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 #include "gpollableoutputstream.h"
  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  * Virtual: write_fn
 181  *
 182  * Return value: Number of bytes written, or -1 on error
 183  **/
 184 gssize
 185 g_output_stream_write (GOutputStream  *stream,
 186                        const void     *buffer,
 187                        gsize           count,
 188                        GCancellable   *cancellable,
 189                        GError        **error)
 190 {
 191   GOutputStreamClass *class;
 192   gssize res;
 193
 194   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 195   g_return_val_if_fail (buffer != NULL, 0);
 196
 197   if (count == 0)
 198     return 0;
 199
 200   if (((gssize) count) < 0)
 201     {
 202       g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 203                    _("Too large count value passed to %s"), G_STRFUNC);
 204       return -1;
 205     }
 206
 207   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 208
 209   if (class->write_fn == NULL)
 210     {
 211       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 212                            _("Output stream doesn't implement write"));
 213       return -1;
 214     }
 215
 216   if (!g_output_stream_set_pending (stream, error))
 217     return -1;
 218
 219   if (cancellable)
 220     g_cancellable_push_current (cancellable);
 221
 222   res = class->write_fn (stream, buffer, count, cancellable, error);
 223
 224   if (cancellable)
 225     g_cancellable_pop_current (cancellable);
 226
 227   g_output_stream_clear_pending (stream);
 228
 229   return res;
 230 }
 231
 232 /**
 233  * g_output_stream_write_all:
 234  * @stream: a #GOutputStream.
 235  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 236  * @count: the number of bytes to write
 237  * @bytes_written: (out): location to store the number of bytes that was
 238  *     written to the stream
 239  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 240  * @error: location to store the error occurring, or %NULL to ignore
 241  *
 242  * Tries to write @count bytes from @buffer into the stream. Will block
 243  * during the operation.
 244  *
 245  * This function is similar to g_output_stream_write(), except it tries to
 246  * write as many bytes as requested, only stopping on an error.
 247  *
 248  * On a successful write of @count bytes, %TRUE is returned, and @bytes_written
 249  * is set to @count.
 250  *
 251  * If there is an error during the operation %FALSE is returned and @error
 252  * is set to indicate the error status, @bytes_written is updated to contain
 253  * the number of bytes written into the stream before the error occurred.
 254  *
 255  * Return value: %TRUE on success, %FALSE if there was an error
 256  **/
 257 gboolean
 258 g_output_stream_write_all (GOutputStream  *stream,
 259                            const void     *buffer,
 260                            gsize           count,
 261                            gsize          *bytes_written,
 262                            GCancellable   *cancellable,
 263                            GError        **error)
 264 {
 265   gsize _bytes_written;
 266   gssize res;
 267
 268   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 269   g_return_val_if_fail (buffer != NULL, FALSE);
 270
 271   _bytes_written = 0;
 272   while (_bytes_written < count)
 273     {
 274       res = g_output_stream_write (stream, (char *)buffer + _bytes_written, count - _bytes_written,
 275                                    cancellable, error);
 276       if (res == -1)
 277         {
 278           if (bytes_written)
 279             *bytes_written = _bytes_written;
 280           return FALSE;
 281         }
 282
 283       if (res == 0)
 284         g_warning ("Write returned zero without error");
 285
 286       _bytes_written += res;
 287     }
 288
 289   if (bytes_written)
 290     *bytes_written = _bytes_written;
 291
 292   return TRUE;
 293 }
 294
 295 /**
 296  * g_output_stream_write_bytes:
 297  * @stream: a #GOutputStream.
 298  * @bytes: the #GBytes to write
 299  * @cancellable: (allow-none): optional cancellable object
 300  * @error: location to store the error occurring, or %NULL to ignore
 301  *
 302  * Tries to write the data from @bytes into the stream. Will block
 303  * during the operation.
 304  *
 305  * If @bytes is 0-length, returns 0 and does nothing. A #GBytes larger
 306  * than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
 307  *
 308  * On success, the number of bytes written to the stream is returned.
 309  * It is not an error if this is not the same as the requested size, as it
 310  * can happen e.g. on a partial I/O error, or if there is not enough
 311  * storage in the stream. All writes block until at least one byte
 312  * is written or an error occurs; 0 is never returned (unless
 313  * the size of @bytes is 0).
 314  *
 315  * If @cancellable is not %NULL, then the operation can be cancelled by
 316  * triggering the cancellable object from another thread. If the operation
 317  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an
 318  * operation was partially finished when the operation was cancelled the
 319  * partial result will be returned, without an error.
 320  *
 321  * On error -1 is returned and @error is set accordingly.
 322  *
 323  * Return value: Number of bytes written, or -1 on error
 324  **/
 325 gssize
 326 g_output_stream_write_bytes (GOutputStream  *stream,
 327                              GBytes         *bytes,
 328                              GCancellable   *cancellable,
 329                              GError        **error)
 330 {
 331   gsize size;
 332   gconstpointer data;
 333
 334   data = g_bytes_get_data (bytes, &size);
 335
 336   return g_output_stream_write (stream,
 337                                 data, size,
 338                                 cancellable,
 339                                 error);
 340 }
 341
 342 /**
 343  * g_output_stream_flush:
 344  * @stream: a #GOutputStream.
 345  * @cancellable: (allow-none): optional cancellable object
 346  * @error: location to store the error occurring, or %NULL to ignore
 347  *
 348  * Forces a write of all user-space buffered data for the given
 349  * @stream. Will block during the operation. Closing the stream will
 350  * implicitly cause a flush.
 351  *
 352  * This function is optional for inherited classes.
 353  *
 354  * If @cancellable is not %NULL, then the operation can be cancelled by
 355  * triggering the cancellable object from another thread. If the operation
 356  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 357  *
 358  * Return value: %TRUE on success, %FALSE on error
 359  **/
 360 gboolean
 361 g_output_stream_flush (GOutputStream  *stream,
 362                        GCancellable   *cancellable,
 363                        GError        **error)
 364 {
 365   GOutputStreamClass *class;
 366   gboolean res;
 367
 368   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 369
 370   if (!g_output_stream_set_pending (stream, error))
 371     return FALSE;
 372
 373   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 374
 375   res = TRUE;
 376   if (class->flush)
 377     {
 378       if (cancellable)
 379         g_cancellable_push_current (cancellable);
 380
 381       res = class->flush (stream, cancellable, error);
 382
 383       if (cancellable)
 384         g_cancellable_pop_current (cancellable);
 385     }
 386
 387   g_output_stream_clear_pending (stream);
 388
 389   return res;
 390 }
 391
 392 /**
 393  * g_output_stream_splice:
 394  * @stream: a #GOutputStream.
