/*
* Hexchat Plugin API Bindings for Rust
* Copyright (C) 2018 Soni L.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
//! <!-- TODO (placeholder) -->
#[doc(hidden)]
pub extern crate libc;
mod internals;
use std::panic::catch_unwind;
use std::thread;
use std::ffi::{CString, CStr};
use std::str::FromStr;
const EMPTY_CSTRING_DATA: &[u8] = b"\0";
/// A hexchat plugin
pub trait Plugin {
fn init(&mut self, &mut PluginHandle) -> bool;
}
/// A handle for a hexchat plugin
pub struct PluginHandle {
ph: *mut internals::Ph,
filename: Option<CString>,
registered: bool,
fakehandle: *const internals::PluginGuiHandle,
}
impl PluginHandle {
pub fn register(&mut self, name: &str, desc: &str, ver: &str) {
unsafe {
let ph = &mut *self.ph;
if let Some(hexchat_plugingui_add) = ph.hexchat_plugingui_add {
let filename = self.filename.take().expect("Attempt to re-register a plugin");
let name = CString::new(name).unwrap();
let desc = CString::new(desc).unwrap();
let ver = CString::new(ver).unwrap();
self.fakehandle = hexchat_plugingui_add(self.ph, filename.as_ptr(), name.as_ptr(), desc.as_ptr(), ver.as_ptr(), ::std::ptr::null_mut());
}
self.registered = true;
}
}
}
#[doc(hidden)]
pub unsafe fn hexchat_plugin_init<T>(plugin_handle: *mut libc::c_void,
plugin_name: *mut *const libc::c_char,
plugin_desc: *mut *const libc::c_char,
plugin_version: *mut *const libc::c_char,
arg: *const libc::c_char) -> libc::c_int
where T: Plugin + Default {
if plugin_handle.is_null() {
// we can't really do anything here.
eprintln!("hexchat_plugin_init called with a null plugin_handle. This is an error!");
// TODO maybe call abort.
return 0;
}
let ph = &mut *(plugin_handle as *mut internals::Ph);
// clear the "userdata" field first thing - if the deinit function gets called (wrong hexchat
// version, other issues), we don't wanna try to drop the hexchat_dummy or hexchat_read_fd
// function as if it were a Box!
ph.userdata = ::std::ptr::null_mut();
// we set these to empty strings because rust strings aren't nul-terminated. which means we
// need to *allocate* nul-terminated strings for the real values, and hexchat has no way of
// freeing these.
// BUT before we set them, read the filename off plugin_name - we'll need it!
// (TODO figure out how to make this NOT break the plugins list)
let filename = CStr::from_ptr(*plugin_name).to_owned();
let empty_cstr = CStr::from_bytes_with_nul_unchecked(EMPTY_CSTRING_DATA).as_ptr();
*plugin_name = empty_cstr;
*plugin_desc = empty_cstr;
*plugin_version = empty_cstr;
// do some version checks for safety
if let Some(hexchat_get_info) = ph.hexchat_get_info {
let ver: *const libc::c_char = hexchat_get_info(ph, CStr::from_bytes_with_nul_unchecked(b"version\0").as_ptr());
let cstr = CStr::from_ptr(ver);
if let Ok(ver) = cstr.to_str() {
let mut iter = ver.split('.');
let a = iter.next().map(i32::from_str).and_then(Result::ok);
let b = iter.next().map(i32::from_str).and_then(Result::ok);
let c = iter.next().map(i32::from_str).and_then(Result::ok);
if !match a.unwrap_or(0) {
0 | 1 => false,
2 => match b.unwrap_or(0) {
// range patterns are a bit broken
0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 => false,
9 => match c.unwrap_or(0) {
0 | 1 | 2 | 3 | 4 | 5 => false,
6 =>
// min acceptable version = 2.9.6
true,
_ => true,
},
_ => true,
},
_ => true,
} {
// TODO print: "error loading plugin: hexchat too old"?
return 0;
}
} else {
return 0;
}
}
let r: thread::Result<Option<Box<_>>> = catch_unwind(|| {
let mut plug = T::default();
let mut pluginhandle = PluginHandle {
ph: plugin_handle as *mut _,
registered: false,
filename: Some(filename),
fakehandle: ::std::ptr::null(),
};
if plug.init(&mut pluginhandle) {
if pluginhandle.registered {
Some(Box::new((plug, pluginhandle.fakehandle)))
} else {
// TODO log: forgot to call register
None
}
} else {
None
}
});
if r.is_ok() {
if let Ok(Some(plug)) = r {
ph.userdata = Box::into_raw(plug) as *mut libc::c_void;
1
} else {
0
}
} else {
// TODO try to log panic?
0
}
}
#[doc(hidden)]
pub unsafe fn hexchat_plugin_deinit<T>(plugin_handle: *mut libc::c_void) where T: Plugin {
// plugin_handle should never be null, but just in case...
if !plugin_handle.is_null() {
let ph = &mut *(plugin_handle as *mut internals::Ph);
if !ph.userdata.is_null() {
//
let userdata = ph.userdata;
ph.userdata = ::std::ptr::null_mut();
// we use an explicit drop (instead of an implicit one) so this is less confusing/weird
// to read.
catch_unwind(|| {
let ph = &mut *(plugin_handle as *mut internals::Ph);
let (plug, fakehandle) = *Box::from_raw(userdata as *mut (T, *const internals::PluginGuiHandle));
if let Some(hexchat_plugingui_remove) = ph.hexchat_plugingui_remove {
hexchat_plugingui_remove(ph, fakehandle);
}
::std::mem::drop(plug); // suppress compiler warnings
}).ok();
}
} else {
eprintln!("hexchat_plugin_deinit called with a null plugin_handle. This is an error!");
}
}
/// Exports a hexchat plugin.
#[macro_export]
macro_rules! hexchat_plugin {
($t:ty) => {
#[no_mangle]
pub unsafe extern "C" fn hexchat_plugin_init(plugin_handle: *mut $crate::libc::c_void,
plugin_name: *mut *const $crate::libc::c_char,
plugin_desc: *mut *const $crate::libc::c_char,
plugin_version: *mut *const $crate::libc::c_char,
arg: *const $crate::libc::c_char) -> $crate::libc::c_int {
$crate::hexchat_plugin_init::<$t>(plugin_handle, plugin_name, plugin_desc, plugin_version, arg)
}
#[no_mangle]
pub unsafe extern "C" fn hexchat_plugin_deinit(plugin_handle: *mut $crate::libc::c_void) {
$crate::hexchat_plugin_deinit::<$t>(plugin_handle);
}
// unlike what the documentation states, there's no need to define hexchat_plugin_get_info.
// so we don't. it'd be impossible to make it work well with rust anyway.
};
}
