Add support for devnode symlinks

This implements creating symlinks for S: lines in umockdev device files.

Closes #90

Author: dlech

src/umockdev.vala

@@ -956,6 +956,7 @@ public class Testbed: GLib.Object {
         string cur_data = data;
         string? devnode_path = null;
         uint8[] devnode_contents = {};
+        string[] devnode_links = {};
 
         cur_data = this.record_parse_line(cur_data, out type, out key, out devpath);
         if (cur_data == null || type != 'P')
@@ -1018,7 +1019,10 @@ public class Testbed: GLib.Object {
                     break;
 
                 case 'S':
-                    /* TODO: ignored for now */
+                    /* collect symlinks */
+                    if (val == null)
+                        throw new UMockdev.Error.PARSE("invalid S: line in description of device %s", devpath);
+                    devnode_links += Path.build_filename(this.root_dir, "dev", val);
                     break;
 
                 default:
@@ -1043,9 +1047,16 @@ public class Testbed: GLib.Object {
             this.set_attribute_link (syspath, linkattrs[i], linkattrs[i+1]);
 
         /* create fake device node */
-        if (devnode_path != null)
+        if (devnode_path != null) {
             this.create_node_for_device(subsystem, devnode_path, devnode_contents, majmin);
 
+            /* create symlinks */
+            for (int i = 0; i < devnode_links.length; i++) {
+                assert (DirUtils.create_with_parents(Path.get_dirname(devnode_links[i]), 0755) == 0);
+                assert (FileUtils.symlink(devnode_path, devnode_links[i]) == 0);
+            }
+        }
+
         /* skip over multiple blank lines */
         while (cur_data[0] != '\0' && cur_data[0] == '\n')
             cur_data = cur_data.next_char();

tests/test-umockdev.c

@@ -1254,7 +1254,7 @@ static void
 t_testbed_add_from_string_dev_char(UMockdevTestbedFixture * fixture, gconstpointer data)
 {
     GError *error = NULL;
-    gchar *contents;
+    gchar *contents, *target;
     gsize length;
     GStatBuf st;
 
@@ -1270,6 +1270,20 @@ t_testbed_add_from_string_dev_char(UMockdevTestbedFixture * fixture, gconstpoint
     g_assert(S_ISCHR(st.st_mode));
     g_assert_cmpint(st.st_rdev, ==, makedev(1, 3));
 
+    /* N: with S: should create a symlink to DEVNAME */
+    g_assert(umockdev_testbed_add_from_string(fixture->testbed,
+					      "P: /devices/target\nN: target\nS: link\n"
+					      "E: SUBSYSTEM=foo\nE: DEVNAME=/dev/target\n"
+					      "A: dev=1:4\n", &error));
+    g_assert_no_error(error);
+
+    contents = g_file_read_link("/dev/link", &error);
+    g_assert_no_error(error);
+    target = g_build_filename(umockdev_testbed_get_root_dir(fixture->testbed), "dev/target", NULL);
+    g_assert_cmpstr(contents, ==, target);
+    g_free(target);
+    g_free(contents);
+
     /* N: another N without value whose name looks like hex */
     umockdev_testbed_add_from_string(fixture->testbed,
 				     "P: /devices/001\nN: bus/usb/001\n"