base/platform_file_win.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 #include "base/platform_file.h"
   6
   7 #include <io.h>
   8
   9 #include "base/files/file_path.h"
  10 #include "base/logging.h"
  11 #include "base/metrics/sparse_histogram.h"
  12 #include "base/threading/thread_restrictions.h"
  13
  14 namespace base {
  15 PlatformFile CreatePlatformFileUnsafe(const FilePath& name,
  16                                       int flags,
  17                                       bool* created,
  18                                       PlatformFileError* error) {
  19   base::ThreadRestrictions::AssertIOAllowed();
  20
  21   DWORD disposition = 0;
  22   if (created)
  23     *created = false;
  24
  25   if (flags & PLATFORM_FILE_OPEN)
  26     disposition = OPEN_EXISTING;
  27
  28   if (flags & PLATFORM_FILE_CREATE) {
  29     DCHECK(!disposition);
  30     disposition = CREATE_NEW;
  31   }
  32
  33   if (flags & PLATFORM_FILE_OPEN_ALWAYS) {
  34     DCHECK(!disposition);
  35     disposition = OPEN_ALWAYS;
  36   }
  37
  38   if (flags & PLATFORM_FILE_CREATE_ALWAYS) {
  39     DCHECK(!disposition);
  40     disposition = CREATE_ALWAYS;
  41   }
  42
  43   if (flags & PLATFORM_FILE_OPEN_TRUNCATED) {
  44     DCHECK(!disposition);
  45     DCHECK(flags & PLATFORM_FILE_WRITE);
  46     disposition = TRUNCATE_EXISTING;
  47   }
  48
  49   if (!disposition) {
  50     NOTREACHED();
  51     return NULL;
  52   }
  53
  54   DWORD access = 0;
  55   if (flags & PLATFORM_FILE_WRITE)
  56     access = GENERIC_WRITE;
  57   if (flags & PLATFORM_FILE_APPEND) {
  58     DCHECK(!access);
  59     access = FILE_APPEND_DATA;
  60   }
  61   if (flags & PLATFORM_FILE_READ)
  62     access |= GENERIC_READ;
  63   if (flags & PLATFORM_FILE_WRITE_ATTRIBUTES)
  64     access |= FILE_WRITE_ATTRIBUTES;
  65   if (flags & PLATFORM_FILE_EXECUTE)
  66     access |= GENERIC_EXECUTE;
  67
  68   DWORD sharing = (flags & PLATFORM_FILE_EXCLUSIVE_READ) ? 0 : FILE_SHARE_READ;
  69   if (!(flags & PLATFORM_FILE_EXCLUSIVE_WRITE))
  70     sharing |= FILE_SHARE_WRITE;
  71   if (flags & PLATFORM_FILE_SHARE_DELETE)
  72     sharing |= FILE_SHARE_DELETE;
  73
  74   DWORD create_flags = 0;
  75   if (flags & PLATFORM_FILE_ASYNC)
  76     create_flags |= FILE_FLAG_OVERLAPPED;
  77   if (flags & PLATFORM_FILE_TEMPORARY)
  78     create_flags |= FILE_ATTRIBUTE_TEMPORARY;
  79   if (flags & PLATFORM_FILE_HIDDEN)
  80     create_flags |= FILE_ATTRIBUTE_HIDDEN;
  81   if (flags & PLATFORM_FILE_DELETE_ON_CLOSE)
  82     create_flags |= FILE_FLAG_DELETE_ON_CLOSE;
  83   if (flags & PLATFORM_FILE_BACKUP_SEMANTICS)
  84     create_flags |= FILE_FLAG_BACKUP_SEMANTICS;
  85
  86   HANDLE file = CreateFile(name.value().c_str(), access, sharing, NULL,
  87                            disposition, create_flags, NULL);
  88
  89   if (created && (INVALID_HANDLE_VALUE != file)) {
  90     if (flags & (PLATFORM_FILE_OPEN_ALWAYS))
  91       *created = (ERROR_ALREADY_EXISTS != GetLastError());
  92     else if (flags & (PLATFORM_FILE_CREATE_ALWAYS | PLATFORM_FILE_CREATE))
  93       *created = true;
  94   }
  95
  96   if (error) {
  97     if (file != kInvalidPlatformFileValue)
  98       *error = PLATFORM_FILE_OK;
  99     else
 100       *error = LastErrorToPlatformFileError(GetLastError());
 101   }
 102
 103   return file;
 104 }
 105
 106 FILE* FdopenPlatformFile(PlatformFile file, const char* mode) {
 107   if (file == kInvalidPlatformFileValue)
 108     return NULL;
 109   int fd = _open_osfhandle(reinterpret_cast<intptr_t>(file), 0);
 110   if (fd < 0)
 111     return NULL;
 112   return _fdopen(fd, mode);
 113 }
 114
 115 bool ClosePlatformFile(PlatformFile file) {
 116   base::ThreadRestrictions::AssertIOAllowed();
 117   return (CloseHandle(file) != 0);
 118 }
 119
 120 int64 SeekPlatformFile(PlatformFile file,
 121                        PlatformFileWhence whence,
