1 /* GIO - GLib Input, Output and Streaming Library
2  *
3  * Copyright (C) 2006-2007 Red Hat, Inc.
4  *
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 2.1 of the License, or (at your option) any later version.
9  *
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.
14  *
15  * You should have received a copy of the GNU Lesser General
16  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
17  *
18  * Author: Alexander Larsson <alexl@redhat.com>
19  */
20 
21 #include "config.h"
22 #include <string.h>
23 #include "gdataoutputstream.h"
24 #include "gseekable.h"
25 #include "gioenumtypes.h"
26 #include "gioerror.h"
27 #include "glibintl.h"
28 
29 
30 /**
31  * SECTION:gdataoutputstream
32  * @short_description: Data Output Stream
33  * @include: gio/gio.h
34  * @see_also: #GOutputStream
35  *
36  * Data output stream implements #GOutputStream and includes functions for
37  * writing data directly to an output stream.
38  *
39  **/
40 
41 
42 
43 struct _GDataOutputStreamPrivate {
44   GDataStreamByteOrder byte_order;
45 };
46 
47 enum {
48   PROP_0,
49   PROP_BYTE_ORDER
50 };
51 
52 static void g_data_output_stream_set_property (GObject      *object,
53 					       guint         prop_id,
54 					       const GValue *value,
55 					       GParamSpec   *pspec);
56 static void g_data_output_stream_get_property (GObject      *object,
57 					       guint         prop_id,
58 					       GValue       *value,
59 					       GParamSpec   *pspec);
60 
61 static void     g_data_output_stream_seekable_iface_init (GSeekableIface  *iface);
62 static goffset  g_data_output_stream_tell                (GSeekable       *seekable);
63 static gboolean g_data_output_stream_can_seek            (GSeekable       *seekable);
64 static gboolean g_data_output_stream_seek                (GSeekable       *seekable,
65 							  goffset          offset,
66 							  GSeekType        type,
67 							  GCancellable    *cancellable,
68 							  GError         **error);
69 static gboolean g_data_output_stream_can_truncate        (GSeekable       *seekable);
70 static gboolean g_data_output_stream_truncate            (GSeekable       *seekable,
71 							  goffset          offset,
72 							  GCancellable    *cancellable,
73 							  GError         **error);
74 
75 G_DEFINE_TYPE_WITH_CODE (GDataOutputStream,
76 			 g_data_output_stream,
77 			 G_TYPE_FILTER_OUTPUT_STREAM,
78                          G_ADD_PRIVATE (GDataOutputStream)
79 			 G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE,
80 						g_data_output_stream_seekable_iface_init))
81 
82 
83 static void
84 g_data_output_stream_class_init (GDataOutputStreamClass *klass)
85 {
86   GObjectClass *object_class;
87 
88   object_class = G_OBJECT_CLASS (klass);
89   object_class->get_property = g_data_output_stream_get_property;
90   object_class->set_property = g_data_output_stream_set_property;
91 
92   /**
93    * GDataOutputStream:byte-order:
94    *
95    * Determines the byte ordering that is used when writing
96    * multi-byte entities (such as integers) to the stream.
97    */
98   g_object_class_install_property (object_class,
99                                    PROP_BYTE_ORDER,
100                                    g_param_spec_enum ("byte-order",
101                                                       P_("Byte order"),
102                                                       P_("The byte order"),
103                                                       G_TYPE_DATA_STREAM_BYTE_ORDER,
104                                                       G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN,
105                                                       G_PARAM_READWRITE|G_PARAM_STATIC_NAME|G_PARAM_STATIC_BLURB));
106 
107 }
108 
109 static void
110 g_data_output_stream_set_property (GObject     *object,
111 				  guint         prop_id,
112 				  const GValue *value,
113 				  GParamSpec   *pspec)
114 {
115   GDataOutputStream *dstream;
116 
117   dstream = G_DATA_OUTPUT_STREAM (object);
118 
119   switch (prop_id)
120     {
121     case PROP_BYTE_ORDER:
122       g_data_output_stream_set_byte_order (dstream, g_value_get_enum (value));
123       break;
124 
125     default:
126       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
127       break;
128     }
129 }
130 
131 static void
132 g_data_output_stream_get_property (GObject    *object,
133 				   guint       prop_id,
134 				   GValue     *value,
135 				   GParamSpec *pspec)
136 {
137   GDataOutputStreamPrivate *priv;
138   GDataOutputStream        *dstream;
139 
140   dstream = G_DATA_OUTPUT_STREAM (object);
141   priv = dstream->priv;
142 
143   switch (prop_id)
144     {
145     case PROP_BYTE_ORDER:
146       g_value_set_enum (value, priv->byte_order);
147       break;
148 
149     default:
150       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
151       break;
152     }
153 }
154 
155 static void
156 g_data_output_stream_init (GDataOutputStream *stream)
157 {
158   stream->priv = g_data_output_stream_get_instance_private (stream);
159   stream->priv->byte_order = G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN;
160 }
161 
162 static void
163 g_data_output_stream_seekable_iface_init (GSeekableIface *iface)
164 {
165   iface->tell         = g_data_output_stream_tell;
166   iface->can_seek     = g_data_output_stream_can_seek;
167   iface->seek         = g_data_output_stream_seek;
168   iface->can_truncate = g_data_output_stream_can_truncate;
169   iface->truncate_fn  = g_data_output_stream_truncate;
170 }
171 
172 /**
173  * g_data_output_stream_new:
174  * @base_stream: a #GOutputStream.
