Auto merge of #77 - sfackler:error, r=pcwalton

Add CFError support

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core-foundation-sys/src/array.rs

@@ -34,7 +34,7 @@ pub struct CFArrayCallBacks {
 }
 
 #[repr(C)]
-struct __CFArray(c_void);
+pub struct __CFArray(c_void);
 
 pub type CFArrayRef = *const __CFArray;
 

core-foundation-sys/src/bundle.rs

@@ -13,7 +13,7 @@ use base::CFTypeID;
 use string::CFStringRef;
 
 #[repr(C)]
-struct __CFBundle(c_void);
+pub struct __CFBundle(c_void);
 
 pub type CFBundleRef = *const __CFBundle;
 

core-foundation-sys/src/data.rs

@@ -3,7 +3,7 @@ use libc::c_void;
 use base::{CFAllocatorRef, CFTypeID, CFIndex};
 
 #[repr(C)]
-struct __CFData(c_void);
+pub struct __CFData(c_void);
 
 pub type CFDataRef = *const __CFData;
 

core-foundation-sys/src/dictionary.rs

@@ -42,7 +42,7 @@ pub struct CFDictionaryValueCallBacks {
 }
 
 #[repr(C)]
-struct __CFDictionary(c_void);
+pub struct __CFDictionary(c_void);
 
 pub type CFDictionaryRef = *const __CFDictionary;
 

core-foundation-sys/src/error.rs

@@ -0,0 +1,32 @@
+// Copyright 2016 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use libc::c_void;
+
+use base::{CFTypeID, CFIndex};
+use string::CFStringRef;
+
+#[repr(C)]
+pub struct __CFError(c_void);
+
+pub type CFErrorRef = *mut __CFError;
+
+extern "C" {
+    pub fn CFErrorGetTypeID() -> CFTypeID;
+
+    pub static kCFErrorDomainPOSIX: CFStringRef;
+    pub static kCFErrorDomainOSStatus: CFStringRef;
+    pub static kCFErrorDomainMach: CFStringRef;
+    pub static kCFErrorDomainCocoa: CFStringRef;
+
+    pub fn CFErrorGetDomain(err: CFErrorRef) -> CFStringRef;
+    pub fn CFErrorGetCode(err: CFErrorRef) -> CFIndex;
+
+    pub fn CFErrorCopyDescription(err: CFErrorRef) -> CFStringRef;
+}

core-foundation-sys/src/lib.rs

@@ -16,6 +16,7 @@ pub mod bundle;
 pub mod data;
 pub mod date;
 pub mod dictionary;
+pub mod error;
 pub mod number;
 pub mod runloop;
 pub mod set;

core-foundation-sys/src/number.rs

@@ -12,7 +12,7 @@ use libc::c_void;
 use base::{CFAllocatorRef, CFTypeID};
 
 #[repr(C)]
-struct __CFBoolean(c_void);
+pub struct __CFBoolean(c_void);
 
 pub type CFBooleanRef = *const __CFBoolean;
 
@@ -38,7 +38,7 @@ pub static kCFNumberFloat64Type:   CFNumberType = 6;
 // static kCFNumberMaxType:       CFNumberType = 16;
 
 #[repr(C)]
-struct __CFNumber;
+pub struct __CFNumber;
 
 pub type CFNumberRef = *const __CFNumber;
 

core-foundation-sys/src/runloop.rs

@@ -15,17 +15,17 @@ use date::{CFAbsoluteTime, CFTimeInterval};
 use string::CFStringRef;
 
 #[repr(C)]
-struct __CFRunLoop(c_void);
+pub struct __CFRunLoop(c_void);
 
 pub type CFRunLoopRef = *const __CFRunLoop;
 
 #[repr(C)]
-struct __CFRunLoopSource(c_void);
+pub struct __CFRunLoopSource(c_void);
 
 pub type CFRunLoopSourceRef = *const __CFRunLoopSource;
 
