/* 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",
		               "MemTotal: %ld kB\n"
		               "MemFree: %ld kB\n"
		               "MemAvailable: %ld kB\n",
		               &free, &free, &free) == 3) ?
		       fmt_human_2(free * 1024, "B") : 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) ?
		       fmt_human_2(total * 1024, "B") : 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) ?
		       fmt_human_2((total - free - buffers - cached) * 1024, "B") : 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;
		int free_pages;

		if (load_uvmexp(&uvmexp)) {
			free_pages = uvmexp.npages - uvmexp.active;
			return fmt_human_2(pagetok(free_pages, uvmexp.pageshift) * 1024, "B");
		}

		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;

		if (load_uvmexp(&uvmexp)) {
			return fmt_human_2(pagetok(uvmexp.npages, uvmexp.pageshift) * 1024, "B");
		}

		return NULL;
	}

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

		if (load_uvmexp(&uvmexp)) {
			return fmt_human_2(pagetok(uvmexp.active, uvmexp.pageshift) * 1024, "B");
		}

		return NULL;
	}
#endif