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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:45:59 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:45:59 +0000
commit19fcec84d8d7d21e796c7624e521b60d28ee21ed (patch)
tree42d26aa27d1e3f7c0b8bd3fd14e7d7082f5008dc /src/zstd/contrib/seekable_format/zstdseek_decompress.c
parentInitial commit. (diff)
downloadceph-upstream/16.2.11+ds.tar.xz
ceph-upstream/16.2.11+ds.zip
Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/zstd/contrib/seekable_format/zstdseek_decompress.c')
-rw-r--r--src/zstd/contrib/seekable_format/zstdseek_decompress.c467
1 files changed, 467 insertions, 0 deletions
diff --git a/src/zstd/contrib/seekable_format/zstdseek_decompress.c b/src/zstd/contrib/seekable_format/zstdseek_decompress.c
new file mode 100644
index 000000000..abfd1e902
--- /dev/null
+++ b/src/zstd/contrib/seekable_format/zstdseek_decompress.c
@@ -0,0 +1,467 @@
+/*
+ * Copyright (c) 2017-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+/* *********************************************************
+* Turn on Large Files support (>4GB) for 32-bit Linux/Unix
+***********************************************************/
+#if !defined(__64BIT__) || defined(__MINGW32__) /* No point defining Large file for 64 bit but MinGW-w64 requires it */
+# if !defined(_FILE_OFFSET_BITS)
+# define _FILE_OFFSET_BITS 64 /* turn off_t into a 64-bit type for ftello, fseeko */
+# endif
+# if !defined(_LARGEFILE_SOURCE) /* obsolete macro, replaced with _FILE_OFFSET_BITS */
+# define _LARGEFILE_SOURCE 1 /* Large File Support extension (LFS) - fseeko, ftello */
+# endif
+# if defined(_AIX) || defined(__hpux)
+# define _LARGE_FILES /* Large file support on 32-bits AIX and HP-UX */
+# endif
+#endif
+
+/* ************************************************************
+* Avoid fseek()'s 2GiB barrier with MSVC, macOS, *BSD, MinGW
+***************************************************************/
+#if defined(_MSC_VER) && _MSC_VER >= 1400
+# define LONG_SEEK _fseeki64
+#elif !defined(__64BIT__) && (PLATFORM_POSIX_VERSION >= 200112L) /* No point defining Large file for 64 bit */
+# define LONG_SEEK fseeko
+#elif defined(__MINGW32__) && !defined(__STRICT_ANSI__) && !defined(__NO_MINGW_LFS) && defined(__MSVCRT__)
+# define LONG_SEEK fseeko64
+#elif defined(_WIN32) && !defined(__DJGPP__)
+# include <windows.h>
+ static int LONG_SEEK(FILE* file, __int64 offset, int origin) {
+ LARGE_INTEGER off;
+ DWORD method;
+ off.QuadPart = offset;
+ if (origin == SEEK_END)
+ method = FILE_END;
+ else if (origin == SEEK_CUR)
+ method = FILE_CURRENT;
+ else
+ method = FILE_BEGIN;
+
+ if (SetFilePointerEx((HANDLE) _get_osfhandle(_fileno(file)), off, NULL, method))
+ return 0;
+ else
+ return -1;
+ }
+#else
+# define LONG_SEEK fseek
+#endif
+
+#include <stdlib.h> /* malloc, free */
+#include <stdio.h> /* FILE* */
