client: Fix reading long values

While value has more than single MTU can carry long read procedure will
be triggered. In such cases offset need to bo considered while getting
value from storage.

Change-Id: Ide2d67c7562a83f317e699627a7c22ba058c47f8
Signed-off-by: Amit Purwar <amit.purwar@samsung.com>

diff --git a/client/gatt.c b/client/gatt.c
index 8c818d8..7a6035a 100755 (executable)
--- a/client/gatt.c
+++ b/client/gatt.c
@@ -1412,6 +1412,39 @@ static const GDBusPropertyTable chrc_properties[] = {
        { }
 };
 
+static int parse_offset(DBusMessageIter *iter, uint16_t *offset)
+{
+       DBusMessageIter dict;
+
+       if (dbus_message_iter_get_arg_type(iter) != DBUS_TYPE_ARRAY)
+               return -EINVAL;
+
+       dbus_message_iter_recurse(iter, &dict);
+
+       while (dbus_message_iter_get_arg_type(&dict) == DBUS_TYPE_DICT_ENTRY) {
+               const char *key;
+               DBusMessageIter value, entry;
+               int var;
+
+               dbus_message_iter_recurse(&dict, &entry);
+               dbus_message_iter_get_basic(&entry, &key);
+
+               dbus_message_iter_next(&entry);
+               dbus_message_iter_recurse(&entry, &value);
+
+               var = dbus_message_iter_get_arg_type(&value);
+               if (strcasecmp(key, "offset") == 0) {
+                       if (var != DBUS_TYPE_UINT16)
+                               return -EINVAL;
+                       dbus_message_iter_get_basic(&value, offset);
+               }
+
+               dbus_message_iter_next(&dict);
+       }
+
+       return 0;
+}
+
 static DBusMessage *read_value(DBusMessage *msg, uint8_t *value,
                                                uint16_t value_len)
 {
@@ -1433,8 +1466,14 @@ static DBusMessage *chrc_read_value(DBusConnection *conn, DBusMessage *msg,
                                                        void *user_data)
 {
        struct chrc *chrc = user_data;
+       DBusMessageIter iter;
+       uint16_t offset = 0;
+
+       dbus_message_iter_init(msg, &iter);
+
+       parse_offset(&iter, &offset);
 
-       return read_value(msg, chrc->value, chrc->value_len);
+       return read_value(msg, &chrc->value[offset], chrc->value_len - offset);
 }
 
 static int parse_value_arg(DBusMessageIter *iter, uint8_t **value, int *len)
@@ -1785,8 +1824,14 @@ static DBusMessage *desc_read_value(DBusConnection *conn, DBusMessage *msg,
                                                        void *user_data)
 {
        struct desc *desc = user_data;
+       DBusMessageIter iter;
+       uint16_t offset = 0;
+
+       dbus_message_iter_init(msg, &iter);
+
+       parse_offset(&iter, &offset);
 
-       return read_value(msg, desc->value, desc->value_len);
+       return read_value(msg, &desc->value[offset], desc->value_len - offset);
 }
 
 static DBusMessage *desc_write_value(DBusConnection *conn, DBusMessage *msg,