 395  * @source: a #GInputStream.
 396  * @flags: a set of #GOutputStreamSpliceFlags.
 397  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 398  * @error: a #GError location to store the error occurring, or %NULL to
 399  * ignore.
 400  *
 401  * Splices an input stream into an output stream.
 402  *
 403  * Returns: a #gssize containing the size of the data spliced, or
 404  *     -1 if an error occurred. Note that if the number of bytes
 405  *     spliced is greater than %G_MAXSSIZE, then that will be
 406  *     returned, and there is no way to determine the actual number
 407  *     of bytes spliced.
 408  **/
 409 gssize
 410 g_output_stream_splice (GOutputStream             *stream,
 411                         GInputStream              *source,
 412                         GOutputStreamSpliceFlags   flags,
 413                         GCancellable              *cancellable,
 414                         GError                   **error)
 415 {
 416   GOutputStreamClass *class;
 417   gssize bytes_copied;
 418
 419   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 420   g_return_val_if_fail (G_IS_INPUT_STREAM (source), -1);
 421
 422   if (g_input_stream_is_closed (source))
 423     {
 424       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
 425                            _("Source stream is already closed"));
 426       return -1;
 427     }
 428
 429   if (!g_output_stream_set_pending (stream, error))
 430     return -1;
 431
 432   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 433
 434   if (cancellable)
 435     g_cancellable_push_current (cancellable);
 436
 437   bytes_copied = class->splice (stream, source, flags, cancellable, error);
 438
 439   if (cancellable)
 440     g_cancellable_pop_current (cancellable);
 441
 442   g_output_stream_clear_pending (stream);
 443
 444   return bytes_copied;
 445 }
 446
 447 static gssize
 448 g_output_stream_real_splice (GOutputStream             *stream,
 449                              GInputStream              *source,
 450                              GOutputStreamSpliceFlags   flags,
 451                              GCancellable              *cancellable,
 452                              GError                   **error)
 453 {
 454   GOutputStreamClass *class = G_OUTPUT_STREAM_GET_CLASS (stream);
 455   gssize n_read, n_written;
 456   gsize bytes_copied;
 457   char buffer[8192], *p;
 458   gboolean res;
 459
 460   bytes_copied = 0;
 461   if (class->write_fn == NULL)
 462     {
 463       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 464                            _("Output stream doesn't implement write"));
 465       res = FALSE;
 466       goto notsupported;
 467     }
 468
 469   res = TRUE;
 470   do
 471     {
 472       n_read = g_input_stream_read (source, buffer, sizeof (buffer), cancellable, error);
 473       if (n_read == -1)
 474         {
 475           res = FALSE;
 476           break;
 477         }
 478
 479       if (n_read == 0)
 480         break;
 481
 482       p = buffer;
 483       while (n_read > 0)
 484         {
 485           n_written = class->write_fn (stream, p, n_read, cancellable, error);
 486           if (n_written == -1)
 487             {
 488               res = FALSE;
 489               break;
 490             }
 491
 492           p += n_written;
 493           n_read -= n_written;
 494           bytes_copied += n_written;
 495         }
 496
 497       if (bytes_copied > G_MAXSSIZE)
 498         bytes_copied = G_MAXSSIZE;
 499     }
 500   while (res);
 501
 502  notsupported:
 503   if (!res)
 504     error = NULL; /* Ignore further errors */
 505
 506   if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_SOURCE)
 507     {
 508       /* Don't care about errors in source here */
 509       g_input_stream_close (source, cancellable, NULL);
 510     }
 511
 512   if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET)
 513     {
 514       /* But write errors on close are bad! */
 515       res = _g_output_stream_close_internal (stream, cancellable, error);
 516     }
 517
 518   if (res)
 519     return bytes_copied;
 520
 521   return -1;
 522 }
 523
 524 /* Must always be called inside
 525  * g_output_stream_set_pending()/g_output_stream_clear_pending(). */
 526 static gboolean
 527 _g_output_stream_close_internal (GOutputStream  *stream,
 528                                  GCancellable   *cancellable,
 529                                  GError        **error)
 530 {
 531   GOutputStreamClass *class;
 532   gboolean res;
 533
 534   if (stream->priv->closed)
 535     return TRUE;
 536
 537   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 538
 539   stream->priv->closing = TRUE;
 540
 541   if (cancellable)
 542     g_cancellable_push_current (cancellable);
 543
 544   if (class->flush)
 545     res = class->flush (stream, cancellable, error);
 546   else
 547     res = TRUE;
 548
 549   if (!res)
 550     {
 551       /* flushing caused the error that we want to return,
 552        * but we still want to close the underlying stream if possible
 553        */
 554       if (class->close_fn)
 555         class->close_fn (stream, cancellable, NULL);
 556     }
 557   else
 558     {
 559       res = TRUE;
 560       if (class->close_fn)
 561         res = class->close_fn (stream, cancellable, error);
 562     }
 563
 564   if (cancellable)
 565     g_cancellable_pop_current (cancellable);
 566
 567   stream->priv->closing = FALSE;
 568   stream->priv->closed = TRUE;
 569
 570   return res;
 571 }
 572
 573 /**
 574  * g_output_stream_close:
 575  * @stream: A #GOutputStream.
 576  * @cancellable: (allow-none): optional cancellable object
 577  * @error: location to store the error occurring, or %NULL to ignore
 578  *
 579  * Closes the stream, releasing resources related to it.
 580  *
 581  * Once the stream is closed, all other operations will return %G_IO_ERROR_CLOSED.
 582  * Closing a stream multiple times will not return an error.
 583  *
 584  * Closing a stream will automatically flush any outstanding buffers in the
 585  * stream.
 586  *
 587  * Streams will be automatically closed when the last reference
 588  * is dropped, but you might want to call this function to make sure
 589  * resources are released as early as possible.