+#include <limits.h> /* UNIT_MAX */
+#include <assert.h>
+
+#define XXH_STATIC_LINKING_ONLY
+#define XXH_NAMESPACE ZSTD_
+#include "xxhash.h"
+
+#define ZSTD_STATIC_LINKING_ONLY
+#include "zstd.h"
+#include "zstd_errors.h"
+#include "mem.h"
+#include "zstd_seekable.h"
+
+#undef ERROR
+#define ERROR(name) ((size_t)-ZSTD_error_##name)
+
+#define CHECK_IO(f) { int const errcod = (f); if (errcod < 0) return ERROR(seekableIO); }
+
+#undef MIN
+#undef MAX
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+
+/* Special-case callbacks for FILE* and in-memory modes, so that we can treat
+ * them the same way as the advanced API */
+static int ZSTD_seekable_read_FILE(void* opaque, void* buffer, size_t n)
+{
+ size_t const result = fread(buffer, 1, n, (FILE*)opaque);
+ if (result != n) {
+ return -1;
+ }
+ return 0;
+}
+
+static int ZSTD_seekable_seek_FILE(void* opaque, long long offset, int origin)
+{
+ int const ret = LONG_SEEK((FILE*)opaque, offset, origin);
+ if (ret) return ret;
+ return fflush((FILE*)opaque);
+}
+
+typedef struct {
+ const void *ptr;
+ size_t size;
+ size_t pos;
+} buffWrapper_t;
+
+static int ZSTD_seekable_read_buff(void* opaque, void* buffer, size_t n)
+{
+ buffWrapper_t* buff = (buffWrapper_t*) opaque;
+ if (buff->pos + n > buff->size) return -1;
+ memcpy(buffer, (const BYTE*)buff->ptr + buff->pos, n);
+ buff->pos += n;
+ return 0;
+}
+
+static int ZSTD_seekable_seek_buff(void* opaque, long long offset, int origin)
+{
+ buffWrapper_t* const buff = (buffWrapper_t*) opaque;
+ unsigned long long newOffset;
+ switch (origin) {
+ case SEEK_SET:
+ newOffset = offset;
+ break;
+ case SEEK_CUR:
+ newOffset = (unsigned long long)buff->pos + offset;
+ break;
+ case SEEK_END:
+ newOffset = (unsigned long long)buff->size + offset;
+ break;
+ default:
+ assert(0); /* not possible */
+ }
+ if (newOffset > buff->size) {
+ return -1;
+ }
+ buff->pos = newOffset;
+ return 0;
+}
+
+typedef struct {
+ U64 cOffset;
+ U64 dOffset;
+ U32 checksum;
+} seekEntry_t;
+
+typedef struct {
+ seekEntry_t* entries;
+ size_t tableLen;
+
+ int checksumFlag;
+} seekTable_t;
+
+#define SEEKABLE_BUFF_SIZE ZSTD_BLOCKSIZE_MAX
+
+struct ZSTD_seekable_s {
+ ZSTD_DStream* dstream;
+ seekTable_t seekTable;
+ ZSTD_seekable_customFile src;
+
+ U64 decompressedOffset;
+ U32 curFrame;
+
+ BYTE inBuff[SEEKABLE_BUFF_SIZE]; /* need to do our own input buffering */
+ BYTE outBuff[SEEKABLE_BUFF_SIZE]; /* so we can efficiently decompress the
+ starts of chunks before we get to the
+ desired section */
+ ZSTD_inBuffer in; /* maintain continuity across ZSTD_seekable_decompress operations */
+ buffWrapper_t buffWrapper; /* for `src.opaque` in in-memory mode */
+
+ XXH64_state_t xxhState;
+};
+
+ZSTD_seekable* ZSTD_seekable_create(void)
+{
+ ZSTD_seekable* zs = malloc(sizeof(ZSTD_seekable));
+
+ if (zs == NULL) return NULL;
+
