ClickHouse/src/IO/ReadBufferFromFile.cpp
2023-12-18 10:40:02 +01:00

98 lines
2.2 KiB
C++

#include <fcntl.h>
#include <IO/ReadBufferFromFile.h>
#include <IO/WriteHelpers.h>
#include <Common/ProfileEvents.h>
#include <base/defines.h>
#include <cerrno>
namespace ProfileEvents
{
extern const Event FileOpen;
}
namespace DB
{
namespace ErrorCodes
{
extern const int FILE_DOESNT_EXIST;
extern const int CANNOT_OPEN_FILE;
extern const int CANNOT_CLOSE_FILE;
}
ReadBufferFromFile::ReadBufferFromFile(
const std::string & file_name_,
size_t buf_size,
int flags,
char * existing_memory,
size_t alignment,
std::optional<size_t> file_size_,
ThrottlerPtr throttler_)
: ReadBufferFromFileDescriptor(-1, buf_size, existing_memory, alignment, file_size_, throttler_)
, file_name(file_name_)
{
ProfileEvents::increment(ProfileEvents::FileOpen);
#ifdef OS_DARWIN
bool o_direct = (flags != -1) && (flags & O_DIRECT);
if (o_direct)
flags = flags & ~O_DIRECT;
#endif
fd = ::open(file_name.c_str(), flags == -1 ? O_RDONLY | O_CLOEXEC : flags | O_CLOEXEC);
if (-1 == fd)
ErrnoException::throwFromPath(
errno == ENOENT ? ErrorCodes::FILE_DOESNT_EXIST : ErrorCodes::CANNOT_OPEN_FILE, file_name, "Cannot open file {}", file_name);
#ifdef OS_DARWIN
if (o_direct)
{
if (fcntl(fd, F_NOCACHE, 1) == -1)
ErrnoException::throwFromPath(ErrorCodes::CANNOT_OPEN_FILE, file_name, "Cannot set F_NOCACHE on file {}", file_name);
}
#endif
}
ReadBufferFromFile::ReadBufferFromFile(
int & fd_,
const std::string & original_file_name,
size_t buf_size,
char * existing_memory,
size_t alignment,
std::optional<size_t> file_size_,
ThrottlerPtr throttler_)
: ReadBufferFromFileDescriptor(fd_, buf_size, existing_memory, alignment, file_size_, throttler_)
, file_name(original_file_name.empty() ? "(fd = " + toString(fd_) + ")" : original_file_name)
{
fd_ = -1;
}
ReadBufferFromFile::~ReadBufferFromFile()
{
if (fd < 0)
return;
int err = ::close(fd);
chassert(!err || errno == EINTR);
}
void ReadBufferFromFile::close()
{
if (fd < 0)
return;
if (0 != ::close(fd))
throw Exception(ErrorCodes::CANNOT_CLOSE_FILE, "Cannot close file");
fd = -1;
metric_increment.destroy();
}
}