1 /* GIO - GLib Input, Output and Streaming Library
3 * Copyright (C) 2006-2007 Red Hat, Inc.
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.
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.
15 * You should have received a copy of the GNU Lesser General
16 * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 * Author: Alexander Larsson <alexl@redhat.com>
25 #include "ginputstream.h"
26 #include "gioprivate.h"
27 #include "gseekable.h"
28 #include "gcancellable.h"
29 #include "gasyncresult.h"
31 #include "gpollableinputstream.h"
34 * SECTION:ginputstream
35 * @short_description: Base class for implementing streaming input
38 * #GInputStream has functions to read from a stream (g_input_stream_read()),
39 * to close a stream (g_input_stream_close()) and to skip some content
40 * (g_input_stream_skip()).
42 * To copy the content of an input stream to an output stream without
43 * manually handling the reads and writes, use g_output_stream_splice().
45 * All of these functions have async variants too.
48 struct _GInputStreamPrivate {
51 GAsyncReadyCallback outstanding_callback;
54 G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GInputStream, g_input_stream, G_TYPE_OBJECT)
56 static gssize g_input_stream_real_skip (GInputStream *stream,
58 GCancellable *cancellable,
60 static void g_input_stream_real_read_async (GInputStream *stream,
64 GCancellable *cancellable,
65 GAsyncReadyCallback callback,
67 static gssize g_input_stream_real_read_finish (GInputStream *stream,
70 static void g_input_stream_real_skip_async (GInputStream *stream,
73 GCancellable *cancellable,
74 GAsyncReadyCallback callback,
76 static gssize g_input_stream_real_skip_finish (GInputStream *stream,
79 static void g_input_stream_real_close_async (GInputStream *stream,
81 GCancellable *cancellable,
82 GAsyncReadyCallback callback,
84 static gboolean g_input_stream_real_close_finish (GInputStream *stream,
89 g_input_stream_dispose (GObject *object)
93 stream = G_INPUT_STREAM (object);
95 if (!stream->priv->closed)
96 g_input_stream_close (stream, NULL, NULL);
98 G_OBJECT_CLASS (g_input_stream_parent_class)->dispose (object);
103 g_input_stream_class_init (GInputStreamClass *klass)
105 GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
107 gobject_class->dispose = g_input_stream_dispose;
109 klass->skip = g_input_stream_real_skip;
110 klass->read_async = g_input_stream_real_read_async;
111 klass->read_finish = g_input_stream_real_read_finish;
112 klass->skip_async = g_input_stream_real_skip_async;
113 klass->skip_finish = g_input_stream_real_skip_finish;
114 klass->close_async = g_input_stream_real_close_async;
115 klass->close_finish = g_input_stream_real_close_finish;
119 g_input_stream_init (GInputStream *stream)
121 stream->priv = g_input_stream_get_instance_private (stream);
125 * g_input_stream_read:
126 * @stream: a #GInputStream.
127 * @buffer: (array length=count) (element-type guint8): a buffer to
128 * read data into (which should be at least count bytes long).
129 * @count: the number of bytes that will be read from the stream
130 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
131 * @error: location to store the error occurring, or %NULL to ignore
133 * Tries to read @count bytes from the stream into the buffer starting at
134 * @buffer. Will block during this read.
136 * If count is zero returns zero and does nothing. A value of @count
137 * larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
139 * On success, the number of bytes read into the buffer is returned.
140 * It is not an error if this is not the same as the requested size, as it
141 * can happen e.g. near the end of a file. Zero is returned on end of file
142 * (or if @count is zero), but never otherwise.
144 * The returned @buffer is not a nul-terminated string, it can contain nul bytes
145 * at any position, and this function doesn't nul-terminate the @buffer.
147 * If @cancellable is not %NULL, then the operation can be cancelled by
148 * triggering the cancellable object from another thread. If the operation
149 * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an
150 * operation was partially finished when the operation was cancelled the
151 * partial result will be returned, without an error.
153 * On error -1 is returned and @error is set accordingly.
155 * Returns: Number of bytes read, or -1 on error, or 0 on end of file.
