ClickHouse/base/base/mremap.cpp
Robert Schulze 1b81bb49b4
Enable clang-tidy modernize-deprecated-headers & hicpp-deprecated-headers
Official docs:

  Some headers from C library were deprecated in C++ and are no longer
  welcome in C++ codebases. Some have no effect in C++. For more details
  refer to the C++ 14 Standard [depr.c.headers] section. This check
  replaces C standard library headers with their C++ alternatives and
  removes redundant ones.
2022-05-09 08:23:33 +02:00

33 lines
733 B
C++

#include <base/mremap.h>
#include <cstddef>
#include <cstdlib>
#include <cstring>
#include <cerrno>
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)
{
/// No actual shrink
if (new_size < old_size)
return old_address;
if (!(flags & MREMAP_MAYMOVE))
{
errno = ENOMEM;
return MAP_FAILED;
}
void * new_address = mmap(nullptr, new_size, mmap_prot, mmap_flags, mmap_fd, mmap_offset);
if (MAP_FAILED == new_address)
return MAP_FAILED;
memcpy(new_address, old_address, old_size);
if (munmap(old_address, old_size))
abort();
return new_address;
}