gio/goutputstream.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2006-2007 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  */
  22
  23 #include "config.h"
  24 #include "goutputstream.h"
  25 #include "gcancellable.h"
  26 #include "gasyncresult.h"
  27 #include "gsimpleasyncresult.h"
  28 #include "ginputstream.h"
  29 #include "gioerror.h"
  30 #include "glibintl.h"
  31
  32
  33 /**
  34  * SECTION:goutputstream
  35  * @short_description: Base class for implementing streaming output
  36  * @include: gio/gio.h
  37  *
  38  * GOutputStream has functions to write to a stream (g_output_stream_write()),
  39  * to close a stream (g_output_stream_close()) and to flush pending writes
  40  * (g_output_stream_flush()).
  41  *
  42  * To copy the content of an input stream to an output stream without
  43  * manually handling the reads and writes, use g_output_stream_splice().
  44  *
  45  * All of these functions have async variants too.
  46  **/
  47
  48 G_DEFINE_ABSTRACT_TYPE (GOutputStream, g_output_stream, G_TYPE_OBJECT);
  49
  50 struct _GOutputStreamPrivate {
  51   guint closed : 1;
  52   guint pending : 1;
  53   guint closing : 1;
  54   GAsyncReadyCallback outstanding_callback;
  55 };
  56
  57 static gssize   g_output_stream_real_splice        (GOutputStream             *stream,
  58                                                     GInputStream              *source,
  59                                                     GOutputStreamSpliceFlags   flags,
  60                                                     GCancellable              *cancellable,
  61                                                     GError                   **error);
  62 static void     g_output_stream_real_write_async   (GOutputStream             *stream,
  63                                                     const void                *buffer,
  64                                                     gsize                      count,
  65                                                     int                        io_priority,
  66                                                     GCancellable              *cancellable,
  67                                                     GAsyncReadyCallback        callback,
  68                                                     gpointer                   data);
  69 static gssize   g_output_stream_real_write_finish  (GOutputStream             *stream,
  70                                                     GAsyncResult              *result,
  71                                                     GError                   **error);
  72 static void     g_output_stream_real_splice_async  (GOutputStream             *stream,
  73                                                     GInputStream              *source,
  74                                                     GOutputStreamSpliceFlags   flags,
  75                                                     int                        io_priority,
  76                                                     GCancellable              *cancellable,
  77                                                     GAsyncReadyCallback        callback,
  78                                                     gpointer                   data);
  79 static gssize   g_output_stream_real_splice_finish (GOutputStream             *stream,
  80                                                     GAsyncResult              *result,
  81                                                     GError                   **error);
  82 static void     g_output_stream_real_flush_async   (GOutputStream             *stream,
  83                                                     int                        io_priority,
  84                                                     GCancellable              *cancellable,
  85                                                     GAsyncReadyCallback        callback,
  86                                                     gpointer                   data);
  87 static gboolean g_output_stream_real_flush_finish  (GOutputStream             *stream,
  88                                                     GAsyncResult              *result,
  89                                                     GError                   **error);
  90 static void     g_output_stream_real_close_async   (GOutputStream             *stream,
  91                                                     int                        io_priority,
  92                                                     GCancellable              *cancellable,
  93                                                     GAsyncReadyCallback        callback,
  94                                                     gpointer                   data);
  95 static gboolean g_output_stream_real_close_finish  (GOutputStream             *stream,
  96                                                     GAsyncResult              *result,
  97                                                     GError                   **error);
  98
  99 static void
 100 g_output_stream_finalize (GObject *object)
 101 {
 102   G_OBJECT_CLASS (g_output_stream_parent_class)->finalize (object);
 103 }
 104
 105 static void
 106 g_output_stream_dispose (GObject *object)
 107 {
 108   GOutputStream *stream;
 109
 110   stream = G_OUTPUT_STREAM (object);
 111
 112   if (!stream->priv->closed)
 113     g_output_stream_close (stream, NULL, NULL);
 114
 115   G_OBJECT_CLASS (g_output_stream_parent_class)->dispose (object);
 116 }
 117
 118 static void
 119 g_output_stream_class_init (GOutputStreamClass *klass)
 120 {
 121   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 122
 123   g_type_class_add_private (klass, sizeof (GOutputStreamPrivate));
 124
 125   gobject_class->finalize = g_output_stream_finalize;
 126   gobject_class->dispose = g_output_stream_dispose;
 127
 128   klass->splice = g_output_stream_real_splice;
 129
 130   klass->write_async = g_output_stream_real_write_async;
 131   klass->write_finish = g_output_stream_real_write_finish;
 132   klass->splice_async = g_output_stream_real_splice_async;
 133   klass->splice_finish = g_output_stream_real_splice_finish;
 134   klass->flush_async = g_output_stream_real_flush_async;
 135   klass->flush_finish = g_output_stream_real_flush_finish;
 136   klass->close_async = g_output_stream_real_close_async;
 137   klass->close_finish = g_output_stream_real_close_finish;
 138 }
 139
 140 static void
 141 g_output_stream_init (GOutputStream *stream)
 142 {
 143   stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream,
 144                                               G_TYPE_OUTPUT_STREAM,
 145                                               GOutputStreamPrivate);
 146 }
 147
 148 /**
 149  * g_output_stream_write:
 150  * @stream: a #GOutputStream.
 151  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 152  * @count: the number of bytes to write
 153  * @cancellable: optional cancellable object
 154  * @error: location to store the error occuring, or %NULL to ignore
 155  *
 156  * Tries to write @count bytes from @buffer into the stream. Will block
 157  * during the operation.
 158  *
 159  * If count is 0, returns 0 and does nothing. A value of @count
 160  * larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
 161  *
 162  * On success, the number of bytes written to the stream is returned.
 163  * It is not an error if this is not the same as the requested size, as it
 164  * can happen e.g. on a partial I/O error, or if there is not enough
 165  * storage in the stream. All writes block until at least one byte
 166  * is written or an error occurs; 0 is never returned (unless
 167  * @count is 0).
