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