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authorqrort <qrort@yandex-team.com>2022-11-30 23:47:12 +0300
committerqrort <qrort@yandex-team.com>2022-11-30 23:47:12 +0300
commit22f8ae0e3f5d68b92aecccdf96c1d841a0334311 (patch)
treebffa27765faf54126ad44bcafa89fadecb7a73d7 /library/cpp/streams/xz
parent332b99e2173f0425444abb759eebcb2fafaa9209 (diff)
downloadydb-22f8ae0e3f5d68b92aecccdf96c1d841a0334311.tar.gz
validate canons without yatest_common
Diffstat (limited to 'library/cpp/streams/xz')
-rw-r--r--library/cpp/streams/xz/README.md9
-rw-r--r--library/cpp/streams/xz/decompress.cpp326
-rw-r--r--library/cpp/streams/xz/decompress.h40
-rw-r--r--library/cpp/streams/xz/ut/decompress_ut.cpp26
4 files changed, 401 insertions, 0 deletions
diff --git a/library/cpp/streams/xz/README.md b/library/cpp/streams/xz/README.md
new file mode 100644
index 0000000000..edb344c0fb
--- /dev/null
+++ b/library/cpp/streams/xz/README.md
@@ -0,0 +1,9 @@
+XZ
+===
+`TXzDecompress` supports file formats:
+1) `.xz` - could be generated with CLI-tool `xz`. This format allows concatenating compressed files as is:
+```
+ echo foo | xz > foobar.xz
+ echo bar | xz >> foobar.xz
+```
+2) `.lzma` - could be generated with CLI-tool `lzma` - it is legacy: https://fossies.org/linux/xz/README
diff --git a/library/cpp/streams/xz/decompress.cpp b/library/cpp/streams/xz/decompress.cpp
new file mode 100644
index 0000000000..361b3cff14
--- /dev/null
+++ b/library/cpp/streams/xz/decompress.cpp
@@ -0,0 +1,326 @@
+#include "decompress.h"
+
+#include <contrib/libs/lzma/liblzma/api/lzma.h>
+
+#include <util/generic/yexception.h>
+#include <util/stream/output.h>
+#include <util/stream/str.h>
+#include <util/stream/zerocopy.h>
+
+// Based on https://fossies.org/linux/xz/doc/examples/02_decompress.c
+
+///////////////////////////////////////////////////////////////////////////////
+//
+/// \file 02_decompress.c
+/// \brief Decompress .xz files to stdout
+///
+/// Usage: ./02_decompress INPUT_FILES... > OUTFILE
+///
+/// Example: ./02_decompress foo.xz bar.xz > foobar
+//
+// Author: Lasse Collin
+//
+// This file has been put into the public domain.
+// You can do whatever you want with this file.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+namespace {
+ class IInput {
+ public:
+ virtual ~IInput() = default;
+ virtual size_t Next(const ui8*& ptr) = 0;
+ };
+
+ class TCopyInput: public IInput {
+ public:
+ TCopyInput(IInputStream* slave)
+ : Slave_(slave)
+ {
+ }
+
+ size_t Next(const ui8*& ptr) override {
+ ptr = Inbuf_;
+ return Slave_->Read(Inbuf_, sizeof(Inbuf_));
+ }
+
+ private:
+ IInputStream* Slave_;
+ ui8 Inbuf_[4096];
+ };
+
+ class TZeroCopy: public IInput {
+ public:
+ TZeroCopy(IZeroCopyInput* slave)
+ : Slave_(slave)
+ {
+ }
+
+ size_t Next(const ui8*& ptr) override {
+ return Slave_->Next(&ptr);
+ }
+
+ private:
+ IZeroCopyInput* Slave_;
+ };
+
+ std::unique_ptr<IInput> createInput(IInputStream* slave) {
+ return std::make_unique<TCopyInput>(slave);
+ }
+
+ std::unique_ptr<IInput> createInput(IZeroCopyInput* slave) {
+ return std::make_unique<TZeroCopy>(slave);
+ }
+}
+
+class TUnbufferedXzDecompress::TImpl {
+public:
+ template <class T>
+ TImpl(T* slave)
+ : Input_(createInput(slave))
+ , Strm_(LZMA_STREAM_INIT)
+ {
+ TString err;
+ Y_ENSURE(initDecoder(&Strm_, err),
+ "Error initializing the decoder: " << err);
+ Strm_.next_in = NULL;
+ Strm_.avail_in = 0;
+ }
+
+ ~TImpl() {
+ // Free the memory allocated for the decoder
+ lzma_end(&Strm_);
+ }
+
+ size_t DoRead(void* buf, size_t len) {
+ if (IsOutFinished_) {
+ return 0;
+ }
+
+ size_t res;
+ TString err;
+
+ Y_ENSURE(decompress(buf, len, res, err),
+ "lzma decoder error: " << err);
+
+ return res;
+ }
+
+private:
+ bool decompress(void* buf, size_t len, size_t& outLen, TString& err) {
+ // When LZMA_CONCATENATED flag was used when initializing the decoder,
+ // we need to tell lzma_code() when there will be no more input.
