FileOutputBuffer.cpp [plain text]
#include "llvm/Support/FileOutputBuffer.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/system_error.h"
using llvm::sys::fs::mapped_file_region;
namespace llvm {
FileOutputBuffer::FileOutputBuffer(mapped_file_region * R,
StringRef Path, StringRef TmpPath)
: Region(R)
, FinalPath(Path)
, TempPath(TmpPath) {
}
FileOutputBuffer::~FileOutputBuffer() {
sys::fs::remove(Twine(TempPath));
}
error_code FileOutputBuffer::create(StringRef FilePath,
size_t Size,
OwningPtr<FileOutputBuffer> &Result,
unsigned Flags) {
sys::fs::file_status Stat;
error_code EC = sys::fs::status(FilePath, Stat);
switch (Stat.type()) {
case sys::fs::file_type::file_not_found:
break;
case sys::fs::file_type::regular_file: {
}
break;
default:
if (EC)
return EC;
else
return make_error_code(errc::operation_not_permitted);
}
EC = sys::fs::remove(FilePath);
if (EC)
return EC;
unsigned Mode = sys::fs::all_read | sys::fs::all_write;
if (Flags & F_executable)
Mode |= sys::fs::all_exe;
SmallString<128> TempFilePath;
int FD;
EC = sys::fs::createUniqueFile(Twine(FilePath) + ".tmp%%%%%%%", FD,
TempFilePath, Mode);
if (EC)
return EC;
OwningPtr<mapped_file_region> MappedFile(new mapped_file_region(
FD, true, mapped_file_region::readwrite, Size, 0, EC));
if (EC)
return EC;
Result.reset(new FileOutputBuffer(MappedFile.get(), FilePath, TempFilePath));
if (Result)
MappedFile.take();
return error_code::success();
}
error_code FileOutputBuffer::commit(int64_t NewSmallerSize) {
Region.reset(0);
if ( NewSmallerSize != -1 ) {
error_code EC = sys::fs::resize_file(Twine(TempPath), NewSmallerSize);
if (EC)
return EC;
}
return sys::fs::rename(Twine(TempPath), Twine(FinalPath));
}
}