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 static gboolean _g_output_stream_close_internal    (GOutputStream             *stream,
  99                                                     GCancellable              *cancellable,
 100                                                     GError                   **error);
 101
 102 static void
 103 g_output_stream_finalize (GObject *object)
 104 {
 105   G_OBJECT_CLASS (g_output_stream_parent_class)->finalize (object);
 106 }
 107
 108 static void
 109 g_output_stream_dispose (GObject *object)
 110 {
 111   GOutputStream *stream;
 112
 113   stream = G_OUTPUT_STREAM (object);
 114
 115   if (!stream->priv->closed)
 116     g_output_stream_close (stream, NULL, NULL);
 117
 118   G_OBJECT_CLASS (g_output_stream_parent_class)->dispose (object);
 119 }
 120
 121 static void
 122 g_output_stream_class_init (GOutputStreamClass *klass)
 123 {
 124   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 125
 126   g_type_class_add_private (klass, sizeof (GOutputStreamPrivate));
 127
 128   gobject_class->finalize = g_output_stream_finalize;
 129   gobject_class->dispose = g_output_stream_dispose;
 130
 131   klass->splice = g_output_stream_real_splice;
 132
 133   klass->write_async = g_output_stream_real_write_async;
 134   klass->write_finish = g_output_stream_real_write_finish;
 135   klass->splice_async = g_output_stream_real_splice_async;
 136   klass->splice_finish = g_output_stream_real_splice_finish;
 137   klass->flush_async = g_output_stream_real_flush_async;
 138   klass->flush_finish = g_output_stream_real_flush_finish;
 139   klass->close_async = g_output_stream_real_close_async;
 140   klass->close_finish = g_output_stream_real_close_finish;
 141 }
 142
 143 static void
 144 g_output_stream_init (GOutputStream *stream)
 145 {
 146   stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream,
 147                                               G_TYPE_OUTPUT_STREAM,
 148                                               GOutputStreamPrivate);
 149 }
 150
 151 /**
 152  * g_output_stream_write:
 153  * @stream: a #GOutputStream.
 154  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 155  * @count: the number of bytes to write
 156  * @cancellable: (allow-none): optional cancellable object
 157  * @error: location to store the error occurring, or %NULL to ignore
 158  *
 159  * Tries to write @count bytes from @buffer into the stream. Will block
 160  * during the operation.
 161  *
 162  * If count is 0, returns 0 and does nothing. A value of @count
 163  * larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
 164  *
 165  * On success, the number of bytes written to the stream is returned.
 166  * It is not an error if this is not the same as the requested size, as it
 167  * can happen e.g. on a partial I/O error, or if there is not enough
 168  * storage in the stream. All writes block until at least one byte
 169  * is written or an error occurs; 0 is never returned (unless
 170  * @count is 0).
 171  *
 172  * If @cancellable is not NULL, then the operation can be cancelled by
 173  * triggering the cancellable object from another thread. If the operation
 174  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an
 175  * operation was partially finished when the operation was cancelled the
 176  * partial result will be returned, without an error.
 177  *
 178  * On error -1 is returned and @error is set accordingly.
 179  *
 180  * Return value: Number of bytes written, or -1 on error
 181  **/
 182 gssize
 183 g_output_stream_write (GOutputStream  *stream,
 184                        const void     *buffer,
 185                        gsize           count,
 186                        GCancellable   *cancellable,
 187                        GError        **error)
 188 {
 189   GOutputStreamClass *class;
 190   gssize res;
 191
 192   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 193   g_return_val_if_fail (buffer != NULL, 0);
 194
 195   if (count == 0)
 196     return 0;
 197
 198   if (((gssize) count) < 0)
 199     {
 200       g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 201                    _("Too large count value passed to %s"), G_STRFUNC);
 202       return -1;
 203     }
 204
 205   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 206
 207   if (class->write_fn == NULL)
 208     {
 209       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 210                            _("Output stream doesn't implement write"));
 211       return -1;
 212     }
 213
 214   if (!g_output_stream_set_pending (stream, error))
 215     return -1;
 216
 217   if (cancellable)
 218     g_cancellable_push_current (cancellable);
 219
 220   res = class->write_fn (stream, buffer, count, cancellable, error);
 221
 222   if (cancellable)
 223     g_cancellable_pop_current (cancellable);
 224
 225   g_output_stream_clear_pending (stream);
 226
 227   return res;
 228 }
 229
 230 /**
 231  * g_output_stream_write_all:
 232  * @stream: a #GOutputStream.
 233  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 234  * @count: the number of bytes to write
 235  * @bytes_written: (out): location to store the number of bytes that was
 236  *     written to the stream
 237  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 238  * @error: location to store the error occurring, or %NULL to ignore
 239  *
 240  * Tries to write @count bytes from @buffer into the stream. Will block
 241  * during the operation.
 242  *
 243  * This function is similar to g_output_stream_write(), except it tries to
 244  * write as many bytes as requested, only stopping on an error.
 245  *
 246  * On a successful write of @count bytes, %TRUE is returned, and @bytes_written
 247  * is set to @count.
 248  *
 249  * If there is an error during the operation FALSE is returned and @error
 250  * is set to indicate the error status, @bytes_written is updated to contain
 251  * the number of bytes written into the stream before the error occurred.
