkov * Constants
137a6f561b4SSašo Kiselkov */
138a6f561b4SSašo Kiselkov #define MINMATCH 4
139a6f561b4SSašo Kiselkov
140a6f561b4SSašo Kiselkov #define COPYLENGTH 8
141a6f561b4SSašo Kiselkov #define LASTLITERALS 5
142a6f561b4SSašo Kiselkov
143a6f561b4SSašo Kiselkov #define ML_BITS 4
144a6f561b4SSašo Kiselkov #define ML_MASK ((1U<<ML_BITS)-1)
145a6f561b4SSašo Kiselkov #define RUN_BITS (8-ML_BITS)
146a6f561b4SSašo Kiselkov #define RUN_MASK ((1U<<RUN_BITS)-1)
147a6f561b4SSašo Kiselkov
148a6f561b4SSašo Kiselkov /*
149a6f561b4SSašo Kiselkov * Architecture-specific macros
150a6f561b4SSašo Kiselkov */
151a6f561b4SSašo Kiselkov #if LZ4_ARCH64
152a6f561b4SSašo Kiselkov #define STEPSIZE 8
153a6f561b4SSašo Kiselkov #define UARCH U64
154a6f561b4SSašo Kiselkov #define AARCH A64
155a6f561b4SSašo Kiselkov #define LZ4_COPYSTEP(s, d) A64(d) = A64(s); d += 8; s += 8;
156a6f561b4SSašo Kiselkov #define LZ4_COPYPACKET(s, d) LZ4_COPYSTEP(s, d)
157a6f561b4SSašo Kiselkov #define LZ4_SECURECOPY(s, d, e) if (d < e) LZ4_WILDCOPY(s, d, e)
158a6f561b4SSašo Kiselkov #define HTYPE U32
159a6f561b4SSašo Kiselkov #define INITBASE(base) const BYTE* const base = ip
160a6f561b4SSašo Kiselkov #else
161a6f561b4SSašo Kiselkov #define STEPSIZE 4
162a6f561b4SSašo Kiselkov #define UARCH U32
163a6f561b4SSašo Kiselkov #define AARCH A32
164a6f561b4SSašo Kiselkov #define LZ4_COPYSTEP(s, d) A32(d) = A32(s); d += 4; s += 4;
165a6f561b4SSašo Kiselkov #define LZ4_COPYPACKET(s, d) LZ4_COPYSTEP(s, d); LZ4_COPYSTEP(s, d);
166a6f561b4SSašo Kiselkov #define LZ4_SECURECOPY LZ4_WILDCOPY
167a6f561b4SSašo Kiselkov #define HTYPE const BYTE*
168a6f561b4SSašo Kiselkov #define INITBASE(base) const int base = 0
169a6f561b4SSašo Kiselkov #endif
170a6f561b4SSašo Kiselkov
171a6f561b4SSašo Kiselkov #if (defined(LZ4_BIG_ENDIAN) && !defined(BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE))
172a6f561b4SSašo Kiselkov #define LZ4_READ_LITTLEENDIAN_16(d, s, p) \
173a6f561b4SSašo Kiselkov { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; }
174a6f561b4SSašo Kiselkov #define LZ4_WRITE_LITTLEENDIAN_16(p, i) \
175a6f561b4SSašo Kiselkov { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p += 2; }
176a6f561b4SSašo Kiselkov #else
177a6f561b4SSašo Kiselkov #define LZ4_READ_LITTLEENDIAN_16(d, s, p) { d = (s) - A16(p); }
178a6f561b4SSašo Kiselkov #define LZ4_WRITE_LITTLEENDIAN_16(p, v) { A16(p) = v; p += 2; }
179a6f561b4SSašo Kiselkov #endif
180a6f561b4SSašo Kiselkov
181a6f561b4SSašo Kiselkov /* Macros */
182a6f561b4SSašo Kiselkov #define LZ4_WILDCOPY(s, d, e) do { LZ4_COPYPACKET(s, d) } while (d < e);
183a6f561b4SSašo Kiselkov
184a6f561b4SSašo Kiselkov /* Decompression functions */
185a6f561b4SSašo Kiselkov
186a6f561b4SSašo Kiselkov static int
LZ4_uncompress_unknownOutputSize(const char * source,char * dest,int isize,int maxOutputSize)187a6f561b4SSašo Kiselkov LZ4_uncompress_unknownOutputSize(const char *source,
188a6f561b4SSašo Kiselkov char *dest, int isize, int maxOutputSize)
189a6f561b4SSašo Kiselkov {
