| /* 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 <alexl@redhat.com> |
| */ |
| |
| #include "config.h" |
| |
| #include <glib.h> |
| #include <gfileinputstream.h> |
| #include <gseekable.h> |
| #include "gsimpleasyncresult.h" |
| #include "gcancellable.h" |
| #include "gasyncresult.h" |
| #include "gioerror.h" |
| #include "glibintl.h" |
| |
| #include "gioalias.h" |
| |
| /** |
| * SECTION:gfileinputstream |
| * @short_description: File input streaming operations |
| * @include: gio/gio.h |
| * @see_also: #GInputStream, #GDataInputStream, #GSeekable |
| * |
| * GFileInputStream provides input streams that take their |
| * content from a file. |
| * |
| * GFileInputStream implements #GSeekable, which allows the input |
| * stream to jump to arbitrary positions in the file, provided the |
| * filesystem of the file allows it. To find the position of a file |
| * input stream, use g_seekable_tell(). To find out if a file input |
| * stream supports seeking, use g_seekable_stream_can_seek(). |
| * To position a file input stream, use g_seekable_seek(). |
| **/ |
| |
| static void g_file_input_stream_seekable_iface_init (GSeekableIface *iface); |
| static goffset g_file_input_stream_seekable_tell (GSeekable *seekable); |
| static gboolean g_file_input_stream_seekable_can_seek (GSeekable *seekable); |
| static gboolean g_file_input_stream_seekable_seek (GSeekable *seekable, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error); |
| static gboolean g_file_input_stream_seekable_can_truncate (GSeekable *seekable); |
| static gboolean g_file_input_stream_seekable_truncate (GSeekable *seekable, |
| goffset offset, |
| GCancellable *cancellable, |
| GError **error); |
| static void g_file_input_stream_real_query_info_async (GFileInputStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data); |
| static GFileInfo *g_file_input_stream_real_query_info_finish (GFileInputStream *stream, |
| GAsyncResult *result, |
| GError **error); |
| |
| |
| G_DEFINE_TYPE_WITH_CODE (GFileInputStream, g_file_input_stream, G_TYPE_INPUT_STREAM, |
| G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE, |
| g_file_input_stream_seekable_iface_init)) |
| |
| struct _GFileInputStreamPrivate { |
| GAsyncReadyCallback outstanding_callback; |
| }; |
| |
| static void |
| g_file_input_stream_class_init (GFileInputStreamClass *klass) |
| { |
| g_type_class_add_private (klass, sizeof (GFileInputStreamPrivate)); |
| |
| klass->query_info_async = g_file_input_stream_real_query_info_async; |
| klass->query_info_finish = g_file_input_stream_real_query_info_finish; |
| } |
| |
| static void |
| g_file_input_stream_seekable_iface_init (GSeekableIface *iface) |
| { |
| iface->tell = g_file_input_stream_seekable_tell; |
| iface->can_seek = g_file_input_stream_seekable_can_seek; |
| iface->seek = g_file_input_stream_seekable_seek; |
| iface->can_truncate = g_file_input_stream_seekable_can_truncate; |
| iface->truncate_fn = g_file_input_stream_seekable_truncate; |
| } |
| |
| static void |
| g_file_input_stream_init (GFileInputStream *stream) |
| { |
| stream->priv = G_TYPE_INSTANCE_GET_PRIVATE (stream, |
| G_TYPE_FILE_INPUT_STREAM, |
| GFileInputStreamPrivate); |
| } |
| |
| /** |
| * g_file_input_stream_query_info: |
| * @stream: a #GFileInputStream. |
| * @attributes: a file attribute query string. |
| * @cancellable: optional #GCancellable object, %NULL to ignore. |
| * @error: a #GError location to store the error occuring, or %NULL to |
| * ignore. |
| * |
| * Queries a file input stream the given @attributes. This function blocks |
| * while querying the stream. For the asynchronous (non-blocking) version |
| * of this function, see g_file_input_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. |
| * |
| * Returns: a #GFileInfo, or %NULL on error. |
| **/ |
| GFileInfo * |
| g_file_input_stream_query_info (GFileInputStream *stream, |
