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#include "file.h"
#include <util/memory/blob.h>
#include <util/generic/yexception.h>
TUnbufferedFileInput::TUnbufferedFileInput(const TString& path)
: File_(path, OpenExisting | RdOnly | Seq)
{
if (!File_.IsOpen()) {
ythrow TIoException() << "file " << path << " not open";
}
}
TUnbufferedFileInput::TUnbufferedFileInput(const TFile& file)
: File_(file)
{
if (!File_.IsOpen()) {
ythrow TIoException() << "file (" << file.GetName() << ") not open";
}
}
size_t TUnbufferedFileInput::DoRead(void* buf, size_t len) {
return File_.ReadOrFail(buf, len);
}
size_t TUnbufferedFileInput::DoSkip(size_t len) {
if (len < 384) {
/* Base implementation calls DoRead, which results in one system call
* instead of three as in fair skip implementation. For small sizes
* actually doing one read is cheaper. Experiments show that the
* border that separates two implementations performance-wise lies
* in the range of 384-512 bytes (assuming that the file is in OS cache). */
return IInputStream::DoSkip(len);
}
/* TFile::Seek can seek beyond the end of file, so we need to do
* size check here. */
i64 size = File_.GetLength();
i64 oldPos = File_.GetPosition();
i64 newPos = File_.Seek(Min<i64>(size, oldPos + len), sSet);
return newPos - oldPos;
}
TUnbufferedFileOutput::TUnbufferedFileOutput(const TString& path)
: File_(path, CreateAlways | WrOnly | Seq)
{
if (!File_.IsOpen()) {
ythrow TFileError() << "can not open " << path;
}
}
TUnbufferedFileOutput::TUnbufferedFileOutput(const TFile& file)
: File_(file)
{
if (!File_.IsOpen()) {
ythrow TIoException() << "closed file(" << file.GetName() << ") passed";
}
}
TUnbufferedFileOutput::~TUnbufferedFileOutput() = default;
void TUnbufferedFileOutput::DoWrite(const void* buf, size_t len) {
File_.Write(buf, len);
}
void TUnbufferedFileOutput::DoFlush() {
if (File_.IsOpen()) {
File_.Flush();
}
}
class TMappedFileInput::TImpl: public TBlob {
public:
inline TImpl(TFile file)
: TBlob(TBlob::FromFile(file))
{
}
inline ~TImpl() = default;
};
TMappedFileInput::TMappedFileInput(const TFile& file)
: TMemoryInput(nullptr, 0)
, Impl_(new TImpl(file))
{
Reset(Impl_->Data(), Impl_->Size());
}
TMappedFileInput::TMappedFileInput(const TString& path)
: TMemoryInput(nullptr, 0)
, Impl_(new TImpl(TFile(path, OpenExisting | RdOnly)))
{
Reset(Impl_->Data(), Impl_->Size());
}
TMappedFileInput::~TMappedFileInput() = default;
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