glib/error.rs
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402
// Take a look at the license at the top of the repository in the LICENSE file.
// rustdoc-stripper-ignore-next
//! `Error` binding and helper trait.
use std::{borrow::Cow, convert::Infallible, error, ffi::CStr, fmt, str};
use crate::{ffi, translate::*, Quark};
wrapper! {
// rustdoc-stripper-ignore-next
/// A generic error capable of representing various error domains (types).
// rustdoc-stripper-ignore-next-stop
/// The `GError` structure contains information about
/// an error that has occurred.
// rustdoc-stripper-ignore-next-stop
/// The `GError` structure contains information about
/// an error that has occurred.
#[derive(PartialEq, Eq, PartialOrd, Ord, Hash)]
#[doc(alias = "GError")]
pub struct Error(Boxed<ffi::GError>);
match fn {
copy => |ptr| ffi::g_error_copy(ptr),
free => |ptr| ffi::g_error_free(ptr),
type_ => || ffi::g_error_get_type(),
}
}
unsafe impl Send for Error {}
unsafe impl Sync for Error {}
impl Error {
// rustdoc-stripper-ignore-next
/// Creates an error with supplied error enum variant and message.
// rustdoc-stripper-ignore-next-stop
/// Creates a new #GError with the given @domain and @code,
/// and a message formatted with @format.
/// ## `domain`
/// error domain
/// ## `code`
/// error code
/// ## `format`
/// printf()-style format for error message
///
/// # Returns
///
/// a new #GError
// rustdoc-stripper-ignore-next-stop
/// Creates a new #GError with the given @domain and @code,
/// and a message formatted with @format.
/// ## `domain`
/// error domain
/// ## `code`
/// error code
/// ## `format`
/// printf()-style format for error message
///
/// # Returns
///
/// a new #GError
#[doc(alias = "g_error_new_literal")]
#[doc(alias = "g_error_new")]
pub fn new<T: ErrorDomain>(error: T, message: &str) -> Error {
unsafe {
from_glib_full(ffi::g_error_new_literal(
T::domain().into_glib(),
error.code(),
message.to_glib_none().0,
))
}
}
// rustdoc-stripper-ignore-next
/// Checks if the error domain matches `T`.
pub fn is<T: ErrorDomain>(&self) -> bool {
self.inner.domain == T::domain().into_glib()
}
// rustdoc-stripper-ignore-next
/// Returns the error domain quark
pub fn domain(&self) -> Quark {
unsafe { from_glib(self.inner.domain) }
}
// rustdoc-stripper-ignore-next
/// Checks if the error matches the specified domain and error code.
// rustdoc-stripper-ignore-next-stop
/// Returns [`true`] if @self matches @domain and @code, [`false`]
/// otherwise. In particular, when @self is [`None`], [`false`] will
/// be returned.
///
/// If @domain contains a `FAILED` (or otherwise generic) error code,
/// you should generally not check for it explicitly, but should
/// instead treat any not-explicitly-recognized error code as being
/// equivalent to the `FAILED` code. This way, if the domain is
/// extended in the future to provide a more specific error code for
/// a certain case, your code will still work.
/// ## `domain`
/// an error domain
/// ## `code`
/// an error code
///
/// # Returns
///
/// whether @self has @domain and @code
// rustdoc-stripper-ignore-next-stop
/// Returns [`true`] if @self matches @domain and @code, [`false`]
/// otherwise. In particular, when @self is [`None`], [`false`] will
/// be returned.
///
/// If @domain contains a `FAILED` (or otherwise generic) error code,
/// you should generally not check for it explicitly, but should
/// instead treat any not-explicitly-recognized error code as being
/// equivalent to the `FAILED` code. This way, if the domain is
/// extended in the future to provide a more specific error code for
/// a certain case, your code will still work.
/// ## `domain`
/// an error domain
/// ## `code`
/// an error code
///
/// # Returns
///
/// whether @self has @domain and @code
#[doc(alias = "g_error_matches")]
pub fn matches<T: ErrorDomain>(&self, err: T) -> bool {
self.is::<T>() && self.inner.code == err.code()
}
// rustdoc-stripper-ignore-next
/// Tries to convert to a specific error enum.
///
/// Returns `Some` if the error belongs to the enum's error domain and
/// `None` otherwise.
///
/// # Examples
///
/// ```ignore
/// if let Some(file_error) = error.kind::<FileError>() {
/// match file_error {
/// FileError::Exist => ...
/// FileError::Isdir => ...
/// ...
/// }
/// }
/// ```
pub fn kind<T: ErrorDomain>(&self) -> Option<T> {
if self.is::<T>() {
T::from(self.inner.code)
} else {
None
}
}
// rustdoc-stripper-ignore-next
/// Returns the error message
///
/// Most of the time you can simply print the error since it implements the `Display`
/// trait, but you can use this method if you need to have the message as a `&str`.
pub fn message(&self) -> &str {
unsafe {
let bytes = CStr::from_ptr(self.inner.message).to_bytes();
str::from_utf8(bytes)
.unwrap_or_else(|err| str::from_utf8(&bytes[..err.valid_up_to()]).unwrap())
}
}
}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.write_str(self.message())
}
}
impl fmt::Debug for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("Error")
.field("domain", unsafe {
&crate::Quark::from_glib(self.inner.domain)
})
.field("code", &self.inner.code)
.field("message", &self.message())
.finish()
}
}
impl error::Error for Error {}
impl From<Infallible> for Error {
fn from(e: Infallible) -> Self {
match e {}
}
}
// rustdoc-stripper-ignore-next
/// `GLib` error domain.