 252  *
 253  * Return value: %TRUE on success, %FALSE if there was an error
 254  **/
 255 gboolean
 256 g_output_stream_write_all (GOutputStream  *stream,
 257                            const void     *buffer,
 258                            gsize           count,
 259                            gsize          *bytes_written,
 260                            GCancellable   *cancellable,
 261                            GError        **error)
 262 {
 263   gsize _bytes_written;
 264   gssize res;
 265
 266   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 267   g_return_val_if_fail (buffer != NULL, FALSE);
 268
 269   _bytes_written = 0;
 270   while (_bytes_written < count)
 271     {
 272       res = g_output_stream_write (stream, (char *)buffer + _bytes_written, count - _bytes_written,
 273                                    cancellable, error);
 274       if (res == -1)
 275         {
 276           if (bytes_written)
 277             *bytes_written = _bytes_written;
 278           return FALSE;
 279         }
 280
 281       if (res == 0)
 282         g_warning ("Write returned zero without error");
 283
 284       _bytes_written += res;
 285     }
 286
 287   if (bytes_written)
 288     *bytes_written = _bytes_written;
 289
 290   return TRUE;
 291 }
 292
 293 /**
 294  * g_output_stream_flush:
 295  * @stream: a #GOutputStream.
 296  * @cancellable: (allow-none): optional cancellable object
 297  * @error: location to store the error occurring, or %NULL to ignore
 298  *
 299  * Forces a write of all user-space buffered data for the given
 300  * @stream. Will block during the operation. Closing the stream will
 301  * implicitly cause a flush.
 302  *
 303  * This function is optional for inherited classes.
 304  *
 305  * If @cancellable is not %NULL, then the operation can be cancelled by
 306  * triggering the cancellable object from another thread. If the operation
 307  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 308  *
 309  * Return value: %TRUE on success, %FALSE on error
 310  **/
 311 gboolean
 312 g_output_stream_flush (GOutputStream  *stream,
 313                        GCancellable   *cancellable,
 314                        GError        **error)
 315 {
 316   GOutputStreamClass *class;
 317   gboolean res;
 318
 319   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 320
 321   if (!g_output_stream_set_pending (stream, error))
 322     return FALSE;
 323
 324   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 325
 326   res = TRUE;
 327   if (class->flush)
 328     {
 329       if (cancellable)
 330         g_cancellable_push_current (cancellable);
 331
 332       res = class->flush (stream, cancellable, error);
 333
 334       if (cancellable)
 335         g_cancellable_pop_current (cancellable);
 336     }
 337
 338   g_output_stream_clear_pending (stream);
 339
 340   return res;
 341 }
 342
 343 /**
 344  * g_output_stream_splice:
 345  * @stream: a #GOutputStream.
 346  * @source: a #GInputStream.
 347  * @flags: a set of #GOutputStreamSpliceFlags.
 348  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 349  * @error: a #GError location to store the error occurring, or %NULL to
 350  * ignore.
 351  *
 352  * Splices an input stream into an output stream.
 353  *
 354  * Returns: a #gssize containing the size of the data spliced, or
 355  *     -1 if an error occurred. Note that if the number of bytes
 356  *     spliced is greater than %G_MAXSSIZE, then that will be
 357  *     returned, and there is no way to determine the actual number
 358  *     of bytes spliced.
 359  **/
 360 gssize
 361 g_output_stream_splice (GOutputStream             *stream,
 362                         GInputStream              *source,
 363                         GOutputStreamSpliceFlags   flags,
 364                         GCancellable              *cancellable,
 365                         GError                   **error)
 366 {
 367   GOutputStreamClass *class;
 368   gssize bytes_copied;
 369
 370   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 371   g_return_val_if_fail (G_IS_INPUT_STREAM (source), -1);
 372
 373   if (g_input_stream_is_closed (source))
 374     {
 375       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
 376                            _("Source stream is already closed"));
 377       return -1;
 378     }
 379
 380   if (!g_output_stream_set_pending (stream, error))
 381     return -1;
 382
 383   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 384
 385   if (cancellable)
 386     g_cancellable_push_current (cancellable);
 387
 388   bytes_copied = class->splice (stream, source, flags, cancellable, error);
 389
 390   if (cancellable)
 391     g_cancellable_pop_current (cancellable);
 392
 393   g_output_stream_clear_pending (stream);
 394
 395   return bytes_copied;
 396 }
 397
 398 static gssize
 399 g_output_stream_real_splice (GOutputStream             *stream,
 400                              GInputStream              *source,
 401                              GOutputStreamSpliceFlags   flags,
 402                              GCancellable              *cancellable,
 403                              GError                   **error)
 404 {
 405   GOutputStreamClass *class = G_OUTPUT_STREAM_GET_CLASS (stream);
 406   gssize n_read, n_written;
 407   gsize bytes_copied;
 408   char buffer[8192], *p;
 409   gboolean res;
 410
 411   bytes_copied = 0;
 412   if (class->write_fn == NULL)
 413     {
 414       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 415                            _("Output stream doesn't implement write"));
 416       res = FALSE;
 417       goto notsupported;
 418     }
 419
 420   res = TRUE;
 421   do
 422     {
 423       n_read = g_input_stream_read (source, buffer, sizeof (buffer), cancellable, error);
 424       if (n_read == -1)
 425         {
 426           res = FALSE;
 427           break;
 428         }
 429
 430       if (n_read == 0)
 431         break;
 432
 433       p = buffer;
 434       while (n_read > 0)
 435         {
 436           n_written = class->write_fn (stream, p, n_read, cancellable, error);
 437           if (n_written == -1)
 438             {
 439               res = FALSE;
 440               break;
 441             }
 442
 443           p += n_written;
 444           n_read -= n_written;
 445           bytes_copied += n_written;
 446         }
 447
 448       if (bytes_copied > G_MAXSSIZE)
 449         bytes_copied = G_MAXSSIZE;
 450     }
 451   while (res);
 452
 453  notsupported:
 454   if (!res)
 455     error = NULL; /* Ignore further errors */
 456
 457   if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_SOURCE)
 458     {
 459       /* Don't care about errors in source here */
 460       g_input_stream_close (source, cancellable, NULL);
 461     }
 462
 463   if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET)
 464     {
 465       /* But write errors on close are bad! */
 466       res = _g_output_stream_close_internal (stream, cancellable, error);
 467     }
 468
 469   if (res)
 470     return bytes_copied;
 471
 472   return -1;
 473 }
 474
 475 /* Must always be called inside
 476  * g_output_stream_set_pending()/g_output_stream_clear_pending(). */
