| /* GIO - GLib Input, IO 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 <gfileiostream.h> |
| #include <gseekable.h> |
| #include "gasyncresult.h" |
| #include "gtask.h" |
| #include "gcancellable.h" |
| #include "gioerror.h" |
| #include "gfileoutputstream.h" |
| #include "glibintl.h" |
| |
| |
| /** |
| * SECTION:gfileiostream |
| * @short_description: File read and write streaming operations |
| * @include: gio/gio.h |
| * @see_also: #GIOStream, #GFileInputStream, #GFileOutputStream, #GSeekable |
| * |
| * GFileIOStream provides io streams that both read and write to the same |
| * file handle. |
| * |
| * GFileIOStream implements #GSeekable, which allows the io |
| * stream to jump to arbitrary positions in the file and to truncate |
| * the file, provided the filesystem of the file supports these |
| * operations. |
| * |
| * To find the position of a file io stream, use |
| * g_seekable_tell(). |
| * |
| * To find out if a file io stream supports seeking, use g_seekable_can_seek(). |
| * To position a file io stream, use g_seekable_seek(). |
| * To find out if a file io stream supports truncating, use |
| * g_seekable_can_truncate(). To truncate a file io |
| * stream, use g_seekable_truncate(). |
| * |
| * The default implementation of all the #GFileIOStream operations |
| * and the implementation of #GSeekable just call into the same operations |
| * on the output stream. |
| * Since: 2.22 |
| **/ |
| |
| static void g_file_io_stream_seekable_iface_init (GSeekableIface *iface); |
| static goffset g_file_io_stream_seekable_tell (GSeekable *seekable); |
| static gboolean g_file_io_stream_seekable_can_seek (GSeekable *seekable); |
| static gboolean g_file_io_stream_seekable_seek (GSeekable *seekable, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error); |
| static gboolean g_file_io_stream_seekable_can_truncate (GSeekable *seekable); |
| static gboolean g_file_io_stream_seekable_truncate (GSeekable *seekable, |
| goffset offset, |
| GCancellable *cancellable, |
| GError **error); |
| static void g_file_io_stream_real_query_info_async (GFileIOStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data); |
| static GFileInfo *g_file_io_stream_real_query_info_finish (GFileIOStream *stream, |
| GAsyncResult *result, |
| GError **error); |
| |
| struct _GFileIOStreamPrivate { |
| GAsyncReadyCallback outstanding_callback; |
| }; |
| |
| G_DEFINE_TYPE_WITH_CODE (GFileIOStream, g_file_io_stream, G_TYPE_IO_STREAM, |
| G_ADD_PRIVATE (GFileIOStream) |
| G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE, |
| g_file_io_stream_seekable_iface_init)) |
| |
| static void |
| g_file_io_stream_seekable_iface_init (GSeekableIface *iface) |
| { |
| iface->tell = g_file_io_stream_seekable_tell; |
| iface->can_seek = g_file_io_stream_seekable_can_seek; |
| iface->seek = g_file_io_stream_seekable_seek; |
| iface->can_truncate = g_file_io_stream_seekable_can_truncate; |
| iface->truncate_fn = g_file_io_stream_seekable_truncate; |
| } |
| |
| static void |
| g_file_io_stream_init (GFileIOStream *stream) |
| { |
| stream->priv = g_file_io_stream_get_instance_private (stream); |
| } |
| |
| /** |
| * g_file_io_stream_query_info: |
| * @stream: a #GFileIOStream. |
| * @attributes: a file attribute query string. |
| * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore. |
| * @error: a #GError, %NULL to ignore. |
| * |
| * Queries a file io stream for the given @attributes. |
| * This function blocks while querying the stream. For the asynchronous |
| * version of this function, see g_file_io_stream_query_info_async(). |
| * While the stream is blocked, the stream will set the pending flag |
| * internally, and any other operations on the stream will fail with |
| * %G_IO_ERROR_PENDING. |
| * |
| * Can fail if the stream was already closed (with @error being set to |
| * %G_IO_ERROR_CLOSED), the stream has pending operations (with @error being |
| * set to %G_IO_ERROR_PENDING), or if querying info is not supported for |
| * the stream's interface (with @error being set to %G_IO_ERROR_NOT_SUPPORTED). I |
| * all cases of failure, %NULL will be returned. |
| * |
| * 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 set, and %NULL will |
| * be returned. |
| * |
| * Returns: (transfer full): a #GFileInfo for the @stream, or %NULL on error. |
| * |
| * Since: 2.22 |
| **/ |
| GFileInfo * |
| g_file_io_stream_query_info (GFileIOStream *stream, |
| const char *attributes, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileIOStreamClass *class; |
| GIOStream *io_stream; |
| GFileInfo *info; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), NULL); |
| |
| io_stream = G_IO_STREAM (stream); |
| |
| if (!g_io_stream_set_pending (io_stream, error)) |
| return NULL; |
| |
| info = NULL; |
| |
| if (cancellable) |
| g_cancellable_push_current (cancellable); |
| |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| if (class->query_info) |
| info = class->query_info (stream, attributes, cancellable, error); |
| else |
| g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, |
| _("Stream doesn’t support query_info")); |
| |
| if (cancellable) |
| g_cancellable_pop_current (cancellable); |
| |
| g_io_stream_clear_pending (io_stream); |
| |
| return info; |
| } |
| |
| static void |
| async_ready_callback_wrapper (GObject *source_object, |
| GAsyncResult *res, |
| gpointer user_data) |
| { |
| GFileIOStream *stream = G_FILE_IO_STREAM (source_object); |
| |
| g_io_stream_clear_pending (G_IO_STREAM (stream)); |
| if (stream->priv->outstanding_callback) |
| (*stream->priv->outstanding_callback) (source_object, res, user_data); |
| g_object_unref (stream); |
| } |
| |
| /** |
| * g_file_io_stream_query_info_async: |
| * @stream: a #GFileIOStream. |
| * @attributes: a file attribute query string. |
| * @io_priority: the [I/O priority][gio-GIOScheduler] 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 |
| * |
| * Asynchronously queries the @stream for a #GFileInfo. When completed, |
| * @callback will be called with a #GAsyncResult which can be used to |
| * finish the operation with g_file_io_stream_query_info_finish(). |
| * |
| * For the synchronous version of this function, see |
| * g_file_io_stream_query_info(). |
| * |
| * Since: 2.22 |
| **/ |
| void |
| g_file_io_stream_query_info_async (GFileIOStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| GFileIOStreamClass *klass; |
| GIOStream *io_stream; |
| GError *error = NULL; |
| |
| g_return_if_fail (G_IS_FILE_IO_STREAM (stream)); |
| |
| io_stream = G_IO_STREAM (stream); |
| |
| if (!g_io_stream_set_pending (io_stream, &error)) |
| { |
| g_task_report_error (stream, callback, user_data, |
| g_file_io_stream_query_info_async, |
| error); |
| return; |
| } |
| |
| klass = G_FILE_IO_STREAM_GET_CLASS (stream); |
| |
| stream->priv->outstanding_callback = callback; |
| g_object_ref (stream); |
| klass->query_info_async (stream, attributes, io_priority, cancellable, |
| async_ready_callback_wrapper, user_data); |
| } |
| |
| /** |
| * g_file_io_stream_query_info_finish: |
| * @stream: a #GFileIOStream. |
| * @result: a #GAsyncResult. |
| * @error: a #GError, %NULL to ignore. |
| * |
| * Finalizes the asynchronous query started |
| * by g_file_io_stream_query_info_async(). |
| * |
| * Returns: (transfer full): A #GFileInfo for the finished query. |
| * |
| * Since: 2.22 |
| **/ |
| GFileInfo * |
| g_file_io_stream_query_info_finish (GFileIOStream *stream, |
| GAsyncResult *result, |
| GError **error) |
| { |
| GFileIOStreamClass *class; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), NULL); |
| g_return_val_if_fail (G_IS_ASYNC_RESULT (result), NULL); |
| |
| if (g_async_result_legacy_propagate_error (result, error)) |
| return NULL; |
| else if (g_async_result_is_tagged (result, g_file_io_stream_query_info_async)) |
| return g_task_propagate_pointer (G_TASK (result), error); |
| |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| return class->query_info_finish (stream, result, error); |
| } |
| |
| /** |
| * g_file_io_stream_get_etag: |
| * @stream: a #GFileIOStream. |
| * |
| * Gets the entity tag for the file when it has been written. |
| * This must be called after the stream has been written |
| * and closed, as the etag can change while writing. |
| * |
| * Returns: the entity tag for the stream. |
| * |
| * Since: 2.22 |
| **/ |
| char * |
| g_file_io_stream_get_etag (GFileIOStream *stream) |
| { |
| GFileIOStreamClass *class; |
| GIOStream *io_stream; |
| char *etag; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), NULL); |
| |
| io_stream = G_IO_STREAM (stream); |
| |
| if (!g_io_stream_is_closed (io_stream)) |
| { |
| g_warning ("stream is not closed yet, can't get etag"); |
| return NULL; |
| } |
| |
| etag = NULL; |