158 g_input_stream_read (GInputStream *stream,
161 GCancellable *cancellable,
164 GInputStreamClass *class;
167 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), -1);
168 g_return_val_if_fail (buffer != NULL, 0);
173 if (((gssize) count) < 0)
175 g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
176 _("Too large count value passed to %s"), G_STRFUNC);
180 class = G_INPUT_STREAM_GET_CLASS (stream);
182 if (class->read_fn == NULL)
184 g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
185 _("Input stream doesn't implement read"));
189 if (!g_input_stream_set_pending (stream, error))
193 g_cancellable_push_current (cancellable);
195 res = class->read_fn (stream, buffer, count, cancellable, error);
198 g_cancellable_pop_current (cancellable);
200 g_input_stream_clear_pending (stream);
206 * g_input_stream_read_all:
207 * @stream: a #GInputStream.
208 * @buffer: (array length=count) (element-type guint8): a buffer to
209 * read data into (which should be at least count bytes long).
210 * @count: the number of bytes that will be read from the stream
211 * @bytes_read: (out): location to store the number of bytes that was read from the stream
212 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
213 * @error: location to store the error occurring, or %NULL to ignore
215 * Tries to read @count bytes from the stream into the buffer starting at
216 * @buffer. Will block during this read.
218 * This function is similar to g_input_stream_read(), except it tries to
219 * read as many bytes as requested, only stopping on an error or end of stream.
221 * On a successful read of @count bytes, or if we reached the end of the
222 * stream, %TRUE is returned, and @bytes_read is set to the number of bytes
225 * If there is an error during the operation %FALSE is returned and @error
226 * is set to indicate the error status, @bytes_read is updated to contain
227 * the number of bytes read into @buffer before the error occurred.
229 * Returns: %TRUE on success, %FALSE if there was an error
232 g_input_stream_read_all (GInputStream *stream,
236 GCancellable *cancellable,
242 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);
243 g_return_val_if_fail (buffer != NULL, FALSE);
246 while (_bytes_read < count)
248 res = g_input_stream_read (stream, (char *)buffer + _bytes_read, count - _bytes_read,
253 *bytes_read = _bytes_read;
264 *bytes_read = _bytes_read;
269 * g_input_stream_read_bytes:
270 * @stream: a #GInputStream.
271 * @count: maximum number of bytes that will be read from the stream. Common
272 * values include 4096 and 8192.
273 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
274 * @error: location to store the error occurring, or %NULL to ignore
276 * Like g_input_stream_read(), this tries to read @count bytes from
277 * the stream in a blocking fashion. However, rather than reading into
278 * a user-supplied buffer, this will create a new #GBytes containing
279 * the data that was read. This may be easier to use from language
282 * If count is zero, returns a zero-length #GBytes and does nothing. A
283 * value of @count larger than %G_MAXSSIZE will cause a
284 * %G_IO_ERROR_INVALID_ARGUMENT error.
286 * On success, a new #GBytes is returned. It is not an error if the
287 * size of this object is not the same as the requested size, as it
288 * can happen e.g. near the end of a file. A zero-length #GBytes is
289 * returned on end of file (or if @count is zero), but never
292 * If @cancellable is not %NULL, then the operation can be cancelled by
293 * triggering the cancellable object from another thread. If the operation
294 * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an
295 * operation was partially finished when the operation was cancelled the
296 * partial result will be returned, without an error.
298 * On error %NULL is returned and @error is set accordingly.
300 * Returns: a new #GBytes, or %NULL on error
303 g_input_stream_read_bytes (GInputStream *stream,
305 GCancellable *cancellable,
311 buf = g_malloc (count);
312 nread = g_input_stream_read (stream, buf, count, cancellable, error);
321 return g_bytes_new_static ("", 0);
324 return g_bytes_new_take (buf, nread);
328 * g_input_stream_skip:
329 * @stream: a #GInputStream.
330 * @count: the number of bytes that will be skipped from the stream
331 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
332 * @error: location to store the error occurring, or %NULL to ignore
334 * Tries to skip @count bytes from the stream. Will block during the operation.
336 * This is identical to g_input_stream_read(), from a behaviour standpoint,
337 * but the bytes that are skipped are not returned to the user. Some
338 * streams have an implementation that is more efficient than reading the data.
340 * This function is optional for inherited classes, as the default implementation
341 * emulates it using read.