 477 static gboolean
 478 _g_output_stream_close_internal (GOutputStream  *stream,
 479                                  GCancellable   *cancellable,
 480                                  GError        **error)
 481 {
 482   GOutputStreamClass *class;
 483   gboolean res;
 484
 485   if (stream->priv->closed)
 486     return TRUE;
 487
 488   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 489
 490   stream->priv->closing = TRUE;
 491
 492   if (cancellable)
 493     g_cancellable_push_current (cancellable);
 494
 495   if (class->flush)
 496     res = class->flush (stream, cancellable, error);
 497   else
 498     res = TRUE;
 499
 500   if (!res)
 501     {
 502       /* flushing caused the error that we want to return,
 503        * but we still want to close the underlying stream if possible
 504        */
 505       if (class->close_fn)
 506         class->close_fn (stream, cancellable, NULL);
 507     }
 508   else
 509     {
 510       res = TRUE;
 511       if (class->close_fn)
 512         res = class->close_fn (stream, cancellable, error);
 513     }
 514
 515   if (cancellable)
 516     g_cancellable_pop_current (cancellable);
 517
 518   stream->priv->closing = FALSE;
 519   stream->priv->closed = TRUE;
 520
 521   return res;
 522 }
 523
 524 /**
 525  * g_output_stream_close:
 526  * @stream: A #GOutputStream.
 527  * @cancellable: (allow-none): optional cancellable object
 528  * @error: location to store the error occurring, or %NULL to ignore
 529  *
 530  * Closes the stream, releasing resources related to it.
 531  *
 532  * Once the stream is closed, all other operations will return %G_IO_ERROR_CLOSED.
 533  * Closing a stream multiple times will not return an error.
 534  *
 535  * Closing a stream will automatically flush any outstanding buffers in the
 536  * stream.
 537  *
 538  * Streams will be automatically closed when the last reference
 539  * is dropped, but you might want to call this function to make sure
 540  * resources are released as early as possible.
 541  *
 542  * Some streams might keep the backing store of the stream (e.g. a file descriptor)
 543  * open after the stream is closed. See the documentation for the individual
 544  * stream for details.
 545  *
 546  * On failure the first error that happened will be reported, but the close
 547  * operation will finish as much as possible. A stream that failed to
 548  * close will still return %G_IO_ERROR_CLOSED for all operations. Still, it
 549  * is important to check and report the error to the user, otherwise
 550  * there might be a loss of data as all data might not be written.
 551  *
 552  * If @cancellable is not NULL, then the operation can be cancelled by
 553  * triggering the cancellable object from another thread. If the operation
 554  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 555  * Cancelling a close will still leave the stream closed, but there some streams
 556  * can use a faster close that doesn't block to e.g. check errors. On
 557  * cancellation (as with any error) there is no guarantee that all written
 558  * data will reach the target.
 559  *
 560  * Return value: %TRUE on success, %FALSE on failure
 561  **/
 562 gboolean
 563 g_output_stream_close (GOutputStream  *stream,
 564                        GCancellable   *cancellable,
 565                        GError        **error)
 566 {
 567   gboolean res;
 568
 569   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 570
 571   if (stream->priv->closed)
 572     return TRUE;
 573
 574   if (!g_output_stream_set_pending (stream, error))
 575     return FALSE;
 576
 577   res = _g_output_stream_close_internal (stream, cancellable, error);
 578
 579   g_output_stream_clear_pending (stream);
 580
 581   return res;
 582 }
 583
 584 static void
 585 async_ready_callback_wrapper (GObject      *source_object,
 586                               GAsyncResult *res,
 587                               gpointer      user_data)
 588 {
 589   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 590
 591   g_output_stream_clear_pending (stream);
 592   if (stream->priv->outstanding_callback)
 593     (*stream->priv->outstanding_callback) (source_object, res, user_data);
 594   g_object_unref (stream);
 595 }
 596
 597 typedef struct {
 598   gint io_priority;
 599   GCancellable *cancellable;
 600   GError *flush_error;
 601   gpointer user_data;
 602 } CloseUserData;
 603
 604 static void
 605 async_ready_close_callback_wrapper (GObject      *source_object,
 606                                     GAsyncResult *res,
 607                                     gpointer      user_data)
 608 {
 609   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 610   CloseUserData *data = user_data;
 611
 612   stream->priv->closing = FALSE;
 613   stream->priv->closed = TRUE;
 614
 615   g_output_stream_clear_pending (stream);
 616
 617   if (stream->priv->outstanding_callback)
 618     {
 619       if (data->flush_error != NULL)
 620         {
 621           GSimpleAsyncResult *err;
 622
 623           err = g_simple_async_result_new_take_error (source_object,
 624                                                       stream->priv->outstanding_callback,
 625                                                       data->user_data,
 626                                                       data->flush_error);
 627           data->flush_error = NULL;
 628
 629           (*stream->priv->outstanding_callback) (source_object,
 630                                                  G_ASYNC_RESULT (err),
 631                                                  data->user_data);
 632           g_object_unref (err);
 633         }
 634       else
 635         {
 636           (*stream->priv->outstanding_callback) (source_object,
 637                                                  res,
 638                                                  data->user_data);
 639         }
 640     }
 641
 642   g_object_unref (stream);
 643
 644   if (data->cancellable)
 645     g_object_unref (data->cancellable);
 646
 647   if (data->flush_error)
 648     g_error_free (data->flush_error);
 649
 650   g_slice_free (CloseUserData, data);
 651 }
 652
 653 static void
 654 async_ready_close_flushed_callback_wrapper (GObject      *source_object,
 655                                             GAsyncResult *res,
 656                                             gpointer      user_data)
 657 {
 658   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 659   GOutputStreamClass *class;
 660   CloseUserData *data = user_data;
 661   GSimpleAsyncResult *simple;
 662
 663   /* propagate the possible error */
 664   if (G_IS_SIMPLE_ASYNC_RESULT (res))
 665     {
 666       simple = G_SIMPLE_ASYNC_RESULT (res);
 667       g_simple_async_result_propagate_error (simple, &data->flush_error);
 668     }
 669
 670   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 671
 672   /* we still close, even if there was a flush error */
 673   class->close_async (stream, data->io_priority, data->cancellable,
 674                       async_ready_close_callback_wrapper, user_data);
 675 }
 676
 677 /**
 678  * g_output_stream_write_async:
 679  * @stream: A #GOutputStream.
