#include "config.h"
#include "RAMSize.h"
#include "StdLibExtras.h"
#include <mutex>
#if OS(DARWIN)
#import <dispatch/dispatch.h>
#import <mach/host_info.h>
#import <mach/mach.h>
#import <mach/mach_error.h>
#import <math.h>
#elif OS(UNIX)
#include <unistd.h>
#elif OS(WINDOWS)
#include <windows.h>
#endif
namespace WTF {
static const size_t ramSizeGuess = 512 * MB;
static size_t computeRAMSize()
{
#if PLATFORM(IOS_SIMULATOR)
return ramSizeGuess;
#elif OS(DARWIN)
host_basic_info_data_t hostInfo;
mach_port_t host = mach_host_self();
mach_msg_type_number_t count = HOST_BASIC_INFO_COUNT;
kern_return_t r = host_info(host, HOST_BASIC_INFO, (host_info_t)&hostInfo, &count);
mach_port_deallocate(mach_task_self(), host);
if (r != KERN_SUCCESS) {
LOG_ERROR("%s : host_info(%d) : %s.\n", __FUNCTION__, r, mach_error_string(r));
return ramSizeGuess;
}
if (hostInfo.max_mem > std::numeric_limits<size_t>::max())
return std::numeric_limits<size_t>::max();
size_t sizeAccordingToKernel = static_cast<size_t>(hostInfo.max_mem);
size_t multiple = 128 * MB;
return ((sizeAccordingToKernel + multiple - 1) / multiple) * multiple;
#elif OS(UNIX)
long pages = sysconf(_SC_PHYS_PAGES);
long pageSize = sysconf(_SC_PAGE_SIZE);
if (pages == -1 || pageSize == -1)
return ramSizeGuess;
return pages * pageSize;
#elif OS(WINDOWS)
MEMORYSTATUSEX status;
status.dwLength = sizeof(status);
bool result = GlobalMemoryStatusEx(&status);
if (!result)
return ramSizeGuess;
return status.ullTotalPhys;
#endif
}
size_t ramSize()
{
static size_t ramSize;
static std::once_flag onceFlag;
std::call_once(onceFlag, [] {
ramSize = computeRAMSize();
});
return ramSize;
}
}