343 * If @cancellable is not %NULL, then the operation can be cancelled by
344 * triggering the cancellable object from another thread. If the operation
345 * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an
346 * operation was partially finished when the operation was cancelled the
347 * partial result will be returned, without an error.
349 * Returns: Number of bytes skipped, or -1 on error
352 g_input_stream_skip (GInputStream *stream,
354 GCancellable *cancellable,
357 GInputStreamClass *class;
360 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), -1);
365 if (((gssize) count) < 0)
367 g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
368 _("Too large count value passed to %s"), G_STRFUNC);
372 class = G_INPUT_STREAM_GET_CLASS (stream);
374 if (!g_input_stream_set_pending (stream, error))
378 g_cancellable_push_current (cancellable);
380 res = class->skip (stream, count, cancellable, error);
383 g_cancellable_pop_current (cancellable);
385 g_input_stream_clear_pending (stream);
391 g_input_stream_real_skip (GInputStream *stream,
393 GCancellable *cancellable,
396 GInputStreamClass *class;
397 gssize ret, read_bytes;
401 if (G_IS_SEEKABLE (stream) && g_seekable_can_seek (G_SEEKABLE (stream)))
403 if (g_seekable_seek (G_SEEKABLE (stream),
411 /* If not seekable, or seek failed, fall back to reading data: */
413 class = G_INPUT_STREAM_GET_CLASS (stream);
420 ret = class->read_fn (stream, buffer, MIN (sizeof (buffer), count),
421 cancellable, &my_error);
424 if (read_bytes > 0 &&
425 my_error->domain == G_IO_ERROR &&
426 my_error->code == G_IO_ERROR_CANCELLED)
428 g_error_free (my_error);
432 g_propagate_error (error, my_error);
439 if (ret == 0 || count == 0)
445 * g_input_stream_close:
446 * @stream: A #GInputStream.
447 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
448 * @error: location to store the error occurring, or %NULL to ignore
450 * Closes the stream, releasing resources related to it.
452 * Once the stream is closed, all other operations will return %G_IO_ERROR_CLOSED.
453 * Closing a stream multiple times will not return an error.
455 * Streams will be automatically closed when the last reference
456 * is dropped, but you might want to call this function to make sure
457 * resources are released as early as possible.
459 * Some streams might keep the backing store of the stream (e.g. a file descriptor)
460 * open after the stream is closed. See the documentation for the individual
461 * stream for details.
463 * On failure the first error that happened will be reported, but the close
464 * operation will finish as much as possible. A stream that failed to
465 * close will still return %G_IO_ERROR_CLOSED for all operations. Still, it
466 * is important to check and report the error to the user.
468 * If @cancellable is not %NULL, then the operation can be cancelled by
469 * triggering the cancellable object from another thread. If the operation
470 * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned.
471 * Cancelling a close will still leave the stream closed, but some streams
472 * can use a faster close that doesn't block to e.g. check errors.
474 * Returns: %TRUE on success, %FALSE on failure
477 g_input_stream_close (GInputStream *stream,
478 GCancellable *cancellable,
481 GInputStreamClass *class;
484 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);
486 class = G_INPUT_STREAM_GET_CLASS (stream);
488 if (stream->priv->closed)
493 if (!g_input_stream_set_pending (stream, error))
497 g_cancellable_push_current (cancellable);
500 res = class->close_fn (stream, cancellable, error);
503 g_cancellable_pop_current (cancellable);
505 g_input_stream_clear_pending (stream);
507 stream->priv->closed = TRUE;
513 async_ready_callback_wrapper (GObject *source_object,
517 GInputStream *stream = G_INPUT_STREAM (source_object);
519 g_input_stream_clear_pending (stream);
520 if (stream->priv->outstanding_callback)
521 (*stream->priv->outstanding_callback) (source_object, res, user_data);
522 g_object_unref (stream);
526 async_ready_close_callback_wrapper (GObject *source_object,
530 GInputStream *stream = G_INPUT_STREAM (source_object);
532 g_input_stream_clear_pending (stream);
533 stream->priv->closed = TRUE;
534 if (stream->priv->outstanding_callback)
535 (*stream->priv->outstanding_callback) (source_object, res, user_data);
536 g_object_unref (stream);
540 * g_input_stream_read_async:
541 * @stream: A #GInputStream.
