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 "giowin32-priv.h"
  35 #include "gcancellable.h"
  36 #include "gasynchelper.h"
  37 #include "glibintl.h"
  38
  39
  40 /**
  41  * SECTION:gwin32inputstream
  42  * @short_description: Streaming input operations for Windows file handles
  43  * @include: gio/gwin32inputstream.h
  44  * @see_also: #GInputStream
  45  *
  46  * #GWin32InputStream implements #GInputStream for reading from a
  47  * Windows file handle.
  48  *
  49  * Note that <filename>&lt;gio/gwin32inputstream.h&gt;</filename> belongs
  50  * to the Windows-specific GIO interfaces, thus you have to use the
  51  * <filename>gio-windows-2.0.pc</filename> pkg-config file when using it.
  52  */
  53
  54 enum {
  55   PROP_0,
  56   PROP_HANDLE,
  57   PROP_CLOSE_HANDLE
  58 };
  59
  60 struct _GWin32InputStreamPrivate {
  61   HANDLE handle;
  62   gboolean close_handle;
  63   gint fd;
  64 };
  65
  66 G_DEFINE_TYPE_WITH_PRIVATE (GWin32InputStream, g_win32_input_stream, G_TYPE_INPUT_STREAM)
  67
  68 static void     g_win32_input_stream_set_property (GObject              *object,
  69                                                    guint                 prop_id,
  70                                                    const GValue         *value,
  71                                                    GParamSpec           *pspec);
  72 static void     g_win32_input_stream_get_property (GObject              *object,
  73                                                    guint                 prop_id,
  74                                                    GValue               *value,
  75                                                    GParamSpec           *pspec);
  76 static gssize   g_win32_input_stream_read         (GInputStream         *stream,
  77                                                    void                 *buffer,
  78                                                    gsize                 count,
  79                                                    GCancellable         *cancellable,
  80                                                    GError              **error);
  81 static gboolean g_win32_input_stream_close        (GInputStream         *stream,
  82                                                    GCancellable         *cancellable,
  83                                                    GError              **error);
  84
  85 static void
  86 g_win32_input_stream_class_init (GWin32InputStreamClass *klass)
  87 {
  88   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
  89   GInputStreamClass *stream_class = G_INPUT_STREAM_CLASS (klass);
  90
  91   gobject_class->get_property = g_win32_input_stream_get_property;
  92   gobject_class->set_property = g_win32_input_stream_set_property;
  93
  94   stream_class->read_fn = g_win32_input_stream_read;
  95   stream_class->close_fn = g_win32_input_stream_close;
  96
  97   /**
  98    * GWin32InputStream:handle:
  99    *
 100    * The handle that the stream reads from.
 101    *
 102    * Since: 2.26
 103    */
 104   g_object_class_install_property (gobject_class,
 105                                    PROP_HANDLE,
 106                                    g_param_spec_pointer ("handle",
 107                                                          P_("File handle"),
 108                                                          P_("The file handle to read from"),
 109                                                          G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
 110
 111   /**
 112    * GWin32InputStream:close-handle:
 113    *
 114    * Whether to close the file handle when the stream is closed.
 115    *
 116    * Since: 2.26
 117    */
 118   g_object_class_install_property (gobject_class,
 119                                    PROP_CLOSE_HANDLE,
 120                                    g_param_spec_boolean ("close-handle",
 121                                                          P_("Close file handle"),
 122                                                          P_("Whether to close the file handle when the stream is closed"),
 123                                                          TRUE,
 124                                                          G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_STATIC_NAME | G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB));
 125 }
 126
 127 static void
 128 g_win32_input_stream_set_property (GObject         *object,
 129                                    guint            prop_id,
 130                                    const GValue    *value,
 131                                    GParamSpec      *pspec)
 132 {
 133   GWin32InputStream *win32_stream;
 134
 135   win32_stream = G_WIN32_INPUT_STREAM (object);
 136
 137   switch (prop_id)
 138     {
 139     case PROP_HANDLE:
 140       win32_stream->priv->handle = g_value_get_pointer (value);
 141       break;
 142     case PROP_CLOSE_HANDLE:
 143       win32_stream->priv->close_handle = g_value_get_boolean (value);
 144       break;
 145     default:
 146       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 147       break;
 148     }
 149 }
 150
 151 static void
 152 g_win32_input_stream_get_property (GObject    *object,
 153                                    guint       prop_id,
 154                                    GValue     *value,
 155                                    GParamSpec *pspec)
 156 {
 157   GWin32InputStream *win32_stream;
 158
 159   win32_stream = G_WIN32_INPUT_STREAM (object);
 160
 161   switch (prop_id)
 162     {
 163     case PROP_HANDLE:
 164       g_value_set_pointer (value, win32_stream->priv->handle);
 165       break;
 166     case PROP_CLOSE_HANDLE:
 167       g_value_set_boolean (value, win32_stream->priv->close_handle);
 168       break;
 169     default:
 170       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 171     }
 172 }
 173
 174 static void
 175 g_win32_input_stream_init (GWin32InputStream *win32_stream)
 176 {
 177   win32_stream->priv = g_win32_input_stream_get_instance_private (win32_stream);
 178   win32_stream->priv->handle = NULL;
 179   win32_stream->priv->close_handle = TRUE;
 180   win32_stream->priv->fd = -1;
 181 }
 182
 183 /**
 184  * g_win32_input_stream_new:
 185  * @handle: a Win32 file handle
 186  * @close_handle: %TRUE to close the handle when done
 187  *
 188  * Creates a new #GWin32InputStream for the given @handle.
