goutputstream.c 58.6 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
/* GIO - GLib Input, Output and Streaming Library
 * 
 * Copyright (C) 2006-2007 Red Hat, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General
 * Public License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * Author: Alexander Larsson <alexl@redhat.com>
 */

23
#include "config.h"
24
#include "goutputstream.h"
25 26
#include "gcancellable.h"
#include "gasyncresult.h"
27
#include "gtask.h"
28 29
#include "ginputstream.h"
#include "gioerror.h"
30
#include "gioprivate.h"
31
#include "glibintl.h"
32
#include "gpollableoutputstream.h"
33

34 35
/**
 * SECTION:goutputstream
Matthias Clasen's avatar
Matthias Clasen committed
36
 * @short_description: Base class for implementing streaming output
Matthias Clasen's avatar
Matthias Clasen committed
37
 * @include: gio/gio.h
38
 *
Dan Winship's avatar
Dan Winship committed
39
 * #GOutputStream has functions to write to a stream (g_output_stream_write()),
Matthias Clasen's avatar
Matthias Clasen committed
40 41
 * to close a stream (g_output_stream_close()) and to flush pending writes
 * (g_output_stream_flush()). 
42
 *
Matthias Clasen's avatar
Matthias Clasen committed
43 44 45 46
 * To copy the content of an input stream to an output stream without 
 * manually handling the reads and writes, use g_output_stream_splice(). 
 *
 * All of these functions have async variants too.
47 48
 **/

49 50 51
struct _GOutputStreamPrivate {
  guint closed : 1;
  guint pending : 1;
52
  guint closing : 1;
53 54 55
  GAsyncReadyCallback outstanding_callback;
};

56 57
G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GOutputStream, g_output_stream, G_TYPE_OBJECT)

58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98
static gssize   g_output_stream_real_splice        (GOutputStream             *stream,
						    GInputStream              *source,
						    GOutputStreamSpliceFlags   flags,
						    GCancellable              *cancellable,
						    GError                   **error);
static void     g_output_stream_real_write_async   (GOutputStream             *stream,
						    const void                *buffer,
						    gsize                      count,
						    int                        io_priority,
						    GCancellable              *cancellable,
						    GAsyncReadyCallback        callback,
						    gpointer                   data);
static gssize   g_output_stream_real_write_finish  (GOutputStream             *stream,
						    GAsyncResult              *result,
						    GError                   **error);
static void     g_output_stream_real_splice_async  (GOutputStream             *stream,
						    GInputStream              *source,
						    GOutputStreamSpliceFlags   flags,
						    int                        io_priority,
						    GCancellable              *cancellable,
						    GAsyncReadyCallback        callback,
						    gpointer                   data);
static gssize   g_output_stream_real_splice_finish (GOutputStream             *stream,
						    GAsyncResult              *result,
						    GError                   **error);
static void     g_output_stream_real_flush_async   (GOutputStream             *stream,
						    int                        io_priority,
						    GCancellable              *cancellable,
						    GAsyncReadyCallback        callback,
						    gpointer                   data);
static gboolean g_output_stream_real_flush_finish  (GOutputStream             *stream,
						    GAsyncResult              *result,
						    GError                   **error);
static void     g_output_stream_real_close_async   (GOutputStream             *stream,
						    int                        io_priority,
						    GCancellable              *cancellable,
						    GAsyncReadyCallback        callback,
						    gpointer                   data);
static gboolean g_output_stream_real_close_finish  (GOutputStream             *stream,
						    GAsyncResult              *result,
						    GError                   **error);
99
static gboolean g_output_stream_internal_close     (GOutputStream             *stream,
100 101
                                                    GCancellable              *cancellable,
                                                    GError                   **error);
102 103 104 105 106 107 108 109
static void     g_output_stream_internal_close_async (GOutputStream           *stream,
                                                      int                      io_priority,
                                                      GCancellable            *cancellable,
                                                      GAsyncReadyCallback      callback,
                                                      gpointer                 data);
static gboolean g_output_stream_internal_close_finish (GOutputStream          *stream,
                                                       GAsyncResult           *result,
                                                       GError                **error);
110 111 112 113 114 115 116 117 118 119

static void
g_output_stream_dispose (GObject *object)
{
  GOutputStream *stream;

  stream = G_OUTPUT_STREAM (object);
  
  if (!stream->priv->closed)
    g_output_stream_close (stream, NULL, NULL);
120 121

  G_OBJECT_CLASS (g_output_stream_parent_class)->dispose (object);
122 123 124 125 126 127
}

static void
g_output_stream_class_init (GOutputStreamClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
128

129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145
  gobject_class->dispose = g_output_stream_dispose;

  klass->splice = g_output_stream_real_splice;
  
  klass->write_async = g_output_stream_real_write_async;
  klass->write_finish = g_output_stream_real_write_finish;
  klass->splice_async = g_output_stream_real_splice_async;
  klass->splice_finish = g_output_stream_real_splice_finish;
  klass->flush_async = g_output_stream_real_flush_async;
  klass->flush_finish = g_output_stream_real_flush_finish;
  klass->close_async = g_output_stream_real_close_async;
  klass->close_finish = g_output_stream_real_close_finish;
}

static void
g_output_stream_init (GOutputStream *stream)
{
146
  stream->priv = g_output_stream_get_instance_private (stream);
147 148 149 150 151
}

/**
 * g_output_stream_write:
 * @stream: a #GOutputStream.
152
 * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write. 
153
 * @count: the number of bytes to write
154
 * @cancellable: (allow-none): optional cancellable object
Matthias Clasen's avatar
Matthias Clasen committed
155
 * @error: location to store the error occurring, or %NULL to ignore
156 157 158 159
 *
 * Tries to write @count bytes from @buffer into the stream. Will block
 * during the operation.
 * 
160
 * If count is 0, returns 0 and does nothing. A value of @count
161 162 163 164
 * larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
 *
 * On success, the number of bytes written to the stream is returned.
 * It is not an error if this is not the same as the requested size, as it
165 166 167 168
 * can happen e.g. on a partial I/O error, or if there is not enough
 * storage in the stream. All writes block until at least one byte
 * is written or an error occurs; 0 is never returned (unless
 * @count is 0).
169
 * 
Dan Winship's avatar
Dan Winship committed
170
 * If @cancellable is not %NULL, then the operation can be cancelled by
171
 * triggering the cancellable object from another thread. If the operation
172
 * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an
173 174 175 176 177
 * operation was partially finished when the operation was cancelled the
 * partial result will be returned, without an error.
 *
 * On error -1 is returned and @error is set accordingly.
 * 
178 179
 * Virtual: write_fn
 *
180 181 182
 * Return value: Number of bytes written, or -1 on error
 **/
gssize
183 184 185 186 187
g_output_stream_write (GOutputStream  *stream,
		       const void     *buffer,
		       gsize           count,
		       GCancellable   *cancellable,
		       GError        **error)
188 189 190 191 192 193 194 195 196 197 198 199 200
{
  GOutputStreamClass *class;
  gssize res;