542 * @buffer: (array length=count) (element-type guint8): a buffer to
543 * read data into (which should be at least count bytes long).
544 * @count: the number of bytes that will be read from the stream
545 * @io_priority: the [I/O priority][io-priority]
547 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
548 * @callback: (scope async): callback to call when the request is satisfied
549 * @user_data: (closure): the data to pass to callback function
551 * Request an asynchronous read of @count bytes from the stream into the buffer
552 * starting at @buffer. When the operation is finished @callback will be called.
553 * You can then call g_input_stream_read_finish() to get the result of the
556 * During an async request no other sync and async calls are allowed on @stream, and will
557 * result in %G_IO_ERROR_PENDING errors.
559 * A value of @count larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
561 * On success, the number of bytes read into the buffer will be passed to the
562 * callback. It is not an error if this is not the same as the requested size, as it
563 * can happen e.g. near the end of a file, but generally we try to read
564 * as many bytes as requested. Zero is returned on end of file
565 * (or if @count is zero), but never otherwise.
567 * Any outstanding i/o request with higher priority (lower numerical value) will
568 * be executed before an outstanding request with lower priority. Default
569 * priority is %G_PRIORITY_DEFAULT.
571 * The asyncronous methods have a default fallback that uses threads to implement
572 * asynchronicity, so they are optional for inheriting classes. However, if you
573 * override one you must override all.
576 g_input_stream_read_async (GInputStream *stream,
580 GCancellable *cancellable,
581 GAsyncReadyCallback callback,
584 GInputStreamClass *class;
585 GError *error = NULL;
587 g_return_if_fail (G_IS_INPUT_STREAM (stream));
588 g_return_if_fail (buffer != NULL);
594 task = g_task_new (stream, cancellable, callback, user_data);
595 g_task_set_source_tag (task, g_input_stream_read_async);
596 g_task_return_int (task, 0);
597 g_object_unref (task);
601 if (((gssize) count) < 0)
603 g_task_report_new_error (stream, callback, user_data,
604 g_input_stream_read_async,
605 G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
606 _("Too large count value passed to %s"),
611 if (!g_input_stream_set_pending (stream, &error))
613 g_task_report_error (stream, callback, user_data,
614 g_input_stream_read_async,
619 class = G_INPUT_STREAM_GET_CLASS (stream);
620 stream->priv->outstanding_callback = callback;
621 g_object_ref (stream);
622 class->read_async (stream, buffer, count, io_priority, cancellable,
623 async_ready_callback_wrapper, user_data);
627 * g_input_stream_read_finish:
628 * @stream: a #GInputStream.
629 * @result: a #GAsyncResult.
630 * @error: a #GError location to store the error occurring, or %NULL to
633 * Finishes an asynchronous stream read operation.
635 * Returns: number of bytes read in, or -1 on error, or 0 on end of file.
638 g_input_stream_read_finish (GInputStream *stream,
639 GAsyncResult *result,
642 GInputStreamClass *class;
644 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), -1);
645 g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
647 if (g_async_result_legacy_propagate_error (result, error))
649 else if (g_async_result_is_tagged (result, g_input_stream_read_async))
650 return g_task_propagate_int (G_TASK (result), error);
652 class = G_INPUT_STREAM_GET_CLASS (stream);
653 return class->read_finish (stream, result, error);
657 read_bytes_callback (GObject *stream,
658 GAsyncResult *result,
661 GTask *task = user_data;
662 guchar *buf = g_task_get_task_data (task);
663 GError *error = NULL;
665 GBytes *bytes = NULL;
667 nread = g_input_stream_read_finish (G_INPUT_STREAM (stream),
672 g_task_return_error (task, error);
677 bytes = g_bytes_new_static ("", 0);
680 bytes = g_bytes_new_take (buf, nread);
683 g_task_return_pointer (task, bytes, (GDestroyNotify)g_bytes_unref);
685 g_object_unref (task);
689 * g_input_stream_read_bytes_async:
690 * @stream: A #GInputStream.
