--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toys/other/vmstat.c	Sat Aug 25 14:25:22 2012 -0500
@@ -0,0 +1,191 @@
+/* vi: set sw=4 ts=4:
+ *
+ * vmstat.c - Report virtual memory statistics.
+ *
+ * Copyright 2012 Elie De Brauwer <eliedebrauwer@gmail.com>
+ *
+ * Not in SUSv4.
+
+USE_VMSTAT(NEWTOY(vmstat, ">2n", TOYFLAG_BIN))
+
+config VMSTAT
+	bool "vmstat"
+	default y
+	help
+	  usage: vmstat [-n] [delay [count]]
+	  -n Display the header only once
+	  delay The delay between updates in seconds, when not specified
+	        the average since boot is displayed.
+	  count Number of updates to display, the default is inifinite.
+*/
+
+#include "toys.h"
+
+void read_proc_stat(unsigned int * proc_running, unsigned int * proc_blocked,
+		uint64_t * sys_irq, uint64_t * sys_ctxt,
+		uint64_t * cpu_user, uint64_t * cpu_sys, uint64_t * cpu_idle, uint64_t * cpu_wait)
+{
+	char * off;
+	uint64_t c_user, c_nice, c_sys, c_irq, c_sirq;
+	int fd = xopen("/proc/stat", O_RDONLY);
+	size_t s = xread(fd, toybuf, sizeof(toybuf)-1);
+	toybuf[s] = 0;
+	if ( s == sizeof(toybuf)-1)
+		error_exit("/proc/stat is too large");
+
+	off = strstr(toybuf, "cpu ");
+	// Ignoring steal and guest fields for now.
+	if (off) sscanf(off, "cpu  %"PRIu64" %"PRIu64" %"PRIu64" %"PRIu64 \
+		" %"PRIu64" %"PRIu64" %"PRIu64, &c_user, &c_nice, &c_sys, cpu_idle,
+		cpu_wait, &c_irq, &c_sirq);
+	*cpu_user = c_user + c_nice;
+	*cpu_sys = c_sys + c_irq + c_sirq;
+	off = strstr(toybuf, "intr");
+	if (off) sscanf(off, "intr %"PRIu64, sys_irq);
+
+	off = strstr(toybuf, "ctxt");
+	if (off) sscanf(off, "ctxt %"PRIu64, sys_ctxt);
+
+	off = strstr(toybuf, "procs_running");
+	if (off) sscanf(off, "procs_running %u", proc_running);
+	(*proc_running)--; // look, i'm invisible.
+
+	off = strstr(toybuf, "procs_blocked");
+	if (off) sscanf(off, "procs_blocked %u", proc_blocked);
+
+	close(fd);
+}
+
+void read_proc_meminfo(unsigned long * mem_swapped, unsigned long * mem_free,
+			unsigned long * mem_buff, unsigned long * mem_cache)
+{
+	char * off;
+	unsigned long swap_total, swap_free;
+	int fd = xopen("/proc/meminfo", O_RDONLY);
+	size_t s = xread(fd, toybuf, sizeof(toybuf)-1);
+	toybuf[s] = 0;
+	if ( s == sizeof(toybuf)-1)
+		error_exit("/proc/meminfo is too large");
+
+	off = strstr(toybuf, "MemFree");
+	if (off) sscanf(off, "MemFree: %lu kB", mem_free);
+
+	off = strstr(toybuf, "Buffers");
+	if (off) sscanf(off, "Buffers: %lu kB", mem_buff);
+
+	off = strstr(toybuf, "Cached");
+	if (off) sscanf(off, "Cached: %lu kB", mem_cache);
+
+	off = strstr(toybuf, "SwapFree");
+	if (off) sscanf(off, "SwapFree: %lu kB", &swap_free); 
+
+	off = strstr(toybuf, "SwapTotal");
+	if (off) sscanf(off, "SwapTotal: %lu kB", &swap_total);
+	*mem_swapped = swap_total - swap_free;
+
+	close(fd);
+}
+
+void read_proc_vmstat(unsigned long * io_pages_in, unsigned long * io_pages_out,
+			unsigned long * swap_bytes_in, unsigned long * swap_bytes_out)
+{
+	char * off;
+	unsigned long s_pages_in, s_pages_out;
+	unsigned long pagesize_kb = sysconf(_SC_PAGESIZE) / 1024L;
+	int fd = xopen("/proc/vmstat", O_RDONLY);
+	size_t s = xread(fd, toybuf, sizeof(toybuf)-1);
+	toybuf[s] = 0;
+	if ( s == sizeof(toybuf)-1)
+		error_exit("/proc/vmstat is too large");
+
+	off = strstr(toybuf, "pgpgin");
+	if (off) sscanf(off, "pgpgin %lu", io_pages_in);
+
+	off = strstr(toybuf, "pgpgout");
+	if (off) sscanf(off, "pgpgout %lu", io_pages_out);
+
+	off = strstr(toybuf, "pswpin");
+	if (off) sscanf(off, "pswpin %lu", &s_pages_in);