///
/// This trait is implemented by error enums that represent error domains (types).
pub trait ErrorDomain: Copy {
// rustdoc-stripper-ignore-next
/// Returns the quark identifying the error domain.
///
/// As returned from `g_some_error_quark`.
fn domain() -> Quark;
// rustdoc-stripper-ignore-next
/// Gets the integer representation of the variant.
fn code(self) -> i32;
// rustdoc-stripper-ignore-next
/// Tries to convert an integer code to an enum variant.
///
/// By convention, the `Failed` variant, if present, is a catch-all,
/// i.e. any unrecognized codes map to it.
fn from(code: i32) -> Option<Self>
where
Self: Sized;
}
// rustdoc-stripper-ignore-next
/// Generic error used for functions that fail without any further information
#[macro_export]
macro_rules! bool_error(
($($msg:tt)*) => {{
match ::std::format_args!($($msg)*) {
formatted => {
if let Some(s) = formatted.as_str() {
$crate::BoolError::new(
s,
file!(),
$crate::function_name!(),
line!()
)
} else {
$crate::BoolError::new(
formatted.to_string(),
file!(),
$crate::function_name!(),
line!(),
)
}
}
}
}};
);
#[macro_export]
macro_rules! result_from_gboolean(
($ffi_bool:expr, $($msg:tt)*) => {{
match ::std::format_args!($($msg)*) {
formatted => {
if let Some(s) = formatted.as_str() {
$crate::BoolError::from_glib(
$ffi_bool,
s,
file!(),
$crate::function_name!(),
line!(),
)
} else {
$crate::BoolError::from_glib(
$ffi_bool,
formatted.to_string(),
file!(),
$crate::function_name!(),
line!(),
)
}
}
}
}};
);
#[derive(Debug, Clone)]
pub struct BoolError {
pub message: Cow<'static, str>,
#[doc(hidden)]
pub filename: &'static str,
#[doc(hidden)]
pub function: &'static str,
#[doc(hidden)]
pub line: u32,
}
impl BoolError {
pub fn new(
message: impl Into<Cow<'static, str>>,
filename: &'static str,
function: &'static str,
line: u32,
) -> Self {
Self {
message: message.into(),
filename,
function,
line,
}
}
pub fn from_glib(
b: ffi::gboolean,
message: impl Into<Cow<'static, str>>,
filename: &'static str,
function: &'static str,
line: u32,
) -> Result<(), Self> {
match b {
ffi::GFALSE => Err(BoolError::new(message, filename, function, line)),
_ => Ok(()),
}
}
}
impl fmt::Display for BoolError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.write_str(&self.message)
}
}
impl error::Error for BoolError {}
#[cfg(test)]
mod tests {
use std::ffi::CString;
use super::*;
use crate::prelude::*;
#[test]
fn test_error_matches() {
let e = Error::new(crate::FileError::Failed, "Failed");
assert!(e.matches(crate::FileError::Failed));
assert!(!e.matches(crate::FileError::Again));
assert!(!e.matches(crate::KeyFileError::NotFound));
}
#[test]
fn test_error_kind() {
let e = Error::new(crate::FileError::Failed, "Failed");
assert_eq!(e.kind::<crate::FileError>(), Some(crate::FileError::Failed));
assert_eq!(e.kind::<crate::KeyFileError>(), None);
}
#[test]
fn test_into_raw() {
unsafe {
let e: *mut ffi::GError =
Error::new(crate::FileError::Failed, "Failed").into_glib_ptr();
assert_eq!((*e).domain, ffi::g_file_error_quark());
assert_eq!((*e).code, ffi::G_FILE_ERROR_FAILED);
assert_eq!(
CStr::from_ptr((*e).message),
CString::new("Failed").unwrap().as_c_str()
);
ffi::g_error_free(e);
}
}
#[test]
fn test_bool_error() {
let from_static_msg = bool_error!("Static message");
assert_eq!(from_static_msg.to_string(), "Static message");
let from_dynamic_msg = bool_error!("{} message", "Dynamic");
assert_eq!(from_dynamic_msg.to_string(), "Dynamic message");
let false_static_res = result_from_gboolean!(ffi::GFALSE, "Static message");
assert!(false_static_res.is_err());
let static_err = false_static_res.err().unwrap();
assert_eq!(static_err.to_string(), "Static message");
let true_static_res = result_from_gboolean!(ffi::GTRUE, "Static message");
assert!(true_static_res.is_ok());
let false_dynamic_res = result_from_gboolean!(ffi::GFALSE, "{} message", "Dynamic");
assert!(false_dynamic_res.is_err());
let dynamic_err = false_dynamic_res.err().unwrap();
assert_eq!(dynamic_err.to_string(), "Dynamic message");
let true_dynamic_res = result_from_gboolean!(ffi::GTRUE, "{} message", "Dynamic");
assert!(true_dynamic_res.is_ok());
}
#[test]
fn test_value() {
let e1 = Error::new(crate::FileError::Failed, "Failed");
// This creates a copy ...
let v = e1.to_value();
// ... so we have to get the raw pointer from inside the value to check for equality.
let ptr = unsafe {
crate::gobject_ffi::g_value_get_boxed(v.to_glib_none().0) as *const ffi::GError
};
let e2 = v.get::<&Error>().unwrap();
assert_eq!(ptr, e2.to_glib_none().0);
}
}