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, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  *
  20  * Author: Alexander Larsson <alexl@redhat.com>
  21  * Author: Tor Lillqvist <tml@iki.fi>
  22  */
  23
  24 #include "config.h"
  25
  26 #include <windows.h>
  27
  28 #include <io.h>
  29
  30 #include <glib.h>
  31 #include "gioerror.h"
  32 #include "gsimpleasyncresult.h"
  33 #include "gwin32inputstream.h"
  34 #include "gcancellable.h"
  35 #include "gasynchelper.h"
  36 #include "glibintl.h"
  37
  38
  39 /**
  40  * SECTION:gwin32inputstream
  41  * @short_description: Streaming input operations for Windows file handles
  42  * @include: gio/gwin32inputstream.h
  43  * @see_also: #GInputStream
  44  *
  45  * #GWin32InputStream implements #GInputStream for reading from a
  46  * Windows file handle.
  47  *
  48  * Note that <filename>&lt;gio/gwin32inputstream.h&gt;</filename> belongs
  49  * to the Windows-specific GIO interfaces, thus you have to use the
  50  * <filename>gio-windows-2.0.pc</filename> pkg-config file when using it.
  51  */
  52
  53 enum {
  54   PROP_0,
  55   PROP_HANDLE,
  56   PROP_CLOSE_HANDLE
  57 };
  58
  59 struct _GWin32InputStreamPrivate {
  60   HANDLE handle;
  61   gboolean close_handle;
  62   gint fd;
  63 };
  64
  65 G_DEFINE_TYPE_WITH_PRIVATE (GWin32InputStream, g_win32_input_stream, G_TYPE_INPUT_STREAM)
  66
  67 static void     g_win32_input_stream_set_property (GObject              *object,
  68                                                    guint                 prop_id,
  69                                                    const GValue         *value,
  70                                                    GParamSpec           *pspec);
  71 static void     g_win32_input_stream_get_property (GObject              *object,
  72                                                    guint                 prop_id,
  73                                                    GValue               *value,
  74                                                    GParamSpec           *pspec);
  75 static gssize   g_win32_input_stream_read         (GInputStream         *stream,
  76                                                    void                 *buffer,
  77                                                    gsize                 count,
  78                                                    GCancellable         *cancellable,
  79                                                    GError              **error);
  80 static gboolean g_win32_input_stream_close        (GInputStream         *stream,
  81                                                    GCancellable         *cancellable,
  82                                                    GError              **error);
  83
  84 static void
  85 g_win32_input_stream_class_init (GWin32InputStreamClass *klass)
  86 {
  87   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  88   GInputStreamClass *stream_class = G_INPUT_STREAM_CLASS (klass);
  89
  90   gobject_class->get_property = g_win32_input_stream_get_property;
  91   gobject_class->set_property = g_win32_input_stream_set_property;
  92
  93   stream_class->read_fn = g_win32_input_stream_read;
  94   stream_class->close_fn = g_win32_input_stream_close;
  95
  96   /**
  97    * GWin32InputStream:handle:
  98    *
  99    * The handle that the stream reads from.
 100    *
 101    * Since: 2.26
 102    */
 103   g_object_class_install_property (gobject_class,
 104                                    PROP_HANDLE,
 105                                    g_param_spec_pointer ("handle",
 106                                                          P_("File handle"),
 107                                                          P_("The file handle to read from"),
 108                                                          G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
 109
 110   /**
 111    * GWin32InputStream:close-handle:
 112    *
 113    * Whether to close the file handle when the stream is closed.
