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      1 /*
      2  * Copyright (C) 2009 Google Inc. All rights reserved.
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions are
      6  * met:
      7  *
      8  *     * Redistributions of source code must retain the above copyright
      9  * notice, this list of conditions and the following disclaimer.
     10  *     * Redistributions in binary form must reproduce the above
     11  * copyright notice, this list of conditions and the following disclaimer
     12  * in the documentation and/or other materials provided with the
     13  * distribution.
     14  *     * Neither the name of Google Inc. nor the names of its
     15  * contributors may be used to endorse or promote products derived from
     16  * this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  */
     30 
     31 #include "config.h"
     32 #include "SQLiteFileSystem.h"
     33 
     34 #include "PlatformBridge.h"
     35 #include <sqlite3.h>
     36 
     37 #include <fcntl.h>
     38 #include <string.h>
     39 #include <unistd.h>
     40 
     41 using namespace WebCore;
     42 
     43 // Defined in Chromium's codebase in third_party/sqlite/src/os_unix.c
     44 extern "C" {
     45 void chromium_sqlite3_initialize_unix_sqlite3_file(sqlite3_file* file);
     46 int chromium_sqlite3_fill_in_unix_sqlite3_file(sqlite3_vfs* vfs, int fd, int dirfd, sqlite3_file* file, const char* fileName, int noLock);
     47 int chromium_sqlite3_get_reusable_file_handle(sqlite3_file* file, const char* fileName, int flags, int* fd);
     48 void chromium_sqlite3_update_reusable_file_handle(sqlite3_file* file, int fd, int flags);
     49 void chromium_sqlite3_destroy_reusable_file_handle(sqlite3_file* file);
     50 }
     51 
     52 // Chromium's Posix implementation of SQLite VFS
     53 namespace {
     54 
     55 // Opens a file.
     56 //
     57 // vfs - pointer to the sqlite3_vfs object.
     58 // fileName - the name of the file.
     59 // id - the structure that will manipulate the newly opened file.
     60 // desiredFlags - the desired open mode flags.
     61 // usedFlags - the actual open mode flags that were used.
     62 int chromiumOpen(sqlite3_vfs* vfs, const char* fileName,
     63                  sqlite3_file* id, int desiredFlags, int* usedFlags)
     64 {
     65     chromium_sqlite3_initialize_unix_sqlite3_file(id);
     66     int fd = -1;
     67     int result = chromium_sqlite3_get_reusable_file_handle(id, fileName, desiredFlags, &fd);
     68     if (result != SQLITE_OK)
     69         return result;
     70 
     71     if (fd < 0) {
     72         fd = PlatformBridge::databaseOpenFile(fileName, desiredFlags);
     73         if ((fd < 0) && (desiredFlags & SQLITE_OPEN_READWRITE)) {
     74             int newFlags = (desiredFlags & ~(SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE)) | SQLITE_OPEN_READONLY;
     75             fd = PlatformBridge::databaseOpenFile(fileName, newFlags);
     76         }
     77     }
     78     if (fd < 0) {
     79         chromium_sqlite3_destroy_reusable_file_handle(id);
     80         return SQLITE_CANTOPEN;
     81     }
     82 
     83     if (usedFlags)
     84         *usedFlags = desiredFlags;
     85     chromium_sqlite3_update_reusable_file_handle(id, fd, desiredFlags);
     86 
     87     fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
     88 
     89     // The mask 0x00007F00 gives us the 7 bits that determine the type of the file SQLite is trying to open.
     90     int fileType = desiredFlags & 0x00007F00;
     91     int noLock = (fileType != SQLITE_OPEN_MAIN_DB);
     92     result = chromium_sqlite3_fill_in_unix_sqlite3_file(vfs, fd, -1, id, fileName, noLock);
     93     if (result != SQLITE_OK)
     94         chromium_sqlite3_destroy_reusable_file_handle(id);
     95     return result;
     96 }
     97 
     98 // Deletes the given file.
