/* 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 2.1 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, see <http://www.gnu.org/licenses/>.

 *

 * Author: Alexander Larsson <alexl@redhat.com>

 */

#include "config.h"

#include <glib.h>

#include "glibintl.h"

#include "ginputstream.h"

#include "gioprivate.h"

#include "gseekable.h"

#include "gcancellable.h"

#include "gasyncresult.h"

#include "gioerror.h"

#include "gpollableinputstream.h"

/**

 * SECTION:ginputstream

 * @short_description: Base class for implementing streaming input

 * @include: gio/gio.h

 *

 * #GInputStream has functions to read from a stream (g_input_stream_read()),

 * to close a stream (g_input_stream_close()) and to skip some content

 * (g_input_stream_skip()). 

 *

 * To copy the content of an input stream to an output stream without 

 * manually handling the reads and writes, use g_output_stream_splice().

 *

 * See the documentation for #GIOStream for details of thread safety of

 * streaming APIs.

 *

 * All of these functions have async variants too.

 **/

struct _GInputStreamPrivate {

  guint closed : 1;

  guint pending : 1;

  GAsyncReadyCallback outstanding_callback;

};

G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GInputStream, g_input_stream, G_TYPE_OBJECT)

static gssize   g_input_stream_real_skip         (GInputStream         *stream,

						  gsize                 count,

						  GCancellable         *cancellable,

						  GError              **error);

static void     g_input_stream_real_read_async   (GInputStream         *stream,

						  void                 *buffer,

						  gsize                 count,

						  int                   io_priority,

						  GCancellable         *cancellable,

						  GAsyncReadyCallback   callback,

						  gpointer              user_data);

static gssize   g_input_stream_real_read_finish  (GInputStream         *stream,

						  GAsyncResult         *result,

						  GError              **error);

static void     g_input_stream_real_skip_async   (GInputStream         *stream,

						  gsize                 count,

						  int                   io_priority,

						  GCancellable         *cancellable,

						  GAsyncReadyCallback   callback,

						  gpointer              data);

static gssize   g_input_stream_real_skip_finish  (GInputStream         *stream,

						  GAsyncResult         *result,

						  GError              **error);

static void     g_input_stream_real_close_async  (GInputStream         *stream,

						  int                   io_priority,

						  GCancellable         *cancellable,

						  GAsyncReadyCallback   callback,

						  gpointer              data);

static gboolean g_input_stream_real_close_finish (GInputStream         *stream,

						  GAsyncResult         *result,

						  GError              **error);

static void

g_input_stream_dispose (GObject *object)

{

  GInputStream *stream;

  stream = G_INPUT_STREAM (object);

  if (!stream->priv->closed)

    g_input_stream_close (stream, NULL, NULL);

  G_OBJECT_CLASS (g_input_stream_parent_class)->dispose (object);

}

static void

g_input_stream_class_init (GInputStreamClass *klass)

{

  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);

  gobject_class->dispose = g_input_stream_dispose;

  klass->skip = g_input_stream_real_skip;

  klass->read_async = g_input_stream_real_read_async;

  klass->read_finish = g_input_stream_real_read_finish;

  klass->skip_async = g_input_stream_real_skip_async;

  klass->skip_finish = g_input_stream_real_skip_finish;

  klass->close_async = g_input_stream_real_close_async;

  klass->close_finish = g_input_stream_real_close_finish;

}

static void

g_input_stream_init (GInputStream *stream)

{

  stream->priv = g_input_stream_get_instance_private (stream);

}

/**

 * g_input_stream_read:

 * @stream: a #GInputStream.

 * @buffer: (array length=count) (element-type guint8): a buffer to

 *     read data into (which should be at least count bytes long).

 * @count: the number of bytes that will be read from the stream

 * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.

 * @error: location to store the error occurring, or %NULL to ignore

 *

 * Tries to read @count bytes from the stream into the buffer starting at

 * @buffer. Will block during this read.

 * 

 * If count is zero returns zero 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 read into the buffer is returned.

 * It is not an error if this is not the same as the requested size, as it

 * can happen e.g. near the end of a file. Zero is returned on end of file

 * (or if @count is zero),  but never otherwise.

 *

 * The returned @buffer is not a nul-terminated string, it can contain nul bytes

 * at any position, and this function doesn't nul-terminate the @buffer.

 *

 * 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.

 * 

 * Returns: Number of bytes read, or -1 on error, or 0 on end of file.

