* 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.
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
* Authors:
* Christian Kellner <gicmo@gnome.org>
#include "config.h"
#include "gmemoryoutputstream.h"
#include "goutputstream.h"
+#include "gpollableoutputstream.h"
#include "gseekable.h"
-#include "gsimpleasyncresult.h"
+#include "gtask.h"
#include "gioerror.h"
#include "string.h"
#include "glibintl.h"
* #GMemoryOutputStream is a class for using arbitrary
* memory chunks as output for GIO streaming output operations.
*
+ * As of GLib 2.34, #GMemoryOutputStream trivially implements
+ * #GPollableOutputStream: it always polls as ready.
*/
#define MIN_ARRAY_SIZE 16
PROP_DESTROY_FUNCTION
};
-struct _GMemoryOutputStreamPrivate {
-
+struct _GMemoryOutputStreamPrivate
+{
gpointer data; /* Write buffer */
gsize len; /* Current length of the data buffer. Can change with resizing. */
gsize valid_len; /* The part of data that has been written to */
GCancellable *cancellable,
GError **error);
-static void g_memory_output_stream_write_async (GOutputStream *stream,
- const void *buffer,
- gsize count,
- int io_priority,
- GCancellable *cancellable,
- GAsyncReadyCallback callback,
- gpointer data);
-static gssize g_memory_output_stream_write_finish (GOutputStream *stream,
- GAsyncResult *result,
- GError **error);
static void g_memory_output_stream_close_async (GOutputStream *stream,
int io_priority,
GCancellable *cancellable,
GCancellable *cancellable,
GError **error);
+static gboolean g_memory_output_stream_is_writable (GPollableOutputStream *stream);
+static GSource *g_memory_output_stream_create_source (GPollableOutputStream *stream,
+ GCancellable *cancellable);
+
+static void g_memory_output_stream_pollable_iface_init (GPollableOutputStreamInterface *iface);
+
G_DEFINE_TYPE_WITH_CODE (GMemoryOutputStream, g_memory_output_stream, G_TYPE_OUTPUT_STREAM,
+ G_ADD_PRIVATE (GMemoryOutputStream)
G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE,
- g_memory_output_stream_seekable_iface_init))
+ g_memory_output_stream_seekable_iface_init);
+ G_IMPLEMENT_INTERFACE (G_TYPE_POLLABLE_OUTPUT_STREAM,
+ g_memory_output_stream_pollable_iface_init))
static void
GOutputStreamClass *ostream_class;
GObjectClass *gobject_class;
- g_type_class_add_private (klass, sizeof (GMemoryOutputStreamPrivate));
-
gobject_class = G_OBJECT_CLASS (klass);
gobject_class->set_property = g_memory_output_stream_set_property;
gobject_class->get_property = g_memory_output_stream_get_property;
ostream_class->write_fn = g_memory_output_stream_write;
ostream_class->close_fn = g_memory_output_stream_close;
- ostream_class->write_async = g_memory_output_stream_write_async;
- ostream_class->write_finish = g_memory_output_stream_write_finish;
ostream_class->close_async = g_memory_output_stream_close_async;
ostream_class->close_finish = g_memory_output_stream_close_finish;
}
static void
+g_memory_output_stream_pollable_iface_init (GPollableOutputStreamInterface *iface)
+{
+ iface->is_writable = g_memory_output_stream_is_writable;
+ iface->create_source = g_memory_output_stream_create_source;
+}
+
+static void
g_memory_output_stream_set_property (GObject *object,
guint prop_id,
const GValue *value,
static void
g_memory_output_stream_init (GMemoryOutputStream *stream)
{
- stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream,
- G_TYPE_MEMORY_OUTPUT_STREAM,
- GMemoryOutputStreamPrivate);
+ stream->priv = g_memory_output_stream_get_instance_private (stream);
stream->priv->pos = 0;
stream->priv->valid_len = 0;
}
/**
* g_memory_output_stream_new: (skip)
- * @data: pointer to a chunk of memory to use, or %NULL
+ * @data: (allow-none): pointer to a chunk of memory to use, or %NULL
* @size: the size of @data
- * @realloc_function: a function with realloc() semantics (like g_realloc())
+ * @realloc_function: (allow-none): a function with realloc() semantics (like g_realloc())
* to be called when @data needs to be grown, or %NULL
- * @destroy_function: a function to be called on @data when the stream is
+ * @destroy_function: (allow-none): a function to be called on @data when the stream is
* finalized, or %NULL
*
* Creates a new #GMemoryOutputStream.
