third_party/sqlite/webdb.patch

   1 The WebDatabase implementation in the renderer users a custom vfs to
   2 broker file open and other requests.  This modifies the built-in vfs
   3 implementation to let that code share much of the implementation
   4 details.
   5
   6 diff --git src/os_unix.c src/os_unix.c
   7 index ef04a72..e5e1509 100644
   8 --- src/os_unix.c
   9 +++ src/os_unix.c
  10 @@ -3496,9 +3496,16 @@ typedef const sqlite3_io_methods *(*finder_type)(const char*,unixFile*);
  11  */
  12
  13  /*
  14 +** Initializes a unixFile structure with zeros.
  15 +*/
  16 +void initUnixFile(sqlite3_file* file) {
  17 +  memset(file, 0, sizeof(unixFile));
  18 +}
  19 +
  20 +/*
  21  ** Initialize the contents of the unixFile structure pointed to by pId.
  22  */
  23 -static int fillInUnixFile(
  24 +int fillInUnixFile(
  25    sqlite3_vfs *pVfs,      /* Pointer to vfs object */
  26    int h,                  /* Open file descriptor of file being opened */
  27    int dirfd,              /* Directory file descriptor */
  28 @@ -3812,6 +3819,73 @@ static UnixUnusedFd *findReusableFd(const char *zPath, int flags){
  29  }
  30
  31  /*
  32 +** Initializes a unixFile structure with zeros.
  33 +*/
  34 +void chromium_sqlite3_initialize_unix_sqlite3_file(sqlite3_file* file) {
  35 +  memset(file, 0, sizeof(unixFile));
  36 +}
  37 +
  38 +int chromium_sqlite3_fill_in_unix_sqlite3_file(sqlite3_vfs* vfs,
  39 +                                               int fd,
  40 +                                               int dirfd,
  41 +                                               sqlite3_file* file,
  42 +                                               const char* fileName,
  43 +                                               int noLock,
  44 +                                               int isDelete) {
  45 +  return fillInUnixFile(vfs, fd, dirfd, file, fileName, noLock, isDelete, 0);
  46 +}
  47 +
  48 +/*
  49 +** Search for an unused file descriptor that was opened on the database file.
  50 +** If a suitable file descriptor if found, then it is stored in *fd; otherwise,
  51 +** *fd is not modified.
  52 +**
  53 +** If a reusable file descriptor is not found, and a new UnixUnusedFd cannot
  54 +** be allocated, SQLITE_NOMEM is returned. Otherwise, SQLITE_OK is returned.
  55 +*/
  56 +int chromium_sqlite3_get_reusable_file_handle(sqlite3_file* file,
  57 +                                              const char* fileName,
  58 +                                              int flags,
  59 +                                              int* fd) {
  60 +  unixFile* unixSQLite3File = (unixFile*)file;
  61 +  int fileType = flags & 0xFFFFFF00;
  62 +  if (fileType == SQLITE_OPEN_MAIN_DB) {
  63 +    UnixUnusedFd *unusedFd = findReusableFd(fileName, flags);
  64 +    if (unusedFd) {
  65 +      *fd = unusedFd->fd;
  66 +    } else {
  67 +      unusedFd = sqlite3_malloc(sizeof(*unusedFd));
  68 +      if (!unusedFd) {
  69 +        return SQLITE_NOMEM;
  70 +      }
  71 +    }
  72 +    unixSQLite3File->pUnused = unusedFd;
  73 +  }
  74 +  return SQLITE_OK;
  75 +}
  76 +
  77 +/*
  78 +** Marks 'fd' as the unused file descriptor for 'pFile'.
  79 +*/
  80 +void chromium_sqlite3_update_reusable_file_handle(sqlite3_file* file,
  81 +                                                  int fd,
  82 +                                                  int flags) {
  83 +  unixFile* unixSQLite3File = (unixFile*)file;
  84 +  if (unixSQLite3File->pUnused) {
  85 +    unixSQLite3File->pUnused->fd = fd;
  86 +    unixSQLite3File->pUnused->flags = flags;
  87 +  }
  88 +}
  89 +
  90 +/*
  91 +** Destroys pFile's field that keeps track of the unused file descriptor.
  92 +*/
  93 +void chromium_sqlite3_destroy_reusable_file_handle(sqlite3_file* file) {
  94 +  unixFile* unixSQLite3File = (unixFile*)file;
  95 +  sqlite3_free(unixSQLite3File->pUnused);
  96 +}
  97 +
  98 +/*
  99  ** Open the file zPath.
 100  **
 101  ** Previously, the SQLite OS layer used three functions in place of this
 102 @@ -3893,20 +3967,13 @@ static int unixOpen(
 103         || eType==SQLITE_OPEN_TRANSIENT_DB
 104    );
 105
 106 -  memset(p, 0, sizeof(unixFile));
 107 +  chromium_sqlite3_initialize_unix_sqlite3_file(pFile);
 108
 109    if( eType==SQLITE_OPEN_MAIN_DB ){
 110 -    UnixUnusedFd *pUnused;
 111 -    pUnused = findReusableFd(zName, flags);
 112 -    if( pUnused ){
 113 -      fd = pUnused->fd;
 114 -    }else{
 115 -      pUnused = sqlite3_malloc(sizeof(*pUnused));
 116 -      if( !pUnused ){
 117 -        return SQLITE_NOMEM;
 118 -      }
 119 +    rc = chromium_sqlite3_get_reusable_file_handle(pFile, zName, flags, &fd);
 120 +    if( rc!=SQLITE_OK ){
 121 +      return rc;
 122      }
 123 -    p->pUnused = pUnused;
 124    }else if( !zName ){
 125      /* If zName is NULL, the upper layer is requesting a temp file. */
 126      assert(isDelete && !isOpenDirectory);
 127 @@ -3949,10 +4016,7 @@ static int unixOpen(
 128      *pOutFlags = flags;
 129    }
 130
 131 -  if( p->pUnused ){
 132 -    p->pUnused->fd = fd;
 133 -    p->pUnused->flags = flags;
 134 -  }
 135 +  chromium_sqlite3_update_reusable_file_handle(pFile, fd, flags);
 136
 137    if( isDelete ){
 138  #if OS_VXWORKS
 139 @@ -4028,7 +4092,7 @@ static int unixOpen(
 140    rc = fillInUnixFile(pVfs, fd, dirfd, pFile, zPath, noLock, isDelete);
 141  open_finished:
 142    if( rc!=SQLITE_OK ){
 143 -    sqlite3_free(p->pUnused);
 144 +    chromium_sqlite3_destroy_reusable_file_handle(pFile);
 145    }
 146    return rc;
 147  }
 148 diff --git src/os_win.c src/os_win.c
 149 index bc03a4b..06539d7 100644
 150 --- src/os_win.c
 151 +++ src/os_win.c
 152 @@ -1890,4 +1890,11 @@ int sqlite3_os_end(void){
 153    return SQLITE_OK;
 154  }
 155
 156 +void chromium_sqlite3_initialize_win_sqlite3_file(sqlite3_file* file, HANDLE handle) {
 157 +  winFile* winSQLite3File = (winFile*)file;
 158 +  memset(file, 0, sizeof(*file));
 159 +  winSQLite3File->pMethod = &winIoMethod;
 160 +  winSQLite3File->h = handle;
 161 +}
 162 +
 163  #endif /* SQLITE_OS_WIN */