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-rw-r--r--grub-core/fs/zfs/zfs_lz4.c285
1 files changed, 285 insertions, 0 deletions
diff --git a/grub-core/fs/zfs/zfs_lz4.c b/grub-core/fs/zfs/zfs_lz4.c
new file mode 100644
index 0000000..5453822
--- /dev/null
+++ b/grub-core/fs/zfs/zfs_lz4.c
@@ -0,0 +1,285 @@
+/*
+ * LZ4 - Fast LZ compression algorithm
+ * Header File
+ * Copyright (C) 2011-2013, Yann Collet.
+ * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You can contact the author at :
+ * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
+ * - LZ4 source repository : http://code.google.com/p/lz4/
+ */
+
+#include <grub/err.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/types.h>
+
+static int LZ4_uncompress_unknownOutputSize(const char *source, char *dest,
+ int isize, int maxOutputSize);
+
+/*
+ * CPU Feature Detection
+ */
+
+/* 32 or 64 bits ? */
+#if (GRUB_CPU_SIZEOF_VOID_P == 8)
+#define LZ4_ARCH64 1
+#else
+#define LZ4_ARCH64 0
+#endif
+
+/*
+ * Compiler Options
+ */
+
+
+#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+
+#if (GCC_VERSION >= 302) || (defined (__INTEL_COMPILER) && __INTEL_COMPILER >= 800) || defined(__clang__)
+#define expect(expr, value) (__builtin_expect((expr), (value)))
+#else
+#define expect(expr, value) (expr)
+#endif
+
+#define likely(expr) expect((expr) != 0, 1)
+#define unlikely(expr) expect((expr) != 0, 0)
+
+/* Basic types */
+#define BYTE grub_uint8_t
+#define U16 grub_uint16_t
+#define U32 grub_uint32_t
+#define S32 grub_int32_t
+#define U64 grub_uint64_t
+
+typedef struct _U16_S {
+ U16 v;
+} GRUB_PACKED U16_S;
+typedef struct _U32_S {
+ U32 v;
+} GRUB_PACKED U32_S;
+typedef struct _U64_S {
+ U64 v;
+} GRUB_PACKED U64_S;
+
+#define A64(x) (((U64_S *)(x))->v)
+#define A32(x) (((U32_S *)(x))->v)
+#define A16(x) (((U16_S *)(x))->v)
+
+/*
+ * Constants
+ */
+#define MINMATCH 4
+
+#define COPYLENGTH 8
+#define LASTLITERALS 5
+
+#define ML_BITS 4
+#define ML_MASK ((1U<<ML_BITS)-1)
+#define RUN_BITS (8-ML_BITS)
+#define RUN_MASK ((1U<<RUN_BITS)-1)
+
+/*
+ * Architecture-specific macros
+ */
+#if LZ4_ARCH64
+#define STEPSIZE 8
+#define UARCH U64
+#define AARCH A64
+#define LZ4_COPYSTEP(s, d) A64(d) = A64(s); d += 8; s += 8;
+#define LZ4_COPYPACKET(s, d) LZ4_COPYSTEP(s, d)
+#define LZ4_SECURECOPY(s, d, e) if (d < e) LZ4_WILDCOPY(s, d, e)
+#define HTYPE U32
+#define INITBASE(base) const BYTE* const base = ip
+#else
+#define STEPSIZE 4
+#define UARCH U32
+#define AARCH A32
+#define LZ4_COPYSTEP(s, d) A32(d) = A32(s); d += 4; s += 4;
+#define LZ4_COPYPACKET(s, d) LZ4_COPYSTEP(s, d); LZ4_COPYSTEP(s, d);
+#define LZ4_SECURECOPY LZ4_WILDCOPY
+#define HTYPE const BYTE*
+#define INITBASE(base) const int base = 0
+#endif
+
+#define LZ4_READ_LITTLEENDIAN_16(d, s, p) { d = (s) - grub_le_to_cpu16 (A16 (p)); }
+#define LZ4_WRITE_LITTLEENDIAN_16(p, v) { A16(p) = grub_cpu_to_le16 (v); p += 2; }
+
+/* Macros */
+#define LZ4_WILDCOPY(s, d, e) do { LZ4_COPYPACKET(s, d) } while (d < e);
+
+/* Decompression functions */
+grub_err_t
+lz4_decompress(void *s_start, void *d_start, grub_size_t s_len, grub_size_t d_len);
+
+grub_err_t
+lz4_decompress(void *s_start, void *d_start, grub_size_t s_len, grub_size_t d_len)
+{
+ const BYTE *src = s_start;
+ U32 bufsiz = (src[0] << 24) | (src[1] << 16) | (src[2] << 8) |
+ src[3];
+
+ /* invalid compressed buffer size encoded at start */
+ if (bufsiz + 4 > s_len)
+ return grub_error(GRUB_ERR_BAD_FS,"lz4 decompression failed.");
+
+ /*
+ * Returns 0 on success (decompression function returned non-negative)
+ * and appropriate error on failure (decompression function returned negative).