190a6f561b4SSašo Kiselkov /* Local Variables */
191a6f561b4SSašo Kiselkov const BYTE *restrict ip = (const BYTE *) source;
192a6f561b4SSašo Kiselkov const BYTE *const iend = ip + isize;
193a6f561b4SSašo Kiselkov const BYTE *restrict ref;
194a6f561b4SSašo Kiselkov
195a6f561b4SSašo Kiselkov BYTE *restrict op = (BYTE *) dest;
196a6f561b4SSašo Kiselkov BYTE *const oend = op + maxOutputSize;
197a6f561b4SSašo Kiselkov BYTE *cpy;
198a6f561b4SSašo Kiselkov
199a6f561b4SSašo Kiselkov size_t dec[] = { 0, 3, 2, 3, 0, 0, 0, 0 };
200a6f561b4SSašo Kiselkov
201a6f561b4SSašo Kiselkov /* Main Loop */
202a6f561b4SSašo Kiselkov while (ip < iend) {
203a6f561b4SSašo Kiselkov BYTE token;
204a6f561b4SSašo Kiselkov int length;
205a6f561b4SSašo Kiselkov
206a6f561b4SSašo Kiselkov /* get runlength */
207a6f561b4SSašo Kiselkov token = *ip++;
208a6f561b4SSašo Kiselkov if ((length = (token >> ML_BITS)) == RUN_MASK) {
209a6f561b4SSašo Kiselkov int s = 255;
210a6f561b4SSašo Kiselkov while ((ip < iend) && (s == 255)) {
211a6f561b4SSašo Kiselkov s = *ip++;
212a6f561b4SSašo Kiselkov length += s;
213a6f561b4SSašo Kiselkov }
214a6f561b4SSašo Kiselkov }
215a6f561b4SSašo Kiselkov /* copy literals */
216a6f561b4SSašo Kiselkov cpy = op + length;
217*58d07180SDan McDonald /* CORNER-CASE: cpy might overflow. */
218*58d07180SDan McDonald if (cpy < op)
219*58d07180SDan McDonald goto _output_error; /* cpy was overflowed, bail! */
220a6f561b4SSašo Kiselkov if ((cpy > oend - COPYLENGTH) ||
221a6f561b4SSašo Kiselkov (ip + length > iend - COPYLENGTH)) {
222a6f561b4SSašo Kiselkov if (cpy > oend)
223a6f561b4SSašo Kiselkov /*
224a6f561b4SSašo Kiselkov * Error: request to write beyond destination
225a6f561b4SSašo Kiselkov * buffer.
226a6f561b4SSašo Kiselkov */
227a6f561b4SSašo Kiselkov goto _output_error;
228a6f561b4SSašo Kiselkov if (ip + length > iend)
229a6f561b4SSašo Kiselkov /*
230a6f561b4SSašo Kiselkov * Error : request to read beyond source
231a6f561b4SSašo Kiselkov * buffer.
232a6f561b4SSašo Kiselkov */
233a6f561b4SSašo Kiselkov goto _output_error;
234a6f561b4SSašo Kiselkov memcpy(op, ip, length);
235a6f561b4SSašo Kiselkov op += length;
236a6f561b4SSašo Kiselkov ip += length;
237a6f561b4SSašo Kiselkov if (ip < iend)
238a6f561b4SSašo Kiselkov /* Error : LZ4 format violation */
239a6f561b4SSašo Kiselkov goto _output_error;
240a6f561b4SSašo Kiselkov /* Necessarily EOF, due to parsing restrictions. */
241a6f561b4SSašo Kiselkov break;
242a6f561b4SSašo Kiselkov }
243a6f561b4SSašo Kiselkov LZ4_WILDCOPY(ip, op, cpy);
244a6f561b4SSašo Kiselkov ip -= (op - cpy);
245a6f561b4SSašo Kiselkov op = cpy;
246a6f561b4SSašo Kiselkov
247a6f561b4SSašo Kiselkov /* get offset */
248a6f561b4SSašo Kiselkov LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip);
249a6f561b4SSašo Kiselkov ip += 2;
250a6f561b4SSašo Kiselkov if (ref < (BYTE * const) dest)
251a6f561b4SSašo Kiselkov /*
252a6f561b4SSašo Kiselkov * Error: offset creates reference outside of
253a6f561b4SSašo Kiselkov * destination buffer.
