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 | * Authors: |
19 | * Christian Kellner <gicmo@gnome.org> |
20 | * Krzysztof KosiĆski <tweenk.pl@gmail.com> |
21 | */ |
22 | |
23 | #include "config.h" |
24 | #include "gmemoryoutputstream.h" |
25 | #include "goutputstream.h" |
26 | #include "gpollableoutputstream.h" |
27 | #include "gseekable.h" |
28 | #include "gtask.h" |
29 | #include "gioerror.h" |
30 | #include "string.h" |
31 | #include "glibintl.h" |
32 | |
33 | |
34 | /** |
35 | * SECTION:gmemoryoutputstream |
36 | * @short_description: Streaming output operations on memory chunks |
37 | * @include: gio/gio.h |
38 | * @see_also: #GMemoryInputStream |
39 | * |
40 | * #GMemoryOutputStream is a class for using arbitrary |
41 | * memory chunks as output for GIO streaming output operations. |
42 | * |
43 | * As of GLib 2.34, #GMemoryOutputStream trivially implements |
44 | * #GPollableOutputStream: it always polls as ready. |
45 | */ |
46 | |
47 | #define MIN_ARRAY_SIZE 16 |
48 | |
49 | enum { |
50 | PROP_0, |
51 | PROP_DATA, |
52 | PROP_SIZE, |
53 | PROP_DATA_SIZE, |
54 | PROP_REALLOC_FUNCTION, |
55 | PROP_DESTROY_FUNCTION |
56 | }; |
57 | |
58 | struct _GMemoryOutputStreamPrivate |
59 | { |
60 | gpointer data; /* Write buffer */ |
61 | gsize len; /* Current length of the data buffer. Can change with resizing. */ |
62 | gsize valid_len; /* The part of data that has been written to */ |
63 | gsize pos; /* Current position in the stream. Distinct from valid_len, |
64 | because the stream is seekable. */ |
65 | |
66 | GReallocFunc realloc_fn; |
67 | GDestroyNotify destroy; |
68 | }; |
69 | |
70 | static void g_memory_output_stream_set_property (GObject *object, |
71 | guint prop_id, |
72 | const GValue *value, |
73 | GParamSpec *pspec); |
74 | static void g_memory_output_stream_get_property (GObject *object, |
75 | guint prop_id, |
76 | GValue *value, |
77 | GParamSpec *pspec); |
78 | static void g_memory_output_stream_finalize (GObject *object); |
79 | |
80 | static gssize g_memory_output_stream_write (GOutputStream *stream, |
81 | const void *buffer, |
82 | gsize count, |
83 | GCancellable *cancellable, |
84 | GError **error); |
85 | |
86 | static gboolean g_memory_output_stream_close (GOutputStream *stream, |
87 | GCancellable *cancellable, |
88 | GError **error); |
89 | |
90 | static void g_memory_output_stream_close_async (GOutputStream *stream, |
91 | int io_priority, |
92 | GCancellable *cancellable, |
93 | GAsyncReadyCallback callback, |
94 | gpointer data); |
95 | static gboolean g_memory_output_stream_close_finish (GOutputStream *stream, |
96 | GAsyncResult *result, |
97 | GError **error); |
98 | |
99 | static void g_memory_output_stream_seekable_iface_init (GSeekableIface *iface); |
100 | static goffset g_memory_output_stream_tell (GSeekable *seekable); |
101 | static gboolean g_memory_output_stream_can_seek (GSeekable *seekable); |
102 | static gboolean g_memory_output_stream_seek (GSeekable *seekable, |
103 | goffset offset, |
104 | GSeekType type, |
105 | GCancellable *cancellable, |
106 | GError **error); |
107 | static gboolean g_memory_output_stream_can_truncate (GSeekable *seekable); |
108 | static gboolean g_memory_output_stream_truncate (GSeekable *seekable, |
109 | goffset offset, |
110 | GCancellable *cancellable, |
111 | GError **error); |
112 | |
113 | static gboolean g_memory_output_stream_is_writable (GPollableOutputStream *stream); |
114 | static GSource *g_memory_output_stream_create_source (GPollableOutputStream *stream, |
