gio/gwin32inputstream.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2006-2010 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  17  *
  18  * Author: Alexander Larsson <alexl@redhat.com>
  19  * Author: Tor Lillqvist <tml@iki.fi>
  20  */
  21
  22 #include "config.h"
  23
  24 #include <windows.h>
  25
  26 #include <io.h>
  27
  28 #include <glib.h>
  29 #include "gioerror.h"
  30 #include "gsimpleasyncresult.h"
  31 #include "gwin32inputstream.h"
  32 #include "giowin32-priv.h"
  33 #include "gcancellable.h"
  34 #include "gasynchelper.h"
  35 #include "glibintl.h"
  36
  37
  38 /**
  39  * SECTION:gwin32inputstream
  40  * @short_description: Streaming input operations for Windows file handles
  41  * @include: gio/gwin32inputstream.h
  42  * @see_also: #GInputStream
  43  *
  44  * #GWin32InputStream implements #GInputStream for reading from a
  45  * Windows file handle.
  46  *
  47  * Note that `<gio/gwin32inputstream.h>` belongs to the Windows-specific GIO
  48  * interfaces, thus you have to use the `gio-windows-2.0.pc` pkg-config file
  49  * when using it.
  50  */
  51
  52 enum {
  53   PROP_0,
  54   PROP_HANDLE,
  55   PROP_CLOSE_HANDLE
  56 };
  57
  58 struct _GWin32InputStreamPrivate {
  59   HANDLE handle;
  60   gboolean close_handle;
  61   gint fd;
  62 };
  63
  64 G_DEFINE_TYPE_WITH_PRIVATE (GWin32InputStream, g_win32_input_stream, G_TYPE_INPUT_STREAM)
  65
  66 static void     g_win32_input_stream_set_property (GObject              *object,
  67                                                    guint                 prop_id,
  68                                                    const GValue         *value,
  69                                                    GParamSpec           *pspec);
  70 static void     g_win32_input_stream_get_property (GObject              *object,
  71                                                    guint                 prop_id,
  72                                                    GValue               *value,
  73                                                    GParamSpec           *pspec);
  74 static gssize   g_win32_input_stream_read         (GInputStream         *stream,
  75                                                    void                 *buffer,
  76                                                    gsize                 count,
  77                                                    GCancellable         *cancellable,
  78                                                    GError              **error);
  79 static gboolean g_win32_input_stream_close        (GInputStream         *stream,
  80                                                    GCancellable         *cancellable,
  81                                                    GError              **error);
  82
  83 static void
  84 g_win32_input_stream_class_init (GWin32InputStreamClass *klass)
  85 {
  86   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  87   GInputStreamClass *stream_class = G_INPUT_STREAM_CLASS (klass);
  88
  89   gobject_class->get_property = g_win32_input_stream_get_property;
  90   gobject_class->set_property = g_win32_input_stream_set_property;
  91
  92   stream_class->read_fn = g_win32_input_stream_read;
  93   stream_class->close_fn = g_win32_input_stream_close;
  94
  95   /**
  96    * GWin32InputStream:handle:
  97    *
  98    * The handle that the stream reads from.
  99    *
 100    * Since: 2.26
 101    */
 102   g_object_class_install_property (gobject_class,
 103                                    PROP_HANDLE,
 104                                    g_param_spec_pointer ("handle",
 105                                                          P_("File handle"),
 106                                                          P_("The file handle to read from"),
 107                                                          G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
 108
 109   /**
 110    * GWin32InputStream:close-handle:
 111    *
 112    * Whether to close the file handle when the stream is closed.