| |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| if (class->get_etag) |
| etag = class->get_etag (stream); |
| |
| return etag; |
| } |
| |
| static goffset |
| g_file_io_stream_tell (GFileIOStream *stream) |
| { |
| GFileIOStreamClass *class; |
| goffset offset; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), 0); |
| |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| |
| offset = 0; |
| if (class->tell) |
| offset = class->tell (stream); |
| |
| return offset; |
| } |
| |
| static goffset |
| g_file_io_stream_seekable_tell (GSeekable *seekable) |
| { |
| return g_file_io_stream_tell (G_FILE_IO_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_io_stream_can_seek (GFileIOStream *stream) |
| { |
| GFileIOStreamClass *class; |
| gboolean can_seek; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), FALSE); |
| |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| |
| can_seek = FALSE; |
| if (class->seek) |
| { |
| can_seek = TRUE; |
| if (class->can_seek) |
| can_seek = class->can_seek (stream); |
| } |
| |
| return can_seek; |
| } |
| |
| static gboolean |
| g_file_io_stream_seekable_can_seek (GSeekable *seekable) |
| { |
| return g_file_io_stream_can_seek (G_FILE_IO_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_io_stream_seek (GFileIOStream *stream, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileIOStreamClass *class; |
| GIOStream *io_stream; |
| gboolean res; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), FALSE); |
| |
| io_stream = G_IO_STREAM (stream); |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| |
| if (!class->seek) |
| { |
| g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, |
| _("Seek not supported on stream")); |
| return FALSE; |
| } |
| |
| if (!g_io_stream_set_pending (io_stream, error)) |
| return FALSE; |
| |
| if (cancellable) |
| g_cancellable_push_current (cancellable); |
| |
| res = class->seek (stream, offset, type, cancellable, error); |
| |
| if (cancellable) |
| g_cancellable_pop_current (cancellable); |
| |
| g_io_stream_clear_pending (io_stream); |
| |
| return res; |
| } |
| |
| static gboolean |
| g_file_io_stream_seekable_seek (GSeekable *seekable, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| return g_file_io_stream_seek (G_FILE_IO_STREAM (seekable), |
| offset, type, cancellable, error); |
| } |
| |
| static gboolean |
| g_file_io_stream_can_truncate (GFileIOStream *stream) |
| { |
| GFileIOStreamClass *class; |
| gboolean can_truncate; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), FALSE); |
| |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| |
| can_truncate = FALSE; |
| if (class->truncate_fn) |
| { |
| can_truncate = TRUE; |
| if (class->can_truncate) |
| can_truncate = class->can_truncate (stream); |
| } |
| |
| return can_truncate; |
| } |
| |
| static gboolean |
| g_file_io_stream_seekable_can_truncate (GSeekable *seekable) |
| { |
| return g_file_io_stream_can_truncate (G_FILE_IO_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_io_stream_truncate (GFileIOStream *stream, |
| goffset size, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileIOStreamClass *class; |
| GIOStream *io_stream; |
| gboolean res; |
| |
| g_return_val_if_fail (G_IS_FILE_IO_STREAM (stream), FALSE); |
| |
| io_stream = G_IO_STREAM (stream); |
| class = G_FILE_IO_STREAM_GET_CLASS (stream); |
| |
| if (!class->truncate_fn) |
| { |
| g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, |
| _("Truncate not supported on stream")); |
| return FALSE; |
| } |
| |
| if (!g_io_stream_set_pending (io_stream, error)) |
| return FALSE; |
| |
| if (cancellable) |
| g_cancellable_push_current (cancellable); |
| |
| res = class->truncate_fn (stream, size, cancellable, error); |
| |
| if (cancellable) |
| g_cancellable_pop_current (cancellable); |
| |
| g_io_stream_clear_pending (io_stream); |
| |
| return res; |
| } |
| |
| static gboolean |
| g_file_io_stream_seekable_truncate (GSeekable *seekable, |
| goffset size, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| return g_file_io_stream_truncate (G_FILE_IO_STREAM (seekable), |
| size, cancellable, error); |
| } |
| /***************************************************** |
| * Default implementations based on output stream * |
| *****************************************************/ |
| |
| static goffset |
| g_file_io_stream_real_tell (GFileIOStream *stream) |
| { |
| GOutputStream *out; |