+ // This is done by setting action to LZMA_FINISH instead of LZMA_RUN
+ // in the same way as it is done when encoding.
+ //
+ // When LZMA_CONCATENATED isn't used, there is no need to use
+ // LZMA_FINISH to tell when all the input has been read, but it
+ // is still OK to use it if you want. When LZMA_CONCATENATED isn't
+ // used, the decoder will stop after the first .xz stream. In that
+ // case some unused data may be left in strm->next_in.
+ lzma_action action = LZMA_RUN;
+
+ Strm_.next_out = (ui8*)buf;
+ Strm_.avail_out = len;
+
+ while (true) {
+ if (Strm_.avail_in == 0 && !IsInFinished_) {
+ size_t size = Input_->Next(Strm_.next_in);
+
+ if (size == 0) {
+ IsInFinished_ = true;
+ } else {
+ Strm_.avail_in = size;
+ }
+
+ // Once the end of the input file has been reached,
+ // we need to tell lzma_code() that no more input
+ // will be coming. As said before, this isn't required
+ // if the LZMA_CONCATENATED flag isn't used when
+ // initializing the decoder.
+ if (IsInFinished_)
+ action = LZMA_FINISH;
+ }
+
+ lzma_ret ret = lzma_code(&Strm_, action);
+
+ if (ret == LZMA_STREAM_END) {
+ // Once everything has been decoded successfully, the
+ // return value of lzma_code() will be LZMA_STREAM_END.
+ //
+ // It is important to check for LZMA_STREAM_END. Do not
+ // assume that getting ret != LZMA_OK would mean that
+ // everything has gone well or that when you aren't
+ // getting more output it must have successfully
+ // decoded everything.
+ IsOutFinished_ = true;
+ }
+
+ if (Strm_.avail_out == 0 || ret == LZMA_STREAM_END) {
+ outLen = len - Strm_.avail_out;
+ return true;
+ }
+
+ if (ret != LZMA_OK) {
+ // It's not LZMA_OK nor LZMA_STREAM_END,
+ // so it must be an error code. See lzma/base.h
+ // (src/liblzma/api/lzma/base.h in the source package
+ // or e.g. /usr/include/lzma/base.h depending on the
+ // install prefix) for the list and documentation of
+ // possible values. Many values listen in lzma_ret
+ // enumeration aren't possible in this example, but
+ // can be made possible by enabling memory usage limit
+ // or adding flags to the decoder initialization.
+ switch (ret) {
+ case LZMA_MEM_ERROR:
+ err = "Memory allocation failed";
+ break;
+
+ case LZMA_FORMAT_ERROR:
+ // .xz magic bytes weren't found.
+ err = "The input is not in the .xz format";
+ break;
+
+ case LZMA_OPTIONS_ERROR:
+ // For example, the headers specify a filter
+ // that isn't supported by this liblzma
+ // version (or it hasn't been enabled when
+ // building liblzma, but no-one sane does
+ // that unless building liblzma for an
+ // embedded system). Upgrading to a newer
+ // liblzma might help.
+ //
+ // Note that it is unlikely that the file has
+ // accidentally became corrupt if you get this
+ // error. The integrity of the .xz headers is
+ // always verified with a CRC32, so
+ // unintentionally corrupt files can be
+ // distinguished from unsupported files.
