1 /* GIO - GLib Input, Output and Streaming Library
3 * Copyright (C) 2009 Red Hat, Inc.
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General
16 * Public License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
18 * Boston, MA 02111-1307, USA.
20 * Author: Alexander Larsson <alexl@redhat.com>
27 #include "gconverterinputstream.h"
28 #include "gpollableinputstream.h"
29 #include "gsimpleasyncresult.h"
30 #include "gcancellable.h"
31 #include "gioenumtypes.h"
37 * SECTION:gconverterinputstream
38 * @short_description: Converter Input Stream
40 * @see_also: #GInputStream, #GConverter
42 * Converter input stream implements #GInputStream and allows
43 * conversion of data of various types during reading.
45 * As of GLib 2.34, #GConverterInputStream implements
46 * #GPollableInputStream.
49 #define INITIAL_BUFFER_SIZE 4096
58 struct _GConverterInputStreamPrivate {
59 gboolean at_input_end;
62 GConverter *converter;
64 Buffer converted_buffer;
72 static void g_converter_input_stream_set_property (GObject *object,
76 static void g_converter_input_stream_get_property (GObject *object,
80 static void g_converter_input_stream_finalize (GObject *object);
81 static gssize g_converter_input_stream_read (GInputStream *stream,
84 GCancellable *cancellable,
87 static gboolean g_converter_input_stream_can_poll (GPollableInputStream *stream);
88 static gboolean g_converter_input_stream_is_readable (GPollableInputStream *stream);
89 static gssize g_converter_input_stream_read_nonblocking (GPollableInputStream *stream,
94 static GSource *g_converter_input_stream_create_source (GPollableInputStream *stream,
95 GCancellable *cancellable);
97 static void g_converter_input_stream_pollable_iface_init (GPollableInputStreamInterface *iface);
99 G_DEFINE_TYPE_WITH_CODE (GConverterInputStream,
100 g_converter_input_stream,
101 G_TYPE_FILTER_INPUT_STREAM,
102 G_ADD_PRIVATE (GConverterInputStream)
103 G_IMPLEMENT_INTERFACE (G_TYPE_POLLABLE_INPUT_STREAM,
104 g_converter_input_stream_pollable_iface_init))
107 g_converter_input_stream_class_init (GConverterInputStreamClass *klass)
109 GObjectClass *object_class;
110 GInputStreamClass *istream_class;
112 object_class = G_OBJECT_CLASS (klass);
113 object_class->get_property = g_converter_input_stream_get_property;
114 object_class->set_property = g_converter_input_stream_set_property;
115 object_class->finalize = g_converter_input_stream_finalize;
117 istream_class = G_INPUT_STREAM_CLASS (klass);
118 istream_class->read_fn = g_converter_input_stream_read;
120 g_object_class_install_property (object_class,
122 g_param_spec_object ("converter",
124 P_("The converter object"),
127 G_PARAM_CONSTRUCT_ONLY|
128 G_PARAM_STATIC_STRINGS));
133 g_converter_input_stream_pollable_iface_init (GPollableInputStreamInterface *iface)
135 iface->can_poll = g_converter_input_stream_can_poll;
136 iface->is_readable = g_converter_input_stream_is_readable;
137 iface->read_nonblocking = g_converter_input_stream_read_nonblocking;
138 iface->create_source = g_converter_input_stream_create_source;
142 g_converter_input_stream_finalize (GObject *object)
144 GConverterInputStreamPrivate *priv;
145 GConverterInputStream *stream;
147 stream = G_CONVERTER_INPUT_STREAM (object);
150 g_free (priv->input_buffer.data);
151 g_free (priv->converted_buffer.data);
153 g_object_unref (priv->converter);
155 G_OBJECT_CLASS (g_converter_input_stream_parent_class)->finalize (object);
159 g_converter_input_stream_set_property (GObject *object,
164 GConverterInputStream *cstream;
166 cstream = G_CONVERTER_INPUT_STREAM (object);
171 cstream->priv->converter = g_value_dup_object (value);
175 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
182 g_converter_input_stream_get_property (GObject *object,
187 GConverterInputStreamPrivate *priv;
188 GConverterInputStream *cstream;
190 cstream = G_CONVERTER_INPUT_STREAM (object);
191 priv = cstream->priv;
196 g_value_set_object (value, priv->converter);
200 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
206 g_converter_input_stream_init (GConverterInputStream *stream)
208 stream->priv = g_converter_input_stream_get_instance_private (stream);
212 * g_converter_input_stream_new:
213 * @base_stream: a #GInputStream
214 * @converter: a #GConverter
216 * Creates a new converter input stream for the @base_stream.
218 * Returns: a new #GInputStream.