 **/

gssize

g_input_stream_read  (GInputStream  *stream,

		      void          *buffer,

		      gsize          count,

		      GCancellable  *cancellable,

		      GError       **error)

{

  GInputStreamClass *class;

  gssize res;

  g_return_val_if_fail (G_IS_INPUT_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_INPUT_STREAM_GET_CLASS (stream);

  if (class->read_fn == NULL) 

    {

      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,

                           _("Input stream doesn’t implement read"));

      return -1;

    }

  if (!g_input_stream_set_pending (stream, error))

    return -1;

  if (cancellable)

    g_cancellable_push_current (cancellable);

  res = class->read_fn (stream, buffer, count, cancellable, error);

  if (cancellable)

    g_cancellable_pop_current (cancellable);

  g_input_stream_clear_pending (stream);

  return res;

}

/**

 * g_input_stream_read_all:

 * @stream: a #GInputStream.

 * @buffer: (array length=count) (element-type guint8): a buffer to

 *     read data into (which should be at least count bytes long).

 * @count: the number of bytes that will be read from the stream

 * @bytes_read: (out): location to store the number of bytes that was read from the stream

 * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.

 * @error: location to store the error occurring, or %NULL to ignore

 *

 * Tries to read @count bytes from the stream into the buffer starting at

 * @buffer. Will block during this read.

 *

 * This function is similar to g_input_stream_read(), except it tries to

 * read as many bytes as requested, only stopping on an error or end of stream.

 *

 * On a successful read of @count bytes, or if we reached the end of the

 * stream,  %TRUE is returned, and @bytes_read is set to the number of bytes

 * read into @buffer.

 * 

 * If there is an error during the operation %FALSE is returned and @error

 * is set to indicate the error status.

 *

 * As a special exception to the normal conventions for functions that

 * use #GError, if this function returns %FALSE (and sets @error) then

 * @bytes_read will be set to the number of bytes that were successfully

 * read before the error was encountered.  This functionality is only

 * available from C.  If you need it from another language then you must

 * write your own loop around g_input_stream_read().

 *

 * Returns: %TRUE on success, %FALSE if there was an error

 **/

gboolean

g_input_stream_read_all (GInputStream  *stream,

			 void          *buffer,

			 gsize          count,

			 gsize         *bytes_read,

			 GCancellable  *cancellable,

			 GError       **error)

{

  gsize _bytes_read;

  gssize res;

  g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);

  g_return_val_if_fail (buffer != NULL, FALSE);

  _bytes_read = 0;

  while (_bytes_read < count)

    {

      res = g_input_stream_read (stream, (char *)buffer + _bytes_read, count - _bytes_read,

				 cancellable, error);

      if (res == -1)

	{

	  if (bytes_read)

	    *bytes_read = _bytes_read;

	  return FALSE;

	}

      if (res == 0)

	break;

      _bytes_read += res;

    }

  if (bytes_read)

    *bytes_read = _bytes_read;

  return TRUE;

}

/**

 * g_input_stream_read_bytes:

 * @stream: a #GInputStream.

 * @count: maximum number of bytes that will be read from the stream. Common

 * values include 4096 and 8192.

 * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.

 * @error: location to store the error occurring, or %NULL to ignore

 *

 * Like g_input_stream_read(), this tries to read @count bytes from

 * the stream in a blocking fashion. However, rather than reading into

 * a user-supplied buffer, this will create a new #GBytes containing

 * the data that was read. This may be easier to use from language

 * bindings.

 *

 * If count is zero, returns a zero-length #GBytes and does nothing. A

 * value of @count larger than %G_MAXSSIZE will cause a

 * %G_IO_ERROR_INVALID_ARGUMENT error.

 *

 * On success, a new #GBytes is returned. It is not an error if the

 * size of this object is not the same as the requested size, as it

 * can happen e.g. near the end of a file. A zero-length #GBytes is

 * returned on end of file (or if @count is zero), but never

 * otherwise.

 *

 * 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 %NULL is returned and @error is set accordingly.

 *

 * Returns: (transfer full): a new #GBytes, or %NULL on error

 *

 * Since: 2.34

 **/

GBytes *

g_input_stream_read_bytes (GInputStream  *stream,

			   gsize          count,

			   GCancellable  *cancellable,

			   GError       **error)

{

  guchar *buf;

  gssize nread;

  buf = g_malloc (count);

  nread = g_input_stream_read (stream, buf, count, cancellable, error);

  if (nread == -1)

    {

      g_free (buf);

      return NULL;

    }

  else if (nread == 0)

    {

      g_free (buf);

      return g_bytes_new_static ("", 0);

    }

  else

    return g_bytes_new_take (buf, nread);

}

/**

 * g_input_stream_skip:

 * @stream: a #GInputStream.