  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
  g_return_val_if_fail (buffer != NULL, 0);

  if (count == 0)
    return 0;
  
  if (((gssize) count) < 0)
    {
      g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
201
		   _("Too large count value passed to %s"), G_STRFUNC);
202 203 204 205 206
      return -1;
    }

  class = G_OUTPUT_STREAM_GET_CLASS (stream);

207
  if (class->write_fn == NULL) 
208
    {
209 210
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
                           _("Output stream doesn't implement write"));
211 212 213
      return -1;
    }
  
214 215 216
  if (!g_output_stream_set_pending (stream, error))
    return -1;
  
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
  
225 226
  g_output_stream_clear_pending (stream);

227 228 229 230 231 232
  return res; 
}

/**
 * g_output_stream_write_all:
 * @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.
Matthias Clasen's avatar
Matthias Clasen committed
238
 * @error: location to store the error occurring, or %NULL to ignore
239 240 241 242 243 244 245 246 247 248
 *
 * Tries to write @count bytes from @buffer into the stream. Will block
 * during the operation.
 * 
 * This function is similar to g_output_stream_write(), except it tries to
 * write as many bytes as requested, only stopping on an error.
 *
 * On a successful write of @count bytes, %TRUE is returned, and @bytes_written
 * is set to @count.
 * 
Dan Winship's avatar
Dan Winship committed
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.
252 253 254 255
 *
 * Return value: %TRUE on success, %FALSE if there was an error
 **/
gboolean
256 257 258 259 260 261
g_output_stream_write_all (GOutputStream  *stream,
			   const void     *buffer,
			   gsize           count,
			   gsize          *bytes_written,
			   GCancellable   *cancellable,
			   GError        **error)
262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288
{
  gsize _bytes_written;
  gssize res;

  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
  g_return_val_if_fail (buffer != NULL, FALSE);

  _bytes_written = 0;
  while (_bytes_written < count)
    {
      res = g_output_stream_write (stream, (char *)buffer + _bytes_written, count - _bytes_written,
				   cancellable, error);
      if (res == -1)
	{
	  if (bytes_written)
	    *bytes_written = _bytes_written;
	  return FALSE;
	}
      
      if (res == 0)
	g_warning ("Write returned zero without error");

      _bytes_written += res;
    }
  
  if (bytes_written)
    *bytes_written = _bytes_written;
289

290 291 292
  return TRUE;
}

293 294 295 296 297 298 299
/**
 * g_output_stream_write_bytes:
 * @stream: a #GOutputStream.
 * @bytes: the #GBytes to write
 * @cancellable: (allow-none): optional cancellable object
 * @error: location to store the error occurring, or %NULL to ignore
 *
300 301 302 303 304 305 306 307 308 309 310 311
 * A wrapper function for g_output_stream_write() which takes a
 * #GBytes as input.  This can be more convenient for use by language
 * bindings or in other cases where the refcounted nature of #GBytes
 * is helpful over a bare pointer interface.
 *
 * However, note that this function <emphasis>may</emphasis> still
 * perform partial writes, just like g_output_stream_write().  If that
 * occurs, to continue writing, you will need to create a new #GBytes
 * containing just the remaining bytes, using
 * g_bytes_new_from_bytes().  Passing the same #GBytes instance
 * multiple times potentially can result in duplicated data in the
 * output stream.
312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331
 *
 * Return value: Number of bytes written, or -1 on error
 **/
gssize
g_output_stream_write_bytes (GOutputStream  *stream,
			     GBytes         *bytes,
			     GCancellable   *cancellable,
			     GError        **error)
{
  gsize size;
  gconstpointer data;

  data = g_bytes_get_data (bytes, &size);

  return g_output_stream_write (stream,
                                data, size,
				cancellable,
				error);
}

332 333 334
/**
 * g_output_stream_flush:
 * @stream: a #GOutputStream.
335
 * @cancellable: (allow-none): optional cancellable object
Matthias Clasen's avatar
Matthias Clasen committed
336
 * @error: location to store the error occurring, or %NULL to ignore
337
 *
338 339 340
 * Forces a write of all user-space buffered data for the given
 * @stream. Will block during the operation. Closing the stream will
 * implicitly cause a flush.
341 342 343
 *
 * This function is optional for inherited classes.
 * 
344
 * If @cancellable is not %NULL, then the operation can be cancelled by
345
 * triggering the cancellable object from another thread. If the operation
346
 * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
347
 *
348
 * Return value: %TRUE on success, %FALSE on error
349 350
 **/
gboolean
351 352 353
g_output_stream_flush (GOutputStream  *stream,
                       GCancellable   *cancellable,
                       GError        **error)
354 355 356 357 358 359
{
  GOutputStreamClass *class;
  gboolean res;

  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);

360 361
  if (!g_output_stream_set_pending (stream, error))
    return FALSE;
362 363 364 365 366 367 368
  
  class = G_OUTPUT_STREAM_GET_CLASS (stream);

  res = TRUE;
  if (class->flush)
    {
      if (cancellable)
369
	g_cancellable_push_current (cancellable);
370 371 372 373
      
      res = class->flush (stream, cancellable, error);
      
      if (cancellable)
374
	g_cancellable_pop_current (cancellable);
375 376
    }
  
377 378
  g_output_stream_clear_pending (stream);

379 380 381 382 383
  return res;
}

/**
 * g_output_stream_splice:
384 385 386
 * @stream: a #GOutputStream.
 * @source: a #GInputStream.
 * @flags: a set of #GOutputStreamSpliceFlags.
387
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
Matthias Clasen's avatar
Matthias Clasen committed
388
 * @error: a #GError location to store the error occurring, or %NULL to
389 390
 * ignore.
 *
391
 * Splices an input stream into an output stream.
392
 *
393
 * Returns: a #gssize containing the size of the data spliced, or
394 395 396 397
 *     -1 if an error occurred. Note that if the number of bytes
 *     spliced is greater than %G_MAXSSIZE, then that will be
 *     returned, and there is no way to determine the actual number
 *     of bytes spliced.
398 399
 **/
gssize
400 401 402 403 404
g_output_stream_splice (GOutputStream             *stream,
			GInputStream              *source,
			GOutputStreamSpliceFlags   flags,
			GCancellable              *cancellable,
			GError                   **error)
405 406
{
  GOutputStreamClass *class;
407
  gssize bytes_copied;
408 409 410 411 412 413