| const char *attributes, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileInputStreamClass *class; |
| GInputStream *input_stream; |
| GFileInfo *info; |
| |
| g_return_val_if_fail (G_IS_FILE_INPUT_STREAM (stream), NULL); |
| |
| input_stream = G_INPUT_STREAM (stream); |
| |
| if (!g_input_stream_set_pending (input_stream, error)) |
| return NULL; |
| |
| info = NULL; |
| |
| if (cancellable) |
| g_cancellable_push_current (cancellable); |
| |
| class = G_FILE_INPUT_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_input_stream_clear_pending (input_stream); |
| |
| return info; |
| } |
| |
| static void |
| async_ready_callback_wrapper (GObject *source_object, |
| GAsyncResult *res, |
| gpointer user_data) |
| { |
| GFileInputStream *stream = G_FILE_INPUT_STREAM (source_object); |
| |
| g_input_stream_clear_pending (G_INPUT_STREAM (stream)); |
| if (stream->priv->outstanding_callback) |
| (*stream->priv->outstanding_callback) (source_object, res, user_data); |
| g_object_unref (stream); |
| } |
| |
| /** |
| * g_file_input_stream_query_info_async: |
| * @stream: a #GFileInputStream. |
| * @attributes: a file attribute query string. |
| * @io_priority: the <link linkend="io-priority">I/O priority</link> |
| * 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 |
| * |
| * Queries the stream information asynchronously. |
| * When the operation is finished @callback will be called. |
| * You can then call g_file_input_stream_query_info_finish() |
| * to get the result of the operation. |
| * |
| * For the synchronous version of this function, |
| * see g_file_input_stream_query_info(). |
| * |
| * 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 |
| * |
| **/ |
| void |
| g_file_input_stream_query_info_async (GFileInputStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| GFileInputStreamClass *klass; |
| GInputStream *input_stream; |
| GError *error = NULL; |
| |
| g_return_if_fail (G_IS_FILE_INPUT_STREAM (stream)); |
| |
| input_stream = G_INPUT_STREAM (stream); |
| |
| if (!g_input_stream_set_pending (input_stream, &error)) |
| { |
| g_simple_async_report_gerror_in_idle (G_OBJECT (stream), |
| callback, |
| user_data, |
| error); |
| g_error_free (error); |
| return; |
| } |
| |
| klass = G_FILE_INPUT_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_input_stream_query_info_finish: |
| * @stream: a #GFileInputStream. |
| * @result: a #GAsyncResult. |
| * @error: a #GError location to store the error occuring, |
| * or %NULL to ignore. |
| * |
| * Finishes an asynchronous info query operation. |
| * |
| * Returns: #GFileInfo. |
| **/ |
| GFileInfo * |
| g_file_input_stream_query_info_finish (GFileInputStream *stream, |
| GAsyncResult *result, |
| GError **error) |
| { |
| GSimpleAsyncResult *simple; |
| GFileInputStreamClass *class; |
| |
| g_return_val_if_fail (G_IS_FILE_INPUT_STREAM (stream), NULL); |
| g_return_val_if_fail (G_IS_ASYNC_RESULT (result), NULL); |
| |
| if (G_IS_SIMPLE_ASYNC_RESULT (result)) |
| { |
| simple = G_SIMPLE_ASYNC_RESULT (result); |
| if (g_simple_async_result_propagate_error (simple, error)) |
| return NULL; |
| } |
| |
| class = G_FILE_INPUT_STREAM_GET_CLASS (stream); |
| return class->query_info_finish (stream, result, error); |
| } |
| |
| static goffset |
| g_file_input_stream_tell (GFileInputStream *stream) |
| { |
| GFileInputStreamClass *class; |
| goffset offset; |
| |
| g_return_val_if_fail (G_IS_FILE_INPUT_STREAM (stream), 0); |
| |
| class = G_FILE_INPUT_STREAM_GET_CLASS (stream); |
| |
| offset = 0; |
| if (class->tell) |
| offset = class->tell (stream); |
| |
| return offset; |
| } |
| |
| static goffset |
| g_file_input_stream_seekable_tell (GSeekable *seekable) |
| { |
| return g_file_input_stream_tell (G_FILE_INPUT_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_input_stream_can_seek (GFileInputStream *stream) |