221 g_converter_input_stream_new (GInputStream *base_stream,
222 GConverter *converter)
224 GInputStream *stream;
226 g_return_val_if_fail (G_IS_INPUT_STREAM (base_stream), NULL);
228 stream = g_object_new (G_TYPE_CONVERTER_INPUT_STREAM,
229 "base-stream", base_stream,
230 "converter", converter,
237 buffer_data_size (Buffer *buffer)
239 return buffer->end - buffer->start;
243 buffer_tailspace (Buffer *buffer)
245 return buffer->size - buffer->end;
249 buffer_data (Buffer *buffer)
251 return buffer->data + buffer->start;
255 buffer_consumed (Buffer *buffer,
258 buffer->start += count;
259 if (buffer->start == buffer->end)
260 buffer->start = buffer->end = 0;
264 buffer_read (Buffer *buffer,
268 memcpy (dest, buffer->data + buffer->start, count);
269 buffer_consumed (buffer, count);
273 compact_buffer (Buffer *buffer)
277 in_buffer = buffer_data_size (buffer);
278 memmove (buffer->data,
279 buffer->data + buffer->start,
281 buffer->end -= buffer->start;
286 grow_buffer (Buffer *buffer)
289 gsize size, in_buffer;
291 if (buffer->size == 0)
292 size = INITIAL_BUFFER_SIZE;
294 size = buffer->size * 2;
296 data = g_malloc (size);
297 in_buffer = buffer_data_size (buffer);
300 buffer->data + buffer->start,
302 g_free (buffer->data);
304 buffer->end -= buffer->start;
309 /* Ensures that the buffer can fit at_least_size bytes,
310 * *including* the current in-buffer data */
312 buffer_ensure_space (Buffer *buffer,
315 gsize in_buffer, left_to_fill;
317 in_buffer = buffer_data_size (buffer);
319 if (in_buffer >= at_least_size)
322 left_to_fill = buffer_tailspace (buffer);
324 if (in_buffer + left_to_fill >= at_least_size)
326 /* We fit in remaining space at end */
327 /* If the copy is small, compact now anyway so we can fill more */
329 compact_buffer (buffer);
331 else if (buffer->size >= at_least_size)
333 /* We fit, but only if we compact */
334 compact_buffer (buffer);
338 /* Need to grow buffer */
339 while (buffer->size < at_least_size)
340 grow_buffer (buffer);
345 fill_input_buffer (GConverterInputStream *stream,
348 GCancellable *cancellable,
351 GConverterInputStreamPrivate *priv;
352 GInputStream *base_stream;
357 buffer_ensure_space (&priv->input_buffer, at_least_size);
359 base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream;
360 nread = g_pollable_stream_read (base_stream,
361 priv->input_buffer.data + priv->input_buffer.end,
362 buffer_tailspace (&priv->input_buffer),
369 priv->input_buffer.end += nread;
370 priv->need_input = FALSE;
378 read_internal (GInputStream *stream,
382 GCancellable *cancellable,
385 GConverterInputStream *cstream;
386 GConverterInputStreamPrivate *priv;
387 gsize available, total_bytes_read;
389 GConverterResult res;
395 cstream = G_CONVERTER_INPUT_STREAM (stream);
396 priv = cstream->priv;
398 available = buffer_data_size (&priv->converted_buffer);
403 /* Converted data available, return that */
404 buffer_read (&priv->converted_buffer, buffer, count);
408 /* Full request not available, read all currently available and request
409 refill/conversion for more */
411 buffer_read (&priv->converted_buffer, buffer, available);
413 total_bytes_read = available;
414 buffer = (char *) buffer + available;
417 /* If there is no data to convert, and no pre-converted data,
418 do some i/o for more input */
419 if (buffer_data_size (&priv->input_buffer) == 0 &&
420 total_bytes_read == 0 &&
423 nread = fill_input_buffer (cstream, count, blocking, cancellable, error);
427 priv->at_input_end = TRUE;
430 /* First try to convert any available data (or state) directly to the user buffer: */
434 res = g_converter_convert (priv->converter,
435 buffer_data (&priv->input_buffer),
436 buffer_data_size (&priv->input_buffer),
438 priv->at_input_end ? G_CONVERTER_INPUT_AT_END : 0,
442 if (res != G_CONVERTER_ERROR)
444 total_bytes_read += bytes_written;
445 buffer_consumed (&priv->input_buffer, bytes_read);
446 if (res == G_CONVERTER_FINISHED)
447 priv->finished = TRUE; /* We're done converting */
449 else if (total_bytes_read == 0 &&
450 !g_error_matches (my_error,
452 G_IO_ERROR_PARTIAL_INPUT) &&
453 !g_error_matches (my_error,
455 G_IO_ERROR_NO_SPACE))
457 /* No previously read data and no "special" error, return error */
458 g_propagate_error (error, my_error);
462 g_error_free (my_error);
465 /* We had some pre-converted data and/or we converted directly to the
467 if (total_bytes_read > 0)
468 return total_bytes_read;
470 /* If there is no more to convert, return EOF */
473 g_assert (buffer_data_size (&priv->converted_buffer) == 0);
477 /* There was "complexity" in the straight-to-buffer conversion,
478 * convert to our own buffer and write from that.