115 | GCancellable *cancellable); |
116 | |
117 | static void g_memory_output_stream_pollable_iface_init (GPollableOutputStreamInterface *iface); |
118 | |
119 | G_DEFINE_TYPE_WITH_CODE (GMemoryOutputStream, g_memory_output_stream, G_TYPE_OUTPUT_STREAM, |
120 | G_ADD_PRIVATE (GMemoryOutputStream) |
121 | G_IMPLEMENT_INTERFACE (G_TYPE_SEEKABLE, |
122 | g_memory_output_stream_seekable_iface_init); |
123 | G_IMPLEMENT_INTERFACE (G_TYPE_POLLABLE_OUTPUT_STREAM, |
124 | g_memory_output_stream_pollable_iface_init)) |
125 | |
126 | |
127 | static void |
128 | g_memory_output_stream_class_init (GMemoryOutputStreamClass *klass) |
129 | { |
130 | GOutputStreamClass *ostream_class; |
131 | GObjectClass *gobject_class; |
132 | |
133 | gobject_class = G_OBJECT_CLASS (klass); |
134 | gobject_class->set_property = g_memory_output_stream_set_property; |
135 | gobject_class->get_property = g_memory_output_stream_get_property; |
136 | gobject_class->finalize = g_memory_output_stream_finalize; |
137 | |
138 | ostream_class = G_OUTPUT_STREAM_CLASS (klass); |
139 | |
140 | ostream_class->write_fn = g_memory_output_stream_write; |
141 | ostream_class->close_fn = g_memory_output_stream_close; |
142 | ostream_class->close_async = g_memory_output_stream_close_async; |
143 | ostream_class->close_finish = g_memory_output_stream_close_finish; |
144 | |
145 | /** |
146 | * GMemoryOutputStream:data: |
147 | * |
148 | * Pointer to buffer where data will be written. |
149 | * |
150 | * Since: 2.24 |
151 | **/ |
152 | g_object_class_install_property (oclass: gobject_class, |
153 | property_id: PROP_DATA, |
154 | pspec: g_param_spec_pointer (name: "data" , |
155 | P_("Data Buffer" ), |
156 | P_("Pointer to buffer where data will be written." ), |
157 | flags: G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | |
158 | G_PARAM_STATIC_STRINGS)); |
159 | |
160 | /** |
161 | * GMemoryOutputStream:size: |
162 | * |
163 | * Current size of the data buffer. |
164 | * |
165 | * Since: 2.24 |
166 | **/ |
167 | g_object_class_install_property (oclass: gobject_class, |
168 | property_id: PROP_SIZE, |
169 | pspec: g_param_spec_ulong (name: "size" , |
170 | P_("Data Buffer Size" ), |
171 | P_("Current size of the data buffer." ), |
172 | minimum: 0, G_MAXULONG, default_value: 0, |
173 | flags: G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | |
174 | G_PARAM_STATIC_STRINGS)); |
175 | |
176 | /** |
177 | * GMemoryOutputStream:data-size: |
178 | * |
179 | * Size of data written to the buffer. |
180 | * |
181 | * Since: 2.24 |
182 | **/ |
183 | g_object_class_install_property (oclass: gobject_class, |
184 | property_id: PROP_DATA_SIZE, |
185 | pspec: g_param_spec_ulong (name: "data-size" , |
186 | P_("Data Size" ), |
187 | P_("Size of data written to the buffer." ), |
188 | minimum: 0, G_MAXULONG, default_value: 0, |
189 | flags: G_PARAM_READABLE | |
190 | G_PARAM_STATIC_STRINGS)); |
191 | |
192 | /** |
193 | * GMemoryOutputStream:realloc-function: (skip) |
194 | * |
195 | * Function with realloc semantics called to enlarge the buffer. |
196 | * |
197 | * Since: 2.24 |
198 | **/ |
199 | g_object_class_install_property (oclass: gobject_class, |
200 | property_id: PROP_REALLOC_FUNCTION, |
201 | pspec: g_param_spec_pointer (name: "realloc-function" , |
202 | P_("Memory Reallocation Function" ), |
203 | P_("Function with realloc semantics called to enlarge the buffer." ), |
204 | flags: G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | |
205 | G_PARAM_STATIC_STRINGS)); |
206 | |
207 | /** |
