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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/// This macro is very similar to xpcom_macro, but works a bit differently:
///
/// When possible, it returns errors via the callback rather than via the return
/// value.
///
/// It implicitly adds the callback argument of type: nsIBitsNewRequestCallback
///
/// It needs an action type, to be specified before the rust name, in square
/// brackets.
///
/// The rustic implementation that the xpcom method calls is expected to return
/// the type: Result<_, BitsTaskError>. If this value is Ok, it will be ignored.
/// If the value is Err, it will be returned via the callback passed.
///
/// Usage like this:
///
/// ```ignore
/// nsIBits_method!(
/// [ActionType]
/// rust_method => XpcomMethod(
/// foo: *const nsACString,
/// bar: *const nsIBar,
/// baz: bool,
/// [optional] qux: *const nsIQux,
/// )
/// );
/// ```
///
/// Results in the macro generating a method like:
///
/// ```ignore
/// unsafe fn XpcomMethod(
/// &self,
/// foo: *const nsACString,
/// bar: *const nsIBar,
/// baz: bool,
/// qux: *const nsIQux,
/// callback: *const nsIBitsNewRequestCallback,
/// ) -> nsresult {
/// let callback: &nsIBitsNewRequestCallback = match xpcom::Ensure::ensure(callback) {
/// Ok(val) => val,
/// Err(result) => return result,
/// };
/// let foo = match xpcom::Ensure::ensure(foo) {
/// Ok(val) => val,
/// Err(_) => {
/// dispatch_pretask_interface_error(BitsTaskError::new(ErrorType::NullArgument, ActionType.into(), ErrorStage::Pretask), callback);
/// return NS_OK;
/// }
/// };
/// let bar = match xpcom::Ensure::ensure(bar) {
/// Ok(val) => val,
/// Err(_) => {
/// dispatch_pretask_interface_error(BitsTaskError::new(ErrorType::NullArgument, ActionType.into(), ErrorStage::Pretask), callback);
/// return NS_OK;
/// }
/// };
/// let baz = match xpcom::Ensure::ensure(baz) {
/// Ok(val) => val,
/// Err(_) => {
/// dispatch_pretask_interface_error(BitsTaskError::new(ErrorType::NullArgument, ActionType.into(), ErrorStage::Pretask), callback);
/// return NS_OK;
/// }
/// };
/// let qux = match xpcom::Ensure::ensure(qux) {
/// Ok(val) => Some(val),
/// Err(_) => None,
/// };
///
/// if let Err(error) = self.rust_method(foo, bar, baz, qux, callback) {
/// dispatch_pretask_interface_error(error, callback);
/// }
///
/// NS_OK
/// }
/// ```
///
/// Which expects a Rustic implementation method like:
///
/// ```ignore
/// fn rust_method(
/// &self,
/// foo: &nsACString,
/// bar: &nsIBar,
/// baz: bool,
/// qux: Option<&nsIQux>,
/// callback: &nsIBitsNewRequestCallback,
/// ) -> Result<(), BitsTaskError> {
/// do_something()
/// }
/// ```
#[macro_export]
macro_rules! nsIBits_method {
// The internal rule @ensure_param converts raw pointer arguments to
// references, calling dispatch_pretask_interface_error and returning if the
// argument is null.
// If, however, the type is optional, the reference will also be wrapped
// in an option and null pointers will be converted to None.
(@ensure_param [optional] $name:ident, $action:expr, $callback:ident) => {
let $name = match Ensure::ensure($name) {
Ok(val) => Some(val),
Err(_) => None,
};
};
(@ensure_param $name:ident, $action:expr, $callback:ident) => {
let $name = match Ensure::ensure($name) {
Ok(val) => val,
Err(_) => {
dispatch_pretask_interface_error(BitsTaskError::new(NullArgument, $action.into(), Pretask), $callback);
return NS_OK;
}
};
};
([$action:expr] $rust_name:ident => $xpcom_name:ident($($([$param_required:ident])* $param_name:ident: $param_type:ty $(,)*)*)) => {
#[allow(non_snake_case)]
unsafe fn $xpcom_name(&self, $($param_name: $param_type, )* callback: *const nsIBitsNewRequestCallback) -> nsresult {
use xpcom::Ensure;
use nserror::NS_OK;
// When no params are passed, the imports below will not be used, so silence the
// warning
#[allow(unused_imports)]
use bits_interface::{
dispatch_callback::dispatch_pretask_interface_error,
error::{BitsTaskError, ErrorStage::Pretask, ErrorType::NullArgument},
};
let callback: &nsIBitsNewRequestCallback = match Ensure::ensure(callback) {
Ok(val) => val,
Err(result) => return result,
};
$(nsIBits_method!(@ensure_param $([$param_required])* $param_name, $action, callback);)*
if let Err(error) = self.$rust_name($($param_name, )* callback) {
dispatch_pretask_interface_error(error, callback);
}
NS_OK
}
};
}
/*
* Same as above, but expects a nsIBitsCallback as its callback.
*/
#[macro_export]
macro_rules! nsIBitsRequest_method {
// The internal rule @ensure_param converts raw pointer arguments to
// references, calling dispatch_pretask_interface_error and returning if the
// argument is null.
// If, however, the type is optional, the reference will also be wrapped
// in an option and null pointers will be converted to None.
(@ensure_param [optional] $name:ident, $action:expr, $callback:ident) => {
let $name = match Ensure::ensure($name) {
Ok(val) => Some(val),
Err(_) => None,
};
};
(@ensure_param $name:ident, $action:expr, $callback:ident) => {
let $name = match Ensure::ensure($name) {
Ok(val) => val,
Err(_) => {
dispatch_pretask_request_error(BitsTaskError::new(NullArgument, $action.into(), Pretask), $callback);
return NS_OK;
}
};
};
([$action:expr] $rust_name:ident => $xpcom_name:ident($($([$param_required:ident])* $param_name:ident: $param_type:ty $(,)*)*)) => {
#[allow(non_snake_case)]
unsafe fn $xpcom_name(&self, $($param_name: $param_type, )* callback: *const nsIBitsCallback) -> nsresult {
use xpcom::Ensure;
use nserror::NS_OK;
// When no params are passed, the imports below will not be used, so silence the
// warning
#[allow(unused_imports)]
use bits_interface::{
dispatch_callback::dispatch_pretask_request_error,
error::{BitsTaskError, ErrorStage::Pretask, ErrorType::NullArgument},
};
let callback: &nsIBitsCallback = match Ensure::ensure(callback) {
Ok(val) => val,
Err(result) => return result,
};
$(nsIBitsRequest_method!(@ensure_param $([$param_required])* $param_name, $action, callback);)*
if let Err(error) = self.$rust_name($($param_name, )* callback) {
dispatch_pretask_request_error(error, callback);
}
NS_OK
}
};
}