691 * @count: the number of bytes that will be read from the stream
692 * @io_priority: the [I/O priority][io-priority] of the request
693 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
694 * @callback: (scope async): callback to call when the request is satisfied
695 * @user_data: (closure): the data to pass to callback function
697 * Request an asynchronous read of @count bytes from the stream into a
698 * new #GBytes. When the operation is finished @callback will be
699 * called. You can then call g_input_stream_read_bytes_finish() to get the
700 * result of the operation.
702 * During an async request no other sync and async calls are allowed
703 * on @stream, and will result in %G_IO_ERROR_PENDING errors.
705 * A value of @count larger than %G_MAXSSIZE will cause a
706 * %G_IO_ERROR_INVALID_ARGUMENT error.
708 * On success, the new #GBytes will be passed to the callback. It is
709 * not an error if this is smaller than the requested size, as it can
710 * happen e.g. near the end of a file, but generally we try to read as
711 * many bytes as requested. Zero is returned on end of file (or if
712 * @count is zero), but never otherwise.
714 * Any outstanding I/O request with higher priority (lower numerical
715 * value) will be executed before an outstanding request with lower
716 * priority. Default priority is %G_PRIORITY_DEFAULT.
719 g_input_stream_read_bytes_async (GInputStream *stream,
722 GCancellable *cancellable,
723 GAsyncReadyCallback callback,
729 task = g_task_new (stream, cancellable, callback, user_data);
730 buf = g_malloc (count);
731 g_task_set_task_data (task, buf, NULL);
733 g_input_stream_read_async (stream, buf, count,
734 io_priority, cancellable,
735 read_bytes_callback, task);
739 * g_input_stream_read_bytes_finish:
740 * @stream: a #GInputStream.
741 * @result: a #GAsyncResult.
742 * @error: a #GError location to store the error occurring, or %NULL to
745 * Finishes an asynchronous stream read-into-#GBytes operation.
747 * Returns: the newly-allocated #GBytes, or %NULL on error
750 g_input_stream_read_bytes_finish (GInputStream *stream,
751 GAsyncResult *result,
754 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), NULL);
755 g_return_val_if_fail (g_task_is_valid (result, stream), NULL);
757 return g_task_propagate_pointer (G_TASK (result), error);
761 * g_input_stream_skip_async:
762 * @stream: A #GInputStream.
763 * @count: the number of bytes that will be skipped from the stream
764 * @io_priority: the [I/O priority][io-priority] of the request
765 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
766 * @callback: (scope async): callback to call when the request is satisfied
767 * @user_data: (closure): the data to pass to callback function
769 * Request an asynchronous skip of @count bytes from the stream.
770 * When the operation is finished @callback will be called.
771 * You can then call g_input_stream_skip_finish() to get the result
774 * During an async request no other sync and async calls are allowed,
775 * and will result in %G_IO_ERROR_PENDING errors.
777 * A value of @count larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error.
779 * On success, the number of bytes skipped will be passed to the callback.
780 * It is not an error if this is not the same as the requested size, as it
781 * can happen e.g. near the end of a file, but generally we try to skip
782 * as many bytes as requested. Zero is returned on end of file
783 * (or if @count is zero), but never otherwise.
785 * Any outstanding i/o request with higher priority (lower numerical value)
786 * will be executed before an outstanding request with lower priority.
787 * Default priority is %G_PRIORITY_DEFAULT.
789 * The asynchronous methods have a default fallback that uses threads to
790 * implement asynchronicity, so they are optional for inheriting classes.
791 * However, if you override one, you must override all.
794 g_input_stream_skip_async (GInputStream *stream,
797 GCancellable *cancellable,
798 GAsyncReadyCallback callback,
801 GInputStreamClass *class;
802 GError *error = NULL;
804 g_return_if_fail (G_IS_INPUT_STREAM (stream));
810 task = g_task_new (stream, cancellable, callback, user_data);
811 g_task_set_source_tag (task, g_input_stream_skip_async);
812 g_task_return_int (task, 0);
813 g_object_unref (task);
817 if (((gssize) count) < 0)
819 g_task_report_new_error (stream, callback, user_data,
820 g_input_stream_skip_async,
821 G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
822 _("Too large count value passed to %s"),
827 if (!g_input_stream_set_pending (stream, &error))
829 g_task_report_error (stream, callback, user_data,
830 g_input_stream_skip_async,
835 class = G_INPUT_STREAM_GET_CLASS (stream);
836 stream->priv->outstanding_callback = callback;
837 g_object_ref (stream);
838 class->skip_async (stream, count, io_priority, cancellable,
839 async_ready_callback_wrapper, user_data);
843 * g_input_stream_skip_finish:
844 * @stream: a #GInputStream.