208 | * GMemoryOutputStream:destroy-function: (skip) |
209 | * |
210 | * Function called with the buffer as argument when the stream is destroyed. |
211 | * |
212 | * Since: 2.24 |
213 | **/ |
214 | g_object_class_install_property (oclass: gobject_class, |
215 | property_id: PROP_DESTROY_FUNCTION, |
216 | pspec: g_param_spec_pointer (name: "destroy-function" , |
217 | P_("Destroy Notification Function" ), |
218 | P_("Function called with the buffer as argument when the stream is destroyed." ), |
219 | flags: G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | |
220 | G_PARAM_STATIC_STRINGS)); |
221 | } |
222 | |
223 | static void |
224 | g_memory_output_stream_pollable_iface_init (GPollableOutputStreamInterface *iface) |
225 | { |
226 | iface->is_writable = g_memory_output_stream_is_writable; |
227 | iface->create_source = g_memory_output_stream_create_source; |
228 | } |
229 | |
230 | static void |
231 | g_memory_output_stream_set_property (GObject *object, |
232 | guint prop_id, |
233 | const GValue *value, |
234 | GParamSpec *pspec) |
235 | { |
236 | GMemoryOutputStream *stream; |
237 | GMemoryOutputStreamPrivate *priv; |
238 | |
239 | stream = G_MEMORY_OUTPUT_STREAM (object); |
240 | priv = stream->priv; |
241 | |
242 | switch (prop_id) |
243 | { |
244 | case PROP_DATA: |
245 | priv->data = g_value_get_pointer (value); |
246 | break; |
247 | case PROP_SIZE: |
248 | priv->len = g_value_get_ulong (value); |
249 | break; |
250 | case PROP_REALLOC_FUNCTION: |
251 | priv->realloc_fn = g_value_get_pointer (value); |
252 | break; |
253 | case PROP_DESTROY_FUNCTION: |
254 | priv->destroy = g_value_get_pointer (value); |
255 | break; |
256 | default: |
257 | G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); |
258 | break; |
259 | } |
260 | } |
261 | |
262 | static void |
263 | g_memory_output_stream_get_property (GObject *object, |
264 | guint prop_id, |
265 | GValue *value, |
266 | GParamSpec *pspec) |
267 | { |
268 | GMemoryOutputStream *stream; |
269 | GMemoryOutputStreamPrivate *priv; |
270 | |
271 | stream = G_MEMORY_OUTPUT_STREAM (object); |
272 | priv = stream->priv; |
273 | |
274 | switch (prop_id) |
275 | { |
276 | case PROP_DATA: |
277 | g_value_set_pointer (value, v_pointer: priv->data); |
278 | break; |
279 | case PROP_SIZE: |
280 | g_value_set_ulong (value, v_ulong: priv->len); |
281 | break; |
282 | case PROP_DATA_SIZE: |
283 | g_value_set_ulong (value, v_ulong: priv->valid_len); |
284 | break; |
285 | case PROP_REALLOC_FUNCTION: |
286 | g_value_set_pointer (value, v_pointer: priv->realloc_fn); |
287 | break; |
288 | case PROP_DESTROY_FUNCTION: |
289 | g_value_set_pointer (value, v_pointer: priv->destroy); |
290 | break; |
291 | default: |
292 | G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); |
293 | break; |
294 | } |
295 | } |
296 | |
297 | static void |
298 | g_memory_output_stream_finalize (GObject *object) |
299 | { |
300 | GMemoryOutputStream *stream; |
301 | GMemoryOutputStreamPrivate *priv; |
302 | |
303 | stream = G_MEMORY_OUTPUT_STREAM (object); |
304 | priv = stream->priv; |
305 | |
306 | if (priv->destroy) |
307 | priv->destroy (priv->data); |
308 | |
309 | G_OBJECT_CLASS (g_memory_output_stream_parent_class)->finalize (object); |
310 | } |
311 | |
312 | static void |
313 | g_memory_output_stream_seekable_iface_init (GSeekableIface *iface) |
314 | { |
315 | iface->tell = g_memory_output_stream_tell; |
316 | iface->can_seek = g_memory_output_stream_can_seek; |
317 | iface->seek = g_memory_output_stream_seek; |
