diff options
| -rw-r--r-- | src/lib.rs | 114 |
1 files changed, 93 insertions, 21 deletions
diff --git a/src/lib.rs b/src/lib.rs index 93ba6d6..a700c96 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -131,7 +131,7 @@ * hexchat_list_int, hexchat_list_time, hexchat_list_free * -[x] hexchat_hook_command * -[ ] hexchat_hook_fd - * -[#] hexchat_hook_print (implemented through _attrs) + * -[x] hexchat_hook_print * -[x] hexchat_hook_print_attrs * -[#] hexchat_hook_server (implemented through _attrs) * -[x] hexchat_hook_server_attrs @@ -170,6 +170,7 @@ use std::ops; use std::panic::catch_unwind; use std::ptr; use std::rc::Rc; +use std::rc::Weak as RcWeak; use std::str::FromStr; use std::thread; use std::time::{SystemTime, UNIX_EPOCH, Duration}; @@ -231,6 +232,7 @@ pub trait Plugin { /// ``` pub struct PluginHandle { ph: *mut internals::Ph, + skip_pri_ck: bool, // Used for registration info: PluginInfo, } @@ -352,11 +354,10 @@ pub struct TimerHookHandle { } /// A context. -// We don't want this Copy + Clone, as we may want to implement a context invalidation system -// at some point (rather than relying on the hexchat allocator not to allocate a new context where -// a context was free'd). +#[derive(Clone)] pub struct Context { - ctx: *const internals::HexchatContext, + ctx: RcWeak<*const internals::HexchatContext>, // may be null + closure: Rc<Cell<Option<PrintHookHandle>>>, } // #[derive(Debug)] // doesn't work @@ -536,7 +537,7 @@ impl<'a> ops::Deref for WordEol<'a> { impl PluginHandle { fn new(ph: *mut internals::Ph, info: PluginInfo) -> PluginHandle { PluginHandle { - ph, info + ph, info, skip_pri_ck: false, } } @@ -651,18 +652,35 @@ impl PluginHandle { /// Note: The returned context may be invalid. Use [`set_context`] to check. /// /// [`set_context`]: #method.set_context + // This needs to be fixed by hexchat. I cannot make the value become null when it's invalid + // without invoking UB. This is because I can't set_context to null. pub fn get_context(&mut self) -> Context { - unsafe { - Context { ctx: ((*self.ph).hexchat_get_context)(self.ph) } - } + let ctxp = unsafe { ((*self.ph).hexchat_get_context)(self.ph) }; + unsafe { wrap_context(self, ctxp) } + // let ctxp = std::panic::AssertUnwindSafe(Rc::new(unsafe { ((*self.ph).hexchat_get_context)(self.ph) })); + // let weak_ctxp = Rc::downgrade(&ctxp); // calling the Closure should drop the Context (sort of) + // let closure: Rc<Cell<Option<PrintHookHandle>>> = Rc::new(Cell::new(None)); + // let hook = std::panic::AssertUnwindSafe(Rc::downgrade(&closure)); // dropping the Context should drop the Closure + // self.skip_pri_ck = true; + // closure.set(Some(self.hook_print("Close Context", move |ph, _| { + // let _ = &ctxp; + // let _: Option<PrintHookHandle> = hook.upgrade().unwrap().replace(None); + // EAT_NONE + // }, libc::c_int::min_value()))); + // self.skip_pri_ck = false; + // Context { ctx: weak_ctxp, closure } } /// Sets the current context. /// /// Returns `true` if the context is valid, `false` otherwise. pub fn set_context(&mut self, ctx: &Context) -> bool { - unsafe { - ((*self.ph).hexchat_set_context)(self.ph, ctx.ctx) != 0 + if let Some(ctx) = ctx.ctx.upgrade() { + unsafe { + ((*self.ph).hexchat_set_context)(self.ph, *ctx) != 0 + } + } else { + false } } @@ -811,8 +829,43 @@ impl PluginHandle { /// ] /// } /// ``` - pub fn hook_print<F>(&mut self, name: &str, cb: F, pri: i32) -> PrintHookHandle where F: Fn(&mut PluginHandle, Word) -> Eat + 'static + ::std::panic::RefUnwindSafe { - self.hook_print_attrs(name, move |ph, w, _| cb(ph, w), pri) + pub fn hook_print<F>(&mut self, name: &str, cb: F, mut pri: i32) -> PrintHookHandle where F: Fn(&mut PluginHandle, Word) -> Eat + 'static + ::std::panic::RefUnwindSafe { + // hmm, is there any way to avoid this code duplication? + // hook_print is special because dummy prints (keypresses, Close Context) are handled + // through here, but never through hook_print_attrs. :/ + unsafe extern "C" fn callback(word: *const *const libc::c_char, ud: *mut libc::c_void) -> libc::c_int { + // hook may unhook itself. + // however, we don't wanna free it until it has returned. + let f: Rc<PrintHookUd> = rc_clone_from_raw(ud as *const PrintHookUd); + let ph = f.1; + match catch_unwind(move || { + let word = Word::new(word); + (f.0)(&mut PluginHandle::new(f.1, f.2), word, EventAttrs::new()).do_eat as