 189  *
 190  * If @close_handle is %TRUE, the handle will be closed
 191  * when the stream is closed.
 192  *
 193  * Note that "handle" here means a Win32 HANDLE, not a "file descriptor"
 194  * as used in the Windows C libraries.
 195  *
 196  * Returns: a new #GWin32InputStream
 197  **/
 198 GInputStream *
 199 g_win32_input_stream_new (void     *handle,
 200                           gboolean close_handle)
 201 {
 202   GWin32InputStream *stream;
 203
 204   g_return_val_if_fail (handle != NULL, NULL);
 205
 206   stream = g_object_new (G_TYPE_WIN32_INPUT_STREAM,
 207                          "handle", handle,
 208                          "close-handle", close_handle,
 209                          NULL);
 210
 211   return G_INPUT_STREAM (stream);
 212 }
 213
 214 /**
 215  * g_win32_input_stream_set_close_handle:
 216  * @stream: a #GWin32InputStream
 217  * @close_handle: %TRUE to close the handle when done
 218  *
 219  * Sets whether the handle of @stream shall be closed
 220  * when the stream is closed.
 221  *
 222  * Since: 2.26
 223  */
 224 void
 225 g_win32_input_stream_set_close_handle (GWin32InputStream *stream,
 226                                        gboolean          close_handle)
 227 {
 228   g_return_if_fail (G_IS_WIN32_INPUT_STREAM (stream));
 229
 230   close_handle = close_handle != FALSE;
 231   if (stream->priv->close_handle != close_handle)
 232     {
 233       stream->priv->close_handle = close_handle;
 234       g_object_notify (G_OBJECT (stream), "close-handle");
 235     }
 236 }
 237
 238 /**
 239  * g_win32_input_stream_get_close_handle:
 240  * @stream: a #GWin32InputStream
 241  *
 242  * Returns whether the handle of @stream will be
 243  * closed when the stream is closed.
 244  *
 245  * Return value: %TRUE if the handle is closed when done
 246  *
 247  * Since: 2.26
 248  */
 249 gboolean
 250 g_win32_input_stream_get_close_handle (GWin32InputStream *stream)
 251 {
 252   g_return_val_if_fail (G_IS_WIN32_INPUT_STREAM (stream), FALSE);
 253
 254   return stream->priv->close_handle;
 255 }
 256
 257 /**
 258  * g_win32_input_stream_get_handle:
 259  * @stream: a #GWin32InputStream
 260  *
 261  * Return the Windows file handle that the stream reads from.
