SBUS: Return / if an object path getter returns NULL

Reviewed-by: Stef Walter <stefw@redhat.com>
Reviewed-by: Pavel Březina <pbrezina@redhat.com>

5 files changed, 29 insertions, 1 deletions

diff --git a/src/sbus/sbus_codegen b/src/sbus/sbus_codegen
index b671e939f..6507753f2 100755
--- a/src/sbus/sbus_codegen
+++ b/src/sbus/sbus_codegen
@@ -320,6 +320,8 @@ def source_getter_invoker(prop):
     out("")
     if prop.type == "s":
         out("    out_val = prop_val == NULL ? \"\" : prop_val;")
+    elif prop.type == "o":
+        out("    out_val = prop_val == NULL ? \"/\" : prop_val;")
     else:
         out("    out_val = prop_val;")
     if prop.is_array:
diff --git a/src/tests/sbus_codegen_tests.c b/src/tests/sbus_codegen_tests.c
index e92c5f784..c7da414fe 100644
--- a/src/tests/sbus_codegen_tests.c
+++ b/src/tests/sbus_codegen_tests.c
@@ -441,6 +441,13 @@ void pilot_get_null_string_handler(struct sbus_request *dbus_req,
     *string_val = NULL;
 }
 
+void pilot_get_null_path_handler(struct sbus_request *dbus_req,
+                                 void *instance_data,
+                                 const char **path_val)
+{
+    *path_val = NULL;
+}
+
 #define array_getter_body(in, out, outlen) do {     \
     ck_assert(dbus_req != NULL);                    \
     ck_assert(out != NULL);                         \
@@ -548,6 +555,7 @@ struct test_pilot pilot_iface = {
     .test_pilot_get_string = pilot_get_string_handler,
     .test_pilot_get_object_path = pilot_get_objpath_handler,
     .test_pilot_get_null_string = pilot_get_null_string_handler,
+    .test_pilot_get_null_path = pilot_get_null_path_handler,
 
     .test_pilot_get_byte_array = pilot_get_byte_array_handler,
     .test_pilot_get_int16_array = pilot_get_int16_array_handler,
@@ -857,6 +865,12 @@ START_TEST(test_get_basic_types)
     call_get(client, "/test/leela", test_pilot_meta.name, "null_string",
              DBUS_TYPE_STRING, &string_val);
     ck_assert_str_eq(string_val, "");
+
+    /* If a string getter returns NULL, the caller should receive "/" */
+    call_get(client, "/test/leela", test_pilot_meta.name, "null_path",
+             DBUS_TYPE_OBJECT_PATH, &path_val);
+    ck_assert_str_eq(path_val, "/");
+
 }
 END_TEST
 
diff --git a/src/tests/sbus_codegen_tests.xml b/src/tests/sbus_codegen_tests.xml
index c44f38305..90e274254 100755
--- a/src/tests/sbus_codegen_tests.xml
+++ b/src/tests/sbus_codegen_tests.xml
@@ -122,6 +122,7 @@
 
         <!-- Special properties to test error codes -->
         <property name="null_string" type="s" access="read"/>
+        <property name="null_path" type="o" access="read"/>
 
         <!-- Property arrays with every type of basic argument except boolean
              which we can't do (yet) -->
diff --git a/src/tests/sbus_codegen_tests_generated.c b/src/tests/sbus_codegen_tests_generated.c
index 211ad8967..70302daff 100644
--- a/src/tests/sbus_codegen_tests_generated.c
+++ b/src/tests/sbus_codegen_tests_generated.c
@@ -372,6 +372,15 @@ const struct sbus_property_meta test_pilot__properties[] = {
         NULL, /* no invoker */
     },
     {
+        "null_path", /* name */
+        "o", /* type */
+        SBUS_PROPERTY_READABLE,
+        offsetof(struct test_pilot, test_pilot_get_null_path),
+        invoke_get_o,
+        0, /* not writable */
+        NULL, /* no invoker */
+    },
+    {
         "byte_array", /* name */
         "ay", /* type */
         SBUS_PROPERTY_READABLE,
@@ -716,7 +725,7 @@ static int invoke_get_o(struct sbus_request *dbus_req, void *function_ptr)
 
     (handler)(dbus_req, dbus_req->intf->instance_data, &prop_val);
 
-    out_val = prop_val;
+    out_val = prop_val == NULL ? "/" : prop_val;
     return sbus_request_return_as_variant(dbus_req, DBUS_TYPE_OBJECT_PATH, &out_val);
 }
 
diff --git a/src/tests/sbus_codegen_tests_generated.h b/src/tests/sbus_codegen_tests_generated.h
index 7dc817edf..e6fb10c5e 100644
--- a/src/tests/sbus_codegen_tests_generated.h
+++ b/src/tests/sbus_codegen_tests_generated.h
@@ -36,6 +36,7 @@
 #define TEST_PILOT_STRING "string"
 #define TEST_PILOT_OBJECT_PATH "object_path"
 #define TEST_PILOT_NULL_STRING "null_string"
+#define TEST_PILOT_NULL_PATH "null_path"
 #define TEST_PILOT_BYTE_ARRAY "byte_array"
 #define TEST_PILOT_INT16_ARRAY "int16_array"
 #define TEST_PILOT_UINT16_ARRAY "uint16_array"
@@ -98,6 +99,7 @@ struct test_pilot {
     void (*test_pilot_get_string)(struct sbus_request *, void *data, const char * *);
     void (*test_pilot_get_object_path)(struct sbus_request *, void *data, const char * *);
     void (*test_pilot_get_null_string)(struct sbus_request *, void *data, const char * *);
+    void (*test_pilot_get_null_path)(struct sbus_request *, void *data, const char * *);
     void (*test_pilot_get_byte_array)(struct sbus_request *, void *data, uint8_t * *, int *);
     void (*test_pilot_get_int16_array)(struct sbus_request *, void *data, int16_t * *, int *);
     void (*test_pilot_get_uint16_array)(struct sbus_request *, void *data, uint16_t * *, int *);