/* GIO - GLib Input, Output and Streaming Library * * Copyright (C) 2006-2007 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General * Public License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307, USA. * * Author: Alexander Larsson */ #include "config.h" #include "goutputstream.h" #include "gcancellable.h" #include "gasyncresult.h" #include "gsimpleasyncresult.h" #include "ginputstream.h" #include "gioerror.h" #include "glibintl.h" #include "gpollableoutputstream.h" /** * SECTION:goutputstream * @short_description: Base class for implementing streaming output * @include: gio/gio.h * * #GOutputStream has functions to write to a stream (g_output_stream_write()), * to close a stream (g_output_stream_close()) and to flush pending writes * (g_output_stream_flush()). * * To copy the content of an input stream to an output stream without * manually handling the reads and writes, use g_output_stream_splice(). * * All of these functions have async variants too. **/ G_DEFINE_ABSTRACT_TYPE (GOutputStream, g_output_stream, G_TYPE_OBJECT); struct _GOutputStreamPrivate { guint closed : 1; guint pending : 1; guint closing : 1; GAsyncReadyCallback outstanding_callback; }; static gssize g_output_stream_real_splice (GOutputStream *stream, GInputStream *source, GOutputStreamSpliceFlags flags, GCancellable *cancellable, GError **error); static void g_output_stream_real_write_async (GOutputStream *stream, const void *buffer, gsize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data); static gssize g_output_stream_real_write_finish (GOutputStream *stream, GAsyncResult *result, GError **error); static void g_output_stream_real_splice_async (GOutputStream *stream, GInputStream *source, GOutputStreamSpliceFlags flags, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data); static gssize g_output_stream_real_splice_finish (GOutputStream *stream, GAsyncResult *result, GError **error); static void g_output_stream_real_flush_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data); static gboolean g_output_stream_real_flush_finish (GOutputStream *stream, GAsyncResult *result, GError **error); static void g_output_stream_real_close_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer data); static gboolean g_output_stream_real_close_finish (GOutputStream *stream, GAsyncResult *result, GError **error); static gboolean _g_output_stream_close_internal (GOutputStream *stream, GCancellable *cancellable, GError **error); static void g_output_stream_finalize (GObject *object) { G_OBJECT_CLASS (g_output_stream_parent_class)->finalize (object); } static void g_output_stream_dispose (GObject *object) { GOutputStream *stream; stream = G_OUTPUT_STREAM (object); if (!stream->priv->closed) g_output_stream_close (stream, NULL, NULL); G_OBJECT_CLASS (g_output_stream_parent_class)->dispose (object); } static void g_output_stream_class_init (GOutputStreamClass *klass) { GObjectClass *gobject_class = G_OBJECT_CLASS (klass); g_type_class_add_private (klass, sizeof (GOutputStreamPrivate)); gobject_class->finalize = g_output_stream_finalize; gobject_class->dispose = g_output_stream_dispose; klass->splice = g_output_stream_real_splice; klass->write_async = g_output_stream_real_write_async; klass->write_finish = g_output_stream_real_write_finish; klass->splice_async = g_output_stream_real_splice_async; klass->splice_finish = g_output_stream_real_splice_finish; klass->flush_async = g_output_stream_real_flush_async; klass->flush_finish = g_output_stream_real_flush_finish; klass->close_async = g_output_stream_real_close_async; klass->close_finish = g_output_stream_real_close_finish; } static void g_output_stream_init (GOutputStream *stream) { stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream, G_TYPE_OUTPUT_STREAM, GOutputStreamPrivate); } /** * g_output_stream_write: * @stream: a #GOutputStream. * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write. * @count: the number of bytes to write * @cancellable: (allow-none): optional cancellable object * @error: location to store the error occurring, or %NULL to ignore * * Tries to write @count bytes from @buffer into the stream. Will block * during the operation. * * If count is 0, returns 0 and does nothing. A value of @count * larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error. * * On success, the number of bytes written to the stream is returned. * It is not an error if this is not the same as the requested size, as it * can happen e.g. on a partial I/O error, or if there is not enough * storage in the stream. All writes block until at least one byte * is written or an error occurs; 0 is never returned (unless * @count is 0). * * If @cancellable is not %NULL, then the operation can be cancelled by * triggering the cancellable object from another thread. If the operation * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. If