175  *
176  * Creates a new data output stream for @base_stream.
177  *
178  * Returns: #GDataOutputStream.
179  **/
180 GDataOutputStream *
181 g_data_output_stream_new (GOutputStream *base_stream)
182 {
183   GDataOutputStream *stream;
184 
185   g_return_val_if_fail (G_IS_OUTPUT_STREAM (base_stream), NULL);
186 
187   stream = g_object_new (G_TYPE_DATA_OUTPUT_STREAM,
188                          "base-stream", base_stream,
189                          NULL);
190 
191   return stream;
192 }
193 
194 /**
195  * g_data_output_stream_set_byte_order:
196  * @stream: a #GDataOutputStream.
197  * @order: a %GDataStreamByteOrder.
198  *
199  * Sets the byte order of the data output stream to @order.
200  **/
201 void
202 g_data_output_stream_set_byte_order (GDataOutputStream    *stream,
203                                      GDataStreamByteOrder  order)
204 {
205   GDataOutputStreamPrivate *priv;
206   g_return_if_fail (G_IS_DATA_OUTPUT_STREAM (stream));
207   priv = stream->priv;
208   if (priv->byte_order != order)
209     {
210       priv->byte_order = order;
211       g_object_notify (G_OBJECT (stream), "byte-order");
212     }
213 }
214 
215 /**
216  * g_data_output_stream_get_byte_order:
217  * @stream: a #GDataOutputStream.
218  *
219  * Gets the byte order for the stream.
220  *
221  * Returns: the #GDataStreamByteOrder for the @stream.
222  **/
223 GDataStreamByteOrder
224 g_data_output_stream_get_byte_order (GDataOutputStream *stream)
225 {
226   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN);
227 
228   return stream->priv->byte_order;
229 }
230 
231 /**
232  * g_data_output_stream_put_byte:
233  * @stream: a #GDataOutputStream.
234  * @data: a #guchar.
235  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
236  * @error: a #GError, %NULL to ignore.
237  *
238  * Puts a byte into the output stream.
239  *
240  * Returns: %TRUE if @data was successfully added to the @stream.
241  **/
242 gboolean
243 g_data_output_stream_put_byte (GDataOutputStream  *stream,
244 			       guchar              data,
245 			       GCancellable       *cancellable,
246 			       GError            **error)
247 {
248   gsize bytes_written;
249 
250   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
251 
252   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
253 				    &data, 1,
254 				    &bytes_written,
255 				    cancellable, error);
256 }
257 
258 /**
259  * g_data_output_stream_put_int16:
260  * @stream: a #GDataOutputStream.
261  * @data: a #gint16.
262  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
263  * @error: a #GError, %NULL to ignore.
264  *
265  * Puts a signed 16-bit integer into the output stream.
266  *
267  * Returns: %TRUE if @data was successfully added to the @stream.
268  **/
269 gboolean
270 g_data_output_stream_put_int16 (GDataOutputStream  *stream,
271 				gint16              data,
272 				GCancellable       *cancellable,
273 				GError            **error)
274 {
275   gsize bytes_written;
276 
277   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
278 
279   switch (stream->priv->byte_order)
280     {
281     case G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN:
282       data = GINT16_TO_BE (data);
283       break;
284     case G_DATA_STREAM_BYTE_ORDER_LITTLE_ENDIAN:
285       data = GINT16_TO_LE (data);
286       break;
287     case G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN:
288     default:
289       break;
290     }
291 
292   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
293 				    &data, 2,
294 				    &bytes_written,
295 				    cancellable, error);
296 }
297 
298 /**
299  * g_data_output_stream_put_uint16:
300  * @stream: a #GDataOutputStream.
