Implement RemovableDeviceNotifications for Mac

base/sys_string_conversions_mac.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/sys_string_conversions.h"
 
 #import <Foundation/Foundation.h>
 
 #include <vector>
 
@@ skipping 145 matching lines @@
   return (NSString*)base::mac::CFTypeRefToNSObjectAutorelease(
       SysUTF8ToCFStringRef(utf8));
 }
 
 NSString* SysUTF16ToNSString(const string16& utf16) {
   return (NSString*)base::mac::CFTypeRefToNSObjectAutorelease(
       SysUTF16ToCFStringRef(utf16));
 }
 
 std::string SysCFStringRefToUTF8(CFStringRef ref) {
+  if (!ref)

[Mark Mentovai, 2012/09/12 21:05:15]

This intentionally does not operate on NULL input for safe round-tripping. You
should adjust the caller instead of this.

[sail, 2012/09/12 22:38:26]

Done.
(I'm not sure I understand this.  Round-tripping would imply
SysUTF8ToCFString(NULL) returning NULL. But we're using references.)

[Mark Mentovai, 2012/09/12 22:45:26]

sail wrote:
Right, and there’s no such thing as a NULL reference, so this function should
crash as any other function that operates on CFStrings would upon encountering a
NULL CFString.

There’s already a way to represent an empty CFString, and it’s not NULL.
UTF8ToCFString(CFStringToUTF8(x)) == x, but as you modified this function
previously, that’s not the case for NULL. Since you can’t express a NULL object
(as opposed to a pointer), the correct thing to do is crash.

+    return std::string();
   return CFStringToSTLStringWithEncodingT<std::string>(ref,
                                                        kNarrowStringEncoding);
 }
 
 string16 SysCFStringRefToUTF16(CFStringRef ref) {
+  if (!ref)
+    return string16();
   return CFStringToSTLStringWithEncodingT<string16>(ref,
                                                     kMediumStringEncoding);
 }
 
 std::string SysNSStringToUTF8(NSString* nsstring) {
   if (!nsstring)
     return std::string();
   return SysCFStringRefToUTF8(reinterpret_cast<CFStringRef>(nsstring));
 }
 
 string16 SysNSStringToUTF16(NSString* nsstring) {
   if (!nsstring)
     return string16();
   return SysCFStringRefToUTF16(reinterpret_cast<CFStringRef>(nsstring));
 }
 
 }  // namespace base