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author | max42 <max42@yandex-team.com> | 2023-07-29 00:02:16 +0300 |
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committer | max42 <max42@yandex-team.com> | 2023-07-29 00:02:16 +0300 |
commit | 73b89de71748a21e102d27b9f3ed1bf658766cb5 (patch) | |
tree | 188bbd2d622fa91cdcbb1b6d6d77fbc84a0646f5 /library/cpp/yt/string/raw_formatter.h | |
parent | 528e321bcc2a2b67b53aeba58c3bd88305a141ee (diff) | |
download | ydb-73b89de71748a21e102d27b9f3ed1bf658766cb5.tar.gz |
YT-19210: expose YQL shared library for YT.
After this, a new target libyqlplugin.so appears. in open-source cmake build.
Diff in open-source YDB repo looks like the following: https://paste.yandex-team.ru/f302bdb4-7ef2-4362-91c7-6ca45f329264
Diffstat (limited to 'library/cpp/yt/string/raw_formatter.h')
-rw-r--r-- | library/cpp/yt/string/raw_formatter.h | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/library/cpp/yt/string/raw_formatter.h b/library/cpp/yt/string/raw_formatter.h new file mode 100644 index 0000000000..6956330883 --- /dev/null +++ b/library/cpp/yt/string/raw_formatter.h @@ -0,0 +1,212 @@ +#pragma once + +#include "guid.h" + +#include <algorithm> +#include <array> + +#include <util/generic/strbuf.h> + +namespace NYT { + +//////////////////////////////////////////////////////////////////////////////// + +//! A dead-simple string formatter. +/*! + * This formatter is intended to be as simple as possible and async signal safe. + * This is the reason we do not use printf(): it does not meet signal-safety + * requirements. + */ + +class TBaseFormatter +{ +public: + TBaseFormatter(char* buffer, int length) + : Begin_(buffer) + , Cursor_(buffer) + , End_(buffer + length) + { } + + //! Returns an underlying cursor. + char* GetCursor() + { + return Cursor_; + } + + //! Returns an pointer to the underlying buffer. + const char* GetData() const + { + return Begin_; + } + + //! Returns the number of bytes written in the buffer. + int GetBytesWritten() const + { + return Cursor_ - Begin_; + } + + //! Returns the number of bytes available in the buffer. + int GetBytesRemaining() const + { + return End_ - Cursor_; + } + + //! Advances the internal cursor #count symbols forward (assuming the data is already present). + void Advance(int count) + { + Cursor_ += count; + + if (Cursor_ > End_) { + Cursor_ = End_; + } + } + + //! Drops trailing #count symbols (assuming these are present). + void Revert(int count) + { + Cursor_ -= count; + } + + //! Appends the string and updates the internal cursor. + void AppendString(const char* string) + { + while (*string != '\0' && Cursor_ < End_) { + *Cursor_++ = *string++; + } + } + + //! Appends the string and updates the internal cursor. + void AppendString(TStringBuf string) + { + size_t position = 0; + while (position < string.length() && Cursor_ < End_) { + *Cursor_++ = string[position++]; + } + } + + //! Appends a single character and updates the internal cursor. + void AppendChar(char ch) + { + if (Cursor_ < End_) { + *Cursor_++ = ch; + } + } + + //! Formats |number| in base |radix| and updates the internal cursor. + void AppendNumber(uintptr_t number, int radix = 10, int width = 0, char ch = ' ') + { + int digits = 0; + + if (radix == 16) { + // Optimize output of hex numbers. + + uintptr_t reverse = 0; + int length = 0; + do { + reverse <<= 4; + reverse |= number & 0xf; + number >>= 4; + ++length; + } while (number > 0); + + for (int index = 0; index < length && Cursor_ + digits < End_; ++index) { + unsigned int modulus = reverse & 0xf; + Cursor_[digits] = (modulus < 10 ? '0' + modulus : 'a' + modulus - 10); + ++digits; + reverse >>= 4; + } + } else { + while (Cursor_ + digits < End_) { + const int modulus = number % radix; + number /= radix; + Cursor_[digits] = (modulus < 10 ? '0' + modulus : 'a' + modulus - 10); + ++digits; + if (number == 0) { + break; + } + } + + // Reverse the bytes written. + std::reverse(Cursor_, Cursor_ + digits); + } + + if (digits < width) { + auto delta = width - digits; + std::copy(Cursor_, Cursor_ + digits, Cursor_ + delta); + std::fill(Cursor_, Cursor_ + delta, ch); + Cursor_ += width; + } else { + Cursor_ += digits; + } + } + + //! Formats |number| as hexadecimal number and updates the internal cursor. + //! Padding will be added in front if needed. + void AppendNumberAsHexWithPadding(uintptr_t number, int width) + { + char* begin = Cursor_; + AppendString("0x"); + AppendNumber(number, 16); + // Move to right and add padding in front if needed. + if (Cursor_ < begin + width) { + auto delta = begin + width - Cursor_; + std::copy(begin, Cursor_, begin + delta); + std::fill(begin, begin + delta, ' '); + Cursor_ = begin + width; + } + } + + //! Formats |guid| and updates the internal cursor. + void AppendGuid(TGuid guid) + { + if (Y_LIKELY(End_ - Cursor_ >= MaxGuidStringSize)) { + // Fast path. + Cursor_ = WriteGuidToBuffer(Cursor_, guid); + } else { + // Slow path. + std::array<char, MaxGuidStringSize> buffer; + auto* end = WriteGuidToBuffer(buffer.data(), guid); + AppendString(TStringBuf(buffer.data(), end)); + } + } + + //! Resets the underlying cursor. + void Reset() + { + Cursor_ = Begin_; + } + + TStringBuf GetBuffer() const + { + return {Begin_, Cursor_}; + } + +private: + char* const Begin_; + char* Cursor_; + char* const End_; + +}; + +template <size_t N> +class TRawFormatter + : public TBaseFormatter +{ +public: + TRawFormatter() + : TBaseFormatter(Buffer_, N) + { } + + TRawFormatter(char* buffer, int length) + : TBaseFormatter(buffer, length) + { } + +private: + char Buffer_[N]; + +}; + +//////////////////////////////////////////////////////////////////////////////// + +} // namespace NYT + |