-From a276288db937088d00b975ad9c36278fa46c8cf7 Mon Sep 17 00:00:00 2001
+From 308795a7713ca6fcd468b60fba9a2fca99cee6a0 Mon Sep 17 00:00:00 2001
From: Nick Terrell <terrelln@fb.com>
-Date: Fri, 4 Aug 2017 12:47:29 -0700
-Subject: [PATCH v4 0/5] Add xxhash and zstd modules
+Date: Tue, 8 Aug 2017 19:20:25 -0700
+Subject: [PATCH v5 0/5] Add xxhash and zstd modules
Hi all,
- Fix minor linter warnings (3/5, 4/5)
- Add crypto patch (5/5)
+v4 -> v5:
+- Fix rare compression bug from upstream commit 308047eb5d (2/5)
+- Fix bug introduced in v3 when working around the gcc-7 bug (2/5)
+- Fix ZSTD_DStream initialization code in squashfs (4/5)
+- Fix patch documentation for patches written by Sean Purcell (4/5)
+
Nick Terrell (5):
lib: Add xxhash module
lib: Add zstd modules
fs/squashfs/decompressor.c | 7 +
fs/squashfs/decompressor.h | 4 +
fs/squashfs/squashfs_fs.h | 1 +
- fs/squashfs/zstd_wrapper.c | 149 ++
+ fs/squashfs/zstd_wrapper.c | 151 ++
include/linux/xxhash.h | 236 +++
include/linux/zstd.h | 1157 +++++++++++++++
include/uapi/linux/btrfs.h | 8 +-
lib/xxhash.c | 500 +++++++
lib/zstd/Makefile | 18 +
lib/zstd/bitstream.h | 374 +++++
- lib/zstd/compress.c | 3479 ++++++++++++++++++++++++++++++++++++++++++++
+ lib/zstd/compress.c | 3484 ++++++++++++++++++++++++++++++++++++++++++++
lib/zstd/decompress.c | 2528 ++++++++++++++++++++++++++++++++
- lib/zstd/entropy_common.c | 243 ++++
+ lib/zstd/entropy_common.c | 243 +++
lib/zstd/error_private.h | 53 +
lib/zstd/fse.h | 575 ++++++++
lib/zstd/fse_compress.c | 795 ++++++++++
lib/zstd/huf_decompress.c | 960 ++++++++++++
lib/zstd/mem.h | 151 ++
lib/zstd/zstd_common.c | 75 +
- lib/zstd/zstd_internal.h | 250 ++++
+ lib/zstd/zstd_internal.h | 263 ++++
lib/zstd/zstd_opt.h | 1014 +++++++++++++
- 44 files changed, 14736 insertions(+), 12 deletions(-)
+ 44 files changed, 14756 insertions(+), 12 deletions(-)
create mode 100644 crypto/zstd.c
create mode 100644 fs/btrfs/zstd.c
create mode 100644 fs/squashfs/zstd_wrapper.c
-From 587f1ba6e78cc5b0d3e26971290aef36ff66f378 Mon Sep 17 00:00:00 2001
+From a4b1ffb6e89bbccd519f9afa0910635668436105 Mon Sep 17 00:00:00 2001
From: Nick Terrell <terrelln@fb.com>
Date: Mon, 17 Jul 2017 17:07:18 -0700
-Subject: [PATCH v4 1/5] lib: Add xxhash module
+Subject: [PATCH v5 1/5] lib: Add xxhash module
Adds xxhash kernel module with xxh32 and xxh64 hashes. xxhash is an
extremely fast non-cryptographic hash algorithm for checksumming.
-From c7f952ce985f652fe1f2c9266f39cd87b470fd8a Mon Sep 17 00:00:00 2001
+From b7f044163968d724be55bf4841fd80babe036dc2 Mon Sep 17 00:00:00 2001
From: Nick Terrell <terrelln@fb.com>
Date: Mon, 17 Jul 2017 17:08:19 -0700
-Subject: [PATCH v4 2/5] lib: Add zstd modules
+Subject: [PATCH v5 2/5] lib: Add zstd modules
Add zstd compression and decompression kernel modules.
zstd offers a wide varity of compression speed and quality trade-offs.