+ /* also initializes stage to zsds_init */
+ memset(zs, 0, sizeof(*zs));
+
+ zs->dstream = ZSTD_createDStream();
+ if (zs->dstream == NULL) {
+ free(zs);
+ return NULL;
+ }
+
+ return zs;
+}
+
+size_t ZSTD_seekable_free(ZSTD_seekable* zs)
+{
+ if (zs == NULL) return 0; /* support free on null */
+ ZSTD_freeDStream(zs->dstream);
+ free(zs->seekTable.entries);
+ free(zs);
+
+ return 0;
+}
+
+/** ZSTD_seekable_offsetToFrameIndex() :
+ * Performs a binary search to find the last frame with a decompressed offset
+ * <= pos
+ * @return : the frame's index */
+unsigned ZSTD_seekable_offsetToFrameIndex(ZSTD_seekable* const zs, unsigned long long pos)
+{
+ U32 lo = 0;
+ U32 hi = (U32)zs->seekTable.tableLen;
+ assert(zs->seekTable.tableLen <= UINT_MAX);
+
+ if (pos >= zs->seekTable.entries[zs->seekTable.tableLen].dOffset) {
+ return (U32)zs->seekTable.tableLen;
+ }
+
+ while (lo + 1 < hi) {
+ U32 const mid = lo + ((hi - lo) >> 1);
+ if (zs->seekTable.entries[mid].dOffset <= pos) {
+ lo = mid;
+ } else {
+ hi = mid;
+ }
+ }
+ return lo;
+}
+
+unsigned ZSTD_seekable_getNumFrames(ZSTD_seekable* const zs)
+{
+ assert(zs->seekTable.tableLen <= UINT_MAX);
+ return (unsigned)zs->seekTable.tableLen;
+}
+
+unsigned long long ZSTD_seekable_getFrameCompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex)
+{
+ if (frameIndex >= zs->seekTable.tableLen) return ZSTD_SEEKABLE_FRAMEINDEX_TOOLARGE;
+ return zs->seekTable.entries[frameIndex].cOffset;
+}
+
+unsigned long long ZSTD_seekable_getFrameDecompressedOffset(ZSTD_seekable* const zs, unsigned frameIndex)
+{
+ if (frameIndex >= zs->seekTable.tableLen) return ZSTD_SEEKABLE_FRAMEINDEX_TOOLARGE;
+ return zs->seekTable.entries[frameIndex].dOffset;
+}
+
+size_t ZSTD_seekable_getFrameCompressedSize(ZSTD_seekable* const zs, unsigned frameIndex)
+{
+ if (frameIndex >= zs->seekTable.tableLen) return ERROR(frameIndex_tooLarge);
+ return zs->seekTable.entries[frameIndex + 1].cOffset -
+ zs->seekTable.entries[frameIndex].cOffset;
+}
+
+size_t ZSTD_seekable_getFrameDecompressedSize(ZSTD_seekable* const zs, unsigned frameIndex)
+{
+ if (frameIndex > zs->seekTable.tableLen) return ERROR(frameIndex_tooLarge);
+ return zs->seekTable.entries[frameIndex + 1].dOffset -
+ zs->seekTable.entries[frameIndex].dOffset;
+}
+
+static size_t ZSTD_seekable_loadSeekTable(ZSTD_seekable* zs)
+{
+ int checksumFlag;
+ ZSTD_seekable_customFile src = zs->src;
+ /* read the footer, fixed size */
+ CHECK_IO(src.seek(src.opaque, -(int)ZSTD_seekTableFooterSize, SEEK_END));
+ CHECK_IO(src.read(src.opaque, zs->inBuff, ZSTD_seekTableFooterSize));
+
+ if (MEM_readLE32(zs->inBuff + 5) != ZSTD_SEEKABLE_MAGICNUMBER) {
+ return ERROR(prefix_unknown);
+ }
+
+ { BYTE const sfd = zs->inBuff[4];
+ checksumFlag = sfd >> 7;
+
+ /* check reserved bits */
+ if ((checksumFlag >> 2) & 0x1f) {
+ return ERROR(corruption_detected);