318 | iface->can_truncate = g_memory_output_stream_can_truncate; |
319 | iface->truncate_fn = g_memory_output_stream_truncate; |
320 | } |
321 | |
322 | |
323 | static void |
324 | g_memory_output_stream_init (GMemoryOutputStream *stream) |
325 | { |
326 | stream->priv = g_memory_output_stream_get_instance_private (self: stream); |
327 | stream->priv->pos = 0; |
328 | stream->priv->valid_len = 0; |
329 | } |
330 | |
331 | /** |
332 | * g_memory_output_stream_new: (skip) |
333 | * @data: (nullable): pointer to a chunk of memory to use, or %NULL |
334 | * @size: the size of @data |
335 | * @realloc_function: (nullable): a function with realloc() semantics (like g_realloc()) |
336 | * to be called when @data needs to be grown, or %NULL |
337 | * @destroy_function: (nullable): a function to be called on @data when the stream is |
338 | * finalized, or %NULL |
339 | * |
340 | * Creates a new #GMemoryOutputStream. |
341 | * |
342 | * In most cases this is not the function you want. See |
343 | * g_memory_output_stream_new_resizable() instead. |
344 | * |
345 | * If @data is non-%NULL, the stream will use that for its internal storage. |
346 | * |
347 | * If @realloc_fn is non-%NULL, it will be used for resizing the internal |
348 | * storage when necessary and the stream will be considered resizable. |
349 | * In that case, the stream will start out being (conceptually) empty. |
350 | * @size is used only as a hint for how big @data is. Specifically, |
351 | * seeking to the end of a newly-created stream will seek to zero, not |
352 | * @size. Seeking past the end of the stream and then writing will |
353 | * introduce a zero-filled gap. |
354 | * |
355 | * If @realloc_fn is %NULL then the stream is fixed-sized. Seeking to |
356 | * the end will seek to @size exactly. Writing past the end will give |
357 | * an 'out of space' error. Attempting to seek past the end will fail. |
358 | * Unlike the resizable case, seeking to an offset within the stream and |
359 | * writing will preserve the bytes passed in as @data before that point |
360 | * and will return them as part of g_memory_output_stream_steal_data(). |
361 | * If you intend to seek you should probably therefore ensure that @data |
362 | * is properly initialised. |
363 | * |
364 | * It is probably only meaningful to provide @data and @size in the case |
365 | * that you want a fixed-sized stream. Put another way: if @realloc_fn |
366 | * is non-%NULL then it makes most sense to give @data as %NULL and |
367 | * @size as 0 (allowing #GMemoryOutputStream to do the initial |
368 | * allocation for itself). |
369 | * |
370 | * |[<!-- language="C" --> |
371 | * // a stream that can grow |
372 | * stream = g_memory_output_stream_new (NULL, 0, realloc, free); |
373 | * |
374 | * // another stream that can grow |
375 | * stream2 = g_memory_output_stream_new (NULL, 0, g_realloc, g_free); |
376 | * |
377 | * // a fixed-size stream |
378 | * data = malloc (200); |
379 | * stream3 = g_memory_output_stream_new (data, 200, NULL, free); |
380 | * ]| |
381 | * |
382 | * Returns: A newly created #GMemoryOutputStream object. |
383 | **/ |
384 | GOutputStream * |
385 | g_memory_output_stream_new (gpointer data, |
386 | gsize size, |
387 | GReallocFunc realloc_function, |
388 | GDestroyNotify destroy_function) |
389 | { |
390 | GOutputStream *stream; |
391 | |
392 | stream = g_object_new (G_TYPE_MEMORY_OUTPUT_STREAM, |
393 | first_property_name: "data" , data, |
394 | "size" , size, |
395 | "realloc-function" , realloc_function, |