 168  *
 169  * If @cancellable is not NULL, then the operation can be cancelled by
 170  * triggering the cancellable object from another thread. If the operation
 171  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an
 172  * operation was partially finished when the operation was cancelled the
 173  * partial result will be returned, without an error.
 174  *
 175  * On error -1 is returned and @error is set accordingly.
 176  *
 177  * Return value: Number of bytes written, or -1 on error
 178  **/
 179 gssize
 180 g_output_stream_write (GOutputStream  *stream,
 181                        const void     *buffer,
 182                        gsize           count,
 183                        GCancellable   *cancellable,
 184                        GError        **error)
 185 {
 186   GOutputStreamClass *class;
 187   gssize res;
 188
 189   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 190   g_return_val_if_fail (buffer != NULL, 0);
 191
 192   if (count == 0)
 193     return 0;
 194
 195   if (((gssize) count) < 0)
 196     {
 197       g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 198                    _("Too large count value passed to %s"), G_STRFUNC);
 199       return -1;
 200     }
 201
 202   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 203
 204   if (class->write_fn == NULL)
 205     {
 206       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 207                            _("Output stream doesn't implement write"));
 208       return -1;
 209     }
 210
 211   if (!g_output_stream_set_pending (stream, error))
 212     return -1;
 213
 214   if (cancellable)
 215     g_cancellable_push_current (cancellable);
 216
 217   res = class->write_fn (stream, buffer, count, cancellable, error);
 218
 219   if (cancellable)
 220     g_cancellable_pop_current (cancellable);
 221
 222   g_output_stream_clear_pending (stream);
 223
 224   return res;
 225 }
 226
 227 /**
 228  * g_output_stream_write_all:
 229  * @stream: a #GOutputStream.
 230  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 231  * @count: the number of bytes to write
 232  * @bytes_written: location to store the number of bytes that was
 233  *     written to the stream
 234  * @cancellable: optional #GCancellable object, %NULL to ignore.
 235  * @error: location to store the error occuring, or %NULL to ignore
 236  *
 237  * Tries to write @count bytes from @buffer into the stream. Will block
 238  * during the operation.
 239  *
 240  * This function is similar to g_output_stream_write(), except it tries to
 241  * write as many bytes as requested, only stopping on an error.
 242  *
 243  * On a successful write of @count bytes, %TRUE is returned, and @bytes_written
 244  * is set to @count.
 245  *
 246  * If there is an error during the operation FALSE is returned and @error
 247  * is set to indicate the error status, @bytes_written is updated to contain
 248  * the number of bytes written into the stream before the error occurred.
 249  *
 250  * Return value: %TRUE on success, %FALSE if there was an error
 251  **/
 252 gboolean
 253 g_output_stream_write_all (GOutputStream  *stream,
 254                            const void     *buffer,
 255                            gsize           count,
 256                            gsize          *bytes_written,
 257                            GCancellable   *cancellable,
 258                            GError        **error)
 259 {
 260   gsize _bytes_written;
 261   gssize res;
 262
 263   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 264   g_return_val_if_fail (buffer != NULL, FALSE);
 265
 266   _bytes_written = 0;
 267   while (_bytes_written < count)
 268     {
 269       res = g_output_stream_write (stream, (char *)buffer + _bytes_written, count - _bytes_written,
 270                                    cancellable, error);
 271       if (res == -1)
 272         {
 273           if (bytes_written)
 274             *bytes_written = _bytes_written;
 275           return FALSE;
 276         }
 277
 278       if (res == 0)
 279         g_warning ("Write returned zero without error");
 280
 281       _bytes_written += res;
 282     }
 283
 284   if (bytes_written)
 285     *bytes_written = _bytes_written;
 286
 287   return TRUE;
 288 }
 289
 290 /**
 291  * g_output_stream_flush:
 292  * @stream: a #GOutputStream.
 293  * @cancellable: optional cancellable object
 294  * @error: location to store the error occuring, or %NULL to ignore
 295  *
 296  * Flushed any outstanding buffers in the stream. Will block during
 297  * the operation. Closing the stream will implicitly cause a flush.
 298  *
 299  * This function is optional for inherited classes.
 300  *
 301  * If @cancellable is not %NULL, then the operation can be cancelled by
 302  * triggering the cancellable object from another thread. If the operation
 303  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 304  *
 305  * Return value: %TRUE on success, %FALSE on error
 306  **/
 307 gboolean
 308 g_output_stream_flush (GOutputStream  *stream,
 309                        GCancellable   *cancellable,
 310                        GError        **error)
 311 {
 312   GOutputStreamClass *class;
 313   gboolean res;
 314
 315   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 316
 317   if (!g_output_stream_set_pending (stream, error))
 318     return FALSE;
 319
 320   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 321
 322   res = TRUE;
 323   if (class->flush)
 324     {
 325       if (cancellable)
 326         g_cancellable_push_current (cancellable);
 327
 328       res = class->flush (stream, cancellable, error);
 329
 330       if (cancellable)
 331         g_cancellable_pop_current (cancellable);
 332     }
 333
 334   g_output_stream_clear_pending (stream);
 335
 336   return res;
 337 }
 338
 339 /**
 340  * g_output_stream_splice:
 341  * @stream: a #GOutputStream.
 342  * @source: a #GInputStream.
 343  * @flags: a set of #GOutputStreamSpliceFlags.
 344  * @cancellable: optional #GCancellable object, %NULL to ignore.
 345  * @error: a #GError location to store the error occuring, or %NULL to
 346  * ignore.
 347  *
 348  * Splices an input stream into an output stream.
 349  *
 350  * Returns: a #gssize containing the size of the data spliced, or
 351  *     -1 if an error occurred.