+ }
+ }
+
+ { U32 const numFrames = MEM_readLE32(zs->inBuff);
+ U32 const sizePerEntry = 8 + (checksumFlag?4:0);
+ U32 const tableSize = sizePerEntry * numFrames;
+ U32 const frameSize = tableSize + ZSTD_seekTableFooterSize + ZSTD_SKIPPABLEHEADERSIZE;
+
+ U32 remaining = frameSize - ZSTD_seekTableFooterSize; /* don't need to re-read footer */
+ {
+ U32 const toRead = MIN(remaining, SEEKABLE_BUFF_SIZE);
+
+ CHECK_IO(src.seek(src.opaque, -(S64)frameSize, SEEK_END));
+ CHECK_IO(src.read(src.opaque, zs->inBuff, toRead));
+
+ remaining -= toRead;
+ }
+
+ if (MEM_readLE32(zs->inBuff) != (ZSTD_MAGIC_SKIPPABLE_START | 0xE)) {
+ return ERROR(prefix_unknown);
+ }
+ if (MEM_readLE32(zs->inBuff+4) + ZSTD_SKIPPABLEHEADERSIZE != frameSize) {
+ return ERROR(prefix_unknown);
+ }
+
+ { /* Allocate an extra entry at the end so that we can do size
+ * computations on the last element without special case */
+ seekEntry_t* entries = (seekEntry_t*)malloc(sizeof(seekEntry_t) * (numFrames + 1));
+
+ U32 idx = 0;
+ U32 pos = 8;
+
+
+ U64 cOffset = 0;
+ U64 dOffset = 0;
+
+ if (!entries) {
+ free(entries);
+ return ERROR(memory_allocation);
+ }
+
+ /* compute cumulative positions */
+ for (; idx < numFrames; idx++) {
+ if (pos + sizePerEntry > SEEKABLE_BUFF_SIZE) {
+ U32 const offset = SEEKABLE_BUFF_SIZE - pos;
+ U32 const toRead = MIN(remaining, SEEKABLE_BUFF_SIZE - offset);
+ memmove(zs->inBuff, zs->inBuff + pos, offset); /* move any data we haven't read yet */
+ CHECK_IO(src.read(src.opaque, zs->inBuff+offset, toRead));
+ remaining -= toRead;
+ pos = 0;
+ }
+ entries[idx].cOffset = cOffset;
+ entries[idx].dOffset = dOffset;
+
+ cOffset += MEM_readLE32(zs->inBuff + pos);
+ pos += 4;
+ dOffset += MEM_readLE32(zs->inBuff + pos);
+ pos += 4;
+ if (checksumFlag) {
+ entries[idx].checksum = MEM_readLE32(zs->inBuff + pos);
+ pos += 4;
+ }
+ }
+ entries[numFrames].cOffset = cOffset;
+ entries[numFrames].dOffset = dOffset;
+
+ zs->seekTable.entries = entries;
+ zs->seekTable.tableLen = numFrames;
+ zs->seekTable.checksumFlag = checksumFlag;
+ return 0;
+ }
+ }
+}
+
+size_t ZSTD_seekable_initBuff(ZSTD_seekable* zs, const void* src, size_t srcSize)
+{
+ zs->buffWrapper = (buffWrapper_t){src, srcSize, 0};
+ { ZSTD_seekable_customFile srcFile = {&zs->buffWrapper,
+ &ZSTD_seekable_read_buff,
+ &ZSTD_seekable_seek_buff};
+ return ZSTD_seekable_initAdvanced(zs, srcFile); }
+}
+
+size_t ZSTD_seekable_initFile(ZSTD_seekable* zs, FILE* src)
+{
+ ZSTD_seekable_customFile srcFile = {src, &ZSTD_seekable_read_FILE,
+ &ZSTD_seekable_seek_FILE};
+ return ZSTD_seekable_initAdvanced(zs, srcFile);
+}
+
+size_t ZSTD_seekable_initAdvanced(ZSTD_seekable* zs, ZSTD_seekable_customFile src)
+{
+ zs->src = src;
+
+ { const size_t seekTableInit = ZSTD_seekable_loadSeekTable(zs);
+ if (ZSTD_isError(seekTableInit)) return seekTableInit; }
+