*
- * If @data is non-%NULL, the stream will use that for its internal storage.
+ * In most cases this is not the function you want. See
+ * g_memory_output_stream_new_resizable() instead.
+ *
+ * If @data is non-%NULL, the stream will use that for its internal storage.
+ *
* If @realloc_fn is non-%NULL, it will be used for resizing the internal
- * storage when necessary. To construct a fixed-size output stream,
- * pass %NULL as @realloc_fn.
+ * storage when necessary and the stream will be considered resizable.
+ * In that case, the stream will start out being (conceptually) empty.
+ * @size is used only as a hint for how big @data is. Specifically,
+ * seeking to the end of a newly-created stream will seek to zero, not
+ * @size. Seeking past the end of the stream and then writing will
+ * introduce a zero-filled gap.
+ *
+ * If @realloc_fn is %NULL then the stream is fixed-sized. Seeking to
+ * the end will seek to @size exactly. Writing past the end will give
+ * an 'out of space' error. Attempting to seek past the end will fail.
+ * Unlike the resizable case, seeking to an offset within the stream and
+ * writing will preserve the bytes passed in as @data before that point
+ * and will return them as part of g_memory_output_stream_steal_data().
+ * If you intend to seek you should probably therefore ensure that @data
+ * is properly initialised.
*
- * |[
- * /* a stream that can grow */
+ * It is probably only meaningful to provide @data and @size in the case
+ * that you want a fixed-sized stream. Put another way: if @realloc_fn
+ * is non-%NULL then it makes most sense to give @data as %NULL and
+ * @size as 0 (allowing #GMemoryOutputStream to do the initial
+ * allocation for itself).
+ *
+ * |[<!-- language="C" -->
+ * // a stream that can grow
* stream = g_memory_output_stream_new (NULL, 0, realloc, free);
*
- * /* another stream that can grow */
+ * // another stream that can grow
* stream2 = g_memory_output_stream_new (NULL, 0, g_realloc, g_free);
*
- * /* a fixed-size stream */
+ * // a fixed-size stream
* data = malloc (200);
* stream3 = g_memory_output_stream_new (data, 200, NULL, free);
* ]|
*
- * Return value: A newly created #GMemoryOutputStream object.
+ * Returns: A newly created #GMemoryOutputStream object.
**/
GOutputStream *
g_memory_output_stream_new (gpointer data,
}
/**
+ * g_memory_output_stream_new_resizable:
+ *
+ * Creates a new #GMemoryOutputStream, using g_realloc() and g_free()
+ * for memory allocation.
+ *
+ * Since: 2.36
+ */
+GOutputStream *
+g_memory_output_stream_new_resizable (void)
+{
+ return g_memory_output_stream_new (NULL, 0, g_realloc, g_free);
+}
+
+/**
* g_memory_output_stream_get_data:
* @ostream: a #GMemoryOutputStream
*
* @ostream: a #GMemoryOutputStream
*
* Gets the size of the currently allocated data area (available from
- * g_memory_output_stream_get_data()). If the stream isn't
- * growable (no realloc was passed to g_memory_output_stream_new()) then
- * this is the maximum size of the stream and further writes
- * will return %G_IO_ERROR_NO_SPACE.
+ * g_memory_output_stream_get_data()).
+ *
+ * You probably don't want to use this function on resizable streams.
+ * See g_memory_output_stream_get_data_size() instead. For resizable
+ * streams the size returned by this function is an implementation
+ * detail and may be change at any time in response to operations on the
+ * stream.
