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   GOutputStreamClass *class = G_OUTPUT_STREAM_GET_CLASS (stream);
 427   gssize n_read, n_written;
 428   gssize bytes_copied;
 429   char buffer[8192], *p;
 430   gboolean res;
 431
 432   if (class->write == NULL)
 433     {
 434       g_set_error (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
 435                    _("Output stream doesn't implement write"));
 436       res = FALSE;
 437       goto notsupported;
 438     }
 439
 440   bytes_copied = 0;
 441   res = TRUE;
 442   do
 443     {
 444       n_read = g_input_stream_read (source, buffer, sizeof (buffer), cancellable, error);
 445       if (n_read == -1)
 446         {
 447           res = FALSE;
 448           break;
 449         }
 450
 451       if (n_read == 0)
 452         break;
 453
 454       p = buffer;
 455       while (n_read > 0)
 456         {
 457           n_written = class->write (stream, p, n_read, cancellable, error);
 458           if (n_written == -1)
 459             {
 460               res = FALSE;
 461               break;
 462             }
 463
 464           p += n_written;
 465           n_read -= n_written;
 466           bytes_copied += n_written;
 467         }
 468     }
 469   while (res);
 470
 471  notsupported:
 472   if (!res)
 473     error = NULL; /* Ignore further errors */
 474
 475   if (flags & G_OUTPUT_STREAM_SPLICE_FLAGS_CLOSE_SOURCE)
 476     {
 477       /* Don't care about errors in source here */
 478       g_input_stream_close (source, cancellable, NULL);
 479     }
 480
 481   if (flags & G_OUTPUT_STREAM_SPLICE_FLAGS_CLOSE_TARGET)
 482     {
 483       /* But write errors on close are bad! */
 484       if (!class->close (stream, cancellable, error))
 485         res = FALSE;
 486     }
 487
 488   if (res)
 489     return bytes_copied;
 490
 491   return -1;
 492 }
 493
 494
 495 /**
 496  * g_output_stream_close:
 497  * @stream: A #GOutputStream.
 498  * @cancellable: optional cancellable object
 499  * @error: location to store the error occuring, or %NULL to ignore
 500  *
 501  * Closes the stream, releasing resources related to it.
 502  *
 503  * Once the stream is closed, all other operations will return %G_IO_ERROR_CLOSED.
 504  * Closing a stream multiple times will not return an error.
 505  *
 506  * Closing a stream will automatically flush any outstanding buffers in the
 507  * stream.
 508  *
 509  * Streams will be automatically closed when the last reference
 510  * is dropped, but you might want to call make sure resources
 511  * are released as early as possible.
 512  *
 513  * Some streams might keep the backing store of the stream (e.g. a file descriptor)
 514  * open after the stream is closed. See the documentation for the individual
 515  * stream for details.
 516  *
 517  * On failure the first error that happened will be reported, but the close
 518  * operation will finish as much as possible. A stream that failed to
 519  * close will still return %G_IO_ERROR_CLOSED all operations. Still, it
 520  * is important to check and report the error to the user, otherwise
 521  * there might be a loss of data as all data might not be written.
 522  *
 523  * If @cancellable is not NULL, then the operation can be cancelled by
 524  * triggering the cancellable object from another thread. If the operation
 525  * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
 526  * Cancelling a close will still leave the stream closed, but there some streams
 527  * can use a faster close that doesn't block to e.g. check errors. On
 528  * cancellation (as with any error) there is no guarantee that all written
 529  * data will reach the target.
