[Libguestfs] [PATCH] Rust bindings: Implement Event features
Hiroyuki Katsura
hiroyuki.katsura.0513 at gmail.com
Tue Jul 30 05:51:37 UTC 2019
This patch includes:
- Event callback handlers
- Tests related to events(410-430)
---
generator/rust.ml | 38 ++++++-
rust/src/base.rs | 24 +++--
rust/src/error.rs | 8 +-
rust/src/event.rs | 158 ++++++++++++++++++++++++++++
rust/src/lib.rs | 2 +
rust/tests/040_create_multiple.rs | 2 +-
rust/tests/410_close_event.rs | 38 +++++++
rust/tests/420_log_messages.rs | 60 +++++++++++
rust/tests/430_progress_messages.rs | 61 +++++++++++
9 files changed, 381 insertions(+), 10 deletions(-)
create mode 100644 rust/src/event.rs
create mode 100644 rust/tests/410_close_event.rs
create mode 100644 rust/tests/420_log_messages.rs
create mode 100644 rust/tests/430_progress_messages.rs
diff --git a/generator/rust.ml b/generator/rust.ml
index a1735602c..1f5cefa62 100644
--- a/generator/rust.ml
+++ b/generator/rust.ml
@@ -72,6 +72,42 @@ extern \"C\" {
}
";
+ (* event enum *)
+ pr "\n";
+ pr "pub enum Event {\n";
+ List.iter (
+ fun (name, _) ->
+ pr " %s,\n" (snake2caml name)
+ ) events;
+ pr "}\n\n";
+
+ pr "impl Event {\n";
+ pr " pub fn to_u64(&self) -> u64 {\n";
+ pr " match self {\n";
+ List.iter (
+ fun (name, i) ->
+ pr " Event::%s => %d,\n" (snake2caml name) i
+ ) events;
+ pr " }\n";
+ pr " }\n";
+ pr " pub fn from_bitmask(bitmask: u64) -> Option<Event> {\n";
+ pr " match bitmask {\n";
+ List.iter (
+ fun (name, i) ->
+ pr " %d => Some(Event::%s),\n" i (snake2caml name)
+ ) events;
+ pr " _ => None,\n";
+ pr " }\n";
+ pr " }\n";
+ pr "}\n\n";
+
+ pr "pub const EVENT_ALL: [Event; %d] = [\n" (List.length events);
+ List.iter (
+ fun (name, _) ->
+ pr " Event::%s,\n" (snake2caml name)
+ ) events;
+ pr "];\n";
+
List.iter (
fun { s_camel_name = name; s_name = c_name; s_cols = cols } ->
pr "\n";
@@ -356,7 +392,7 @@ extern \"C\" {
pr "}\n";
- pr "impl Handle {\n";
+ pr "impl<'a> Handle<'a> {\n";
List.iter (
fun ({ name = name; shortdesc = shortdesc; longdesc = longdesc;
style = (ret, args, optargs) } as f) ->
diff --git a/rust/src/base.rs b/rust/src/base.rs
index 02ad33535..0c6a3bdba 100644
--- a/rust/src/base.rs
+++ b/rust/src/base.rs
@@ -17,6 +17,10 @@
*/
use crate::error;
+use crate::event;
+use crate::guestfs;
+use std::collections;
+use std::sync;
#[allow(non_camel_case_types)]
#[repr(C)]
@@ -34,31 +38,37 @@ extern "C" {
const GUESTFS_CREATE_NO_ENVIRONMENT: i64 = 1;
const GUESTFS_CREATE_NO_CLOSE_ON_EXIT: i64 = 2;
-pub struct Handle {
+pub struct Handle<'a> {
pub(crate) g: *mut guestfs_h,
+ pub(crate) callbacks: collections::HashMap<
+ event::EventHandle,
+ sync::Arc<Fn(guestfs::Event, event::EventHandle, &[u8], &[u64]) + 'a>,
+ >,
}
-impl Handle {
- pub fn create() -> Result<Handle, error::Error> {
+impl<'a> Handle<'a> {
+ pub fn create() -> Result<Handle<'a>, error::Error> {
let g = unsafe { guestfs_create() };
if g.is_null() {
Err(error::Error::Create)
} else {
- Ok(Handle { g })
+ let callbacks = collections::HashMap::new();
+ Ok(Handle { g, callbacks })
}
}
- pub fn create_flags(flags: CreateFlags) -> Result<Handle, error::Error> {
+ pub fn create_flags(flags: CreateFlags) -> Result<Handle<'a>, error::Error> {