 114    *
 115    * Since: 2.26
 116    */
 117   g_object_class_install_property (gobject_class,
 118                                    PROP_CLOSE_HANDLE,
 119                                    g_param_spec_boolean ("close-handle",
 120                                                          P_("Close file handle"),
 121                                                          P_("Whether to close the file handle when the stream is closed"),
 122                                                          TRUE,
 123                                                          G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
 124 }
 125
 126 static void
 127 g_win32_input_stream_set_property (GObject         *object,
 128                                    guint            prop_id,
 129                                    const GValue    *value,
 130                                    GParamSpec      *pspec)
 131 {
 132   GWin32InputStream *win32_stream;
 133
 134   win32_stream = G_WIN32_INPUT_STREAM (object);
 135
 136   switch (prop_id)
 137     {
 138     case PROP_HANDLE:
 139       win32_stream->priv->handle = g_value_get_pointer (value);
 140       break;
 141     case PROP_CLOSE_HANDLE:
 142       win32_stream->priv->close_handle = g_value_get_boolean (value);
 143       break;
 144     default:
 145       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 146       break;
 147     }
 148 }
 149
 150 static void
 151 g_win32_input_stream_get_property (GObject    *object,
 152                                    guint       prop_id,
 153                                    GValue     *value,
 154                                    GParamSpec *pspec)
 155 {
 156   GWin32InputStream *win32_stream;
 157
 158   win32_stream = G_WIN32_INPUT_STREAM (object);
 159
 160   switch (prop_id)
 161     {
 162     case PROP_HANDLE:
 163       g_value_set_pointer (value, win32_stream->priv->handle);
 164       break;
 165     case PROP_CLOSE_HANDLE:
 166       g_value_set_boolean (value, win32_stream->priv->close_handle);
 167       break;
 168     default:
 169       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 170     }
 171 }
 172
 173 static void
 174 g_win32_input_stream_init (GWin32InputStream *win32_stream)
 175 {
 176   win32_stream->priv = g_win32_input_stream_get_instance_private (win32_stream);
 177   win32_stream->priv->handle = NULL;
 178   win32_stream->priv->close_handle = TRUE;
 179   win32_stream->priv->fd = -1;
 180 }
 181
 182 /**
 183  * g_win32_input_stream_new:
 184  * @handle: a Win32 file handle
 185  * @close_handle: %TRUE to close the handle when done
 186  *
 187  * Creates a new #GWin32InputStream for the given @handle.
 188  *
 189  * If @close_handle is %TRUE, the handle will be closed
 190  * when the stream is closed.
 191  *
 192  * Note that "handle" here means a Win32 HANDLE, not a "file descriptor"
 193  * as used in the Windows C libraries.
 194  *
 195  * Returns: a new #GWin32InputStream
 196  **/
 197 GInputStream *
 198 g_win32_input_stream_new (void     *handle,
 199                           gboolean close_handle)
 200 {
 201   GWin32InputStream *stream;
 202
 203   g_return_val_if_fail (handle != NULL, NULL);
 204
 205   stream = g_object_new (G_TYPE_WIN32_INPUT_STREAM,
 206                          "handle", handle,
 207                          "close-handle", close_handle,
 208                          NULL);
 209
 210   return G_INPUT_STREAM (stream);
 211 }
 212
 213 /**
 214  * g_win32_input_stream_set_close_handle:
 215  * @stream: a #GWin32InputStream
 216  * @close_handle: %TRUE to close the handle when done
 217  *
 218  * Sets whether the handle of @stream shall be closed
 219  * when the stream is closed.
 220  *
 221  * Since: 2.26
 222  */
 223 void
 224 g_win32_input_stream_set_close_handle (GWin32InputStream *stream,
 225                                        gboolean          close_handle)
 226 {
 227   g_return_if_fail (G_IS_WIN32_INPUT_STREAM (stream));
 228
 229   close_handle = close_handle != FALSE;
 230   if (stream->priv->close_handle != close_handle)
 231     {
 232       stream->priv->close_handle = close_handle;
 233       g_object_notify (G_OBJECT (stream), "close-handle");
 234     }
 235 }
 236
 237 /**
 238  * g_win32_input_stream_get_close_handle:
 239  * @stream: a #GWin32InputStream
 240  *
 241  * Returns whether the handle of @stream will be
 242  * closed when the stream is closed.
 243  *
 244  * Return value: %TRUE if the handle is closed when done
 245  *
 246  * Since: 2.26
 247  */
 248 gboolean
 249 g_win32_input_stream_get_close_handle (GWin32InputStream *stream)
 250 {
 251   g_return_val_if_fail (G_IS_WIN32_INPUT_STREAM (stream), FALSE);
 252
 253   return stream->priv->close_handle;
 254 }
 255
 256 /**
 257  * g_win32_input_stream_get_handle:
 258  * @stream: a #GWin32InputStream
 259  *
 260  * Return the Windows file handle that the stream reads from.