 352  **/
 353 gssize
 354 g_output_stream_splice (GOutputStream             *stream,
 355                         GInputStream              *source,
 356                         GOutputStreamSpliceFlags   flags,
 357                         GCancellable              *cancellable,
 358                         GError                   **error)
 359 {
 360   GOutputStreamClass *class;
 361   gssize bytes_copied;
 362
 363   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 364   g_return_val_if_fail (G_IS_INPUT_STREAM (source), -1);
 365
 366   if (g_input_stream_is_closed (source))
 367     {
 368       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
 369                            _("Source stream is already closed"));
 370       return -1;
 371     }
 372
 373   if (!g_output_stream_set_pending (stream, error))
 374     return -1;
 375
 376   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 377
 378   if (cancellable)
 379     g_cancellable_push_current (cancellable);
 380
 381   bytes_copied = class->splice (stream, source, flags, cancellable, error);
 382
 383   if (cancellable)
 384     g_cancellable_pop_current (cancellable);
 385
 386   g_output_stream_clear_pending (stream);
 387
 388   return bytes_copied;
 389 }
 390
 391 static gssize
 392 g_output_stream_real_splice (GOutputStream             *stream,
 393                              GInputStream              *source,
 394                              GOutputStreamSpliceFlags   flags,
 395                              GCancellable              *cancellable,
 396                              GError                   **error)
 397 {
 398   GOutputStreamClass *class = G_OUTPUT_STREAM_GET_CLASS (stream);
 399   gssize n_read, n_written;
 400   gssize bytes_copied;
 401   char buffer[8192], *p;
 402   gboolean res;
 403
 404   bytes_copied = 0;
 405   if (class->write_fn == NULL)
 406     {
 407       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 408                            _("Output stream doesn't implement write"));
 409       res = FALSE;
 410       goto notsupported;
 411     }
 412
 413   res = TRUE;
 414   do
 415     {
 416       n_read = g_input_stream_read (source, buffer, sizeof (buffer), cancellable, error);
 417       if (n_read == -1)
 418         {
 419           res = FALSE;
 420           break;
 421         }
 422
 423       if (n_read == 0)
 424         break;
 425
 426       p = buffer;
 427       while (n_read > 0)
 428         {
 429           n_written = class->write_fn (stream, p, n_read, cancellable, error);
 430           if (n_written == -1)
 431             {
 432               res = FALSE;
 433               break;
 434             }
 435
 436           p += n_written;
 437           n_read -= n_written;
 438           bytes_copied += n_written;
 439         }
 440     }
 441   while (res);
 442
 443  notsupported:
 444   if (!res)
 445     error = NULL; /* Ignore further errors */
 446
 447   if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_SOURCE)
 448     {
 449       /* Don't care about errors in source here */
 450       g_input_stream_close (source, cancellable, NULL);
 451     }
 452
 453   if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET)
 454     {
 455       /* But write errors on close are bad! */
 456       if (class->close_fn &&
 457           !class->close_fn (stream, cancellable, error))
 458         res = FALSE;
 459     }
 460
 461   if (res)
 462     return bytes_copied;
 463
 464   return -1;
 465 }
 466
 467
 468 /**
 469  * g_output_stream_close:
 470  * @stream: A #GOutputStream.
 471  * @cancellable: optional cancellable object
 472  * @error: location to store the error occuring, or %NULL to ignore
 473  *
 474  * Closes the stream, releasing resources related to it.
 475  *
 476  * Once the stream is closed, all other operations will return %G_IO_ERROR_CLOSED.
 477  * Closing a stream multiple times will not return an error.
 478  *
 479  * Closing a stream will automatically flush any outstanding buffers in the
 480  * stream.
 481  *
 482  * Streams will be automatically closed when the last reference
 483  * is dropped, but you might want to call this function to make sure
 484  * resources are released as early as possible.
 485  *
 486  * Some streams might keep the backing store of the stream (e.g. a file descriptor)
 487  * open after the stream is closed. See the documentation for the individual
 488  * stream for details.
 489  *
 490  * On failure the first error that happened will be reported, but the close
 491  * operation will finish as much as possible. A stream that failed to
 492  * close will still return %G_IO_ERROR_CLOSED for all operations. Still, it
 493  * is important to check and report the error to the user, otherwise
 494  * there might be a loss of data as all data might not be written.
 495  *
 496  * If @cancellable is not NULL, then the operation can be cancelled by
 497  * triggering the cancellable object from another thread. If the operation
 498  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 499  * Cancelling a close will still leave the stream closed, but there some streams
 500  * can use a faster close that doesn't block to e.g. check errors. On
 501  * cancellation (as with any error) there is no guarantee that all written
 502  * data will reach the target.
