qmemman: make meminfo-writer a C program

common/Makefile

@@ -0,0 +1,7 @@
+CC=gcc
+CFLAGS=-Wall -g
+all:	meminfo-writer
+meminfo-writer: meminfo-writer.o
+	$(CC) -g -o meminfo-writer meminfo-writer.o -lxenstore
+clean:
+	rm -f meminfo-writer *.o *~

common/meminfo-writer

@@ -1,4 +0,0 @@
-#!/bin/sh
-while sleep 1 ; do
-	xenstore-write memory/meminfo "`cat /proc/meminfo`"
-done

common/meminfo-writer.c

@@ -0,0 +1,62 @@
+/*
+ * The Qubes OS Project, http://www.qubes-os.org
+ *
+ * Copyright (C) 2010  Rafal Wojtczuk  <rafal@invisiblethingslab.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ */
+#include <sys/types.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <xs.h>
+#include <syslog.h>
+int main()
+{
+	struct xs_handle *xs;
+	int fd, n;
+	char buf[4096];
+
+	openlog("meminfo-writer", LOG_CONS | LOG_PID, LOG_DAEMON);
+	xs = xs_domain_open();
+	if (!xs) {
+		syslog(LOG_DAEMON | LOG_ERR, "xs_domain_open");
+		exit(1);
+	}
+	for (;;) {
+		fd = open("/proc/meminfo", O_RDONLY);
+		if (fd < 0) {
+			syslog(LOG_DAEMON | LOG_ERR,
+			       "error opening /proc/meminfo ?");
+			exit(1);
+		}
+		n = read(fd, buf, sizeof(buf));
+		if (n <= 0) {
+			syslog(LOG_DAEMON | LOG_ERR,
+			       "error reading /proc/meminfo ?");
+			exit(1);
+		}
+		close(fd);
+		if (!xs_write(xs, XBT_NULL, "memory/meminfo", buf, n)) {
+			syslog(LOG_DAEMON | LOG_ERR,
+			       "error writing xenstore ?");
+			exit(1);
+		}
+		sleep(1);
+	}
+}

rpm_spec/core-appvm.spec

@@ -52,6 +52,7 @@ fi
 
 %build
 make clean all
+make -C ../common
 
 %install