 530  *
 531  * Return value: %TRUE on success, %FALSE on failure
 532  **/
 533 gboolean
 534 g_output_stream_close (GOutputStream  *stream,
 535                        GCancellable   *cancellable,
 536                        GError        **error)
 537 {
 538   GOutputStreamClass *class;
 539   gboolean res;
 540
 541   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 542
 543   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 544
 545   if (stream->priv->closed)
 546     return TRUE;
 547
 548   if (stream->priv->pending)
 549     {
 550       g_set_error (error, G_IO_ERROR, G_IO_ERROR_PENDING,
 551                    _("Stream has outstanding operation"));
 552       return FALSE;
 553     }
 554
 555   stream->priv->pending = TRUE;
 556
 557   if (cancellable)
 558     g_push_current_cancellable (cancellable);
 559
 560   res = class->flush (stream, cancellable, error);
 561
 562   if (!res)
 563     {
 564       /* flushing caused the error that we want to return,
 565        * but we still want to close the underlying stream if possible
 566        */
 567       if (class->close)
 568         class->close (stream, cancellable, NULL);
 569     }
 570   else
 571     {
 572       res = TRUE;
 573       if (class->close)
 574         res = class->close (stream, cancellable, error);
 575     }
 576
 577   if (cancellable)
 578     g_pop_current_cancellable (cancellable);
 579
 580   stream->priv->closed = TRUE;
 581   stream->priv->pending = FALSE;
 582
 583   return res;
 584 }
 585
 586 static void
 587 async_ready_callback_wrapper (GObject      *source_object,
 588                               GAsyncResult *res,
 589                               gpointer      user_data)
 590 {
 591   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 592
 593   stream->priv->pending = FALSE;
 594   if (stream->priv->outstanding_callback)
 595     (*stream->priv->outstanding_callback) (source_object, res, user_data);
 596   g_object_unref (stream);
 597 }
 598
 599 static void
 600 async_ready_close_callback_wrapper (GObject      *source_object,
 601                                     GAsyncResult *res,
 602                                     gpointer      user_data)
 603 {
 604   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 605
 606   stream->priv->pending = FALSE;
 607   stream->priv->closed = TRUE;
 608   if (stream->priv->outstanding_callback)
 609     (*stream->priv->outstanding_callback) (source_object, res, user_data);
 610   g_object_unref (stream);
 611 }
 612
 613 /**
 614  * g_output_stream_write_async:
 615  * @stream: A #GOutputStream.
 616  * @buffer: the buffer containing the data to write.
 617  * @count: the number of bytes to write
 618  * @io_priority: the io priority of the request.
 619  * @cancellable: optional #GCancellable object, %NULL to ignore.
 620  * @callback: callback to call when the request is satisfied
 621  * @user_data: the data to pass to callback function
 622  *
 623  * Request an asynchronous write of @count bytes from @buffer into
 624  * the stream. When the operation is finished @callback will be called,
 625  * giving the results.
 626  *
 627  * During an async request no other sync and async calls are allowed,
 628  * and will result in %G_IO_ERROR_PENDING errors.
 629  *
 630  * A value of @count larger than %G_MAXSSIZE will cause a
 631  * %G_IO_ERROR_INVALID_ARGUMENT error.
 632  *
 633  * On success, the number of bytes written will be passed to the
 634  * @callback. It is not an error if this is not the same as the
 635  * requested size, as it can happen e.g. on a partial I/O error,
 636  * but generally we try to write as many bytes as requested.
 637  *
 638  * Any outstanding I/O request with higher priority (lower numerical
 639  * value) will be executed before an outstanding request with lower
 640  * priority. Default priority is %G_PRIORITY_DEFAULT.
 641  *
 642  * The asyncronous methods have a default fallback that uses threads
 643  * to implement asynchronicity, so they are optional for inheriting
 644  * classes. However, if you override one you must override all.
 645  *
 646  * For the synchronous, blocking version of this function, see
 647  * g_output_stream_write().
 648  **/
 649 void
 650 g_output_stream_write_async (GOutputStream       *stream,
 651                              const void          *buffer,
 652                              gsize                count,
 653                              int                  io_priority,
 654                              GCancellable        *cancellable,
 655                              GAsyncReadyCallback  callback,
 656                              gpointer             user_data)
 657 {
 658   GOutputStreamClass *class;
 659   GSimpleAsyncResult *simple;
 660
 661   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 662   g_return_if_fail (buffer != NULL);
 663
 664   if (count == 0)
 665     {
 666       simple = g_simple_async_result_new (G_OBJECT (stream),
 667                                           callback,
 668                                           user_data,
 669                                           g_output_stream_write_async);
 670       g_simple_async_result_complete_in_idle (simple);
 671       g_object_unref (simple);
 672       return;
 673     }
 674
 675   if (((gssize) count) < 0)
 676     {
 677       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 678                                            callback,
 679                                            user_data,
 680                                            G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 681                                            _("Too large count value passed to g_output_stream_write_async"));
 682       return;
 683     }
 684
 685   if (stream->priv->closed)
 686     {
 687       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 688                                            callback,
 689                                            user_data,
 690                                            G_IO_ERROR, G_IO_ERROR_CLOSED,
 691                                            _("Stream is already closed"));
 692       return;
 693     }
 694
 695   if (stream->priv->pending)
 696     {
 697       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 698                                            callback,
 699                                            user_data,
 700                                            G_IO_ERROR, G_IO_ERROR_PENDING,
 701                                            _("Stream has outstanding operation"));
 702       return;
 703     }
 704
 705   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 706
 707   stream->priv->pending = TRUE;
 708   stream->priv->outstanding_callback = callback;
 709   g_object_ref (stream);
 710   class->write_async (stream, buffer, count, io_priority, cancellable,
 711                       async_ready_callback_wrapper, user_data);
 712 }
 713
 714 /**
 715  * g_output_stream_write_finish:
 716  * @stream: a #GOutputStream.