 122                        int64 offset) {
 123   base::ThreadRestrictions::AssertIOAllowed();
 124   if (file == kInvalidPlatformFileValue || offset < 0)
 125     return -1;
 126
 127   LARGE_INTEGER distance, res;
 128   distance.QuadPart = offset;
 129   DWORD move_method = static_cast<DWORD>(whence);
 130   if (!SetFilePointerEx(file, distance, &res, move_method))
 131     return -1;
 132   return res.QuadPart;
 133 }
 134
 135 int ReadPlatformFile(PlatformFile file, int64 offset, char* data, int size) {
 136   base::ThreadRestrictions::AssertIOAllowed();
 137   if (file == kInvalidPlatformFileValue || size < 0)
 138     return -1;
 139
 140   LARGE_INTEGER offset_li;
 141   offset_li.QuadPart = offset;
 142
 143   OVERLAPPED overlapped = {0};
 144   overlapped.Offset = offset_li.LowPart;
 145   overlapped.OffsetHigh = offset_li.HighPart;
 146
 147   DWORD bytes_read;
 148   if (::ReadFile(file, data, size, &bytes_read, &overlapped) != 0)
 149     return bytes_read;
 150   if (ERROR_HANDLE_EOF == GetLastError())
 151     return 0;
 152
 153   return -1;
 154 }
 155
 156 int ReadPlatformFileAtCurrentPos(PlatformFile file, char* data, int size) {
 157   base::ThreadRestrictions::AssertIOAllowed();
 158   if (file == kInvalidPlatformFileValue || size < 0)
 159     return -1;
 160
 161   DWORD bytes_read;
 162   if (::ReadFile(file, data, size, &bytes_read, NULL) != 0)
 163     return bytes_read;
 164   if (ERROR_HANDLE_EOF == GetLastError())
 165     return 0;
 166
 167   return -1;
 168 }
 169
 170 int ReadPlatformFileNoBestEffort(PlatformFile file, int64 offset, char* data,
 171                                  int size) {
 172   return ReadPlatformFile(file, offset, data, size);
 173 }
 174
 175 int ReadPlatformFileCurPosNoBestEffort(PlatformFile file,
 176                                        char* data, int size) {
 177   return ReadPlatformFileAtCurrentPos(file, data, size);
 178 }
 179
 180 int WritePlatformFile(PlatformFile file, int64 offset,
 181                       const char* data, int size) {
 182   base::ThreadRestrictions::AssertIOAllowed();
 183   if (file == kInvalidPlatformFileValue)
 184     return -1;
 185
 186   LARGE_INTEGER offset_li;
 187   offset_li.QuadPart = offset;
 188
 189   OVERLAPPED overlapped = {0};
 190   overlapped.Offset = offset_li.LowPart;
 191   overlapped.OffsetHigh = offset_li.HighPart;
 192
 193   DWORD bytes_written;
 194   if (::WriteFile(file, data, size, &bytes_written, &overlapped) != 0)
 195     return bytes_written;
 196
 197   return -1;
 198 }
 199
 200 int WritePlatformFileAtCurrentPos(PlatformFile file, const char* data,
 201                                   int size) {
 202   return WritePlatformFile(file, 0, data, size);
 203 }
 204
 205 int WritePlatformFileCurPosNoBestEffort(PlatformFile file,
 206                                         const char* data, int size) {
 207   return WritePlatformFile(file, 0, data, size);
 208 }
 209
 210 bool TruncatePlatformFile(PlatformFile file, int64 length) {
 211   base::ThreadRestrictions::AssertIOAllowed();
 212   if (file == kInvalidPlatformFileValue)
 213     return false;
 214
 215   // Get the current file pointer.
 216   LARGE_INTEGER file_pointer;
 217   LARGE_INTEGER zero;
 218   zero.QuadPart = 0;
 219   if (::SetFilePointerEx(file, zero, &file_pointer, FILE_CURRENT) == 0)
 220     return false;
 221
 222   LARGE_INTEGER length_li;
 223   length_li.QuadPart = length;
 224   // If length > file size, SetFilePointerEx() should extend the file
 225   // with zeroes on all Windows standard file systems (NTFS, FATxx).
 226   if (!::SetFilePointerEx(file, length_li, NULL, FILE_BEGIN))
 227     return false;
 228
 229   // Set the new file length and move the file pointer to its old position.
 230   // This is consistent with ftruncate()'s behavior, even when the file
 231   // pointer points to a location beyond the end of the file.