v3 -> v4:
- Fix minor compiler warnings
+v4 -> v5:
+- Fix rare compression bug from upstream commit 308047eb5d
+- Fix bug introduced in v3 when working around the gcc-7 bug
+
include/linux/zstd.h | 1157 +++++++++++++++
lib/Kconfig | 8 +
lib/Makefile | 2 +
lib/zstd/Makefile | 18 +
lib/zstd/bitstream.h | 374 +++++
- lib/zstd/compress.c | 3479 +++++++++++++++++++++++++++++++++++++++++++++
+ lib/zstd/compress.c | 3484 +++++++++++++++++++++++++++++++++++++++++++++
lib/zstd/decompress.c | 2528 ++++++++++++++++++++++++++++++++
lib/zstd/entropy_common.c | 243 ++++
lib/zstd/error_private.h | 53 +
lib/zstd/huf_decompress.c | 960 +++++++++++++
lib/zstd/mem.h | 151 ++
lib/zstd/zstd_common.c | 75 +
- lib/zstd/zstd_internal.h | 250 ++++
+ lib/zstd/zstd_internal.h | 263 ++++
lib/zstd/zstd_opt.h | 1014 +++++++++++++
- 19 files changed, 12996 insertions(+)
+ 19 files changed, 13014 insertions(+)
create mode 100644 include/linux/zstd.h
create mode 100644 lib/zstd/Makefile
create mode 100644 lib/zstd/bitstream.h
+#endif /* BITSTREAM_H_MODULE */
diff --git a/lib/zstd/compress.c b/lib/zstd/compress.c
new file mode 100644
-index 0000000..d60ab7d
+index 0000000..f9166cf
--- /dev/null
+++ b/lib/zstd/compress.c
-@@ -0,0 +1,3479 @@
+@@ -0,0 +1,3484 @@
+/**
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ mlCodeTable[seqStorePtr->longLengthPos] = MaxML;
+}
+
-+ZSTD_STATIC size_t ZSTD_compressSequences(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, size_t srcSize)
++ZSTD_STATIC size_t ZSTD_compressSequences_internal(ZSTD_CCtx *zc, void *dst, size_t dstCapacity)
+{
+ const int longOffsets = zc->params.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
+ const seqStore_t *seqStorePtr = &(zc->seqStore);
+ else
+ op[0] = 0xFF, ZSTD_writeLE16(op + 1, (U16)(nbSeq - LONGNBSEQ)), op += 3;
+ if (nbSeq == 0)
-+ goto _check_compressibility;
++ return op - ostart;
+
+ /* seqHead : flags for FSE encoding type */
+ seqHead = op++;
+ op += streamSize;
+ }
+ }
++ return op - ostart;
++}
+
-+/* check compressibility */
-+_check_compressibility:
-+ {
-+ size_t const minGain = ZSTD_minGain(srcSize);
-+ size_t const maxCSize = srcSize - minGain;
-+ if ((size_t)(op - ostart) >= maxCSize) {
-+ zc->flagStaticHufTable = HUF_repeat_none;
-+ return 0;
-+ }
-+ }
++ZSTD_STATIC size_t ZSTD_compressSequences(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, size_t srcSize)
++{
++ size_t const cSize = ZSTD_compressSequences_internal(zc, dst, dstCapacity);
++ size_t const minGain = ZSTD_minGain(srcSize);
++ size_t const maxCSize = srcSize - minGain;
++ /* If the srcSize <= dstCapacity, then there is enough space to write a
++ * raw uncompressed block. Since we ran out of space, the block must not
++ * be compressible, so fall back to a raw uncompressed block.
++ */
++ int const uncompressibleError = cSize == ERROR(dstSize_tooSmall) && srcSize <= dstCapacity;
++ int i;
+
-+ /* confirm repcodes */
-+ {
-+ int i;
-+ for (i = 0; i < ZSTD_REP_NUM; i++)
-+ zc->rep[i] = zc->repToConfirm[i];
++ if (ZSTD_isError(cSize) && !uncompressibleError)
++ return cSize;
++ if (cSize >= maxCSize || uncompressibleError) {
++ zc->flagStaticHufTable = HUF_repeat_none;
++ return 0;
+ }
-+
-+ return op - ostart;
++ /* confirm repcodes */
++ for (i = 0; i < ZSTD_REP_NUM; i++)
++ zc->rep[i] = zc->repToConfirm[i];
++ return cSize;
+}
+
+/*! ZSTD_storeSeq() :
+}
diff --git a/lib/zstd/zstd_internal.h b/lib/zstd/zstd_internal.h
new file mode 100644
-index 0000000..44e8f100
+index 0000000..1a79fab
--- /dev/null
+++ b/lib/zstd/zstd_internal.h
-@@ -0,0 +1,250 @@
+@@ -0,0 +1,263 @@
+/**
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * All rights reserved.
