xref: /aosp_15_r20/external/libwebsockets/lib/misc/lwsac/lwsac.cxx (revision 1c60b9aca93fdbc9b5f19b2d2194c91294b22281)
1 /*
2  * libwebsockets - small server side websockets and web server implementation
3  *
4  * Copyright (C) 2020 Andy Green <[email protected]>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22  * IN THE SOFTWARE.
23  *
24  * C++ classes for Secure Streams - atomic heap messages
25  */
26 
27 #include <libwebsockets.hxx>
28 #include "private-lib-misc-lwsac.h"
29 
30 void
start(bool atomic)31 lssAc::start(bool atomic)
32 {
33 	if (atomic && ac->next) {
34 		struct lwsac *ac2 = NULL, *i;
35 		size_t total = (size_t)lwsac_total_alloc(ac);
36 		uint8_t *p = (uint8_t *)lwsac_use(&ac2, total, total);
37 
38 		/*
39 		 * He wants a single linear buffer, and we have more than one
40 		 * piece... let's make a new, single one, copy the fragments
41 		 * in and replace the fragmented one with the unified copy.
42 		 */
43 
44 		i = ac;
45 		while (i) {
46 			size_t bl = lwsac_get_tail_pos(i) -
47 						lwsac_sizeof(i == ac);
48 			memcpy(p, (uint8_t *)i + lwsac_sizeof(i == ac), bl);
49 			p += bl;
50 		}
51 
52 		lwsac_free(&ac);
53 		ac = ac2;
54 	}
55 
56 	iter = ac;
57 }
58 
59 int
get(lssbuf_t * lb)60 lssAc::get(lssbuf_t *lb)
61 {
62 	if (!ac)
63 		return 1;
64 
65 	lb->buf = (uint8_t *)iter + lwsac_sizeof(iter == ac);
66 	lb->len = lwsac_get_tail_pos(iter) - lwsac_sizeof(iter == ac);
67 	iter = iter->next;
68 
69 	return 0;
70 }
71 
72 void
append(lssbuf_t * lb)73 lssAc::append(lssbuf_t *lb)
74 {
75 	uint8_t *p = (uint8_t *)lwsac_use(&ac, lb->len, lb->len);
76 
77 	if (!p)
78 		throw lssException("oom");
79 	memcpy(p, lb->buf, lb->len);
80 }
81