ClickHouse/base/base/mremap.h

84 lines
1.7 KiB
C++

#pragma once
#include <cstddef>
#include <sys/types.h>
#include <sys/mman.h>
#ifdef MREMAP_MAYMOVE
#define HAS_MREMAP 1
#else
#define HAS_MREMAP 0
#endif
/// You can forcely disable mremap by defining DISABLE_MREMAP to 1 before including this file.
#ifndef DISABLE_MREMAP
#if HAS_MREMAP
#define DISABLE_MREMAP 0
#else
#define DISABLE_MREMAP 1
#endif
#endif
/// Implement mremap with mmap/memcpy/munmap.
void * mremap_fallback(
void * old_address,
size_t old_size,
size_t new_size,
int flags,
int mmap_prot,
int mmap_flags,
int mmap_fd,
off_t mmap_offset);
#if !HAS_MREMAP
#define MREMAP_MAYMOVE 1
inline void * mremap(
void * old_address,
size_t old_size,
size_t new_size,
int flags = 0,
int mmap_prot = 0,
int mmap_flags = 0,
int mmap_fd = -1,
off_t mmap_offset = 0)
{
return mremap_fallback(old_address, old_size, new_size, flags, mmap_prot, mmap_flags, mmap_fd, mmap_offset);
}
#endif
inline void * clickhouse_mremap(
void * old_address,
size_t old_size,
size_t new_size,
int flags = 0,
[[maybe_unused]] int mmap_prot = 0,
[[maybe_unused]] int mmap_flags = 0,
[[maybe_unused]] int mmap_fd = -1,
[[maybe_unused]] off_t mmap_offset = 0)
{
#if DISABLE_MREMAP
return mremap_fallback(old_address, old_size, new_size, flags, mmap_prot, mmap_flags, mmap_fd, mmap_offset);
#else
return mremap(
old_address,
old_size,
new_size,
flags
#if !defined(MREMAP_FIXED)
,
mmap_prot,
mmap_flags,
mmap_fd,
mmap_offset
#endif
);
#endif
}