+ err = "Unsupported compression options";
+ break;
+
+ case LZMA_DATA_ERROR:
+ err = "Compressed file is corrupt";
+ break;
+
+ case LZMA_BUF_ERROR:
+ // Typically this error means that a valid
+ // file has got truncated, but it might also
+ // be a damaged part in the file that makes
+ // the decoder think the file is truncated.
+ // If you prefer, you can use the same error
+ // message for this as for LZMA_DATA_ERROR.
+ err = "Compressed file is truncated or "
+ "otherwise corrupt";
+ break;
+
+ default:
+ // This is most likely LZMA_PROG_ERROR.
+ err = "Unknown error, possibly a bug";
+ break;
+ }
+
+ TStringOutput out(err);
+ out << "[" << (int)ret << "]";
+ return false;
+ }
+ }
+ }
+
+ static bool initDecoder(lzma_stream* strm, TString& err) {
+ // Initialize a .xz decoder. The decoder supports a memory usage limit
+ // and a set of flags.
+ //
+ // The memory usage of the decompressor depends on the settings used
+ // to compress a .xz file. It can vary from less than a megabyte to
+ // a few gigabytes, but in practice (at least for now) it rarely
+ // exceeds 65 MiB because that's how much memory is required to
+ // decompress files created with "xz -9". Settings requiring more
+ // memory take extra effort to use and don't (at least for now)
+ // provide significantly better compression in most cases.
+ //
+ // Memory usage limit is useful if it is important that the
+ // decompressor won't consume gigabytes of memory. The need
+ // for limiting depends on the application. In this example,
+ // no memory usage limiting is used. This is done by setting
+ // the limit to UINT64_MAX.
+ //
+ // The .xz format allows concatenating compressed files as is:
+ //
+ // echo foo | xz > foobar.xz
+ // echo bar | xz >> foobar.xz
+ //
+ // When decompressing normal standalone .xz files, LZMA_CONCATENATED
+ // should always be used to support decompression of concatenated
+ // .xz files. If LZMA_CONCATENATED isn't used, the decoder will stop
+ // after the first .xz stream. This can be useful when .xz data has
+ // been embedded inside another file format.
+ //
+ // Flags other than LZMA_CONCATENATED are supported too, and can
+ // be combined with bitwise-or. See lzma/container.h
+ // (src/liblzma/api/lzma/container.h in the source package or e.g.
+ // /usr/include/lzma/container.h depending on the install prefix)
+ // for details.
+ lzma_ret ret = lzma_auto_decoder(
+ strm, UINT64_MAX, LZMA_CONCATENATED);
+
+ // Return successfully if the initialization went fine.
+ if (ret == LZMA_OK)
+ return true;
+
+ // Something went wrong. The possible errors are documented in
+ // lzma/container.h (src/liblzma/api/lzma/container.h in the source
+ // package or e.g. /usr/include/lzma/container.h depending on the
+ // install prefix).
+ //
+ // Note that LZMA_MEMLIMIT_ERROR is never possible here. If you
+ // specify a very tiny limit, the error will be delayed until
+ // the first headers have been parsed by a call to lzma_code().
+ switch (ret) {
+ case LZMA_MEM_ERROR:
+ err = "Memory allocation failed";
+ break;
+
+ case LZMA_OPTIONS_ERROR:
+ err = "Unsupported decompressor flags";
+ break;
+
+ default:
+ // This is most likely LZMA_PROG_ERROR indicating a bug in
+ // this program or in liblzma. It is inconvenient to have a
+ // separate error message for errors that should be impossible
+ // to occur, but knowing the error code is important for
+ // debugging. That's why it is good to print the error code
+ // at least when there is no good error message to show.
