webkit/database/vfs_backend.cc

   1 // Copyright (c) 2011 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 "webkit/database/vfs_backend.h"
   6
   7 #include "base/file_path.h"
   8 #include "base/file_util.h"
   9 #include "base/logging.h"
  10 #include "third_party/sqlite/sqlite3.h"
  11
  12 namespace webkit_database {
  13
  14 static const int kFileTypeMask = 0x00007F00;
  15
  16 // static
  17 bool VfsBackend::OpenTypeIsReadWrite(int desired_flags) {
  18   return (desired_flags & SQLITE_OPEN_READWRITE) != 0;
  19 }
  20
  21 // static
  22 bool VfsBackend::OpenFileFlagsAreConsistent(int desired_flags) {
  23   const int file_type = desired_flags & kFileTypeMask;
  24   const bool is_exclusive = (desired_flags & SQLITE_OPEN_EXCLUSIVE) != 0;
  25   const bool is_delete = (desired_flags & SQLITE_OPEN_DELETEONCLOSE) != 0;
  26   const bool is_create = (desired_flags & SQLITE_OPEN_CREATE) != 0;
  27   const bool is_read_only = (desired_flags & SQLITE_OPEN_READONLY) != 0;
  28   const bool is_read_write = (desired_flags & SQLITE_OPEN_READWRITE) != 0;
  29
  30   // All files should be opened either read-write or read-only, but not both.
  31   if (is_read_only == is_read_write)
  32     return false;
  33
  34   // If a new file is created, it must also be writable.
  35   if (is_create && !is_read_write)
  36     return false;
  37
  38   // If we're accessing an existing file, we cannot give exclusive access, and
  39   // we can't delete it.
  40   // Normally, we'd also check that 'is_delete' is false for a main DB, main
  41   // journal or master journal file; however, when in incognito mode, we use
  42   // the SQLITE_OPEN_DELETEONCLOSE flag when opening those files too and keep
  43   // an open handle to them for as long as the incognito profile is around.
  44   if ((is_exclusive || is_delete) && !is_create)
  45     return false;
  46
  47   // Make sure we're opening the DB directory or that a file type is set.
  48   return (file_type == SQLITE_OPEN_MAIN_DB) ||
  49          (file_type == SQLITE_OPEN_TEMP_DB) ||
  50          (file_type == SQLITE_OPEN_MAIN_JOURNAL) ||
  51          (file_type == SQLITE_OPEN_TEMP_JOURNAL) ||
  52          (file_type == SQLITE_OPEN_SUBJOURNAL) ||
  53          (file_type == SQLITE_OPEN_MASTER_JOURNAL) ||
  54          (file_type == SQLITE_OPEN_TRANSIENT_DB);
  55 }
  56
  57 // static
  58 void VfsBackend::OpenFile(const FilePath& file_path,
  59                           int desired_flags,
  60                           base::PlatformFile* file_handle) {
  61   DCHECK(!file_path.empty());
  62
  63   // Verify the flags for consistency and create the database
  64   // directory if it doesn't exist.
  65   if (!OpenFileFlagsAreConsistent(desired_flags) ||
  66       !file_util::CreateDirectory(file_path.DirName()))
  67     return;
  68
  69   int flags = 0;
  70   flags |= base::PLATFORM_FILE_READ;
  71   if (desired_flags & SQLITE_OPEN_READWRITE)
  72     flags |= base::PLATFORM_FILE_WRITE;
  73
  74   if (!(desired_flags & SQLITE_OPEN_MAIN_DB)) {
  75     flags |= base::PLATFORM_FILE_EXCLUSIVE_READ |
  76              base::PLATFORM_FILE_EXCLUSIVE_WRITE;
  77   }
  78
  79   flags |= ((desired_flags & SQLITE_OPEN_CREATE) ?
  80       base::PLATFORM_FILE_OPEN_ALWAYS : base::PLATFORM_FILE_OPEN);
  81
  82   if (desired_flags & SQLITE_OPEN_EXCLUSIVE) {
  83     flags |= base::PLATFORM_FILE_EXCLUSIVE_READ |
  84              base::PLATFORM_FILE_EXCLUSIVE_WRITE;
  85   }
  86
  87   if (desired_flags & SQLITE_OPEN_DELETEONCLOSE) {
  88     flags |= base::PLATFORM_FILE_TEMPORARY | base::PLATFORM_FILE_HIDDEN |
  89              base::PLATFORM_FILE_DELETE_ON_CLOSE;
  90   }
  91
  92   // This flag will allow us to delete the file later on from the browser
  93   // process.
  94   flags |= base::PLATFORM_FILE_SHARE_DELETE;
  95
  96   // Try to open/create the DB file.
  97   *file_handle =
  98       base::CreatePlatformFile(file_path, flags, NULL, NULL);
  99 }
 100
 101 // static
 102 void VfsBackend::OpenTempFileInDirectory(
 103     const FilePath& dir_path,
 104     int desired_flags,
 105     base::PlatformFile* file_handle) {
 106   // We should be able to delete temp files when they're closed
 107   // and create them as needed
 108   if (!(desired_flags & SQLITE_OPEN_DELETEONCLOSE) ||
 109       !(desired_flags & SQLITE_OPEN_CREATE)) {
 110     return;
 111   }
 112
 113   // Get a unique temp file name in the database directory.
 114   FilePath temp_file_path;
 115   if (!file_util::CreateTemporaryFileInDir(dir_path, &temp_file_path))
 116     return;
 117
 118   OpenFile(temp_file_path, desired_flags, file_handle);
 119 }
 120
 121 // static
 122 int VfsBackend::DeleteFile(const FilePath& file_path, bool sync_dir) {
 123   if (!file_util::PathExists(file_path))
 124     return SQLITE_OK;
 125   if (!file_util::Delete(file_path, false))
 126     return SQLITE_IOERR_DELETE;
 127
 128   int error_code = SQLITE_OK;
 129 #if defined(OS_POSIX)
 130   if (sync_dir) {
 131     base::PlatformFile dir_fd = base::CreatePlatformFile(
 132         file_path.DirName(), base::PLATFORM_FILE_READ, NULL, NULL);
 133     if (dir_fd == base::kInvalidPlatformFileValue) {
 134       error_code = SQLITE_CANTOPEN;
 135     } else {
 136       if (fsync(dir_fd))
 137         error_code = SQLITE_IOERR_DIR_FSYNC;
 138       base::ClosePlatformFile(dir_fd);
 139     }
 140   }
 141 #endif
 142   return error_code;
 143 }
 144
 145 // static
 146 uint32 VfsBackend::GetFileAttributes(const FilePath& file_path) {
 147 #if defined(OS_WIN)
 148   uint32 attributes = ::GetFileAttributes(file_path.value().c_str());
 149 #elif defined(OS_POSIX)
 150   uint32 attributes = 0;
 151   if (!access(file_path.value().c_str(), R_OK))
 152     attributes |= static_cast<uint32>(R_OK);
 153   if (!access(file_path.value().c_str(), W_OK))
 154     attributes |= static_cast<uint32>(W_OK);
 155   if (!attributes)
 156     attributes = -1;
 157 #endif
 158   return attributes;
 159 }
 160
 161 // static
 162 int64 VfsBackend::GetFileSize(const FilePath& file_path) {
 163   int64 size = 0;
 164   return (file_util::GetFileSize(file_path, &size) ? size : 0);
 165 }
 166
 167 } // namespace webkit_database