 680  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 681  * @count: the number of bytes to write
 682  * @io_priority: the io priority of the request.
 683  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 684  * @callback: (scope async): callback to call when the request is satisfied
 685  * @user_data: (closure): the data to pass to callback function
 686  *
 687  * Request an asynchronous write of @count bytes from @buffer into
 688  * the stream. When the operation is finished @callback will be called.
 689  * You can then call g_output_stream_write_finish() to get the result of the
 690  * operation.
 691  *
 692  * During an async request no other sync and async calls are allowed,
 693  * and will result in %G_IO_ERROR_PENDING errors.
 694  *
 695  * A value of @count larger than %G_MAXSSIZE will cause a
 696  * %G_IO_ERROR_INVALID_ARGUMENT error.
 697  *
 698  * On success, the number of bytes written will be passed to the
 699  * @callback. It is not an error if this is not the same as the
 700  * requested size, as it can happen e.g. on a partial I/O error,
 701  * but generally we try to write as many bytes as requested.
 702  *
 703  * You are guaranteed that this method will never fail with
 704  * %G_IO_ERROR_WOULD_BLOCK - if @stream can't accept more data, the
 705  * method will just wait until this changes.
 706  *
 707  * Any outstanding I/O request with higher priority (lower numerical
 708  * value) will be executed before an outstanding request with lower
 709  * priority. Default priority is %G_PRIORITY_DEFAULT.
 710  *
 711  * The asyncronous methods have a default fallback that uses threads
 712  * to implement asynchronicity, so they are optional for inheriting
 713  * classes. However, if you override one you must override all.
 714  *
 715  * For the synchronous, blocking version of this function, see
 716  * g_output_stream_write().
 717  **/
 718 void
 719 g_output_stream_write_async (GOutputStream       *stream,
 720                              const void          *buffer,
 721                              gsize                count,
 722                              int                  io_priority,
 723                              GCancellable        *cancellable,
 724                              GAsyncReadyCallback  callback,
 725                              gpointer             user_data)
 726 {
 727   GOutputStreamClass *class;
 728   GSimpleAsyncResult *simple;
 729   GError *error = NULL;
 730
 731   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 732   g_return_if_fail (buffer != NULL);
 733
 734   if (count == 0)
 735     {
 736       simple = g_simple_async_result_new (G_OBJECT (stream),
 737                                           callback,
 738                                           user_data,
 739                                           g_output_stream_write_async);
 740       g_simple_async_result_complete_in_idle (simple);
 741       g_object_unref (simple);
 742       return;
 743     }
 744
 745   if (((gssize) count) < 0)
 746     {
 747       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 748                                            callback,
 749                                            user_data,
 750                                            G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 751                                            _("Too large count value passed to %s"),
 752                                            G_STRFUNC);
 753       return;
 754     }
 755
 756   if (!g_output_stream_set_pending (stream, &error))
 757     {
 758       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
 759                                             callback,
 760                                             user_data,
 761                                             error);
 762       return;
 763     }
 764
 765   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 766
 767   stream->priv->outstanding_callback = callback;
 768   g_object_ref (stream);
 769   class->write_async (stream, buffer, count, io_priority, cancellable,
 770                       async_ready_callback_wrapper, user_data);
 771 }
 772
 773 /**
 774  * g_output_stream_write_finish:
 775  * @stream: a #GOutputStream.
 776  * @result: a #GAsyncResult.
 777  * @error: a #GError location to store the error occurring, or %NULL to
 778  * ignore.
 779  *
 780  * Finishes a stream write operation.
 781  *
 782  * Returns: a #gssize containing the number of bytes written to the stream.