+ err = "Unknown error, possibly a bug";
+ break;
+ }
+
+ TStringOutput out(err);
+ out << "[" << (int)ret << "]";
+ return false;
+ }
+
+private:
+ std::unique_ptr<IInput> Input_;
+ lzma_stream Strm_;
+
+ bool IsInFinished_ = false;
+ bool IsOutFinished_ = false;
+};
+
+TUnbufferedXzDecompress::TUnbufferedXzDecompress(IInputStream* slave)
+ : Impl_(std::make_unique<TImpl>(slave))
+{
+}
+
+TUnbufferedXzDecompress::TUnbufferedXzDecompress(IZeroCopyInput* slave)
+ : Impl_(std::make_unique<TImpl>(slave))
+{
+}
+
+TUnbufferedXzDecompress::~TUnbufferedXzDecompress() = default;
+
+size_t TUnbufferedXzDecompress::DoRead(void* buf, size_t len) {
+ return Impl_->DoRead(buf, len);
+}
diff --git a/library/cpp/streams/xz/decompress.h b/library/cpp/streams/xz/decompress.h
new file mode 100644
index 0000000000..8389cbdaf9
--- /dev/null
+++ b/library/cpp/streams/xz/decompress.h
@@ -0,0 +1,40 @@
+#pragma once
+
+#include <util/stream/buffered.h>
+#include <util/stream/input.h>
+
+class IZeroCopyInput;
+
+/**
+ * Unbuffered decompressing stream for .XZ and .LZMA files.
+ *
+ * Do not use it for reading in small pieces.
+ */
+class TUnbufferedXzDecompress: public IInputStream {
+public:
+ TUnbufferedXzDecompress(IInputStream* slave);
+ TUnbufferedXzDecompress(IZeroCopyInput* slave);
+ ~TUnbufferedXzDecompress() override;
+
+private:
+ size_t DoRead(void* buf, size_t len) override;
+
+private:
+ class TImpl;
+ std::unique_ptr<TImpl> Impl_;
+};
+
+/**
+ * Buffered decompressing stream for .XZ and .LZMA files.
+ *
+ * Supports efficient `ReadLine` calls and similar "reading in small pieces"
+ * usage patterns.
+ */
+class TXzDecompress: public TBuffered<TUnbufferedXzDecompress> {
+public:
+ template <class T>
+ inline TXzDecompress(T&& t, size_t buf = 1 << 13)
+ : TBuffered<TUnbufferedXzDecompress>(buf, std::forward<T>(t))
+ {
+ }
+};
diff --git a/library/cpp/streams/xz/ut/decompress_ut.cpp b/library/cpp/streams/xz/ut/decompress_ut.cpp
new file mode 100644
index 0000000000..2ebeca4e85
--- /dev/null
+++ b/library/cpp/streams/xz/ut/decompress_ut.cpp
@@ -0,0 +1,26 @@
+#include <library/cpp/streams/xz/decompress.h>
+
+#include <library/cpp/string_utils/base64/base64.h>
+#include <library/cpp/testing/unittest/registar.h>
+
+Y_UNIT_TEST_SUITE(XzDecompress) {
+ Y_UNIT_TEST(decompress) {
+ TStringStream in;
+ in << Base64Decode("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");
+
+ TXzDecompress xz(&in);
+
+ UNIT_ASSERT_VALUES_EQUAL(
+ xz.ReadAll(),
+ "2020-08-27T18:22:02.332 INFO: Starting blackbox module\n"
+ "2020-08-27T18:22:02.850 INFO: Init libauth (root kspace=<yandex_ru>, sign with key #49)\n"
+ "2020-08-27T18:22:02.851 DEBUG: KeyRing: randoms: table name loaded. Took 0.000918s\n"
+ "2020-08-27T18:22:02.853 DEBUG: KeyRing: randoms: min-max key id loaded. Took 0.001249s\n"
+ "2020-08-27T18:22:02.863 DEBUG: KeyRing: randoms: new keys loaded. Took 0.010837s\n"
+ "2020-08-27T18:22:02.865 DEBUG: Loaded 2389 new key(s) for keyspace 'yandex_ru'. Key ids: 330589-335364\n"
+ "2020-08-27T18:22:02.866 INFO: Attempt to load second time for spacename yandex_ru\n"
+ "2020-08-27T18:22:02.867 DEBUG: KeyRing: randoms_ua: table name loaded. Took 0.000926s\n"
+ "2020-08-27T18:22:02.868 DEBUG: KeyRing: randoms_ua: min-max key id loaded. Took 0.001212s\n"
+ "2020-08-27T18:22:02.871 DEBUG: KeyRing: randoms_ua: new keys loaded. Took 0.003202s\n");
+ }
+}