mirror of
https://gitlab.gnome.org/GNOME/glib.git
synced 2024-11-14 05:16:18 +01:00
f99be75ff9
The docs mentions a separate seekable API for the various file streams which don't actually exists. Change this to refer to the generic GSeekable calls.
474 lines
15 KiB
C
474 lines
15 KiB
C
/* 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"
|
|
|