The Tor Browser: security/sandbox/chromium/base/platform

security/sandbox/chromium/base/platform_file.h@b8a032363ba2 (annotated)

security/sandbox/chromium/base/platform_file.h

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 // 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 BASE_PLATFORM_FILE_H_
 #define BASE_PLATFORM_FILE_H_
 #include "build/build_config.h"
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 #include <string>
 #include "base/base_export.h"
 #include "base/basictypes.h"
 #include "base/files/file_path.h"
 #include "base/time/time.h"
 namespace base {
 // PLATFORM_FILE_(OPEN|CREATE).* are mutually exclusive. You should specify
 // exactly one of the five (possibly combining with other flags) when opening
 // or creating a file.
 // PLATFORM_FILE_(WRITE|APPEND) are mutually exclusive. This is so that APPEND
 // behavior will be consistent with O_APPEND on POSIX.
 enum PlatformFileFlags {
   PLATFORM_FILE_OPEN = 1 << 0,             // Opens a file, only if it exists.
   PLATFORM_FILE_CREATE = 1 << 1,           // Creates a new file, only if it
                                            // does not already exist.
   PLATFORM_FILE_OPEN_ALWAYS = 1 << 2,      // May create a new file.
   PLATFORM_FILE_CREATE_ALWAYS = 1 << 3,    // May overwrite an old file.
   PLATFORM_FILE_OPEN_TRUNCATED = 1 << 4,   // Opens a file and truncates it,
                                            // only if it exists.
   PLATFORM_FILE_READ = 1 << 5,
   PLATFORM_FILE_WRITE = 1 << 6,
   PLATFORM_FILE_APPEND = 1 << 7,
   PLATFORM_FILE_EXCLUSIVE_READ = 1 << 8,   // EXCLUSIVE is opposite of Windows
                                            // SHARE
   PLATFORM_FILE_EXCLUSIVE_WRITE = 1 << 9,
   PLATFORM_FILE_ASYNC = 1 << 10,
   PLATFORM_FILE_TEMPORARY = 1 << 11,       // Used on Windows only
   PLATFORM_FILE_HIDDEN = 1 << 12,          // Used on Windows only
   PLATFORM_FILE_DELETE_ON_CLOSE = 1 << 13,
   PLATFORM_FILE_WRITE_ATTRIBUTES = 1 << 14,  // Used on Windows only
   PLATFORM_FILE_ENUMERATE = 1 << 15,         // May enumerate directory
   PLATFORM_FILE_SHARE_DELETE = 1 << 16,      // Used on Windows only
   PLATFORM_FILE_TERMINAL_DEVICE = 1 << 17,   // Serial port flags
   PLATFORM_FILE_BACKUP_SEMANTICS = 1 << 18,  // Used on Windows only
   PLATFORM_FILE_EXECUTE = 1 << 19,           // Used on Windows only
 };
 // PLATFORM_FILE_ERROR_ACCESS_DENIED is returned when a call fails because of
 // a filesystem restriction. PLATFORM_FILE_ERROR_SECURITY is returned when a
 // browser policy doesn't allow the operation to be executed.
 enum PlatformFileError {
   PLATFORM_FILE_OK = 0,
   PLATFORM_FILE_ERROR_FAILED = -1,
   PLATFORM_FILE_ERROR_IN_USE = -2,
   PLATFORM_FILE_ERROR_EXISTS = -3,
   PLATFORM_FILE_ERROR_NOT_FOUND = -4,
   PLATFORM_FILE_ERROR_ACCESS_DENIED = -5,
   PLATFORM_FILE_ERROR_TOO_MANY_OPENED = -6,
   PLATFORM_FILE_ERROR_NO_MEMORY = -7,
   PLATFORM_FILE_ERROR_NO_SPACE = -8,
   PLATFORM_FILE_ERROR_NOT_A_DIRECTORY = -9,
   PLATFORM_FILE_ERROR_INVALID_OPERATION = -10,
   PLATFORM_FILE_ERROR_SECURITY = -11,
   PLATFORM_FILE_ERROR_ABORT = -12,
   PLATFORM_FILE_ERROR_NOT_A_FILE = -13,
   PLATFORM_FILE_ERROR_NOT_EMPTY = -14,
   PLATFORM_FILE_ERROR_INVALID_URL = -15,
   PLATFORM_FILE_ERROR_IO = -16,
   // Put new entries here and increment PLATFORM_FILE_ERROR_MAX.
   PLATFORM_FILE_ERROR_MAX = -17
 };
 // This explicit mapping matches both FILE_ on Windows and SEEK_ on Linux.
 enum PlatformFileWhence {
   PLATFORM_FILE_FROM_BEGIN   = 0,
   PLATFORM_FILE_FROM_CURRENT = 1,
   PLATFORM_FILE_FROM_END     = 2
 };