301  * @data: a #guint16.
302  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
303  * @error: a #GError, %NULL to ignore.
304  *
305  * Puts an unsigned 16-bit integer into the output stream.
306  *
307  * Returns: %TRUE if @data was successfully added to the @stream.
308  **/
309 gboolean
310 g_data_output_stream_put_uint16 (GDataOutputStream  *stream,
311 				 guint16             data,
312 				 GCancellable       *cancellable,
313 				 GError            **error)
314 {
315   gsize bytes_written;
316 
317   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
318 
319   switch (stream->priv->byte_order)
320     {
321     case G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN:
322       data = GUINT16_TO_BE (data);
323       break;
324     case G_DATA_STREAM_BYTE_ORDER_LITTLE_ENDIAN:
325       data = GUINT16_TO_LE (data);
326       break;
327     case G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN:
328     default:
329       break;
330     }
331 
332   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
333 				    &data, 2,
334 				    &bytes_written,
335 				    cancellable, error);
336 }
337 
338 /**
339  * g_data_output_stream_put_int32:
340  * @stream: a #GDataOutputStream.
341  * @data: a #gint32.
342  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
343  * @error: a #GError, %NULL to ignore.
344  *
345  * Puts a signed 32-bit integer into the output stream.
346  *
347  * Returns: %TRUE if @data was successfully added to the @stream.
348  **/
349 gboolean
350 g_data_output_stream_put_int32 (GDataOutputStream  *stream,
351 				gint32              data,
352 				GCancellable       *cancellable,
353 				GError            **error)
354 {
355   gsize bytes_written;
356 
357   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
358 
359   switch (stream->priv->byte_order)
360     {
361     case G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN:
362       data = GINT32_TO_BE (data);
363       break;
364     case G_DATA_STREAM_BYTE_ORDER_LITTLE_ENDIAN:
365       data = GINT32_TO_LE (data);
366       break;
367     case G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN:
368     default:
369       break;
370     }
371 
372   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
373 				    &data, 4,
374 				    &bytes_written,
375 				    cancellable, error);
376 }
377 
378 /**
379  * g_data_output_stream_put_uint32:
380  * @stream: a #GDataOutputStream.
381  * @data: a #guint32.
382  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
383  * @error: a #GError, %NULL to ignore.
384  *
385  * Puts an unsigned 32-bit integer into the stream.
386  *
387  * Returns: %TRUE if @data was successfully added to the @stream.
388  **/
389 gboolean
390 g_data_output_stream_put_uint32 (GDataOutputStream  *stream,
391 				 guint32             data,
392 				 GCancellable       *cancellable,
393 				 GError            **error)
394 {
395   gsize bytes_written;
396 
397   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
398 
399   switch (stream->priv->byte_order)
400     {
401     case G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN:
402       data = GUINT32_TO_BE (data);
403       break;
404     case G_DATA_STREAM_BYTE_ORDER_LITTLE_ENDIAN:
405       data = GUINT32_TO_LE (data);
406       break;
407     case G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN:
408     default:
409       break;
410     }
411 
412   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
413 				    &data, 4,
414 				    &bytes_written,
415 				    cancellable, error);
416 }
417 
418 /**
419  * g_data_output_stream_put_int64:
420  * @stream: a #GDataOutputStream.
421  * @data: a #gint64.
422  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
423  * @error: a #GError, %NULL to ignore.
424  *
425  * Puts a signed 64-bit integer into the stream.
426  *
427  * Returns: %TRUE if @data was successfully added to the @stream.
428  **/
429 gboolean
430 g_data_output_stream_put_int64 (GDataOutputStream  *stream,
431 				gint64              data,
432 				GCancellable       *cancellable,
433 				GError            **error)
434 {
435   gsize bytes_written;
436 
437   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
438 
439   switch (stream->priv->byte_order)
440     {
441     case G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN:
442       data = GINT64_TO_BE (data);
443       break;
444     case G_DATA_STREAM_BYTE_ORDER_LITTLE_ENDIAN:
445       data = GINT64_TO_LE (data);
446       break;
447     case G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN:
448     default:
449       break;
450     }
451 
452   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
453 				    &data, 8,
454 				    &bytes_written,
455 				    cancellable, error);
456 }
457 
458 /**
459  * g_data_output_stream_put_uint64:
460  * @stream: a #GDataOutputStream.
461  * @data: a #guint64.
462  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
463  * @error: a #GError, %NULL to ignore.
464  *
465  * Puts an unsigned 64-bit integer into the stream.
466  *
467  * Returns: %TRUE if @data was successfully added to the @stream.
