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use session::Session;
use metadata::creader::PluginMetadataReader;
use plugin::registry::Registry;
use std::mem;
use std::os;
use std::dynamic_lib::DynamicLibrary;
use syntax::ast;
use syntax::attr;
use syntax::visit;
use syntax::visit::Visitor;
use syntax::ext::expand::ExportedMacros;
use syntax::attr::AttrMetaMethods;
pub struct PluginMetadata {
pub macros: Vec<String>,
pub lib: Option<Path>,
pub registrar_symbol: Option<String>,
}
pub type PluginRegistrarFun =
fn(&mut Registry);
pub struct Plugins {
pub macros: Vec<ExportedMacros>,
pub registrars: Vec<PluginRegistrarFun>,
}
struct PluginLoader<'a> {
sess: &'a Session,
reader: PluginMetadataReader<'a>,
plugins: Plugins,
}
impl<'a> PluginLoader<'a> {
fn new(sess: &'a Session) -> PluginLoader<'a> {
PluginLoader {
sess: sess,
reader: PluginMetadataReader::new(sess),
plugins: Plugins {
macros: vec!(),
registrars: vec!(),
},
}
}
}
pub fn load_plugins(sess: &Session, krate: &ast::Crate,
addl_plugins: Option<Plugins>) -> Plugins {
let mut loader = PluginLoader::new(sess);
visit::walk_crate(&mut loader, krate);
let mut plugins = loader.plugins;
match addl_plugins {
Some(addl_plugins) => {
let Plugins { macros: addl_macros, registrars: addl_registrars } = addl_plugins;
plugins.macros.extend(addl_macros.into_iter());
plugins.registrars.extend(addl_registrars.into_iter());
}
None => ()
}
return plugins;
}
impl<'a, 'v> Visitor<'v> for PluginLoader<'a> {
fn visit_view_item(&mut self, vi: &ast::ViewItem) {
match vi.node {
ast::ViewItemExternCrate(name, _, _) => {
let mut plugin_phase = false;
for attr in vi.attrs.iter().filter(|a| a.check_name("phase")) {
let phases = attr.meta_item_list().unwrap_or(&[]);
if attr::contains_name(phases, "plugin") {
plugin_phase = true;
}
if attr::contains_name(phases, "syntax") {
plugin_phase = true;
self.sess.span_warn(attr.span,
"phase(syntax) is a deprecated synonym for phase(plugin)");
}
}
if !plugin_phase { return; }
let PluginMetadata { macros, lib, registrar_symbol } =
self.reader.read_plugin_metadata(vi);
self.plugins.macros.push(ExportedMacros {
crate_name: name,
macros: macros,
});
match (lib, registrar_symbol) {
(Some(lib), Some(symbol))
=> self.dylink_registrar(vi, lib, symbol),
_ => (),
}
}
_ => (),
}
}
fn visit_mac(&mut self, _: &ast::Mac) {
}
}
impl<'a> PluginLoader<'a> {
fn dylink_registrar(&mut self, vi: &ast::ViewItem, path: Path, symbol: String) {
let path = os::make_absolute(&path).unwrap();
let lib = match DynamicLibrary::open(Some(&path)) {
Ok(lib) => lib,
Err(err) => self.sess.span_fatal(vi.span, err[])
};
unsafe {
let registrar =
match lib.symbol(symbol[]) {
Ok(registrar) => {
mem::transmute::<*mut u8,PluginRegistrarFun>(registrar)
}
Err(err) => self.sess.span_fatal(vi.span, err[])
};
self.plugins.registrars.push(registrar);
mem::forget(lib);
}
}
}