 // Used to hold information about a given file.
 // If you add more fields to this structure (platform-specific fields are OK),
 // make sure to update all functions that use it in file_util_{win|posix}.cc
 // too, and the ParamTraits<base::PlatformFileInfo> implementation in
 // chrome/common/common_param_traits.cc.
 struct BASE_EXPORT PlatformFileInfo {
   PlatformFileInfo();
   ~PlatformFileInfo();
   // The size of the file in bytes.  Undefined when is_directory is true.
   int64 size;
   // True if the file corresponds to a directory.
   bool is_directory;
   // True if the file corresponds to a symbolic link.
   bool is_symbolic_link;
   // The last modified time of a file.
   base::Time last_modified;
   // The last accessed time of a file.
   base::Time last_accessed;
   // The creation time of a file.
   base::Time creation_time;
 };
 #if defined(OS_WIN)
 typedef HANDLE PlatformFile;
 const PlatformFile kInvalidPlatformFileValue = INVALID_HANDLE_VALUE;
 PlatformFileError LastErrorToPlatformFileError(DWORD saved_errno);
 #elif defined(OS_POSIX)
 typedef int PlatformFile;
 const PlatformFile kInvalidPlatformFileValue = -1;
 PlatformFileError ErrnoToPlatformFileError(int saved_errno);
 #endif
 // Creates or opens the given file. If |created| is provided, it will be set to
 // true if a new file was created [or an old one truncated to zero length to
 // simulate a new file, which can happen with PLATFORM_FILE_CREATE_ALWAYS], and
 // false otherwise.  |error| can be NULL.
 //
 // This function fails with 'access denied' if the |name| contains path
 // traversal ('..') components.
 BASE_EXPORT PlatformFile CreatePlatformFile(const FilePath& name,
                                             int flags,
                                             bool* created,
                                             PlatformFileError* error);
 // Same as CreatePlatformFile but allows paths with traversal (like \..\)
 // components. Use only with extreme care.
 BASE_EXPORT PlatformFile CreatePlatformFileUnsafe(const FilePath& name,
                                                   int flags,
                                                   bool* created,
                                                   PlatformFileError* error);
 BASE_EXPORT FILE* FdopenPlatformFile(PlatformFile file, const char* mode);
 // Closes a file handle. Returns |true| on success and |false| otherwise.
 BASE_EXPORT bool ClosePlatformFile(PlatformFile file);
 // Changes current position in the file to an |offset| relative to an origin
 // defined by |whence|. Returns the resultant current position in the file
 // (relative to the start) or -1 in case of error.
 BASE_EXPORT int64 SeekPlatformFile(PlatformFile file,
                                    PlatformFileWhence whence,
                                    int64 offset);
 // Reads the given number of bytes (or until EOF is reached) starting with the
 // given offset. Returns the number of bytes read, or -1 on error. Note that
 // this function makes a best effort to read all data on all platforms, so it is
 // not intended for stream oriented files but instead for cases when the normal
 // expectation is that actually |size| bytes are read unless there is an error.
 BASE_EXPORT int ReadPlatformFile(PlatformFile file, int64 offset,
                                  char* data, int size);
 // Same as above but without seek.
 BASE_EXPORT int ReadPlatformFileAtCurrentPos(PlatformFile file,
                                              char* data, int size);
 // Reads the given number of bytes (or until EOF is reached) starting with the
