Add write and read/write support to FileStream (renamed from FileInputStream)...

net/base/file_input_stream_posix.cc

Index: net/base/file_input_stream_posix.cc
===================================================================
--- net/base/file_input_stream_posix.cc	(revision 4450)
+++ net/base/file_input_stream_posix.cc	(working copy)
@@ -1,143 +0,0 @@
-// Copyright (c) 2008 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.
-
-// For 64-bit file access (off_t = off64_t, lseek64, etc).
-#define _FILE_OFFSET_BITS 64
-
-#include "net/base/file_input_stream.h"
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
-
-#include "base/basictypes.h"
-#include "base/logging.h"
-#include "base/message_loop.h"
-#include "base/string_util.h"
-#include "net/base/net_errors.h"
-
-// We cast back and forth, so make sure it's the size we're expecting.
-COMPILE_ASSERT(sizeof(int64) == sizeof(off_t), off_t_64_bit);
-
-// Make sure our Whence mappings match the system headers.
-COMPILE_ASSERT(net::FROM_BEGIN   == SEEK_SET &&
-               net::FROM_CURRENT == SEEK_CUR &&
-               net::FROM_END     == SEEK_END, whence_matches_system);
-
-namespace net {
-
-// FileInputStream::AsyncContext ----------------------------------------------
-
-// TODO(deanm): Figure out how to best do async IO.
-class FileInputStream::AsyncContext {
- public:
-
-  CompletionCallback* callback() const { return NULL; }
- private:
-
-  DISALLOW_COPY_AND_ASSIGN(AsyncContext);
-};
-
-// FileInputStream ------------------------------------------------------------
-
-FileInputStream::FileInputStream() : fd_(-1) {
-  DCHECK(!IsOpen());
-}
-
-FileInputStream::~FileInputStream() {
-  Close();
-}
-
-void FileInputStream::Close() {
-  if (fd_ != -1) {
-    if (close(fd_) != 0) {
-      NOTREACHED();
-    }
-    fd_ = -1;
-  }
-  async_context_.reset();
-}
-
-// Map from errno to net error codes.
-static int64 MapErrorCode(int err) {
-  switch(err) {
-    case ENOENT:
-      return ERR_FILE_NOT_FOUND;
-    case EACCES:
-      return ERR_ACCESS_DENIED;
-    default:
-      LOG(WARNING) << "Unknown error " << err << " mapped to net::ERR_FAILED";
-      return ERR_FAILED;
-  }
-}
-
-int FileInputStream::Open(const std::wstring& path, bool asynchronous_mode) {
-  // We don't need O_LARGEFILE here since we set the 64-bit off_t feature.
-  fd_ = open(WideToUTF8(path).c_str(), 0, O_RDONLY);
-  if (fd_ == -1)
-    return MapErrorCode(errno);
-
-  return OK;
-}
-
-bool FileInputStream::IsOpen() const {
-  return fd_ != -1;
-}
-
-int64 FileInputStream::Seek(Whence whence, int64 offset) {
-  if (!IsOpen())
-    return ERR_UNEXPECTED;
-
-  // If we're in async, make sure we don't have a request in flight.
-  DCHECK(!async_context_.get() || !async_context_->callback());
-  
-  off_t res = lseek(fd_, static_cast<off_t>(offset), static_cast<int>(whence));
-  if (res == static_cast<off_t>(-1))
-    return MapErrorCode(errno);
-
-  return res;
-}
-
-int64 FileInputStream::Available() {
-  if (!IsOpen())
-    return ERR_UNEXPECTED;
-
-  int64 cur_pos = Seek(FROM_CURRENT, 0);
-  if (cur_pos < 0)
-    return cur_pos;
-
-  struct stat info;
-  if (fstat(fd_, &info) != 0)
-    return MapErrorCode(errno);
-
-  int64 size = static_cast<int64>(info.st_size);
-  DCHECK(size >= cur_pos);
-
-  return size - cur_pos;
-}
-
-// TODO(deanm): async.
-int FileInputStream::Read(
-    char* buf, int buf_len, CompletionCallback* callback) {
-  // read(..., 0) will return 0, which indicates end-of-file.
-  DCHECK(buf_len > 0 && buf_len <= SSIZE_MAX);
-
-  if (!IsOpen())
-    return ERR_UNEXPECTED;
-
-  // Loop in the case of getting interrupted by a signal.
-  for (;;) {
-    ssize_t res = read(fd_, buf, static_cast<size_t>(buf_len));
-    if (res == static_cast<ssize_t>(-1)) {
-      if (errno == EINTR)
-        continue;
-      return MapErrorCode(errno);
-    }
-    return static_cast<int>(res);
-  }
-}
-
-}  // namespace net