Fix some potential Mach port leaks from mach_host_self using a new ScopedMachPort class.

base/sys_info_mac.cc

 // 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_info.h"
 
 #include <ApplicationServices/ApplicationServices.h>
 #include <CoreServices/CoreServices.h>
 #include <mach/mach_host.h>
 #include <mach/mach_init.h>
 #include <sys/sysctl.h>
 #include <sys/types.h>
 
 #include "base/logging.h"
+#include "base/mac/scoped_mach_port.h"
 #include "base/stringprintf.h"
 
 namespace base {
 
 // static
 std::string SysInfo::OperatingSystemName() {
   return "Mac OS X";
 }
 
 // static
@@ skipping 12 matching lines @@
   Gestalt(gestaltSystemVersionMinor,
       reinterpret_cast<SInt32*>(minor_version));
   Gestalt(gestaltSystemVersionBugFix,
       reinterpret_cast<SInt32*>(bugfix_version));
 }
 
 // static
 int64 SysInfo::AmountOfPhysicalMemory() {
   struct host_basic_info hostinfo;
   mach_msg_type_number_t count = HOST_BASIC_INFO_COUNT;
-  int result = host_info(mach_host_self(),
+  base::mac::ScopedMachPort<host_name_port_t> host(mach_host_self());
+  int result = host_info(host,
                          HOST_BASIC_INFO,
                          reinterpret_cast<host_info_t>(&hostinfo),
                          &count);
   if (result != KERN_SUCCESS) {
     NOTREACHED();
     return 0;
   }
   DCHECK_EQ(HOST_BASIC_INFO_COUNT, count);
   return static_cast<int64>(hostinfo.max_mem);
 }
 
 // static
 std::string SysInfo::CPUModelName() {
   char name[256];
   size_t len = arraysize(name);
   if (sysctlbyname("machdep.cpu.brand_string", &name, &len, NULL, 0) == 0)
     return name;
   return std::string();
 }
 
 }  // namespace base