+ */
+ return (LZ4_uncompress_unknownOutputSize((char*)s_start + 4, d_start, bufsiz,
+ d_len) < 0)?grub_error(GRUB_ERR_BAD_FS,"lz4 decompression failed."):0;
+}
+
+static int
+LZ4_uncompress_unknownOutputSize(const char *source,
+ char *dest, int isize, int maxOutputSize)
+{
+ /* Local Variables */
+ const BYTE * ip = (const BYTE *) source;
+ const BYTE *const iend = ip + isize;
+ const BYTE * ref;
+
+ BYTE * op = (BYTE *) dest;
+ BYTE *const oend = op + maxOutputSize;
+ BYTE *cpy;
+
+ grub_size_t dec[] = { 0, 3, 2, 3, 0, 0, 0, 0 };
+
+ /* Main Loop */
+ while (ip < iend) {
+ BYTE token;
+ int length;
+
+ /* get runlength */
+ token = *ip++;
+ if ((length = (token >> ML_BITS)) == RUN_MASK) {
+ int s = 255;
+ while ((ip < iend) && (s == 255)) {
+ s = *ip++;
+ length += s;
+ }
+ }
+ /* copy literals */
+ if ((grub_addr_t) length > ~(grub_addr_t)op)
+ goto _output_error;
+ cpy = op + length;
+ if ((cpy > oend - COPYLENGTH) ||
+ (ip + length > iend - COPYLENGTH)) {
+ if (cpy > oend)
+ /*
+ * Error: request to write beyond destination
+ * buffer.
+ */
+ goto _output_error;
+ if (ip + length > iend)
+ /*
+ * Error : request to read beyond source
+ * buffer.
+ */
+ goto _output_error;
+ grub_memcpy(op, ip, length);
+ op += length;
+ ip += length;
+ if (ip < iend)
+ /* Error : LZ4 format violation */
+ goto _output_error;
+ /* Necessarily EOF, due to parsing restrictions. */
+ break;
+ }
+ LZ4_WILDCOPY(ip, op, cpy);
+ ip -= (op - cpy);
+ op = cpy;
+
+ /* get offset */
+ LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip);
+ ip += 2;
+ if (ref < (BYTE * const) dest)
+ /*
+ * Error: offset creates reference outside of
+ * destination buffer.
+ */
+ goto _output_error;
+
+ /* get matchlength */
+ if ((length = (token & ML_MASK)) == ML_MASK) {
+ while (ip < iend) {
+ int s = *ip++;
+ length += s;
+ if (s == 255)
+ continue;
+ break;
+ }
+ }
+ /* copy repeated sequence */
+ if unlikely(op - ref < STEPSIZE) {
+#if LZ4_ARCH64
+ grub_size_t dec2table[] = { 0, 0, 0, -1, 0, 1, 2, 3 };
+ grub_size_t dec2 = dec2table[op - ref];
+#else
+ const int dec2 = 0;
+#endif
+ *op++ = *ref++;
+ *op++ = *ref++;
+ *op++ = *ref++;
+ *op++ = *ref++;
+ ref -= dec[op - ref];
+ A32(op) = A32(ref);
+ op += STEPSIZE - 4;
+ ref -= dec2;
+ } else {
+ LZ4_COPYSTEP(ref, op);
+ }
+ cpy = op + length - (STEPSIZE - 4);
+ if (cpy > oend - COPYLENGTH) {
+ if (cpy > oend)
+ /*
+ * Error: request to write outside of
+ * destination buffer.
+ */
+ goto _output_error;
+ LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH));
+ while (op < cpy)
+ *op++ = *ref++;
+ op = cpy;
+ if (op == oend)
+ /*
+ * Check EOF (should never happen, since last
+ * 5 bytes are supposed to be literals).
+ */
+ break;
+ continue;
+ }
+ LZ4_SECURECOPY(ref, op, cpy);
+ op = cpy; /* correction */
+ }
+
+ /* end of decoding */
+ return (int)(((char *)op) - dest);
+
+ /* write overflow error detected */
+ _output_error:
+ return (int)(-(((char *)ip) - source));
+}