 #[repr(C)]
-struct __CFRunLoopObserver(c_void);
+pub struct __CFRunLoopObserver(c_void);
 
 pub type CFRunLoopObserverRef = *const __CFRunLoopObserver;
 
@@ -97,7 +97,7 @@ pub struct CFRunLoopTimerContext {
 pub type CFRunLoopTimerCallBack = extern "C" fn (timer: CFRunLoopTimerRef, info: *mut c_void);
 
 #[repr(C)]
-struct __CFRunLoopTimer;
+pub struct __CFRunLoopTimer;
 
 pub type CFRunLoopTimerRef = *const __CFRunLoopTimer;
 

core-foundation-sys/src/set.rs

@@ -29,7 +29,7 @@ pub struct CFSetCallBacks {
 }
 
 #[repr(C)]
-struct __CFSet(c_void);
+pub struct __CFSet(c_void);
 
 pub type CFSetRef = *const __CFSet;
 

core-foundation-sys/src/string.rs

@@ -188,7 +188,7 @@ pub type CFStringEncodings = CFIndex;
 //static kCFStringEncodingShiftJIS_X0213_00: CFStringEncoding = 0x0628; /* Deprecated */
 
 #[repr(C)]
-struct __CFString(c_void);
+pub struct __CFString(c_void);
 
 pub type CFStringRef = *const __CFString;
 

core-foundation-sys/src/url.rs

@@ -12,7 +12,7 @@ use base::{CFOptionFlags, CFIndex, CFAllocatorRef, Boolean, CFTypeID};
 use string::CFStringRef;
 
 #[repr(C)]
-struct __CFURL(c_void);
+pub struct __CFURL(c_void);
 
 pub type CFURLRef = *const __CFURL;
 

core-foundation/src/error.rs

@@ -0,0 +1,77 @@
+// Copyright 2016 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Core Foundation errors.
+
+use core_foundation_sys::error::*;
+use core_foundation_sys::base::CFRelease;
+use std::error::Error;
+use std::fmt;
+
+use base::{CFIndex, TCFType};
+use string::CFString;
+
+/// An error value.
+pub struct CFError(CFErrorRef);
+
+impl Drop for CFError {
+    fn drop(&mut self) {
+        unsafe {
+            CFRelease(self.as_CFTypeRef())
+        }
+    }
+}
+
+impl_TCFType!(CFError, CFErrorRef, CFErrorGetTypeID);
+
+impl fmt::Debug for CFError {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.debug_struct("CFError")
+           .field("domain", &self.domain())
+           .field("code", &self.code())
+           .field("description", &self.description())
+           .finish()
+    }
+}
+
+impl fmt::Display for CFError {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        write!(fmt, "{}", self.description())
+    }
+}
+
+impl Error for CFError {
+    fn description(&self) -> &str {
+        "a Core Foundation error"
+    }
+}
+
+impl CFError {
+    /// Returns a string identifying the domain with which this error is
+    /// associated.
+    pub fn domain(&self) -> CFString {
+        unsafe {
+            let s = CFErrorGetDomain(self.0);
+            CFString::wrap_under_get_rule(s)
+        }
+    }
+
+    /// Returns the code identifying this type of error.
+    pub fn code(&self) -> CFIndex {
+        unsafe { CFErrorGetCode(self.0) }
+    }
+
+    /// Returns a human-presentable description of the error.
+    pub fn description(&self) -> CFString {
+        unsafe {
+            let s = CFErrorCopyDescription(self.0);
+            CFString::wrap_under_create_rule(s)
+        }
+    }
+}

core-foundation/src/lib.rs

@@ -54,6 +54,7 @@ pub mod boolean;
 pub mod data;
 pub use core_foundation_sys::date; // back compat
 pub mod dictionary;
+pub mod error;
 pub mod number;
 pub mod set;
 pub mod string;