 717  * @result: a #GAsyncResult.
 718  * @error: a #GError location to store the error occuring, or %NULL to
 719  * ignore.
 720  *
 721  * Finishes a stream write operation.
 722  *
 723  * Returns: a #gssize containing the number of bytes written to the stream.
 724  **/
 725 gssize
 726 g_output_stream_write_finish (GOutputStream  *stream,
 727                               GAsyncResult   *result,
 728                               GError        **error)
 729 {
 730   GSimpleAsyncResult *simple;
 731   GOutputStreamClass *class;
 732
 733   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 734   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
 735
 736   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 737     {
 738       simple = G_SIMPLE_ASYNC_RESULT (result);
 739       if (g_simple_async_result_propagate_error (simple, error))
 740         return -1;
 741
 742       /* Special case writes of 0 bytes */
 743       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_write_async)
 744         return 0;
 745     }
 746
 747   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 748   return class->write_finish (stream, result, error);
 749 }
 750
 751 typedef struct {
 752   GInputStream *source;
 753   gpointer user_data;
 754   GAsyncReadyCallback callback;
 755 } SpliceUserData;
 756
 757 static void
 758 async_ready_splice_callback_wrapper (GObject      *source_object,
 759                                      GAsyncResult *res,
 760                                      gpointer     _data)
 761 {
 762   GOutputStream *stream = G_OUTPUT_STREAM (source_object);
 763   SpliceUserData *data = _data;
 764
 765   stream->priv->pending = FALSE;
 766
 767   if (data->callback)
 768     (*data->callback) (source_object, res, data->user_data);
 769
 770   g_object_unref (stream);
 771   g_object_unref (data->source);
 772   g_free (data);
 773 }
 774
 775 /**
 776  * g_output_stream_splice_async:
 777  * @stream: a #GOutputStream.
 778  * @source: a #GInputStream.
 779  * @flags: a set of #GOutputStreamSpliceFlags.
 780  * @io_priority: the io priority of the request.
 781  * @cancellable: optional #GCancellable object, %NULL to ignore.
 782  * @callback: a #GAsyncReadyCallback.
 783  * @user_data: user data passed to @callback.
 784  *
 785  * Splices a stream asynchronously.
 786  *
 787  **/
 788 void
 789 g_output_stream_splice_async (GOutputStream            *stream,
 790                               GInputStream             *source,
 791                               GOutputStreamSpliceFlags  flags,
 792                               int                       io_priority,
 793                               GCancellable             *cancellable,
 794                               GAsyncReadyCallback       callback,
 795                               gpointer                  user_data)
 796 {
 797   GOutputStreamClass *class;
 798   SpliceUserData *data;
 799
 800   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 801   g_return_if_fail (G_IS_INPUT_STREAM (source));
 802
 803   if (stream->priv->closed)
 804     {
 805       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 806                                            callback,
 807                                            user_data,
 808                                            G_IO_ERROR, G_IO_ERROR_CLOSED,
 809                                            _("Target stream is already closed"));
 810       return;
 811     }
 812
 813   if (g_input_stream_is_closed (source))
 814     {
 815       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 816                                            callback,
 817                                            user_data,
 818                                            G_IO_ERROR, G_IO_ERROR_CLOSED,
 819                                            _("Source stream is already closed"));
 820       return;
 821     }
 822
 823   if (stream->priv->pending)
 824     {
 825       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 826                                            callback,
 827                                            user_data,
 828                                            G_IO_ERROR, G_IO_ERROR_PENDING,
 829                                            _("Stream has outstanding operation"));
 830       return;
 831     }
 832
 833   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 834
 835   stream->priv->pending = TRUE;
 836
 837   data = g_new0 (SpliceUserData, 1);
 838   data->callback = callback;
 839   data->user_data = user_data;
 840   data->source = g_object_ref (source);
 841
 842   g_object_ref (stream);
 843   class->splice_async (stream, source, flags, io_priority, cancellable,
 844                       async_ready_splice_callback_wrapper, data);
 845 }
 846
 847 /**
 848  * g_output_stream_splice_finish:
 849  * @stream: a #GOutputStream.