*
- * Note that for growable streams the returned size may become invalid on
- * the next write or truncate operation on the stream.
+ * If the stream is fixed-sized (ie: no realloc was passed to
+ * g_memory_output_stream_new()) then this is the maximum size of the
+ * stream and further writes will return %G_IO_ERROR_NO_SPACE.
*
- * If you want the number of bytes currently written to the stream, use
- * g_memory_output_stream_get_data_size().
+ * In any case, if you want the number of bytes currently written to the
+ * stream, use g_memory_output_stream_get_data_size().
*
* Returns: the number of bytes allocated for the data buffer
*/
* g_memory_output_stream_get_data_size:
* @ostream: a #GMemoryOutputStream
*
- * Returns the number of bytes from the start up
- * to including the last byte written in the stream
- * that has not been truncated away.
+ * Returns the number of bytes from the start up to including the last
+ * byte written in the stream that has not been truncated away.
*
* Returns: the number of bytes written to the stream
*
return data;
}
+/**
+ * g_memory_output_stream_steal_as_bytes:
+ * @ostream: a #GMemoryOutputStream
+ *
+ * Returns data from the @ostream as a #GBytes. @ostream must be
+ * closed before calling this function.
+ *
+ * Returns: (transfer full): the stream's data
+ *
+ * Since: 2.34
+ **/
+GBytes *
+g_memory_output_stream_steal_as_bytes (GMemoryOutputStream *ostream)
+{
+ GBytes *result;
+
+ g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), NULL);
+ g_return_val_if_fail (g_output_stream_is_closed (G_OUTPUT_STREAM (ostream)), NULL);
+
+ result = g_bytes_new_with_free_func (ostream->priv->data,
+ ostream->priv->valid_len,
+ ostream->priv->destroy,
+ ostream->priv->data);
+ ostream->priv->data = NULL;
+
+ return result;
+}
+
static gboolean
array_resize (GMemoryOutputStream *ostream,
gsize size,
return TRUE;
}
-static gint
-g_nearest_pow (gint num)
+static gsize
+g_nearest_pow (gsize num)
{
- gint n = 1;
+ gsize n = 1;
- while (n < num)
+ while (n < num && n > 0)
n <<= 1;
return n;
if (priv->pos + count > priv->len)
{
- /* At least enought to fit the write, rounded up
- for greater than linear growth.
- TODO: This wastes a lot of memory at large stream sizes.
- Figure out a more rational allocation strategy. */
+ /* At least enough to fit the write, rounded up for greater than
+ * linear growth.
+ *
+ * Assuming that we're using something like realloc(), the kernel
+ * will overcommit memory to us, so doubling the size each time
+ * will keep the number of realloc calls low without wasting too
+ * much memory.
+ */
new_size = g_nearest_pow (priv->pos + count);
- /* Check for overflow again. We have only checked if
- pos + count > G_MAXSIZE, but it only catches the case of writing
- more than 4GiB total on a 32-bit system. There's still the problem
- of g_nearest_pow overflowing above 0x7fffffff, so we're
- effectively limited to 2GiB. */
- if (new_size < priv->len)
+ /* Check for overflow again. We have checked if
+ pos + count > G_MAXSIZE, but now check if g_nearest_pow () has
+ overflowed */
+ if (new_size == 0)
goto overflow;
new_size = MAX (new_size, MIN_ARRAY_SIZE);
}
static void
-g_memory_output_stream_write_async (GOutputStream *stream,
- const void *buffer,
- gsize count,
- int io_priority,
- GCancellable *cancellable,
- GAsyncReadyCallback callback,
- gpointer data)
-{
- GSimpleAsyncResult *simple;
- GError *error = NULL;
- gssize nwritten;
-
- nwritten = G_OUTPUT_STREAM_GET_CLASS (stream)->write_fn (stream,
- buffer,
- count,
- cancellable,
- &error);
-
- simple = g_simple_async_result_new (G_OBJECT (stream),
- callback,
- data,
- g_memory_output_stream_write_async);
-
- if (error)
- g_simple_async_result_take_error (simple, error);
- else
- g_simple_async_result_set_op_res_gssize (simple, nwritten);
- g_simple_async_result_complete_in_idle (simple);
- g_object_unref (simple);
-}
-
-static gssize
-g_memory_output_stream_write_finish (GOutputStream *stream,
- GAsyncResult *result,
- GError **error)
-{
- GSimpleAsyncResult *simple;
- gssize nwritten;
-
- simple = G_SIMPLE_ASYNC_RESULT (result);
-
- g_warn_if_fail (g_simple_async_result_get_source_tag (simple) ==
- g_memory_output_stream_write_async);
-
- nwritten = g_simple_async_result_get_op_res_gssize (simple);
-
- return nwritten;
-}
-
-static void
g_memory_output_stream_close_async (GOutputStream *stream,
int io_priority,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer data)
{
- GSimpleAsyncResult *simple;
-
- simple = g_simple_async_result_new (G_OBJECT (stream),
- callback,
- data,
- g_memory_output_stream_close_async);
+ GTask *task;
+ task = g_task_new (stream, cancellable, callback, data);
/* will always return TRUE */
g_memory_output_stream_close (stream, cancellable, NULL);
- g_simple_async_result_complete_in_idle (simple);
- g_object_unref (simple);
+ g_task_return_boolean (task, TRUE);
+ g_object_unref (task);
}
static gboolean
GAsyncResult *result,
GError **error)
{
- GSimpleAsyncResult *simple;
-
- simple = G_SIMPLE_ASYNC_RESULT (result);
+ g_return_val_if_fail (g_task_is_valid (result, stream), FALSE);
- g_warn_if_fail (g_simple_async_result_get_source_tag (simple) ==
- g_memory_output_stream_close_async);
-
- return TRUE;
+ return g_task_propagate_boolean (G_TASK (result), error);
}
static goffset
static gboolean
g_memory_output_stream_seek (GSeekable *seekable,
- goffset offset,
- GSeekType type,
- GCancellable *cancellable,
- GError **error)
+ goffset offset,
+ GSeekType type,
+ GCancellable *cancellable,
+ GError **error)
{
GMemoryOutputStream *stream;
GMemoryOutputStreamPrivate *priv;
break;
case G_SEEK_END:
- absolute = priv->len + offset;
+ /* For resizable streams, we consider the end to be the data
+ * length. For fixed-sized streams, we consider the end to be the
+ * size of the buffer.
+ */
+ if (priv->realloc_fn)
+ absolute = priv->valid_len + offset;
+ else
+ absolute = priv->len + offset;
break;
default:
return FALSE;
}
- if (absolute > priv->len)
+ /* Can't seek past the end of a fixed-size stream.
+ *
+ * Note: seeking to the non-existent byte at the end of a fixed-sized
+ * stream is valid (eg: a 1-byte fixed sized stream can have position
+ * 0 or 1). Therefore '>' is what we want.
+ * */
+ if (priv->realloc_fn == NULL && absolute > priv->len)
{
g_set_error_literal (error,
G_IO_ERROR,
ostream = G_MEMORY_OUTPUT_STREAM (seekable);
priv = ostream->priv;
+ /* We do not allow truncation of fixed-sized streams */
return priv->realloc_fn != NULL;
}
if (!array_resize (ostream, offset, FALSE, error))
return FALSE;
+ ostream->priv->valid_len = offset;
+
return TRUE;
}
+
+static gboolean
+g_memory_output_stream_is_writable (GPollableOutputStream *stream)
+{
+ return TRUE;
+}
+
+static GSource *
+g_memory_output_stream_create_source (GPollableOutputStream *stream,
+ GCancellable *cancellable)
+{
+ GSource *base_source, *pollable_source;
+
+ base_source = g_timeout_source_new (0);
+ pollable_source = g_pollable_source_new_full (stream, base_source, cancellable);
+ g_source_unref (base_source);
+
+ return pollable_source;
+}
projects / platform / upstream / glib.git / blobdiff