+#define WILDCOPY_OVERLENGTH 8
+ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
+{
-+ if (length > 0)
-+ memcpy(dst, src, length);
++ const BYTE* ip = (const BYTE*)src;
++ BYTE* op = (BYTE*)dst;
++ BYTE* const oend = op + length;
++ /* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388.
++ * Avoid the bad case where the loop only runs once by handling the
++ * special case separately. This doesn't trigger the bug because it
++ * doesn't involve pointer/integer overflow.
++ */
++ if (length <= 8)
++ return ZSTD_copy8(dst, src);
++ do {
++ ZSTD_copy8(op, ip);
++ op += 8;
++ ip += 8;
++ } while (op < oend);
+}
+
+/*-*******************************************
-From 6ade5bc08dcfa2bce2b4801e47edf783dcb7ca43 Mon Sep 17 00:00:00 2001
+From 8a9dddfbf6551afea73911e367dd4be64d62b9fd Mon Sep 17 00:00:00 2001
From: Nick Terrell <terrelln@fb.com>
Date: Mon, 17 Jul 2017 17:08:39 -0700
-Subject: [PATCH v4 3/5] btrfs: Add zstd support
+Subject: [PATCH v5 3/5] btrfs: Add zstd support
Add zstd compression and decompression support to BtrFS. zstd at its
fastest level compresses almost as well as zlib, while offering much
-From 6e1c54639deca96465b973ad80e34ff7fc789573 Mon Sep 17 00:00:00 2001
+From 46bf8f6d30d6ddf2446c110f122482b5e5e16933 Mon Sep 17 00:00:00 2001
From: Sean Purcell <me@seanp.xyz>
Date: Mon, 17 Jul 2017 17:08:59 -0700
-Subject: [PATCH v4 4/5] squashfs: Add zstd support
+Subject: [PATCH v5 4/5] squashfs: Add zstd support
Add zstd compression and decompression support to SquashFS. zstd is a
great fit for SquashFS because it can compress at ratios approaching xz,
v3 -> v4:
- Fix minor linter warnings
+v4 -> v5:
+- Fix ZSTD_DStream initialization code in squashfs
+- Fix patch documentation to reflect that Sean Purcell is the author
+
fs/squashfs/Kconfig | 14 +++++
fs/squashfs/Makefile | 1 +
fs/squashfs/decompressor.c | 7 +++
fs/squashfs/decompressor.h | 4 ++
fs/squashfs/squashfs_fs.h | 1 +
- fs/squashfs/zstd_wrapper.c | 149 +++++++++++++++++++++++++++++++++++++++++++++
- 6 files changed, 176 insertions(+)
+ fs/squashfs/zstd_wrapper.c | 151 +++++++++++++++++++++++++++++++++++++++++++++
+ 6 files changed, 178 insertions(+)
create mode 100644 fs/squashfs/zstd_wrapper.c
diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig
__le32 s_magic;
diff --git a/fs/squashfs/zstd_wrapper.c b/fs/squashfs/zstd_wrapper.c
new file mode 100644
-index 0000000..d70efa8
+index 0000000..eeaabf8
--- /dev/null
+++ b/fs/squashfs/zstd_wrapper.c
-@@ -0,0 +1,149 @@
+@@ -0,0 +1,151 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+struct workspace {
+ void *mem;
+ size_t mem_size;
++ size_t window_size;
+};
+
+static void *zstd_init(struct squashfs_sb_info *msblk, void *buff)
+
+ if (wksp == NULL)
+ goto failed;
-+ wksp->mem_size = ZSTD_DStreamWorkspaceBound(max_t(size_t,
-+ msblk->block_size, SQUASHFS_METADATA_SIZE));
++ wksp->window_size = max_t(size_t,
++ msblk->block_size, SQUASHFS_METADATA_SIZE);
++ wksp->mem_size = ZSTD_DStreamWorkspaceBound(wksp->window_size);
+ wksp->mem = vmalloc(wksp->mem_size);
+ if (wksp->mem == NULL)
+ goto failed;
+ ZSTD_inBuffer in_buf = { NULL, 0, 0 };
+ ZSTD_outBuffer out_buf = { NULL, 0, 0 };
+
-+ stream = ZSTD_initDStream(wksp->mem_size, wksp->mem, wksp->mem_size);
++ stream = ZSTD_initDStream(wksp->window_size, wksp->mem, wksp->mem_size);
+
+ if (!stream) {
+ ERROR("Failed to initialize zstd decompressor\n");
-From a276288db937088d00b975ad9c36278fa46c8cf7 Mon Sep 17 00:00:00 2001
+From 308795a7713ca6fcd468b60fba9a2fca99cee6a0 Mon Sep 17 00:00:00 2001
From: Nick Terrell <terrelln@fb.com>
Date: Wed, 2 Aug 2017 18:02:13 -0700
-Subject: [PATCH v4 5/5] crypto: Add zstd support
+Subject: [PATCH v5 5/5] crypto: Add zstd support
Adds zstd support to crypto and scompress. Only supports the default
level.
