Bulletproof the url going into a std::string and ensure it's not going to...

chrome/browser/cocoa/web_drop_target.mm

 // Copyright (c) 2009 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.
 
 #import "chrome/browser/cocoa/web_drop_target.h"
 
 #include "base/sys_string_conversions.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
 #import "third_party/mozilla/include/NSPasteboard+Utils.h"
@@ skipping 166 matching lines @@
 
   // The getURLs:andTitles: will already validate URIs so we don't need to
   // again. However, if the URI is a local file, it won't be prefixed with
   // file://, which is what GURL expects. We can detect that case because the
   // resulting URI will have no valid scheme, and we'll assume it's a local
   // file. The arrays returned are both of NSString's.
   NSArray* urls = nil;
   NSArray* titles = nil;
   [pboard getURLs:&urls andTitles:&titles];
   NSString* urlString = [urls objectAtIndex:0];
-  NSURL* url = [NSURL URLWithString:urlString];
-  if (![url scheme])
-    urlString = [[NSURL fileURLWithPath:urlString] absoluteString];
-  data->url = GURL([urlString UTF8String]);
-  data->url_title = base::SysNSStringToUTF16([titles objectAtIndex:0]);
+  if ([urlString length]) {
+    NSURL* url = [NSURL URLWithString:urlString];
+    if (![url scheme])
+      urlString = [[NSURL fileURLWithPath:urlString] absoluteString];
+    // Check again just to make sure to not assign NULL into a std::string,
+    // which throws an exception.
+    const char* utf8Url = [urlString UTF8String];
+    if (utf8Url) {
+      data->url = GURL(utf8Url);
+      data->url_title = base::SysNSStringToUTF16([titles objectAtIndex:0]);

[viettrungluu, 2009/11/06 21:29:17]

I'm 99.99% sure that |SysNSStringToUTF16()| chokes if passed nil, so this should
be something like:

  if (NSString* title = [titles objectAtIndex:0])
    data->url_title = base::SysNSStringToUTF16(title);

(|-objectAtIndex:| shouldn't return nil, but is there any guarantee that
|titles| isn't nil?)

+    }
+  }
 }
 
 // Given |data|, which should not be nil, fill it in using the contents of the
 // given pasteboard.
 - (void)populateWebDropData:(WebDropData*)data
              fromPasteboard:(NSPasteboard*)pboard {
   DCHECK(data);
   DCHECK(pboard);
   NSArray* types = [pboard types];
 
@@ skipping 25 matching lines @@
         if (exists && !isDir)
           data->filenames.push_back(base::SysNSStringToUTF16(filename));
       }
     }
   }
 
   // TODO(pinkerton): Get file contents.
 }
 
 @end