 590  *
 591  * Some streams might keep the backing store of the stream (e.g. a file descriptor)
 592  * open after the stream is closed. See the documentation for the individual
 593  * stream for details.
 594  *
 595  * On failure the first error that happened will be reported, but the close
 596  * operation will finish as much as possible. A stream that failed to
 597  * close will still return %G_IO_ERROR_CLOSED for all operations. Still, it
 598  * is important to check and report the error to the user, otherwise
 599  * there might be a loss of data as all data might not be written.
 600  *
 601  * If @cancellable is not %NULL, then the operation can be cancelled by
 602  * triggering the cancellable object from another thread. If the operation
 603  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 604  * Cancelling a close will still leave the stream closed, but there some streams
 605  * can use a faster close that doesn't block to e.g. check errors. On
 606  * cancellation (as with any error) there is no guarantee that all written
 607  * data will reach the target.
 608  *
 609  * Return value: %TRUE on success, %FALSE on failure
 610  **/
 611 gboolean
 612 g_output_stream_close (GOutputStream  *stream,
 613                        GCancellable   *cancellable,
 614                        GError        **error)
 615 {
 616   gboolean res;
 617
 618   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 619
 620   if (stream->priv->closed)
 621     return TRUE;
 622
 623   if (!g_output_stream_set_pending (stream, error))
 624     return FALSE;
 625
 626   res = _g_output_stream_close_internal (stream, cancellable, error);
 627
 628   g_output_stream_clear_pending (stream);
 629
 630   return res;
 631 }
 632
 633 static void
 634 async_ready_callback_wrapper (GObject      *source_object,
 635                               GAsyncResult *res,
 636                               gpointer      user_data)
 637 {
 638   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 639
 640   g_output_stream_clear_pending (stream);
 641   if (stream->priv->outstanding_callback)
 642     (*stream->priv->outstanding_callback) (source_object, res, user_data);
 643   g_object_unref (stream);
 644 }
 645
 646 typedef struct {
 647   gint io_priority;
 648   GCancellable *cancellable;
 649   GError *flush_error;
 650   gpointer user_data;
 651 } CloseUserData;
 652
 653 static void
 654 async_ready_close_callback_wrapper (GObject      *source_object,
 655                                     GAsyncResult *res,
 656                                     gpointer      user_data)
 657 {
 658   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 659   CloseUserData *data = user_data;
 660
 661   stream->priv->closing = FALSE;
 662   stream->priv->closed = TRUE;
 663
 664   g_output_stream_clear_pending (stream);
 665
 666   if (stream->priv->outstanding_callback)
 667     {
 668       if (data->flush_error != NULL)
 669         {
 670           GSimpleAsyncResult *err;
 671
 672           err = g_simple_async_result_new_take_error (source_object,
 673                                                       stream->priv->outstanding_callback,
 674                                                       data->user_data,
 675                                                       data->flush_error);
 676           data->flush_error = NULL;
 677
 678           (*stream->priv->outstanding_callback) (source_object,
 679                                                  G_ASYNC_RESULT (err),
 680                                                  data->user_data);
 681           g_object_unref (err);
 682         }
 683       else
 684         {
 685           (*stream->priv->outstanding_callback) (source_object,
 686                                                  res,
 687                                                  data->user_data);
 688         }
 689     }
 690
 691   g_object_unref (stream);
 692
 693   if (data->cancellable)
 694     g_object_unref (data->cancellable);
 695
 696   if (data->flush_error)
 697     g_error_free (data->flush_error);
 698
 699   g_slice_free (CloseUserData, data);
 700 }
 701
 702 static void
 703 async_ready_close_flushed_callback_wrapper (GObject      *source_object,
 704                                             GAsyncResult *res,
 705                                             gpointer      user_data)
 706 {
 707   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 708   GOutputStreamClass *class;
 709   CloseUserData *data = user_data;
 710   GSimpleAsyncResult *simple;
 711
 712   /* propagate the possible error */
 713   if (G_IS_SIMPLE_ASYNC_RESULT (res))
 714     {
 715       simple = G_SIMPLE_ASYNC_RESULT (res);
 716       g_simple_async_result_propagate_error (simple, &data->flush_error);
 717     }
 718
 719   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 720
 721   /* we still close, even if there was a flush error */
 722   class->close_async (stream, data->io_priority, data->cancellable,
 723                       async_ready_close_callback_wrapper, user_data);
 724 }
 725
 726 /**
 727  * g_output_stream_write_async:
 728  * @stream: A #GOutputStream.
 729  * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write.
 730  * @count: the number of bytes to write
 731  * @io_priority: the io priority of the request.
 732  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 733  * @callback: (scope async): callback to call when the request is satisfied
 734  * @user_data: (closure): the data to pass to callback function
 735  *
 736  * Request an asynchronous write of @count bytes from @buffer into
 737  * the stream. When the operation is finished @callback will be called.
 738  * You can then call g_output_stream_write_finish() to get the result of the
 739  * operation.
 740  *
 741  * During an async request no other sync and async calls are allowed,
 742  * and will result in %G_IO_ERROR_PENDING errors.
 743  *
 744  * A value of @count larger than %G_MAXSSIZE will cause a
 745  * %G_IO_ERROR_INVALID_ARGUMENT error.
 746  *
 747  * On success, the number of bytes written will be passed to the
 748  * @callback. It is not an error if this is not the same as the
 749  * requested size, as it can happen e.g. on a partial I/O error,
 750  * but generally we try to write as many bytes as requested.
 751  *
 752  * You are guaranteed that this method will never fail with
 753  * %G_IO_ERROR_WOULD_BLOCK - if @stream can't accept more data, the
 754  * method will just wait until this changes.
 755  *
 756  * Any outstanding I/O request with higher priority (lower numerical
 757  * value) will be executed before an outstanding request with lower
 758  * priority. Default priority is %G_PRIORITY_DEFAULT.
 759  *
 760  * The asyncronous methods have a default fallback that uses threads
 761  * to implement asynchronicity, so they are optional for inheriting
 762  * classes. However, if you override one you must override all.
 763  *
 764  * For the synchronous, blocking version of this function, see
 765  * g_output_stream_write().
