diff options
| author | vitalyisaev <[email protected]> | 2023-06-29 10:00:50 +0300 | 
|---|---|---|
| committer | vitalyisaev <[email protected]> | 2023-06-29 10:00:50 +0300 | 
| commit | 6ffe9e53658409f212834330e13564e4952558f6 (patch) | |
| tree | 85b1e00183517648b228aafa7c8fb07f5276f419 /contrib/libs/llvm14/include/llvm/Support/BinaryStreamArray.h | |
| parent | 726057070f9c5a91fc10fde0d5024913d10f1ab9 (diff) | |
YQ Connector: support managed ClickHouse
Со стороны dqrun можно обратиться к инстансу коннектора, который работает на streaming стенде, и извлечь данные из облачного CH.
Diffstat (limited to 'contrib/libs/llvm14/include/llvm/Support/BinaryStreamArray.h')
| -rw-r--r-- | contrib/libs/llvm14/include/llvm/Support/BinaryStreamArray.h | 383 | 
1 files changed, 383 insertions, 0 deletions
| diff --git a/contrib/libs/llvm14/include/llvm/Support/BinaryStreamArray.h b/contrib/libs/llvm14/include/llvm/Support/BinaryStreamArray.h new file mode 100644 index 00000000000..e65f54ba585 --- /dev/null +++ b/contrib/libs/llvm14/include/llvm/Support/BinaryStreamArray.h @@ -0,0 +1,383 @@ +#pragma once + +#ifdef __GNUC__ +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wunused-parameter" +#endif + +//===- BinaryStreamArray.h - Array backed by an arbitrary stream *- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +/// +/// \file +/// Lightweight arrays that are backed by an arbitrary BinaryStream.  This file +/// provides two different array implementations. +/// +///     VarStreamArray - Arrays of variable length records.  The user specifies +///       an Extractor type that can extract a record from a given offset and +///       return the number of bytes consumed by the record. +/// +///     FixedStreamArray - Arrays of fixed length records.  This is similar in +///       spirit to ArrayRef<T>, but since it is backed by a BinaryStream, the +///       elements of the array need not be laid out in contiguous memory. +/// + +#ifndef LLVM_SUPPORT_BINARYSTREAMARRAY_H +#define LLVM_SUPPORT_BINARYSTREAMARRAY_H + +#include "llvm/ADT/ArrayRef.h" +#include "llvm/ADT/iterator.h" +#include "llvm/Support/Alignment.h" +#include "llvm/Support/BinaryStreamRef.h" +#include "llvm/Support/Error.h" +#include <cassert> +#include <cstdint> + +namespace llvm { + +/// VarStreamArrayExtractor is intended to be specialized to provide customized +/// extraction logic.  On input it receives a BinaryStreamRef pointing to the +/// beginning of the next record, but where the length of the record is not yet +/// known.  Upon completion, it should return an appropriate Error instance if +/// a record could not be extracted, or if one could be extracted it should +/// return success and set Len to the number of bytes this record occupied in +/// the underlying stream, and it should fill out the fields of the value type +/// Item appropriately to represent the current record. +/// +/// You can specialize this template for your own custom value types to avoid +/// having to specify a second template argument to VarStreamArray (documented +/// below). +template <typename T> struct VarStreamArrayExtractor { +  // Method intentionally deleted.  You must provide an explicit specialization +  // with the following method implemented. +  Error operator()(BinaryStreamRef Stream, uint32_t &Len, +                   T &Item) const = delete; +}; + +/// VarStreamArray represents an array of variable length records backed by a +/// stream.  This could be a contiguous sequence of bytes in memory, it could +/// be a file on disk, or it could be a PDB stream where bytes are stored as +/// discontiguous blocks in a file.  Usually it is desirable to treat arrays +/// as contiguous blocks of memory, but doing so with large PDB files, for +/// example, could mean allocating huge amounts of memory just to allow +/// re-ordering of stream data to be contiguous before iterating over it.  By +/// abstracting this out, we need not duplicate this memory, and we can +/// iterate over arrays in arbitrarily formatted streams.  Elements are parsed +/// lazily on iteration, so there is no upfront cost associated with building +/// or copying a VarStreamArray, no matter how large it may be. +/// +/// You create a VarStreamArray by specifying a ValueType and an Extractor type. +/// If you do not specify an Extractor type, you are expected to specialize +/// VarStreamArrayExtractor<T> for your ValueType. +/// +/// By default an Extractor is default constructed in the class, but in some +/// cases you might find it useful for an Extractor to maintain state across +/// extractions.  In this case you can provide your own Extractor through a +/// secondary constructor.  