net/base/file_stream_context_posix.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // For 64-bit file access (off_t = off64_t, lseek64, etc).
   6 #define _FILE_OFFSET_BITS 64
   7
   8 #include "net/base/file_stream_context.h"
   9
  10 #include <errno.h>
  11 #include <fcntl.h>
  12 #include <sys/stat.h>
  13 #include <sys/types.h>
  14 #include <unistd.h>
  15
  16 #include "base/basictypes.h"
  17 #include "base/bind.h"
  18 #include "base/bind_helpers.h"
  19 #include "base/callback.h"
  20 #include "base/files/file_path.h"
  21 #include "base/location.h"
  22 #include "base/logging.h"
  23 #include "base/metrics/histogram.h"
  24 #include "base/posix/eintr_wrapper.h"
  25 #include "base/task_runner.h"
  26 #include "base/task_runner_util.h"
  27 #include "net/base/io_buffer.h"
  28 #include "net/base/net_errors.h"
  29
  30 #if defined(OS_ANDROID)
  31 // Android's bionic libc only supports the LFS transitional API.
  32 #define off_t off64_t
  33 #define lseek lseek64
  34 #define stat stat64
  35 #define fstat fstat64
  36 #endif
  37
  38 namespace net {
  39
  40 // We cast back and forth, so make sure it's the size we're expecting.
  41 COMPILE_ASSERT(sizeof(int64) == sizeof(off_t), off_t_64_bit);
  42
  43 // Make sure our Whence mappings match the system headers.
  44 COMPILE_ASSERT(FROM_BEGIN   == SEEK_SET &&
  45                FROM_CURRENT == SEEK_CUR &&
  46                FROM_END     == SEEK_END, whence_matches_system);
  47
  48 FileStream::Context::Context(const scoped_refptr<base::TaskRunner>& task_runner)
  49     : async_in_progress_(false),
  50       orphaned_(false),
  51       task_runner_(task_runner) {
  52 }
  53
  54 FileStream::Context::Context(base::File file,
  55                              const scoped_refptr<base::TaskRunner>& task_runner)
  56     : file_(file.Pass()),
  57       async_in_progress_(false),
  58       orphaned_(false),
  59       task_runner_(task_runner) {
  60 }
  61
  62 FileStream::Context::~Context() {
  63 }
  64
  65 int FileStream::Context::ReadAsync(IOBuffer* in_buf,
  66                                    int buf_len,
  67                                    const CompletionCallback& callback) {
  68   DCHECK(!async_in_progress_);
  69
  70   scoped_refptr<IOBuffer> buf = in_buf;
  71   const bool posted = base::PostTaskAndReplyWithResult(
  72       task_runner_.get(),
  73       FROM_HERE,
  74       base::Bind(&Context::ReadFileImpl, base::Unretained(this), buf, buf_len),
  75       base::Bind(&Context::OnAsyncCompleted,
  76                  base::Unretained(this),
  77                  IntToInt64(callback)));
  78   DCHECK(posted);
  79
  80   async_in_progress_ = true;
  81   return ERR_IO_PENDING;
  82 }
  83
  84 int FileStream::Context::WriteAsync(IOBuffer* in_buf,
  85                                     int buf_len,
  86                                     const CompletionCallback& callback) {
  87   DCHECK(!async_in_progress_);
  88
  89   scoped_refptr<IOBuffer> buf = in_buf;
  90   const bool posted = base::PostTaskAndReplyWithResult(
  91       task_runner_.get(),
  92       FROM_HERE,
  93       base::Bind(&Context::WriteFileImpl, base::Unretained(this), buf, buf_len),
  94       base::Bind(&Context::OnAsyncCompleted,
  95                  base::Unretained(this),
  96                  IntToInt64(callback)));
  97   DCHECK(posted);
  98
  99   async_in_progress_ = true;
 100   return ERR_IO_PENDING;
 101 }
 102
 103 FileStream::Context::IOResult FileStream::Context::SeekFileImpl(Whence whence,
 104                                                                 int64 offset) {
 105   off_t res = lseek(file_.GetPlatformFile(), static_cast<off_t>(offset),
 106                     static_cast<int>(whence));
 107   if (res == static_cast<off_t>(-1))
 108     return IOResult::FromOSError(errno);
 109
 110   return IOResult(res, 0);
 111 }
 112
 113 FileStream::Context::IOResult FileStream::Context::FlushFileImpl() {
 114   ssize_t res = HANDLE_EINTR(fsync(file_.GetPlatformFile()));
 115   if (res == -1)
 116     return IOResult::FromOSError(errno);
 117
 118   return IOResult(res, 0);
 119 }
 120
 121 FileStream::Context::IOResult FileStream::Context::ReadFileImpl(
 122     scoped_refptr<IOBuffer> buf,
 123     int buf_len) {
 124   // Loop in the case of getting interrupted by a signal.
 125   ssize_t res = HANDLE_EINTR(read(file_.GetPlatformFile(), buf->data(),
 126                                   static_cast<size_t>(buf_len)));
 127   if (res == -1)
 128     return IOResult::FromOSError(errno);
 129
 130   return IOResult(res, 0);
 131 }
 132
 133 FileStream::Context::IOResult FileStream::Context::WriteFileImpl(
 134     scoped_refptr<IOBuffer> buf,
 135     int buf_len) {
 136   ssize_t res = HANDLE_EINTR(write(file_.GetPlatformFile(), buf->data(),
 137                                    buf_len));
 138   if (res == -1)
 139     return IOResult::FromOSError(errno);
 140
 141   return IOResult(res, 0);
 142 }
 143
 144 }  // namespace net