 503  *
 504  * Return value: %TRUE on success, %FALSE on failure
 505  **/
 506 gboolean
 507 g_output_stream_close (GOutputStream  *stream,
 508                        GCancellable   *cancellable,
 509                        GError        **error)
 510 {
 511   GOutputStreamClass *class;
 512   gboolean res;
 513
 514   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 515
 516   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 517
 518   if (stream->priv->closed)
 519     return TRUE;
 520
 521   if (!g_output_stream_set_pending (stream, error))
 522     return FALSE;
 523
 524   stream->priv->closing = TRUE;
 525
 526   if (cancellable)
 527     g_cancellable_push_current (cancellable);
 528
 529   if (class->flush)
 530     res = class->flush (stream, cancellable, error);
 531   else
 532     res = TRUE;
 533
 534   if (!res)
 535     {
 536       /* flushing caused the error that we want to return,
 537        * but we still want to close the underlying stream if possible
 538        */
 539       if (class->close_fn)
 540         class->close_fn (stream, cancellable, NULL);
 541     }
 542   else
 543     {
 544       res = TRUE;
 545       if (class->close_fn)
 546         res = class->close_fn (stream, cancellable, error);
 547     }
 548
 549   if (cancellable)
 550     g_cancellable_pop_current (cancellable);
 551
 552   stream->priv->closing = FALSE;
 553   stream->priv->closed = TRUE;
 554   g_output_stream_clear_pending (stream);
 555
 556   return res;
 557 }
 558
 559 static void
 560 async_ready_callback_wrapper (GObject      *source_object,
 561                               GAsyncResult *res,
 562                               gpointer      user_data)
 563 {
 564   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 565
 566   g_output_stream_clear_pending (stream);
 567   if (stream->priv->outstanding_callback)
 568     (*stream->priv->outstanding_callback) (source_object, res, user_data);
 569   g_object_unref (stream);
 570 }
 571
 572 typedef struct {
 573   gint io_priority;
 574   GCancellable *cancellable;
 575   GError *flush_error;
 576   gpointer user_data;
 577 } CloseUserData;
 578
 579 static void
 580 async_ready_close_callback_wrapper (GObject      *source_object,
 581                                     GAsyncResult *res,
 582                                     gpointer      user_data)
 583 {
 584   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 585   CloseUserData *data = user_data;
 586
 587   stream->priv->closing = FALSE;
 588   stream->priv->closed = TRUE;
 589
 590   g_output_stream_clear_pending (stream);
 591
 592   if (stream->priv->outstanding_callback)
 593     {
 594       if (data->flush_error != NULL)
 595         {
 596           GSimpleAsyncResult *err;
 597
 598           err = g_simple_async_result_new_from_error (source_object,
 599                                                       stream->priv->outstanding_callback,
 600                                                       data->user_data,
 601                                                       data->flush_error);
 602
 603           (*stream->priv->outstanding_callback) (source_object,
 604                                                  G_ASYNC_RESULT (err),
 605                                                  data->user_data);
 606           g_object_unref (err);
 607         }
 608       else
 609         {
 610           (*stream->priv->outstanding_callback) (source_object,
 611                                                  res,
 612                                                  data->user_data);
 613         }
 614     }
 615
 616   g_object_unref (stream);
 617
 618   if (data->cancellable)
 619     g_object_unref (data->cancellable);
 620
 621   if (data->flush_error)
 622     g_error_free (data->flush_error);
 623
 624   g_slice_free (CloseUserData, data);
 625 }
 626
 627 static void
 628 async_ready_close_flushed_callback_wrapper (GObject      *source_object,
 629                                             GAsyncResult *res,
 630                                             gpointer      user_data)
 631 {
 632   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 633   GOutputStreamClass *class;
 634   CloseUserData *data = user_data;
 635   GSimpleAsyncResult *simple;
 636
 637   /* propagate the possible error */
 638   if (G_IS_SIMPLE_ASYNC_RESULT (res))
 639     {
 640       simple = G_SIMPLE_ASYNC_RESULT (res);
 641       g_simple_async_result_propagate_error (simple, &data->flush_error);
 642     }
 643
 644   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 645
 646   /* we still close, even if there was a flush error */
 647   class->close_async (stream, data->io_priority, data->cancellable,
 648                       async_ready_close_callback_wrapper, user_data);
 649 }
 650
 651 /**
 652  * g_output_stream_write_async:
 653  * @stream: A #GOutputStream.
 654  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 655  * @count: the number of bytes to write
 656  * @io_priority: the io priority of the request.
 657  * @cancellable: optional #GCancellable object, %NULL to ignore.
 658  * @callback: callback to call when the request is satisfied
 659  * @user_data: the data to pass to callback function
 660  *
 661  * Request an asynchronous write of @count bytes from @buffer into
 662  * the stream. When the operation is finished @callback will be called.
 663  * You can then call g_output_stream_write_finish() to get the result of the
 664  * operation.
 665  *
 666  * During an async request no other sync and async calls are allowed,
 667  * and will result in %G_IO_ERROR_PENDING errors.
 668  *
 669  * A value of @count larger than %G_MAXSSIZE will cause a
 670  * %G_IO_ERROR_INVALID_ARGUMENT error.
 671  *
 672  * On success, the number of bytes written will be passed to the
 673  * @callback. It is not an error if this is not the same as the
 674  * requested size, as it can happen e.g. on a partial I/O error,
 675  * but generally we try to write as many bytes as requested.
 676  *
 677  * You are guaranteed that this method will never fail with
 678  * %G_IO_ERROR_WOULD_BLOCK - if @stream can't accept more data, the
 679  * method will just wait until this changes.
 680  *
 681  * Any outstanding I/O request with higher priority (lower numerical
 682  * value) will be executed before an outstanding request with lower
 683  * priority. Default priority is %G_PRIORITY_DEFAULT.
 684  *
 685  * The asyncronous methods have a default fallback that uses threads
 686  * to implement asynchronicity, so they are optional for inheriting
 687  * classes. However, if you override one you must override all.
 688  *
 689  * For the synchronous, blocking version of this function, see
 690  * g_output_stream_write().
 691  **/
 692 void
 693 g_output_stream_write_async (GOutputStream       *stream,
 694                              const void          *buffer,
 695                              gsize                count,
 696                              int                  io_priority,
 697                              GCancellable        *cancellable,
 698                              GAsyncReadyCallback  callback,
 699                              gpointer             user_data)
 700 {
 701   GOutputStreamClass *class;
 702   GSimpleAsyncResult *simple;
 703   GError *error = NULL;
 704
 705   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 706   g_return_if_fail (buffer != NULL);
 707
 708   if (count == 0)
 709     {
 710       simple = g_simple_async_result_new (G_OBJECT (stream),
 711                                           callback,
 712                                           user_data,
 713                                           g_output_stream_write_async);
 714       g_simple_async_result_complete_in_idle (simple);
 715       g_object_unref (simple);
 716       return;
 717     }
 718
 719   if (((gssize) count) < 0)
 720     {
 721       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 722                                            callback,
 723                                            user_data,
 724                                            G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 725                                            _("Too large count value passed to %s"),
 726                                            G_STRFUNC);
 727       return;
 728     }
 729
 730   if (!g_output_stream_set_pending (stream, &error))
 731     {
 732       g_simple_async_report_gerror_in_idle (G_OBJECT (stream),
 733                                             callback,
 734                                             user_data,
 735                                             error);
 736       g_error_free (error);
 737       return;
 738     }
 739
 740   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 741
 742   stream->priv->outstanding_callback = callback;
 743   g_object_ref (stream);
 744   class->write_async (stream, buffer, count, io_priority, cancellable,
 745                       async_ready_callback_wrapper, user_data);
 746 }
 747
 748 /**
 749  * g_output_stream_write_finish:
 750  * @stream: a #GOutputStream.
 751  * @result: a #GAsyncResult.
 752  * @error: a #GError location to store the error occuring, or %NULL to
 753  * ignore.
 754  *
 755  * Finishes a stream write operation.
 756  *
 757  * Returns: a #gssize containing the number of bytes written to the stream.
 758  **/
 759 gssize
 760 g_output_stream_write_finish (GOutputStream  *stream,
 761                               GAsyncResult   *result,
 762                               GError        **error)
 763 {
 764   GSimpleAsyncResult *simple;
 765   GOutputStreamClass *class;
 766
 767   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 768   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
 769
 770   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 771     {
 772       simple = G_SIMPLE_ASYNC_RESULT (result);
 773       if (g_simple_async_result_propagate_error (simple, error))
 774         return -1;
 775
 776       /* Special case writes of 0 bytes */
 777       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_write_async)
 778         return 0;
 779     }
 780
 781   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 782   return class->write_finish (stream, result, error);
 783 }
 784
 785 typedef struct {
 786   GInputStream *source;
 787   gpointer user_data;
 788   GAsyncReadyCallback callback;
 789 } SpliceUserData;
 790
 791 static void
 792 async_ready_splice_callback_wrapper (GObject      *source_object,
 793                                      GAsyncResult *res,
 794                                      gpointer     _data)
 795 {
 796   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 797   SpliceUserData *data = _data;
 798
 799   g_output_stream_clear_pending (stream);
 800
 801   if (data->callback)
 802     (*data->callback) (source_object, res, data->user_data);
 803
 804   g_object_unref (stream);
 805   g_object_unref (data->source);
 806   g_free (data);
 807 }
 808
 809 /**
 810  * g_output_stream_splice_async:
 811  * @stream: a #GOutputStream.
 812  * @source: a #GInputStream.
 813  * @flags: a set of #GOutputStreamSpliceFlags.
 814  * @io_priority: the io priority of the request.
 815  * @cancellable: optional #GCancellable object, %NULL to ignore.
 816  * @callback: a #GAsyncReadyCallback.
 817  * @user_data: user data passed to @callback.
 818  *
 819  * Splices a stream asynchronously.
 820  * When the operation is finished @callback will be called.
 821  * You can then call g_output_stream_splice_finish() to get the
 822  * result of the operation.
 823  *
 824  * For the synchronous, blocking version of this function, see
 825  * g_output_stream_splice().
 826  **/
 827 void
 828 g_output_stream_splice_async (GOutputStream            *stream,
 829                               GInputStream             *source,
 830                               GOutputStreamSpliceFlags  flags,
 831                               int                       io_priority,
 832                               GCancellable             *cancellable,
 833                               GAsyncReadyCallback       callback,
 834                               gpointer                  user_data)
 835 {
 836   GOutputStreamClass *class;
 837   SpliceUserData *data;
 838   GError *error = NULL;
 839
 840   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 841   g_return_if_fail (G_IS_INPUT_STREAM (source));
 842
 843   if (g_input_stream_is_closed (source))
 844     {
 845       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 846                                            callback,
 847                                            user_data,
 848                                            G_IO_ERROR, G_IO_ERROR_CLOSED,
 849                                            _("Source stream is already closed"));
 850       return;
 851     }
 852
 853   if (!g_output_stream_set_pending (stream, &error))
 854     {
 855       g_simple_async_report_gerror_in_idle (G_OBJECT (stream),
 856                                             callback,
 857                                             user_data,
 858                                             error);
 859       g_error_free (error);
 860       return;
 861     }
 862
 863   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 864
 865   data = g_new0 (SpliceUserData, 1);
 866   data->callback = callback;
 867   data->user_data = user_data;
 868   data->source = g_object_ref (source);
 869
 870   g_object_ref (stream);
 871   class->splice_async (stream, source, flags, io_priority, cancellable,
 872                       async_ready_splice_callback_wrapper, data);
 873 }
 874
 875 /**
 876  * g_output_stream_splice_finish:
 877  * @stream: a #GOutputStream.
 878  * @result: a #GAsyncResult.
 879  * @error: a #GError location to store the error occuring, or %NULL to
 880  * ignore.
 881  *
 882  * Finishes an asynchronous stream splice operation.
 883  *
 884  * Returns: a #gssize of the number of bytes spliced.
 885  **/
 886 gssize
 887 g_output_stream_splice_finish (GOutputStream  *stream,
 888                                GAsyncResult   *result,
 889                                GError        **error)
 890 {
 891   GSimpleAsyncResult *simple;
 892   GOutputStreamClass *class;
 893
 894   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 895   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
 896
 897   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 898     {
 899       simple = G_SIMPLE_ASYNC_RESULT (result);
 900       if (g_simple_async_result_propagate_error (simple, error))
 901         return -1;
 902     }
 903
 904   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 905   return class->splice_finish (stream, result, error);
 906 }
 907
 908 /**
 909  * g_output_stream_flush_async:
 910  * @stream: a #GOutputStream.
 911  * @io_priority: the io priority of the request.
 912  * @cancellable: optional #GCancellable object, %NULL to ignore.
 913  * @callback: a #GAsyncReadyCallback to call when the request is satisfied
 914  * @user_data: the data to pass to callback function
 915  *
 916  * Flushes a stream asynchronously.
 917  * For behaviour details see g_output_stream_flush().
