implement things needed to run net/disk_cache/backend_unittest

base/file_util_linux.cc

Index: base/file_util_linux.cc
===================================================================
--- base/file_util_linux.cc	(revision 2109)
+++ base/file_util_linux.cc	(working copy)
@@ -25,6 +25,7 @@
   return true;
 }
 
+// Does not copy attributes, permissions, metadata etc.
 bool CopyFile(const std::wstring& from_path, const std::wstring& to_path) {
   int infile = open(WideToUTF8(from_path).c_str(), O_RDONLY);
   if (infile < 0)
@@ -71,4 +72,49 @@
   return result;
 }
 
+// TODO: Make this function symlink-aware.
+// Does not copy attributes, permissions, metadata etc.
+bool CopyDirectory(const std::wstring& from_path, const std::wstring& to_path,
+                   bool recursive) {
+  if (!CreateDirectory(to_path)) {
+    return false;
+  }
+
+  FileEnumerator enumerator(from_path, false, FileEnumerator::FILES);
+  std::wstring path;
+  while ((path = enumerator.Next()) != L"") {
+    path = GetFilenameFromPath(path);
+    std::wstring from = from_path;
+    AppendToPath(&from, path);
+
+    std::wstring to = to_path;
+    AppendToPath(&to, path);
+
+    if (!CopyFile(from, to)) {
+      // If some files have been copied successfully they won't be deleted.
+      return false;
+    }
+  }
+
+  if (recursive) {
+    FileEnumerator enumerator(from_path, false, FileEnumerator::DIRECTORIES);
+    std::wstring path;
+    while ((path = enumerator.Next()) != L"") {
+      path = GetFilenameFromPath(path);
+      std::wstring from = from_path;
+      AppendToPath(&from, path);
+
+      std::wstring to = to_path;
+      AppendToPath(&to, path);
+
+      if (!CopyDirectory(from, to, true)) {
+        // If some files have been copied successfully they won't be deleted.
+        return false;
+      }
+    }
+  }
+
+  return true;
+}
+
 }  // namespace file_util