  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
  g_return_val_if_fail (G_IS_INPUT_STREAM (source), -1);

  if (g_input_stream_is_closed (source))
    {
414 415
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
                           _("Source stream is already closed"));
416 417 418
      return -1;
    }

419 420
  if (!g_output_stream_set_pending (stream, error))
    return -1;
421

422 423 424
  class = G_OUTPUT_STREAM_GET_CLASS (stream);

  if (cancellable)
425
    g_cancellable_push_current (cancellable);
426 427 428

  bytes_copied = class->splice (stream, source, flags, cancellable, error);

429
  if (cancellable)
430
    g_cancellable_pop_current (cancellable);
431

432 433
  g_output_stream_clear_pending (stream);

434
  return bytes_copied;
435 436 437
}

static gssize
438 439 440 441 442
g_output_stream_real_splice (GOutputStream             *stream,
                             GInputStream              *source,
                             GOutputStreamSpliceFlags   flags,
                             GCancellable              *cancellable,
                             GError                   **error)
443
{
444
  GOutputStreamClass *class = G_OUTPUT_STREAM_GET_CLASS (stream);
445
  gssize n_read, n_written;
446
  gsize bytes_copied;
447 448 449
  char buffer[8192], *p;
  gboolean res;

450
  bytes_copied = 0;
451
  if (class->write_fn == NULL)
452
    {
453 454
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
                           _("Output stream doesn't implement write"));
455 456 457
      res = FALSE;
      goto notsupported;
    }
458

459
  res = TRUE;
460
  do
461 462 463 464 465 466 467
    {
      n_read = g_input_stream_read (source, buffer, sizeof (buffer), cancellable, error);
      if (n_read == -1)
	{
	  res = FALSE;
	  break;
	}
468

469 470 471 472 473 474
      if (n_read == 0)
	break;

      p = buffer;
      while (n_read > 0)
	{
475
	  n_written = class->write_fn (stream, p, n_read, cancellable, error);
476 477 478 479 480 481 482 483 484 485
	  if (n_written == -1)
	    {
	      res = FALSE;
	      break;
	    }

	  p += n_written;
	  n_read -= n_written;
	  bytes_copied += n_written;
	}
486 487 488

      if (bytes_copied > G_MAXSSIZE)
	bytes_copied = G_MAXSSIZE;
489 490 491
    }
  while (res);

492
 notsupported:
493 494 495
  if (!res)
    error = NULL; /* Ignore further errors */

496
  if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_SOURCE)
497 498 499 500 501
    {
      /* Don't care about errors in source here */
      g_input_stream_close (source, cancellable, NULL);
    }

502
  if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET)
503 504
    {
      /* But write errors on close are bad! */
505
      res = g_output_stream_internal_close (stream, cancellable, error);
506 507 508 509
    }

  if (res)
    return bytes_copied;
510

511 512 513
  return -1;
}

514 515 516
/* Must always be called inside
 * g_output_stream_set_pending()/g_output_stream_clear_pending(). */
static gboolean
517 518 519
g_output_stream_internal_close (GOutputStream  *stream,
                                GCancellable   *cancellable,
                                GError        **error)
520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561
{
  GOutputStreamClass *class;
  gboolean res;

  if (stream->priv->closed)
    return TRUE;

  class = G_OUTPUT_STREAM_GET_CLASS (stream);

  stream->priv->closing = TRUE;

  if (cancellable)
    g_cancellable_push_current (cancellable);

  if (class->flush)
    res = class->flush (stream, cancellable, error);
  else
    res = TRUE;

  if (!res)
    {
      /* flushing caused the error that we want to return,
       * but we still want to close the underlying stream if possible
       */
      if (class->close_fn)
        class->close_fn (stream, cancellable, NULL);
    }
  else
    {
      res = TRUE;
      if (class->close_fn)
        res = class->close_fn (stream, cancellable, error);
    }

  if (cancellable)
    g_cancellable_pop_current (cancellable);

  stream->priv->closing = FALSE;
  stream->priv->closed = TRUE;

  return res;
}
562 563 564 565

/**
 * g_output_stream_close:
 * @stream: A #GOutputStream.
566
 * @cancellable: (allow-none): optional cancellable object
Matthias Clasen's avatar
Matthias Clasen committed
567
 * @error: location to store the error occurring, or %NULL to ignore
568 569 570 571 572 573 574 575 576 577
 *
 * Closes the stream, releasing resources related to it.
 *
 * Once the stream is closed, all other operations will return %G_IO_ERROR_CLOSED.
 * Closing a stream multiple times will not return an error.
 *
 * Closing a stream will automatically flush any outstanding buffers in the
 * stream.
 *
 * Streams will be automatically closed when the last reference
578 579
 * is dropped, but you might want to call this function to make sure 
 * resources are released as early as possible.
580 581 582 583 584 585 586
 *
 * Some streams might keep the backing store of the stream (e.g. a file descriptor)
 * open after the stream is closed. See the documentation for the individual
 * stream for details.
 *
 * On failure the first error that happened will be reported, but the close
 * operation will finish as much as possible. A stream that failed to
587
 * close will still return %G_IO_ERROR_CLOSED for all operations. Still, it
588 589 590
 * is important to check and report the error to the user, otherwise
 * there might be a loss of data as all data might not be written.
 * 
Dan Winship's avatar
Dan Winship committed
591
 * If @cancellable is not %NULL, then the operation can be cancelled by
592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612
 * triggering the cancellable object from another thread. If the operation
 * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 * Cancelling a close will still leave the stream closed, but there some streams
 * can use a faster close that doesn't block to e.g. check errors. On
 * cancellation (as with any error) there is no guarantee that all written
 * data will reach the target. 
 *
 * Return value: %TRUE on success, %FALSE on failure
 **/
gboolean
g_output_stream_close (GOutputStream  *stream,
		       GCancellable   *cancellable,
		       GError        **error)
{
  gboolean res;