 783  **/
 784 gssize
 785 g_output_stream_write_finish (GOutputStream  *stream,
 786                               GAsyncResult   *result,
 787                               GError        **error)
 788 {
 789   GSimpleAsyncResult *simple;
 790   GOutputStreamClass *class;
 791
 792   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 793   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
 794
 795   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 796     {
 797       simple = G_SIMPLE_ASYNC_RESULT (result);
 798       if (g_simple_async_result_propagate_error (simple, error))
 799         return -1;
 800
 801       /* Special case writes of 0 bytes */
 802       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_write_async)
 803         return 0;
 804     }
 805
 806   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 807   return class->write_finish (stream, result, error);
 808 }
 809
 810 typedef struct {
 811   GInputStream *source;
 812   gpointer user_data;
 813   GAsyncReadyCallback callback;
 814 } SpliceUserData;
 815
 816 static void
 817 async_ready_splice_callback_wrapper (GObject      *source_object,
 818                                      GAsyncResult *res,
 819                                      gpointer     _data)
 820 {
 821   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 822   SpliceUserData *data = _data;
 823
 824   g_output_stream_clear_pending (stream);
 825
 826   if (data->callback)
 827     (*data->callback) (source_object, res, data->user_data);
 828
 829   g_object_unref (stream);
 830   g_object_unref (data->source);
 831   g_free (data);
 832 }
 833
 834 /**
 835  * g_output_stream_splice_async:
 836  * @stream: a #GOutputStream.
 837  * @source: a #GInputStream.
 838  * @flags: a set of #GOutputStreamSpliceFlags.
 839  * @io_priority: the io priority of the request.
 840  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 841  * @callback: (scope async): a #GAsyncReadyCallback.
 842  * @user_data: (closure): user data passed to @callback.
 843  *
 844  * Splices a stream asynchronously.
 845  * When the operation is finished @callback will be called.
 846  * You can then call g_output_stream_splice_finish() to get the
 847  * result of the operation.
 848  *
 849  * For the synchronous, blocking version of this function, see
 850  * g_output_stream_splice().
 851  **/
 852 void
 853 g_output_stream_splice_async (GOutputStream            *stream,
 854                               GInputStream             *source,
 855                               GOutputStreamSpliceFlags  flags,
 856                               int                       io_priority,
 857                               GCancellable             *cancellable,
 858                               GAsyncReadyCallback       callback,
 859                               gpointer                  user_data)
 860 {
 861   GOutputStreamClass *class;
 862   SpliceUserData *data;
 863   GError *error = NULL;
 864
 865   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 866   g_return_if_fail (G_IS_INPUT_STREAM (source));
 867
 868   if (g_input_stream_is_closed (source))
 869     {
 870       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 871                                            callback,
 872                                            user_data,
 873                                            G_IO_ERROR, G_IO_ERROR_CLOSED,
 874                                            _("Source stream is already closed"));
 875       return;
 876     }
 877
 878   if (!g_output_stream_set_pending (stream, &error))
 879     {
 880       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
 881                                             callback,
 882                                             user_data,
 883                                             error);
 884       return;
 885     }
 886
 887   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 888
 889   data = g_new0 (SpliceUserData, 1);
 890   data->callback = callback;
 891   data->user_data = user_data;
 892   data->source = g_object_ref (source);
 893
 894   g_object_ref (stream);
 895   class->splice_async (stream, source, flags, io_priority, cancellable,
 896                       async_ready_splice_callback_wrapper, data);
 897 }
 898
 899 /**
 900  * g_output_stream_splice_finish:
 901  * @stream: a #GOutputStream.
 902  * @result: a #GAsyncResult.
 903  * @error: a #GError location to store the error occurring, or %NULL to
 904  * ignore.
 905  *
 906  * Finishes an asynchronous stream splice operation.
 907  *
 908  * Returns: a #gssize of the number of bytes spliced. Note that if the
 909  *     number of bytes spliced is greater than %G_MAXSSIZE, then that
 910  *     will be returned, and there is no way to determine the actual
 911  *     number of bytes spliced.
 912  **/
 913 gssize
 914 g_output_stream_splice_finish (GOutputStream  *stream,
 915                                GAsyncResult   *result,
 916                                GError        **error)
 917 {
 918   GSimpleAsyncResult *simple;
 919   GOutputStreamClass *class;
 920
 921   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 922   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
 923
 924   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 925     {
 926       simple = G_SIMPLE_ASYNC_RESULT (result);
 927       if (g_simple_async_result_propagate_error (simple, error))
 928         return -1;
 929     }
 930
 931   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 932   return class->splice_finish (stream, result, error);
 933 }
 934
 935 /**
 936  * g_output_stream_flush_async:
 937  * @stream: a #GOutputStream.
 938  * @io_priority: the io priority of the request.
 939  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 940  * @callback: (scope async): a #GAsyncReadyCallback to call when the request is satisfied
 941  * @user_data: (closure): the data to pass to callback function
 942  *
 943  * Forces an asynchronous write of all user-space buffered data for
 944  * the given @stream.
 945  * For behaviour details see g_output_stream_flush().
 946  *
 947  * When the operation is finished @callback will be
 948  * called. You can then call g_output_stream_flush_finish() to get the
 949  * result of the operation.
