Update from https://crrev.com/302630

sandbox/linux/services/broker_process.h

-// 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.
-
-#ifndef SANDBOX_LINUX_SERVICES_BROKER_PROCESS_H_
-#define SANDBOX_LINUX_SERVICES_BROKER_PROCESS_H_
-
-#include <string>
-#include <vector>
-
-#include "base/basictypes.h"
-#include "base/callback_forward.h"
-#include "base/pickle.h"
-#include "base/process/process.h"
-#include "sandbox/sandbox_export.h"
-
-namespace sandbox {
-
-// Create a new "broker" process to which we can send requests via an IPC
-// channel.
-// This is a low level IPC mechanism that is suitable to be called from a
-// signal handler.
-// A process would typically create a broker process before entering
-// sandboxing.
-// 1. BrokerProcess open_broker(read_whitelist, write_whitelist);
-// 2. CHECK(open_broker.Init(NULL));
-// 3. Enable sandbox.
-// 4. Use open_broker.Open() to open files.
-class SANDBOX_EXPORT BrokerProcess {
- public:
-  // |denied_errno| is the error code returned when methods such as Open()
-  // or Access() are invoked on a file which is not in the whitelist. EACCESS
-  // would be a typical value.
-  // |allowed_r_files| and |allowed_w_files| are white lists of files that can
-  // be opened later via the Open() API, respectively for reading and writing.
-  // A file available read-write should be listed in both.
-  // |fast_check_in_client| and |quiet_failures_for_tests| are reserved for
-  // unit tests, don't use it.
-  explicit BrokerProcess(int denied_errno,
-                         const std::vector<std::string>& allowed_r_files,
-                         const std::vector<std::string>& allowed_w_files,
-                         bool fast_check_in_client = true,
-                         bool quiet_failures_for_tests = false);
-  ~BrokerProcess();
-  // Will initialize the broker process. There should be no threads at this
-  // point, since we need to fork().
-  // broker_process_init_callback will be called in the new broker process,
-  // after fork() returns.
-  bool Init(const base::Callback<bool(void)>& broker_process_init_callback);
-
-  // Can be used in place of access(). Will be async signal safe.
-  // X_OK will always return an error in practice since the broker process
-  // doesn't support execute permissions.
-  // It's similar to the access() system call and will return -errno on errors.
-  int Access(const char* pathname, int mode) const;
-  // Can be used in place of open(). Will be async signal safe.
-  // The implementation only supports certain white listed flags and will
-  // return -EPERM on other flags.
-  // It's similar to the open() system call and will return -errno on errors.
-  int Open(const char* pathname, int flags) const;
-
-  int broker_pid() const { return broker_pid_; }
-
- private:
-  enum IPCCommands {
-    kCommandInvalid = 0,
-    kCommandOpen,
-    kCommandAccess,
-  };
-  int PathAndFlagsSyscall(enum IPCCommands command_type,
-                          const char* pathname,
-                          int flags) const;
-  bool HandleRequest() const;
-  bool HandleRemoteCommand(IPCCommands command_type,
-                           int reply_ipc,
-                           const Pickle& read_pickle,
-                           PickleIterator iter) const;
-
-  void AccessFileForIPC(const std::string& requested_filename,
-                        int mode,
-                        Pickle* write_pickle) const;
-  void OpenFileForIPC(const std::string& requested_filename,
-                      int flags,
-                      Pickle* write_pickle,
-                      std::vector<int>* opened_files) const;
-  bool GetFileNameIfAllowedToAccess(const char*, int, const char**) const;
-  bool GetFileNameIfAllowedToOpen(const char*, int, const char**) const;
-  const int denied_errno_;
-  bool initialized_;               // Whether we've been through Init() yet.
-  bool is_child_;                  // Whether we're the child (broker process).
-  bool fast_check_in_client_;      // Whether to forward a request that we know
-                                   // will be denied to the broker.
-  bool quiet_failures_for_tests_;  // Disable certain error message when
-                                   // testing for failures.
-  pid_t broker_pid_;               // The PID of the broker (child).
-  const std::vector<std::string> allowed_r_files_;  // Files allowed for read.
-  const std::vector<std::string> allowed_w_files_;  // Files allowed for write.
-  int ipc_socketpair_;  // Our communication channel to parent or child.
-  DISALLOW_IMPLICIT_CONSTRUCTORS(BrokerProcess);
-
-  friend class BrokerProcessTestHelper;
-};
-
-}  // namespace sandbox
-
-#endif  // SANDBOX_LINUX_SERVICES_BROKER_PROCESS_H_