Start using file_util symlink code, now that it's available.

base/process_util_linux.cc

 // 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.
 
 #include "base/process_util.h"
 
 #include <ctype.h>
 #include <dirent.h>
 #include <dlfcn.h>
 #include <errno.h>
@@ skipping 93 matching lines @@
     }
   }
   NOTREACHED();
   return -1;
 }
 
 FilePath GetProcessExecutablePath(ProcessHandle process) {
   FilePath stat_file("/proc");
   stat_file = stat_file.Append(base::IntToString(process));
   stat_file = stat_file.Append("exe");
-  char exename[2048];
-  ssize_t len = readlink(stat_file.value().c_str(), exename, sizeof(exename));
-  if (len < 1) {
+  FilePath exe_name;
+  if (!file_util::ReadSymbolicLink(stat_file, &exe_name)) {
     // No such process.  Happens frequently in e.g. TerminateAllChromeProcesses
     return FilePath();
   }
-  return FilePath(std::string(exename, len));
+  return exe_name;
 }
 
 ProcessIterator::ProcessIterator(const ProcessFilter* filter)
     : filter_(filter) {
   procfs_dir_ = opendir("/proc");
 }
 
 ProcessIterator::~ProcessIterator() {
   if (procfs_dir_) {
     closedir(procfs_dir_);
@@ skipping 566 matching lines @@
 
   if (!file_util::PathExists(oom_adj))
     return false;
 
   std::string score_str = base::IntToString(score);
   return (static_cast<int>(score_str.length()) ==
           file_util::WriteFile(oom_adj, score_str.c_str(), score_str.length()));
 }
 
 }  // namespace base