 // given offset, but does not make any effort to read all data on all platforms.
 // Returns the number of bytes read, or -1 on error.
 BASE_EXPORT int ReadPlatformFileNoBestEffort(PlatformFile file, int64 offset,
                                              char* data, int size);
 // Same as above but without seek.
 BASE_EXPORT int ReadPlatformFileCurPosNoBestEffort(PlatformFile file,
                                                    char* data, int size);
 // Writes the given buffer into the file at the given offset, overwritting any
 // data that was previously there. Returns the number of bytes written, or -1
 // on error. Note that this function makes a best effort to write all data on
 // all platforms.
 // Ignores the offset and writes to the end of the file if the file was opened
 // with PLATFORM_FILE_APPEND.
 BASE_EXPORT int WritePlatformFile(PlatformFile file, int64 offset,
                                   const char* data, int size);
 // Save as above but without seek.
 BASE_EXPORT int WritePlatformFileAtCurrentPos(PlatformFile file,
                                               const char* data, int size);
 // Save as above but does not make any effort to write all data on all
 // platforms. Returns the number of bytes written, or -1 on error.
 BASE_EXPORT int WritePlatformFileCurPosNoBestEffort(PlatformFile file,
                                                     const char* data, int size);
 // Truncates the given file to the given length. If |length| is greater than
 // the current size of the file, the file is extended with zeros. If the file
 // doesn't exist, |false| is returned.
 BASE_EXPORT bool TruncatePlatformFile(PlatformFile file, int64 length);
 // Flushes the buffers of the given file.
 BASE_EXPORT bool FlushPlatformFile(PlatformFile file);
 // Touches the given file.
 BASE_EXPORT bool TouchPlatformFile(PlatformFile file,
                                    const Time& last_access_time,
                                    const Time& last_modified_time);
 // Returns some information for the given file.
 BASE_EXPORT bool GetPlatformFileInfo(PlatformFile file, PlatformFileInfo* info);
 // Use this class to pass ownership of a PlatformFile to a receiver that may or
 // may not want to accept it.  This class does not own the storage for the
 // PlatformFile.
 //
 // EXAMPLE:
 //
 //  void MaybeProcessFile(PassPlatformFile pass_file) {
 //    if (...) {
 //      PlatformFile file = pass_file.ReleaseValue();
 //      // Now, we are responsible for closing |file|.
 //    }
 //  }
 //
 //  void OpenAndMaybeProcessFile(const FilePath& path) {
 //    PlatformFile file = CreatePlatformFile(path, ...);
 //    MaybeProcessFile(PassPlatformFile(&file));
 //    if (file != kInvalidPlatformFileValue)
 //      ClosePlatformFile(file);
 //  }
 //
 class BASE_EXPORT PassPlatformFile {
  public:
   explicit PassPlatformFile(PlatformFile* value) : value_(value) {
   }
   // Called to retrieve the PlatformFile stored in this object.  The caller
   // gains ownership of the PlatformFile and is now responsible for closing it.
   // Any subsequent calls to this method will return an invalid PlatformFile.
   PlatformFile ReleaseValue() {
     PlatformFile temp = *value_;
     *value_ = kInvalidPlatformFileValue;
     return temp;
   }
  private:
   PlatformFile* value_;
 };
 }  // namespace base
 #endif  // BASE_PLATFORM_FILE_H_

The Tor Browser / annotate

security/sandbox/chromium/base/platform_file.h@b8a032363ba2 (annotated)

security/sandbox/chromium/base/platform_file.h