an * operation was partially finished when the operation was cancelled the * partial result will be returned, without an error. * * On error -1 is returned and @error is set accordingly. * * Virtual: write_fn * * Return value: Number of bytes written, or -1 on error **/ gssize g_output_stream_write (GOutputStream *stream, const void *buffer, gsize count, GCancellable *cancellable, GError **error) { GOutputStreamClass *class; gssize res; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1); g_return_val_if_fail (buffer != NULL, 0); if (count == 0) return 0; if (((gssize) count) < 0) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT, _("Too large count value passed to %s"), G_STRFUNC); return -1; } class = G_OUTPUT_STREAM_GET_CLASS (stream); if (class->write_fn == NULL) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, _("Output stream doesn't implement write")); return -1; } if (!g_output_stream_set_pending (stream, error)) return -1; if (cancellable) g_cancellable_push_current (cancellable); res = class->write_fn (stream, buffer, count, cancellable, error); if (cancellable) g_cancellable_pop_current (cancellable); g_output_stream_clear_pending (stream); return res; } /** * g_output_stream_write_all: * @stream: a #GOutputStream. * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write. * @count: the number of bytes to write * @bytes_written: (out): location to store the number of bytes that was * written to the stream * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. * @error: location to store the error occurring, or %NULL to ignore * * Tries to write @count bytes from @buffer into the stream. Will block * during the operation. * * This function is similar to g_output_stream_write(), except it tries to * write as many bytes as requested, only stopping on an error. * * On a successful write of @count bytes, %TRUE is returned, and @bytes_written * is set to @count. * * If there is an error during the operation %FALSE is returned and @error * is set to indicate the error status, @bytes_written is updated to contain * the number of bytes written into the stream before the error occurred. * * Return value: %TRUE on success, %FALSE if there was an error **/ gboolean g_output_stream_write_all (GOutputStream *stream, const void *buffer, gsize count, gsize *bytes_written, GCancellable *cancellable, GError **error) { gsize _bytes_written; gssize res; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE); g_return_val_if_fail (buffer != NULL, FALSE); _bytes_written = 0; while (_bytes_written < count) { res = g_output_stream_write (stream, (char *)buffer + _bytes_written, count - _bytes_written, cancellable, error); if (res == -1) { if (bytes_written) *bytes_written = _bytes_written; return FALSE; } if (res == 0) g_warning ("Write returned zero without error"); _bytes_written += res; } if (bytes_written) *bytes_written = _bytes_written; return TRUE; } /** * g_output_stream_flush: * @stream: a #GOutputStream. * @cancellable: (allow-none): optional cancellable object * @error: location to store the error occurring, or %NULL to ignore * * Forces a write of all user-space buffered data for the given * @stream. Will block during the operation. Closing the stream will * implicitly cause a flush. * * This function is optional for inherited classes. * * If @cancellable is not %NULL, then the operation can be cancelled by * triggering the cancellable object from another thread. If the operation * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. * * Return value: %TRUE on success, %FALSE on error **/ gboolean g_output_stream_flush (GOutputStream *stream, GCancellable *cancellable, GError **error) { GOutputStreamClass *class; gboolean res; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE); if (!g_output_stream_set_pending (stream, error)) return FALSE; class = G_OUTPUT_STREAM_GET_CLASS (stream); res = TRUE; if (class->flush) { if (cancellable) g_cancellable_push_current (cancellable); res = class->flush (stream, cancellable, error); if (cancellable) g_cancellable_pop_current (cancellable); } g_output_stream_clear_pending (stream); return res; } /** * g_output_stream_splice: * @stream: a #GOutputStream. * @source: a #GInputStream. * @flags: a set of #GOutputStreamSpliceFlags. * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. * @error: a #GError location to store the error occurring, or %NULL to * ignore. * * Splices an input stream into an output stream. * * Returns: a #gssize containing the size of the data spliced, or * -1 if an error occurred. Note that if the number of bytes * spliced is greater than %G_MAXSSIZE, then that will be * returned, and there is no way to determine the actual number * of bytes spliced. **/ gssize g_output_stream_splice (GOutputStream *stream, GInputStream *source, GOutputStreamSpliceFlags flags, GCancellable *cancellable, GError **error) { GOutputStreamClass *class; gssize bytes_copied; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1); g_return_val_if_fail (G_IS_INPUT_STREAM (source), -1); if (g_input_stream_is_closed (source)) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED, _("Source stream is already closed")); return -1; } if (!g_output_stream_set_pending (stream, error)) return -1; class = G_OUTPUT_STREAM_GET_CLASS (stream); if (cancellable) g_cancellable_push_current (cancellable); bytes_copied = class->splice (stream, source, flags, cancellable, error); if (cancellable) g_cancellable_pop_current (cancellable); g_output_stream_clear_pending (stream); return bytes_copied; } static gssize g_output_stream_real_splice (GOutputStream *stream, GInputStream *source, GOutputStreamSpliceFlags flags, GCancellable *cancellable, GError **error) { GOutputStreamClass *class = G_OUTPUT_STREAM_GET_CLASS (stream); gssize n_read, n_written; gsize bytes_copied; char buffer[8192], *p; gboolean res; bytes_copied = 0; if (class->write_fn == NULL) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, _("Output stream doesn't implement write")); res = FALSE; goto notsupported; } res = TRUE; do { n_read = g_input_stream_read (source, buffer, sizeof (buffer), cancellable, error); if (n_read == -1) { res = FALSE; break; } if (n_read == 0) break; p = buffer; while (n_read > 0) { n_written = class->write_fn (stream, p, n_read, cancellable, error); if (n_written == -1) { res = FALSE; break; } p += n_written; n_read -= n_written; bytes_copied += n_written; } if (bytes_copied > G_MAXSSIZE) bytes_copied = G_MAXSSIZE; } while (res); notsupported: if (!res) error = NULL; /* Ignore further errors */ if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_SOURCE) { /* Don't care about errors in source here */ g_input_stream_close (source, cancellable, NULL); } if (flags & G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET) { /* But write errors on close are bad! */ res = _g_output_stream_close_internal (stream, cancellable, error); } if (res) return bytes_copied; return -1; } /* Must always be called inside * g_output_stream_set_pending()/g_output_stream_clear_pending(). */ static gboolean _g_output_stream_close_internal (GOutputStream *stream, GCancellable *cancellable, GError **error) { GOutputStreamClass *class; gboolean res; if (stream->priv->closed) return TRUE; class = G_OUTPUT_STREAM_GET_CLASS (stream); stream->priv->closing = TRUE; if (cancellable) g_cancellable_push_current (cancellable); if (class->flush) res = class->flush (stream, cancellable, error); else res = TRUE; if (!res) { /* flushing caused the error that we want to return, * but we still want to close the underlying stream if possible */ if (class->close_fn) class->close_fn (stream, cancellable, NULL); } else { res = TRUE; if (class->close_fn) res = class->close_fn (stream, cancellable, error); } if (cancellable) g_cancellable_pop_current (cancellable); stream->priv->closing = FALSE; stream->priv->closed = TRUE; return res; } /** * g_output_stream_close: * @stream: A #GOutputStream. * @cancellable: (allow-none): optional cancellable object * @error: location to store the error occurring, or %NULL to ignore * * Closes the stream, releasing resources related to it. * * Once the stream is closed, all other operations will return %G_IO_ERROR_CLOSED. * Closing a stream multiple times will not return an error. * * Closing a stream will automatically flush any outstanding buffers in the * stream. * * Streams will be automatically closed when the last reference * is dropped, but you might want to call this function to make sure * resources are released as early as possible. * * Some streams might keep the backing store of the stream (e.g. a file descriptor) * open after the stream is closed. See the documentation for the individual * stream for details. * * On failure the first error that happened will be reported, but the close * operation will finish as much as possible. A stream that failed to * close will still return %G_IO_ERROR_CLOSED for all operations. Still, it * is important to check and report the error to the user, otherwise * there might be a loss of data as all data might not be written. * * If @cancellable is not %NULL, then the operation can be cancelled by * triggering the cancellable object from another thread. If the operation * was cancelled, the error %G_IO_ERROR_CANCELLED will be returned. * Cancelling a close will still leave the stream closed, but there some streams * can use a faster close that doesn't block to e.g. check errors. On * cancellation (as with any error) there is no guarantee that all written * data will reach the target. * * Return value: %TRUE on success, %FALSE on failure **/ gboolean g_output_stream_close (GOutputStream *stream, GCancellable *cancellable, GError **error) { gboolean res; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE); if (stream->priv->closed) return TRUE; if (!g_output_stream_set_pending (stream, error)) return FALSE; res = _g_output_stream_close_internal (stream, cancellable, error); g_output_stream_clear_pending (stream); return res; } static void async_ready_callback_wrapper (GObject *source_object, GAsyncResult *res, gpointer user_data) { GOutputStream *stream = G_OUTPUT_STREAM (source_object); g_output_stream_clear_pending (stream); if (stream->priv->outstanding_callback) (*stream->priv->outstanding_callback) (source_object, res, user_data); g_object_unref (stream); } typedef struct { gint io_priority; GCancellable *cancellable; GError *flush_error; gpointer user_data; } CloseUserData; static void async_ready_close_callback_wrapper (GObject *source_object, GAsyncResult *res, gpointer user_data) { GOutputStream *stream = G_OUTPUT_STREAM (source_object); CloseUserData *data = user_data; stream->priv->closing = FALSE; stream->priv->closed = TRUE; g_output_stream_clear_pending (stream); if (stream->priv->outstanding_callback) { if (data->flush_error != NULL) { GSimpleAsyncResult *err; err = g_simple_async_result_new_take_error (source_object, stream->priv->outstanding_callback, data->user_data, data->flush_error); data->flush_error = NULL; (*stream->priv->outstanding_callback) (source_object, G_ASYNC_RESULT (err), data->user_data); g_object_unref (err); } else { (*stream->priv->outstanding_callback) (source_object, res, data->user_data); } } g_object_unref (stream); if (data->cancellable) g_object_unref (data->cancellable); if (data->flush_error) g_error_free (data->flush_error); g_slice_free (CloseUserData, data); } static void async_ready_close_flushed_callback_wrapper (GObject *source_object, GAsyncResult *res, gpointer user_data) { GOutputStream *stream = G_OUTPUT_STREAM (source_object); GOutputStreamClass *class; CloseUserData *data = user_data; GSimpleAsyncResult *simple; /* propagate the possible error */ if (G_IS_SIMPLE_ASYNC_RESULT (res)) { simple = G_SIMPLE_ASYNC_RESULT (res); g_simple_async_result_propagate_error (simple, &data->flush_error); } class = G_OUTPUT_STREAM_GET_CLASS (stream); /* we still close, even if there was a flush error */ class->close_async (stream, data->io_priority, data->cancellable, async_ready_close_callback_wrapper, user_data); } /** * g_output_stream_write_async: * @stream: A #GOutputStream. * @buffer: (array length=count) (element-type guint8): the buffer containing the data to write. * @count: the number of bytes to write * @io_priority: the io priority of the request. * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. * @callback: (scope async): callback to call when the request is satisfied * @user_data: (closure): the data to pass to callback function * * Request an asynchronous write of @count bytes from @buffer into * the stream. When the operation is finished @callback will be called. * You can then call g_output_stream_write_finish() to get the result of the * operation. * * During an async request no other sync and async calls are allowed, * and will result in %G_IO_ERROR_PENDING errors. * * A value of @count larger than %G_MAXSSIZE will cause a * %G_IO_ERROR_INVALID_ARGUMENT error. * * On success, the number of bytes written will be passed to the * @callback. It is not an error if this is not the same as the * requested size, as it can happen e.g. on a partial I/O error, * but generally we try to write as many bytes as requested. * * You are guaranteed that this method will never fail with * %G_IO_ERROR_WOULD_BLOCK - if @stream can't accept more data, the * method will just wait until this changes. * * Any outstanding I/O request with higher priority (lower numerical * value) will be executed before an outstanding request with lower * priority. Default priority is %G_PRIORITY_DEFAULT. * * The asyncronous methods have a default fallback that uses threads * to implement asynchronicity, so they are optional for inheriting * classes. However, if you override one you must override all. * * For the synchronous, blocking version of this function, see * g_output_stream_write(). **/ void g_output_stream_write_async (GOutputStream *stream, const void *buffer, gsize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GOutputStreamClass *class; GSimpleAsyncResult *simple; GError *error = NULL; g_return_if_fail (G_IS_OUTPUT_STREAM (stream)); g_return_if_fail (buffer != NULL); if (count == 0) { simple = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_write_async); g_simple_async_result_complete_in_idle (simple); g_object_unref (simple); return; } if (((gssize) count) < 0) { g_simple_async_report_error_in_idle (G_OBJECT (stream), callback, user_data, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT, _("Too large count value passed to %s"), G_STRFUNC); return; } if (!g_output_stream_set_pending (stream, &error)) { g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream), callback, user_data, error); return; } class = G_OUTPUT_STREAM_GET_CLASS (stream); stream->priv->outstanding_callback = callback; g_object_ref (stream); class->write_async (stream, buffer, count, io_priority, cancellable, async_ready_callback_wrapper, user_data); } /** * g_output_stream_write_finish: * @stream: a #GOutputStream. * @result: a #GAsyncResult. * @error: a #GError location to store the error occurring, or %NULL to * ignore. * * Finishes a stream write operation. * * Returns: a #gssize containing the number of bytes written to the stream. **/ gssize g_output_stream_write_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple; GOutputStreamClass *class; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1); g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1); if (G_IS_SIMPLE_ASYNC_RESULT (result)) { simple = G_SIMPLE_ASYNC_RESULT (result); if (g_simple_async_result_propagate_error (simple, error)) return -1; /* Special case writes of 0 bytes */ if (g_simple_async_result_get_source_tag (simple) == g_output_stream_write_async) return 0; } class = G_OUTPUT_STREAM_GET_CLASS (stream); return class->write_finish (stream, result, error); } typedef struct { GInputStream *source; gpointer user_data; GAsyncReadyCallback callback; } SpliceUserData; static void async_ready_splice_callback_wrapper (GObject *source_object, GAsyncResult *res, gpointer _data) { GOutputStream *stream = G_OUTPUT_STREAM (source_object); SpliceUserData *data = _data; g_output_stream_clear_pending (stream); if (data->callback) (*data->callback) (source_object, res, data->user_data); g_object_unref (stream); g_object_unref (data->source); g_free (data); } /** * g_output_stream_splice_async: * @stream: a #GOutputStream. * @source: a #GInputStream. * @flags: a set of #GOutputStreamSpliceFlags. * @io_priority: the io priority of the request. * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. * @callback: (scope async): a #GAsyncReadyCallback. * @user_data: (closure): user data passed to @callback. * * Splices a stream asynchronously. * When the operation is finished @callback will be called. * You can then call g_output_stream_splice_finish() to get the * result of the operation. * * For the synchronous, blocking version of this function, see * g_output_stream_splice(). **/ void g_output_stream_splice_async (GOutputStream *stream, GInputStream *source, GOutputStreamSpliceFlags flags, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GOutputStreamClass *class; SpliceUserData *data; GError *error = NULL; g_return_if_fail (G_IS_OUTPUT_STREAM (stream)); g_return_if_fail (G_IS_INPUT_STREAM (source)); if (g_input_stream_is_closed (source)) { g_simple_async_report_error_in_idle (G_OBJECT (stream), callback, user_data, G_IO_ERROR, G_IO_ERROR_CLOSED, _("Source stream is already closed")); return; } if (!g_output_stream_set_pending (stream, &error)) { g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream), callback, user_data, error); return; } class = G_OUTPUT_STREAM_GET_CLASS (stream); data = g_new0 (SpliceUserData, 1); data->callback = callback; data->user_data = user_data; data->source = g_object_ref (source); g_object_ref (stream); class->splice_async (stream, source, flags, io_priority, cancellable, async_ready_splice_callback_wrapper, data); } /** * g_output_stream_splice_finish: * @stream: a #GOutputStream. * @result: a #GAsyncResult. * @error: a #GError location to store the error occurring, or %NULL to * ignore. * * Finishes an asynchronous stream splice operation. * * Returns: a #gssize of the number of bytes spliced. Note that if the * number of bytes spliced is greater than %G_MAXSSIZE, then that * will be returned, and there is no way to determine the actual * number of bytes spliced. **/ gssize g_output_stream_splice_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple; GOutputStreamClass *class; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), -1); g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1); if (G_IS_SIMPLE_ASYNC_RESULT (result)) { simple = G_SIMPLE_ASYNC_RESULT (result); if (g_simple_async_result_propagate_error (simple, error)) return -1; } class = G_OUTPUT_STREAM_GET_CLASS (stream); return class->splice_finish (stream, result, error); } /** * g_output_stream_flush_async: * @stream: a #GOutputStream. * @io_priority: the io priority of the request. * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore. * @callback: (scope async): a #GAsyncReadyCallback to call when the request is satisfied * @user_data: (closure): the data to pass to callback function * * Forces an asynchronous write of all user-space buffered data for * the given @stream. * For behaviour details see g_output_stream_flush(). * * When the operation is finished @callback