 850  * @result: a #GAsyncResult.
 851  * @error: a #GError location to store the error occuring, or %NULL to
 852  * ignore.
 853  *
 854  * Finishes an asynchronous stream splice operation.
 855  *
 856  * Returns: a #gssize of the number of bytes spliced.
 857  **/
 858 gssize
 859 g_output_stream_splice_finish (GOutputStream  *stream,
 860                                GAsyncResult   *result,
 861                                GError        **error)
 862 {
 863   GSimpleAsyncResult *simple;
 864   GOutputStreamClass *class;
 865
 866   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1);
 867   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
 868
 869   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 870     {
 871       simple = G_SIMPLE_ASYNC_RESULT (result);
 872       if (g_simple_async_result_propagate_error (simple, error))
 873         return -1;
 874     }
 875
 876   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 877   return class->splice_finish (stream, result, error);
 878 }
 879
 880 /**
 881  * g_output_stream_flush_async:
 882  * @stream: a #GOutputStream.
 883  * @io_priority: the io priority of the request.
 884  * @cancellable: optional #GCancellable object, %NULL to ignore.
 885  * @callback: a #GAsyncReadyCallback to call when the request is satisfied
 886  * @user_data: the data to pass to callback function
 887  *
 888  * Flushes a stream asynchronously.
 889  *
 890  **/
 891 void
 892 g_output_stream_flush_async (GOutputStream       *stream,
 893                              int                  io_priority,
 894                              GCancellable        *cancellable,
 895                              GAsyncReadyCallback  callback,
 896                              gpointer             user_data)
 897 {
 898   GOutputStreamClass *class;
 899   GSimpleAsyncResult *simple;
 900
 901   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
 902
 903   if (stream->priv->closed)
 904     {
 905       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 906                                            callback,
 907                                            user_data,
 908                                            G_IO_ERROR, G_IO_ERROR_CLOSED,
 909                                            _("Stream is already closed"));
 910       return;
 911     }
 912
 913   if (stream->priv->pending)
 914     {
 915       g_simple_async_report_error_in_idle (G_OBJECT (stream),
 916                                            callback,
 917                                            user_data,
 918                                            G_IO_ERROR, G_IO_ERROR_PENDING,
 919                                            _("Stream has outstanding operation"));
 920       return;
 921     }
 922
 923   class = G_OUTPUT_STREAM_GET_CLASS (stream);
 924
 925   if (class->flush_async == NULL)
 926     {
 927       simple = g_simple_async_result_new (G_OBJECT (stream),
 928                                           callback,
 929                                           user_data,
 930                                           g_output_stream_flush_async);
 931       g_simple_async_result_complete_in_idle (simple);
 932       g_object_unref (simple);
 933       return;
 934     }
 935
 936   stream->priv->pending = TRUE;
 937   stream->priv->outstanding_callback = callback;
 938   g_object_ref (stream);
 939   class->flush_async (stream, io_priority, cancellable,
 940                       async_ready_callback_wrapper, user_data);
 941 }
 942
 943 /**
 944  * g_output_stream_flush_finish:
 945  * @stream: a #GOutputStream.
 946  * @result: a GAsyncResult.
 947  * @error: a #GError location to store the error occuring, or %NULL to
 948  * ignore.
 949  *
 950  * Finishes flushing an output stream.
 951  *
 952  * Returns: %TRUE if flush operation suceeded, %FALSE otherwise.
