From 027b728d4aafb5cf97abc804944a77b837b0f07f Mon Sep 17 00:00:00 2001 From: Julius Werner Date: Tue, 6 Oct 2015 20:03:53 -0700 Subject: Add support for LZ4 decompression algorithm This patch adds support for LZ4-compressed FIT image contents. This algorithm has a slightly worse compression ration than LZO while being nearly twice as fast to decompress. When loading images from a fast storage medium this usually results in a boot time win. Sandbox-tested only since I don't have a U-Boot development system set up right now. The code was imported unchanged from coreboot where it's proven to work, though. I'm mostly interested in getting this recognized by mkImage for use in a downstream project. Signed-off-by: Julius Werner Acked-by: Simon Glass --- lib/lz4.c | 243 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 243 insertions(+) create mode 100644 lib/lz4.c (limited to 'lib/lz4.c') diff --git a/lib/lz4.c b/lib/lz4.c new file mode 100644 index 0000000000..f518341af5 --- /dev/null +++ b/lib/lz4.c @@ -0,0 +1,243 @@ +/* + LZ4 - Fast LZ compression algorithm + Copyright (C) 2011-2015, Yann Collet. + + SPDX-License-Identifier: BSD-2-Clause + + You can contact the author at : + - LZ4 source repository : https://github.com/Cyan4973/lz4 + - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c +*/ + + +/************************************** +* Reading and writing into memory +**************************************/ + +/* customized version of memcpy, which may overwrite up to 7 bytes beyond dstEnd */ +static void LZ4_wildCopy(void* dstPtr, const void* srcPtr, void* dstEnd) +{ + BYTE* d = (BYTE*)dstPtr; + const BYTE* s = (const BYTE*)srcPtr; + BYTE* e = (BYTE*)dstEnd; + do { LZ4_copy8(d,s); d+=8; s+=8; } while (d oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => decode everything */ + if ((endOnInput) && (unlikely(outputSize==0))) return ((inputSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */ + if ((!endOnInput) && (unlikely(outputSize==0))) return (*ip==0?1:-1); + + + /* Main Loop */ + while (1) + { + unsigned token; + size_t length; + const BYTE* match; + + /* get literal length */ + token = *ip++; + if ((length=(token>>ML_BITS)) == RUN_MASK) + { + unsigned s; + do + { + s = *ip++; + length += s; + } + while (likely((endOnInput)?ip(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) ) + || ((!endOnInput) && (cpy>oend-COPYLENGTH))) + { + if (partialDecoding) + { + if (cpy > oend) goto _output_error; /* Error : write attempt beyond end of output buffer */ + if ((endOnInput) && (ip+length > iend)) goto _output_error; /* Error : read attempt beyond end of input buffer */ + } + else + { + if ((!endOnInput) && (cpy != oend)) goto _output_error; /* Error : block decoding must stop exactly there */ + if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; /* Error : input must be consumed */ + } + memcpy(op, ip, length); + ip += length; + op += length; + break; /* Necessarily EOF, due to parsing restrictions */ + } + LZ4_wildCopy(op, ip, cpy); + ip += length; op = cpy; + + /* get offset */ + match = cpy - LZ4_readLE16(ip); ip+=2; + if ((checkOffset) && (unlikely(match < lowLimit))) goto _output_error; /* Error : offset outside destination buffer */ + + /* get matchlength */ + length = token & ML_MASK; + if (length == ML_MASK) + { + unsigned s; + do + { + if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error; + s = *ip++; + length += s; + } while (s==255); + if ((safeDecode) && unlikely((size_t)(op+length)<(size_t)op)) goto _output_error; /* overflow detection */ + } + length += MINMATCH; + + /* check external dictionary */ + if ((dict==usingExtDict) && (match < lowPrefix)) + { + if (unlikely(op+length > oend-LASTLITERALS)) goto _output_error; /* doesn't respect parsing restriction */ + + if (length <= (size_t)(lowPrefix-match)) + { + /* match can be copied as a single segment from external dictionary */ + match = dictEnd - (lowPrefix-match); + memmove(op, match, length); op += length; + } + else + { + /* match encompass external dictionary and current segment */ + size_t copySize = (size_t)(lowPrefix-match); + memcpy(op, dictEnd - copySize, copySize); + op += copySize; + copySize = length - copySize; + if (copySize > (size_t)(op-lowPrefix)) /* overlap within current segment */ + { + BYTE* const endOfMatch = op + copySize; + const BYTE* copyFrom = lowPrefix; + while (op < endOfMatch) *op++ = *copyFrom++; + } + else + { + memcpy(op, lowPrefix, copySize); + op += copySize; + } + } + continue; + } + + /* copy repeated sequence */ + cpy = op + length; + if (unlikely((op-match)<8)) + { + const size_t dec64 = dec64table[op-match]; + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += dec32table[op-match]; + LZ4_copy4(op+4, match); + op += 8; match -= dec64; + } else { LZ4_copy8(op, match); op+=8; match+=8; } + + if (unlikely(cpy>oend-12)) + { + if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last LASTLITERALS bytes must be literals */ + if (op < oend-8) + { + LZ4_wildCopy(op, match, oend-8); + match += (oend-8) - op; + op = oend-8; + } + while (op