 766  **/
 767 void
 768 g_output_stream_write_async (GOutputStream       *stream,
 769                              const void          *buffer,
 770                              gsize                count,
 771                              int                  io_priority,
 772                              GCancellable        *cancellable,
 773                              GAsyncReadyCallback  callback,
 774                              gpointer             user_data)
 775 {
 776   GOutputStreamClass *class;
 777   GSimpleAsyncResult *simple;
 778   GError *error = NULL;
 779
 780   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 781   g_return_if_fail (buffer != NULL);
 782
 783   if (count == 0)
 784     {
 785       simple = g_simple_async_result_new (G_OBJECT (stream),
 786                                           callback,
 787                                           user_data,
 788                                           g_output_stream_write_async);
 789       g_simple_async_result_complete_in_idle (simple);
 790       g_object_unref (simple);
 791       return;
 792     }
 793
 794   if (((gssize) count) < 0)
 795     {
 796       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 797                                            callback,
 798                                            user_data,
 799                                            G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 800                                            _("Too large count value passed to %s"),
 801                                            G_STRFUNC);
 802       return;
 803     }
 804
 805   if (!g_output_stream_set_pending (stream, &error))
 806     {
 807       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
 808                                             callback,
 809                                             user_data,
 810                                             error);
 811       return;
 812     }
 813
 814   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 815
 816   stream->priv->outstanding_callback = callback;
 817   g_object_ref (stream);
 818   class->write_async (stream, buffer, count, io_priority, cancellable,
 819                       async_ready_callback_wrapper, user_data);
 820 }
 821
 822 /**
 823  * g_output_stream_write_finish:
 824  * @stream: a #GOutputStream.
 825  * @result: a #GAsyncResult.
 826  * @error: a #GError location to store the error occurring, or %NULL to
 827  * ignore.
 828  *
 829  * Finishes a stream write operation.
 830  *
 831  * Returns: a #gssize containing the number of bytes written to the stream.
 832  **/
 833 gssize
 834 g_output_stream_write_finish (GOutputStream  *stream,
 835                               GAsyncResult   *result,
 836                               GError        **error)
 837 {
 838   GSimpleAsyncResult *simple;
 839   GOutputStreamClass *class;
 840
 841   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 842   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
 843
 844   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 845     {
 846       simple = G_SIMPLE_ASYNC_RESULT (result);
 847       if (g_simple_async_result_propagate_error (simple, error))
 848         return -1;
 849
 850       /* Special case writes of 0 bytes */
 851       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_write_async)
 852         return 0;
 853     }
 854
 855   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 856   return class->write_finish (stream, result, error);
 857 }
 858
 859 static void
 860 write_bytes_callback (GObject      *stream,
 861                       GAsyncResult *result,
 862                       gpointer      user_data)
 863 {
 864   GSimpleAsyncResult *simple = user_data;
 865   GError *error = NULL;
 866   gssize nwrote;
 867
 868   nwrote = g_output_stream_write_finish (G_OUTPUT_STREAM (stream),
 869                                          result, &error);
 870   if (nwrote == -1)
 871     g_simple_async_result_take_error (simple, error);
 872   else
 873     g_simple_async_result_set_op_res_gssize (simple, nwrote);
 874   g_simple_async_result_complete (simple);
 875   g_object_unref (simple);
 876 }
 877
 878 /**
 879  * g_output_stream_write_bytes_async:
 880  * @stream: A #GOutputStream.
 881  * @bytes: The bytes to write
 882  * @io_priority: the io priority of the request.
 883  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
 884  * @callback: (scope async): callback to call when the request is satisfied
 885  * @user_data: (closure): the data to pass to callback function
 886  *
 887  * Request an asynchronous write of the data in @bytes to the stream.
 888  * When the operation is finished @callback will be called. You can
 889  * then call g_output_stream_write_bytes_finish() to get the result of
 890  * the operation.
 891  *
 892  * During an async request no other sync and async calls are allowed,
 893  * and will result in %G_IO_ERROR_PENDING errors.
 894  *
 895  * A #GBytes larger than %G_MAXSSIZE will cause a
 896  * %G_IO_ERROR_INVALID_ARGUMENT error.
 897  *
 898  * On success, the number of bytes written will be passed to the
 899  * @callback. It is not an error if this is not the same as the
 900  * requested size, as it can happen e.g. on a partial I/O error,
 901  * but generally we try to write as many bytes as requested.
 902  *
 903  * You are guaranteed that this method will never fail with
 904  * %G_IO_ERROR_WOULD_BLOCK - if @stream can't accept more data, the
 905  * method will just wait until this changes.
 906  *
 907  * Any outstanding I/O request with higher priority (lower numerical
 908  * value) will be executed before an outstanding request with lower
 909  * priority. Default priority is %G_PRIORITY_DEFAULT.
 910  *
 911  * For the synchronous, blocking version of this function, see
 912  * g_output_stream_write_bytes().
 913  **/
 914 void
 915 g_output_stream_write_bytes_async (GOutputStream       *stream,
 916                                    GBytes              *bytes,
 917                                    int                  io_priority,
 918                                    GCancellable        *cancellable,
 919                                    GAsyncReadyCallback  callback,
 920                                    gpointer             user_data)
 921 {
 922   GSimpleAsyncResult *simple;
 923   gsize size;
 924   gconstpointer data;
 925
 926   data = g_bytes_get_data (bytes, &size);
 927
 928   simple = g_simple_async_result_new (G_OBJECT (stream),
 929                                       callback, user_data,
 930                                       g_output_stream_write_bytes_async);
 931   g_simple_async_result_set_op_res_gpointer (simple, g_bytes_ref (bytes),
 932                                              (GDestroyNotify) g_bytes_unref);
 933
 934   g_output_stream_write_async (stream,
 935                                data, size,
 936                                io_priority,
 937                                cancellable,
 938                                write_bytes_callback,
 939                                simple);
 940 }
 941
 942 /**
 943  * g_output_stream_write_bytes_finish:
 944  * @stream: a #GOutputStream.
 945  * @result: a #GAsyncResult.
 946  * @error: a #GError location to store the error occurring, or %NULL to
 947  * ignore.
 948  *
 949  * Finishes a stream write-from-#GBytes operation.
 950  *
 951  * Returns: a #gssize containing the number of bytes written to the stream.