let g = unsafe { guestfs_create_flags(flags.to_libc_int()) };
if g.is_null() {
Err(error::Error::Create)
} else {
- Ok(Handle { g })
+ let callbacks = collections::HashMap::new();
+ Ok(Handle { g, callbacks })
}
}
}
-impl Drop for Handle {
+impl<'a> Drop for Handle<'a> {
fn drop(&mut self) {
unsafe { guestfs_close(self.g) }
}
diff --git a/rust/src/error.rs b/rust/src/error.rs
index 705ee1735..ce444e199 100644
--- a/rust/src/error.rs
+++ b/rust/src/error.rs
@@ -20,6 +20,7 @@ use crate::base;
use crate::utils;
use std::convert;
use std::ffi;
+use std::io;
use std::os::raw::{c_char, c_int};
use std::str;
@@ -41,6 +42,7 @@ pub enum Error {
API(APIError),
IllegalString(ffi::NulError),
Utf8Error(str::Utf8Error),
+ UnixError(io::Error, &'static str),
Create,
}
@@ -56,7 +58,11 @@ impl convert::From<str::Utf8Error> for Error {
}
}
-impl base::Handle {
+pub(crate) fn unix_error(operation: &'static str) -> Error {
+ Error::UnixError(io::Error::last_os_error(), operation)
+}
+
+impl<'a> base::Handle<'a> {
pub(crate) fn get_error_from_handle(&self, operation: &'static str) -> Error {
let c_msg = unsafe { guestfs_last_error(self.g) };
let message = unsafe { utils::char_ptr_to_string(c_msg).unwrap() };
diff --git a/rust/src/event.rs b/rust/src/event.rs
new file mode 100644
index 000000000..942feec69
--- /dev/null
+++ b/rust/src/event.rs
@@ -0,0 +1,158 @@
+/* libguestfs Rust bindings
+ * Copyright (C) 2019 Hiroyuki Katsura <hiroyuki.katsura.0513 at gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+use crate::base;
+use crate::error;
+use crate::guestfs;
+use std::ffi;
+use std::os::raw::{c_char, c_void};
+use std::slice;
+use std::sync;
+
+type GuestfsEventCallback = extern "C" fn(
+ *const base::guestfs_h,
+ *const c_void,
+ u64,
+ i32,
+ i32,
+ *const i8,
+ usize,
+ *const u64,
+ usize,
+);
+
+#[link(name = "guestfs")]
+extern "C" {
+ fn guestfs_set_event_callback(
+ g: *const base::guestfs_h,
+ cb: GuestfsEventCallback,
+ event_bitmask: u64,
+ flags: i32,
+ opaque: *const c_void,
+ ) -> i32;
+ fn guestfs_delete_event_callback(g: *const base::guestfs_h, eh: i32);
+ fn guestfs_event_to_string(bitmask: u64) -> *const c_char;
+ fn free(buf: *const c_void);
+}
+
+#[derive(Hash, PartialEq, Eq)]
+pub struct EventHandle {
+ eh: i32,
+}
+
+pub type Callback = FnMut(guestfs::Event, EventHandle, &[i8], &[u64]);
+
+fn events_to_bitmask(v: &[guestfs::Event]) -> u64 {
+ let mut r = 0u64;
+ for x in v.iter() {
+ r |= x.to_u64();
+ }
+ r
+}
+
+pub fn event_to_string(events: &[guestfs::Event]) -> Result<String, error::Error> {
+ let bitmask = events_to_bitmask(events);
+
+ let r = unsafe { guestfs_event_to_string(bitmask) };
+ if r.is_null() {
+ Err(error::unix_error("event_to_string"))
+ } else {
+ let s = unsafe { ffi::CStr::from_ptr(r) };
+ let s = s.to_str()?.to_string();
+ unsafe { free(r as *const c_void) };
+ Ok(s)
+ }
+}
+
+/* -- Why Not Box<Callback> but Arc<Callback> (in struct base::Handle)? --
+ * Assume that there are more than threads. While callback is running,
+ * if a thread frees the handle, automatically the buffer is freed if Box<Callback>
+ * is used. Therefore Arc<Callback> is used.