396 | "destroy-function" , destroy_function, |
397 | NULL); |
398 | |
399 | return stream; |
400 | } |
401 | |
402 | /** |
403 | * g_memory_output_stream_new_resizable: |
404 | * |
405 | * Creates a new #GMemoryOutputStream, using g_realloc() and g_free() |
406 | * for memory allocation. |
407 | * |
408 | * Since: 2.36 |
409 | */ |
410 | GOutputStream * |
411 | g_memory_output_stream_new_resizable (void) |
412 | { |
413 | return g_memory_output_stream_new (NULL, size: 0, realloc_function: g_realloc, destroy_function: g_free); |
414 | } |
415 | |
416 | /** |
417 | * g_memory_output_stream_get_data: |
418 | * @ostream: a #GMemoryOutputStream |
419 | * |
420 | * Gets any loaded data from the @ostream. |
421 | * |
422 | * Note that the returned pointer may become invalid on the next |
423 | * write or truncate operation on the stream. |
424 | * |
425 | * Returns: (transfer none): pointer to the stream's data, or %NULL if the data |
426 | * has been stolen |
427 | **/ |
428 | gpointer |
429 | g_memory_output_stream_get_data (GMemoryOutputStream *ostream) |
430 | { |
431 | g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), NULL); |
432 | |
433 | return ostream->priv->data; |
434 | } |
435 | |
436 | /** |
437 | * g_memory_output_stream_get_size: |
438 | * @ostream: a #GMemoryOutputStream |
439 | * |
440 | * Gets the size of the currently allocated data area (available from |
441 | * g_memory_output_stream_get_data()). |
442 | * |
443 | * You probably don't want to use this function on resizable streams. |
444 | * See g_memory_output_stream_get_data_size() instead. For resizable |
445 | * streams the size returned by this function is an implementation |
446 | * detail and may be change at any time in response to operations on the |
447 | * stream. |
448 | * |
449 | * If the stream is fixed-sized (ie: no realloc was passed to |
450 | * g_memory_output_stream_new()) then this is the maximum size of the |
451 | * stream and further writes will return %G_IO_ERROR_NO_SPACE. |
452 | * |
453 | * In any case, if you want the number of bytes currently written to the |
454 | * stream, use g_memory_output_stream_get_data_size(). |
455 | * |
456 | * Returns: the number of bytes allocated for the data buffer |
457 | */ |
458 | gsize |
459 | g_memory_output_stream_get_size (GMemoryOutputStream *ostream) |
460 | { |
461 | g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), 0); |
462 | |
463 | return ostream->priv->len; |
464 | } |
465 | |
466 | /** |
467 | * g_memory_output_stream_get_data_size: |
468 | * @ostream: a #GMemoryOutputStream |
469 | * |
470 | * Returns the number of bytes from the start up to including the last |
471 | * byte written in the stream that has not been truncated away. |
472 | * |
473 | * Returns: the number of bytes written to the stream |
474 | * |
475 | * Since: 2.18 |
476 | */ |
477 | gsize |
478 | g_memory_output_stream_get_data_size (GMemoryOutputStream *ostream) |
479 | { |
480 | g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), 0); |
481 | |
482 | return ostream->priv->valid_len; |
483 | } |
484 | |
485 | /** |
486 | * g_memory_output_stream_steal_data: |
487 | * @ostream: a #GMemoryOutputStream |
488 | * |
489 | * Gets any loaded data from the @ostream. Ownership of the data |
490 | * is transferred to the caller; when no longer needed it must be |
491 | * freed using the free function set in @ostream's |
492 | * #GMemoryOutputStream:destroy-function property. |
493 | * |
494 | * @ostream must be closed before calling this function. |
