ClickHouse/src/Common/PipeFDs.cpp
2020-06-07 20:29:34 +03:00

114 lines
2.9 KiB
C++

#include <Common/PipeFDs.h>
#include <Common/Exception.h>
#include <Common/formatReadable.h>
#include <common/logger_useful.h>
#include <common/errnoToString.h>
#include <unistd.h>
#include <fcntl.h>
#include <string>
#include <algorithm>
namespace DB
{
namespace ErrorCodes
{
extern const int CANNOT_PIPE;
extern const int CANNOT_FCNTL;
extern const int LOGICAL_ERROR;
}
void LazyPipeFDs::open()
{
for (int & fd : fds_rw)
if (fd >= 0)
throw Exception("Pipe is already opened", ErrorCodes::LOGICAL_ERROR);
#ifndef __APPLE__
if (0 != pipe2(fds_rw, O_CLOEXEC))
throwFromErrno("Cannot create pipe", ErrorCodes::CANNOT_PIPE);
#else
if (0 != pipe(fds_rw))
throwFromErrno("Cannot create pipe", ErrorCodes::CANNOT_PIPE);
if (0 != fcntl(fds_rw[0], F_SETFD, FD_CLOEXEC))
throwFromErrno("Cannot setup auto-close on exec for read end of pipe", ErrorCodes::CANNOT_FCNTL);
if (0 != fcntl(fds_rw[1], F_SETFD, FD_CLOEXEC))
throwFromErrno("Cannot setup auto-close on exec for write end of pipe", ErrorCodes::CANNOT_FCNTL);
#endif
}
void LazyPipeFDs::close()
{
for (int & fd : fds_rw)
{
if (fd < 0)
continue;
if (0 != ::close(fd))
throwFromErrno("Cannot close pipe", ErrorCodes::CANNOT_PIPE);
fd = -1;
}
}
PipeFDs::PipeFDs()
{
open();
}
LazyPipeFDs::~LazyPipeFDs()
{
try
{
close();
}
catch (...)
{
tryLogCurrentException(__PRETTY_FUNCTION__);
}
}
void LazyPipeFDs::setNonBlocking()
{
int flags = fcntl(fds_rw[1], F_GETFL, 0);
if (-1 == flags)
throwFromErrno("Cannot get file status flags of pipe", ErrorCodes::CANNOT_FCNTL);
if (-1 == fcntl(fds_rw[1], F_SETFL, flags | O_NONBLOCK))
throwFromErrno("Cannot set non-blocking mode of pipe", ErrorCodes::CANNOT_FCNTL);
}
void LazyPipeFDs::tryIncreaseSize(int desired_size)
{
#if defined(OS_LINUX)
Poco::Logger * log = &Poco::Logger::get("Pipe");
/** Increase pipe size to avoid slowdown during fine-grained trace collection.
*/
int pipe_size = fcntl(fds_rw[1], F_GETPIPE_SZ);
if (-1 == pipe_size)
{
if (errno == EINVAL)
{
LOG_INFO(log, "Cannot get pipe capacity, {}. Very old Linux kernels have no support for this fcntl.", errnoToString(ErrorCodes::CANNOT_FCNTL));
/// It will work nevertheless.
}
else
throwFromErrno("Cannot get pipe capacity", ErrorCodes::CANNOT_FCNTL);
}
else
{
for (errno = 0; errno != EPERM && pipe_size < desired_size; pipe_size *= 2)
if (-1 == fcntl(fds_rw[1], F_SETPIPE_SZ, pipe_size * 2) && errno != EPERM)
throwFromErrno("Cannot increase pipe capacity to " + std::to_string(pipe_size * 2), ErrorCodes::CANNOT_FCNTL);
LOG_TRACE(log, "Pipe capacity is {}", ReadableSize(std::min(pipe_size, desired_size)));
}
#else
(void)desired_size;
#endif
}
}