From 6d54da1b0f94e8e9149e3e44707c93375bb5900f Mon Sep 17 00:00:00 2001
From: bch <bch>
Date: Sat, 18 Feb 2017 21:06:47 +0000
Subject: [PATCH] load memory usage numbers (OpenBSD)

---
 get_mem.c | 110 +++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 93 insertions(+), 17 deletions(-)

diff --git a/get_mem.c b/get_mem.c
index c12d9a7..7412f71 100644
--- a/get_mem.c
+++ b/get_mem.c
@@ -1,5 +1,7 @@
-/*
- * get_mem.c
+/* 
+ * Adapted: get memory usage on OpenBSD
+ * Author: Christian Barthel <bch@vcs.onfire.org>
+ *
  * get memory usage, from get_load.c derived
  *
  * Author:  Hans-Helmut Buehmann 20. Jan. 1996
@@ -7,36 +9,110 @@
  * Modified for more recent kernels Helmut Geyer Oct. 1996
  */
 
+#include <sys/param.h>	/* DEV_BSIZE MAXCOMLEN PZERO */
+#include <sys/sysctl.h>
+#include <sys/swap.h>
+#include <sys/mount.h>
+#include <sys/proc.h>
 #include <X11/Xos.h>
 #include <X11/Intrinsic.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <unistd.h>
 #include "MemStripChart.h"
 
+static int pageshift = -1; 
+#define pagetok(size) ((size) << pageshift)
+#define LOG1024 10 
 
-void GetMemLoadPoint(w, closure, call_data)	/* Linux version */
-    Widget	w;		/* unused */
-    caddr_t	closure;	/* unused */
-    caddr_t	call_data;	/* pointer to (MemStripChartCallbackData) return value */
+static double allmem_kb = 0; 
+
+static void initPageShift(void)
 {
-    MemStripChartCallbackData ret;
-    /* meminfo();*/
+	int pagesize = getpagesize();
+	pageshift = 0;
+	while (pagesize > 1) {
+		pageshift++;
+		pagesize >>= 1;
+	}
+	pageshift -= LOG1024;
+}
 
-    /*et.code = (double)(kb_main_used - kb_main_buffers - kb_main_cached) / kb_main_total;
+static double getSwapFrac() 
+{
+	struct swapent *swdev;
+	int used, total, nswap, rnswap, i;
+
+	nswap = swapctl(SWAP_NSWAP, 0, 0);
+	if (nswap == 0)
+		return 0;
+
+	swdev = calloc(nswap, sizeof(*swdev));
+	if (swdev == NULL)
+		return 0;
+
+	rnswap = swapctl(SWAP_STATS, swdev, nswap);
+	if (rnswap == -1) {
+		free(swdev);
+		return 0;
+	}
+
+	/* if rnswap != nswap, then what? */
+
+	/* Total things up */
+	total = used = 0;
+	for (i = 0; i < nswap; i++) {
+		if (swdev[i].se_flags & SWF_ENABLE) {
+			used += (swdev[i].se_inuse / (1024 / DEV_BSIZE));
+			total += (swdev[i].se_nblks / (1024 / DEV_BSIZE));
+		}
+	}
+	free(swdev);
+	return (double)used/total;
+}
+
+void GetMemLoadPoint(Widget w, caddr_t closure, caddr_t call_data)	
+{
+	static int bcstats_mib[] = {CTL_VFS, VFS_GENERIC, VFS_BCACHESTAT};
+	static int uvmexp_mib[] = {CTL_VM, VM_UVMEXP};
+	MemStripChartCallbackData ret;
+	struct uvmexp uvmexp;
+	struct bcachestats bcstats;
+	size_t size; 
+	
+	if (pageshift < 0) 
+		initPageShift(); 
+
+	/*ret.code = (double)(kb_main_used - kb_main_buffers - kb_main_cached) / kb_main_total;
     ret.cached = (double)kb_main_cached / (double)kb_main_total;
     ret.buffer = (double)kb_main_buffers / (double)kb_main_total;
     ret.free = (double)kb_main_free / (double)kb_main_total;
     ret.swap = (double)kb_swap_used / (double)kb_main_total;
-
 		*/
 
-		printf("test?\n");
-    ret.code = 0.5;
-    ret.cached = 0.5;
-    ret.buffer = 0.5;
-    ret.free = 0.5;
-    ret.swap = 0.5;
+	size = sizeof(uvmexp);
+	if (sysctl(uvmexp_mib, 2, &uvmexp, &size, NULL, 0) < 0) {
+		warn("sysctl failed");
+		bzero(&uvmexp, sizeof(uvmexp));
+	}
+	size = sizeof(bcstats);
+	if (sysctl(bcstats_mib, 3, &bcstats, &size, NULL, 0) < 0) {
+		warn("sysctl failed");
+		bzero(&bcstats, sizeof(bcstats));
+	}
 
-    memcpy(call_data, &ret, sizeof(MemStripChartCallbackData));
+
+	allmem_kb = pagetok(uvmexp.npages); 
+	ret.cached = pagetok(bcstats.numbufpages) / allmem_kb;
+	ret.free = pagetok(uvmexp.free) / allmem_kb;
+	ret.buffer = 0;
+	ret.code = (1 - ret.cached - ret.free);
+	ret.swap = getSwapFrac();
+
+#ifdef DEBUG
+	printf("%lf  %lf %lf  %lf %lf\n", allmem_kb, ret.code, ret.cached, ret.free, ret.swap);
+#endif
+	
+	memcpy(call_data, &ret, sizeof(MemStripChartCallbackData));
 }