| { |
| GFileInputStreamClass *class; |
| gboolean can_seek; |
| |
| g_return_val_if_fail (G_IS_FILE_INPUT_STREAM (stream), FALSE); |
| |
| class = G_FILE_INPUT_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_input_stream_seekable_can_seek (GSeekable *seekable) |
| { |
| return g_file_input_stream_can_seek (G_FILE_INPUT_STREAM (seekable)); |
| } |
| |
| static gboolean |
| g_file_input_stream_seek (GFileInputStream *stream, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GFileInputStreamClass *class; |
| GInputStream *input_stream; |
| gboolean res; |
| |
| g_return_val_if_fail (G_IS_FILE_INPUT_STREAM (stream), FALSE); |
| |
| input_stream = G_INPUT_STREAM (stream); |
| class = G_FILE_INPUT_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_input_stream_set_pending (input_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_input_stream_clear_pending (input_stream); |
| |
| return res; |
| } |
| |
| static gboolean |
| g_file_input_stream_seekable_seek (GSeekable *seekable, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| return g_file_input_stream_seek (G_FILE_INPUT_STREAM (seekable), |
| offset, type, cancellable, error); |
| } |
| |
| static gboolean |
| g_file_input_stream_seekable_can_truncate (GSeekable *seekable) |
| { |
| return FALSE; |
| } |
| |
| static gboolean |
| g_file_input_stream_seekable_truncate (GSeekable *seekable, |
| goffset offset, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, |
| _("Truncate not allowed on input stream")); |
| return FALSE; |
| } |
| |
| /******************************************** |
| * Default implementation of async ops * |
| ********************************************/ |
| |
| typedef struct { |
| char *attributes; |
| GFileInfo *info; |
| } QueryInfoAsyncData; |
| |
| static void |
| query_info_data_free (QueryInfoAsyncData *data) |
| { |
| if (data->info) |
| g_object_unref (data->info); |
| g_free (data->attributes); |
| g_free (data); |
| } |
| |
| static void |
| query_info_async_thread (GSimpleAsyncResult *res, |
| GObject *object, |
| GCancellable *cancellable) |
| { |
| GFileInputStreamClass *class; |
| GError *error = NULL; |
| QueryInfoAsyncData *data; |
| GFileInfo *info; |
| |
| data = g_simple_async_result_get_op_res_gpointer (res); |
| |
| info = NULL; |
| |
| class = G_FILE_INPUT_STREAM_GET_CLASS (object); |
| if (class->query_info) |
| info = class->query_info (G_FILE_INPUT_STREAM (object), data->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_simple_async_result_set_from_error (res, error); |
| g_error_free (error); |
| } |
| else |
| data->info = info; |
| } |
| |
| static void |
| g_file_input_stream_real_query_info_async (GFileInputStream *stream, |
| const char *attributes, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| GSimpleAsyncResult *res; |
| QueryInfoAsyncData *data; |
| |
| data = g_new0 (QueryInfoAsyncData, 1); |
| data->attributes = g_strdup (attributes); |
| |
| res = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, g_file_input_stream_real_query_info_async); |
| g_simple_async_result_set_op_res_gpointer (res, data, (GDestroyNotify)query_info_data_free); |
| |
| g_simple_async_result_run_in_thread (res, query_info_async_thread, io_priority, cancellable); |
| g_object_unref (res); |
| } |
| |
| static GFileInfo * |
| g_file_input_stream_real_query_info_finish (GFileInputStream *stream, |
| GAsyncResult *res, |
| GError **error) |
| { |
| GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (res); |
| QueryInfoAsyncData *data; |
| |
| g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_file_input_stream_real_query_info_async); |
| |
| data = g_simple_async_result_get_op_res_gpointer (simple); |
| if (data->info) |
| return g_object_ref (data->info); |
| |
| return NULL; |
| } |
| |
| #define __G_FILE_INPUT_STREAM_C__ |
| #include "gioaliasdef.c" |
| |