845 * @result: a #GAsyncResult.
846 * @error: a #GError location to store the error occurring, or %NULL to
849 * Finishes a stream skip operation.
851 * Returns: the size of the bytes skipped, or %-1 on error.
854 g_input_stream_skip_finish (GInputStream *stream,
855 GAsyncResult *result,
858 GInputStreamClass *class;
860 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), -1);
861 g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);
863 if (g_async_result_legacy_propagate_error (result, error))
865 else if (g_async_result_is_tagged (result, g_input_stream_skip_async))
866 return g_task_propagate_int (G_TASK (result), error);
868 class = G_INPUT_STREAM_GET_CLASS (stream);
869 return class->skip_finish (stream, result, error);
873 * g_input_stream_close_async:
874 * @stream: A #GInputStream.
875 * @io_priority: the [I/O priority][io-priority] of the request
876 * @cancellable: (allow-none): optional cancellable object
877 * @callback: (scope async): callback to call when the request is satisfied
878 * @user_data: (closure): the data to pass to callback function
880 * Requests an asynchronous closes of the stream, releasing resources related to it.
881 * When the operation is finished @callback will be called.
882 * You can then call g_input_stream_close_finish() to get the result of the
885 * For behaviour details see g_input_stream_close().
887 * The asyncronous methods have a default fallback that uses threads to implement
888 * asynchronicity, so they are optional for inheriting classes. However, if you
889 * override one you must override all.
892 g_input_stream_close_async (GInputStream *stream,
894 GCancellable *cancellable,
895 GAsyncReadyCallback callback,
898 GInputStreamClass *class;
899 GError *error = NULL;
901 g_return_if_fail (G_IS_INPUT_STREAM (stream));
903 if (stream->priv->closed)
907 task = g_task_new (stream, cancellable, callback, user_data);
908 g_task_set_source_tag (task, g_input_stream_close_async);
909 g_task_return_boolean (task, TRUE);
910 g_object_unref (task);
914 if (!g_input_stream_set_pending (stream, &error))
916 g_task_report_error (stream, callback, user_data,
917 g_input_stream_close_async,
922 class = G_INPUT_STREAM_GET_CLASS (stream);
923 stream->priv->outstanding_callback = callback;
924 g_object_ref (stream);
925 class->close_async (stream, io_priority, cancellable,
926 async_ready_close_callback_wrapper, user_data);
930 * g_input_stream_close_finish:
931 * @stream: a #GInputStream.
932 * @result: a #GAsyncResult.
933 * @error: a #GError location to store the error occurring, or %NULL to
936 * Finishes closing a stream asynchronously, started from g_input_stream_close_async().
938 * Returns: %TRUE if the stream was closed successfully.
941 g_input_stream_close_finish (GInputStream *stream,
942 GAsyncResult *result,
945 GInputStreamClass *class;
947 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);
948 g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE);
950 if (g_async_result_legacy_propagate_error (result, error))
952 else if (g_async_result_is_tagged (result, g_input_stream_close_async))
953 return g_task_propagate_boolean (G_TASK (result), error);
955 class = G_INPUT_STREAM_GET_CLASS (stream);
956 return class->close_finish (stream, result, error);
960 * g_input_stream_is_closed:
961 * @stream: input stream.
963 * Checks if an input stream is closed.
965 * Returns: %TRUE if the stream is closed.
968 g_input_stream_is_closed (GInputStream *stream)
970 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), TRUE);
972 return stream->priv->closed;
976 * g_input_stream_has_pending:
977 * @stream: input stream.
979 * Checks if an input stream has pending actions.
981 * Returns: %TRUE if @stream has pending actions.
984 g_input_stream_has_pending (GInputStream *stream)
986 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), TRUE);
988 return stream->priv->pending;
992 * g_input_stream_set_pending:
993 * @stream: input stream
994 * @error: a #GError location to store the error occurring, or %NULL to
997 * Sets @stream to have actions pending. If the pending flag is
998 * already set or @stream is closed, it will return %FALSE and set
1001 * Returns: %TRUE if pending was previously unset and is now set.
