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_util.h"
  26 #include "net/base/io_buffer.h"
  27 #include "net/base/net_errors.h"
  28
  29 #if defined(OS_ANDROID)
  30 // Android's bionic libc only supports the LFS transitional API.
  31 #define off_t off64_t
  32 #define lseek lseek64
  33 #define stat stat64
  34 #define fstat fstat64
  35 #endif
  36
  37 namespace net {
  38
  39 // We cast back and forth, so make sure it's the size we're expecting.
  40 COMPILE_ASSERT(sizeof(int64) == sizeof(off_t), off_t_64_bit);
  41
  42 // Make sure our Whence mappings match the system headers.
  43 COMPILE_ASSERT(FROM_BEGIN   == SEEK_SET &&
  44                FROM_CURRENT == SEEK_CUR &&
  45                FROM_END     == SEEK_END, whence_matches_system);
  46
  47 FileStream::Context::Context(const BoundNetLog& bound_net_log,
  48                              const scoped_refptr<base::TaskRunner>& task_runner)
  49     : file_(base::kInvalidPlatformFileValue),
  50       record_uma_(false),
  51       async_in_progress_(false),
  52       orphaned_(false),
  53       bound_net_log_(bound_net_log),
  54       task_runner_(task_runner) {
  55 }
  56
  57 FileStream::Context::Context(base::PlatformFile file,
  58                              const BoundNetLog& bound_net_log,
  59                              int /* open_flags */,
  60                              const scoped_refptr<base::TaskRunner>& task_runner)
  61     : file_(file),
  62       record_uma_(false),
  63       async_in_progress_(false),
  64       orphaned_(false),
  65       bound_net_log_(bound_net_log),
  66       task_runner_(task_runner) {
  67 }
  68
  69 FileStream::Context::~Context() {
  70 }
  71
  72 int64 FileStream::Context::GetFileSize() const {
  73   struct stat info;
  74   if (fstat(file_, &info) != 0) {
  75     IOResult result = IOResult::FromOSError(errno);
  76     RecordError(result, FILE_ERROR_SOURCE_GET_SIZE);
  77     return result.result;
  78   }
  79
  80   return static_cast<int64>(info.st_size);
  81 }
  82
  83 int FileStream::Context::ReadAsync(IOBuffer* in_buf,
  84                                    int buf_len,
  85                                    const CompletionCallback& callback) {
  86   DCHECK(!async_in_progress_);
  87
  88   scoped_refptr<IOBuffer> buf = in_buf;
  89   const bool posted = base::PostTaskAndReplyWithResult(
  90       task_runner_.get(),
  91       FROM_HERE,
  92       base::Bind(&Context::ReadFileImpl, base::Unretained(this), buf, buf_len),
  93       base::Bind(&Context::ProcessAsyncResult,
  94                  base::Unretained(this),
  95                  IntToInt64(callback),
  96                  FILE_ERROR_SOURCE_READ));
  97   DCHECK(posted);
  98
  99   async_in_progress_ = true;
 100   return ERR_IO_PENDING;
 101 }
 102
 103 int FileStream::Context::ReadSync(char* in_buf, int buf_len) {
 104   scoped_refptr<IOBuffer> buf = new WrappedIOBuffer(in_buf);
 105   IOResult result = ReadFileImpl(buf, buf_len);
 106   RecordError(result, FILE_ERROR_SOURCE_READ);
 107   return result.result;
 108 }
 109
 110 int FileStream::Context::WriteAsync(IOBuffer* in_buf,
 111                                     int buf_len,
 112                                     const CompletionCallback& callback) {
 113   DCHECK(!async_in_progress_);
 114
 115   scoped_refptr<IOBuffer> buf = in_buf;
 116   const bool posted = base::PostTaskAndReplyWithResult(
 117       task_runner_.get(),
 118       FROM_HERE,
 119       base::Bind(&Context::WriteFileImpl, base::Unretained(this), buf, buf_len),
 120       base::Bind(&Context::ProcessAsyncResult,
 121                  base::Unretained(this),
 122                  IntToInt64(callback),
 123                  FILE_ERROR_SOURCE_WRITE));
 124   DCHECK(posted);
 125
 126   async_in_progress_ = true;
 127   return ERR_IO_PENDING;
 128 }
 129
 130 int FileStream::Context::WriteSync(const char* in_buf, int buf_len) {
 131   scoped_refptr<IOBuffer> buf = new WrappedIOBuffer(in_buf);
 132   IOResult result = WriteFileImpl(buf, buf_len);
 133   RecordError(result, FILE_ERROR_SOURCE_WRITE);
 134   return result.result;
 135 }
 136
 137 int FileStream::Context::Truncate(int64 bytes) {
 138   if (ftruncate(file_, bytes) != 0) {
 139     IOResult result = IOResult::FromOSError(errno);
 140     RecordError(result, FILE_ERROR_SOURCE_SET_EOF);
 141     return result.result;
 142   }
 143
 144   return bytes;
 145 }
 146
 147 FileStream::Context::IOResult FileStream::Context::SeekFileImpl(Whence whence,
 148                                                                 int64 offset) {
 149   off_t res = lseek(file_, static_cast<off_t>(offset),
 150                     static_cast<int>(whence));
 151   if (res == static_cast<off_t>(-1))
 152     return IOResult::FromOSError(errno);
 153
 154   return IOResult(res, 0);
 155 }
 156
 157 FileStream::Context::IOResult FileStream::Context::FlushFileImpl() {
 158   ssize_t res = HANDLE_EINTR(fsync(file_));
 159   if (res == -1)
 160     return IOResult::FromOSError(errno);
 161
 162   return IOResult(res, 0);
 163 }
 164
 165 FileStream::Context::IOResult FileStream::Context::ReadFileImpl(
 166     scoped_refptr<IOBuffer> buf,
 167     int buf_len) {
 168   // Loop in the case of getting interrupted by a signal.
 169   ssize_t res = HANDLE_EINTR(read(file_, buf->data(),
 170                                   static_cast<size_t>(buf_len)));
 171   if (res == -1)
 172     return IOResult::FromOSError(errno);
 173
 174   return IOResult(res, 0);
 175 }
 176
 177 FileStream::Context::IOResult FileStream::Context::WriteFileImpl(
 178     scoped_refptr<IOBuffer> buf,
 179     int buf_len) {
 180   ssize_t res = HANDLE_EINTR(write(file_, buf->data(), buf_len));
 181   if (res == -1)
 182     return IOResult::FromOSError(errno);
 183
 184   return IOResult(res, 0);
 185 }
 186
 187 }  // namespace net