  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);

  if (stream->priv->closed)
    return TRUE;

613 614
  if (!g_output_stream_set_pending (stream, error))
    return FALSE;
615

616
  res = g_output_stream_internal_close (stream, cancellable, error);
617

618
  g_output_stream_clear_pending (stream);
619 620 621 622 623
  
  return res;
}

static void
624
async_ready_write_callback_wrapper (GObject      *source_object,
625 626
                                    GAsyncResult *res,
                                    gpointer      user_data)
627 628 629
{
  GOutputStream *stream = G_OUTPUT_STREAM (source_object);
  GOutputStreamClass *class;
630 631 632
  GTask *task = user_data;
  gssize nwrote;
  GError *error = NULL;
633

634 635 636 637 638
  g_output_stream_clear_pending (stream);
  
  if (g_async_result_legacy_propagate_error (res, &error))
    nwrote = -1;
  else
639
    {
640 641
      class = G_OUTPUT_STREAM_GET_CLASS (stream);
      nwrote = class->write_finish (stream, res, &error);
642 643
    }

644 645 646 647 648
  if (nwrote >= 0)
    g_task_return_int (task, nwrote);
  else
    g_task_return_error (task, error);
  g_object_unref (task);
649 650 651 652 653
}

/**
 * g_output_stream_write_async:
 * @stream: A #GOutputStream.
654
 * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write. 
655
 * @count: the number of bytes to write
656
 * @io_priority: the io priority of the request.
657 658 659
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 * @callback: (scope async): callback to call when the request is satisfied
 * @user_data: (closure): the data to pass to callback function
660
 *
661
 * Request an asynchronous write of @count bytes from @buffer into 
662 663 664
 * the stream. When the operation is finished @callback will be called.
 * You can then call g_output_stream_write_finish() to get the result of the 
 * operation.
665
 *
666 667
 * During an async request no other sync and async calls are allowed, 
 * and will result in %G_IO_ERROR_PENDING errors. 
668
 *
669 670
 * A value of @count larger than %G_MAXSSIZE will cause a 
 * %G_IO_ERROR_INVALID_ARGUMENT error.
671 672
 *
 * On success, the number of bytes written will be passed to the
673 674 675
 * @callback. It is not an error if this is not the same as the 
 * requested size, as it can happen e.g. on a partial I/O error, 
 * but generally we try to write as many bytes as requested. 
676
 *
677 678 679 680
 * You are guaranteed that this method will never fail with
 * %G_IO_ERROR_WOULD_BLOCK - if @stream can't accept more data, the
 * method will just wait until this changes.
 *
681 682 683
 * Any outstanding I/O request with higher priority (lower numerical 
 * value) will be executed before an outstanding request with lower 
 * priority. Default priority is %G_PRIORITY_DEFAULT.
684
 *
685 686 687
 * The asyncronous methods have a default fallback that uses threads 
 * to implement asynchronicity, so they are optional for inheriting 
 * classes. However, if you override one you must override all.
688
 *
689 690
 * For the synchronous, blocking version of this function, see 
 * g_output_stream_write().
691 692 693 694 695 696 697 698 699 700 701
 **/
void
g_output_stream_write_async (GOutputStream       *stream,
			     const void          *buffer,
			     gsize                count,
			     int                  io_priority,
			     GCancellable        *cancellable,
			     GAsyncReadyCallback  callback,
			     gpointer             user_data)
{
  GOutputStreamClass *class;
702
  GError *error = NULL;
703
  GTask *task;
704 705 706 707

  g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
  g_return_if_fail (buffer != NULL);

708 709 710 711
  task = g_task_new (stream, cancellable, callback, user_data);
  g_task_set_source_tag (task, g_output_stream_write_async);
  g_task_set_priority (task, io_priority);

712 713
  if (count == 0)
    {
714 715
      g_task_return_int (task, 0);
      g_object_unref (task);
716 717 718 719 720
      return;
    }

  if (((gssize) count) < 0)
    {
721 722 723 724
      g_task_return_new_error (task, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
                               _("Too large count value passed to %s"),
                               G_STRFUNC);
      g_object_unref (task);
725 726 727
      return;
    }

728
  if (!g_output_stream_set_pending (stream, &error))
729
    {
730 731
      g_task_return_error (task, error);
      g_object_unref (task);
732 733 734 735 736 737
      return;
    }
  
  class = G_OUTPUT_STREAM_GET_CLASS (stream);

  class->write_async (stream, buffer, count, io_priority, cancellable,
738
                      async_ready_write_callback_wrapper, task);
739 740 741 742 743 744
}

/**
 * g_output_stream_write_finish:
 * @stream: a #GOutputStream.
 * @result: a #GAsyncResult.
Matthias Clasen's avatar
Matthias Clasen committed
745
 * @error: a #GError location to store the error occurring, or %NULL to 
746 747
 * ignore.
 * 
748
 * Finishes a stream write operation.
749
 * 
750
 * Returns: a #gssize containing the number of bytes written to the stream.
751 752
 **/
gssize
753 754 755
g_output_stream_write_finish (GOutputStream  *stream,
                              GAsyncResult   *result,
                              GError        **error)
756
{
757 758 759
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
  g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
  g_return_val_if_fail (g_async_result_is_tagged (result, g_output_stream_write_async), FALSE);
760

761 762 763 764
  /* @result is always the GTask created by g_output_stream_write_async();
   * we called class->write_finish() from async_ready_write_callback_wrapper.
   */
  return g_task_propagate_int (G_TASK (result), error);
765 766
}

767 768
static void
write_bytes_callback (GObject      *stream,
769 770
                      GAsyncResult *result,
                      gpointer      user_data)
771
{
772
  GTask *task = user_data;
773 774 775 776
  GError *error = NULL;
  gssize nwrote;

  nwrote = g_output_stream_write_finish (G_OUTPUT_STREAM (stream),
777
                                         result, &error);
778
  if (nwrote == -1)
779
    g_task_return_error (task, error);
780
  else
781 782
    g_task_return_int (task, nwrote);
  g_object_unref (task);
783 784 785 786 787 788 789 790 791 792 793
}