1004 g_input_stream_set_pending (GInputStream *stream, GError **error)
1006 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);
1008 if (stream->priv->closed)
1010 g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED,
1011 _("Stream is already closed"));
1015 if (stream->priv->pending)
1017 g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PENDING,
1018 /* Translators: This is an error you get if there is already an
1019 * operation running against this stream when you try to start
1021 _("Stream has outstanding operation"));
1025 stream->priv->pending = TRUE;
1030 * g_input_stream_clear_pending:
1031 * @stream: input stream
1033 * Clears the pending flag on @stream.
1036 g_input_stream_clear_pending (GInputStream *stream)
1038 g_return_if_fail (G_IS_INPUT_STREAM (stream));
1040 stream->priv->pending = FALSE;
1044 * g_input_stream_async_read_is_via_threads:
1045 * @stream: input stream
1047 * Checks if an input stream's read_async function uses threads.
1049 * Returns: %TRUE if @stream's read_async function uses threads.
1052 g_input_stream_async_read_is_via_threads (GInputStream *stream)
1054 GInputStreamClass *class;
1056 g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);
1058 class = G_INPUT_STREAM_GET_CLASS (stream);
1060 return (class->read_async == g_input_stream_real_read_async &&
1061 !(G_IS_POLLABLE_INPUT_STREAM (stream) &&
1062 g_pollable_input_stream_can_poll (G_POLLABLE_INPUT_STREAM (stream))));
1065 /********************************************
1066 * Default implementation of async ops *
1067 ********************************************/
1075 free_read_data (ReadData *op)
1077 g_slice_free (ReadData, op);
1081 read_async_thread (GTask *task,
1082 gpointer source_object,
1084 GCancellable *cancellable)
1086 GInputStream *stream = source_object;
1087 ReadData *op = task_data;
1088 GInputStreamClass *class;
1089 GError *error = NULL;
1092 class = G_INPUT_STREAM_GET_CLASS (stream);
1094 nread = class->read_fn (stream,
1095 op->buffer, op->count,
1096 g_task_get_cancellable (task),
1099 g_task_return_error (task, error);
1101 g_task_return_int (task, nread);
1104 static void read_async_pollable (GPollableInputStream *stream,
1108 read_async_pollable_ready (GPollableInputStream *stream,
1111 GTask *task = user_data;
1113 read_async_pollable (stream, task);
1118 read_async_pollable (GPollableInputStream *stream,
1121 ReadData *op = g_task_get_task_data (task);
1122 GError *error = NULL;
1125 if (g_task_return_error_if_cancelled (task))
1128 nread = G_POLLABLE_INPUT_STREAM_GET_INTERFACE (stream)->
1129 read_nonblocking (stream, op->buffer, op->count, &error);
1131 if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
1135 g_error_free (error);
1137 source = g_pollable_input_stream_create_source (stream,
1138 g_task_get_cancellable (task));
1139 g_task_attach_source (task, source,
1140 (GSourceFunc) read_async_pollable_ready);
1141 g_source_unref (source);
1146 g_task_return_error (task, error);
1148 g_task_return_int (task, nread);
1149 /* g_input_stream_real_read_async() unrefs task */
1154 g_input_stream_real_read_async (GInputStream *stream,
1158 GCancellable *cancellable,
1159 GAsyncReadyCallback callback,
1165 op = g_slice_new0 (ReadData);
1166 task = g_task_new (stream, cancellable, callback, user_data);
1167 g_task_set_task_data (task, op, (GDestroyNotify) free_read_data);
1168 g_task_set_priority (task, io_priority);
1169 op->buffer = buffer;
1172 if (!g_input_stream_async_read_is_via_threads (stream))
1173 read_async_pollable (G_POLLABLE_INPUT_STREAM (stream), task);
1175 g_task_run_in_thread (task, read_async_thread);
1176 g_object_unref (task);
1180 g_input_stream_real_read_finish (GInputStream *stream,
1181 GAsyncResult *result,
1184 g_return_val_if_fail (g_task_is_valid (result, stream), -1);