+ zs->decompressedOffset = (U64)-1;
+ zs->curFrame = (U32)-1;
+
+ { const size_t dstreamInit = ZSTD_initDStream(zs->dstream);
+ if (ZSTD_isError(dstreamInit)) return dstreamInit; }
+ return 0;
+}
+
+size_t ZSTD_seekable_decompress(ZSTD_seekable* zs, void* dst, size_t len, unsigned long long offset)
+{
+ U32 targetFrame = ZSTD_seekable_offsetToFrameIndex(zs, offset);
+ do {
+ /* check if we can continue from a previous decompress job */
+ if (targetFrame != zs->curFrame || offset != zs->decompressedOffset) {
+ zs->decompressedOffset = zs->seekTable.entries[targetFrame].dOffset;
+ zs->curFrame = targetFrame;
+
+ CHECK_IO(zs->src.seek(zs->src.opaque,
+ zs->seekTable.entries[targetFrame].cOffset,
+ SEEK_SET));
+ zs->in = (ZSTD_inBuffer){zs->inBuff, 0, 0};
+ XXH64_reset(&zs->xxhState, 0);
+ ZSTD_resetDStream(zs->dstream);
+ }
+
+ while (zs->decompressedOffset < offset + len) {
+ size_t toRead;
+ ZSTD_outBuffer outTmp;
+ size_t prevOutPos;
+ if (zs->decompressedOffset < offset) {
+ /* dummy decompressions until we get to the target offset */
+ outTmp = (ZSTD_outBuffer){zs->outBuff, MIN(SEEKABLE_BUFF_SIZE, offset - zs->decompressedOffset), 0};
+ } else {
+ outTmp = (ZSTD_outBuffer){dst, len, zs->decompressedOffset - offset};
+ }
+
+ prevOutPos = outTmp.pos;
+ toRead = ZSTD_decompressStream(zs->dstream, &outTmp, &zs->in);
+ if (ZSTD_isError(toRead)) {
+ return toRead;
+ }
+
+ if (zs->seekTable.checksumFlag) {
+ XXH64_update(&zs->xxhState, (BYTE*)outTmp.dst + prevOutPos,
+ outTmp.pos - prevOutPos);
+ }
+ zs->decompressedOffset += outTmp.pos - prevOutPos;
+
+ if (toRead == 0) {
+ /* frame complete */
+
+ /* verify checksum */
+ if (zs->seekTable.checksumFlag &&
+ (XXH64_digest(&zs->xxhState) & 0xFFFFFFFFU) !=
+ zs->seekTable.entries[targetFrame].checksum) {
+ return ERROR(corruption_detected);
+ }
+
+ if (zs->decompressedOffset < offset + len) {
+ /* go back to the start and force a reset of the stream */
+ targetFrame = ZSTD_seekable_offsetToFrameIndex(zs, zs->decompressedOffset);
+ }
+ break;
+ }
+
+ /* read in more data if we're done with this buffer */
+ if (zs->in.pos == zs->in.size) {
+ toRead = MIN(toRead, SEEKABLE_BUFF_SIZE);
+ CHECK_IO(zs->src.read(zs->src.opaque, zs->inBuff, toRead));
+ zs->in.size = toRead;
+ zs->in.pos = 0;
+ }
+ }
+ } while (zs->decompressedOffset != offset + len);
+
+ return len;
+}
+
+size_t ZSTD_seekable_decompressFrame(ZSTD_seekable* zs, void* dst, size_t dstSize, unsigned frameIndex)
+{
+ if (frameIndex >= zs->seekTable.tableLen) {
+ return ERROR(frameIndex_tooLarge);
+ }
+
+ {
+ size_t const decompressedSize =
+ zs->seekTable.entries[frameIndex + 1].dOffset -
+ zs->seekTable.entries[frameIndex].dOffset;
+ if (dstSize < decompressedSize) {
+ return ERROR(dstSize_tooSmall);
+ }
+ return ZSTD_seekable_decompress(
+ zs, dst, decompressedSize,
+ zs->seekTable.entries[frameIndex].dOffset);
+ }
+}