+ */
+
+impl<'a> base::Handle<'a> {
+ pub fn set_event_callback<C: 'a>(
+ &mut self,
+ callback: C,
+ events: &[guestfs::Event],
+ ) -> Result<EventHandle, error::Error>
+ where
+ C: Fn(guestfs::Event, EventHandle, &[u8], &[u64]),
+ {
+ extern "C" fn trampoline<C>(
+ _g: *const base::guestfs_h,
+ opaque: *const c_void,
+ event: u64,
+ event_handle: i32,
+ _flags: i32,
+ buf: *const c_char,
+ buf_len: usize,
+ array: *const u64,
+ array_len: usize,
+ ) where
+ C: Fn(guestfs::Event, EventHandle, &[u8], &[u64]),
+ {
+ // trampoline function
+ // c.f. https://s3.amazonaws.com/temp.michaelfbryan.com/callbacks/index.html
+
+ let event = match guestfs::Event::from_bitmask(event) {
+ Some(x) => x,
+ None => panic!("Failed to parse bitmask: {}", event),
+ };
+ let eh = EventHandle { eh: event_handle };
+ let buf = unsafe { slice::from_raw_parts(buf as *const u8, buf_len) };
+ let array = unsafe { slice::from_raw_parts(array, array_len) };
+
+ let callback_ptr = unsafe { &*(opaque as *const sync::Arc<C>) };
+ let callback = sync::Arc::clone(&callback_ptr);
+ callback(event, eh, buf, array)
+ }
+ let callback = sync::Arc::<C>::new(callback);
+ let event_bitmask = events_to_bitmask(events);
+
+ let eh = {
+ // Weak::into_raw is nightly.
+ // In order to make sure that callback is freed when handle is freed,
+ // lifetime is explicitly declared.
+ let ptr: &'a sync::Arc<C> = Box::leak(Box::new(callback.clone()));
+ unsafe {
+ guestfs_set_event_callback(
+ self.g,
+ trampoline::<C>,
+ event_bitmask,
+ 0,
+ ptr as *const sync::Arc<C> as *const c_void,
+ )
+ }
+ };
+ if eh == -1 {
+ return Err(self.get_error_from_handle("set_event_callback"));
+ }
+ self.callbacks.insert(EventHandle { eh }, callback);
+
+ Ok(EventHandle { eh })
+ }
+
+ pub fn delete_event_callback(&mut self, eh: EventHandle) -> Result<(), error::Error> {
+ unsafe {
+ guestfs_delete_event_callback(self.g, eh.eh);
+ }
+ self.callbacks.remove(&eh);
+ Ok(())
+ }
+}
diff --git a/rust/src/lib.rs b/rust/src/lib.rs
index cc41a99f8..81adef2a3 100644
--- a/rust/src/lib.rs
+++ b/rust/src/lib.rs
@@ -18,9 +18,11 @@
mod base;
mod error;
+mod event;
mod guestfs;
mod utils;
pub use crate::base::*;
pub use crate::error::*;
+pub use crate::event::*;
pub use crate::guestfs::*;
diff --git a/rust/tests/040_create_multiple.rs b/rust/tests/040_create_multiple.rs
index cc93554a3..970c988af 100644
--- a/rust/tests/040_create_multiple.rs
+++ b/rust/tests/040_create_multiple.rs
@@ -18,7 +18,7 @@
extern crate guestfs;
-fn create() -> guestfs::Handle {
+fn create<'a>() -> guestfs::Handle<'a> {
match guestfs::Handle::create() {
Ok(g) => g,
Err(e) => panic!("fail: {:?}", e),
diff --git a/rust/tests/410_close_event.rs b/rust/tests/410_close_event.rs
new file mode 100644
index 000000000..308471098
--- /dev/null
+++ b/rust/tests/410_close_event.rs
@@ -0,0 +1,38 @@
+/* libguestfs Rust bindings
+ * Copyright (C) 2019 Hiroyuki Katsura <hiroyuki.katsura.0513 at gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+extern crate guestfs;
+
+use std::sync::{Arc, Mutex};
+
+#[test]
+fn close_event() {
+ let close_invoked = Arc::new(Mutex::new(0));
+ {