495 | * |
496 | * Returns: (transfer full): the stream's data, or %NULL if it has previously |
497 | * been stolen |
498 | * |
499 | * Since: 2.26 |
500 | **/ |
501 | gpointer |
502 | g_memory_output_stream_steal_data (GMemoryOutputStream *ostream) |
503 | { |
504 | gpointer data; |
505 | |
506 | g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), NULL); |
507 | g_return_val_if_fail (g_output_stream_is_closed (G_OUTPUT_STREAM (ostream)), NULL); |
508 | |
509 | data = ostream->priv->data; |
510 | ostream->priv->data = NULL; |
511 | |
512 | return data; |
513 | } |
514 | |
515 | /** |
516 | * g_memory_output_stream_steal_as_bytes: |
517 | * @ostream: a #GMemoryOutputStream |
518 | * |
519 | * Returns data from the @ostream as a #GBytes. @ostream must be |
520 | * closed before calling this function. |
521 | * |
522 | * Returns: (transfer full): the stream's data |
523 | * |
524 | * Since: 2.34 |
525 | **/ |
526 | GBytes * |
527 | g_memory_output_stream_steal_as_bytes (GMemoryOutputStream *ostream) |
528 | { |
529 | GBytes *result; |
530 | |
531 | g_return_val_if_fail (G_IS_MEMORY_OUTPUT_STREAM (ostream), NULL); |
532 | g_return_val_if_fail (g_output_stream_is_closed (G_OUTPUT_STREAM (ostream)), NULL); |
533 | |
534 | result = g_bytes_new_with_free_func (data: ostream->priv->data, |
535 | size: ostream->priv->valid_len, |
536 | free_func: ostream->priv->destroy, |
537 | user_data: ostream->priv->data); |
538 | ostream->priv->data = NULL; |
539 | |
540 | return result; |
541 | } |
542 | |
543 | static gboolean |
544 | array_resize (GMemoryOutputStream *ostream, |
545 | gsize size, |
546 | gboolean allow_partial, |
547 | GError **error) |
548 | { |
549 | GMemoryOutputStreamPrivate *priv; |
550 | gpointer data; |
551 | gsize len; |
552 | |
553 | priv = ostream->priv; |
554 | |
555 | if (priv->len == size) |
556 | return TRUE; |
557 | |
558 | if (!priv->realloc_fn) |
559 | { |
560 | if (allow_partial && |
561 | priv->pos < priv->len) |
562 | return TRUE; /* Short write */ |
563 | |
564 | g_set_error_literal (err: error, |
565 | G_IO_ERROR, |
566 | code: G_IO_ERROR_NO_SPACE, |
567 | _("Memory output stream not resizable" )); |
568 | return FALSE; |
569 | } |
570 | |
571 | len = priv->len; |
572 | data = priv->realloc_fn (priv->data, size); |
573 | |
574 | if (size > 0 && !data) |
575 | { |
576 | if (allow_partial && |
577 | priv->pos < priv->len) |
578 | return TRUE; /* Short write */ |
579 | |
580 | g_set_error_literal (err: error, |
581 | G_IO_ERROR, |
582 | code: G_IO_ERROR_NO_SPACE, |
583 | _("Failed to resize memory output stream" )); |
584 | return FALSE; |
585 | } |
586 | |
587 | if (size > len) |
588 | memset (s: (guint8 *)data + len, c: 0, n: size - len); |
589 | |
590 | priv->data = data; |
591 | priv->len = size; |
592 | |
593 | if (priv->len < priv->valid_len) |
594 | priv->valid_len = priv->len; |
595 | |
596 | return TRUE; |
597 | } |
598 | |
599 | static gsize |
600 | g_nearest_pow (gsize num) |
601 | { |
602 | gsize n = 1; |
603 | |
604 | while (n < num && n > 0) |
605 | n <<= 1; |
606 | |
607 | return n; |
608 | } |
609 | |
610 | static gssize |
611 | g_memory_output_stream_write (GOutputStream *stream, |
612 | const void *buffer, |
613 | gsize count, |
614 | GCancellable *cancellable, |
615 | GError **error) |
616 | { |
617 | GMemoryOutputStream *ostream; |
618 | GMemoryOutputStreamPrivate *priv; |
619 | guint8 *dest; |
620 | gsize new_size; |
621 | |
622 | ostream = G_MEMORY_OUTPUT_STREAM (stream); |
623 | priv = ostream->priv; |