1186 return g_task_propagate_int (G_TASK (result), error);
1191 skip_async_thread (GTask *task,
1192 gpointer source_object,
1194 GCancellable *cancellable)
1196 GInputStream *stream = source_object;
1197 gsize count = GPOINTER_TO_SIZE (task_data);
1198 GInputStreamClass *class;
1199 GError *error = NULL;
1202 class = G_INPUT_STREAM_GET_CLASS (stream);
1203 ret = class->skip (stream, count,
1204 g_task_get_cancellable (task),
1207 g_task_return_error (task, error);
1209 g_task_return_int (task, ret);
1215 gsize count_skipped;
1216 } SkipFallbackAsyncData;
1219 skip_callback_wrapper (GObject *source_object,
1223 GInputStreamClass *class;
1224 GTask *task = user_data;
1225 SkipFallbackAsyncData *data = g_task_get_task_data (task);
1226 GError *error = NULL;
1229 ret = g_input_stream_read_finish (G_INPUT_STREAM (source_object), res, &error);
1234 data->count_skipped += ret;
1236 if (data->count > 0)
1238 class = G_INPUT_STREAM_GET_CLASS (source_object);
1239 class->read_async (G_INPUT_STREAM (source_object),
1240 data->buffer, MIN (8192, data->count),
1241 g_task_get_priority (task),
1242 g_task_get_cancellable (task),
1243 skip_callback_wrapper, task);
1249 g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED) &&
1250 data->count_skipped)
1252 /* No error, return partial read */
1253 g_clear_error (&error);
1257 g_task_return_error (task, error);
1259 g_task_return_int (task, data->count_skipped);
1260 g_object_unref (task);
1264 g_input_stream_real_skip_async (GInputStream *stream,
1267 GCancellable *cancellable,
1268 GAsyncReadyCallback callback,
1271 GInputStreamClass *class;
1272 SkipFallbackAsyncData *data;
1275 class = G_INPUT_STREAM_GET_CLASS (stream);
1277 task = g_task_new (stream, cancellable, callback, user_data);
1278 g_task_set_priority (task, io_priority);
1280 if (g_input_stream_async_read_is_via_threads (stream))
1282 /* Read is thread-using async fallback.
1283 * Make skip use threads too, so that we can use a possible sync skip
1284 * implementation. */
1285 g_task_set_task_data (task, GSIZE_TO_POINTER (count), NULL);
1287 g_task_run_in_thread (task, skip_async_thread);
1288 g_object_unref (task);
1292 /* TODO: Skip fallback uses too much memory, should do multiple read calls */
1294 /* There is a custom async read function, lets use that. */
1295 data = g_new (SkipFallbackAsyncData, 1);
1296 data->count = count;
1297 data->count_skipped = 0;
1298 g_task_set_task_data (task, data, g_free);
1299 g_task_set_check_cancellable (task, FALSE);
1300 class->read_async (stream, data->buffer, MIN (8192, count), io_priority, cancellable,
1301 skip_callback_wrapper, task);
1307 g_input_stream_real_skip_finish (GInputStream *stream,
1308 GAsyncResult *result,
1311 g_return_val_if_fail (g_task_is_valid (result, stream), -1);
1313 return g_task_propagate_int (G_TASK (result), error);
1317 close_async_thread (GTask *task,
1318 gpointer source_object,
1320 GCancellable *cancellable)
1322 GInputStream *stream = source_object;
1323 GInputStreamClass *class;
1324 GError *error = NULL;
1327 class = G_INPUT_STREAM_GET_CLASS (stream);
1328 if (class->close_fn)
1330 result = class->close_fn (stream,
1331 g_task_get_cancellable (task),
1335 g_task_return_error (task, error);
1340 g_task_return_boolean (task, TRUE);
1344 g_input_stream_real_close_async (GInputStream *stream,
1346 GCancellable *cancellable,
1347 GAsyncReadyCallback callback,
1352 task = g_task_new (stream, cancellable, callback, user_data);
1353 g_task_set_check_cancellable (task, FALSE);
1354 g_task_set_priority (task, io_priority);
1356 g_task_run_in_thread (task, close_async_thread);
1357 g_object_unref (task);
1361 g_input_stream_real_close_finish (GInputStream *stream,
1362 GAsyncResult *result,
1365 g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
1367 return g_task_propagate_boolean (G_TASK (result), error);