+ let mut g = guestfs::Handle::create().expect("create");
+ g.set_event_callback(
+ |_, _, _, _| {
+ let mut data = (&close_invoked).lock().unwrap();
+ *data += 1;
+ },
+ &[guestfs::Event::Close],
+ )
+ .unwrap();
+ }
+ assert_eq!(*((&close_invoked).lock().unwrap()), 1);
+}
diff --git a/rust/tests/420_log_messages.rs b/rust/tests/420_log_messages.rs
new file mode 100644
index 000000000..1e9627ca7
--- /dev/null
+++ b/rust/tests/420_log_messages.rs
@@ -0,0 +1,60 @@
+/* libguestfs Rust bindings
+ * Copyright (C) 2019 Hiroyuki Katsura <hiroyuki.katsura.0513 at gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+extern crate guestfs;
+
+use std::str;
+use std::sync::{Arc, Mutex};
+
+#[test]
+fn log_messages() {
+ let close_invoked = Arc::new(Mutex::new(0));
+ {
+ let mut g = guestfs::Handle::create().expect("create");
+ g.set_event_callback(
+ |ev, _, buf, array| {
+ let mut data = (&close_invoked).lock().unwrap();
+ *data += 1;
+
+ let event = guestfs::event_to_string(&[ev]).unwrap();
+
+ let buf = str::from_utf8(buf).unwrap();
+ let array = array
+ .into_iter()
+ .map(|x| format!("{}", x))
+ .collect::<Vec<String>>()
+ .join(",");
+
+ eprintln!("event logged: event={} buf={} array={}", event, buf, array)
+ },
+ &[
+ guestfs::Event::Appliance,
+ guestfs::Event::Library,
+ guestfs::Event::Warning,
+ guestfs::Event::Trace,
+ ],
+ )
+ .unwrap();
+
+ g.set_trace(true).unwrap();
+ g.set_verbose(true).unwrap();
+ g.add_drive_ro("/dev/null").unwrap();
+ g.set_autosync(true).unwrap();
+ }
+ assert!(*((&close_invoked).lock().unwrap()) > 0);
+}
diff --git a/rust/tests/430_progress_messages.rs b/rust/tests/430_progress_messages.rs
new file mode 100644
index 000000000..a1d33aff7
--- /dev/null
+++ b/rust/tests/430_progress_messages.rs
@@ -0,0 +1,61 @@
+/* libguestfs Rust bindings
+ * Copyright (C) 2019 Hiroyuki Katsura <hiroyuki.katsura.0513 at gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+extern crate guestfs;
+
+use std::default::Default;
+use std::sync::{Arc, Mutex};
+
+#[test]
+fn progress_messages() {
+ let callback_invoked = Arc::new(Mutex::new(0));
+ {
+ let mut g = guestfs::Handle::create().expect("create");
+ g.add_drive("/dev/null", Default::default()).unwrap();
+ g.launch().unwrap();
+
+ let eh = g
+ .set_event_callback(
+ |_, _, _, _| {
+ let mut data = (&callback_invoked).lock().unwrap();
+ *data += 1;
+ },
+ &[guestfs::Event::Progress],
+ )
+ .unwrap();
+ assert_eq!("ok", g.debug("progress", &["5"]).unwrap());
+ assert!(*(&callback_invoked).lock().unwrap() > 0);
+
+ *(&callback_invoked).lock().unwrap() = 0;
+ g.delete_event_callback(eh).unwrap();
+ assert_eq!("ok", g.debug("progress", &["5"]).unwrap());
+ assert_eq!(*(&callback_invoked).lock().unwrap(), 0);
+
+ g.set_event_callback(
+ |_, _, _, _| {
+ let mut data = (&callback_invoked).lock().unwrap();
+ *data += 1;
+ },
+ &[guestfs::Event::Progress],
+ )
+ .unwrap();
+ assert_eq!("ok", g.debug("progress", &["5"]).unwrap());
+ assert!(*(&callback_invoked).lock().unwrap() > 0);
+ }
+ assert!(*(&callback_invoked).lock().unwrap() > 0);
+}
--
2.20.1 (Apple Git-117)
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