 953  **/
 954 gboolean
 955 g_output_stream_flush_finish (GOutputStream  *stream,
 956                               GAsyncResult   *result,
 957                               GError        **error)
 958 {
 959   GSimpleAsyncResult *simple;
 960   GOutputStreamClass *klass;
 961
 962   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
 963   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
 964
 965   if (G_IS_SIMPLE_ASYNC_RESULT (result))
 966     {
 967       simple = G_SIMPLE_ASYNC_RESULT (result);
 968       if (g_simple_async_result_propagate_error (simple, error))
 969         return FALSE;
 970
 971       /* Special case default implementation */
 972       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_flush_async)
 973         return TRUE;
 974     }
 975
 976   klass = G_OUTPUT_STREAM_GET_CLASS (stream);
 977   return klass->flush_finish (stream, result, error);
 978 }
 979
 980
 981 /**
 982  * g_output_stream_close_async:
 983  * @stream: A #GOutputStream.
 984  * @io_priority: the io priority of the request.
 985  * @callback: callback to call when the request is satisfied
 986  * @user_data: the data to pass to callback function
 987  * @cancellable: optional cancellable object
 988  *
 989  * Requests an asynchronous close of the stream, releasing resources
 990  * related to it. When the operation is finished @callback will be
 991  * called, giving the results.
 992  *
 993  * For behaviour details see g_output_stream_close().
 994  *
 995  * The asyncronous methods have a default fallback that uses threads
 996  * to implement asynchronicity, so they are optional for inheriting
 997  * classes. However, if you override one you must override all.
 998  **/
 999 void
1000 g_output_stream_close_async (GOutputStream       *stream,
1001                              int                  io_priority,
1002                              GCancellable        *cancellable,
1003                              GAsyncReadyCallback  callback,
1004                              gpointer             user_data)
1005 {
1006   GOutputStreamClass *class;
1007   GSimpleAsyncResult *simple;
1008
1009   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1010
1011   if (stream->priv->closed)
1012     {
1013       simple = g_simple_async_result_new (G_OBJECT (stream),
1014                                           callback,
1015                                           user_data,
1016                                           g_output_stream_close_async);
1017       g_simple_async_result_complete_in_idle (simple);
1018       g_object_unref (simple);
1019       return;
1020     }
1021
1022   if (stream->priv->pending)
1023     {
1024       g_simple_async_report_error_in_idle (G_OBJECT (stream),
1025                                            callback,
1026                                            user_data,
1027                                            G_IO_ERROR, G_IO_ERROR_PENDING,
1028                                            _("Stream has outstanding operation"));
1029       return;
1030     }
1031
1032   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1033   stream->priv->pending = TRUE;
1034   stream->priv->outstanding_callback = callback;
1035   g_object_ref (stream);
1036   class->close_async (stream, io_priority, cancellable,
1037                       async_ready_close_callback_wrapper, user_data);
1038 }
1039
1040 /**
1041  * g_output_stream_close_finish:
1042  * @stream: a #GOutputStream.
1043  * @result: a #GAsyncResult.
1044  * @error: a #GError location to store the error occuring, or %NULL to
1045  * ignore.
1046  *
1047  * Closes an output stream.
1048  *
1049  * Returns: %TRUE if stream was successfully closed, %FALSE otherwise.
1050  **/
1051 gboolean
1052 g_output_stream_close_finish (GOutputStream  *stream,
1053                               GAsyncResult   *result,
1054                               GError        **error)
1055 {
1056   GSimpleAsyncResult *simple;
1057   GOutputStreamClass *class;
1058
1059   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1060   g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
1061
1062   if (G_IS_SIMPLE_ASYNC_RESULT (result))
1063     {
1064       simple = G_SIMPLE_ASYNC_RESULT (result);
1065       if (g_simple_async_result_propagate_error (simple, error))
1066         return FALSE;
1067
1068       /* Special case already closed */
1069       if (g_simple_async_result_get_source_tag (simple) == g_output_stream_close_async)
1070         return TRUE;
1071     }
1072
1073   class = G_OUTPUT_STREAM_GET_CLASS (stream);
1074   return class->close_finish (stream, result, error);
1075 }
1076
1077 /**
1078  * g_output_stream_is_closed:
1079  * @stream: a #GOutputStream.
1080  *
1081  * Checks if an output stream has already been closed.
1082  *
1083  * Returns: %TRUE if @stream is closed. %FALSE otherwise.
1084  **/
1085 gboolean
1086 g_output_stream_is_closed (GOutputStream *stream)
1087 {
1088   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE);
1089
1090   return stream->priv->closed;
1091 }
1092
1093 /**
1094  * g_output_stream_has_pending:
1095  * @stream: a #GOutputStream.