 950  **/
 951 void
 952 g_output_stream_flush_async (GOutputStream       *stream,
 953                              int                  io_priority,
 954                              GCancellable        *cancellable,
 955                              GAsyncReadyCallback  callback,
 956                              gpointer             user_data)
 957 {
 958   GOutputStreamClass *class;
 959   GSimpleAsyncResult *simple;
 960   GError *error = NULL;
 961
 962   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 963
 964   if (!g_output_stream_set_pending (stream, &error))
 965     {
 966       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
 967                                             callback,
 968                                             user_data,
 969                                             error);
 970       return;
 971     }
 972
 973   stream->priv->outstanding_callback = callback;
 974   g_object_ref (stream);
 975
 976   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 977
 978   if (class->flush_async == NULL)
 979     {
 980       simple = g_simple_async_result_new (G_OBJECT (stream),
 981                                           async_ready_callback_wrapper,
 982                                           user_data,
 983                                           g_output_stream_flush_async);
 984       g_simple_async_result_complete_in_idle (simple);
 985       g_object_unref (simple);
 986       return;
 987     }
 988
 989   class->flush_async (stream, io_priority, cancellable,
 990                       async_ready_callback_wrapper, user_data);
 991 }
 992
 993 /**
 994  * g_output_stream_flush_finish:
 995  * @stream: a #GOutputStream.
 996  * @result: a GAsyncResult.
 997  * @error: a #GError location to store the error occurring, or %NULL to
 998  * ignore.
 999  *
1000  * Finishes flushing an output stream.
1001  *
1002  * Returns: %TRUE if flush operation succeeded, %FALSE otherwise.
1003  **/
1004 gboolean
1005 g_output_stream_flush_finish (GOutputStream  *stream,
1006                               GAsyncResult   *result,
1007                               GError        **error)
1008 {
1009   GSimpleAsyncResult *simple;
1010   GOutputStreamClass *klass;
1011
1012   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1013   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
1014
1015   if (G_IS_SIMPLE_ASYNC_RESULT (result))
1016     {
1017       simple = G_SIMPLE_ASYNC_RESULT (result);
1018       if (g_simple_async_result_propagate_error (simple, error))
1019         return FALSE;
1020
1021       /* Special case default implementation */
1022       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_flush_async)
1023         return TRUE;
1024     }
1025
1026   klass = G_OUTPUT_STREAM_GET_CLASS (stream);
1027   return klass->flush_finish (stream, result, error);
1028 }
1029
1030
1031 /**
1032  * g_output_stream_close_async:
1033  * @stream: A #GOutputStream.
1034  * @io_priority: the io priority of the request.
1035  * @cancellable: (allow-none): optional cancellable object
1036  * @callback: (scope async): callback to call when the request is satisfied
1037  * @user_data: (closure): the data to pass to callback function
1038  *
1039  * Requests an asynchronous close of the stream, releasing resources
1040  * related to it. When the operation is finished @callback will be
1041  * called. You can then call g_output_stream_close_finish() to get
1042  * the result of the operation.
1043  *
1044  * For behaviour details see g_output_stream_close().
1045  *
1046  * The asyncronous methods have a default fallback that uses threads
1047  * to implement asynchronicity, so they are optional for inheriting
1048  * classes. However, if you override one you must override all.
1049  **/
1050 void
1051 g_output_stream_close_async (GOutputStream       *stream,
1052                              int                  io_priority,
1053                              GCancellable        *cancellable,
1054                              GAsyncReadyCallback  callback,
1055                              gpointer             user_data)
1056 {
1057   GOutputStreamClass *class;
1058   GSimpleAsyncResult *simple;
1059   GError *error = NULL;
1060   CloseUserData *data;
1061
1062   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1063
1064   if (stream->priv->closed)
1065     {
1066       simple = g_simple_async_result_new (G_OBJECT (stream),
1067                                           callback,
1068                                           user_data,
1069                                           g_output_stream_close_async);
1070       g_simple_async_result_complete_in_idle (simple);
1071       g_object_unref (simple);
1072       return;
1073     }
1074
1075   if (!g_output_stream_set_pending (stream, &error))
1076     {
1077       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
1078                                             callback,
1079                                             user_data,
1080                                             error);
1081       return;
1082     }
1083
1084   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1085   stream->priv->closing = TRUE;
1086   stream->priv->outstanding_callback = callback;
1087   g_object_ref (stream);
1088
1089   data = g_slice_new0 (CloseUserData);
1090
1091   if (cancellable != NULL)
1092     data->cancellable = g_object_ref (cancellable);
1093
1094   data->io_priority = io_priority;
1095   data->user_data = user_data;
1096
1097   /* Call close_async directly if there is no need to flush, or if the flush
1098      can be done sync (in the output stream async close thread) */
1099   if (class->flush_async == NULL ||
1100       (class->flush_async == g_output_stream_real_flush_async &&
1101        (class->flush == NULL || class->close_async == g_output_stream_real_close_async)))
1102     {
1103       class->close_async (stream, io_priority, cancellable,
1104                           async_ready_close_callback_wrapper, data);
1105     }
1106   else
1107     {
1108       /* First do an async flush, then do the async close in the callback
1109          wrapper (see async_ready_close_flushed_callback_wrapper) */
1110       class->flush_async (stream, io_priority, cancellable,
1111                           async_ready_close_flushed_callback_wrapper, data);
1112     }
1113 }
1114
1115 /**
1116  * g_output_stream_close_finish:
1117  * @stream: a #GOutputStream.
1118  * @result: a #GAsyncResult.
1119  * @error: a #GError location to store the error occurring, or %NULL to
1120  * ignore.
1121  *
1122  * Closes an output stream.
1123  *
1124  * Returns: %TRUE if stream was successfully closed, %FALSE otherwise.
