utils: more flexible reading of /proc/sys/net

- changes nm_utils_get_proc_sys_net_value() to allow all values, not just 0,1
- adds nm_utils_get_proc_sys_net_value_with_bounds() for limiting valid values

src/NetworkManagerUtils.c

@@ -848,7 +848,7 @@ nm_utils_do_sysctl (const char *path, const char *value)
 gboolean
 nm_utils_get_proc_sys_net_value (const char *path,
                                  const char *iface,
-                                 guint32 *out_value)
+                                 gint32 *out_value)
 {
 	GError *error = NULL;
 	char *contents = NULL;
@@ -864,8 +864,8 @@ nm_utils_get_proc_sys_net_value (const char *path,
 	} else {
 		errno = 0;
 		tmp = strtol (contents, NULL, 10);
-		if ((errno == 0) && (tmp == 0 || tmp == 1)) {
+		if (errno == 0) {
-			*out_value = (guint32) tmp;
+			*out_value = (gint32) tmp;
 			success = TRUE;
 		}
 		g_free (contents);
@@ -874,6 +874,28 @@ nm_utils_get_proc_sys_net_value (const char *path,
 	return success;
 }
 
+gboolean
+nm_utils_get_proc_sys_net_value_with_bounds (const char *path,
+                                             const char *iface,
+                                             gint32 *out_value,
+                                             gint32 valid_min,
+                                             gint32 valid_max)
+{
+	gboolean result;
+	gint32 val;
+
+	result = nm_utils_get_proc_sys_net_value (path, iface, &val);
+
+	if (result) {
+		if (val >= valid_min && val <= valid_max)
+			*out_value = val;
+		else
+			result = FALSE;
+	}
+
+	return result;
+}
+
 static char *
 get_new_connection_name (const GSList *existing,
                          const char *format,

src/NetworkManagerUtils.h

@@ -15,7 +15,7 @@
  * with this program; if not, write to the Free Software Foundation, Inc.,
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  *
- * Copyright (C) 2004 - 2010 Red Hat, Inc.
+ * Copyright (C) 2004 - 2011 Red Hat, Inc.
  * Copyright (C) 2005 - 2008 Novell, Inc.
  */
 
@@ -83,7 +83,13 @@ gboolean nm_utils_do_sysctl (const char *path, const char *value);
 
 gboolean nm_utils_get_proc_sys_net_value (const char *path,
                                           const char *iface,
-                                          guint32 *out_value);
+                                          gint32 *out_value);
+
+gboolean nm_utils_get_proc_sys_net_value_with_bounds (const char *path,
+                                                      const char *iface,
+                                                      gint32 *out_value,
+                                                      gint32 valid_min,
+                                                      gint32 valid_max);
 
 void nm_utils_complete_generic (NMConnection *connection,
                                 const char *ctype,

src/ip6-manager/nm-ip6-manager.c

@@ -91,7 +91,7 @@ typedef struct {
 
 	char *disable_ip6_path;
 	gboolean disable_ip6_save_valid;
-	guint32 disable_ip6_save;
+	gint32 disable_ip6_save;
 
 	guint finish_addrconf_id;
 	guint config_changed_id;
@@ -185,9 +185,10 @@ nm_ip6_device_new (NMIP6Manager *manager, int ifindex)
 	device->disable_ip6_path = g_strdup_printf ("/proc/sys/net/ipv6/conf/%s/disable_ipv6",
 	                                            device->iface);
 	g_assert (device->disable_ip6_path);
-	device->disable_ip6_save_valid = nm_utils_get_proc_sys_net_value (device->disable_ip6_path,
+	device->disable_ip6_save_valid = nm_utils_get_proc_sys_net_value_with_bounds (device->disable_ip6_path,
-	                                                                  device->iface,
+	                                                                              device->iface,
-	                                                                  &device->disable_ip6_save);
+	                                                                              &device->disable_ip6_save,
+	                                                                              0, 1);
 
 	return device;
 

src/nm-device.c

@@ -204,7 +204,7 @@ typedef struct {
 	NMIP6Config *  ac_ip6_config;
 
 	char *         ip6_accept_ra_path;
-	guint32        ip6_accept_ra_save;
+	gint32         ip6_accept_ra_save;
 
 	NMDHCPClient *  dhcp6_client;
 	guint32         dhcp6_mode;
@@ -281,9 +281,10 @@ update_accept_ra_save (NMDevice *self)
 
 	/* Grab the original value of "accept_ra" so we can restore it when NM exits */
 	priv->ip6_accept_ra_path = new_path;
-	if (!nm_utils_get_proc_sys_net_value (priv->ip6_accept_ra_path,
+	if (!nm_utils_get_proc_sys_net_value_with_bounds (priv->ip6_accept_ra_path,
-	                                      ip_iface,
+	                                                  ip_iface,
-	                                      &priv->ip6_accept_ra_save)) {
+	                                                  &priv->ip6_accept_ra_save,
+	                                                  0, 1)) {
 		g_free (priv->ip6_accept_ra_path);
 		priv->ip6_accept_ra_path = NULL;
 	}