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