 * @count: the number of bytes that will be skipped from the stream

 * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore. 

 * @error: location to store the error occurring, or %NULL to ignore

 *

 * Tries to skip @count bytes from the stream. Will block during the operation.

 *

 * This is identical to g_input_stream_read(), from a behaviour standpoint,

 * but the bytes that are skipped are not returned to the user. Some

 * streams have an implementation that is more efficient than reading the data.

 *

 * This function is optional for inherited classes, as the default implementation

 * emulates it using read.

 *

 * 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.

 *

 * Returns: Number of bytes skipped, or -1 on error

 **/

gssize

g_input_stream_skip (GInputStream  *stream,

		     gsize          count,

		     GCancellable  *cancellable,

		     GError       **error)

{

  GInputStreamClass *class;

  gssize res;

  g_return_val_if_fail (G_IS_INPUT_STREAM (stream), -1);

  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_INPUT_STREAM_GET_CLASS (stream);

  if (!g_input_stream_set_pending (stream, error))

    return -1;

  if (cancellable)

    g_cancellable_push_current (cancellable);

  res = class->skip (stream, count, cancellable, error);

  if (cancellable)

    g_cancellable_pop_current (cancellable);

  g_input_stream_clear_pending (stream);

  return res;

}

static gssize

g_input_stream_real_skip (GInputStream  *stream,

			  gsize          count,

			  GCancellable  *cancellable,

			  GError       **error)

{

  GInputStreamClass *class;

  gssize ret, read_bytes;

  char buffer[8192];

  GError *my_error;

  if (G_IS_SEEKABLE (stream) && g_seekable_can_seek (G_SEEKABLE (stream)))

    {

      if (g_seekable_seek (G_SEEKABLE (stream),

			   count,

			   G_SEEK_CUR,

			   cancellable,

			   NULL))

	return count;

    }

  /* If not seekable, or seek failed, fall back to reading data: */

  class = G_INPUT_STREAM_GET_CLASS (stream);

  read_bytes = 0;

  while (1)

    {

      my_error = NULL;

      ret = class->read_fn (stream, buffer, MIN (sizeof (buffer), count),

                            cancellable, &my_error);

      if (ret == -1)

	{

	  if (read_bytes > 0 &&

	      my_error->domain == G_IO_ERROR &&

	      my_error->code == G_IO_ERROR_CANCELLED)

	    {

	      g_error_free (my_error);

	      return read_bytes;

	    }

	  g_propagate_error (error, my_error);

	  return -1;

	}

      count -= ret;

      read_bytes += ret;

      if (ret == 0 || count == 0)

        return read_bytes;

    }

}

/**

 * g_input_stream_close:

 * @stream: A #GInputStream.

 * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.

 * @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.

 *

 * 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.

 *

 * 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 some streams

 * can use a faster close that doesn't block to e.g. check errors. 

 *

 * Returns: %TRUE on success, %FALSE on failure

 **/

gboolean

g_input_stream_close (GInputStream  *stream,

		      GCancellable  *cancellable,

		      GError       **error)

{

  GInputStreamClass *class;

  gboolean res;

  g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);

  class = G_INPUT_STREAM_GET_CLASS (stream);

  if (stream->priv->closed)

    return TRUE;

  res = TRUE;

  if (!g_input_stream_set_pending (stream, error))

    return FALSE;

  if (cancellable)

    g_cancellable_push_current (cancellable);

  if (class->close_fn)

    res = class->close_fn (stream, cancellable, error);

  if (cancellable)

    g_cancellable_pop_current (cancellable);

  g_input_stream_clear_pending (stream);

  stream->priv->closed = TRUE;

  return res;

}

static void

async_ready_callback_wrapper (GObject      *source_object,

			      GAsyncResult *res,

			      gpointer      user_data)

{

  GInputStream *stream = G_INPUT_STREAM (source_object);

  g_input_stream_clear_pending (stream);

  if (stream->priv->outstanding_callback)

    (*stream->priv->outstanding_callback) (source_object, res, user_data);

  g_object_unref (stream);

}

static void

async_ready_close_callback_wrapper (GObject      *source_object,

				    GAsyncResult *res,

				    gpointer      user_data)

{

  GInputStream *stream = G_INPUT_STREAM (source_object);

  g_input_stream_clear_pending (stream);

  stream->priv->closed = TRUE;

  if (stream->priv->outstanding_callback)

    (*stream->priv->outstanding_callback) (source_object, res, user_data);

  g_object_unref (stream);

}

/**

 * g_input_stream_read_async:

 * @stream: A #GInputStream.