libc::c_int + }) { + Result::Ok(v @ _) => v, + Result::Err(e @ _) => { + // if it's a &str or String, just print it + if let Some(estr) = e.downcast_ref::<&str>() { + hexchat_print_str(ph, estr, false); + } else if let Some(estring) = e.downcast_ref::<String>() { + hexchat_print_str(ph, &estring, false); + } + 0 // EAT_NONE + } + } + } + if name == "Close Context" && (pri as libc::c_int == libc::c_int::min_value()) && !self.skip_pri_ck { + self.print("Warning: Attempted to hook Close Context with priority INT_MIN. Adjusting to INT_MIN+1."); + pri = (libc::c_int::min_value() + 1) as i32; + } + let b: Rc<PrintHookUd> = Rc::new((Box::new(move |ph, w, _| cb(ph, w)), self.ph, self.info)); + let name = CString::new(name).unwrap(); + let bp = Rc::into_raw(b); + unsafe { + let res = ((*self.ph).hexchat_hook_print)(self.ph, name.as_ptr(), pri as libc::c_int, callback, bp as *mut _); + assert!(!res.is_null()); + PrintHookHandle { ph: self.ph, hh: res, _f: PhantomData } + } } /// Sets a print hook, with attributes. pub fn hook_print_attrs<F>(&mut self, name: &str, cb: F, pri: i32) -> PrintHookHandle where F: Fn(&mut PluginHandle, Word, EventAttrs) -> Eat + 'static + ::std::panic::RefUnwindSafe { @@ -958,13 +1011,13 @@ impl PluginHandle { #[allow(unused_mut)] let mut list = ((*ph).hexchat_list_get)(ph, cstr(b"channels\0")); // hexchat does this thing where it puts a context in a list_str. - // this is the proper way to do this + // this *is* the proper way to do this if ((*ph).hexchat_list_next)(ph, list) != 0 { // if this panics we may leak some memory. it's not a big deal tho, as it indicates // a bug in hexchat-plugin.rs. let ctx = ((*ph).hexchat_list_str)(ph, list, cstr(b"context\0")) as *const internals::HexchatContext; ((*ph).hexchat_list_free)(ph, list); - Some(Context { ctx }) + Some(wrap_context(self, ctx)) } else { ((*ph).hexchat_list_free)(ph, list); None @@ -1029,7 +1082,7 @@ impl<'a> EnsureValidContext<'a> { if ctx.is_null() { None } else { - Some(Context { ctx }) + Some(unsafe { wrap_context(self.ph, ctx) }) } } @@ -1182,6 +1235,26 @@ unsafe fn rc_clone_from_raw<T>(ptr: *const T) -> Rc<T> { rc } +/// Converts a **valid** context pointer into a Context (Rust-managed) struct. +/// +/// # Safety +/// +/// This function doesn't validate the context. +unsafe fn wrap_context(ph: &mut PluginHandle, ctx: *const internals::HexchatContext) -> Context { + let ctxp = std::panic::AssertUnwindSafe(Rc::new(ctx)); + let weak_ctxp = Rc::downgrade(&ctxp); // calling the Closure should drop the Context (sort of) + let closure: Rc<Cell<Option<PrintHookHandle>>> = Rc::new(Cell::new(None)); + let hook = std::panic::AssertUnwindSafe(Rc::downgrade(&closure)); // dropping the Context should drop the Closure + ph.skip_pri_ck = true; + closure.set(Some(ph.hook_print("Close Context", move |ph, _| { + let _ = &ctxp; + let _: Option<PrintHookHandle> = hook.upgrade().unwrap().replace(None); + EAT_NONE + }, libc::c_int::min_value()))); + ph.skip_pri_ck = false; + Context { ctx: weak_ctxp, closure } +} + /// Prints an &str to hexchat, trying to avoid allocations. /// /// # Safety @@ -1384,10 +1457,7 @@ pub unsafe fn hexchat_plugin_init<T>(plugin_handle: *mut libc::c_void, }; let r: thread::Result<Option<Box<_>>> = { catch_unwind(move || { - let mut pluginhandle = PluginHandle { - ph: ph, - info: pluginfo, - }; + let mut pluginhandle = PluginHandle::new(ph, pluginfo); let plug = T::default(); if plug.init(&mut pluginhandle, if !arg.is_null() { Some(CStr::from_ptr(arg).to_str().expect("arg not valid utf-8 - broken hexchat")) } else { None }) { if !(pluginfo.name.is_null() || pluginfo.desc.is_null() || pluginfo.vers.is_null()) { @@ -1415,6 +1485,8 @@ pub unsafe fn hexchat_plugin_init<T>(plugin_handle: *mut libc::c_void, r @ _ => { // if the initialization fails, deinit doesn't get called, so we need to clean up // ourselves. + + // TODO might leak pluginfo on panic? if let Err(_) = r { // TODO try to log panic? @@ -1439,7 +1511,7 @@ pub unsafe fn hexchat_plugin_deinit<T>(plugin_handle: *mut libc::c_void) -> libc safe_to_unload = if catch_unwind(move || { let userdata = *pop_userdata(ph); **ausinfo = Some(userdata.pluginfo); - userdata.plug.deinit(&mut PluginHandle { ph, info: userdata.pluginfo }); + userdata.plug.deinit(&mut PluginHandle::new(ph, userdata.pluginfo)); }).is_ok() { 1 } else { 0 }; } if let Some(mut info) = info { |