New has_sysfs function to avoid stating over and over '/sys' on each

2006-07-27  Benoît Dejean  <benoit@placenet.org>

        * glibtop_private.c: (has_sysfs):
        * glibtop_private.h:
        * netload.c: (glibtop_get_netload_s):
        * open.c: (set_linux_version):

        New has_sysfs function to avoid stating
        over and over '/sys' on each netload call.

sysdeps/linux/ChangeLog

@@ -1,3 +1,13 @@
+2006-07-27  Benoît Dejean  <benoit@placenet.org>
+
+	* glibtop_private.c: (has_sysfs):
+	* glibtop_private.h:
+	* netload.c: (glibtop_get_netload_s):
+	* open.c: (set_linux_version):
+
+	New has_sysfs function to avoid stating
+	over and over '/sys' on each netload call.
+
 2006-04-02  Benoît Dejean  <benoit@placenet.org>
 
 	* msg_limits.c: (glibtop_get_msg_limits_s):

sysdeps/linux/glibtop_private.c

@@ -163,3 +163,18 @@ check_cpu_line(glibtop *server, const char *line, unsigned i)
 	return g_str_has_prefix(line, start);
 }
 
+
+
+gboolean
+has_sysfs(void)
+{
+	static gboolean init;
+	static gboolean sysfs;
+
+	if (G_UNLIKELY(!init)) {
+		sysfs = g_file_test("/sys", G_FILE_TEST_IS_DIR);
+		init = TRUE;
+	}
+
+	return sysfs;
+}

sysdeps/linux/glibtop_private.h

@@ -142,6 +142,10 @@ check_cpu_line_warn(glibtop *server, const char *line, unsigned i)
 }
 
 
+gboolean
+has_sysfs(void) G_GNUC_INTERNAL G_GNUC_CONST;
+
+
 G_END_DECLS
 
 #endif /* __LINUX__GLIBTOP_PRIVATE_H__ */

sysdeps/linux/netload.c

@@ -541,7 +541,7 @@ glibtop_get_netload_s (glibtop *server, glibtop_netload *buf,
 	linux_2_0_stats(server, buf, interface);
     }
     else if (server->os_version_code > LINUX_VERSION_CODE(2, 6, 0)
-	     && g_file_test("/sys", G_FILE_TEST_IS_DIR)) {
+	     && has_sysfs()) {
 	linux_2_6_stats(server, buf, interface);
     }
     else {

sysdeps/linux/open.c

@@ -50,7 +50,7 @@ static void set_linux_version(glibtop *server)
 			       uts.release, x, y, z, LINUX_VERSION_CODE(x,y,z));
 
 	if (LINUX_VERSION_CODE(x, y, z) >= LINUX_VERSION_CODE(2, 6, 0)
-	    && !g_file_test("/sys", G_FILE_TEST_IS_DIR))
+	    && !has_sysfs())
 		glibtop_warn_r(server,
 			       "You're running a 2.6 kernel without /sys."
 			       "You should mount it.");