624 | |
625 | if (count == 0) |
626 | return 0; |
627 | |
628 | /* Check for address space overflow, but only if the buffer is resizable. |
629 | Otherwise we just do a short write and don't worry. */ |
630 | if (priv->realloc_fn && priv->pos + count < priv->pos) |
631 | goto overflow; |
632 | |
633 | if (priv->pos + count > priv->len) |
634 | { |
635 | /* At least enough to fit the write, rounded up for greater than |
636 | * linear growth. |
637 | * |
638 | * Assuming that we're using something like realloc(), the kernel |
639 | * will overcommit memory to us, so doubling the size each time |
640 | * will keep the number of realloc calls low without wasting too |
641 | * much memory. |
642 | */ |
643 | new_size = g_nearest_pow (num: priv->pos + count); |
644 | /* Check for overflow again. We have checked if |
645 | pos + count > G_MAXSIZE, but now check if g_nearest_pow () has |
646 | overflowed */ |
647 | if (new_size == 0) |
648 | goto overflow; |
649 | |
650 | new_size = MAX (new_size, MIN_ARRAY_SIZE); |
651 | if (!array_resize (ostream, size: new_size, TRUE, error)) |
652 | return -1; |
653 | } |
654 | |
655 | /* Make sure we handle short writes if the array_resize |
656 | only added part of the required memory */ |
657 | count = MIN (count, priv->len - priv->pos); |
658 | |
659 | dest = (guint8 *)priv->data + priv->pos; |
660 | memcpy (dest: dest, src: buffer, n: count); |
661 | priv->pos += count; |
662 | |
663 | if (priv->pos > priv->valid_len) |
664 | priv->valid_len = priv->pos; |
665 | |
666 | return count; |
667 | |
668 | overflow: |
669 | /* Overflow: buffer size would need to be bigger than G_MAXSIZE. */ |
670 | g_set_error_literal (err: error, |
671 | G_IO_ERROR, |
672 | code: G_IO_ERROR_NO_SPACE, |
673 | _("Amount of memory required to process the write is " |
674 | "larger than available address space" )); |
675 | return -1; |
676 | } |
677 | |
678 | static gboolean |
679 | g_memory_output_stream_close (GOutputStream *stream, |
680 | GCancellable *cancellable, |
681 | GError **error) |
682 | { |
683 | return TRUE; |
684 | } |
685 | |
686 | static void |
687 | g_memory_output_stream_close_async (GOutputStream *stream, |
688 | int io_priority, |
689 | GCancellable *cancellable, |
690 | GAsyncReadyCallback callback, |
691 | gpointer data) |
692 | { |
693 | GTask *task; |
694 | |
695 | task = g_task_new (source_object: stream, cancellable, callback, callback_data: data); |
696 | g_task_set_source_tag (task, g_memory_output_stream_close_async); |
697 | |
698 | /* will always return TRUE */ |
699 | g_memory_output_stream_close (stream, cancellable, NULL); |
700 | |
701 | g_task_return_boolean (task, TRUE); |
702 | g_object_unref (object: task); |
703 | } |
704 | |
705 | static gboolean |
706 | g_memory_output_stream_close_finish (GOutputStream *stream, |
707 | GAsyncResult *result, |
708 | GError **error) |
709 | { |
710 | g_return_val_if_fail (g_task_is_valid (result, stream), FALSE); |
711 | |
712 | return g_task_propagate_boolean (G_TASK (result), error); |
713 | } |
714 | |
715 | static goffset |
716 | g_memory_output_stream_tell (GSeekable *seekable) |
717 | { |
718 | GMemoryOutputStream *stream; |
719 | GMemoryOutputStreamPrivate *priv; |
720 | |
721 | stream = G_MEMORY_OUTPUT_STREAM (seekable); |
722 | priv = stream->priv; |
723 | |
724 | return priv->pos; |
725 | } |
726 | |
727 | static gboolean |
728 | g_memory_output_stream_can_seek (GSeekable *seekable) |
729 | { |
730 | return TRUE; |
731 | } |
732 | |
733 | static gboolean |