     99 //
    100 // vfs - pointer to the sqlite3_vfs object.
    101 // fileName - the name of the file.
    102 // syncDir - determines if the directory to which this file belongs
    103 //           should be synched after the file is deleted.
    104 int chromiumDelete(sqlite3_vfs*, const char* fileName, int syncDir)
    105 {
    106     return PlatformBridge::databaseDeleteFile(fileName, syncDir);
    107 }
    108 
    109 // Check the existance and status of the given file.
    110 //
    111 // vfs - pointer to the sqlite3_vfs object.
    112 // fileName - the name of the file.
    113 // flag - the type of test to make on this file.
    114 // res - the result.
    115 int chromiumAccess(sqlite3_vfs*, const char* fileName, int flag, int* res)
    116 {
    117     int attr = static_cast<int>(PlatformBridge::databaseGetFileAttributes(fileName));
    118     if (attr < 0) {
    119         *res = 0;
    120         return SQLITE_OK;
    121     }
    122 
    123     switch (flag) {
    124     case SQLITE_ACCESS_EXISTS:
    125         *res = 1;   // if the file doesn't exist, attr < 0
    126         break;
    127     case SQLITE_ACCESS_READWRITE:
    128         *res = (attr & W_OK) && (attr & R_OK);
    129         break;
    130     case SQLITE_ACCESS_READ:
    131         *res = (attr & R_OK);
    132         break;
    133     default:
    134         return SQLITE_ERROR;
    135     }
    136 
    137     return SQLITE_OK;
    138 }
    139 
    140 // Turns a relative pathname into a full pathname.
    141 //
    142 // vfs - pointer to the sqlite3_vfs object.
    143 // relativePath - the relative path.
    144 // bufSize - the size of the output buffer in bytes.
    145 // absolutePath - the output buffer where the absolute path will be stored.
    146 int chromiumFullPathname(sqlite3_vfs* vfs, const char* relativePath,
    147                          int, char* absolutePath)
    148 {
    149     // The renderer process doesn't need to know the absolute path of the file
    150     sqlite3_snprintf(vfs->mxPathname, absolutePath, "%s", relativePath);
    151     return SQLITE_OK;
    152 }
    153 
    154 #ifndef SQLITE_OMIT_LOAD_EXTENSION
    155 // Returns NULL, thus disallowing loading libraries in the renderer process.
    156 //
    157 // vfs - pointer to the sqlite3_vfs object.
    158 // fileName - the name of the shared library file.
    159 void* chromiumDlOpen(sqlite3_vfs*, const char*)
    160 {
    161     return 0;
    162 }
    163 #else
    164 #define chromiumDlOpen 0
    165 #endif // SQLITE_OMIT_LOAD_EXTENSION
    166 
    167 } // namespace
    168 
    169 namespace WebCore {
    170 
    171 void SQLiteFileSystem::registerSQLiteVFS()
    172 {
    173     sqlite3_vfs* unix_vfs = sqlite3_vfs_find("unix");
    174     static sqlite3_vfs chromium_vfs = {
    175         1,
    176         unix_vfs->szOsFile,
    177         unix_vfs->mxPathname,
    178         0,
    179         "chromium_vfs",
    180         unix_vfs->pAppData,
    181         chromiumOpen,
    182         chromiumDelete,
    183         chromiumAccess,
    184         chromiumFullPathname,
    185         chromiumDlOpen,
    186         unix_vfs->xDlError,
    187         unix_vfs->xDlSym,
    188         unix_vfs->xDlClose,
    189         unix_vfs->xRandomness,
    190         unix_vfs->xSleep,
    191         unix_vfs->xCurrentTime,
    192         unix_vfs->xGetLastError
    193     };
    194     sqlite3_vfs_register(&chromium_vfs, 0);
    195 }
    196 
    197 } // namespace WebCore
    198