 952  **/
 953 gssize
 954 g_output_stream_write_bytes_finish (GOutputStream  *stream,
 955                                     GAsyncResult   *result,
 956                                     GError        **error)
 957 {
 958   GSimpleAsyncResult *simple;
 959
 960   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 961   g_return_val_if_fail (g_simple_async_result_is_valid (result, G_OBJECT (stream), g_output_stream_write_bytes_async), -1);
 962
 963   simple = G_SIMPLE_ASYNC_RESULT (result);
 964   if (g_simple_async_result_propagate_error (simple, error))
 965     return -1;
 966   return g_simple_async_result_get_op_res_gssize (simple);
 967 }
 968
 969 typedef struct {
 970   GInputStream *source;
 971   gpointer user_data;
 972   GAsyncReadyCallback callback;
 973 } SpliceUserData;
 974
 975 static void
 976 async_ready_splice_callback_wrapper (GObject      *source_object,
 977                                      GAsyncResult *res,
 978                                      gpointer     _data)
 979 {
 980   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 981   SpliceUserData *data = _data;
 982
 983   g_output_stream_clear_pending (stream);
 984
 985   if (data->callback)
 986     (*data->callback) (source_object, res, data->user_data);
 987
 988   g_object_unref (stream);
 989   g_object_unref (data->source);
 990   g_free (data);
 991 }
 992
 993 /**
 994  * g_output_stream_splice_async:
 995  * @stream: a #GOutputStream.
 996  * @source: a #GInputStream.
 997  * @flags: a set of #GOutputStreamSpliceFlags.
 998  * @io_priority: the io priority of the request.
 999  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
1000  * @callback: (scope async): a #GAsyncReadyCallback.
1001  * @user_data: (closure): user data passed to @callback.
1002  *
1003  * Splices a stream asynchronously.
1004  * When the operation is finished @callback will be called.
1005  * You can then call g_output_stream_splice_finish() to get the
1006  * result of the operation.
1007  *
1008  * For the synchronous, blocking version of this function, see
1009  * g_output_stream_splice().
1010  **/
1011 void
1012 g_output_stream_splice_async (GOutputStream            *stream,
1013                               GInputStream             *source,
1014                               GOutputStreamSpliceFlags  flags,
1015                               int                       io_priority,
1016                               GCancellable             *cancellable,
1017                               GAsyncReadyCallback       callback,
1018                               gpointer                  user_data)
1019 {
1020   GOutputStreamClass *class;
1021   SpliceUserData *data;
1022   GError *error = NULL;
1023
1024   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1025   g_return_if_fail (G_IS_INPUT_STREAM (source));
1026
1027   if (g_input_stream_is_closed (source))
1028     {
1029       g_simple_async_report_error_in_idle (G_OBJECT (stream),
1030                                            callback,
1031                                            user_data,
1032                                            G_IO_ERROR, G_IO_ERROR_CLOSED,
1033                                            _("Source stream is already closed"));
1034       return;
1035     }
1036
1037   if (!g_output_stream_set_pending (stream, &error))
1038     {
1039       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
1040                                             callback,
1041                                             user_data,
1042                                             error);
1043       return;
1044     }
1045
1046   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1047
1048   data = g_new0 (SpliceUserData, 1);
1049   data->callback = callback;
1050   data->user_data = user_data;
1051   data->source = g_object_ref (source);
1052
1053   g_object_ref (stream);
1054   class->splice_async (stream, source, flags, io_priority, cancellable,
1055                       async_ready_splice_callback_wrapper, data);
1056 }
1057
1058 /**
1059  * g_output_stream_splice_finish:
1060  * @stream: a #GOutputStream.
1061  * @result: a #GAsyncResult.
1062  * @error: a #GError location to store the error occurring, or %NULL to
1063  * ignore.
1064  *
1065  * Finishes an asynchronous stream splice operation.
1066  *
1067  * Returns: a #gssize of the number of bytes spliced. Note that if the
1068  *     number of bytes spliced is greater than %G_MAXSSIZE, then that
1069  *     will be returned, and there is no way to determine the actual
1070  *     number of bytes spliced.
1071  **/
1072 gssize
1073 g_output_stream_splice_finish (GOutputStream  *stream,
1074                                GAsyncResult   *result,
1075                                GError        **error)
1076 {
1077   GSimpleAsyncResult *simple;
1078   GOutputStreamClass *class;
1079
1080   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
1081   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
1082
1083   if (G_IS_SIMPLE_ASYNC_RESULT (result))
1084     {
1085       simple = G_SIMPLE_ASYNC_RESULT (result);
1086       if (g_simple_async_result_propagate_error (simple, error))
1087         return -1;
1088     }
1089
1090   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1091   return class->splice_finish (stream, result, error);
1092 }
1093
1094 /**
1095  * g_output_stream_flush_async:
1096  * @stream: a #GOutputStream.
1097  * @io_priority: the io priority of the request.
1098  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
1099  * @callback: (scope async): a #GAsyncReadyCallback to call when the request is satisfied
1100  * @user_data: (closure): the data to pass to callback function
1101  *
1102  * Forces an asynchronous write of all user-space buffered data for
1103  * the given @stream.
1104  * For behaviour details see g_output_stream_flush().
1105  *
1106  * When the operation is finished @callback will be
1107  * called. You can then call g_output_stream_flush_finish() to get the
1108  * result of the operation.
1109  **/
1110 void
1111 g_output_stream_flush_async (GOutputStream       *stream,
1112                              int                  io_priority,
1113                              GCancellable        *cancellable,
1114                              GAsyncReadyCallback  callback,
1115                              gpointer             user_data)
1116 {
1117   GOutputStreamClass *class;
1118   GSimpleAsyncResult *simple;
1119   GError *error = NULL;
1120
1121   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1122
1123   if (!g_output_stream_set_pending (stream, &error))
1124     {
1125       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
1126                                             callback,
1127                                             user_data,
1128                                             error);
1129       return;
1130     }
1131
1132   stream->priv->outstanding_callback = callback;
1133   g_object_ref (stream);
1134
1135   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1136
1137   if (class->flush_async == NULL)
1138     {
1139       simple = g_simple_async_result_new (G_OBJECT (stream),
1140                                           async_ready_callback_wrapper,
1141                                           user_data,
1142                                           g_output_stream_flush_async);
1143       g_simple_async_result_complete_in_idle (simple);
1144       g_object_unref (simple);
1145       return;
1146     }
1147
1148   class->flush_async (stream, io_priority, cancellable,
1149                       async_ready_callback_wrapper, user_data);
1150 }
1151
1152 /**
1153  * g_output_stream_flush_finish:
1154  * @stream: a #GOutputStream.
