Mac TimeMachine File Exclusions

base/mac/mac_util.mm

 // Copyright (c) 2011 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/mac/mac_util.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/file_path.h"
 #include "base/logging.h"
@@ skipping 220 matching lines @@
 void ActivateProcess(pid_t pid) {
   ProcessSerialNumber process;
   OSStatus status = GetProcessForPID(pid, &process);
   if (status == noErr) {
     SetFrontProcess(&process);
   } else {
     LOG(WARNING) << "Unable to get process for pid " << pid;
   }
 }
 
 bool SetFileBackupExclusion(const FilePath& file_path, bool exclude) {

[Mark Mentovai, 2011/05/25 01:14:35]

This entire function should be cleaned up substantially. It’s OK to do the
cleanup in a future change.

1. Remove all of the temporary directory checking stuff leading up to the early
return. It solves something that’s only a problem with excludeByPath and is no
longer necessary with the metadata attribute-based exclude.

2. Remove the |exclude| argument and allays act as if true had been passed in.
There are no callers that set it to false, except for a test. We shouldn’t need
to worry about testing a behavior we never use if we can simplify things by
removing support for that behavior.

[mrossetti, 2011/05/26 21:02:40]

Done.

   NSString* filePath =
       [NSString stringWithUTF8String:file_path.value().c_str()];
 
   // If being asked to exclude something in a tmp directory, just lie and say it
   // was done.  TimeMachine will already ignore tmp directories.  This keeps the
   // temporary profiles used by unittests from being added to the exclude list.
   // Otherwise, as /Library/Preferences/com.apple.TimeMachine.plist grows the
   // bots slow down due to reading/writing all the temporary profiles used over
   // time.
 
   NSString* tmpDir = NSTemporaryDirectory();
   // Make sure the temp dir is terminated with a slash
   if (tmpDir && ![tmpDir hasSuffix:@"/"])
     tmpDir = [tmpDir stringByAppendingString:@"/"];
   // '/var' is a link to '/private/var', make sure to check both forms.
   NSString* privateTmpDir = nil;
   if ([tmpDir hasPrefix:@"/var/"])
     privateTmpDir = [@"/private" stringByAppendingString:tmpDir];
 
   if ((tmpDir && [filePath hasPrefix:tmpDir]) ||
       (privateTmpDir && [filePath hasPrefix:privateTmpDir]) ||
       [filePath hasPrefix:@"/tmp/"] ||
       [filePath hasPrefix:@"/var/tmp/"] ||
       [filePath hasPrefix:@"/private/tmp/"] ||
       [filePath hasPrefix:@"/private/var/tmp/"]) {
     return true;
   }
 
   NSURL* url = [NSURL fileURLWithPath:filePath];
-  // Note that we always set CSBackupSetItemExcluded's excludeByPath param
-  // to true.  This prevents a problem with toggling the setting: if the file
-  // is excluded with excludeByPath set to true then excludeByPath must
-  // also be true when un-excluding the file, otherwise the un-excluding
-  // will be ignored.
+  // When excludeByPath is true the application must be running with root
+  // privileges (admin for 10.6 and earlier) but the URL does not have to
+  // already exist. When excludeByPath is false the URL must already exist but
+  // can be used in non-root (or admin as above) mode. We use false so that
+  // non-root (or admin) users don't get their TimeMachine drive filled up with
+  // unnecessary backups.
   bool success =
-      CSBackupSetItemExcluded((CFURLRef)url, exclude, true) == noErr;
+      CSBackupSetItemExcluded((CFURLRef)url, exclude, false) == noErr;
   if (!success)

[Mark Mentovai, 2011/05/25 01:14:35]

Style nit (present in the existing code): this needs {braces} because it
consumes multiple lines.

[mrossetti, 2011/05/26 21:02:40]

Done.

     LOG(WARNING) << "Failed to set backup exclusion for file '"
                  << file_path.value().c_str() << "'.  Continuing.";
   return success;
 }
 
 void SetProcessName(CFStringRef process_name) {
   if (!process_name || CFStringGetLength(process_name) == 0) {
     NOTREACHED() << "SetProcessName given bad name.";
     return;
   }
@@ skipping 186 matching lines @@
   ScopedCFTypeRef<LSSharedFileListItemRef> item(GetLoginItemForApp());
   if (!item.get()) {
     LOG(ERROR) << "Process launched at Login but can't access Login Item List.";
     return false;
   }
   return IsHiddenLoginItem(item);
 }
 
 }  // namespace mac
 }  // namespace base