allocator_traits.h

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/** @file include/detail/ut/allocator_traits.h
    Simple allocator traits.
 */
 
#ifndef detail_ut_allocator_traits_h
#define detail_ut_allocator_traits_h
 
#if defined(_WIN32) && defined(MYSQL_SERVER)
#include <mutex>
#include "jemalloc_win.h"
#endif /* _WIN32 && MYSQL_SERVER */
 
namespace ut {
namespace detail {
 
#if defined(_WIN32) && defined(MYSQL_SERVER)
/** Wrapper functions for using jemalloc on Windows.
If jemalloc.dll is available and its use is enabled, the
init_malloc_pointers function will set up the pfn_malloc, pfn_calloc,
pfn_realloc and pfn_free function pointers to point to the corresponding
jemalloc functions. Otherwise they will point to the standard MSVC library
implementations of the malloc, calloc etc. */
 
inline void *malloc(size_t nbytes) {
  std::call_once(mysys::detail::init_malloc_pointers_flag,
                 mysys::detail::init_malloc_pointers);
  return mysys::detail::pfn_malloc(nbytes);
}
inline void *calloc(size_t nbytes) {
  std::call_once(mysys::detail::init_malloc_pointers_flag,
                 mysys::detail::init_malloc_pointers);
  return mysys::detail::pfn_calloc(1, nbytes);
}
inline void *realloc(void *ptr, size_t nbytes) {
  std::call_once(mysys::detail::init_malloc_pointers_flag,
                 mysys::detail::init_malloc_pointers);
  return mysys::detail::pfn_realloc(ptr, nbytes);
}
inline void free(void *ptr) {
  std::call_once(mysys::detail::init_malloc_pointers_flag,
                 mysys::detail::init_malloc_pointers);
  mysys::detail::pfn_free(ptr);
}
#else
inline void *malloc(size_t nbytes) { return std::malloc(nbytes); }
inline void *calloc(size_t nbytes) { return std::calloc(1, nbytes); }
inline void *realloc(void *ptr, size_t nbytes) {
  return std::realloc(ptr, nbytes);
}
inline void free(void *ptr) { std::free(ptr); }
#endif /* _WIN32 && MYSQL_SERVER */
 
/** Simple allocator traits. */
template <bool Pfs_instrumented>
struct allocator_traits {
  // Is allocator PFS instrumented or not
  static constexpr auto is_pfs_instrumented_v = Pfs_instrumented;
};
 
/** Simple wrapping type around malloc, calloc and friends.*/
struct Alloc_fn {
  static void *malloc(size_t nbytes) { return ut::detail::malloc(nbytes); }
 
  static void *calloc(size_t nbytes) { return ut::detail::calloc(nbytes); }
 
  template <bool Zero_initialized>
  static void *alloc(size_t size) {
    if constexpr (Zero_initialized)
      return Alloc_fn::calloc(size);
    else
      return Alloc_fn::malloc(size);
  }
 
  static void *realloc(void *ptr, size_t nbytes) {
    return ut::detail::realloc(ptr, nbytes);
  }
 
  static void free(void *ptr) { ut::detail::free(ptr); }
};
 
}  // namespace detail
}  // namespace ut
 
#endif