will be * called. You can then call g_output_stream_flush_finish() to get the * result of the operation. **/ void g_output_stream_flush_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GOutputStreamClass *class; GSimpleAsyncResult *simple; GError *error = NULL; g_return_if_fail (G_IS_OUTPUT_STREAM (stream)); if (!g_output_stream_set_pending (stream, &error)) { g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream), callback, user_data, error); return; } stream->priv->outstanding_callback = callback; g_object_ref (stream); class = G_OUTPUT_STREAM_GET_CLASS (stream); if (class->flush_async == NULL) { simple = g_simple_async_result_new (G_OBJECT (stream), async_ready_callback_wrapper, user_data, g_output_stream_flush_async); g_simple_async_result_complete_in_idle (simple); g_object_unref (simple); return; } class->flush_async (stream, io_priority, cancellable, async_ready_callback_wrapper, user_data); } /** * g_output_stream_flush_finish: * @stream: a #GOutputStream. * @result: a GAsyncResult. * @error: a #GError location to store the error occurring, or %NULL to * ignore. * * Finishes flushing an output stream. * * Returns: %TRUE if flush operation succeeded, %FALSE otherwise. **/ gboolean g_output_stream_flush_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple; GOutputStreamClass *klass; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE); g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE); if (G_IS_SIMPLE_ASYNC_RESULT (result)) { simple = G_SIMPLE_ASYNC_RESULT (result); if (g_simple_async_result_propagate_error (simple, error)) return FALSE; /* Special case default implementation */ if (g_simple_async_result_get_source_tag (simple) == g_output_stream_flush_async) return TRUE; } klass = G_OUTPUT_STREAM_GET_CLASS (stream); return klass->flush_finish (stream, result, error); } /** * g_output_stream_close_async: * @stream: A #GOutputStream. * @io_priority: the io priority of the request. * @cancellable: (allow-none): optional cancellable object * @callback: (scope async): callback to call when the request is satisfied * @user_data: (closure): the data to pass to callback function * * Requests an asynchronous close of the stream, releasing resources * related to it. When the operation is finished @callback will be * called. You can then call g_output_stream_close_finish() to get * the result of the operation. * * For behaviour details see g_output_stream_close(). * * The asyncronous methods have a default fallback that uses threads * to implement asynchronicity, so they are optional for inheriting * classes. However, if you override one you must override all. **/ void g_output_stream_close_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GOutputStreamClass *class; GSimpleAsyncResult *simple; GError *error = NULL; CloseUserData *data; g_return_if_fail (G_IS_OUTPUT_STREAM (stream)); if (stream->priv->closed) { simple = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_close_async); g_simple_async_result_complete_in_idle (simple); g_object_unref (simple); return; } if (!g_output_stream_set_pending (stream, &error)) { g_simple_async_report_take_gerror_in_idle (G_OBJECT (stream), callback, user_data, error); return; } class = G_OUTPUT_STREAM_GET_CLASS (stream); stream->priv->closing = TRUE; stream->priv->outstanding_callback = callback; g_object_ref (stream); data = g_slice_new0 (CloseUserData); if (cancellable != NULL) data->cancellable = g_object_ref (cancellable); data->io_priority = io_priority; data->user_data = user_data; /* Call close_async directly if there is no need to flush, or if the flush can be done sync (in the output stream async close thread) */ if (class->flush_async == NULL || (class->flush_async == g_output_stream_real_flush_async && (class->flush == NULL || class->close_async == g_output_stream_real_close_async))) { class->close_async (stream, io_priority, cancellable, async_ready_close_callback_wrapper, data); } else { /* First do an async flush, then do the async close in the callback wrapper (see async_ready_close_flushed_callback_wrapper) */ class->flush_async (stream, io_priority, cancellable, async_ready_close_flushed_callback_wrapper, data); } } /** * g_output_stream_close_finish: * @stream: a #GOutputStream. * @result: a #GAsyncResult. * @error: a #GError location to store the error occurring, or %NULL to * ignore. * * Closes an output stream. * * Returns: %TRUE if stream was successfully closed, %FALSE otherwise. **/ gboolean g_output_stream_close_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple; GOutputStreamClass *class; g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE); g_return_val_if_fail (G_IS_ASYNC_RESULT (result), FALSE); if (G_IS_SIMPLE_ASYNC_RESULT (result)) { simple = G_SIMPLE_ASYNC_RESULT (result); if (g_simple_async_result_propagate_error (simple, error)) return FALSE; /* Special case