toaruos/userspace/core/free.c
2015-06-24 11:06:10 -07:00

81 lines
1.5 KiB
C

/* vim: tabstop=4 shiftwidth=4 noexpandtab
* This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2015 Kevin Lange
*
* free - Show free / used / total RAM
*/
#include <stdio.h>
#include <getopt.h>
void show_usage(int argc, char * argv[]) {
printf(
"free - show available memory\n"
"\n"
"usage: %s [-utk?]\n"
"\n"
" -u \033[3mshow used instead of free\033[0m\n"
" -t \033[3minclude a total\033[0m\n"
" -k \033[3muse kilobytes instead of megabytes\033[0m\n"
" -? \033[3mshow this help text\033[0m\n"
"\n", argv[0]);
}
int main(int argc, char * argv[]) {
int show_used = 0;
int use_kilobytes = 0;
int show_total = 0;
if (argc > 1) {
int index, c;
while ((c = getopt(argc, argv, "ktu?")) != -1) {
switch (c) {
case 'u':
show_used = 1;
break;
case 't':
show_total = 1;
break;
case 'k':
use_kilobytes = 1;
break;
case '?':
show_usage(argc, argv);
return 0;
}
}
}
const char * unit = "kB";
FILE * f = fopen("/proc/meminfo", "r");
if (!f) return 1;
int total, free, used;
fscanf(f, "MemTotal: %d kB\nMemFree: %d kB\n", &total, &free);
used = total - free;
if (!use_kilobytes) {
unit = "MB";
free /= 1024;
used /= 1024;
total /= 1024;
}
if (show_used) {
printf("%d %s", used, unit);
} else {
printf("%d %s", free, unit);
}
if (show_total) {
printf(" / %d %s", total, unit);
}
printf("\n");
return 0;
}