@@ -1662,6 +1662,15 @@ config CRYPTO_LZ4HC
help
This is the LZ4 high compression mode algorithm.
-
+
+config CRYPTO_ZSTD
+ tristate "Zstd compression algorithm"
+ select CRYPTO_ALGAPI
+ This is the zstd algorithm.
+
comment "Random Number Generation"
-
+
config CRYPTO_ANSI_CPRNG
diff --git a/crypto/Makefile b/crypto/Makefile
index d41f033..b22e1e8 100644
obj-$(CONFIG_CRYPTO_USER_API_RNG) += algif_rng.o
obj-$(CONFIG_CRYPTO_USER_API_AEAD) += algif_aead.o
+obj-$(CONFIG_CRYPTO_ZSTD) += zstd.o
-
+
ecdh_generic-y := ecc.o
ecdh_generic-y += ecdh.o
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
+ }
}
};
-
+
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 6ceb0e2..e6b5920 100644
--- a/crypto/testmgr.h
@@ -34631,4 +34631,75 @@ static const struct comp_testvec lz4hc_decomp_tv_template[] = {
},
};
-
+
+static const struct comp_testvec zstd_comp_tv_template[] = {
+ {
+ .inlen = 68,
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Zstd Compression Algorithm");
+MODULE_ALIAS_CRYPTO("zstd");
---
+--
2.9.3
-
-From 0ec6ae4b2c69fcf27785e389391b0add474efd8c Mon Sep 17 00:00:00 2001
+From cc08b43a31fed1289c2027d5090999da569457f1 Mon Sep 17 00:00:00 2001
From: Sean Purcell <me@seanp.xyz>
Date: Thu, 3 Aug 2017 17:47:03 -0700
-Subject: [PATCH v4] squashfs-tools: Add zstd support
+Subject: [PATCH v5] squashfs-tools: Add zstd support
This patch adds zstd support to squashfs-tools. It works with zstd
versions >= 1.0.0. It was originally written by Sean Purcell.