1125  **/
1126 gboolean
1127 g_output_stream_close_finish (GOutputStream  *stream,
1128                               GAsyncResult   *result,
1129                               GError        **error)
1130 {
1131   GSimpleAsyncResult *simple;
1132   GOutputStreamClass *class;
1133
1134   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1135   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
1136
1137   if (G_IS_SIMPLE_ASYNC_RESULT (result))
1138     {
1139       simple = G_SIMPLE_ASYNC_RESULT (result);
1140       if (g_simple_async_result_propagate_error (simple, error))
1141         return FALSE;
1142
1143       /* Special case already closed */
1144       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_close_async)
1145         return TRUE;
1146     }
1147
1148   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1149   return class->close_finish (stream, result, error);
1150 }
1151
1152 /**
1153  * g_output_stream_is_closed:
1154  * @stream: a #GOutputStream.
1155  *
1156  * Checks if an output stream has already been closed.
1157  *
1158  * Returns: %TRUE if @stream is closed. %FALSE otherwise.
1159  **/
1160 gboolean
1161 g_output_stream_is_closed (GOutputStream *stream)
1162 {
1163   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
1164
1165   return stream->priv->closed;
1166 }
1167
1168 /**
1169  * g_output_stream_is_closing:
1170  * @stream: a #GOutputStream.
1171  *
1172  * Checks if an output stream is being closed. This can be
1173  * used inside e.g. a flush implementation to see if the
1174  * flush (or other i/o operation) is called from within
1175  * the closing operation.
1176  *
1177  * Returns: %TRUE if @stream is being closed. %FALSE otherwise.
1178  *
1179  * Since: 2.24
1180  **/
1181 gboolean
1182 g_output_stream_is_closing (GOutputStream *stream)
1183 {
1184   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
1185
1186   return stream->priv->closing;
1187 }
1188
1189 /**
1190  * g_output_stream_has_pending:
1191  * @stream: a #GOutputStream.
1192  *
1193  * Checks if an ouput stream has pending actions.
1194  *
1195  * Returns: %TRUE if @stream has pending actions.
1196  **/
1197 gboolean
1198 g_output_stream_has_pending (GOutputStream *stream)
1199 {
1200   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1201
1202   return stream->priv->pending;
1203 }
1204
1205 /**
1206  * g_output_stream_set_pending:
1207  * @stream: a #GOutputStream.
1208  * @error: a #GError location to store the error occurring, or %NULL to
1209  * ignore.
1210  *
1211  * Sets @stream to have actions pending. If the pending flag is
1212  * already set or @stream is closed, it will return %FALSE and set
1213  * @error.
1214  *
1215  * Return value: %TRUE if pending was previously unset and is now set.
1216  **/
1217 gboolean
1218 g_output_stream_set_pending (GOutputStream *stream,
1219                              GError **error)
1220 {
1221   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1222
1223   if (stream->priv->closed)
1224     {
1225       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
1226                            _("Stream is already closed"));
1227       return FALSE;
1228     }
1229
1230   if (stream->priv->pending)
1231     {
1232       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PENDING,
1233                            /* Translators: This is an error you get if there is
1234                             * already an operation running against this stream when
1235                             * you try to start one */
1236                            _("Stream has outstanding operation"));
1237       return FALSE;
1238     }
1239
1240   stream->priv->pending = TRUE;
1241   return TRUE;
1242 }
1243
1244 /**
1245  * g_output_stream_clear_pending:
1246  * @stream: output stream
1247  *
1248  * Clears the pending flag on @stream.
1249  **/
1250 void
1251 g_output_stream_clear_pending (GOutputStream *stream)
1252 {
1253   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1254
1255   stream->priv->pending = FALSE;
1256 }
1257
1258
1259 /********************************************
1260  *   Default implementation of async ops    *
1261  ********************************************/
1262
1263 typedef struct {
1264   const void         *buffer;
1265   gsize               count_requested;
1266   gssize              count_written;
1267 } WriteData;
1268
1269 static void
1270 write_async_thread (GSimpleAsyncResult *res,
1271                     GObject            *object,
1272                     GCancellable       *cancellable)
1273 {
1274   WriteData *op;
1275   GOutputStreamClass *class;
1276   GError *error = NULL;
1277
1278   class = G_OUTPUT_STREAM_GET_CLASS (object);
1279   op = g_simple_async_result_get_op_res_gpointer (res);
1280   op->count_written = class->write_fn (G_OUTPUT_STREAM (object), op->buffer, op->count_requested,
1281                                        cancellable, &error);
1282   if (op->count_written == -1)
1283     g_simple_async_result_take_error (res, error);
1284 }
1285
1286 static void
1287 g_output_stream_real_write_async (GOutputStream       *stream,
1288                                   const void          *buffer,
1289                                   gsize                count,
1290                                   int                  io_priority,
1291                                   GCancellable        *cancellable,
1292                                   GAsyncReadyCallback  callback,
1293                                   gpointer             user_data)
1294 {
1295   GSimpleAsyncResult *res;
1296   WriteData *op;
1297
1298   op = g_new0 (WriteData, 1);
1299   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1300   g_simple_async_result_set_op_res_gpointer (res, op, g_free);
1301   op->buffer = buffer;
1302   op->count_requested = count;
1303
1304   g_simple_async_result_run_in_thread (res, write_async_thread, io_priority, cancellable);
1305   g_object_unref (res);
1306 }
1307
1308 static gssize
1309 g_output_stream_real_write_finish (GOutputStream  *stream,
1310                                    GAsyncResult   *result,
1311                                    GError        **error)
1312 {
1313   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1314   WriteData *op;
1315
1316   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_write_async);
1317   op = g_simple_async_result_get_op_res_gpointer (simple);
1318   return op->count_written;
1319 }
1320
1321 typedef struct {
