Reland "Move webrtc/{base => rtc_base}" (https://codereview.webrtc.org/2877023002)

Reland the base->rtc_base without adding stub headers (will be
done in follow-up CL). This preserves git blame history of all files.

BUG=webrtc:7634
NOTRY=True
TBR=kwiberg@webrtc.org

Change-Id: Iea3bb6f3f67b8374c96337b63e8f5aa3e6181012
Reviewed-on: https://chromium-review.googlesource.com/554611
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#18821}

webrtc/rtc_base/fileutils.cc

@@ -0,0 +1,133 @@
+/*
+ *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/base/fileutils.h"
+
+#include "webrtc/base/arraysize.h"
+#include "webrtc/base/checks.h"
+#include "webrtc/base/pathutils.h"
+#include "webrtc/base/stringutils.h"
+
+#if defined(WEBRTC_WIN)
+#include "webrtc/base/win32filesystem.h"
+#else
+#include "webrtc/base/unixfilesystem.h"
+#endif
+
+#if !defined(WEBRTC_WIN)
+#define MAX_PATH 260
+#endif
+
+namespace rtc {
+
+//////////////////////////
+// Directory Iterator   //
+//////////////////////////
+
+// A DirectoryIterator is created with a given directory. It originally points
+// to the first file in the directory, and can be advanecd with Next(). This
+// allows you to get information about each file.
+
+  // Constructor
+DirectoryIterator::DirectoryIterator()
+#ifdef WEBRTC_WIN
+    : handle_(INVALID_HANDLE_VALUE) {
+#else
+    : dir_(nullptr),
+      dirent_(nullptr){
+#endif
+}
+
+  // Destructor
+DirectoryIterator::~DirectoryIterator() {
+#if defined(WEBRTC_WIN)
+  if (handle_ != INVALID_HANDLE_VALUE)
+    ::FindClose(handle_);
+#else
+  if (dir_)
+    closedir(dir_);
+#endif
+}
+
+  // Starts traversing a directory.
+  // dir is the directory to traverse
+  // returns true if the directory exists and is valid
+bool DirectoryIterator::Iterate(const Pathname &dir) {
+  directory_ = dir.pathname();
+#if defined(WEBRTC_WIN)
+  if (handle_ != INVALID_HANDLE_VALUE)
+    ::FindClose(handle_);
+  std::string d = dir.pathname() + '*';
+  handle_ = ::FindFirstFile(ToUtf16(d).c_str(), &data_);
+  if (handle_ == INVALID_HANDLE_VALUE)
+    return false;
+#else
+  if (dir_ != nullptr)
+    closedir(dir_);
+  dir_ = ::opendir(directory_.c_str());
+  if (dir_ == nullptr)
+    return false;
+  dirent_ = readdir(dir_);
+  if (dirent_ == nullptr)
+    return false;
+
+  if (::stat(std::string(directory_ + Name()).c_str(), &stat_) != 0)
+    return false;
+#endif
+  return true;
+}
+
+  // Advances to the next file
+  // returns true if there were more files in the directory.
+bool DirectoryIterator::Next() {
+#if defined(WEBRTC_WIN)
+  return ::FindNextFile(handle_, &data_) == TRUE;
+#else
+  dirent_ = ::readdir(dir_);
+  if (dirent_ == nullptr)
+    return false;
+
+  return ::stat(std::string(directory_ + Name()).c_str(), &stat_) == 0;
+#endif
+}
+
+  // returns true if the file currently pointed to is a directory
+bool DirectoryIterator::IsDirectory() const {
+#if defined(WEBRTC_WIN)
+  return (data_.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != FALSE;
+#else
+  return S_ISDIR(stat_.st_mode);
+#endif
+}
+
+  // returns the name of the file currently pointed to
+std::string DirectoryIterator::Name() const {
+#if defined(WEBRTC_WIN)
+  return ToUtf8(data_.cFileName);
+#else
+  RTC_DCHECK(dirent_);
+  return dirent_->d_name;
+#endif
+}
+
+FilesystemInterface* Filesystem::default_filesystem_ = nullptr;
+
+FilesystemInterface *Filesystem::EnsureDefaultFilesystem() {
+  if (!default_filesystem_) {
+#if defined(WEBRTC_WIN)
+    default_filesystem_ = new Win32Filesystem();
+#else
+    default_filesystem_ = new UnixFilesystem();
+#endif
+  }
+  return default_filesystem_;
+}
+
+}  // namespace rtc