The following examples show various ways of +/// creating a VarStreamArray. +/// +///       // Will use VarStreamArrayExtractor<MyType> as the extractor. +///       VarStreamArray<MyType> MyTypeArray; +/// +///       // Will use a default-constructed MyExtractor as the extractor. +///       VarStreamArray<MyType, MyExtractor> MyTypeArray2; +/// +///       // Will use the specific instance of MyExtractor provided. +///       // MyExtractor need not be default-constructible in this case. +///       MyExtractor E(SomeContext); +///       VarStreamArray<MyType, MyExtractor> MyTypeArray3(E); +/// + +template <typename ValueType, typename Extractor> class VarStreamArrayIterator; + +template <typename ValueType, +          typename Extractor = VarStreamArrayExtractor<ValueType>> +class VarStreamArray { +  friend class VarStreamArrayIterator<ValueType, Extractor>; + +public: +  typedef VarStreamArrayIterator<ValueType, Extractor> Iterator; + +  VarStreamArray() = default; + +  explicit VarStreamArray(const Extractor &E) : E(E) {} + +  explicit VarStreamArray(BinaryStreamRef Stream, uint32_t Skew = 0) +      : Stream(Stream), Skew(Skew) {} + +  VarStreamArray(BinaryStreamRef Stream, const Extractor &E, uint32_t Skew = 0) +      : Stream(Stream), E(E), Skew(Skew) {} + +  Iterator begin(bool *HadError = nullptr) const { +    return Iterator(*this, E, Skew, nullptr); +  } + +  bool valid() const { return Stream.valid(); } + +  uint32_t skew() const { return Skew; } +  Iterator end() const { return Iterator(E); } + +  bool empty() const { return Stream.getLength() == 0; } + +  VarStreamArray<ValueType, Extractor> substream(uint32_t Begin, +                                                 uint32_t End) const { +    assert(Begin >= Skew); +    // We should never cut off the beginning of the stream since it might be +    // skewed, meaning the initial bytes are important. +    BinaryStreamRef NewStream = Stream.slice(0, End); +    return {NewStream, E, Begin}; +  } + +  /// given an offset into the array's underlying stream, return an +  /// iterator to the record at that offset.  This is considered unsafe +  /// since the behavior is undefined if \p Offset does not refer to the +  /// beginning of a valid record. +  Iterator at(uint32_t Offset) const { +    return Iterator(*this, E, Offset, nullptr); +  } + +  const Extractor &getExtractor() const { return E; } +  Extractor &getExtractor() { return E; } + +  BinaryStreamRef getUnderlyingStream() const { return Stream; } +  void setUnderlyingStream(BinaryStreamRef NewStream, uint32_t NewSkew = 0) { +    Stream = NewStream; +    Skew = NewSkew; +  } + +  void drop_front() { Skew += begin()->length(); } + +private: +  BinaryStreamRef Stream; +  Extractor E; +  uint32_t Skew = 0; +}; + +template <typename ValueType, typename Extractor> +class VarStreamArrayIterator +    : public iterator_facade_base<VarStreamArrayIterator<ValueType, Extractor>, +                                  std::forward_iterator_tag, const ValueType> { +  typedef VarStreamArrayIterator<ValueType, Extractor> IterType; +  typedef VarStreamArray<ValueType, Extractor> ArrayType; + +public: +  VarStreamArrayIterator(const ArrayType &Array, const Extractor &E, +                         uint32_t Offset, bool *HadError) +      : IterRef(Array.Stream.drop_front(Offset)), Extract(E), +        Array(&Array), AbsOffset(Offset), HadError(HadError) { +    if (IterRef.getLength() == 0) +      moveToEnd(); +    else { +      auto EC = Extract(IterRef, ThisLen, ThisValue); +      if (EC) { +        consumeError(std::move(EC)); +        markError(); +      } +    } +  } + +  VarStreamArrayIterator() = default; +  explicit VarStreamArrayIterator(const Extractor &E) : Extract(E) {} +  ~VarStreamArrayIterator() = default; + +  bool operator==(const IterType &R) const { +    if (Array && R.Array) { +      // Both have a valid array, make sure they're same. +      assert(Array == R.Array); +      return IterRef == R.IterRef; +    } + +    // Both iterators are at the end. +    if (!Array && !R.Array) +      return true; + +    // One is not at the end and one is. +    return false; +  } + +  const ValueType &operator*() const { +    assert(Array && !HasError); +    return ThisValue; +  } + +  IterType &operator+=(unsigned N) { +    for (unsigned I = 0; I < N; ++I) { +      // We are done with the current record, discard it so that we are +      // positioned at the next record. +      AbsOffset += ThisLen; +      IterRef = IterRef.drop_front(ThisLen); +      if (IterRef.getLength() == 0) { +        // There is nothing after the current record, we must make this an end +        // iterator. +        moveToEnd(); +      } else { +        // There is some data after the current record. +        auto EC = Extract(IterRef, ThisLen, ThisValue); +        if (EC) { +          consumeError(std::move(EC)); +          markError(); +        } else if (ThisLen == 0) { +          // An empty record? Make this an end iterator. +          moveToEnd(); +        } +      } +    } +    return *this; +  } + +  uint32_t offset() const { return AbsOffset; } +  uint32_t getRecordLength() const { return ThisLen; } + +private: +  void moveToEnd() { +    Array = nullptr; +    ThisLen = 0; +  } +  void markError() { +    moveToEnd(); +    HasError = true; +    if (HadError != nullptr) +      *HadError = true; +  } + +  ValueType ThisValue; +  BinaryStreamRef IterRef; +  Extractor Extract; +  const ArrayType *Array{nullptr}; +  uint32_t ThisLen{0}; +  uint32_t AbsOffset{0}; +  bool HasError{false}; +  bool *HadError{nullptr}; +}; + +template <typename T> class FixedStreamArrayIterator; + +/// FixedStreamArray is similar to VarStreamArray, except with each record +/// having a fixed-length.  As with VarStreamArray, there is no upfront +/// cost associated with building or copying a FixedStreamArray, as the +/// memory for each element is not read from the backing stream until that +/// element is iterated. +template <typename T> class FixedStreamArray { +  friend class FixedStreamArrayIterator<T>; + +public: +  typedef FixedStreamArrayIterator<T> Iterator; + +  FixedStreamArray() = default; +  explicit FixedStreamArray(BinaryStreamRef Stream) : Stream(Stream) { +    assert(Stream.getLength() % sizeof(T) == 0); +  } + +  bool operator==(const FixedStreamArray<T> &Other) const { +    return Stream == Other.Stream; +  } + +  bool operator!=(const FixedStreamArray<T> &Other) const { +    return !(*this == Other); +  } + +  FixedStreamArray(const FixedStreamArray &) = default; +  FixedStreamArray &operator=(const FixedStreamArray &) = default; + +  const T &operator[](uint32_t Index) const { +    assert(Index < size()); +    uint32_t Off = Index * sizeof(T); +    ArrayRef<uint8_t> Data; +    if (auto EC = Stream.readBytes(Off, sizeof(T), Data)) { +      assert(false && "Unexpected failure reading from stream"); +      // This should never happen since we asserted that the stream length was +      // an exact multiple of the element size. +      consumeError(std::move(EC)); +    } +    assert(isAddrAligned(Align::Of<T>(), Data.data())); +    return *reinterpret_cast<const T *>(Data.data()); +  } + +  uint32_t size() const { return Stream.getLength() / sizeof(T); } + +  bool empty() const { return size() == 0; } + +  FixedStreamArrayIterator<T> begin() const { +    return FixedStreamArrayIterator<T>(*this, 0); +  } + +  FixedStreamArrayIterator<T> end() const { +    return FixedStreamArrayIterator<T>(*this, size()); +  } + +  const T &front() const { return *begin(); } +  const T &back() const { +    FixedStreamArrayIterator<T> I = end(); +    return *(--I); +  } + +  BinaryStreamRef getUnderlyingStream() const { return Stream; } + +private: +  BinaryStreamRef Stream; +}; + +template <typename T> +class FixedStreamArrayIterator +    : public iterator_facade_base<FixedStreamArrayIterator<T>, +                                  std::random_access_iterator_tag, const T> { + +public: +  FixedStreamArrayIterator(const FixedStreamArray<T> &Array, uint32_t Index) +      : Array(Array), Index(Index) {} + +  FixedStreamArrayIterator(const FixedStreamArrayIterator<T> &Other) +      : Array(Other.Array), Index(Other.Index) {} +  FixedStreamArrayIterator<T> & +  operator=(const FixedStreamArrayIterator<T> &Other) { +    Array = Other.Array; +    Index = Other.Index; +    return *this; +  } + +  const T &operator*() const { return Array[Index]; } +  const T &operator*() { return Array[Index]; } + +  bool operator==(const FixedStreamArrayIterator<T> &R) const { +    assert(Array == R.Array); +    return (Index == R.Index) && (Array == R.Array); +  } + +  FixedStreamArrayIterator<T> &operator+=(std::ptrdiff_t N) { +    Index += N; +    return *this; +  } + +  FixedStreamArrayIterator<T> &operator-=(std::ptrdiff_t N) { +    assert(std::ptrdiff_t(Index) >= N); +    Index -= N; +    return *this; +  } + +  std::ptrdiff_t operator-(const FixedStreamArrayIterator<T> &R) const { +    assert(Array == R.Array); +    assert(Index >= R.Index); +    return Index - R.Index; +  } + +  bool operator<(const FixedStreamArrayIterator<T> &RHS) const { +    assert(Array == RHS.Array); +    return Index < RHS.Index; +  } + +private: +  FixedStreamArray<T> Array; +  uint32_t Index; +}; + +} // namespace llvm + +#endif // LLVM_SUPPORT_BINARYSTREAMARRAY_H + +#ifdef __GNUC__ +#pragma GCC diagnostic pop +#endif | 