/**
 * g_output_stream_write_bytes_async:
 * @stream: A #GOutputStream.
 * @bytes: The bytes to write
 * @io_priority: the io priority of the request.
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 * @callback: (scope async): callback to call when the request is satisfied
 * @user_data: (closure): the data to pass to callback function
 *
794 795 796 797 798 799 800 801 802 803 804
 * This function is similar to g_output_stream_write_async(), but
 * takes a #GBytes as input.  Due to the refcounted nature of #GBytes,
 * this allows the stream to avoid taking a copy of the data.
 *
 * However, note that this function <emphasis>may</emphasis> still
 * perform partial writes, just like g_output_stream_write_async().
 * If that occurs, to continue writing, you will need to create a new
 * #GBytes containing just the remaining bytes, using
 * g_bytes_new_from_bytes().  Passing the same #GBytes instance
 * multiple times potentially can result in duplicated data in the
 * output stream.
805 806 807 808 809 810 811 812 813 814 815 816
 *
 * For the synchronous, blocking version of this function, see
 * g_output_stream_write_bytes().
 **/
void
g_output_stream_write_bytes_async (GOutputStream       *stream,
				   GBytes              *bytes,
				   int                  io_priority,
				   GCancellable        *cancellable,
				   GAsyncReadyCallback  callback,
				   gpointer             user_data)
{
817
  GTask *task;
818 819 820 821 822
  gsize size;
  gconstpointer data;

  data = g_bytes_get_data (bytes, &size);

823 824 825
  task = g_task_new (stream, cancellable, callback, user_data);
  g_task_set_task_data (task, g_bytes_ref (bytes),
                        (GDestroyNotify) g_bytes_unref);
826 827 828 829 830 831

  g_output_stream_write_async (stream,
                               data, size,
                               io_priority,
                               cancellable,
                               write_bytes_callback,
832
                               task);
833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851
}

/**
 * g_output_stream_write_bytes_finish:
 * @stream: a #GOutputStream.
 * @result: a #GAsyncResult.
 * @error: a #GError location to store the error occurring, or %NULL to
 * ignore.
 *
 * Finishes a stream write-from-#GBytes operation.
 *
 * Returns: a #gssize containing the number of bytes written to the stream.
 **/
gssize
g_output_stream_write_bytes_finish (GOutputStream  *stream,
				    GAsyncResult   *result,
				    GError        **error)
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
852
  g_return_val_if_fail (g_task_is_valid (result, stream), -1);
853

854
  return g_task_propagate_int (G_TASK (result), error);
855 856
}

857
static void
858 859 860
async_ready_splice_callback_wrapper (GObject      *source_object,
                                     GAsyncResult *res,
                                     gpointer     _data)
861 862
{
  GOutputStream *stream = G_OUTPUT_STREAM (source_object);
863 864 865 866 867
  GOutputStreamClass *class;
  GTask *task = _data;
  gssize nspliced;
  GError *error = NULL;

868
  g_output_stream_clear_pending (stream);
869
  
870 871 872 873 874 875 876 877 878 879 880 881 882
  if (g_async_result_legacy_propagate_error (res, &error))
    nspliced = -1;
  else
    {
      class = G_OUTPUT_STREAM_GET_CLASS (stream);
      nspliced = class->splice_finish (stream, res, &error);
    }

  if (nspliced >= 0)
    g_task_return_int (task, nspliced);
  else
    g_task_return_error (task, error);
  g_object_unref (task);
883 884 885 886
}

/**
 * g_output_stream_splice_async:
887 888 889
 * @stream: a #GOutputStream.
 * @source: a #GInputStream. 
 * @flags: a set of #GOutputStreamSpliceFlags.
890
 * @io_priority: the io priority of the request.
891 892 893
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. 
 * @callback: (scope async): a #GAsyncReadyCallback. 
 * @user_data: (closure): user data passed to @callback.
894 895
 * 
 * Splices a stream asynchronously.
896 897 898 899 900 901
 * When the operation is finished @callback will be called.
 * You can then call g_output_stream_splice_finish() to get the 
 * result of the operation.
 *
 * For the synchronous, blocking version of this function, see 
 * g_output_stream_splice().
902 903
 **/
void
904 905 906 907 908 909 910
g_output_stream_splice_async (GOutputStream            *stream,
			      GInputStream             *source,
			      GOutputStreamSpliceFlags  flags,
			      int                       io_priority,
			      GCancellable             *cancellable,
			      GAsyncReadyCallback       callback,
			      gpointer                  user_data)
911 912
{
  GOutputStreamClass *class;
913
  GTask *task;
914
  GError *error = NULL;
915 916 917 918

  g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
  g_return_if_fail (G_IS_INPUT_STREAM (source));

919 920 921 922 923
  task = g_task_new (stream, cancellable, callback, user_data);
  g_task_set_source_tag (task, g_output_stream_splice_async);
  g_task_set_priority (task, io_priority);
  g_task_set_task_data (task, g_object_ref (source), g_object_unref);

924 925
  if (g_input_stream_is_closed (source))
    {
926 927 928 929
      g_task_return_new_error (task,
                               G_IO_ERROR, G_IO_ERROR_CLOSED,
                               _("Source stream is already closed"));
      g_object_unref (task);
930 931 932
      return;
    }
  
933
  if (!g_output_stream_set_pending (stream, &error))
934
    {
935 936
      g_task_return_error (task, error);
      g_object_unref (task);
937 938 939 940 941 942
      return;
    }

  class = G_OUTPUT_STREAM_GET_CLASS (stream);

  class->splice_async (stream, source, flags, io_priority, cancellable,
943
                       async_ready_splice_callback_wrapper, task);
944 945 946 947 948 949
}

/**
 * g_output_stream_splice_finish:
 * @stream: a #GOutputStream.
 * @result: a #GAsyncResult.
Matthias Clasen's avatar
Matthias Clasen committed
950
 * @error: a #GError location to store the error occurring, or %NULL to 
951 952
 * ignore.
 *
953 954
 * Finishes an asynchronous stream splice operation.
 * 
955 956 957 958
 * Returns: a #gssize of the number of bytes spliced. Note that if the
 *     number of bytes spliced is greater than %G_MAXSSIZE, then that
 *     will be returned, and there is no way to determine the actual
 *     number of bytes spliced.
959 960
 **/
gssize
961 962 963
g_output_stream_splice_finish (GOutputStream  *stream,
			       GAsyncResult   *result,
			       GError        **error)
964
{
965 966 967
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
  g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
  g_return_val_if_fail (g_async_result_is_tagged (result, g_output_stream_splice_async), FALSE);
968

969 970 971 972 973
  /* @result is always the GTask created by g_output_stream_splice_async();
   * we called class->splice_finish() from async_ready_splice_callback_wrapper.
   */
  return g_task_propagate_int (G_TASK (result), error);
}
974