1155  * @result: a GAsyncResult.
1156  * @error: a #GError location to store the error occurring, or %NULL to
1157  * ignore.
1158  *
1159  * Finishes flushing an output stream.
1160  *
1161  * Returns: %TRUE if flush operation succeeded, %FALSE otherwise.
1162  **/
1163 gboolean
1164 g_output_stream_flush_finish (GOutputStream  *stream,
1165                               GAsyncResult   *result,
1166                               GError        **error)
1167 {
1168   GSimpleAsyncResult *simple;
1169   GOutputStreamClass *klass;
1170
1171   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1172   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
1173
1174   if (G_IS_SIMPLE_ASYNC_RESULT (result))
1175     {
1176       simple = G_SIMPLE_ASYNC_RESULT (result);
1177       if (g_simple_async_result_propagate_error (simple, error))
1178         return FALSE;
1179
1180       /* Special case default implementation */
1181       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_flush_async)
1182         return TRUE;
1183     }
1184
1185   klass = G_OUTPUT_STREAM_GET_CLASS (stream);
1186   return klass->flush_finish (stream, result, error);
1187 }
1188
1189
1190 /**
1191  * g_output_stream_close_async:
1192  * @stream: A #GOutputStream.
1193  * @io_priority: the io priority of the request.
1194  * @cancellable: (allow-none): optional cancellable object
1195  * @callback: (scope async): callback to call when the request is satisfied
1196  * @user_data: (closure): the data to pass to callback function
1197  *
1198  * Requests an asynchronous close of the stream, releasing resources
1199  * related to it. When the operation is finished @callback will be
1200  * called. You can then call g_output_stream_close_finish() to get
1201  * the result of the operation.
1202  *
1203  * For behaviour details see g_output_stream_close().
1204  *
1205  * The asyncronous methods have a default fallback that uses threads
1206  * to implement asynchronicity, so they are optional for inheriting
1207  * classes. However, if you override one you must override all.
1208  **/
1209 void
1210 g_output_stream_close_async (GOutputStream       *stream,
1211                              int                  io_priority,
1212                              GCancellable        *cancellable,
1213                              GAsyncReadyCallback  callback,
1214                              gpointer             user_data)
1215 {
1216   GOutputStreamClass *class;
1217   GSimpleAsyncResult *simple;
1218   GError *error = NULL;
1219   CloseUserData *data;
1220
1221   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1222
1223   if (stream->priv->closed)
1224     {
1225       simple = g_simple_async_result_new (G_OBJECT (stream),
1226                                           callback,
1227                                           user_data,
1228                                           g_output_stream_close_async);
1229       g_simple_async_result_complete_in_idle (simple);
1230       g_object_unref (simple);
1231       return;
1232     }
1233
1234   if (!g_output_stream_set_pending (stream, &error))
1235     {
1236       g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream),
1237                                             callback,
1238                                             user_data,
1239                                             error);
1240       return;
1241     }
1242
1243   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1244   stream->priv->closing = TRUE;
1245   stream->priv->outstanding_callback = callback;
1246   g_object_ref (stream);
1247
1248   data = g_slice_new0 (CloseUserData);
1249
1250   if (cancellable != NULL)
1251     data->cancellable = g_object_ref (cancellable);
1252
1253   data->io_priority = io_priority;
1254   data->user_data = user_data;
1255
1256   /* Call close_async directly if there is no need to flush, or if the flush
1257      can be done sync (in the output stream async close thread) */
1258   if (class->flush_async == NULL ||
1259       (class->flush_async == g_output_stream_real_flush_async &&
1260        (class->flush == NULL || class->close_async == g_output_stream_real_close_async)))
1261     {
1262       class->close_async (stream, io_priority, cancellable,
1263                           async_ready_close_callback_wrapper, data);
1264     }
1265   else
1266     {
1267       /* First do an async flush, then do the async close in the callback
1268          wrapper (see async_ready_close_flushed_callback_wrapper) */
1269       class->flush_async (stream, io_priority, cancellable,
1270                           async_ready_close_flushed_callback_wrapper, data);
1271     }
1272 }
1273
1274 /**
1275  * g_output_stream_close_finish:
1276  * @stream: a #GOutputStream.
1277  * @result: a #GAsyncResult.
1278  * @error: a #GError location to store the error occurring, or %NULL to
1279  * ignore.
1280  *
1281  * Closes an output stream.
1282  *
1283  * Returns: %TRUE if stream was successfully closed, %FALSE otherwise.
1284  **/
1285 gboolean
1286 g_output_stream_close_finish (GOutputStream  *stream,
1287                               GAsyncResult   *result,
1288                               GError        **error)
1289 {
1290   GSimpleAsyncResult *simple;
1291   GOutputStreamClass *class;
1292
1293   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1294   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
1295
1296   if (G_IS_SIMPLE_ASYNC_RESULT (result))
1297     {
1298       simple = G_SIMPLE_ASYNC_RESULT (result);
1299       if (g_simple_async_result_propagate_error (simple, error))
1300         return FALSE;
1301
1302       /* Special case already closed */
1303       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_close_async)
1304         return TRUE;
1305     }
1306
1307   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1308   return class->close_finish (stream, result, error);
1309 }
1310
1311 /**
1312  * g_output_stream_is_closed:
1313  * @stream: a #GOutputStream.
1314  *
1315  * Checks if an output stream has already been closed.
1316  *
1317  * Returns: %TRUE if @stream is closed. %FALSE otherwise.
1318  **/
1319 gboolean
1320 g_output_stream_is_closed (GOutputStream *stream)
1321 {
1322   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
1323
1324   return stream->priv->closed;
1325 }
1326
1327 /**
1328  * g_output_stream_is_closing:
1329  * @stream: a #GOutputStream.
1330  *
1331  * Checks if an output stream is being closed. This can be
1332  * used inside e.g. a flush implementation to see if the
1333  * flush (or other i/o operation) is called from within
1334  * the closing operation.
1335  *
1336  * Returns: %TRUE if @stream is being closed. %FALSE otherwise.