Signed-off-by: Sean Purcell <me@seanp.xyz>
Signed-off-by: Nick Terrell <terrelln@fb.com>
---
+v4 -> v5:
+- Fix patch documentation to reflect that Sean Purcell is the author
+- Don't strip trailing whitespace of unreleated code
+- Make zstd_display_options() static
+
squashfs-tools/Makefile | 21 ++++
squashfs-tools/compressor.c | 8 ++
- squashfs-tools/squashfs_fs.h | 3 +-
+ squashfs-tools/squashfs_fs.h | 1 +
squashfs-tools/zstd_wrapper.c | 254 ++++++++++++++++++++++++++++++++++++++++++
squashfs-tools/zstd_wrapper.h | 48 ++++++++
- 5 files changed, 333 insertions(+), 1 deletion(-)
+ 5 files changed, 332 insertions(+)
create mode 100644 squashfs-tools/zstd_wrapper.c
create mode 100644 squashfs-tools/zstd_wrapper.h
@@ -75,6 +75,19 @@ GZIP_SUPPORT = 1
#LZMA_SUPPORT = 1
#LZMA_DIR = ../../../../LZMA/lzma465
-
+
+
+########### Building ZSTD support ############
+#
@@ -177,6 +190,14 @@ LIBS += -llz4
COMPRESSORS += lz4
endif
-
+
+ifeq ($(ZSTD_SUPPORT),1)
+CFLAGS += -DZSTD_SUPPORT
+MKSQUASHFS_OBJS += zstd_wrapper.o
@@ -65,6 +65,13 @@ static struct compressor xz_comp_ops = {
extern struct compressor xz_comp_ops;
#endif
-
+
+#ifndef ZSTD_SUPPORT
+static struct compressor zstd_comp_ops = {
+ ZSTD_COMPRESSION, "zstd"
+#else
+extern struct compressor zstd_comp_ops;
+#endif
-
+
static struct compressor unknown_comp_ops = {
0, "unknown"
@@ -77,6 +84,7 @@ struct compressor *compressor[] = {
+ &zstd_comp_ops,
&unknown_comp_ops
};
-
+
diff --git a/squashfs-tools/squashfs_fs.h b/squashfs-tools/squashfs_fs.h
-index 791fe12..1f2e8b0 100644
+index 791fe12..afca918 100644
--- a/squashfs-tools/squashfs_fs.h
+++ b/squashfs-tools/squashfs_fs.h
-@@ -24,7 +24,7 @@
- * squashfs_fs.h
- */
-
--#define SQUASHFS_CACHED_FRAGMENTS CONFIG_SQUASHFS_FRAGMENT_CACHE_SIZE
-+#define SQUASHFS_CACHED_FRAGMENTS CONFIG_SQUASHFS_FRAGMENT_CACHE_SIZE
- #define SQUASHFS_MAJOR 4
- #define SQUASHFS_MINOR 0
- #define SQUASHFS_MAGIC 0x73717368
@@ -277,6 +277,7 @@ typedef long long squashfs_inode;
#define LZO_COMPRESSION 3
#define XZ_COMPRESSION 4
#define LZ4_COMPRESSION 5
+#define ZSTD_COMPRESSION 6
-
+
struct squashfs_super_block {
unsigned int s_magic;
diff --git a/squashfs-tools/zstd_wrapper.c b/squashfs-tools/zstd_wrapper.c
new file mode 100644
-index 0000000..0989f0f
+index 0000000..dcab75a
--- /dev/null
+++ b/squashfs-tools/zstd_wrapper.c
@@ -0,0 +1,254 @@
+ return -1;
+}
+
-+void zstd_display_options(void *buffer, int size)
++static void zstd_display_options(void *buffer, int size)
+{
+ struct zstd_comp_opts *comp_opts = buffer;
+
+ int compression_level;
+};
+#endif
---
+--
2.9.3
-
# Linux Kernel Patch
There are four pieces, the `xxhash` kernel module, the `zstd_compress` and `zstd_decompress` kernel modules, the BtrFS patch, and the SquashFS patch.
-The patches are based off of the linux kernel master branch (version 4.10).
+The patches are based off of the linux kernel master branch.
## xxHash kernel module
Benchmarks run on a Ubuntu 14.04 with 2 cores and 4 GiB of RAM.
The VM is running on a Macbook Pro with a 3.1 GHz Intel Core i7 processor,
16 GB of ram, and a SSD.
-The kernel running was built from the master branch with the patch (version 4.10).
+The kernel running was built from the master branch with the patch.
The compression benchmark is copying 10 copies of the
unzipped [silesia corpus](http://mattmahoney.net/dc/silesia.html) into a BtrFS
* The patch is located in `squashfs.diff`
* Additionally `fs/squashfs/zstd_wrapper.c` is provided as a source for convenience.
-* The patch has been tested on a 4.10 kernel.
+* The patch has been tested on the master branch of the kernel.
### Benchmarks
Benchmarks run on a Ubuntu 14.04 with 2 cores and 4 GiB of RAM.
The VM is running on a Macbook Pro with a 3.1 GHz Intel Core i7 processor,
16 GB of ram, and a SSD.
-The kernel running was built from the master branch with the patch (version 4.10).
+The kernel running was built from the master branch with the patch.