1096  *
1097  * Checks if an ouput stream has pending actions.
1098  *
1099  * Returns: %TRUE if @stream has pending actions.
1100  **/
1101 gboolean
1102 g_output_stream_has_pending (GOutputStream *stream)
1103 {
1104   g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE);
1105
1106   return stream->priv->pending;
1107 }
1108
1109 /**
1110  * g_output_stream_set_pending:
1111  * @stream: a #GOutputStream.
1112  * @pending: a #gboolean.
1113  *
1114  * Sets the @stream as having pending actions if @pending is %TRUE.
1115  **/
1116 void
1117 g_output_stream_set_pending (GOutputStream *stream,
1118                             gboolean        pending)
1119 {
1120   g_return_if_fail (G_IS_OUTPUT_STREAM (stream));
1121
1122   stream->priv->pending = pending;
1123 }
1124
1125
1126 /********************************************
1127  *   Default implementation of async ops    *
1128  ********************************************/
1129
1130 typedef struct {
1131   const void         *buffer;
1132   gsize               count_requested;
1133   gssize              count_written;
1134 } WriteData;
1135
1136 static void
1137 write_async_thread (GSimpleAsyncResult *res,
1138                     GObject            *object,
1139                     GCancellable       *cancellable)
1140 {
1141   WriteData *op;
1142   GOutputStreamClass *class;
1143   GError *error = NULL;
1144
1145   class = G_OUTPUT_STREAM_GET_CLASS (object);
1146   op = g_simple_async_result_get_op_res_gpointer (res);
1147   op->count_written = class->write (G_OUTPUT_STREAM (object), op->buffer, op->count_requested,
1148                                     cancellable, &error);
1149   if (op->count_written == -1)
1150     {
1151       g_simple_async_result_set_from_error (res, error);
1152       g_error_free (error);
1153     }
1154 }
1155
1156 static void
1157 g_output_stream_real_write_async (GOutputStream       *stream,
1158                                   const void          *buffer,
1159                                   gsize                count,
1160                                   int                  io_priority,
1161                                   GCancellable        *cancellable,
1162                                   GAsyncReadyCallback  callback,
1163                                   gpointer             user_data)
1164 {
1165   GSimpleAsyncResult *res;
1166   WriteData *op;
1167
1168   op = g_new0 (WriteData, 1);
1169   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1170   g_simple_async_result_set_op_res_gpointer (res, op, g_free);
1171   op->buffer = buffer;
1172   op->count_requested = count;
1173
1174   g_simple_async_result_run_in_thread (res, write_async_thread, io_priority, cancellable);
1175   g_object_unref (res);
1176 }
1177
1178 static gssize
1179 g_output_stream_real_write_finish (GOutputStream  *stream,
1180                                    GAsyncResult   *result,
1181                                    GError        **error)
1182 {
1183   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1184   WriteData *op;
1185
1186   g_assert (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_write_async);
1187   op = g_simple_async_result_get_op_res_gpointer (simple);
1188   return op->count_written;
1189 }
1190
1191 typedef struct {
1192   GInputStream *source;
1193   GOutputStreamSpliceFlags flags;
1194   gssize bytes_copied;
1195 } SpliceData;
1196
1197 static void
1198 splice_async_thread (GSimpleAsyncResult *result,
1199                      GObject            *object,
1200                      GCancellable       *cancellable)
1201 {
1202   SpliceData *op;
1203   GOutputStreamClass *class;
1204   GError *error = NULL;
1205   GOutputStream *stream;
1206
1207   stream = G_OUTPUT_STREAM (object);
1208   class = G_OUTPUT_STREAM_GET_CLASS (object);
1209   op = g_simple_async_result_get_op_res_gpointer (result);
1210
1211   op->bytes_copied = class->splice (stream,
1212                                     op->source,
1213                                     op->flags,
1214                                     cancellable,
1215                                     &error);
1216
1217   if (op->bytes_copied == -1)
1218     {
1219       g_simple_async_result_set_from_error (result, error);
1220       g_error_free (error);
1221     }
1222 }
1223
1224 static void
1225 g_output_stream_real_splice_async (GOutputStream             *stream,
1226                                    GInputStream              *source,
1227                                    GOutputStreamSpliceFlags   flags,
1228                                    int                        io_priority,
1229                                    GCancellable              *cancellable,