already closed */ if (g_simple_async_result_get_source_tag (simple) == g_output_stream_close_async) return TRUE; } class = G_OUTPUT_STREAM_GET_CLASS (stream); return class->close_finish (stream, result, error); } /** * g_output_stream_is_closed: * @stream: a #GOutputStream. * * Checks if an output stream has already been closed. * * Returns: %TRUE if @stream is closed. %FALSE otherwise. **/ gboolean g_output_stream_is_closed (GOutputStream *stream) { g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE); return stream->priv->closed; } /** * g_output_stream_is_closing: * @stream: a #GOutputStream. * * Checks if an output stream is being closed. This can be * used inside e.g. a flush implementation to see if the * flush (or other i/o operation) is called from within * the closing operation. * * Returns: %TRUE if @stream is being closed. %FALSE otherwise. * * Since: 2.24 **/ gboolean g_output_stream_is_closing (GOutputStream *stream) { g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), TRUE); return stream->priv->closing; } /** * g_output_stream_has_pending: * @stream: a #GOutputStream. * * Checks if an ouput stream has pending actions. * * Returns: %TRUE if @stream has pending actions. **/ gboolean g_output_stream_has_pending (GOutputStream *stream) { g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE); return stream->priv->pending; } /** * g_output_stream_set_pending: * @stream: a #GOutputStream. * @error: a #GError location to store the error occurring, or %NULL to * ignore. * * Sets @stream to have actions pending. If the pending flag is * already set or @stream is closed, it will return %FALSE and set * @error. * * Return value: %TRUE if pending was previously unset and is now set. **/ gboolean g_output_stream_set_pending (GOutputStream *stream, GError **error) { g_return_val_if_fail (G_IS_OUTPUT_STREAM (stream), FALSE); if (stream->priv->closed) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED, _("Stream is already closed")); return FALSE; } if (stream->priv->pending) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_PENDING, /* Translators: This is an error you get if there is * already an operation running against this stream when * you try to start one */ _("Stream has outstanding operation")); return FALSE; } stream->priv->pending = TRUE; return TRUE; } /** * g_output_stream_clear_pending: * @stream: output stream * * Clears the pending flag on @stream. **/ void g_output_stream_clear_pending (GOutputStream *stream) { g_return_if_fail (G_IS_OUTPUT_STREAM (stream)); stream->priv->pending = FALSE; } /******************************************** * Default implementation of async ops * ********************************************/ typedef struct { const void *buffer; gsize count_requested; gssize count_written; GCancellable *cancellable; gint io_priority; gboolean need_idle; } WriteData; static void write_async_thread (GSimpleAsyncResult *res, GObject *object, GCancellable *cancellable) { WriteData *op; GOutputStreamClass *class; GError *error = NULL; class = G_OUTPUT_STREAM_GET_CLASS (object); op = g_simple_async_result_get_op_res_gpointer (res); op->count_written = class->write_fn (G_OUTPUT_STREAM (object), op->buffer, op->count_requested, cancellable, &error); if (op->count_written == -1) g_simple_async_result_take_error (res, error); } static void write_async_pollable (GPollableOutputStream *stream, GSimpleAsyncResult *result); static gboolean write_async_pollable_ready (GPollableOutputStream *stream, gpointer user_data) { GSimpleAsyncResult *result = user_data; write_async_pollable (stream, result); return FALSE; } static void write_async_pollable (GPollableOutputStream *stream, GSimpleAsyncResult *result) { GError *error = NULL; WriteData *op = g_simple_async_result_get_op_res_gpointer (result); if (g_cancellable_set_error_if_cancelled (op->cancellable, &error)) op->count_written = -1; else { op->count_written = G_POLLABLE_OUTPUT_STREAM_GET_INTERFACE (stream)-> write_nonblocking (stream, op->buffer, op->count_requested, &error); } if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK)) { GSource *source; g_error_free (error); op->need_idle = FALSE; source = g_pollable_output_stream_create_source (stream, op->cancellable); g_source_set_callback (source, (GSourceFunc) write_async_pollable_ready, g_object_ref (result), g_object_unref); g_source_set_priority (source, op->io_priority); g_source_attach (source, g_main_context_get_thread_default ()); g_source_unref (source); return; } if (op->count_written == -1) g_simple_async_result_take_error (result, error); if (op->need_idle) g_simple_async_result_complete_in_idle (result); else g_simple_async_result_complete (result); } static void g_output_stream_real_write_async (GOutputStream *stream, const void *buffer, gsize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GSimpleAsyncResult *res; WriteData *op; op = g_new0 (WriteData, 1); res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async); g_simple_async_result_set_op_res_gpointer (res, op, g_free); op->buffer = buffer; op->count_requested = count; if (G_IS_POLLABLE_OUTPUT_STREAM (stream) && g_pollable_output_stream_can_poll (G_POLLABLE_OUTPUT_STREAM (stream))) write_async_pollable (G_POLLABLE_OUTPUT_STREAM (stream), res); else g_simple_async_result_run_in_thread (res, write_async_thread, io_priority, cancellable); g_object_unref (res); } static gssize g_output_stream_real_write_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result); WriteData *op; g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_write_async); op = g_simple_async_result_get_op_res_gpointer (simple); return op->count_written; } typedef struct { GInputStream *source; GOutputStreamSpliceFlags flags; gssize bytes_copied; } SpliceData; static void splice_async_thread (GSimpleAsyncResult *result, GObject *object, GCancellable *cancellable) { SpliceData *op; GOutputStreamClass *class; GError *error = NULL; GOutputStream *stream; stream = G_OUTPUT_STREAM (object); class = G_OUTPUT_STREAM_GET_CLASS (object); op = g_simple_async_result_get_op_res_gpointer (result); op->bytes_copied = class->splice (stream, op->source, op->flags, cancellable, &error); if (op->bytes_copied == -1) g_simple_async_result_take_error (result, error); } static void g_output_stream_real_splice_async (GOutputStream *stream, GInputStream *source, GOutputStreamSpliceFlags flags, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GSimpleAsyncResult *res; SpliceData *op; op = g_new0 (SpliceData, 1); res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_splice_async); g_simple_async_result_set_op_res_gpointer (res, op, g_free); op->flags = flags; op->source = source; /* TODO: In the case where both source and destintion have non-threadbased async calls we can use a true async copy here */ g_simple_async_result_run_in_thread (res, splice_async_thread, io_priority, cancellable); g_object_unref (res); } static gssize g_output_stream_real_splice_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result); SpliceData *op; g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_splice_async); op = g_simple_async_result_get_op_res_gpointer (simple); return op->bytes_copied; } static void flush_async_thread (GSimpleAsyncResult *res, GObject *object, GCancellable *cancellable) { GOutputStreamClass *class; gboolean result; GError *error = NULL; class = G_OUTPUT_STREAM_GET_CLASS (object); result = TRUE; if (class->flush) result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error); if (!result) g_simple_async_result_take_error (res, error); } static void g_output_stream_real_flush_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GSimpleAsyncResult *res; res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_write_async); g_simple_async_result_run_in_thread (res, flush_async_thread, io_priority, cancellable); g_object_unref (res); } static gboolean g_output_stream_real_flush_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { return TRUE; } static void close_async_thread (GSimpleAsyncResult *res, GObject *object, GCancellable *cancellable) { GOutputStreamClass *class; GError *error = NULL; gboolean result = TRUE; class = G_OUTPUT_STREAM_GET_CLASS (object); /* Do a flush here if there is a flush function, and we did not have to do an async flush before (see g_output_stream_close_async) */ if (class->flush != NULL && (class->flush_async == NULL || class->flush_async == g_output_stream_real_flush_async)) { result = class->flush (G_OUTPUT_STREAM (object), cancellable, &error); } /* Auto handling of cancelation disabled, and ignore cancellation, since we want to close things anyway, although possibly in a quick-n-dirty way. At least we never want to leak open handles */ if (class->close_fn) { /* Make sure to close, even if the flush failed (see sync close) */ if (!result) class->close_fn (G_OUTPUT_STREAM (object), cancellable, NULL); else result = class->close_fn (G_OUTPUT_STREAM (object), cancellable, &error); if (!result) g_simple_async_result_take_error (res, error); } } static void g_output_stream_real_close_async (GOutputStream *stream, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GSimpleAsyncResult *res; res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_output_stream_real_close_async); g_simple_async_result_set_handle_cancellation (res, FALSE); g_simple_async_result_run_in_thread (res, close_async_thread, io_priority, cancellable); g_object_unref (res); } static gboolean g_output_stream_real_close_finish (GOutputStream *stream, GAsyncResult *result, GError **error) { GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result); g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_output_stream_real_close_async); return TRUE; }