The compression benchmark is the file tree from the SquashFS archive found in the
Ubuntu 16.10 desktop image (ubuntu-16.10-desktop-amd64.iso).
struct workspace {
void *mem;
size_t mem_size;
+ size_t window_size;
};
static void *zstd_init(struct squashfs_sb_info *msblk, void *buff)
if (wksp == NULL)
goto failed;
- wksp->mem_size = ZSTD_DStreamWorkspaceBound(max_t(size_t,
- msblk->block_size, SQUASHFS_METADATA_SIZE));
+ wksp->window_size = max_t(size_t,
+ msblk->block_size, SQUASHFS_METADATA_SIZE);
+ wksp->mem_size = ZSTD_DStreamWorkspaceBound(wksp->window_size);
wksp->mem = vmalloc(wksp->mem_size);
if (wksp->mem == NULL)
goto failed;
ZSTD_inBuffer in_buf = { NULL, 0, 0 };
ZSTD_outBuffer out_buf = { NULL, 0, 0 };
- stream = ZSTD_initDStream(wksp->mem_size, wksp->mem, wksp->mem_size);
+ stream = ZSTD_initDStream(wksp->window_size, wksp->mem, wksp->mem_size);
if (!stream) {
ERROR("Failed to initialize zstd decompressor\n");
mlCodeTable[seqStorePtr->longLengthPos] = MaxML;
}
-ZSTD_STATIC size_t ZSTD_compressSequences(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, size_t srcSize)
+ZSTD_STATIC size_t ZSTD_compressSequences_internal(ZSTD_CCtx *zc, void *dst, size_t dstCapacity)
{
const int longOffsets = zc->params.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
const seqStore_t *seqStorePtr = &(zc->seqStore);
else
op[0] = 0xFF, ZSTD_writeLE16(op + 1, (U16)(nbSeq - LONGNBSEQ)), op += 3;
if (nbSeq == 0)
- goto _check_compressibility;
+ return op - ostart;
/* seqHead : flags for FSE encoding type */
seqHead = op++;
op += streamSize;
}
}
+ return op - ostart;
+}
-/* check compressibility */
-_check_compressibility:
- {
- size_t const minGain = ZSTD_minGain(srcSize);
- size_t const maxCSize = srcSize - minGain;
- if ((size_t)(op - ostart) >= maxCSize) {
- zc->flagStaticHufTable = HUF_repeat_none;
- return 0;
- }
- }
+ZSTD_STATIC size_t ZSTD_compressSequences(ZSTD_CCtx *zc, void *dst, size_t dstCapacity, size_t srcSize)
+{
+ size_t const cSize = ZSTD_compressSequences_internal(zc, dst, dstCapacity);
+ size_t const minGain = ZSTD_minGain(srcSize);
+ size_t const maxCSize = srcSize - minGain;
+ /* If the srcSize <= dstCapacity, then there is enough space to write a
+ * raw uncompressed block. Since we ran out of space, the block must not
+ * be compressible, so fall back to a raw uncompressed block.
+ */
+ int const uncompressibleError = cSize == ERROR(dstSize_tooSmall) && srcSize <= dstCapacity;
+ int i;
- /* confirm repcodes */
- {
- int i;
- for (i = 0; i < ZSTD_REP_NUM; i++)
- zc->rep[i] = zc->repToConfirm[i];
+ if (ZSTD_isError(cSize) && !uncompressibleError)
+ return cSize;
+ if (cSize >= maxCSize || uncompressibleError) {
+ zc->flagStaticHufTable = HUF_repeat_none;
+ return 0;
}
-
- return op - ostart;
+ /* confirm repcodes */
+ for (i = 0; i < ZSTD_REP_NUM; i++)
+ zc->rep[i] = zc->repToConfirm[i];
+ return cSize;
}
/*! ZSTD_storeSeq() :
#define WILDCOPY_OVERLENGTH 8
ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
{
- if (length > 0)
- memcpy(dst, src, length);
+ const BYTE* ip = (const BYTE*)src;
+ BYTE* op = (BYTE*)dst;
+ BYTE* const oend = op + length;
+ /* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388.
+ * Avoid the bad case where the loop only runs once by handling the
+ * special case separately. This doesn't trigger the bug because it
+ * doesn't involve pointer/integer overflow.
+ */
+ if (length <= 8)
+ return ZSTD_copy8(dst, src);
+ do {
+ ZSTD_copy8(op, ip);
+ op += 8;
+ ip += 8;
+ } while (op < oend);
}
/*-*******************************************
projects / thirdparty / zstd.git / commitdiff