 * @buffer: (array length=count) (element-type guint8): a buffer to

 *     read data into (which should be at least count bytes long).

 * @count: the number of bytes that will be read from the stream

 * @io_priority: the [I/O priority][io-priority]

 * of the request. 

 * @cancellable: (nullable): 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 read of @count bytes from the stream into the buffer

 * starting at @buffer. When the operation is finished @callback will be called. 

 * You can then call g_input_stream_read_finish() to get the result of the 

 * operation.

 *

 * During an async request no other sync and async calls are allowed on @stream, 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 read into the buffer 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. near the end of a file, but generally we try to read

 * as many bytes as requested. Zero is returned on end of file

 * (or if @count is zero),  but never otherwise.

 *

 * 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 asynchronous 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_input_stream_read_async (GInputStream        *stream,

			   void                *buffer,

			   gsize                count,

			   int                  io_priority,

			   GCancellable        *cancellable,

			   GAsyncReadyCallback  callback,

			   gpointer             user_data)

{

  GInputStreamClass *class;

  GError *error = NULL;

  g_return_if_fail (G_IS_INPUT_STREAM (stream));

  g_return_if_fail (buffer != NULL);

  if (count == 0)

    {

      GTask *task;

      task = g_task_new (stream, cancellable, callback, user_data);

      g_task_set_source_tag (task, g_input_stream_read_async);

      g_task_return_int (task, 0);

      g_object_unref (task);

      return;

    }

  if (((gssize) count) < 0)

    {

      g_task_report_new_error (stream, callback, user_data,

                               g_input_stream_read_async,

                               G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,

                               _("Too large count value passed to %s"),

                               G_STRFUNC);

      return;

    }

  if (!g_input_stream_set_pending (stream, &error))

    {

      g_task_report_error (stream, callback, user_data,

                           g_input_stream_read_async,

                           error);

      return;

    }

  class = G_INPUT_STREAM_GET_CLASS (stream);

  stream->priv->outstanding_callback = callback;

  g_object_ref (stream);

  class->read_async (stream, buffer, count, io_priority, cancellable,

		     async_ready_callback_wrapper, user_data);

}

/**

 * g_input_stream_read_finish:

 * @stream: a #GInputStream.

 * @result: a #GAsyncResult.

 * @error: a #GError location to store the error occurring, or %NULL to 

 * ignore.

 * 

 * Finishes an asynchronous stream read operation. 

 * 

 * Returns: number of bytes read in, or -1 on error, or 0 on end of file.

 **/

gssize

g_input_stream_read_finish (GInputStream  *stream,

			    GAsyncResult  *result,

			    GError       **error)

{

  GInputStreamClass *class;

  g_return_val_if_fail (G_IS_INPUT_STREAM (stream), -1);

  g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1);

  if (g_async_result_legacy_propagate_error (result, error))

    return -1;

  else if (g_async_result_is_tagged (result, g_input_stream_read_async))

    return g_task_propagate_int (G_TASK (result), error);

  class = G_INPUT_STREAM_GET_CLASS (stream);

  return class->read_finish (stream, result, error);

}

typedef struct

{

  gchar *buffer;

  gsize to_read;

  gsize bytes_read;

} AsyncReadAll;

static void

free_async_read_all (gpointer data)

{

  g_slice_free (AsyncReadAll, data);

}

static void

read_all_callback (GObject      *stream,

                   GAsyncResult *result,

                   gpointer      user_data)

{

  GTask *task = user_data;

  AsyncReadAll *data = g_task_get_task_data (task);

  gboolean got_eof = FALSE;

  if (result)

    {

      GError *error = NULL;

      gssize nread;

      nread = g_input_stream_read_finish (G_INPUT_STREAM (stream), result, &error);

      if (nread == -1)

        {

          g_task_return_error (task, error);

          g_object_unref (task);

          return;

        }

      g_assert_cmpint (nread, <=, data->to_read);

      data->to_read -= nread;

      data->bytes_read += nread;

      got_eof = (nread == 0);

    }

  if (got_eof || data->to_read == 0)

    {

      g_task_return_boolean (task, TRUE);

      g_object_unref (task);

    }

  else

    g_input_stream_read_async (G_INPUT_STREAM (stream),

                               data->buffer + data->bytes_read,

                               data->to_read,

                               g_task_get_priority (task),

                               g_task_get_cancellable (task),

                               read_all_callback, task);