975 976 977 978 979 980 981 982 983 984 985 986
static void
async_ready_flush_callback_wrapper (GObject      *source_object,
                                    GAsyncResult *res,
                                    gpointer      user_data)
{
  GOutputStream *stream = G_OUTPUT_STREAM (source_object);
  GOutputStreamClass *class;
  GTask *task = user_data;
  gboolean flushed;
  GError *error = NULL;

  g_output_stream_clear_pending (stream);
987
  
988 989 990 991 992 993 994 995 996 997 998 999 1000
  if (g_async_result_legacy_propagate_error (res, &error))
    flushed = FALSE;
  else
    {
      class = G_OUTPUT_STREAM_GET_CLASS (stream);
      flushed = class->flush_finish (stream, res, &error);
    }

  if (flushed)
    g_task_return_boolean (task, TRUE);
  else
    g_task_return_error (task, error);
  g_object_unref (task);
1001 1002 1003 1004
}

/**
 * g_output_stream_flush_async:
1005
 * @stream: a #GOutputStream.
1006
 * @io_priority: the io priority of the request.
1007 1008 1009
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 * @callback: (scope async): a #GAsyncReadyCallback to call when the request is satisfied
 * @user_data: (closure): the data to pass to callback function
1010
 * 
1011 1012
 * Forces an asynchronous write of all user-space buffered data for
 * the given @stream.
1013 1014 1015 1016 1017
 * For behaviour details see g_output_stream_flush().
 *
 * When the operation is finished @callback will be 
 * called. You can then call g_output_stream_flush_finish() to get the 
 * result of the operation.
1018 1019 1020
 **/
void
g_output_stream_flush_async (GOutputStream       *stream,
1021 1022 1023 1024
                             int                  io_priority,
                             GCancellable        *cancellable,
                             GAsyncReadyCallback  callback,
                             gpointer             user_data)
1025 1026
{
  GOutputStreamClass *class;
1027
  GTask *task;
1028
  GError *error = NULL;
1029 1030 1031

  g_return_if_fail (G_IS_OUTPUT_STREAM (stream));

1032 1033 1034 1035
  task = g_task_new (stream, cancellable, callback, user_data);
  g_task_set_source_tag (task, g_output_stream_flush_async);
  g_task_set_priority (task, io_priority);

1036
  if (!g_output_stream_set_pending (stream, &error))
1037
    {
1038 1039
      g_task_return_error (task, error);
      g_object_unref (task);
1040 1041 1042 1043 1044 1045 1046
      return;
    }

  class = G_OUTPUT_STREAM_GET_CLASS (stream);
  
  if (class->flush_async == NULL)
    {
1047 1048
      g_task_return_boolean (task, TRUE);
      g_object_unref (task);
1049 1050 1051 1052
      return;
    }
      
  class->flush_async (stream, io_priority, cancellable,
1053
                      async_ready_flush_callback_wrapper, task);
1054 1055 1056 1057 1058 1059
}

/**
 * g_output_stream_flush_finish:
 * @stream: a #GOutputStream.
 * @result: a GAsyncResult.
Matthias Clasen's avatar
Matthias Clasen committed
1060
 * @error: a #GError location to store the error occurring, or %NULL to 
1061
 * ignore.
1062 1063 1064
 * 
 * Finishes flushing an output stream.
 * 
Matthias Clasen's avatar
Matthias Clasen committed
1065
 * Returns: %TRUE if flush operation succeeded, %FALSE otherwise.
1066 1067
 **/
gboolean
1068 1069 1070
g_output_stream_flush_finish (GOutputStream  *stream,
                              GAsyncResult   *result,
                              GError        **error)
1071 1072
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1073 1074
  g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
  g_return_val_if_fail (g_async_result_is_tagged (result, g_output_stream_flush_async), FALSE);
1075

1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096
  /* @result is always the GTask created by g_output_stream_flush_async();
   * we called class->flush_finish() from async_ready_flush_callback_wrapper.
   */
  return g_task_propagate_boolean (G_TASK (result), error);
}


static void
async_ready_close_callback_wrapper (GObject      *source_object,
                                    GAsyncResult *res,
                                    gpointer      user_data)
{
  GOutputStream *stream = G_OUTPUT_STREAM (source_object);
  GOutputStreamClass *class;
  GTask *task = user_data;
  GError *error = g_task_get_task_data (task);

  stream->priv->closing = FALSE;
  stream->priv->closed = TRUE;

  if (!error && !g_async_result_legacy_propagate_error (res, &error))
1097
    {
1098 1099 1100 1101
      class = G_OUTPUT_STREAM_GET_CLASS (stream);

      class->close_finish (stream, res,
                           error ? NULL : &error);
1102 1103
    }

1104 1105 1106 1107 1108
  if (error != NULL)
    g_task_return_error (task, error);
  else
    g_task_return_boolean (task, TRUE);
  g_object_unref (task);
1109 1110
}

1111 1112 1113 1114 1115 1116 1117 1118 1119 1120
static void
async_ready_close_flushed_callback_wrapper (GObject      *source_object,
                                            GAsyncResult *res,
                                            gpointer      user_data)
{
  GOutputStream *stream = G_OUTPUT_STREAM (source_object);
  GOutputStreamClass *class;
  GTask *task = user_data;
  GError *error = NULL;

1121 1122
  class = G_OUTPUT_STREAM_GET_CLASS (stream);

1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137
  if (!g_async_result_legacy_propagate_error (res, &error))
    {
      class->flush_finish (stream, res, &error);
    }

  /* propagate the possible error */
  if (error)
    g_task_set_task_data (task, error, NULL);

  /* we still close, even if there was a flush error */
  class->close_async (stream,
                      g_task_get_priority (task),
                      g_task_get_cancellable (task),
                      async_ready_close_callback_wrapper, task);
}
1138

1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160
static void
real_close_async_cb (GObject      *source_object,
                     GAsyncResult *res,
                     gpointer      user_data)
{
  GOutputStream *stream = G_OUTPUT_STREAM (source_object);
  GTask *task = user_data;
  GError *error = NULL;
  gboolean ret;

  g_output_stream_clear_pending (stream);

  ret = g_output_stream_internal_close_finish (stream, res, &error);

  if (error != NULL)
    g_task_return_error (task, error);
  else
    g_task_return_boolean (task, ret);

  g_object_unref (task);
}

1161 1162 1163
/**
 * g_output_stream_close_async:
 * @stream: A #GOutputStream.
Matthias Clasen's avatar
Matthias Clasen committed
1164
 * @io_priority: the io priority of the request.
1165 1166 1167
 * @cancellable: (allow-none): optional cancellable object
 * @callback: (scope async): callback to call when the request is satisfied
 * @user_data: (closure): the data to pass to callback function
1168
 *
1169 1170
 * Requests an asynchronous close of the stream, releasing resources 
 * related to it. When the operation is finished @callback will be 
1171 1172
 * called. You can then call g_output_stream_close_finish() to get 
 * the result of the operation.
1173 1174 1175
 *
 * For behaviour details see g_output_stream_close().
 *
1176 1177 1178
 * The asyncronous methods have a default fallback that uses threads 
 * to implement asynchronicity, so they are optional for inheriting 
 * classes. However, if you override one you must override all.
1179 1180
 **/
void
1181 1182 1183 1184 1185
g_output_stream_close_async (GOutputStream       *stream,
                             int                  io_priority,
                             GCancellable        *cancellable,
                             GAsyncReadyCallback  callback,
                             gpointer             user_data)
1186
{
1187
  GTask *task;
1188
  GError *error = NULL;
1189 1190 1191

  g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
  
1192 1193 1194 1195
  task = g_task_new (stream, cancellable, callback, user_data);
  g_task_set_source_tag (task, g_output_stream_close_async);
  g_task_set_priority (task, io_priority);

1196
  if (!g_output_stream_set_pending (stream, &error))
1197
    {
1198
      g_task_return_error (task, error);
1199
      g_object_unref (task);
1200 1201 1202
      return;
    }

1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224
  g_output_stream_internal_close_async (stream, io_priority, cancellable,
                                        real_close_async_cb, task);
}

/* Must always be called inside
 * g_output_stream_set_pending()/g_output_stream_clear_pending().
 */
void
g_output_stream_internal_close_async (GOutputStream       *stream,
                                      int                  io_priority,
                                      GCancellable        *cancellable,
                                      GAsyncReadyCallback  callback,
                                      gpointer             user_data)
{
  GOutputStreamClass *class;
  GTask *task;

  task = g_task_new (stream, cancellable, callback, user_data);
  g_task_set_source_tag (task, g_output_stream_internal_close_async);
  g_task_set_priority (task, io_priority);

  if (stream->priv->closed)
1225
    {
1226
      g_task_return_boolean (task, TRUE);
1227
      g_object_unref (task);
1228 1229
      return;
    }
1230

1231
  class = G_OUTPUT_STREAM_GET_CLASS (stream);
1232
  stream->priv->closing = TRUE;
1233 1234 1235 1236 1237 1238 1239 1240

  /* Call close_async directly if there is no need to flush, or if the flush
     can be done sync (in the output stream async close thread) */
  if (class->flush_async == NULL ||
      (class->flush_async == g_output_stream_real_flush_async &&
       (class->flush == NULL || class->close_async == g_output_stream_real_close_async)))
    {
      class->close_async (stream, io_priority, cancellable,
1241
                          async_ready_close_callback_wrapper, task);
1242 1243 1244 1245 1246 1247
    }
  else
    {
      /* First do an async flush, then do the async close in the callback
         wrapper (see async_ready_close_flushed_callback_wrapper) */
      class->flush_async (stream, io_priority, cancellable,
1248
                          async_ready_close_flushed_callback_wrapper, task);
1249
    }
1250 1251
}

1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
static gboolean
g_output_stream_internal_close_finish (GOutputStream  *stream,
                                       GAsyncResult   *result,
                                       GError        **error)
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
  g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
  g_return_val_if_fail (g_async_result_is_tagged (result, g_output_stream_internal_close_async), FALSE);

  return g_task_propagate_boolean (G_TASK (result), error);
}

1264 1265
/**
 * g_output_stream_close_finish:
1266 1267
 * @stream: a #GOutputStream.
 * @result: a #GAsyncResult.
Matthias Clasen's avatar
Matthias Clasen committed
1268
 * @error: a #GError location to store the error occurring, or %NULL to 
1269
 * ignore.
1270 1271 1272 1273
 * 
 * Closes an output stream.
 * 
 * Returns: %TRUE if stream was successfully closed, %FALSE otherwise.
1274 1275
 **/
gboolean
1276 1277 1278
g_output_stream_close_finish (GOutputStream  *stream,
                              GAsyncResult   *result,
                              GError        **error)
1279 1280
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1281 1282
  g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
  g_return_val_if_fail (g_async_result_is_tagged (result, g_output_stream_close_async), FALSE);
1283

1284 1285 1286 1287
  /* @result is always the GTask created by g_output_stream_close_async();
   * we called class->close_finish() from async_ready_close_callback_wrapper.
   */
  return g_task_propagate_boolean (G_TASK (result), error);
1288 1289 1290 1291
}

/**
 * g_output_stream_is_closed:
1292 1293 1294
 * @stream: a #GOutputStream.
 * 
 * Checks if an output stream has already been closed.
1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305
 * 
 * Returns: %TRUE if @stream is closed. %FALSE otherwise. 
 **/
gboolean
g_output_stream_is_closed (GOutputStream *stream)
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
  
  return stream->priv->closed;
}

1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326
/**
 * g_output_stream_is_closing:
 * @stream: a #GOutputStream.
 *
 * Checks if an output stream is being closed. This can be
 * used inside e.g. a flush implementation to see if the
 * flush (or other i/o operation) is called from within
 * the closing operation.
 *
 * Returns: %TRUE if @stream is being closed. %FALSE otherwise.
 *
 * Since: 2.24
 **/
gboolean
g_output_stream_is_closing (GOutputStream *stream)
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);

  return stream->priv->closing;
}

1327 1328
/**
 * g_output_stream_has_pending:
1329 1330 1331
 * @stream: a #GOutputStream.
 * 
 * Checks if an ouput stream has pending actions.
1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344
 * 
 * Returns: %TRUE if @stream has pending actions. 
 **/
gboolean
g_output_stream_has_pending (GOutputStream *stream)
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
  
