/* GIO - GLib Input, Output and Streaming Library * * Copyright (C) 2006-2007 Red Hat, Inc. * Copyright (C) 2007 Jürg Billeter * * 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 . * * Author: Christian Kellner */ #include "config.h" #include "gbufferedinputstream.h" #include "ginputstream.h" #include "gcancellable.h" #include "gasyncresult.h" #include "gtask.h" #include "gseekable.h" #include "gioerror.h" #include #include "glibintl.h" /** * SECTION:gbufferedinputstream * @short_description: Buffered Input Stream * @include: gio/gio.h * @see_also: #GFilterInputStream, #GInputStream * * Buffered input stream implements #GFilterInputStream and provides * for buffered reads. * * By default, #GBufferedInputStream's buffer size is set at 4 kilobytes. * * To create a buffered input stream, use g_buffered_input_stream_new(), * or g_buffered_input_stream_new_sized() to specify the buffer's size at * construction. * * To get the size of a buffer within a buffered input stream, use * g_buffered_input_stream_get_buffer_size(). To change the size of a * buffered input stream's buffer, use * g_buffered_input_stream_set_buffer_size(). Note that the buffer's size * cannot be reduced below the size of the data within the buffer. */ #define DEFAULT_BUFFER_SIZE 4096 struct _GBufferedInputStreamPrivate { guint8 *buffer; gsize len; gsize pos; gsize end; GAsyncReadyCallback outstanding_callback; }; enum { PROP_0, PROP_BUFSIZE }; static void g_buffered_input_stream_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec); static void g_buffered_input_stream_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec); static void g_buffered_input_stream_finalize (GObject *object); static gssize g_buffered_input_stream_skip (GInputStream *stream, gsize count, GCancellable *cancellable, GError **error); static void g_buffered_input_stream_skip_async (GInputStream *stream, gsize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data); static gssize g_buffered_input_stream_skip_finish (GInputStream *stream, GAsyncResult *result, GError **error); static gssize g_buffered_input_stream_read (GInputStream *stream, void *buffer, gsize count, GCancellable *cancellable, GError **error); static gssize g_buffered_input_stream_real_fill (GBufferedInputStream *stream, gssize count, GCancellable *cancellable, GError **error); static void g_buffered_input_stream_real_fill_async (GBufferedInputStream *stream, gssize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data); static gssize g_buffered_input_stream_real_fill_finish (GBufferedInputStream *stream, GAsyncResult *result, GError **error); static void g_buffered_input_stream_seekable_iface_init (GSeekableIface *iface); static goffset g_buffered_input_stream_tell (GSeekable *seekable); static gboolean g_buffered_input_stream_can_seek (GSeekable *seekable); static gboolean g_buffered_input_stream_seek (GSeekable *seekable, goffset offset, GSeekType type, GCancellable *cancellable, GError **error); static gboolean g_buffered_input_stream_can_truncate (GSeekable *seekable); static gboolean g_buffered_input_stream_truncate (GSeekable *seekable, goffset offset, GCancellable *cancellable, GError **error); static void compact_buffer (GBufferedInputStream *stream); G_DEFINE_TYPE_WITH_CODE (GBufferedInputStream, g_buffered_input_stream, G_TYPE_FILTER_INPUT_STREAM, G_ADD_PRIVATE (GBufferedInputStream) G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE, g_buffered_input_stream_seekable_iface_init)) static void g_buffered_input_stream_class_init (GBufferedInputStreamClass *klass) { GObjectClass *object_class; GInputStreamClass *istream_class; GBufferedInputStreamClass *bstream_class; object_class = G_OBJECT_CLASS (klass); object_class->get_property = g_buffered_input_stream_get_property; object_class->set_property = g_buffered_input_stream_set_property; object_class->finalize = g_buffered_input_stream_finalize; istream_class = G_INPUT_STREAM_CLASS (klass); istream_class->skip = g_buffered_input_stream_skip; istream_class->skip_async = g_buffered_input_stream_skip_async; istream_class->skip_finish = g_buffered_input_stream_skip_finish; istream_class->read_fn = g_buffered_input_stream_read; bstream_class = G_BUFFERED_INPUT_STREAM_CLASS (klass); bstream_class->fill = g_buffered_input_stream_real_fill; bstream_class->fill_async = g_buffered_input_stream_real_fill_async; bstream_class->fill_finish = g_buffered_input_stream_real_fill_finish; g_object_class_install_property (object_class, PROP_BUFSIZE, g_param_spec_uint ("buffer-size", P_("Buffer Size"), P_("The size of the backend buffer"), 1, G_MAXUINT, DEFAULT_BUFFER_SIZE, G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_NAME|G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB)); } /** * g_buffered_input_stream_get_buffer_size: * @stream: a #GBufferedInputStream * * Gets the size of the input buffer. * * Returns: the current buffer size. */ gsize g_buffered_input_stream_get_buffer_size (GBufferedInputStream *stream) { g_return_val_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream), 0); return stream->priv->len; } /** * g_buffered_input_stream_set_buffer_size: * @stream: a #GBufferedInputStream * @size: a #gsize * * Sets the size of the internal buffer of @stream to @size, or to the * size of the contents of the buffer. The buffer can never be resized * smaller than its current contents. */ void g_buffered_input_stream_set_buffer_size (GBufferedInputStream *stream, gsize size) { GBufferedInputStreamPrivate *priv; gsize in_buffer; guint8 *buffer; g_return_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream)); priv = stream->priv; if (priv->len == size) return; if (priv->buffer) { in_buffer = priv->end - priv->pos; /* Never resize smaller than current buffer contents */ size = MAX (size, in_buffer); buffer = g_malloc (size); memcpy (buffer, priv->buffer + priv->pos, in_buffer); priv->len = size; priv->pos = 0; priv->end = in_buffer; g_free (priv->buffer); priv->buffer = buffer; } else { priv->len = size; priv->pos = 0; priv->end = 0; priv->buffer = g_malloc (size); } g_object_notify (G_OBJECT (stream), "buffer-size"); } static void g_buffered_input_stream_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec) { GBufferedInputStream *bstream; bstream = G_BUFFERED_INPUT_STREAM (object); switch (prop_id) { case PROP_BUFSIZE: g_buffered_input_stream_set_buffer_size (bstream, g_value_get_uint (value)); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void g_buffered_input_stream_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec) { GBufferedInputStreamPrivate *priv; GBufferedInputStream *bstream; bstream = G_BUFFERED_INPUT_STREAM (object); priv = bstream->priv; switch (prop_id) { case PROP_BUFSIZE: g_value_set_uint (value, priv->len); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void g_buffered_input_stream_finalize (GObject *object) { GBufferedInputStreamPrivate *priv; GBufferedInputStream *stream; stream = G_BUFFERED_INPUT_STREAM (object); priv = stream->priv; g_free (priv->buffer); G_OBJECT_CLASS (g_buffered_input_stream_parent_class)->finalize (object); } static void g_buffered_input_stream_seekable_iface_init (GSeekableIface *iface) { iface->tell = g_buffered_input_stream_tell; iface->can_seek = g_buffered_input_stream_can_seek; iface->seek = g_buffered_input_stream_seek; iface->can_truncate = g_buffered_input_stream_can_truncate; iface->truncate_fn = g_buffered_input_stream_truncate; } static void g_buffered_input_stream_init (GBufferedInputStream *stream) { stream->priv = g_buffered_input_stream_get_instance_private (stream); } /** * g_buffered_input_stream_new: * @base_stream: a #GInputStream * * Creates a new #GInputStream from the given @base_stream, with * a buffer set to the default size (4 kilobytes). * * Returns: a #GInputStream for the given @base_stream. */ GInputStream * g_buffered_input_stream_new (GInputStream *base_stream) { GInputStream *stream; g_return_val_if_fail (G_IS_INPUT_STREAM (base_stream), NULL); stream = g_object_new (G_TYPE_BUFFERED_INPUT_STREAM, "base-stream", base_stream, NULL); return stream; } /** * g_buffered_input_stream_new_sized: * @base_stream: a #GInputStream * @size: a #gsize * * Creates a new #GBufferedInputStream