Re: [Libguestfs] [PATCH 1/2] gobject: Allow RConstOptString to return an error

RConstOptString cannot return an error in the C api. This makes it a special case for the GObject api, as all other return types have a corresponding GError **err argument to return an error. This change removes this special case, and includes the possibility of an error return in the API. An error is indicated by setting *err to a non-NULL value. This change is in preparation for adding a close api. An attempt to call any api, even RConstOptString, on a closed handle must return an error. --- generator/generator_gobject.ml | 29 +++++++++++------------------ 1 files changed, 11 insertions(+), 18 deletions(-) diff --git a/generator/generator_gobject.ml b/generator/generator_gobject.ml index 4779f23..abc9062 100644 --- a/generator/generator_gobject.ml +++ b/generator/generator_gobject.ml @@ -37,10 +37,6 @@ let camel_of_name flags name = a ^ String.uppercase (Str.first_chars b 1) ^ Str.string_after b 1 ) "" (Str.split (regexp "_") name) -let returns_error = function - | RConstOptString _ -> false - | _ -> true - let generate_gobject_proto name ?(single_line = true) (ret, args, optargs) flags = let spacer = if single_line then " " else "\n" in @@ -109,7 +105,7 @@ let generate_gobject_proto name ?(single_line = true) | _ -> ()); if List.exists (function Cancellable -> true | _ -> false) flags then pr ", GCancellable *cancellable"; - if returns_error ret then pr ", GError **err"; + pr ", GError **err"; pr ")" let generate_gobject_header_static () = @@ -602,7 +598,7 @@ let generate_gobject_c_methods () = let doc = String.concat "\n * " doc in let camel_name = camel_of_name flags name in let is_RBufferOut = match ret with RBufferOut _ -> true | _ -> false in - let error_return = match ret with + let gobject_error_return = match ret with | RErr -> "FALSE" | RInt _ | RInt64 _ | RBool _ -> @@ -688,7 +684,7 @@ let generate_gobject_c_methods () = if cancellable then ( pr " /* Check we haven't already been cancelled */\n"; pr " if (g_cancellable_set_error_if_cancelled (cancellable, err))\n"; - pr " return %s;\n\n" error_return; + pr " return %s;\n\n" gobject_error_return; ); pr " guestfs_h *g = session->priv->g;\n"; @@ -780,19 +776,16 @@ let generate_gobject_c_methods () = (* Check return, throw error if necessary, marshall return value *) - if returns_error ret then ( + (match errcode_of_ret ret with + | `CannotReturnError -> () + | _ -> pr " if (ret == %s) {\n" - (match ret with - | RErr | RInt _ | RInt64 _ | RBool _ -> - "-1" - | RConstString _ | RString _ | RStringList _ | RHashtable _ - | RBufferOut _ | RStruct _ | RStructList _ -> - "NULL" - | RConstOptString _ -> - assert false; - ); + (match errcode_of_ret ret with + | `CannotReturnError -> assert false + | `ErrorIsMinusOne -> "-1" + | `ErrorIsNULL -> "NULL"); pr " g_set_error_literal(err, GUESTFS_ERROR, 0, guestfs_last_error(g));\n"; - pr " return %s;\n" error_return; + pr " return %s;\n" gobject_error_return; pr " }\n"; ); pr "\n";