  return stream->priv->pending;
}

/**
 * g_output_stream_set_pending:
1345
 * @stream: a #GOutputStream.
Matthias Clasen's avatar
Matthias Clasen committed
1346
 * @error: a #GError location to store the error occurring, or %NULL to 
1347
 * ignore.
1348
 * 
1349 1350 1351 1352 1353
 * Sets @stream to have actions pending. If the pending flag is
 * already set or @stream is closed, it will return %FALSE and set
 * @error.
 *
 * Return value: %TRUE if pending was previously unset and is now set.
1354
 **/
1355
gboolean
1356
g_output_stream_set_pending (GOutputStream *stream,
1357 1358 1359 1360 1361 1362
			     GError **error)
{
  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
  
  if (stream->priv->closed)
    {
1363 1364
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
                           _("Stream is already closed"));
1365 1366 1367 1368 1369
      return FALSE;
    }
  
  if (stream->priv->pending)
    {
1370 1371 1372 1373 1374
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PENDING,
                           /* Translators: This is an error you get if there is
                            * already an operation running against this stream when
                            * you try to start one */
                           _("Stream has outstanding operation"));
1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389
      return FALSE;
    }
  
  stream->priv->pending = TRUE;
  return TRUE;
}

/**
 * g_output_stream_clear_pending:
 * @stream: output stream
 * 
 * Clears the pending flag on @stream.
 **/
void
g_output_stream_clear_pending (GOutputStream *stream)
1390 1391 1392
{
  g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
  
1393
  stream->priv->pending = FALSE;
1394 1395
}

1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417
/**
 * g_output_stream_async_write_is_via_threads:
 * @stream: a #GOutputStream.
 *
 * Checks if an ouput stream's write_async function uses threads.
 *
 * Returns: %TRUE if @stream's write_async function uses threads.
 **/
gboolean
g_output_stream_async_write_is_via_threads (GOutputStream *stream)
{
  GOutputStreamClass *class;

  g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);

  class = G_OUTPUT_STREAM_GET_CLASS (stream);

  return (class->write_async == g_output_stream_real_write_async &&
      !(G_IS_POLLABLE_OUTPUT_STREAM (stream) &&
        g_pollable_output_stream_can_poll (G_POLLABLE_OUTPUT_STREAM (stream))));
}

1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428

/********************************************
 *   Default implementation of async ops    *
 ********************************************/

typedef struct {
  const void         *buffer;
  gsize               count_requested;
  gssize              count_written;
} WriteData;

1429 1430 1431 1432 1433 1434
static void
free_write_data (WriteData *op)
{
  g_slice_free (WriteData, op);
}

1435
static void
1436 1437 1438 1439
write_async_thread (GTask        *task,
                    gpointer      source_object,
                    gpointer      task_data,
                    GCancellable *cancellable)
1440
{
1441 1442
  GOutputStream *stream = source_object;
  WriteData *op = task_data;
1443 1444
  GOutputStreamClass *class;
  GError *error = NULL;
1445
  gssize count_written;
1446

1447 1448 1449 1450 1451 1452 1453
  class = G_OUTPUT_STREAM_GET_CLASS (stream);
  count_written = class->write_fn (stream, op->buffer, op->count_requested,
                                   cancellable, &error);
  if (count_written == -1)
    g_task_return_error (task, error);
  else
    g_task_return_int (task, count_written);
1454 1455
}

1456
static void write_async_pollable (GPollableOutputStream *stream,
1457
                                  GTask                 *task);
1458 1459 1460 1461 1462

static gboolean
write_async_pollable_ready (GPollableOutputStream *stream,
			    gpointer               user_data)
{
1463
  GTask *task = user_data;
1464

1465
  write_async_pollable (stream, task);
1466 1467 1468 1469 1470
  return FALSE;
}

static void
write_async_pollable (GPollableOutputStream *stream,
1471
                      GTask                 *task)
1472 1473
{
  GError *error = NULL;
1474 1475
  WriteData *op = g_task_get_task_data (task);
  gssize count_written;
1476

1477 1478 1479 1480 1481
  if (g_task_return_error_if_cancelled (task))
    return;

  count_written = G_POLLABLE_OUTPUT_STREAM_GET_INTERFACE (stream)->
    write_nonblocking (stream, op->buffer, op->count_requested, &error);
1482 1483 1484 1485 1486 1487

  if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
    {
      GSource *source;

      g_error_free (error);
1488 1489 1490 1491 1492

      source = g_pollable_output_stream_create_source (stream,
                                                       g_task_get_cancellable (task));
      g_task_attach_source (task, source,
                            (GSourceFunc) write_async_pollable_ready);
1493 1494 1495 1496
      g_source_unref (source);
      return;
    }

1497 1498
  if (count_written == -1)
    g_task_return_error (task, error);
1499
  else
1500
    g_task_return_int (task, count_written);
1501 1502
}

1503 1504
static void
g_output_stream_real_write_async (GOutputStream       *stream,
1505 1506 1507 1508 1509 1510
                                  const void          *buffer,
                                  gsize                count,
                                  int                  io_priority,
                                  GCancellable        *cancellable,
                                  GAsyncReadyCallback  callback,
                                  gpointer             user_data)
1511
{
1512
  GTask *task;
1513 1514
  WriteData *op;

1515
  op = g_slice_new0 (WriteData);
1516 1517 1518
  task = g_task_new (stream, cancellable, callback, user_data);
  g_task_set_check_cancellable (task, FALSE);
  g_task_set_task_data (task, op, (GDestroyNotify) free_write_data);
1519 1520
  op->buffer = buffer;
  op->count_requested = count;
1521

1522
  if (!g_output_stream_async_write_is_via_threads (stream))
1523
    write_async_pollable (G_POLLABLE_OUTPUT_STREAM (stream), task);
1524
  else
1525 1526
    g_task_run_in_thread (task, write_async_thread);
  g_object_unref (task);
1527 1528 1529
}

static gssize
1530 1531 1532
g_output_stream_real_write_finish (GOutputStream  *stream,
                                   GAsyncResult   *result,
                                   GError        **error)
1533
{
1534
  g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
1535

1536
  return g_task_propagate_int (G_TASK (result), error);
1537 1538 1539 1540 1541
}

typedef struct {
  GInputStream *source;
  GOutputStreamSpliceFlags flags;
1542 1543 1544 1545 1546
  gssize n_read;
  gssize n_written;
  gsize bytes_copied;
  GError *error;
  guint8 *buffer;
1547 1548 1549
} SpliceData;

static void
1550
free_splice_data (SpliceData *op)
1551
{
1552
  g_clear_pointer (&op->buffer, g_free);
1553
  g_object_unref (op->source);
1554
  g_clear_error (&op->error);
1555 1556 1557
  g_free (op);
}

1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685