 232   return ((::SetEndOfFile(file) != 0) &&
 233           (::SetFilePointerEx(file, file_pointer, NULL, FILE_BEGIN) != 0));
 234 }
 235
 236 bool FlushPlatformFile(PlatformFile file) {
 237   base::ThreadRestrictions::AssertIOAllowed();
 238   return ((file != kInvalidPlatformFileValue) && ::FlushFileBuffers(file));
 239 }
 240
 241 bool TouchPlatformFile(PlatformFile file, const base::Time& last_access_time,
 242                        const base::Time& last_modified_time) {
 243   base::ThreadRestrictions::AssertIOAllowed();
 244   if (file == kInvalidPlatformFileValue)
 245     return false;
 246
 247   FILETIME last_access_filetime = last_access_time.ToFileTime();
 248   FILETIME last_modified_filetime = last_modified_time.ToFileTime();
 249   return (::SetFileTime(file, NULL, &last_access_filetime,
 250                         &last_modified_filetime) != 0);
 251 }
 252
 253 bool GetPlatformFileInfo(PlatformFile file, PlatformFileInfo* info) {
 254   base::ThreadRestrictions::AssertIOAllowed();
 255   if (!info)
 256     return false;
 257
 258   BY_HANDLE_FILE_INFORMATION file_info;
 259   if (GetFileInformationByHandle(file, &file_info) == 0)
 260     return false;
 261
 262   LARGE_INTEGER size;
 263   size.HighPart = file_info.nFileSizeHigh;
 264   size.LowPart = file_info.nFileSizeLow;
 265   info->size = size.QuadPart;
 266   info->is_directory =
 267       (file_info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
 268   info->is_symbolic_link = false; // Windows doesn't have symbolic links.
 269   info->last_modified = base::Time::FromFileTime(file_info.ftLastWriteTime);
 270   info->last_accessed = base::Time::FromFileTime(file_info.ftLastAccessTime);
 271   info->creation_time = base::Time::FromFileTime(file_info.ftCreationTime);
 272   return true;
 273 }
 274
 275 PlatformFileError LockPlatformFile(PlatformFile file) {
 276   BOOL result = LockFile(file, 0, 0, MAXDWORD, MAXDWORD);
 277   if (!result)
 278     return LastErrorToPlatformFileError(GetLastError());
 279   return PLATFORM_FILE_OK;
 280 }
 281
 282 PlatformFileError UnlockPlatformFile(PlatformFile file) {
 283   BOOL result = UnlockFile(file, 0, 0, MAXDWORD, MAXDWORD);
 284   if (!result)
 285     return LastErrorToPlatformFileError(GetLastError());
 286   return PLATFORM_FILE_OK;
 287 }
 288
 289 PlatformFileError LastErrorToPlatformFileError(DWORD last_error) {
 290   switch (last_error) {
 291     case ERROR_SHARING_VIOLATION:
 292       return PLATFORM_FILE_ERROR_IN_USE;
 293     case ERROR_FILE_EXISTS:
 294       return PLATFORM_FILE_ERROR_EXISTS;
 295     case ERROR_FILE_NOT_FOUND:
 296     case ERROR_PATH_NOT_FOUND:
 297       return PLATFORM_FILE_ERROR_NOT_FOUND;
 298     case ERROR_ACCESS_DENIED:
 299       return PLATFORM_FILE_ERROR_ACCESS_DENIED;
 300     case ERROR_TOO_MANY_OPEN_FILES:
 301       return PLATFORM_FILE_ERROR_TOO_MANY_OPENED;
 302     case ERROR_OUTOFMEMORY:
 303     case ERROR_NOT_ENOUGH_MEMORY:
 304       return PLATFORM_FILE_ERROR_NO_MEMORY;
 305     case ERROR_HANDLE_DISK_FULL:
 306     case ERROR_DISK_FULL:
 307     case ERROR_DISK_RESOURCES_EXHAUSTED:
 308       return PLATFORM_FILE_ERROR_NO_SPACE;
 309     case ERROR_USER_MAPPED_FILE:
 310       return PLATFORM_FILE_ERROR_INVALID_OPERATION;
 311     case ERROR_NOT_READY:
 312     case ERROR_SECTOR_NOT_FOUND:
 313     case ERROR_DEV_NOT_EXIST:
 314     case ERROR_IO_DEVICE:
 315     case ERROR_FILE_CORRUPT:
 316     case ERROR_DISK_CORRUPT:
 317       return PLATFORM_FILE_ERROR_IO;
 318     default:
 319       UMA_HISTOGRAM_SPARSE_SLOWLY("PlatformFile.UnknownErrors.Windows",
 320                                   last_error);
 321       return PLATFORM_FILE_ERROR_FAILED;
 322   }
 323 }
 324
 325 }  // namespace base