254a6f561b4SSašo Kiselkov */
255a6f561b4SSašo Kiselkov goto _output_error;
256a6f561b4SSašo Kiselkov
257a6f561b4SSašo Kiselkov /* get matchlength */
258a6f561b4SSašo Kiselkov if ((length = (token & ML_MASK)) == ML_MASK) {
259a6f561b4SSašo Kiselkov while (ip < iend) {
260a6f561b4SSašo Kiselkov int s = *ip++;
261a6f561b4SSašo Kiselkov length += s;
262a6f561b4SSašo Kiselkov if (s == 255)
263a6f561b4SSašo Kiselkov continue;
264a6f561b4SSašo Kiselkov break;
265a6f561b4SSašo Kiselkov }
266a6f561b4SSašo Kiselkov }
267a6f561b4SSašo Kiselkov /* copy repeated sequence */
268a6f561b4SSašo Kiselkov if unlikely(op - ref < STEPSIZE) {
269a6f561b4SSašo Kiselkov #if LZ4_ARCH64
270a6f561b4SSašo Kiselkov size_t dec2table[] = { 0, 0, 0, -1, 0, 1, 2, 3 };
271a6f561b4SSašo Kiselkov size_t dec2 = dec2table[op - ref];
272a6f561b4SSašo Kiselkov #else
273a6f561b4SSašo Kiselkov const int dec2 = 0;
274a6f561b4SSašo Kiselkov #endif
275a6f561b4SSašo Kiselkov *op++ = *ref++;
276a6f561b4SSašo Kiselkov *op++ = *ref++;
277a6f561b4SSašo Kiselkov *op++ = *ref++;
278a6f561b4SSašo Kiselkov *op++ = *ref++;
279a6f561b4SSašo Kiselkov ref -= dec[op - ref];
280a6f561b4SSašo Kiselkov A32(op) = A32(ref);
281a6f561b4SSašo Kiselkov op += STEPSIZE - 4;
282a6f561b4SSašo Kiselkov ref -= dec2;
283a6f561b4SSašo Kiselkov } else {
284a6f561b4SSašo Kiselkov LZ4_COPYSTEP(ref, op);
285a6f561b4SSašo Kiselkov }
286a6f561b4SSašo Kiselkov cpy = op + length - (STEPSIZE - 4);
287a6f561b4SSašo Kiselkov if (cpy > oend - COPYLENGTH) {
288a6f561b4SSašo Kiselkov if (cpy > oend)
289a6f561b4SSašo Kiselkov /*
290a6f561b4SSašo Kiselkov * Error: request to write outside of
291a6f561b4SSašo Kiselkov * destination buffer.
292a6f561b4SSašo Kiselkov */
293a6f561b4SSašo Kiselkov goto _output_error;
294a6f561b4SSašo Kiselkov LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
295a6f561b4SSašo Kiselkov while (op < cpy)
296a6f561b4SSašo Kiselkov *op++ = *ref++;
297a6f561b4SSašo Kiselkov op = cpy;
298a6f561b4SSašo Kiselkov if (op == oend)
299a6f561b4SSašo Kiselkov /*
300a6f561b4SSašo Kiselkov * Check EOF (should never happen, since last
301a6f561b4SSašo Kiselkov * 5 bytes are supposed to be literals).
302a6f561b4SSašo Kiselkov */
303a6f561b4SSašo Kiselkov break;
304a6f561b4SSašo Kiselkov continue;
305a6f561b4SSašo Kiselkov }
306a6f561b4SSašo Kiselkov LZ4_SECURECOPY(ref, op, cpy);
307a6f561b4SSašo Kiselkov op = cpy; /* correction */
308a6f561b4SSašo Kiselkov }
309a6f561b4SSašo Kiselkov
310a6f561b4SSašo Kiselkov /* end of decoding */
311a6f561b4SSašo Kiselkov return (int)(((char *)op) - dest);
312a6f561b4SSašo Kiselkov
313a6f561b4SSašo Kiselkov /* write overflow error detected */
314a6f561b4SSašo Kiselkov _output_error:
315a6f561b4SSašo Kiselkov return (int)(-(((char *)ip) - source));
316a6f561b4SSašo Kiselkov }
317