1337  *
1338  * Since: 2.24
1339  **/
1340 gboolean
1341 g_output_stream_is_closing (GOutputStream *stream)
1342 {
1343   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
1344
1345   return stream->priv->closing;
1346 }
1347
1348 /**
1349  * g_output_stream_has_pending:
1350  * @stream: a #GOutputStream.
1351  *
1352  * Checks if an ouput stream has pending actions.
1353  *
1354  * Returns: %TRUE if @stream has pending actions.
1355  **/
1356 gboolean
1357 g_output_stream_has_pending (GOutputStream *stream)
1358 {
1359   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1360
1361   return stream->priv->pending;
1362 }
1363
1364 /**
1365  * g_output_stream_set_pending:
1366  * @stream: a #GOutputStream.
1367  * @error: a #GError location to store the error occurring, or %NULL to
1368  * ignore.
1369  *
1370  * Sets @stream to have actions pending. If the pending flag is
1371  * already set or @stream is closed, it will return %FALSE and set
1372  * @error.
1373  *
1374  * Return value: %TRUE if pending was previously unset and is now set.
1375  **/
1376 gboolean
1377 g_output_stream_set_pending (GOutputStream *stream,
1378                              GError **error)
1379 {
1380   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1381
1382   if (stream->priv->closed)
1383     {
1384       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
1385                            _("Stream is already closed"));
1386       return FALSE;
1387     }
1388
1389   if (stream->priv->pending)
1390     {
1391       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PENDING,
1392                            /* Translators: This is an error you get if there is
1393                             * already an operation running against this stream when
1394                             * you try to start one */
1395                            _("Stream has outstanding operation"));
1396       return FALSE;
1397     }
1398
1399   stream->priv->pending = TRUE;
1400   return TRUE;
1401 }
1402
1403 /**
1404  * g_output_stream_clear_pending:
1405  * @stream: output stream
1406  *
1407  * Clears the pending flag on @stream.
1408  **/
1409 void
1410 g_output_stream_clear_pending (GOutputStream *stream)
1411 {
1412   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1413
1414   stream->priv->pending = FALSE;
1415 }
1416
1417
1418 /********************************************
1419  *   Default implementation of async ops    *
1420  ********************************************/
1421
1422 typedef struct {
1423   const void         *buffer;
1424   gsize               count_requested;
1425   gssize              count_written;
1426
1427   GCancellable       *cancellable;
1428   gint                io_priority;
1429   gboolean            need_idle;
1430 } WriteData;
1431
1432 static void
1433 free_write_data (WriteData *op)
1434 {
1435   if (op->cancellable)
1436     g_object_unref (op->cancellable);
1437   g_slice_free (WriteData, op);
1438 }
1439
1440 static void
1441 write_async_thread (GSimpleAsyncResult *res,
1442                     GObject            *object,
1443                     GCancellable       *cancellable)
1444 {
1445   WriteData *op;
1446   GOutputStreamClass *class;
1447   GError *error = NULL;
1448
1449   class = G_OUTPUT_STREAM_GET_CLASS (object);
1450   op = g_simple_async_result_get_op_res_gpointer (res);
1451   op->count_written = class->write_fn (G_OUTPUT_STREAM (object), op->buffer, op->count_requested,
1452                                        cancellable, &error);
1453   if (op->count_written == -1)
1454     g_simple_async_result_take_error (res, error);
1455 }
1456
1457 static void write_async_pollable (GPollableOutputStream *stream,
1458                                   GSimpleAsyncResult    *result);
1459
1460 static gboolean
1461 write_async_pollable_ready (GPollableOutputStream *stream,
1462                             gpointer               user_data)
1463 {
1464   GSimpleAsyncResult *result = user_data;
1465
1466   write_async_pollable (stream, result);
1467   return FALSE;
1468 }
1469
1470 static void
1471 write_async_pollable (GPollableOutputStream *stream,
1472                       GSimpleAsyncResult    *result)
1473 {
1474   GError *error = NULL;
1475   WriteData *op = g_simple_async_result_get_op_res_gpointer (result);
1476
1477   if (g_cancellable_set_error_if_cancelled (op->cancellable, &error))
1478     op->count_written = -1;
1479   else
1480     {
1481       op->count_written = G_POLLABLE_OUTPUT_STREAM_GET_INTERFACE (stream)->
1482         write_nonblocking (stream, op->buffer, op->count_requested, &error);
1483     }
1484
1485   if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
1486     {
1487       GSource *source;
1488
1489       g_error_free (error);
1490       op->need_idle = FALSE;
1491
1492       source = g_pollable_output_stream_create_source (stream, op->cancellable);
1493       g_source_set_callback (source,
1494                              (GSourceFunc) write_async_pollable_ready,
1495                              g_object_ref (result), g_object_unref);
1496       g_source_set_priority (source, op->io_priority);
1497       g_source_attach (source, g_main_context_get_thread_default ());
1498       g_source_unref (source);
1499       return;
1500     }
1501
1502   if (op->count_written == -1)
1503     g_simple_async_result_take_error (result, error);
1504
1505   if (op->need_idle)
1506     g_simple_async_result_complete_in_idle (result);
1507   else
1508     g_simple_async_result_complete (result);
1509 }
1510
1511 static void
1512 g_output_stream_real_write_async (GOutputStream       *stream,
1513                                   const void          *buffer,
1514                                   gsize                count,
1515                                   int                  io_priority,
1516                                   GCancellable        *cancellable,
1517                                   GAsyncReadyCallback  callback,
1518                                   gpointer             user_data)
1519 {
1520   GSimpleAsyncResult *res;
1521   WriteData *op;
1522
1523   op = g_slice_new0 (WriteData);
1524   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1525   g_simple_async_result_set_op_res_gpointer (res, op, (GDestroyNotify) free_write_data);
1526   op->buffer = buffer;
1527   op->count_requested = count;
1528   op->cancellable = cancellable ? g_object_ref (cancellable) : NULL;
1529   op->io_priority = io_priority;
1530   op->need_idle = TRUE;
1531
1532   if (G_IS_POLLABLE_OUTPUT_STREAM (stream) &&
1533       g_pollable_output_stream_can_poll (G_POLLABLE_OUTPUT_STREAM (stream)))
1534     write_async_pollable (G_POLLABLE_OUTPUT_STREAM (stream), res);
1535   else
1536     g_simple_async_result_run_in_thread (res, write_async_thread, io_priority, cancellable);
1537   g_object_unref (res);
1538 }
1539
1540 static gssize
1541 g_output_stream_real_write_finish (GOutputStream  *stream,
