all repos — slstatus @ 39ee31c2425d3ff79f88808cabf44c305d6849ab

my build of slstatus (tools.suckless.org/slstatus/)

components/ram.c

/* See LICENSE file for copyright and license details. */
#include <stdio.h>

#include "../util.h"

#if defined(__linux__)
	const char *
	ram_free(void)
	{
		long free;

		return (pscanf("/proc/meminfo", "MemFree: %ld kB\n", &free) == 1) ?
		       bprintf("%f", (float)free / 1024 / 1024) : NULL;
	}

	const char *
	ram_perc(void)
	{
		long total, free, buffers, cached;

		return (pscanf("/proc/meminfo",
		               "MemTotal: %ld kB\n"
		               "MemFree: %ld kB\n"
		               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
		               "Cached: %ld kB\n",
		               &total, &free, &buffers, &buffers, &cached) == 5) ?
		       bprintf("%d", 100 * ((total - free) - (buffers + cached)) /
		               total) :
		       NULL;
	}

	const char *
	ram_total(void)
	{
		long total;

		return (pscanf("/proc/meminfo", "MemTotal: %ld kB\n", &total) == 1) ?
		       bprintf("%f", (float)total / 1024 / 1024) : NULL;
	}

	const char *
	ram_used(void)
	{
		long total, free, buffers, cached;

		return (pscanf("/proc/meminfo",
		               "MemTotal: %ld kB\n"
		               "MemFree: %ld kB\n"
		               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
		               "Cached: %ld kB\n",
		               &total, &free, &buffers, &buffers, &cached) == 5) ?
		       bprintf("%f", (float)(total - free - buffers - cached) /
		               1024 / 1024) :
		       NULL;
	}
#elif defined(__OpenBSD__)
	#include <stdlib.h>
	#include <sys/sysctl.h>
	#include <sys/types.h>
	#include <unistd.h>

	#define LOG1024 	10
	#define pagetok(size, pageshift) ((size) << (pageshift - LOG1024))

	inline int
	load_uvmexp(struct uvmexp *uvmexp)
	{
		int uvmexp_mib[] = {CTL_VM, VM_UVMEXP};
		size_t size;

		size = sizeof(*uvmexp);

		return sysctl(uvmexp_mib, 2, uvmexp, &size, NULL, 0) >= 0 ? 1 : 0;
	}

	const char *
	ram_free(void)
	{
		struct uvmexp uvmexp;
		float free;
		int free_pages;

		if (load_uvmexp(&uvmexp)) {
			free_pages = uvmexp.npages - uvmexp.active;
			free = (float)(pagetok(free_pages, uvmexp.pageshift)) / 1024 / 1024;
			return bprintf("%f", free);
		}

		return NULL;
	}

	const char *
	ram_perc(void)
	{
		struct uvmexp uvmexp;
		int percent;

		if (load_uvmexp(&uvmexp)) {
			percent = uvmexp.active * 100 / uvmexp.npages;
			return bprintf("%d", percent);
		}

		return NULL;
	}

	const char *
	ram_total(void)
	{
		struct uvmexp uvmexp;
		float total;

		if (load_uvmexp(&uvmexp)) {
			total = (float)(pagetok(uvmexp.npages, uvmexp.pageshift)) / 1024 / 1024;
			return bprintf("%f", total);
		}

		return NULL;
	}

	const char *
	ram_used(void)
	{
		struct uvmexp uvmexp;
		float used;

		if (load_uvmexp(&uvmexp)) {
			used = (float)(pagetok(uvmexp.active, uvmexp.pageshift)) / 1024 / 1024;
			return bprintf("%f", used);
		}

		return NULL;
	}
#endif