 918  *
 919  * When the operation is finished @callback will be
 920  * called. You can then call g_output_stream_flush_finish() to get the
 921  * result of the operation.
 922  **/
 923 void
 924 g_output_stream_flush_async (GOutputStream       *stream,
 925                              int                  io_priority,
 926                              GCancellable        *cancellable,
 927                              GAsyncReadyCallback  callback,
 928                              gpointer             user_data)
 929 {
 930   GOutputStreamClass *class;
 931   GSimpleAsyncResult *simple;
 932   GError *error = NULL;
 933
 934   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 935
 936   if (!g_output_stream_set_pending (stream, &error))
 937     {
 938       g_simple_async_report_gerror_in_idle (G_OBJECT (stream),
 939                                             callback,
 940                                             user_data,
 941                                             error);
 942       g_error_free (error);
 943       return;
 944     }
 945
 946   stream->priv->outstanding_callback = callback;
 947   g_object_ref (stream);
 948
 949   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 950
 951   if (class->flush_async == NULL)
 952     {
 953       simple = g_simple_async_result_new (G_OBJECT (stream),
 954                                           async_ready_callback_wrapper,
 955                                           user_data,
 956                                           g_output_stream_flush_async);
 957       g_simple_async_result_complete_in_idle (simple);
 958       g_object_unref (simple);
 959       return;
 960     }
 961
 962   class->flush_async (stream, io_priority, cancellable,
 963                       async_ready_callback_wrapper, user_data);
 964 }
 965
 966 /**
 967  * g_output_stream_flush_finish:
 968  * @stream: a #GOutputStream.
 969  * @result: a GAsyncResult.
 970  * @error: a #GError location to store the error occuring, or %NULL to
 971  * ignore.
 972  *
 973  * Finishes flushing an output stream.
 974  *
 975  * Returns: %TRUE if flush operation suceeded, %FALSE otherwise.
 976  **/
 977 gboolean
 978 g_output_stream_flush_finish (GOutputStream  *stream,
 979                               GAsyncResult   *result,
 980                               GError        **error)
 981 {
 982   GSimpleAsyncResult *simple;
 983   GOutputStreamClass *klass;
 984
 985   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 986   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
 987
 988   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 989     {
 990       simple = G_SIMPLE_ASYNC_RESULT (result);
 991       if (g_simple_async_result_propagate_error (simple, error))
 992         return FALSE;
 993
 994       /* Special case default implementation */
 995       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_flush_async)
 996         return TRUE;
 997     }
 998
 999   klass = G_OUTPUT_STREAM_GET_CLASS (stream);
1000   return klass->flush_finish (stream, result, error);
1001 }
1002
1003
1004 /**
1005  * g_output_stream_close_async:
1006  * @stream: A #GOutputStream.
1007  * @io_priority: the io priority of the request.
1008  * @callback: callback to call when the request is satisfied
1009  * @user_data: the data to pass to callback function
1010  * @cancellable: optional cancellable object
1011  *
1012  * Requests an asynchronous close of the stream, releasing resources
1013  * related to it. When the operation is finished @callback will be
1014  * called. You can then call g_output_stream_close_finish() to get
1015  * the result of the operation.
1016  *
1017  * For behaviour details see g_output_stream_close().
1018  *
1019  * The asyncronous methods have a default fallback that uses threads
1020  * to implement asynchronicity, so they are optional for inheriting
1021  * classes. However, if you override one you must override all.
1022  **/
1023 void
1024 g_output_stream_close_async (GOutputStream       *stream,
1025                              int                  io_priority,
1026                              GCancellable        *cancellable,
1027                              GAsyncReadyCallback  callback,
1028                              gpointer             user_data)
1029 {
1030   GOutputStreamClass *class;
1031   GSimpleAsyncResult *simple;
1032   GError *error = NULL;
1033   CloseUserData *data;
1034
1035   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1036
1037   if (stream->priv->closed)
1038     {
1039       simple = g_simple_async_result_new (G_OBJECT (stream),
1040                                           callback,
1041                                           user_data,
1042                                           g_output_stream_close_async);
1043       g_simple_async_result_complete_in_idle (simple);
1044       g_object_unref (simple);
1045       return;
1046     }
1047
1048   if (!g_output_stream_set_pending (stream, &error))
1049     {
1050       g_simple_async_report_gerror_in_idle (G_OBJECT (stream),
1051                                             callback,
1052                                             user_data,
1053                                             error);
1054       g_error_free (error);
1055       return;
1056     }
1057
1058   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1059   stream->priv->closing = TRUE;
1060   stream->priv->outstanding_callback = callback;
1061   g_object_ref (stream);
1062
1063   data = g_slice_new0 (CloseUserData);
1064
1065   if (cancellable != NULL)
1066     data->cancellable = g_object_ref (cancellable);
1067
1068   data->io_priority = io_priority;
1069   data->user_data = user_data;
1070
1071   /* Call close_async directly if there is no need to flush, or if the flush
1072      can be done sync (in the output stream async close thread) */
1073   if (class->flush_async == NULL ||
1074       (class->flush_async == g_output_stream_real_flush_async &&
1075        (class->flush == NULL || class->close_async == g_output_stream_real_close_async)))
1076     {
1077       class->close_async (stream, io_priority, cancellable,
1078                           async_ready_close_callback_wrapper, data);
1079     }
1080   else
1081     {
1082       /* First do an async flush, then do the async close in the callback
1083          wrapper (see async_ready_close_flushed_callback_wrapper) */
1084       class->flush_async (stream, io_priority, cancellable,
1085                           async_ready_close_flushed_callback_wrapper, data);
1086     }
1087 }
1088
1089 /**
1090  * g_output_stream_close_finish:
1091  * @stream: a #GOutputStream.
1092  * @result: a #GAsyncResult.
1093  * @error: a #GError location to store the error occuring, or %NULL to
1094  * ignore.
1095  *
1096  * Closes an output stream.
