Skip to content

Instantly share code, notes, and snippets.

@renbaoshuo
Created May 2, 2023 12:44
Show Gist options
  • Star 0 You must be signed in to star a gist
  • Fork 0 You must be signed in to fork a gist
  • Save renbaoshuo/07aa76a414210520a3f681c7a0656d80 to your computer and use it in GitHub Desktop.
Save renbaoshuo/07aa76a414210520a3f681c7a0656d80 to your computer and use it in GitHub Desktop.
#include <iostream>
#include <cpuid.h>
#include <stdint.h>
#if defined(_WIN32)
#include <Windows.h>
#elif defined(__unix__) || defined(__unix) || defined(unix) || (defined(__APPLE__) && defined(__MACH__))
#include <sys/param.h>
#include <sys/types.h>
#include <unistd.h>
#if defined(BSD)
#include <sys/sysctl.h>
#endif
#else
#error "Unable to define getMemorySize() for an unknown OS."
#endif
static void cpuid(uint32_t func, uint32_t sub, uint32_t data[4]) {
__cpuid_count(func, sub, data[0], data[1], data[2], data[3]);
}
/**
* Returns the size of physical memory (RAM) in bytes.
*/
size_t getMemorySize() {
#if defined(_WIN32) && (defined(__CYGWIN__) || defined(__CYGWIN32__))
/* Cygwin under Windows. ------------------------------------ */
/* New 64-bit MEMORYSTATUSEX isn't available. Use old 32.bit */
MEMORYSTATUS status;
status.dwLength = sizeof(status);
GlobalMemoryStatus(&status);
return (size_t)status.dwTotalPhys;
#elif defined(_WIN32)
/* Windows. ------------------------------------------------- */
/* Use new 64-bit MEMORYSTATUSEX, not old 32-bit MEMORYSTATUS */
MEMORYSTATUSEX status;
status.dwLength = sizeof(status);
GlobalMemoryStatusEx(&status);
return (size_t)status.ullTotalPhys;
#elif defined(__unix__) || defined(__unix) || defined(unix) || (defined(__APPLE__) && defined(__MACH__))
/* UNIX variants. ------------------------------------------- */
/* Prefer sysctl() over sysconf() except sysctl() HW_REALMEM and HW_PHYSMEM */
#if defined(CTL_HW) && (defined(HW_MEMSIZE) || defined(HW_PHYSMEM64))
int mib[2];
mib[0] = CTL_HW;
#if defined(HW_MEMSIZE)
mib[1] = HW_MEMSIZE; /* OSX. --------------------- */
#elif defined(HW_PHYSMEM64)
mib[1] = HW_PHYSMEM64; /* NetBSD, OpenBSD. --------- */
#endif
int64_t size = 0; /* 64-bit */
size_t len = sizeof(size);
if (sysctl(mib, 2, &size, &len, NULL, 0) == 0)
return (size_t)size;
return 0L; /* Failed? */
#elif defined(_SC_AIX_REALMEM)
/* AIX. ----------------------------------------------------- */
return (size_t)sysconf(_SC_AIX_REALMEM) * (size_t)1024L;
#elif defined(_SC_PHYS_PAGES) && defined(_SC_PAGESIZE)
/* FreeBSD, Linux, OpenBSD, and Solaris. -------------------- */
return (size_t)sysconf(_SC_PHYS_PAGES) * (size_t)sysconf(_SC_PAGESIZE);
#elif defined(_SC_PHYS_PAGES) && defined(_SC_PAGE_SIZE)
/* Legacy. -------------------------------------------------- */
return (size_t)sysconf(_SC_PHYS_PAGES) * (size_t)sysconf(_SC_PAGE_SIZE);
#elif defined(CTL_HW) && (defined(HW_PHYSMEM) || defined(HW_REALMEM))
/* DragonFly BSD, FreeBSD, NetBSD, OpenBSD, and OSX. -------- */
int mib[2];
mib[0] = CTL_HW;
#if defined(HW_REALMEM)
mib[1] = HW_REALMEM; /* FreeBSD. ----------------- */
#elif defined(HW_PYSMEM)
mib[1] = HW_PHYSMEM; /* Others. ------------------ */
#endif
unsigned int size = 0; /* 32-bit */
size_t len = sizeof(size);
if (sysctl(mib, 2, &size, &len, NULL, 0) == 0)
return (size_t)size;
return 0L; /* Failed? */
#endif /* sysctl and sysconf variants */
#else
return 0L; /* Unknown OS. */
#endif
}
int main() {
uint32_t data[4];
char str[48];
for (int i = 0; i < 3; ++i) {
cpuid(0x80000002 + i, 0, data);
for (int j = 0; j < 4; ++j) {
reinterpret_cast<uint32_t*>(str)[i * 4 + j] = data[j];
}
}
size_t memorySize = getMemorySize();
std::cout << "CPU: " << str << std::endl;
std::cout << "Memory: " << (memorySize / (1024 * 1024)) << "MiB" << std::endl;
return 0;
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment