| /* GIO - GLib Input, Output and Streaming Library |
| * |
| * Copyright (C) 2006-2007 Red Hat, Inc. |
| * |
| * SPDX-License-Identifier: LGPL-2.1-or-later |
| * |
| * 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 <gfileoutputstream.h> |
| #include <gseekable.h> |
| #include "gasyncresult.h" |
| #include "gtask.h" |
| #include "gcancellable.h" |
| #include "gioerror.h" |
| #include "glibintl.h" |
| |
| |
| /** |
| * GFileOutputStream: |
| * |
| * `GFileOutputStream` provides output streams that write their |
| * content to a file. |
| * |
| * `GFileOutputStream` implements [iface@Gio.Seekable], which allows the output |
| * 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 output stream, use [method@Gio.Seekable.tell]. |
| * To find out if a file output stream supports seeking, use |
| * [method@Gio.Seekable.can_seek].To position a file output stream, use |
| * [method@Gio.Seekable.seek]. To find out if a file output stream supports |
| * truncating, use [method@Gio.Seekable.can_truncate]. To truncate a file output |
| * stream, use [method@Gio.Seekable.truncate]. |
| **/ |
| |
| static void g_file_output_stream_seekable_iface_init (GSeekableIface *iface); |
| static goffset g_file_output_stream_seekable_tell (GSeekable *seekable); |
| static gboolean g_file_output_stream_seekable_can_seek (GSeekable *seekable); |
| static gboolean g_file_output_stream_seekable_seek (GSeekable *seekable, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error); |
| static gboolean g_file_output_stream_seekable_can_truncate (GSeekable *seekable); |
| static gboolean g_file_output_stream_seekable_truncate (GSeekable *seekable, |
| goffset offset, |
| GCancellable *cancellable, |
| GError **error); |
| static void g_file_output_stream_real_query_info_async (GFileOutputStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data); |
| static GFileInfo *g_file_output_stream_real_query_info_finish (GFileOutputStream *stream, |
| GAsyncResult *result, |
| GError **error); |
| |
| struct _GFileOutputStreamPrivate { |
| GAsyncReadyCallback outstanding_callback; |
| }; |
| |
| G_DEFINE_TYPE_WITH_CODE (GFileOutputStream, g_file_output_stream, G_TYPE_OUTPUT_STREAM, |
| G_ADD_PRIVATE (GFileOutputStream) |
| G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE, |
| g_file_output_stream_seekable_iface_init)); |
| |
| static void |
| g_file_output_stream_class_init (GFileOutputStreamClass *klass) |
| { |
| klass->query_info_async = g_file_output_stream_real_query_info_async; |
| klass->query_info_finish = g_file_output_stream_real_query_info_finish; |
| } |
| |
| static void |
| g_file_output_stream_seekable_iface_init (GSeekableIface *iface) |
| { |
| iface->tell = g_file_output_stream_seekable_tell; |
| iface->can_seek = g_file_output_stream_seekable_can_seek; |
| iface->seek = g_file_output_stream_seekable_seek; |
| iface->can_truncate = g_file_output_stream_seekable_can_truncate; |
| iface->truncate_fn = g_file_output_stream_seekable_truncate; |
| } |
| |
| static void |
| g_file_output_stream_init (GFileOutputStream *stream) |
| { |
| stream->priv = g_file_output_stream_get_instance_private (stream); |
| } |
| |
| /** |
| * g_file_output_stream_query_info: |
| * @stream: a #GFileOutputStream. |
| * @attributes: a file attribute query string. |
| * @cancellable: optional #GCancellable object, %NULL to ignore. |
| * @error: a #GError, %NULL to ignore. |
| * |
| * Queries a file output stream for the given @attributes. |
| * This function blocks while querying the stream. For the asynchronous |
| * version of this function, see g_file_output_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). In |
| * 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. |
| **/ |
| GFileInfo * |
| g_file_output_stream_query_info (GFileOutputStream *stream, |
| const char *attributes, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileOutputStreamClass *class; |
| GOutputStream *output_stream; |
| GFileInfo *info; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_STREAM (stream), NULL); |
| |
| output_stream = G_OUTPUT_STREAM (stream); |
| |
| if (!g_output_stream_set_pending (output_stream, error)) |
| return NULL; |
| |
| info = NULL; |
| |
| if (cancellable) |
| g_cancellable_push_current (cancellable); |
| |
| class = G_FILE_OUTPUT_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_output_stream_clear_pending (output_stream); |
| |
| return info; |
| } |
| |
| static void |
| async_ready_callback_wrapper (GObject *source_object, |
| GAsyncResult *res, |
| gpointer user_data) |
| { |
| GFileOutputStream *stream = G_FILE_OUTPUT_STREAM (source_object); |
| |
| g_output_stream_clear_pending (G_OUTPUT_STREAM (stream)); |
| if (stream->priv->outstanding_callback) |
| (*stream->priv->outstanding_callback) (source_object, res, user_data); |
| g_object_unref (stream); |
| } |
| |
| /** |
| * g_file_output_stream_query_info_async: |
| * @stream: a #GFileOutputStream. |
| * @attributes: a file attribute query string. |
| * @io_priority: the [I/O priority](iface.AsyncResult.html#io-priority) of the |
| * request |
| * @cancellable: optional #GCancellable object, %NULL to ignore. |
| * @callback: callback to call when the request is satisfied |
| * @user_data: 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_output_stream_query_info_finish(). |
| * |
| * For the synchronous version of this function, see |
| * g_file_output_stream_query_info(). |
| * |
| **/ |
| void |
| g_file_output_stream_query_info_async (GFileOutputStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| GFileOutputStreamClass *klass; |
| GOutputStream *output_stream; |
| GError *error = NULL; |
| |
| g_return_if_fail (G_IS_FILE_OUTPUT_STREAM (stream)); |
| |
| output_stream = G_OUTPUT_STREAM (stream); |
| |
| if (!g_output_stream_set_pending (output_stream, &error)) |
| { |
| g_task_report_error (stream, callback, user_data, |
| g_file_output_stream_query_info_async, |
| error); |
| return; |
| } |
| |
| klass = G_FILE_OUTPUT_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_output_stream_query_info_finish: |
| * @stream: a #GFileOutputStream. |
| * @result: a #GAsyncResult. |
| * @error: a #GError, %NULL to ignore. |
| * |
| * Finalizes the asynchronous query started |
| * by g_file_output_stream_query_info_async(). |
| * |
| * Returns: (transfer full): A #GFileInfo for the finished query. |
| **/ |
| GFileInfo * |
| g_file_output_stream_query_info_finish (GFileOutputStream *stream, |
| GAsyncResult *result, |
| GError **error) |
| { |
| GFileOutputStreamClass *class; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_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_output_stream_query_info_async)) |
| return g_task_propagate_pointer (G_TASK (result), error); |
| |
| class = G_FILE_OUTPUT_STREAM_GET_CLASS (stream); |
| return class->query_info_finish (stream, result, error); |
| } |
| |
| /** |
| * g_file_output_stream_get_etag: |
| * @stream: a #GFileOutputStream. |
| * |
| * 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: (nullable) (transfer full): the entity tag for the stream. |
| **/ |
| char * |
| g_file_output_stream_get_etag (GFileOutputStream *stream) |
| { |
| GFileOutputStreamClass *class; |
| GOutputStream *output_stream; |
| char *etag; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_STREAM (stream), NULL); |
| |
| output_stream = G_OUTPUT_STREAM (stream); |
| |
| if (!g_output_stream_is_closed (output_stream)) |
| { |
| g_warning ("stream is not closed yet, can't get etag"); |
| return NULL; |
| } |
| |
| etag = NULL; |
| |
| class = G_FILE_OUTPUT_STREAM_GET_CLASS (stream); |
| if (class->get_etag) |
| etag = class->get_etag (stream); |
| |
| return etag; |
| } |
| |
| static goffset |
| g_file_output_stream_tell (GFileOutputStream *stream) |
| { |
| GFileOutputStreamClass *class; |
| goffset offset; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_STREAM (stream), 0); |
| |
| class = G_FILE_OUTPUT_STREAM_GET_CLASS (stream); |
| |
| offset = 0; |
| if (class->tell) |
| offset = class->tell (stream); |
| |
| return offset; |
| } |
| |
| static goffset |
| g_file_output_stream_seekable_tell (GSeekable *seekable) |
| { |