1097  *
1098  * Returns: %TRUE if stream was successfully closed, %FALSE otherwise.
1099  **/
1100 gboolean
1101 g_output_stream_close_finish (GOutputStream  *stream,
1102                               GAsyncResult   *result,
1103                               GError        **error)
1104 {
1105   GSimpleAsyncResult *simple;
1106   GOutputStreamClass *class;
1107
1108   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1109   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
1110
1111   if (G_IS_SIMPLE_ASYNC_RESULT (result))
1112     {
1113       simple = G_SIMPLE_ASYNC_RESULT (result);
1114       if (g_simple_async_result_propagate_error (simple, error))
1115         return FALSE;
1116
1117       /* Special case already closed */
1118       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_close_async)
1119         return TRUE;
1120     }
1121
1122   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1123   return class->close_finish (stream, result, error);
1124 }
1125
1126 /**
1127  * g_output_stream_is_closed:
1128  * @stream: a #GOutputStream.
1129  *
1130  * Checks if an output stream has already been closed.
1131  *
1132  * Returns: %TRUE if @stream is closed. %FALSE otherwise.
1133  **/
1134 gboolean
1135 g_output_stream_is_closed (GOutputStream *stream)
1136 {
1137   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
1138
1139   return stream->priv->closed;
1140 }
1141
1142 /**
1143  * g_output_stream_is_closing:
1144  * @stream: a #GOutputStream.
1145  *
1146  * Checks if an output stream is being closed. This can be
1147  * used inside e.g. a flush implementation to see if the
1148  * flush (or other i/o operation) is called from within
1149  * the closing operation.
1150  *
1151  * Returns: %TRUE if @stream is being closed. %FALSE otherwise.
1152  *
1153  * Since: 2.24
1154  **/
1155 gboolean
1156 g_output_stream_is_closing (GOutputStream *stream)
1157 {
1158   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
1159
1160   return stream->priv->closing;
1161 }
1162
1163 /**
1164  * g_output_stream_has_pending:
1165  * @stream: a #GOutputStream.
1166  *
1167  * Checks if an ouput stream has pending actions.
1168  *
1169  * Returns: %TRUE if @stream has pending actions.
1170  **/
1171 gboolean
1172 g_output_stream_has_pending (GOutputStream *stream)
1173 {
1174   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1175
1176   return stream->priv->pending;
1177 }
1178
1179 /**
1180  * g_output_stream_set_pending:
1181  * @stream: a #GOutputStream.
1182  * @error: a #GError location to store the error occuring, or %NULL to
1183  * ignore.
1184  *
1185  * Sets @stream to have actions pending. If the pending flag is
1186  * already set or @stream is closed, it will return %FALSE and set
1187  * @error.
1188  *
1189  * Return value: %TRUE if pending was previously unset and is now set.
1190  **/
1191 gboolean
1192 g_output_stream_set_pending (GOutputStream *stream,
1193                              GError **error)
1194 {
1195   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1196
1197   if (stream->priv->closed)
1198     {
1199       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
1200                            _("Stream is already closed"));
1201       return FALSE;
1202     }
1203
1204   if (stream->priv->pending)
1205     {
1206       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PENDING,
1207                            /* Translators: This is an error you get if there is
1208                             * already an operation running against this stream when
1209                             * you try to start one */
1210                            _("Stream has outstanding operation"));
1211       return FALSE;
1212     }
1213
1214   stream->priv->pending = TRUE;
1215   return TRUE;
1216 }
1217
1218 /**
1219  * g_output_stream_clear_pending:
1220  * @stream: output stream
1221  *
1222  * Clears the pending flag on @stream.
1223  **/
1224 void
1225 g_output_stream_clear_pending (GOutputStream *stream)
1226 {
1227   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1228
1229   stream->priv->pending = FALSE;
1230 }
1231
1232
1233 /********************************************
1234  *   Default implementation of async ops    *
1235  ********************************************/
1236
1237 typedef struct {
1238   const void         *buffer;
1239   gsize               count_requested;
1240   gssize              count_written;
1241 } WriteData;
1242
1243 static void
1244 write_async_thread (GSimpleAsyncResult *res,
1245                     GObject            *object,
1246                     GCancellable       *cancellable)
1247 {
1248   WriteData *op;
1249   GOutputStreamClass *class;
1250   GError *error = NULL;
1251
1252   class = G_OUTPUT_STREAM_GET_CLASS (object);
1253   op = g_simple_async_result_get_op_res_gpointer (res);
1254   op->count_written = class->write_fn (G_OUTPUT_STREAM (object), op->buffer, op->count_requested,
1255                                        cancellable, &error);
1256   if (op->count_written == -1)
1257     {
1258       g_simple_async_result_set_from_error (res, error);
1259       g_error_free (error);
1260     }
1261 }
1262
1263 static void
1264 g_output_stream_real_write_async (GOutputStream       *stream,
1265                                   const void          *buffer,
1266                                   gsize                count,
1267                                   int                  io_priority,
1268                                   GCancellable        *cancellable,
1269                                   GAsyncReadyCallback  callback,
1270                                   gpointer             user_data)
1271 {
1272   GSimpleAsyncResult *res;
1273   WriteData *op;
1274
1275   op = g_new0 (WriteData, 1);
1276   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1277   g_simple_async_result_set_op_res_gpointer (res, op, g_free);
1278   op->buffer = buffer;
1279   op->count_requested = count;
1280
1281   g_simple_async_result_run_in_thread (res, write_async_thread, io_priority, cancellable);
1282   g_object_unref (res);
1283 }
1284
1285 static gssize
1286 g_output_stream_real_write_finish (GOutputStream  *stream,
1287                                    GAsyncResult   *result,
1288                                    GError        **error)
1289 {
1290   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1291   WriteData *op;
1292
1293   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_write_async);
1294   op = g_simple_async_result_get_op_res_gpointer (simple);
1295   return op->count_written;
1296 }
1297
1298 typedef struct {
1299   GInputStream *source;