 261  *
 262  * Return value: The file handle of @stream
 263  *
 264  * Since: 2.26
 265  */
 266 void *
 267 g_win32_input_stream_get_handle (GWin32InputStream *stream)
 268 {
 269   g_return_val_if_fail (G_IS_WIN32_INPUT_STREAM (stream), NULL);
 270
 271   return stream->priv->handle;
 272 }
 273
 274 static gssize
 275 g_win32_input_stream_read (GInputStream  *stream,
 276                            void          *buffer,
 277                            gsize          count,
 278                            GCancellable  *cancellable,
 279                            GError       **error)
 280 {
 281   GWin32InputStream *win32_stream;
 282   BOOL res;
 283   DWORD nbytes, nread;
 284   OVERLAPPED overlap = { 0, };
 285   gssize retval = -1;
 286
 287   win32_stream = G_WIN32_INPUT_STREAM (stream);
 288
 289   if (g_cancellable_set_error_if_cancelled (cancellable, error))
 290     return -1;
 291
 292   if (count > G_MAXINT)
 293     nbytes = G_MAXINT;
 294   else
 295     nbytes = count;
 296
 297   overlap.hEvent = CreateEvent (NULL, FALSE, FALSE, NULL);
 298   g_return_val_if_fail (overlap.hEvent != NULL, -1);
 299
 300   res = ReadFile (win32_stream->priv->handle, buffer, nbytes, &nread, &overlap);
 301   if (res)
 302     retval = nread;
 303   else
 304     {
 305       int errsv = GetLastError ();
 306
 307       if (errsv == ERROR_IO_PENDING &&
 308           _g_win32_overlap_wait_result (win32_stream->priv->handle,
 309                                         &overlap, &nread, cancellable))
 310         {
 311           retval = nread;
 312           goto end;
 313         }
 314
 315       if (g_cancellable_set_error_if_cancelled (cancellable, error))
 316         goto end;
 317
 318       errsv = GetLastError ();
 319       if (errsv == ERROR_MORE_DATA)
 320         {
 321           /* If a named pipe is being read in message mode and the
 322            * next message is longer than the nNumberOfBytesToRead
 323            * parameter specifies, ReadFile returns FALSE and
 324            * GetLastError returns ERROR_MORE_DATA */
 325           retval = nread;
 326           goto end;
 327         }
 328       else if (errsv == ERROR_HANDLE_EOF ||
 329                errsv == ERROR_BROKEN_PIPE)
 330         {
 331           /* TODO: the other end of a pipe may call the WriteFile
 332            * function with nNumberOfBytesToWrite set to zero. In this
 333            * case, it's not possible for the caller to know if it's
 334            * broken pipe or a read of 0. Perhaps we should add a
 335            * is_broken flag for this win32 case.. */
 336           retval = 0;
 337         }
 338       else
 339         {
 340           gchar *emsg;
 341
 342           emsg = g_win32_error_message (errsv);
 343           g_set_error (error, G_IO_ERROR,
 344                        g_io_error_from_win32_error (errsv),
 345                        _("Error reading from handle: %s"),
 346                        emsg);
 347           g_free (emsg);
 348         }
 349     }
 350
 351 end:
 352   CloseHandle (overlap.hEvent);
 353   return retval;
 354 }
 355
 356 static gboolean
 357 g_win32_input_stream_close (GInputStream  *stream,
 358                            GCancellable  *cancellable,
 359                            GError       **error)
 360 {
 361   GWin32InputStream *win32_stream;
 362   BOOL res;
 363
 364   win32_stream = G_WIN32_INPUT_STREAM (stream);
 365
 366   if (!win32_stream->priv->close_handle)
 367     return TRUE;
 368
 369   if (win32_stream->priv->fd != -1)
 370     {
 371       if (close (win32_stream->priv->fd) < 0)
 372         {
 373           g_set_error_literal (error, G_IO_ERROR,
 374                                g_io_error_from_errno (errno),
 375                                g_strerror (errno));
 376           return FALSE;
 377         }
 378     }
 379   else
 380     {
 381       res = CloseHandle (win32_stream->priv->handle);
 382       if (!res)
 383         {
 384           int errsv = GetLastError ();
 385           gchar *emsg = g_win32_error_message (errsv);
 386
 387           g_set_error (error, G_IO_ERROR,
 388                        g_io_error_from_win32_error (errsv),
 389                        _("Error closing handle: %s"),
 390                        emsg);
 391           g_free (emsg);
 392           return FALSE;
 393         }
 394     }
 395
 396   return TRUE;
 397 }
 398
 399 GInputStream *
 400 g_win32_input_stream_new_from_fd (gint      fd,
 401                                   gboolean  close_fd)
 402 {
 403   GWin32InputStream *win32_stream;
 404
 405   win32_stream = G_WIN32_INPUT_STREAM (g_win32_input_stream_new ((HANDLE) _get_osfhandle (fd), close_fd));
 406   win32_stream->priv->fd = fd;
 407
 408   return (GInputStream*)win32_stream;
 409 }