| GSeekable *seekable; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| seekable = G_SEEKABLE (out); |
| |
| return g_seekable_tell (seekable); |
| } |
| |
| static gboolean |
| g_file_io_stream_real_can_seek (GFileIOStream *stream) |
| { |
| GOutputStream *out; |
| GSeekable *seekable; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| seekable = G_SEEKABLE (out); |
| |
| return g_seekable_can_seek (seekable); |
| } |
| |
| static gboolean |
| g_file_io_stream_real_seek (GFileIOStream *stream, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GOutputStream *out; |
| GSeekable *seekable; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| seekable = G_SEEKABLE (out); |
| |
| return g_seekable_seek (seekable, offset, type, cancellable, error); |
| } |
| |
| static gboolean |
| g_file_io_stream_real_can_truncate (GFileIOStream *stream) |
| { |
| GOutputStream *out; |
| GSeekable *seekable; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| seekable = G_SEEKABLE (out); |
| |
| return g_seekable_can_truncate (seekable); |
| } |
| |
| static gboolean |
| g_file_io_stream_real_truncate_fn (GFileIOStream *stream, |
| goffset size, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GOutputStream *out; |
| GSeekable *seekable; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| seekable = G_SEEKABLE (out); |
| |
| return g_seekable_truncate (seekable, size, cancellable, error); |
| } |
| |
| static char * |
| g_file_io_stream_real_get_etag (GFileIOStream *stream) |
| { |
| GOutputStream *out; |
| GFileOutputStream *file_out; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| file_out = G_FILE_OUTPUT_STREAM (out); |
| |
| return g_file_output_stream_get_etag (file_out); |
| } |
| |
| static GFileInfo * |
| g_file_io_stream_real_query_info (GFileIOStream *stream, |
| const char *attributes, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GOutputStream *out; |
| GFileOutputStream *file_out; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| file_out = G_FILE_OUTPUT_STREAM (out); |
| |
| return g_file_output_stream_query_info (file_out, |
| attributes, cancellable, error); |
| } |
| |
| typedef struct { |
| GObject *object; |
| GAsyncReadyCallback callback; |
| gpointer user_data; |
| } AsyncOpWrapper; |
| |
| static AsyncOpWrapper * |
| async_op_wrapper_new (gpointer object, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| AsyncOpWrapper *data; |
| |
| data = g_new0 (AsyncOpWrapper, 1); |
| data->object = g_object_ref (object); |
| data->callback = callback; |
| data->user_data = user_data; |
| |
| return data; |
| } |
| |
| static void |
| async_op_wrapper_callback (GObject *source_object, |
| GAsyncResult *res, |
| gpointer user_data) |
| { |
| AsyncOpWrapper *data = user_data; |
| data->callback (data->object, res, data->user_data); |
| g_object_unref (data->object); |
| g_free (data); |
| } |
| |
| static void |
| g_file_io_stream_real_query_info_async (GFileIOStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| GOutputStream *out; |
| GFileOutputStream *file_out; |
| AsyncOpWrapper *data; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| file_out = G_FILE_OUTPUT_STREAM (out); |
| |
| data = async_op_wrapper_new (stream, callback, user_data); |
| g_file_output_stream_query_info_async (file_out, |
| attributes, io_priority, |
| cancellable, async_op_wrapper_callback, data); |
| } |
| |
| static GFileInfo * |
| g_file_io_stream_real_query_info_finish (GFileIOStream *stream, |
| GAsyncResult *res, |
| GError **error) |
| { |
| GOutputStream *out; |
| GFileOutputStream *file_out; |
| |
| out = g_io_stream_get_output_stream (G_IO_STREAM (stream)); |
| file_out = G_FILE_OUTPUT_STREAM (out); |
| |
| return g_file_output_stream_query_info_finish (file_out, res, error); |
| } |
| |
| static void |
| g_file_io_stream_class_init (GFileIOStreamClass *klass) |
| { |
| klass->tell = g_file_io_stream_real_tell; |
| klass->can_seek = g_file_io_stream_real_can_seek; |
| klass->seek = g_file_io_stream_real_seek; |
| klass->can_truncate = g_file_io_stream_real_can_truncate; |
| klass->truncate_fn = g_file_io_stream_real_truncate_fn; |
| klass->query_info = g_file_io_stream_real_query_info; |
| klass->query_info_async = g_file_io_stream_real_query_info_async; |
| klass->query_info_finish = g_file_io_stream_real_query_info_finish; |
| klass->get_etag = g_file_io_stream_real_get_etag; |
| } |