| return g_file_output_stream_tell (G_FILE_OUTPUT_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_output_stream_can_seek (GFileOutputStream *stream) |
| { |
| GFileOutputStreamClass *class; |
| gboolean can_seek; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_STREAM (stream), FALSE); |
| |
| class = G_FILE_OUTPUT_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_output_stream_seekable_can_seek (GSeekable *seekable) |
| { |
| return g_file_output_stream_can_seek (G_FILE_OUTPUT_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_output_stream_seek (GFileOutputStream *stream, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileOutputStreamClass *class; |
| GOutputStream *output_stream; |
| gboolean res; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_STREAM (stream), FALSE); |
| |
| output_stream = G_OUTPUT_STREAM (stream); |
| class = G_FILE_OUTPUT_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_output_stream_set_pending (output_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_output_stream_clear_pending (output_stream); |
| |
| return res; |
| } |
| |
| static gboolean |
| g_file_output_stream_seekable_seek (GSeekable *seekable, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| return g_file_output_stream_seek (G_FILE_OUTPUT_STREAM (seekable), |
| offset, type, cancellable, error); |
| } |
| |
| static gboolean |
| g_file_output_stream_can_truncate (GFileOutputStream *stream) |
| { |
| GFileOutputStreamClass *class; |
| gboolean can_truncate; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_STREAM (stream), FALSE); |
| |
| class = G_FILE_OUTPUT_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_output_stream_seekable_can_truncate (GSeekable *seekable) |
| { |
| return g_file_output_stream_can_truncate (G_FILE_OUTPUT_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_output_stream_truncate (GFileOutputStream *stream, |
| goffset size, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileOutputStreamClass *class; |
| GOutputStream *output_stream; |
| gboolean res; |
| |
| g_return_val_if_fail (G_IS_FILE_OUTPUT_STREAM (stream), FALSE); |
| |
| output_stream = G_OUTPUT_STREAM (stream); |
| class = G_FILE_OUTPUT_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_output_stream_set_pending (output_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_output_stream_clear_pending (output_stream); |
| |
| return res; |
| } |
| |
| static gboolean |
| g_file_output_stream_seekable_truncate (GSeekable *seekable, |
| goffset size, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| return g_file_output_stream_truncate (G_FILE_OUTPUT_STREAM (seekable), |
| size, cancellable, error); |
| } |
| /******************************************** |
| * Default implementation of async ops * |
| ********************************************/ |
| |
| static void |
| query_info_async_thread (GTask *task, |
| gpointer source_object, |
| gpointer task_data, |
| GCancellable *cancellable) |
| { |
| GFileOutputStream *stream = source_object; |
| const char *attributes = task_data; |
| GFileOutputStreamClass *class; |
| GError *error = NULL; |
| GFileInfo *info = NULL; |
| |
| class = G_FILE_OUTPUT_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 (info == NULL) |
| g_task_return_error (task, error); |
| else |
| g_task_return_pointer (task, info, g_object_unref); |
| } |
| |
| static void |
| g_file_output_stream_real_query_info_async (GFileOutputStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| GTask *task; |
| |
| task = g_task_new (stream, cancellable, callback, user_data); |
| g_task_set_source_tag (task, g_file_output_stream_real_query_info_async); |
| g_task_set_task_data (task, g_strdup (attributes), g_free); |
| g_task_set_priority (task, io_priority); |
| |
| g_task_run_in_thread (task, query_info_async_thread); |
| g_object_unref (task); |
| } |
| |
| static GFileInfo * |
| g_file_output_stream_real_query_info_finish (GFileOutputStream *stream, |
| GAsyncResult *res, |
| GError **error) |
| { |
| g_return_val_if_fail (g_task_is_valid (res, stream), NULL); |
| |
| return g_task_propagate_pointer (G_TASK (res), error); |
| } |