479 * At this point we didn't produce any data into @buffer.
482 /* Ensure we have *some* initial target space */
483 buffer_ensure_space (&priv->converted_buffer, count);
487 g_assert (!priv->finished);
489 /* Try to convert to our buffer */
491 res = g_converter_convert (priv->converter,
492 buffer_data (&priv->input_buffer),
493 buffer_data_size (&priv->input_buffer),
494 buffer_data (&priv->converted_buffer),
495 buffer_tailspace (&priv->converted_buffer),
496 priv->at_input_end ? G_CONVERTER_INPUT_AT_END : 0,
500 if (res != G_CONVERTER_ERROR)
502 priv->converted_buffer.end += bytes_written;
503 buffer_consumed (&priv->input_buffer, bytes_read);
505 /* Maybe we consumed without producing any output */
506 if (buffer_data_size (&priv->converted_buffer) == 0 && res != G_CONVERTER_FINISHED)
507 continue; /* Convert more */
509 if (res == G_CONVERTER_FINISHED)
510 priv->finished = TRUE;
512 total_bytes_read = MIN (count, buffer_data_size (&priv->converted_buffer));
513 buffer_read (&priv->converted_buffer, buffer, total_bytes_read);
515 g_assert (priv->finished || total_bytes_read > 0);
517 return total_bytes_read;
520 /* There was some kind of error filling our buffer */
522 if (g_error_matches (my_error,
524 G_IO_ERROR_PARTIAL_INPUT) &&
529 nread = fill_input_buffer (cstream,
530 buffer_data_size (&priv->input_buffer) + 4096,
536 /* Can't read any more data, return that error */
537 g_error_free (my_error);
538 g_propagate_error (error, my_error2);
539 priv->need_input = TRUE;
544 /* End of file, try INPUT_AT_END */
545 priv->at_input_end = TRUE;
547 g_error_free (my_error);
551 if (g_error_matches (my_error,
553 G_IO_ERROR_NO_SPACE))
555 /* Need more destination space, grow it
556 * Note: if we actually grow the buffer (as opposed to compacting it),
557 * this will double the size, not just add one byte. */
558 buffer_ensure_space (&priv->converted_buffer,
559 priv->converted_buffer.size + 1);
560 g_error_free (my_error);
564 /* Any other random error, return it */
565 g_propagate_error (error, my_error);
569 g_assert_not_reached ();
573 g_converter_input_stream_read (GInputStream *stream,
576 GCancellable *cancellable,
579 return read_internal (stream, buffer, count, TRUE, cancellable, error);
583 g_converter_input_stream_can_poll (GPollableInputStream *stream)
585 GInputStream *base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream;
587 return (G_IS_POLLABLE_INPUT_STREAM (base_stream) &&
588 g_pollable_input_stream_can_poll (G_POLLABLE_INPUT_STREAM (base_stream)));
592 g_converter_input_stream_is_readable (GPollableInputStream *stream)
594 GInputStream *base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream;
595 GConverterInputStream *cstream = G_CONVERTER_INPUT_STREAM (stream);
597 if (buffer_data_size (&cstream->priv->converted_buffer))
599 else if (buffer_data_size (&cstream->priv->input_buffer) &&
600 !cstream->priv->need_input)
603 return g_pollable_input_stream_is_readable (G_POLLABLE_INPUT_STREAM (base_stream));
607 g_converter_input_stream_read_nonblocking (GPollableInputStream *stream,
612 return read_internal (G_INPUT_STREAM (stream), buffer, count,
617 g_converter_input_stream_create_source (GPollableInputStream *stream,
618 GCancellable *cancellable)
620 GInputStream *base_stream = G_FILTER_INPUT_STREAM (stream)->base_stream;
621 GSource *base_source, *pollable_source;
623 if (g_pollable_input_stream_is_readable (stream))
624 base_source = g_timeout_source_new (0);
626 base_source = g_pollable_input_stream_create_source (G_POLLABLE_INPUT_STREAM (base_stream), NULL);
628 pollable_source = g_pollable_source_new_full (stream, base_source,
630 g_source_unref (base_source);
632 return pollable_source;
637 * g_converter_input_stream_get_converter:
638 * @converter_stream: a #GConverterInputStream
640 * Gets the #GConverter that is used by @converter_stream.
642 * Returns: (transfer none): the converter of the converter input stream
647 g_converter_input_stream_get_converter (GConverterInputStream *converter_stream)
649 return converter_stream->priv->converter;