 113    *
 114    * Since: 2.26
 115    */
 116   g_object_class_install_property (gobject_class,
 117                                    PROP_CLOSE_HANDLE,
 118                                    g_param_spec_boolean ("close-handle",
 119                                                          P_("Close file handle"),
 120                                                          P_("Whether to close the file handle when the stream is closed"),
 121                                                          TRUE,
 122                                                          G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
 123 }
 124
 125 static void
 126 g_win32_input_stream_set_property (GObject         *object,
 127                                    guint            prop_id,
 128                                    const GValue    *value,
 129                                    GParamSpec      *pspec)
 130 {
 131   GWin32InputStream *win32_stream;
 132
 133   win32_stream = G_WIN32_INPUT_STREAM (object);
 134
 135   switch (prop_id)
 136     {
 137     case PROP_HANDLE:
 138       win32_stream->priv->handle = g_value_get_pointer (value);
 139       break;
 140     case PROP_CLOSE_HANDLE:
 141       win32_stream->priv->close_handle = g_value_get_boolean (value);
 142       break;
 143     default:
 144       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 145       break;
 146     }
 147 }
 148
 149 static void
 150 g_win32_input_stream_get_property (GObject    *object,
 151                                    guint       prop_id,
 152                                    GValue     *value,
 153                                    GParamSpec *pspec)
 154 {
 155   GWin32InputStream *win32_stream;
 156
 157   win32_stream = G_WIN32_INPUT_STREAM (object);
 158
 159   switch (prop_id)
 160     {
 161     case PROP_HANDLE:
 162       g_value_set_pointer (value, win32_stream->priv->handle);
 163       break;
 164     case PROP_CLOSE_HANDLE:
 165       g_value_set_boolean (value, win32_stream->priv->close_handle);
 166       break;
 167     default:
 168       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 169     }
 170 }
 171
 172 static void
 173 g_win32_input_stream_init (GWin32InputStream *win32_stream)
 174 {
 175   win32_stream->priv = g_win32_input_stream_get_instance_private (win32_stream);
 176   win32_stream->priv->handle = NULL;
 177   win32_stream->priv->close_handle = TRUE;
 178   win32_stream->priv->fd = -1;
 179 }
 180
 181 /**
 182  * g_win32_input_stream_new:
 183  * @handle: a Win32 file handle
 184  * @close_handle: %TRUE to close the handle when done
 185  *
 186  * Creates a new #GWin32InputStream for the given @handle.
 187  *
 188  * If @close_handle is %TRUE, the handle will be closed
 189  * when the stream is closed.
 190  *
 191  * Note that "handle" here means a Win32 HANDLE, not a "file descriptor"
 192  * as used in the Windows C libraries.
 193  *
 194  * Returns: a new #GWin32InputStream
 195  **/
 196 GInputStream *
 197 g_win32_input_stream_new (void     *handle,
 198                           gboolean close_handle)
 199 {
 200   GWin32InputStream *stream;
 201
 202   g_return_val_if_fail (handle != NULL, NULL);
 203
 204   stream = g_object_new (G_TYPE_WIN32_INPUT_STREAM,
 205                          "handle", handle,
 206                          "close-handle", close_handle,
 207                          NULL);
 208
 209   return G_INPUT_STREAM (stream);
 210 }
 211
 212 /**
 213  * g_win32_input_stream_set_close_handle:
 214  * @stream: a #GWin32InputStream
 215  * @close_handle: %TRUE to close the handle when done
 216  *
 217  * Sets whether the handle of @stream shall be closed
 218  * when the stream is closed.
 219  *
 220  * Since: 2.26
 221  */
 222 void
 223 g_win32_input_stream_set_close_handle (GWin32InputStream *stream,
 224                                        gboolean          close_handle)
 225 {
 226   g_return_if_fail (G_IS_WIN32_INPUT_STREAM (stream));
 227
 228   close_handle = close_handle != FALSE;
 229   if (stream->priv->close_handle != close_handle)
 230     {
 231       stream->priv->close_handle = close_handle;
 232       g_object_notify (G_OBJECT (stream), "close-handle");
 233     }
 234 }
 235
 236 /**
 237  * g_win32_input_stream_get_close_handle:
 238  * @stream: a #GWin32InputStream
 239  *
 240  * Returns whether the handle of @stream will be
 241  * closed when the stream is closed.
 242  *
 243  * Returns: %TRUE if the handle is closed when done
 244  *
 245  * Since: 2.26
 246  */
 247 gboolean
 248 g_win32_input_stream_get_close_handle (GWin32InputStream *stream)
 249 {
 250   g_return_val_if_fail (G_IS_WIN32_INPUT_STREAM (stream), FALSE);
 251
 252   return stream->priv->close_handle;
 253 }
 254
 255 /**
 256  * g_win32_input_stream_get_handle:
 257  * @stream: a #GWin32InputStream
 258  *
 259  * Return the Windows file handle that the stream reads from.