734 | g_memory_output_stream_seek (GSeekable *seekable, |
735 | goffset offset, |
736 | GSeekType type, |
737 | GCancellable *cancellable, |
738 | GError **error) |
739 | { |
740 | GMemoryOutputStream *stream; |
741 | GMemoryOutputStreamPrivate *priv; |
742 | goffset absolute; |
743 | |
744 | stream = G_MEMORY_OUTPUT_STREAM (seekable); |
745 | priv = stream->priv; |
746 | |
747 | switch (type) |
748 | { |
749 | case G_SEEK_CUR: |
750 | absolute = priv->pos + offset; |
751 | break; |
752 | |
753 | case G_SEEK_SET: |
754 | absolute = offset; |
755 | break; |
756 | |
757 | case G_SEEK_END: |
758 | /* For resizable streams, we consider the end to be the data |
759 | * length. For fixed-sized streams, we consider the end to be the |
760 | * size of the buffer. |
761 | */ |
762 | if (priv->realloc_fn) |
763 | absolute = priv->valid_len + offset; |
764 | else |
765 | absolute = priv->len + offset; |
766 | break; |
767 | |
768 | default: |
769 | g_set_error_literal (err: error, |
770 | G_IO_ERROR, |
771 | code: G_IO_ERROR_INVALID_ARGUMENT, |
772 | _("Invalid GSeekType supplied" )); |
773 | |
774 | return FALSE; |
775 | } |
776 | |
777 | if (absolute < 0) |
778 | { |
779 | g_set_error_literal (err: error, |
780 | G_IO_ERROR, |
781 | code: G_IO_ERROR_INVALID_ARGUMENT, |
782 | _("Requested seek before the beginning of the stream" )); |
783 | return FALSE; |
784 | } |
785 | |
786 | /* Can't seek past the end of a fixed-size stream. |
787 | * |
788 | * Note: seeking to the non-existent byte at the end of a fixed-sized |
789 | * stream is valid (eg: a 1-byte fixed sized stream can have position |
790 | * 0 or 1). Therefore '>' is what we want. |
791 | * */ |
792 | if (priv->realloc_fn == NULL && (gsize) absolute > priv->len) |
793 | { |
794 | g_set_error_literal (err: error, |
795 | G_IO_ERROR, |
796 | code: G_IO_ERROR_INVALID_ARGUMENT, |
797 | _("Requested seek beyond the end of the stream" )); |
798 | return FALSE; |
799 | } |
800 | |
801 | priv->pos = absolute; |
802 | |
803 | return TRUE; |
804 | } |
805 | |
806 | static gboolean |
807 | g_memory_output_stream_can_truncate (GSeekable *seekable) |
808 | { |
809 | GMemoryOutputStream *ostream; |
810 | GMemoryOutputStreamPrivate *priv; |
811 | |
812 | ostream = G_MEMORY_OUTPUT_STREAM (seekable); |
813 | priv = ostream->priv; |
814 | |
815 | /* We do not allow truncation of fixed-sized streams */ |
816 | return priv->realloc_fn != NULL; |
817 | } |
818 | |
819 | static gboolean |
820 | g_memory_output_stream_truncate (GSeekable *seekable, |
821 | goffset offset, |
822 | GCancellable *cancellable, |
823 | GError **error) |
824 | { |
825 | GMemoryOutputStream *ostream = G_MEMORY_OUTPUT_STREAM (seekable); |
826 | |
827 | if (!array_resize (ostream, size: offset, FALSE, error)) |
828 | return FALSE; |
829 | |
830 | ostream->priv->valid_len = offset; |
831 | |
832 | return TRUE; |
833 | } |
834 | |
835 | static gboolean |
836 | g_memory_output_stream_is_writable (GPollableOutputStream *stream) |
837 | { |
838 | return TRUE; |
839 | } |
840 | |
841 | static GSource * |
842 | g_memory_output_stream_create_source (GPollableOutputStream *stream, |
843 | GCancellable *cancellable) |
844 | { |
845 | GSource *base_source, *pollable_source; |
846 | |
847 | base_source = g_timeout_source_new (interval: 0); |
848 | pollable_source = g_pollable_source_new_full (pollable_stream: stream, child_source: base_source, cancellable); |
849 | g_source_unref (source: base_source); |
850 | |
851 | return pollable_source; |
852 | } |
853 | |