1322   GInputStream *source;
1323   GOutputStreamSpliceFlags flags;
1324   gssize bytes_copied;
1325 } SpliceData;
1326
1327 static void
1328 splice_async_thread (GSimpleAsyncResult *result,
1329                      GObject            *object,
1330                      GCancellable       *cancellable)
1331 {
1332   SpliceData *op;
1333   GOutputStreamClass *class;
1334   GError *error = NULL;
1335   GOutputStream *stream;
1336
1337   stream = G_OUTPUT_STREAM (object);
1338   class = G_OUTPUT_STREAM_GET_CLASS (object);
1339   op = g_simple_async_result_get_op_res_gpointer (result);
1340
1341   op->bytes_copied = class->splice (stream,
1342                                     op->source,
1343                                     op->flags,
1344                                     cancellable,
1345                                     &error);
1346   if (op->bytes_copied == -1)
1347     g_simple_async_result_take_error (result, error);
1348 }
1349
1350 static void
1351 g_output_stream_real_splice_async (GOutputStream             *stream,
1352                                    GInputStream              *source,
1353                                    GOutputStreamSpliceFlags   flags,
1354                                    int                        io_priority,
1355                                    GCancellable              *cancellable,
1356                                    GAsyncReadyCallback        callback,
1357                                    gpointer                   user_data)
1358 {
1359   GSimpleAsyncResult *res;
1360   SpliceData *op;
1361
1362   op = g_new0 (SpliceData, 1);
1363   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_splice_async);
1364   g_simple_async_result_set_op_res_gpointer (res, op, g_free);
1365   op->flags = flags;
1366   op->source = source;
1367
1368   /* TODO: In the case where both source and destintion have
1369      non-threadbased async calls we can use a true async copy here */
1370
1371   g_simple_async_result_run_in_thread (res, splice_async_thread, io_priority, cancellable);
1372   g_object_unref (res);
1373 }
1374
1375 static gssize
1376 g_output_stream_real_splice_finish (GOutputStream  *stream,
1377                                     GAsyncResult   *result,
1378                                     GError        **error)
1379 {
1380   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1381   SpliceData *op;
1382
1383   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_splice_async);
1384   op = g_simple_async_result_get_op_res_gpointer (simple);
1385   return op->bytes_copied;
1386 }
1387
1388
1389 static void
1390 flush_async_thread (GSimpleAsyncResult *res,
1391                     GObject            *object,
1392                     GCancellable       *cancellable)
1393 {
1394   GOutputStreamClass *class;
1395   gboolean result;
1396   GError *error = NULL;
1397
1398   class = G_OUTPUT_STREAM_GET_CLASS (object);
1399   result = TRUE;
1400   if (class->flush)
1401     result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error);
1402
1403   if (!result)
1404     g_simple_async_result_take_error (res, error);
1405 }
1406
1407 static void
1408 g_output_stream_real_flush_async (GOutputStream       *stream,
1409                                   int                  io_priority,
1410                                   GCancellable        *cancellable,
1411                                   GAsyncReadyCallback  callback,
1412                                   gpointer             user_data)
1413 {
1414   GSimpleAsyncResult *res;
1415
1416   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1417
1418   g_simple_async_result_run_in_thread (res, flush_async_thread, io_priority, cancellable);
1419   g_object_unref (res);
1420 }
1421
1422 static gboolean
1423 g_output_stream_real_flush_finish (GOutputStream  *stream,
1424                                    GAsyncResult   *result,
1425                                    GError        **error)
1426 {
1427   return TRUE;
1428 }
1429
1430 static void
1431 close_async_thread (GSimpleAsyncResult *res,
1432                     GObject            *object,
1433                     GCancellable       *cancellable)
1434 {
1435   GOutputStreamClass *class;
1436   GError *error = NULL;
1437   gboolean result = TRUE;
1438
1439   class = G_OUTPUT_STREAM_GET_CLASS (object);
1440
1441   /* Do a flush here if there is a flush function, and we did not have to do
1442      an async flush before (see g_output_stream_close_async) */
1443   if (class->flush != NULL &&
1444       (class->flush_async == NULL ||
1445        class->flush_async == g_output_stream_real_flush_async))
1446     {
1447       result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error);
1448     }
1449
1450   /* Auto handling of cancelation disabled, and ignore
1451      cancellation, since we want to close things anyway, although
1452      possibly in a quick-n-dirty way. At least we never want to leak
1453      open handles */
1454
1455   if (class->close_fn)
1456     {
1457       /* Make sure to close, even if the flush failed (see sync close) */
1458       if (!result)
1459         class->close_fn (G_OUTPUT_STREAM (object), cancellable, NULL);
1460       else
1461         result = class->close_fn (G_OUTPUT_STREAM (object), cancellable, &error);
1462
1463       if (!result)
1464         g_simple_async_result_take_error (res, error);
1465     }
1466 }
1467
1468 static void
1469 g_output_stream_real_close_async (GOutputStream       *stream,
1470                                   int                  io_priority,
1471                                   GCancellable        *cancellable,
1472                                   GAsyncReadyCallback  callback,
1473                                   gpointer             user_data)
1474 {
1475   GSimpleAsyncResult *res;
1476
1477   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_close_async);
1478
1479   g_simple_async_result_set_handle_cancellation (res, FALSE);
1480
1481   g_simple_async_result_run_in_thread (res, close_async_thread, io_priority, cancellable);
1482   g_object_unref (res);
1483 }
1484
1485 static gboolean
1486 g_output_stream_real_close_finish (GOutputStream  *stream,
1487                                    GAsyncResult   *result,
1488                                    GError        **error)
1489 {
1490   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1491   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_close_async);
1492   return TRUE;
1493 }