 260  *
 261  * Returns: The file handle of @stream
 262  *
 263  * Since: 2.26
 264  */
 265 void *
 266 g_win32_input_stream_get_handle (GWin32InputStream *stream)
 267 {
 268   g_return_val_if_fail (G_IS_WIN32_INPUT_STREAM (stream), NULL);
 269
 270   return stream->priv->handle;
 271 }
 272
 273 static gssize
 274 g_win32_input_stream_read (GInputStream  *stream,
 275                            void          *buffer,
 276                            gsize          count,
 277                            GCancellable  *cancellable,
 278                            GError       **error)
 279 {
 280   GWin32InputStream *win32_stream;
 281   BOOL res;
 282   DWORD nbytes, nread;
 283   OVERLAPPED overlap = { 0, };
 284   gssize retval = -1;
 285
 286   win32_stream = G_WIN32_INPUT_STREAM (stream);
 287
 288   if (g_cancellable_set_error_if_cancelled (cancellable, error))
 289     return -1;
 290
 291   if (count > G_MAXINT)
 292     nbytes = G_MAXINT;
 293   else
 294     nbytes = count;
 295
 296   overlap.hEvent = CreateEvent (NULL, FALSE, FALSE, NULL);
 297   g_return_val_if_fail (overlap.hEvent != NULL, -1);
 298
 299   res = ReadFile (win32_stream->priv->handle, buffer, nbytes, &nread, &overlap);
 300   if (res)
 301     retval = nread;
 302   else
 303     {
 304       int errsv = GetLastError ();
 305
 306       if (errsv == ERROR_IO_PENDING &&
 307           _g_win32_overlap_wait_result (win32_stream->priv->handle,
 308                                         &overlap, &nread, cancellable))
 309         {
 310           retval = nread;
 311           goto end;
 312         }
 313
 314       if (g_cancellable_set_error_if_cancelled (cancellable, error))
 315         goto end;
 316
 317       errsv = GetLastError ();
 318       if (errsv == ERROR_MORE_DATA)
 319         {
 320           /* If a named pipe is being read in message mode and the
 321            * next message is longer than the nNumberOfBytesToRead
 322            * parameter specifies, ReadFile returns FALSE and
 323            * GetLastError returns ERROR_MORE_DATA */
 324           retval = nread;
 325           goto end;
 326         }
 327       else if (errsv == ERROR_HANDLE_EOF ||
 328                errsv == ERROR_BROKEN_PIPE)
 329         {
 330           /* TODO: the other end of a pipe may call the WriteFile
 331            * function with nNumberOfBytesToWrite set to zero. In this
 332            * case, it's not possible for the caller to know if it's
 333            * broken pipe or a read of 0. Perhaps we should add a
 334            * is_broken flag for this win32 case.. */
 335           retval = 0;
 336         }
 337       else
 338         {
 339           gchar *emsg;
 340
 341           emsg = g_win32_error_message (errsv);
 342           g_set_error (error, G_IO_ERROR,
 343                        g_io_error_from_win32_error (errsv),
 344                        _("Error reading from handle: %s"),
 345                        emsg);
 346           g_free (emsg);
 347         }
 348     }
 349
 350 end:
 351   CloseHandle (overlap.hEvent);
 352   return retval;
 353 }
 354
 355 static gboolean
 356 g_win32_input_stream_close (GInputStream  *stream,
 357                            GCancellable  *cancellable,
 358                            GError       **error)
 359 {
 360   GWin32InputStream *win32_stream;
 361   BOOL res;
 362
 363   win32_stream = G_WIN32_INPUT_STREAM (stream);
 364
 365   if (!win32_stream->priv->close_handle)
 366     return TRUE;
 367
 368   if (win32_stream->priv->fd != -1)
 369     {
 370       if (close (win32_stream->priv->fd) < 0)
 371         {
 372           g_set_error_literal (error, G_IO_ERROR,
 373                                g_io_error_from_errno (errno),
 374                                g_strerror (errno));
 375           return FALSE;
 376         }
 377     }
 378   else
 379     {
 380       res = CloseHandle (win32_stream->priv->handle);
 381       if (!res)
 382         {
 383           int errsv = GetLastError ();
 384           gchar *emsg = g_win32_error_message (errsv);
 385
 386           g_set_error (error, G_IO_ERROR,
 387                        g_io_error_from_win32_error (errsv),
 388                        _("Error closing handle: %s"),
 389                        emsg);
 390           g_free (emsg);
 391           return FALSE;
 392         }
 393     }
 394
 395   return TRUE;
 396 }
 397
 398 GInputStream *
 399 g_win32_input_stream_new_from_fd (gint      fd,
 400                                   gboolean  close_fd)
 401 {
 402   GWin32InputStream *win32_stream;
 403
 404   win32_stream = G_WIN32_INPUT_STREAM (g_win32_input_stream_new ((HANDLE) _get_osfhandle (fd), close_fd));
 405   win32_stream->priv->fd = fd;
 406
 407   return (GInputStream*)win32_stream;
 408 }