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

base/base_paths_linux.cc

 // Copyright (c) 2010 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/base_paths.h"
 
 #include <unistd.h>
 #if defined(OS_FREEBSD)
 #include <sys/param.h>
 #include <sys/sysctl.h>
@@ skipping 19 matching lines @@
 // The name of this file relative to the source root. This is used for checking
 // that the source checkout is in the correct place.
 static const char kThisSourceFile[] = "base/base_paths_linux.cc";
 
 bool PathProviderPosix(int key, FilePath* result) {
   FilePath path;
   switch (key) {
     case base::FILE_EXE:
     case base::FILE_MODULE: {  // TODO(evanm): is this correct?
 #if defined(OS_LINUX)
-      char bin_dir[PATH_MAX + 1];
-      int bin_dir_size = readlink(kSelfExe, bin_dir, PATH_MAX);
-      if (bin_dir_size < 0 || bin_dir_size > PATH_MAX) {
+      FilePath bin_dir;
+      if (!file_util::ReadSymbolicLink(FilePath(kSelfExe), &bin_dir)) {
         NOTREACHED() << "Unable to resolve " << kSelfExe << ".";
         return false;
       }
-      bin_dir[bin_dir_size] = 0;
-      *result = FilePath(bin_dir);
+      *result = bin_dir;
       return true;
 #elif defined(OS_FREEBSD)
       int name[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
       char bin_dir[PATH_MAX + 1];
       size_t length = sizeof(bin_dir);
       int error = sysctl(name, 4, bin_dir, &length, NULL, 0);
       if (error < 0 || length == 0 || strlen(bin_dir) == 0) {
         NOTREACHED() << "Unable to resolve path.";
         return false;
       }
@@ skipping 51 matching lines @@
       scoped_ptr<base::Environment> env(base::Environment::Create());
       FilePath cache_dir(base::nix::GetXDGDirectory(env.get(), "XDG_CACHE_HOME",
                                                     ".cache"));
       *result = cache_dir;
       return true;
   }
   return false;
 }
 
 }  // namespace base