from the given @base_stream, * with a buffer set to @size. * * Returns: a #GInputStream. */ GInputStream * g_buffered_input_stream_new_sized (GInputStream *base_stream, gsize size) { GInputStream *stream; g_return_val_if_fail (G_IS_INPUT_STREAM (base_stream), NULL); stream = g_object_new (G_TYPE_BUFFERED_INPUT_STREAM, "base-stream", base_stream, "buffer-size", (guint)size, NULL); return stream; } /** * g_buffered_input_stream_fill: * @stream: a #GBufferedInputStream * @count: the number of bytes that will be read from the stream * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore * @error: location to store the error occurring, or %NULL to ignore * * Tries to read @count bytes from the stream into the buffer. * Will block during this read. * * If @count is zero, returns zero and does nothing. A value of @count * larger than %G_MAXSSIZE will cause a %G_IO_ERROR_INVALID_ARGUMENT error. * * On success, the number of bytes read into the buffer is returned. * It is not an error if this is not the same as the requested size, as it * can happen e.g. near the end of a file. Zero is returned on end of file * (or if @count is zero), but never otherwise. * * If @count is -1 then the attempted read size is equal to the number of * bytes that are required to fill the buffer. * * 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 returned. If an * operation was partially finished when the operation was cancelled the * partial result will be returned, without an error. * * On error -1 is returned and @error is set accordingly. * * For the asynchronous, non-blocking, version of this function, see * g_buffered_input_stream_fill_async(). * * Returns: the number of bytes read into @stream's buffer, up to @count, * or -1 on error. */ gssize g_buffered_input_stream_fill (GBufferedInputStream *stream, gssize count, GCancellable *cancellable, GError **error) { GBufferedInputStreamClass *class; GInputStream *input_stream; gssize res; g_return_val_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream), -1); input_stream = G_INPUT_STREAM (stream); if (count < -1) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT, _("Too large count value passed to %s"), G_STRFUNC); return -1; } if (!g_input_stream_set_pending (input_stream, error)) return -1; if (cancellable) g_cancellable_push_current (cancellable); class = G_BUFFERED_INPUT_STREAM_GET_CLASS (stream); res = class->fill (stream, count, cancellable, error); if (cancellable) g_cancellable_pop_current (cancellable); g_input_stream_clear_pending (input_stream); return res; } static void async_fill_callback_wrapper (GObject *source_object, GAsyncResult *res, gpointer user_data) { GBufferedInputStream *stream = G_BUFFERED_INPUT_STREAM (source_object); g_input_stream_clear_pending (G_INPUT_STREAM (stream)); (*stream->priv->outstanding_callback) (source_object, res, user_data); g_object_unref (stream); } /** * g_buffered_input_stream_fill_async: * @stream: a #GBufferedInputStream * @count: the number of bytes that will be read from the stream * @io_priority: the [I/O priority][io-priority] of the request * @cancellable: (nullable): optional #GCancellable object * @callback: (scope async): a #GAsyncReadyCallback * @user_data: (closure): a #gpointer * * Reads data into @stream's buffer asynchronously, up to @count size. * @io_priority can be used to prioritize reads. For the synchronous * version of this function, see g_buffered_input_stream_fill(). * * If @count is -1 then the attempted read size is equal to the number * of bytes that are required to fill the buffer. */ void g_buffered_input_stream_fill_async (GBufferedInputStream *stream, gssize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GBufferedInputStreamClass *class; GError *error = NULL; g_return_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream)); if (count == 0) { GTask *task; task = g_task_new (stream, cancellable, callback, user_data); g_task_set_source_tag (task, g_buffered_input_stream_fill_async); g_task_return_int (task, 0); g_object_unref (task); return; } if (count < -1) { g_task_report_new_error (stream, callback, user_data, g_buffered_input_stream_fill_async, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT, _("Too large count value passed to %s"), G_STRFUNC); return; } if (!g_input_stream_set_pending (G_INPUT_STREAM (stream), &error)) { g_task_report_error (stream, callback, user_data, g_buffered_input_stream_fill_async, error); return; } class = G_BUFFERED_INPUT_STREAM_GET_CLASS (stream); stream->priv->outstanding_callback = callback; g_object_ref (stream); class->fill_async (stream, count, io_priority, cancellable, async_fill_callback_wrapper, user_data); } /** * g_buffered_input_stream_fill_finish: * @stream: a #GBufferedInputStream * @result: a #GAsyncResult * @error: a #GError * * Finishes an asynchronous read. * * Returns: a #gssize of the read stream, or `-1` on an error. */ gssize g_buffered_input_stream_fill_finish (GBufferedInputStream *stream, GAsyncResult *result, GError **error) { GBufferedInputStreamClass *class; g_return_val_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream), -1); g_return_val_if_fail (G_IS_ASYNC_RESULT (result), -1); if (g_async_result_legacy_propagate_error (result, error)) return -1; else if (g_async_result_is_tagged (result, g_buffered_input_stream_fill_async)) return g_task_propagate_int (G_TASK (result), error); class = G_BUFFERED_INPUT_STREAM_GET_CLASS (stream); return class->fill_finish (stream, result, error); } /** * g_buffered_input_stream_get_available: * @stream: #GBufferedInputStream * * Gets the size of the available data within the stream. * * Returns: size of the available stream. */ gsize g_buffered_input_stream_get_available (GBufferedInputStream *stream) { g_return_val_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream), -1); return stream->priv->end - stream->priv->pos; } /** * g_buffered_input_stream_peek: * @stream: a #GBufferedInputStream * @buffer: (array length=count) (element-type guint8): a pointer to * an allocated chunk of memory * @offset: a #gsize * @count: a #gsize * * Peeks in the buffer, copying data of size @count into @buffer, * offset @offset bytes. * * Returns: a #gsize of the number of bytes peeked, or -1 on error. */ gsize g_buffered_input_stream_peek (GBufferedInputStream *stream, void *buffer, gsize offset, gsize count) { gsize available; gsize end; g_return_val_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream), -1); g_return_val_if_fail (buffer != NULL, -1); available = g_buffered_input_stream_get_available (stream); if (offset > available) return 0; end = MIN (offset + count, available); count = end - offset; memcpy (buffer, stream->priv->buffer + stream->priv->pos + offset, count); return count; } /** * g_buffered_input_stream_peek_buffer: * @stream: a #GBufferedInputStream * @count: (out): a #gsize to get the number of bytes available in the buffer * * Returns the buffer with the currently available bytes. The returned * buffer must not be modified and will become invalid when reading from * the stream or filling the buffer. * * Returns: (array length=count) (element-type guint8) (transfer none): * read-only buffer */ const void* g_buffered_input_stream_peek_buffer (GBufferedInputStream *stream, gsize *count) { GBufferedInputStreamPrivate *priv; g_return_val_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream), NULL); priv = stream->priv; if (count) *count = priv->end - priv->pos; return priv->buffer + priv->pos; } static void compact_buffer (GBufferedInputStream *stream) { GBufferedInputStreamPrivate *priv; gsize current_size; priv = stream->priv; current_size = priv->end - priv->pos; memmove (priv->buffer, priv->buffer + priv->pos, current_size); priv->pos = 0; priv->end = current_size; } static gssize g_buffered_input_stream_real_fill (GBufferedInputStream *stream, gssize count, GCancellable *cancellable, GError **error) { GBufferedInputStreamPrivate *priv; GInputStream *base_stream; gssize nread; gsize in_buffer; priv = stream->priv; if (count == -1) count = priv->len; in_buffer = priv->end - priv->pos; /* Never fill more than can fit in the buffer */ count = MIN (count, priv->len - in_buffer); /* If