1300   GOutputStreamSpliceFlags flags;
1301   gssize bytes_copied;
1302 } SpliceData;
1303
1304 static void
1305 splice_async_thread (GSimpleAsyncResult *result,
1306                      GObject            *object,
1307                      GCancellable       *cancellable)
1308 {
1309   SpliceData *op;
1310   GOutputStreamClass *class;
1311   GError *error = NULL;
1312   GOutputStream *stream;
1313
1314   stream = G_OUTPUT_STREAM (object);
1315   class = G_OUTPUT_STREAM_GET_CLASS (object);
1316   op = g_simple_async_result_get_op_res_gpointer (result);
1317
1318   op->bytes_copied = class->splice (stream,
1319                                     op->source,
1320                                     op->flags,
1321                                     cancellable,
1322                                     &error);
1323   if (op->bytes_copied == -1)
1324     {
1325       g_simple_async_result_set_from_error (result, error);
1326       g_error_free (error);
1327     }
1328 }
1329
1330 static void
1331 g_output_stream_real_splice_async (GOutputStream             *stream,
1332                                    GInputStream              *source,
1333                                    GOutputStreamSpliceFlags   flags,
1334                                    int                        io_priority,
1335                                    GCancellable              *cancellable,
1336                                    GAsyncReadyCallback        callback,
1337                                    gpointer                   user_data)
1338 {
1339   GSimpleAsyncResult *res;
1340   SpliceData *op;
1341
1342   op = g_new0 (SpliceData, 1);
1343   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_splice_async);
1344   g_simple_async_result_set_op_res_gpointer (res, op, g_free);
1345   op->flags = flags;
1346   op->source = source;
1347
1348   /* TODO: In the case where both source and destintion have
1349      non-threadbased async calls we can use a true async copy here */
1350
1351   g_simple_async_result_run_in_thread (res, splice_async_thread, io_priority, cancellable);
1352   g_object_unref (res);
1353 }
1354
1355 static gssize
1356 g_output_stream_real_splice_finish (GOutputStream  *stream,
1357                                     GAsyncResult   *result,
1358                                     GError        **error)
1359 {
1360   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1361   SpliceData *op;
1362
1363   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_splice_async);
1364   op = g_simple_async_result_get_op_res_gpointer (simple);
1365   return op->bytes_copied;
1366 }
1367
1368
1369 static void
1370 flush_async_thread (GSimpleAsyncResult *res,
1371                     GObject            *object,
1372                     GCancellable       *cancellable)
1373 {
1374   GOutputStreamClass *class;
1375   gboolean result;
1376   GError *error = NULL;
1377
1378   class = G_OUTPUT_STREAM_GET_CLASS (object);
1379   result = TRUE;
1380   if (class->flush)
1381     result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error);
1382
1383   if (!result)
1384     {
1385       g_simple_async_result_set_from_error (res, error);
1386       g_error_free (error);
1387     }
1388 }
1389
1390 static void
1391 g_output_stream_real_flush_async (GOutputStream       *stream,
1392                                   int                  io_priority,
1393                                   GCancellable        *cancellable,
1394                                   GAsyncReadyCallback  callback,
1395                                   gpointer             user_data)
1396 {
1397   GSimpleAsyncResult *res;
1398
1399   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1400
1401   g_simple_async_result_run_in_thread (res, flush_async_thread, io_priority, cancellable);
1402   g_object_unref (res);
1403 }
1404
1405 static gboolean
1406 g_output_stream_real_flush_finish (GOutputStream  *stream,
1407                                    GAsyncResult   *result,
1408                                    GError        **error)
1409 {
1410   return TRUE;
1411 }
1412
1413 static void
1414 close_async_thread (GSimpleAsyncResult *res,
1415                     GObject            *object,
1416                     GCancellable       *cancellable)
1417 {
1418   GOutputStreamClass *class;
1419   GError *error = NULL;
1420   gboolean result = TRUE;
1421
1422   class = G_OUTPUT_STREAM_GET_CLASS (object);
1423
1424   /* Do a flush here if there is a flush function, and we did not have to do
1425      an async flush before (see g_output_stream_close_async) */
1426   if (class->flush != NULL &&
1427       (class->flush_async == NULL ||
1428        class->flush_async == g_output_stream_real_flush_async))
1429     {
1430       result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error);
1431     }
1432
1433   /* Auto handling of cancelation disabled, and ignore
1434      cancellation, since we want to close things anyway, although
1435      possibly in a quick-n-dirty way. At least we never want to leak
1436      open handles */
1437
1438   if (class->close_fn)
1439     {
1440       /* Make sure to close, even if the flush failed (see sync close) */
1441       if (!result)
1442         class->close_fn (G_OUTPUT_STREAM (object), cancellable, NULL);
1443       else
1444         result = class->close_fn (G_OUTPUT_STREAM (object), cancellable, &error);
1445
1446       if (!result)
1447         {
1448           g_simple_async_result_set_from_error (res, error);
1449           g_error_free (error);
1450         }
1451     }
1452 }
1453
1454 static void
1455 g_output_stream_real_close_async (GOutputStream       *stream,
1456                                   int                  io_priority,
1457                                   GCancellable        *cancellable,
1458                                   GAsyncReadyCallback  callback,
1459                                   gpointer             user_data)
1460 {
1461   GSimpleAsyncResult *res;
1462
1463   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_close_async);
1464
1465   g_simple_async_result_set_handle_cancellation (res, FALSE);
1466
1467   g_simple_async_result_run_in_thread (res, close_async_thread, io_priority, cancellable);
1468   g_object_unref (res);
1469 }
1470
1471 static gboolean
1472 g_output_stream_real_close_finish (GOutputStream  *stream,
1473                                    GAsyncResult   *result,
1474                                    GError        **error)
1475 {
1476   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1477   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_close_async);
1478   return TRUE;
1479 }