}

static void

read_all_async_thread (GTask        *task,

                       gpointer      source_object,

                       gpointer      task_data,

                       GCancellable *cancellable)

{

  GInputStream *stream = source_object;

  AsyncReadAll *data = task_data;

  GError *error = NULL;

  if (g_input_stream_read_all (stream, data->buffer, data->to_read, &data->bytes_read,

                               g_task_get_cancellable (task), &error))

    g_task_return_boolean (task, TRUE);

  else

    g_task_return_error (task, error);

}

/**

 * g_input_stream_read_all_async:

 * @stream: A #GInputStream

 * @buffer: (array length=count) (element-type guint8): a buffer to

 *     read data into (which should be at least count bytes long)

 * @count: the number of bytes that will be read from the stream

 * @io_priority: the [I/O priority][io-priority] of the request

 * @cancellable: (nullable): 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 read of @count bytes from the stream into the

 * buffer starting at @buffer.

 *

 * This is the asynchronous equivalent of g_input_stream_read_all().

 *

 * Call g_input_stream_read_all_finish() to collect the result.

 *

 * 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.

 *

 * Since: 2.44

 **/

void

g_input_stream_read_all_async (GInputStream        *stream,

                               void                *buffer,

                               gsize                count,

                               int                  io_priority,

                               GCancellable        *cancellable,

                               GAsyncReadyCallback  callback,

                               gpointer             user_data)

{

  AsyncReadAll *data;

  GTask *task;

  g_return_if_fail (G_IS_INPUT_STREAM (stream));

  g_return_if_fail (buffer != NULL || count == 0);

  task = g_task_new (stream, cancellable, callback, user_data);

  data = g_slice_new0 (AsyncReadAll);

  data->buffer = buffer;

  data->to_read = count;

  g_task_set_source_tag (task, g_input_stream_read_all_async);

  g_task_set_task_data (task, data, free_async_read_all);

  g_task_set_priority (task, io_priority);

  /* If async reads are going to be handled via the threadpool anyway

   * then we may as well do it with a single dispatch instead of

   * bouncing in and out.

   */

  if (g_input_stream_async_read_is_via_threads (stream))

    {

      g_task_run_in_thread (task, read_all_async_thread);

      g_object_unref (task);

    }

  else

    read_all_callback (G_OBJECT (stream), NULL, task);

}

/**

 * g_input_stream_read_all_finish:

 * @stream: a #GInputStream

 * @result: a #GAsyncResult

 * @bytes_read: (out): location to store the number of bytes that was read from the stream

 * @error: a #GError location to store the error occurring, or %NULL to ignore

 *

 * Finishes an asynchronous stream read operation started with

 * g_input_stream_read_all_async().

 *

 * As a special exception to the normal conventions for functions that

 * use #GError, if this function returns %FALSE (and sets @error) then

 * @bytes_read will be set to the number of bytes that were successfully

 * read before the error was encountered.  This functionality is only

 * available from C.  If you need it from another language then you must

 * write your own loop around g_input_stream_read_async().

 *

 * Returns: %TRUE on success, %FALSE if there was an error

 *

 * Since: 2.44

 **/

gboolean

g_input_stream_read_all_finish (GInputStream  *stream,

                                GAsyncResult  *result,

                                gsize         *bytes_read,

                                GError       **error)

{

  GTask *task;

  g_return_val_if_fail (G_IS_INPUT_STREAM (stream), FALSE);

  g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);

  task = G_TASK (result);

  if (bytes_read)

    {

      AsyncReadAll *data = g_task_get_task_data (task);

      *bytes_read = data->bytes_read;

    }

  return g_task_propagate_boolean (task, error);

}

static void

read_bytes_callback (GObject      *stream,

		     GAsyncResult *result,

		     gpointer      user_data)

{

  GTask *task = user_data;

  guchar *buf = g_task_get_task_data (task);

  GError *error = NULL;

  gssize nread;

  GBytes *bytes = NULL;

  nread = g_input_stream_read_finish (G_INPUT_STREAM (stream),

				      result, &error);

  if (nread == -1)

    {

      g_free (buf);

      g_task_return_error (task, error);

    }

  else if (nread == 0)

    {

      g_free (buf);

      bytes = g_bytes_new_static ("", 0);

    }

  else

    bytes = g_bytes_new_take (buf, nread);

  if (bytes)

    g_task_return_pointer (task, bytes, (GDestroyNotify)g_bytes_unref);

  g_object_unref (task);

}

/**

 * g_input_stream_read_bytes_async: