ibus: fall back from unreadable machine id

tests/ibus_test.c

@@ -24,6 +24,49 @@ struct Ibusfix
 	int	pumpactive;
 };
 
+void
+ibus_machine_id_fallback(struct ct *t)
+{
+	char root[] = "/tmp/strans-machine-id.XXXXXX";
+	char primary[128], fallback[128], got[64];
+	char *path[2];
+	FILE *fp;
+	int madeprimary, madefallback;
+
+	madeprimary = 0;
+	madefallback = 0;
+	if(!CT_CHECK(t, mkdtemp(root) != nil))
+		return;
+	if(!CT_CHECK(t, snprintf(primary, sizeof primary, "%s/primary", root)
+	   < (int)sizeof primary) ||
+	   !CT_CHECK(t, snprintf(fallback, sizeof fallback, "%s/fallback", root)
+	   < (int)sizeof fallback))
+		goto cleanup;
+	if(!CT_CHECK(t, mkdir(primary, 0700) == 0))
+		goto cleanup;
+	madeprimary = 1;
+	fp = fopen(fallback, "w");
+	if(!CT_CHECK(t, fp != nil))
+		goto cleanup;
+	madefallback = 1;
+	if(!CT_CHECK(t, fputs("fallback-machine-id\n", fp) >= 0)){
+		fclose(fp);
+		goto cleanup;
+	}
+	if(!CT_CHECK(t, fclose(fp) == 0))
+		goto cleanup;
+	path[0] = primary;
+	path[1] = fallback;
+	machineidfiles(got, sizeof got, path, nelem(path));
+	CT_EQ_STR(t, "fallback-machine-id", got);
+cleanup:
+	if(madefallback)
+		CT_CHECK(t, unlink(fallback) == 0);
+	if(madeprimary)
+		CT_CHECK(t, rmdir(primary) == 0);
+	CT_CHECK(t, rmdir(root) == 0);
+}
+
 static void
 enginepump(void *arg)
 {