 262  *
 263  * Return value: The file handle of @stream
 264  *
 265  * Since: 2.26
 266  */
 267 void *
 268 g_win32_input_stream_get_handle (GWin32InputStream *stream)
 269 {
 270   g_return_val_if_fail (G_IS_WIN32_INPUT_STREAM (stream), NULL);
 271
 272   return stream->priv->handle;
 273 }
 274
 275 static gssize
 276 g_win32_input_stream_read (GInputStream  *stream,
 277                            void          *buffer,
 278                            gsize          count,
 279                            GCancellable  *cancellable,
 280                            GError       **error)
 281 {
 282   GWin32InputStream *win32_stream;
 283   BOOL res;
 284   DWORD nbytes, nread;
 285   OVERLAPPED overlap = { 0, };
 286   gssize retval = -1;
 287
 288   win32_stream = G_WIN32_INPUT_STREAM (stream);
 289
 290   if (g_cancellable_set_error_if_cancelled (cancellable, error))
 291     return -1;
 292
 293   if (count > G_MAXINT)
 294     nbytes = G_MAXINT;
 295   else
 296     nbytes = count;
 297
 298   overlap.hEvent = CreateEvent (NULL, FALSE, FALSE, NULL);
 299   g_return_val_if_fail (overlap.hEvent != NULL, -1);
 300
 301   res = ReadFile (win32_stream->priv->handle, buffer, nbytes, &nread, &overlap);
 302   if (res)
 303     retval = nread;
 304   else
 305     {
 306       int errsv = GetLastError ();
 307
 308       if (errsv == ERROR_IO_PENDING &&
 309           _g_win32_overlap_wait_result (win32_stream->priv->handle,
 310                                         &overlap, &nread, cancellable))
 311         {
 312           retval = nread;
 313           goto end;
 314         }
 315
 316       if (g_cancellable_set_error_if_cancelled (cancellable, error))
 317         goto end;
 318
 319       errsv = GetLastError ();
 320       if (errsv == ERROR_MORE_DATA)
 321         {
 322           /* If a named pipe is being read in message mode and the
 323            * next message is longer than the nNumberOfBytesToRead
 324            * parameter specifies, ReadFile returns FALSE and
 325            * GetLastError returns ERROR_MORE_DATA */
 326           retval = nread;
 327           goto end;
 328         }
 329       else if (errsv == ERROR_HANDLE_EOF ||
 330                errsv == ERROR_BROKEN_PIPE)
 331         {
 332           /* TODO: the other end of a pipe may call the WriteFile
 333            * function with nNumberOfBytesToWrite set to zero. In this
 334            * case, it's not possible for the caller to know if it's
 335            * broken pipe or a read of 0. Perhaps we should add a
 336            * is_broken flag for this win32 case.. */
 337           retval = 0;
 338         }
 339       else
 340         {
 341           gchar *emsg;
 342
 343           emsg = g_win32_error_message (errsv);
 344           g_set_error (error, G_IO_ERROR,
 345                        g_io_error_from_win32_error (errsv),
 346                        _("Error reading from handle: %s"),
 347                        emsg);
 348           g_free (emsg);
 349         }
 350     }
 351
 352 end:
 353   CloseHandle (overlap.hEvent);
 354   return retval;
 355 }
 356
 357 static gboolean
 358 g_win32_input_stream_close (GInputStream  *stream,
 359                            GCancellable  *cancellable,
 360                            GError       **error)
 361 {
 362   GWin32InputStream *win32_stream;
 363   BOOL res;
 364
 365   win32_stream = G_WIN32_INPUT_STREAM (stream);
 366
 367   if (!win32_stream->priv->close_handle)
 368     return TRUE;
 369
 370   if (win32_stream->priv->fd != -1)
 371     {
 372       if (close (win32_stream->priv->fd) < 0)
 373         {
 374           g_set_error_literal (error, G_IO_ERROR,
 375                                g_io_error_from_errno (errno),
 376                                g_strerror (errno));
 377           return FALSE;
 378         }
 379     }
 380   else
 381     {
 382       res = CloseHandle (win32_stream->priv->handle);
 383       if (!res)
 384         {
 385           int errsv = GetLastError ();
 386           gchar *emsg = g_win32_error_message (errsv);
 387
 388           g_set_error (error, G_IO_ERROR,
 389                        g_io_error_from_win32_error (errsv),
 390                        _("Error closing handle: %s"),
 391                        emsg);
 392           g_free (emsg);
 393           return FALSE;
 394         }
 395     }
 396
 397   return TRUE;
 398 }
 399
 400 GInputStream *
 401 g_win32_input_stream_new_from_fd (gint      fd,
 402                                   gboolean  close_fd)
 403 {
 404   GWin32InputStream *win32_stream;
 405
 406   win32_stream = G_WIN32_INPUT_STREAM (g_win32_input_stream_new ((HANDLE) _get_osfhandle (fd), close_fd));
 407   win32_stream->priv->fd = fd;
 408
 409   return (GInputStream*)win32_stream;
 410 }