1230                                    GAsyncReadyCallback        callback,
1231                                    gpointer                   user_data)
1232 {
1233   GSimpleAsyncResult *res;
1234   SpliceData *op;
1235
1236   op = g_new0 (SpliceData, 1);
1237   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_splice_async);
1238   g_simple_async_result_set_op_res_gpointer (res, op, g_free);
1239   op->flags = flags;
1240   op->source = source;
1241
1242   /* TODO: In the case where both source and destintion have
1243      non-threadbased async calls we can use a true async copy here */
1244
1245   g_simple_async_result_run_in_thread (res, splice_async_thread, io_priority, cancellable);
1246   g_object_unref (res);
1247 }
1248
1249 static gssize
1250 g_output_stream_real_splice_finish (GOutputStream  *stream,
1251                                     GAsyncResult   *result,
1252                                     GError        **error)
1253 {
1254   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1255   SpliceData *op;
1256
1257   g_assert (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_splice_async);
1258   op = g_simple_async_result_get_op_res_gpointer (simple);
1259   return op->bytes_copied;
1260 }
1261
1262
1263 static void
1264 flush_async_thread (GSimpleAsyncResult *res,
1265                     GObject            *object,
1266                     GCancellable       *cancellable)
1267 {
1268   GOutputStreamClass *class;
1269   gboolean result;
1270   GError *error = NULL;
1271
1272   class = G_OUTPUT_STREAM_GET_CLASS (object);
1273   result = TRUE;
1274   if (class->flush)
1275     result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error);
1276
1277   if (!result)
1278     {
1279       g_simple_async_result_set_from_error (res, error);
1280       g_error_free (error);
1281     }
1282 }
1283
1284 static void
1285 g_output_stream_real_flush_async (GOutputStream       *stream,
1286                                   int                  io_priority,
1287                                   GCancellable        *cancellable,
1288                                   GAsyncReadyCallback  callback,
1289                                   gpointer             user_data)
1290 {
1291   GSimpleAsyncResult *res;
1292
1293   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async);
1294
1295   g_simple_async_result_run_in_thread (res, flush_async_thread, io_priority, cancellable);
1296   g_object_unref (res);
1297 }
1298
1299 static gboolean
1300 g_output_stream_real_flush_finish (GOutputStream  *stream,
1301                                    GAsyncResult   *result,
1302                                    GError        **error)
1303 {
1304   return TRUE;
1305 }
1306
1307 static void
1308 close_async_thread (GSimpleAsyncResult *res,
1309                     GObject            *object,
1310                     GCancellable       *cancellable)
1311 {
1312   GOutputStreamClass *class;
1313   GError *error = NULL;
1314   gboolean result;
1315
1316   /* Auto handling of cancelation disabled, and ignore
1317      cancellation, since we want to close things anyway, although
1318      possibly in a quick-n-dirty way. At least we never want to leak
1319      open handles */
1320
1321   class = G_OUTPUT_STREAM_GET_CLASS (object);
1322   result = class->close (G_OUTPUT_STREAM (object), cancellable, &error);
1323   if (!result)
1324     {
1325       g_simple_async_result_set_from_error (res, error);
1326       g_error_free (error);
1327     }
1328 }
1329
1330 static void
1331 g_output_stream_real_close_async (GOutputStream       *stream,
1332                                   int                  io_priority,
1333                                   GCancellable        *cancellable,
1334                                   GAsyncReadyCallback  callback,
1335                                   gpointer             user_data)
1336 {
1337   GSimpleAsyncResult *res;
1338
1339   res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_close_async);
1340
1341   g_simple_async_result_set_handle_cancellation (res, FALSE);
1342
1343   g_simple_async_result_run_in_thread (res, close_async_thread, io_priority, cancellable);
1344   g_object_unref (res);
1345 }
1346
1347 static gboolean
1348 g_output_stream_real_close_finish (GOutputStream  *stream,
1349                                    GAsyncResult   *result,
1350                                    GError        **error)
1351 {
1352   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
1353   g_assert (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_close_async);
1354   return TRUE;
1355 }
1356
1357 #define __G_OUTPUT_STREAM_C__
1358 #include "gioaliasdef.c"