requested length does not fit at end, compact */ if (priv->len - priv->end < count) compact_buffer (stream); base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream; nread = g_input_stream_read (base_stream, priv->buffer + priv->end, count, cancellable, error); if (nread > 0) priv->end += nread; return nread; } static gssize g_buffered_input_stream_skip (GInputStream *stream, gsize count, GCancellable *cancellable, GError **error) { GBufferedInputStream *bstream; GBufferedInputStreamPrivate *priv; GBufferedInputStreamClass *class; GInputStream *base_stream; gsize available, bytes_skipped; gssize nread; bstream = G_BUFFERED_INPUT_STREAM (stream); priv = bstream->priv; available = priv->end - priv->pos; if (count <= available) { priv->pos += count; return count; } /* Full request not available, skip all currently available and * request refill for more */ priv->pos = 0; priv->end = 0; bytes_skipped = available; count -= available; if (bytes_skipped > 0) error = NULL; /* Ignore further errors if we already read some data */ if (count > priv->len) { /* Large request, shortcut buffer */ base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream; nread = g_input_stream_skip (base_stream, count, cancellable, error); if (nread < 0 && bytes_skipped == 0) return -1; if (nread > 0) bytes_skipped += nread; return bytes_skipped; } class = G_BUFFERED_INPUT_STREAM_GET_CLASS (stream); nread = class->fill (bstream, priv->len, cancellable, error); if (nread < 0) { if (bytes_skipped == 0) return -1; else return bytes_skipped; } available = priv->end - priv->pos; count = MIN (count, available); bytes_skipped += count; priv->pos += count; return bytes_skipped; } static gssize g_buffered_input_stream_read (GInputStream *stream, void *buffer, gsize count, GCancellable *cancellable, GError **error) { GBufferedInputStream *bstream; GBufferedInputStreamPrivate *priv; GBufferedInputStreamClass *class; GInputStream *base_stream; gsize available, bytes_read; gssize nread; bstream = G_BUFFERED_INPUT_STREAM (stream); priv = bstream->priv; available = priv->end - priv->pos; if (count <= available) { memcpy (buffer, priv->buffer + priv->pos, count); priv->pos += count; return count; } /* Full request not available, read all currently available and * request refill for more */ memcpy (buffer, priv->buffer + priv->pos, available); priv->pos = 0; priv->end = 0; bytes_read = available; count -= available; if (bytes_read > 0) error = NULL; /* Ignore further errors if we already read some data */ if (count > priv->len) { /* Large request, shortcut buffer */ base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream; nread = g_input_stream_read (base_stream, (char *)buffer + bytes_read, count, cancellable, error); if (nread < 0 && bytes_read == 0) return -1; if (nread > 0) bytes_read += nread; return bytes_read; } class = G_BUFFERED_INPUT_STREAM_GET_CLASS (stream); nread = class->fill (bstream, priv->len, cancellable, error); if (nread < 0) { if (bytes_read == 0) return -1; else return bytes_read; } available = priv->end - priv->pos; count = MIN (count, available); memcpy ((char *)buffer + bytes_read, (char *)priv->buffer + priv->pos, count); bytes_read += count; priv->pos += count; return bytes_read; } static goffset g_buffered_input_stream_tell (GSeekable *seekable) { GBufferedInputStream *bstream; GBufferedInputStreamPrivate *priv; GInputStream *base_stream; GSeekable *base_stream_seekable; gsize available; goffset base_offset; bstream = G_BUFFERED_INPUT_STREAM (seekable); priv = bstream->priv; base_stream = G_FILTER_INPUT_STREAM (seekable)->base_stream; if (!G_IS_SEEKABLE (base_stream)) return 0; base_stream_seekable = G_SEEKABLE (base_stream); available = priv->end - priv->pos; base_offset = g_seekable_tell (base_stream_seekable); return base_offset - available; } static gboolean g_buffered_input_stream_can_seek (GSeekable *seekable) { GInputStream *base_stream; base_stream = G_FILTER_INPUT_STREAM (seekable)->base_stream; return G_IS_SEEKABLE (base_stream) && g_seekable_can_seek (G_SEEKABLE (base_stream)); } static gboolean g_buffered_input_stream_seek (GSeekable *seekable, goffset offset, GSeekType type, GCancellable *cancellable, GError **error) { GBufferedInputStream *bstream; GBufferedInputStreamPrivate *priv; GInputStream *base_stream; GSeekable *base_stream_seekable; bstream = G_BUFFERED_INPUT_STREAM (seekable); priv = bstream->priv; base_stream = G_FILTER_INPUT_STREAM (seekable)->base_stream; if (!G_IS_SEEKABLE (base_stream)) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, _("Seek not supported on base stream")); return FALSE; } base_stream_seekable = G_SEEKABLE (base_stream); if (type == G_SEEK_CUR) { if (offset <= priv->end - priv->pos && offset >= -priv->pos) { priv->pos += offset; return TRUE; } else { offset -= priv->end - priv->pos; } } if (g_seekable_seek (base_stream_seekable, offset, type, cancellable, error)) { priv->pos = 0; priv->end = 0; return TRUE; } else { return FALSE; } } static gboolean g_buffered_input_stream_can_truncate (GSeekable *seekable) { return FALSE; } static gboolean g_buffered_input_stream_truncate (GSeekable *seekable, goffset offset, GCancellable *cancellable, GError **error) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED, _("Cannot truncate GBufferedInputStream")); return FALSE; } /** * g_buffered_input_stream_read_byte: * @stream: a #GBufferedInputStream * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore * @error: location to store the error occurring, or %NULL to ignore * * Tries to read a single byte from the stream or the buffer. Will block * during this read. * * On success, the byte read from the stream is returned. On end of stream * -1 is returned but it's not an exceptional error and @error is not set. * * 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 returned. If an * operation was partially finished when the operation was cancelled the * partial result will be returned, without an error. * * On error -1 is returned and @error is set accordingly. * * Returns: the byte read from the @stream, or -1 on end of stream or error. */ int g_buffered_input_stream_read_byte (GBufferedInputStream *stream, GCancellable *cancellable, GError **error) { GBufferedInputStreamPrivate *priv; GBufferedInputStreamClass *class; GInputStream *input_stream; gsize available; gssize nread; g_return_val_if_fail (G_IS_BUFFERED_INPUT_STREAM (stream), -1); priv = stream->priv; input_stream = G_INPUT_STREAM (stream); if (g_input_stream_is_closed (input_stream)) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_CLOSED, _("Stream is already closed")); return -1; } if (!g_input_stream_set_pending (input_stream, error)) return -1; available = priv->end - priv->pos; if (available != 0) { g_input_stream_clear_pending (input_stream); return priv->buffer[priv->pos++]; } /* Byte not available, request refill for more */ if (cancellable) g_cancellable_push_current (cancellable); priv->pos = 0; priv->end = 0; class = G_BUFFERED_INPUT_STREAM_GET_CLASS (stream); nread = class->fill (stream, priv->len, cancellable, error); if (cancellable) g_cancellable_pop_current (cancellable); g_input_stream_clear_pending (input_stream); if (nread <= 0) return -1; /* error or end of stream */ return priv->buffer[priv->pos++]; } /* ************************** */ /* Async stuff implementation */ /* ************************** */ static void fill_async_callback (GObject *source_object, GAsyncResult *result, gpointer user_data) { GError *error; gssize res; GTask *task = user_data; error = NULL; res = g_input_stream_read_finish (G_INPUT_STREAM (source_object), result, &error); if (res == -1) g_task_return_error (task, error); else { GBufferedInputStream *stream; GBufferedInputStreamPrivate *priv; stream = g_task_get_source_object (task); priv = G_BUFFERED_INPUT_STREAM (stream)->priv; g_assert_cmpint (priv->end + res, <=, priv->len); priv->end += res; g_task_return_int (task, res); } g_object_unref (task); } static void g_buffered_input_stream_real_fill_async (GBufferedInputStream *stream, gssize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GBufferedInputStreamPrivate *priv; GInputStream *base_stream; GTask *task; gsize in_buffer; priv = stream->priv; if (count == -1) count = priv->len; in_buffer = priv->end - priv->pos; /* Never fill more than can fit in the buffer */ count = MIN (count, priv->len - in_buffer); /* If requested length does not fit at end, compact */ if (priv->len - priv->end < count) compact_buffer (stream); task = g_task_new (stream, cancellable, callback, user_data); g_task_set_source_tag (task, g_buffered_input_stream_real_fill_async); base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream; g_input_stream_read_async (base_stream, priv->buffer + priv->end, count, io_priority, cancellable, fill_async_callback, task); } static gssize g_buffered_input_stream_real_fill_finish (GBufferedInputStream *stream, GAsyncResult *result, GError **error) { g_return_val_if_fail (g_task_is_valid (result, stream), -1); return g_task_propagate_int (G_TASK (result), error); } typedef struct { gssize bytes_skipped; gssize count; } SkipAsyncData; static void free_skip_async_data (gpointer _data) { SkipAsyncData *data = _data; g_slice_free (SkipAsyncData, data); } static void large_skip_callback (GObject *source_object, GAsyncResult *result, gpointer user_data) { GTask *task = G_TASK (user_data); SkipAsyncData *data; GError *error; gssize nread; data = g_task_get_task_data (task); error = NULL; nread = g_input_stream_skip_finish (G_INPUT_STREAM (source_object), result, &error); /* Only report the error if we've not already read some data */ if (nread < 0 && data->bytes_skipped == 0) g_task_return_error (task, error); else { if (error) g_error_free (error); if (nread > 0) data->bytes_skipped += nread; g_task_return_int (task, data->bytes_skipped); } g_object_unref (task); } static void skip_fill_buffer_callback (GObject *source_object, GAsyncResult *result, gpointer user_data) { GTask *task = G_TASK (user_data); GBufferedInputStream *bstream; GBufferedInputStreamPrivate *priv; SkipAsyncData *data; GError *error; gssize nread; gsize available; bstream = G_BUFFERED_INPUT_STREAM (source_object); priv = bstream->priv; data = g_task_get_task_data (task); error = NULL; nread = g_buffered_input_stream_fill_finish (bstream, result, &error); if (nread < 0 && data->bytes_skipped == 0) g_task_return_error (task, error); else { if (error) g_error_free (error); if (nread > 0) { available = priv->end - priv->pos; data->count = MIN (data->count, available); data->bytes_skipped += data->count; priv->pos += data->count; } g_task_return_int (task, data->bytes_skipped); } g_object_unref (task); } static void g_buffered_input_stream_skip_async (GInputStream *stream, gsize count, int io_priority, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data) { GBufferedInputStream *bstream; GBufferedInputStreamPrivate *priv; GBufferedInputStreamClass *class; GInputStream *base_stream; gsize available; GTask *task; SkipAsyncData *data; bstream = G_BUFFERED_INPUT_STREAM (stream); priv = bstream->priv; data = g_slice_new (SkipAsyncData); data->bytes_skipped = 0; task = g_task_new (stream, cancellable, callback, user_data); g_task_set_source_tag (task, g_buffered_input_stream_skip_async); g_task_set_task_data (task, data, free_skip_async_data); available = priv->end - priv->pos; if (count <= available) { priv->pos += count; g_task_return_int (task, count); g_object_unref (task); return; } /* Full request not available, skip all currently available * and request refill for more */ priv->pos = 0; priv->end = 0; count -= available; data->bytes_skipped = available; data->count = count; if (count > priv->len) { /* Large request, shortcut buffer */ base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream; g_input_stream_skip_async (base_stream, count, io_priority, cancellable, large_skip_callback, task); } else { class = G_BUFFERED_INPUT_STREAM_GET_CLASS (stream); class->fill_async (bstream, priv->len, io_priority, cancellable, skip_fill_buffer_callback, task); } } static gssize g_buffered_input_stream_skip_finish (GInputStream *stream, GAsyncResult *result, GError **error) { g_return_val_if_fail (g_task_is_valid (result, stream), -1); return g_task_propagate_int (G_TASK (result), error); }