Clean up some nits in base::NativeLibrary.

base/native_library_mac.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/native_library.h"
 
 #include <dlfcn.h>
 #include <mach-o/getsect.h>
 
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_restrictions.h"
 
 namespace base {
 
 static NativeLibraryObjCStatus GetObjCStatusForImage(
     const void* function_pointer) {
   Dl_info info;
   if (!dladdr(function_pointer, &info))
     return OBJC_UNKNOWN;
 
-  // See if the the image contains an "ObjC image info" segment. This method

[Lei Zhang, 2016/06/07 01:25:39]

And self-reviewing after sending out the CL... I probably should retain the
comment and just remove line 30, right?

-  // of testing is used in _CFBundleGrokObjcImageInfoFromFile in
-  // CF-744/CFBundle.c, around lines 2447-2474.
-  //
-  // In 32-bit images, ObjC can be recognized in __OBJC,__image_info, whereas
-  // in 64-bit, the data is in __DATA,__objc_imageinfo.
-#if __LP64__
   const section_64* section = getsectbynamefromheader_64(
       reinterpret_cast<const struct mach_header_64*>(info.dli_fbase),
       SEG_DATA, "__objc_imageinfo");
-#else
-  const section* section = getsectbynamefromheader(
-      reinterpret_cast<const struct mach_header*>(info.dli_fbase),
-      SEG_OBJC, "__image_info");
-#endif
-  return section == NULL ? OBJC_NOT_PRESENT : OBJC_PRESENT;
+  return section ? OBJC_PRESENT : OBJC_NOT_PRESENT;
 }
 
 std::string NativeLibraryLoadError::ToString() const {
   return message;
 }
 
 // static
-NativeLibrary LoadNativeLibrary(const base::FilePath& library_path,
+NativeLibrary LoadNativeLibrary(const FilePath& library_path,
                                 NativeLibraryLoadError* error) {
   // dlopen() etc. open the file off disk.
   if (library_path.Extension() == "dylib" || !DirectoryExists(library_path)) {
     void* dylib = dlopen(library_path.value().c_str(), RTLD_LAZY);
     if (!dylib) {
       if (error)
         error->message = dlerror();
       return NULL;
     }
     NativeLibrary native_lib = new NativeLibraryStruct();
     native_lib->type = DYNAMIC_LIB;
     native_lib->dylib = dylib;
     native_lib->objc_status = OBJC_UNKNOWN;
     return native_lib;
   }
-  base::ScopedCFTypeRef<CFURLRef> url(CFURLCreateFromFileSystemRepresentation(
+  ScopedCFTypeRef<CFURLRef> url(CFURLCreateFromFileSystemRepresentation(
       kCFAllocatorDefault,
       (const UInt8*)library_path.value().c_str(),
       library_path.value().length(),
       true));
   if (!url)
     return NULL;
   CFBundleRef bundle = CFBundleCreate(kCFAllocatorDefault, url.get());
   if (!bundle)
     return NULL;
 
@@ skipping 20 matching lines @@
                "segment. library->objc_status = " << library->objc_status;
     // Deliberately do not CFRelease the bundle or dlclose the dylib because
     // doing so can corrupt the ObjC runtime method caches. See
     // http://crbug.com/172319 for details.
   }
   delete library;
 }
 
 // static
 void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
-                                          const char* name) {
+                                          StringPiece name) {
   void* function_pointer = NULL;
 
   // Get the function pointer using the right API for the type.
   if (library->type == BUNDLE) {
-    base::ScopedCFTypeRef<CFStringRef> symbol_name(CFStringCreateWithCString(
-        kCFAllocatorDefault, name, kCFStringEncodingUTF8));
+    ScopedCFTypeRef<CFStringRef> symbol_name(CFStringCreateWithCString(
+        kCFAllocatorDefault, name.data(), kCFStringEncodingUTF8));
     function_pointer = CFBundleGetFunctionPointerForName(library->bundle,
                                                          symbol_name);
   } else {
-    function_pointer = dlsym(library->dylib, name);
+    function_pointer = dlsym(library->dylib, name.data());
   }
 
   // If this library hasn't been tested for having ObjC, use the function
   // pointer to look up the section information for the library.
   if (function_pointer && library->objc_status == OBJC_UNKNOWN)
     library->objc_status = GetObjCStatusForImage(function_pointer);
 
   return function_pointer;
 }
 
 // static
-string16 GetNativeLibraryName(const string16& name) {
-  return name + ASCIIToUTF16(".dylib");
+string16 GetNativeLibraryName(StringPiece16 name) {
+  return name.as_string() + ASCIIToUTF16(".dylib");

[Lei Zhang, 2016/06/07 01:39:52]

BTW, I suspect this is wrong, and it should be lib${foo}.dylib, as seen in my
mac's component build's out directory, and the references to
libclearkeycdm.dylib. Looking to fix this and get rid of the ifdefs surrounding
the references to libclearkeycdm.dylib in C++ code.

[xhwang, 2016/06/07 16:39:27]

+1

[Mark Mentovai, 2016/06/10 20:06:18]

Lei Zhang wrote:
If you fix this, fix the header too.

 }
 
 }  // namespace base