intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 129 insertions, 0 deletions

diff --git a/library/cpp/yt/string/string_builder-inl.h b/library/cpp/yt/string/string_builder-inl.h
new file mode 100644
index 0000000000..151fcabf7f
--- /dev/null
+++ b/library/cpp/yt/string/string_builder-inl.h
@@ -0,0 +1,129 @@
+#ifndef STRING_BUILDER_INL_H_
+#error "Direct inclusion of this file is not allowed, include string.h"
+// For the sake of sane code completion.
+#include "string_builder.h"
+#endif
+
+#include <library/cpp/yt/assert/assert.h>
+
+namespace NYT {
+
+////////////////////////////////////////////////////////////////////////////////
+
+inline char* TStringBuilderBase::Preallocate(size_t size)
+{
+    if (Y_UNLIKELY(End_ - Current_ < static_cast<ssize_t>(size))) {
+        size_t length = GetLength();
+        auto newLength = std::max(length + size, MinBufferLength);
+        DoPreallocate(newLength);
+        Current_ = Begin_ + length;
+    }
+    return Current_;
+}
+
+inline size_t TStringBuilderBase::GetLength() const
+{
+    return Current_ ? Current_ - Begin_ : 0;
+}
+
+inline TStringBuf TStringBuilderBase::GetBuffer() const
+{
+    return TStringBuf(Begin_, Current_);
+}
+
+inline void TStringBuilderBase::Advance(size_t size)
+{
+    Current_ += size;
+    YT_ASSERT(Current_ <= End_);
+}
+
+inline void TStringBuilderBase::AppendChar(char ch)
+{
+    *Preallocate(1) = ch;
+    Advance(1);
+}
+
+inline void TStringBuilderBase::AppendChar(char ch, int n)
+{
+    YT_ASSERT(n >= 0);
+    if (Y_LIKELY(0 != n)) {
+        char* dst = Preallocate(n);
+        ::memset(dst, ch, n);
+        Advance(n);
+    }
+}
+
+inline void TStringBuilderBase::AppendString(TStringBuf str)
+{
+    if (Y_LIKELY(str)) {
+        char* dst = Preallocate(str.length());
+        ::memcpy(dst, str.begin(), str.length());
+        Advance(str.length());
+    }
+}
+
+inline void TStringBuilderBase::AppendString(const char* str)
+{
+    AppendString(TStringBuf(str));
+}
+
+inline void TStringBuilderBase::Reset()
+{
+    Begin_ = Current_ = End_ = nullptr;
+    DoReset();
+}
+
+template <class... TArgs>
+void TStringBuilderBase::AppendFormat(TStringBuf format, TArgs&& ... args)
+{
+    Format(this, format, std::forward<TArgs>(args)...);
+}
+
+template <size_t Length, class... TArgs>
+void TStringBuilderBase::AppendFormat(const char (&format)[Length], TArgs&& ... args)
+{
+    Format(this, format, std::forward<TArgs>(args)...);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+inline TString TStringBuilder::Flush()
+{
+    Buffer_.resize(GetLength());
+    auto result = std::move(Buffer_);
+    Reset();
+    return result;
+}
+
+inline void TStringBuilder::DoReset()
+{
+    Buffer_ = {};
+}
+
+inline void TStringBuilder::DoPreallocate(size_t newLength)
+{
+    Buffer_.ReserveAndResize(newLength);
+    auto capacity = Buffer_.capacity();
+    Buffer_.ReserveAndResize(capacity);
+    Begin_ = &*Buffer_.begin();
+    End_ = Begin_ + capacity;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+inline void FormatValue(TStringBuilderBase* builder, const TStringBuilder& value, TStringBuf /*format*/)
+{
+    builder->AppendString(value.GetBuffer());
+}
+
+template <class T>
+TString ToStringViaBuilder(const T& value, TStringBuf spec)
+{
+    TStringBuilder builder;
+    FormatValue(&builder, value, spec);
+    return builder.Flush();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NYT