1542                                    GAsyncResult   *result,
1543                                    GError        **error)
1544 {
1545   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1546   WriteData *op;
1547
1548   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_write_async);
1549   op = g_simple_async_result_get_op_res_gpointer (simple);
1550   return op->count_written;
1551 }
1552
1553 typedef struct {
1554   GInputStream *source;
1555   GOutputStreamSpliceFlags flags;
1556   gssize bytes_copied;
1557 } SpliceData;
1558
1559 static void
1560 splice_async_thread (GSimpleAsyncResult *result,
1561                      GObject            *object,
1562                      GCancellable       *cancellable)
1563 {
1564   SpliceData *op;
1565   GOutputStreamClass *class;
1566   GError *error = NULL;
1567   GOutputStream *stream;
1568
1569   stream = G_OUTPUT_STREAM (object);
1570   class = G_OUTPUT_STREAM_GET_CLASS (object);
1571   op = g_simple_async_result_get_op_res_gpointer (result);
1572
1573   op->bytes_copied = class->splice (stream,
1574                                     op->source,
1575                                     op->flags,
1576                                     cancellable,
1577                                     &error);
1578   if (op->bytes_copied == -1)
1579     g_simple_async_result_take_error (result, error);
1580 }
1581
1582 static void
1583 g_output_stream_real_splice_async (GOutputStream             *stream,
1584                                    GInputStream              *source,
1585                                    GOutputStreamSpliceFlags   flags,
1586                                    int                        io_priority,
1587                                    GCancellable              *cancellable,
1588                                    GAsyncReadyCallback        callback,
1589                                    gpointer                   user_data)
1590 {
1591   GSimpleAsyncResult *res;
1592   SpliceData *op;
1593
1594   op = g_new0 (SpliceData, 1);
1595   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_splice_async);
1596   g_simple_async_result_set_op_res_gpointer (res, op, g_free);
1597   op->flags = flags;
1598   op->source = source;
1599
1600   /* TODO: In the case where both source and destintion have
1601      non-threadbased async calls we can use a true async copy here */
1602
1603   g_simple_async_result_run_in_thread (res, splice_async_thread, io_priority, cancellable);
1604   g_object_unref (res);
1605 }
1606
1607 static gssize
1608 g_output_stream_real_splice_finish (GOutputStream  *stream,
1609                                     GAsyncResult   *result,
1610                                     GError        **error)
1611 {
1612   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1613   SpliceData *op;
1614
1615   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_splice_async);
1616   op = g_simple_async_result_get_op_res_gpointer (simple);
1617   return op->bytes_copied;
1618 }
1619
1620
1621 static void
1622 flush_async_thread (GSimpleAsyncResult *res,
1623                     GObject            *object,
1624                     GCancellable       *cancellable)
1625 {
1626   GOutputStreamClass *class;
1627   gboolean result;
1628   GError *error = NULL;
1629
1630   class = G_OUTPUT_STREAM_GET_CLASS (object);
1631   result = TRUE;
1632   if (class->flush)
1633     result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error);
1634
1635   if (!result)
1636     g_simple_async_result_take_error (res, error);
1637 }
1638
1639 static void
1640 g_output_stream_real_flush_async (GOutputStream       *stream,
1641                                   int                  io_priority,
1642                                   GCancellable        *cancellable,
1643                                   GAsyncReadyCallback  callback,
1644                                   gpointer             user_data)
1645 {
1646   GSimpleAsyncResult *res;
1647
1648   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1649
1650   g_simple_async_result_run_in_thread (res, flush_async_thread, io_priority, cancellable);
1651   g_object_unref (res);
1652 }
1653
1654 static gboolean
1655 g_output_stream_real_flush_finish (GOutputStream  *stream,
1656                                    GAsyncResult   *result,
1657                                    GError        **error)
1658 {
1659   return TRUE;
1660 }
1661
1662 static void
1663 close_async_thread (GSimpleAsyncResult *res,
1664                     GObject            *object,
1665                     GCancellable       *cancellable)
1666 {
1667   GOutputStreamClass *class;
1668   GError *error = NULL;
1669   gboolean result = TRUE;
1670
1671   class = G_OUTPUT_STREAM_GET_CLASS (object);
1672
1673   /* Do a flush here if there is a flush function, and we did not have to do
1674      an async flush before (see g_output_stream_close_async) */
1675   if (class->flush != NULL &&
1676       (class->flush_async == NULL ||
1677        class->flush_async == g_output_stream_real_flush_async))
1678     {
1679       result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error);
1680     }
1681
1682   /* Auto handling of cancelation disabled, and ignore
1683      cancellation, since we want to close things anyway, although
1684      possibly in a quick-n-dirty way. At least we never want to leak
1685      open handles */
1686
1687   if (class->close_fn)
1688     {
1689       /* Make sure to close, even if the flush failed (see sync close) */
1690       if (!result)
1691         class->close_fn (G_OUTPUT_STREAM (object), cancellable, NULL);
1692       else
1693         result = class->close_fn (G_OUTPUT_STREAM (object), cancellable, &error);
1694
1695       if (!result)
1696         g_simple_async_result_take_error (res, error);
1697     }
1698 }
1699
1700 static void
1701 g_output_stream_real_close_async (GOutputStream       *stream,
1702                                   int                  io_priority,
1703                                   GCancellable        *cancellable,
1704                                   GAsyncReadyCallback  callback,
1705                                   gpointer             user_data)
1706 {
1707   GSimpleAsyncResult *res;
1708
1709   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_close_async);
1710
1711   g_simple_async_result_set_handle_cancellation (res, FALSE);
1712
1713   g_simple_async_result_run_in_thread (res, close_async_thread, io_priority, cancellable);
1714   g_object_unref (res);
1715 }
1716
1717 static gboolean
1718 g_output_stream_real_close_finish (GOutputStream  *stream,
1719                                    GAsyncResult   *result,
1720                                    GError        **error)
1721 {
1722   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1723   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_close_async);
1724   return TRUE;
1725 }