+	*swap_bytes_in = s_pages_in * pagesize_kb;
+
+	off = strstr(toybuf, "pswpout");
+	if (off) sscanf(off, "pswpout %lu", &s_pages_out);
+	*swap_bytes_out = s_pages_out * pagesize_kb;
+
+	close(fd);
+}
+
+void vmstat_main(void)
+{
+	const char fmt[] = "%2u %2u %6lu %6lu %6lu %6lu %4u %4u %5u %5u %4u %4u %2u %2u %2u %2u\n";
+	unsigned int loop_num = 0, loop_max_num = 0, loop_delay = 0;
+	unsigned int running = 0, blocked = 0;
+	unsigned long mem_swap = 0, mem_free = 0, mem_buff = 0, mem_cache = 0;
+	unsigned long io_pages_in[2], io_pages_out[2], swap_bytes_in[2], swap_bytes_out[2];
+	uint64_t sys_irq[2], sys_ctxt[2], cpu_user[2], cpu_sys[2], cpu_idle[2], cpu_wait[2];
+	int first_run = 1;
+	int no_header = toys.optflags & 0x1;
+	unsigned num_rows = 22;
+
+	if (toys.optc >= 1)
+		loop_delay = atoi(toys.optargs[0]);
+	if (toys.optc >= 2)
+		loop_max_num = atoi(toys.optargs[1]);
+
+	if (loop_max_num < 0 || loop_delay < 0)
+		error_exit("Invalid arguments");
+
+	while(1) {
+		uint64_t total_jif;
+		int idx = loop_num%2;
+
+		if(first_run || (!(loop_num % num_rows) && !no_header)) {
+			unsigned rows = 0, cols = 0;
+			terminal_size(&cols, &rows);
+			num_rows = (rows > 3)? rows - 3 : 22;
+			printf("procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----\n");
+			printf(" r  b   swpd   free   buff  cache   si   so	bi	bo   in   cs us sy id wa\n");
+		}
+
+		read_proc_stat(&running, &blocked, &sys_irq[idx], &sys_ctxt[idx], &cpu_user[idx],
+					   &cpu_sys[idx], &cpu_idle[idx], &cpu_wait[idx]);
+		read_proc_meminfo(&mem_swap, &mem_free, &mem_buff, &mem_cache);
+		read_proc_vmstat(&io_pages_in[idx], &io_pages_out[idx], &swap_bytes_in[idx], &swap_bytes_out[idx]);
+
+		if (first_run) {
+			struct sysinfo inf;
+			sysinfo(&inf);
+			first_run = 0;
+			total_jif = cpu_user[idx] + cpu_idle[idx] + cpu_wait[idx];
+			printf(fmt, running, blocked, mem_swap, mem_free, mem_buff, mem_cache,
+				   (unsigned) (swap_bytes_in[idx]/inf.uptime),
+				   (unsigned) (swap_bytes_out[idx]/inf.uptime),
+				   (unsigned) (io_pages_in[idx]/inf.uptime),
+				   (unsigned) (io_pages_out[idx]/inf.uptime),
+				   (unsigned) (sys_irq[idx]/inf.uptime),
+				   (unsigned) (sys_ctxt[idx]/inf.uptime),
+				   (unsigned) (100*cpu_user[idx]/total_jif),
+				   (unsigned) (100*cpu_sys[idx]/total_jif),
+				   (unsigned) (100*cpu_idle[idx]/total_jif),
+				   (unsigned) (100*cpu_wait[idx]/total_jif));
+		}else{
+			total_jif = cpu_user[idx] - cpu_user[!idx] + cpu_idle[idx] - cpu_idle[!idx] + cpu_wait[idx] - cpu_wait[!idx];
+			printf(fmt, running, blocked, mem_swap, mem_free, mem_buff, mem_cache,
+				   (unsigned) ((swap_bytes_in[idx] - swap_bytes_in[!idx])/loop_delay),
+				   (unsigned) ((swap_bytes_out[idx] - swap_bytes_out[!idx])/loop_delay),
+				   (unsigned) ((io_pages_in[idx] - io_pages_in[!idx])/loop_delay),
+				   (unsigned) ((io_pages_out[idx] - io_pages_out[!idx])/loop_delay),
+				   (unsigned) ((sys_irq[idx] - sys_irq[!idx])/loop_delay),
+				   (unsigned) ((sys_ctxt[idx] - sys_ctxt[!idx])/loop_delay),
+				   (unsigned) (100*(cpu_user[idx] - cpu_user[!idx])/total_jif),
+				   (unsigned) (100*(cpu_sys[idx]  - cpu_sys[!idx]) /total_jif),
+				   (unsigned) (100*(cpu_idle[idx] - cpu_idle[!idx])/total_jif),
+				   (unsigned) (100*(cpu_wait[idx] - cpu_wait[!idx])/total_jif));
+		}
+
+		loop_num++;
+		if (loop_delay == 0 || (loop_max_num != 0 && loop_num >= loop_max_num))
+			break;
+		sleep(loop_delay);
+	}
+}