468  **/
469 gboolean
470 g_data_output_stream_put_uint64 (GDataOutputStream  *stream,
471 				 guint64             data,
472 				 GCancellable       *cancellable,
473 				 GError            **error)
474 {
475   gsize bytes_written;
476 
477   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
478 
479   switch (stream->priv->byte_order)
480     {
481     case G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN:
482       data = GUINT64_TO_BE (data);
483       break;
484     case G_DATA_STREAM_BYTE_ORDER_LITTLE_ENDIAN:
485       data = GUINT64_TO_LE (data);
486       break;
487     case G_DATA_STREAM_BYTE_ORDER_HOST_ENDIAN:
488     default:
489       break;
490     }
491 
492   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
493 				    &data, 8,
494 				    &bytes_written,
495 				    cancellable, error);
496 }
497 
498 /**
499  * g_data_output_stream_put_string:
500  * @stream: a #GDataOutputStream.
501  * @str: a string.
502  * @cancellable: (nullable): optional #GCancellable object, %NULL to ignore.
503  * @error: a #GError, %NULL to ignore.
504  *
505  * Puts a string into the output stream.
506  *
507  * Returns: %TRUE if @string was successfully added to the @stream.
508  **/
509 gboolean
510 g_data_output_stream_put_string (GDataOutputStream  *stream,
511 				 const char         *str,
512 				 GCancellable       *cancellable,
513 				 GError            **error)
514 {
515   gsize bytes_written;
516 
517   g_return_val_if_fail (G_IS_DATA_OUTPUT_STREAM (stream), FALSE);
518   g_return_val_if_fail (str != NULL, FALSE);
519 
520   return g_output_stream_write_all (G_OUTPUT_STREAM (stream),
521 				    str, strlen (str),
522 				    &bytes_written,
523 				    cancellable, error);
524 }
525 
526 static goffset
527 g_data_output_stream_tell (GSeekable *seekable)
528 {
529   GOutputStream *base_stream;
530   GSeekable *base_stream_seekable;
531 
532   base_stream = G_FILTER_OUTPUT_STREAM (seekable)->base_stream;
533   if (!G_IS_SEEKABLE (base_stream))
534     return 0;
535   base_stream_seekable = G_SEEKABLE (base_stream);
536   return g_seekable_tell (base_stream_seekable);
537 }
538 
539 static gboolean
540 g_data_output_stream_can_seek (GSeekable *seekable)
541 {
542   GOutputStream *base_stream;
543 
544   base_stream = G_FILTER_OUTPUT_STREAM (seekable)->base_stream;
545   return G_IS_SEEKABLE (base_stream) && g_seekable_can_seek (G_SEEKABLE (base_stream));
546 }
547 
548 static gboolean
549 g_data_output_stream_seek (GSeekable     *seekable,
550 			   goffset        offset,
551 			   GSeekType      type,
552 			   GCancellable  *cancellable,
553 			   GError       **error)
554 {
555   GOutputStream *base_stream;
556   GSeekable *base_stream_seekable;
557 
558   base_stream = G_FILTER_OUTPUT_STREAM (seekable)->base_stream;
559   if (!G_IS_SEEKABLE (base_stream))
560     {
561       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
562                            _("Seek not supported on base stream"));
563       return FALSE;
564     }
565 
566   base_stream_seekable = G_SEEKABLE (base_stream);
567   return g_seekable_seek (base_stream_seekable, offset, type, cancellable, error);
568 }
569 
570 static gboolean
571 g_data_output_stream_can_truncate (GSeekable *seekable)
572 {
573   GOutputStream *base_stream;
574 
575   base_stream = G_FILTER_OUTPUT_STREAM (seekable)->base_stream;
576   return G_IS_SEEKABLE (base_stream) && g_seekable_can_truncate (G_SEEKABLE (base_stream));
577 }
578 
579 static gboolean
580 g_data_output_stream_truncate (GSeekable     *seekable,
581 				   goffset        offset,
582 				   GCancellable  *cancellable,
583 				   GError       **error)
584 {
585   GOutputStream *base_stream;
586   GSeekable *base_stream_seekable;
587 
588   base_stream = G_FILTER_OUTPUT_STREAM (seekable)->base_stream;
589   if (!G_IS_SEEKABLE (base_stream))
590     {
591       g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
592                            _("Truncate not supported on base stream"));
593       return FALSE;
594     }
595 
596   base_stream_seekable = G_SEEKABLE (base_stream);
597   return g_seekable_truncate (base_stream_seekable, offset, cancellable, error);
598 }
599