1 /*
2 * QEMU Char Device for testsuite control
3 *
4 * Copyright (c) 2014 Red Hat, Inc.
5 *
6 * Author: Paolo Bonzini <pbonzini@redhat.com>
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26
27 #include "qemu/osdep.h"
28 #include "qemu/module.h"
29 #include "chardev/char.h"
30 #include "qom/object.h"
31
32 #define BUF_SIZE 32
33
34 struct TestdevChardev {
35 Chardev parent;
36
37 uint8_t in_buf[32];
38 int in_buf_used;
39 };
40 typedef struct TestdevChardev TestdevChardev;
41
42 #define TYPE_CHARDEV_TESTDEV "chardev-testdev"
DECLARE_INSTANCE_CHECKER(TestdevChardev,TESTDEV_CHARDEV,TYPE_CHARDEV_TESTDEV)43 DECLARE_INSTANCE_CHECKER(TestdevChardev, TESTDEV_CHARDEV,
44 TYPE_CHARDEV_TESTDEV)
45
46 /* Try to interpret a whole incoming packet */
47 static int testdev_eat_packet(TestdevChardev *testdev)
48 {
49 const uint8_t *cur = testdev->in_buf;
50 int len = testdev->in_buf_used;
51 uint8_t c;
52 int arg;
53
54 #define EAT(c) do { \
55 if (!len--) { \
56 return 0; \
57 } \
58 c = *cur++; \
59 } while (0)
60
61 EAT(c);
62
63 while (isspace(c)) {
64 EAT(c);
65 }
66
67 arg = 0;
68 while (isdigit(c)) {
69 arg = arg * 10 + c - '0';
70 EAT(c);
71 }
72
73 while (isspace(c)) {
74 EAT(c);
75 }
76
77 switch (c) {
78 case 'q':
79 exit((arg << 1) | 1);
80 break;
81 default:
82 break;
83 }
84 return cur - testdev->in_buf;
85 }
86
87 /* The other end is writing some data. Store it and try to interpret */
testdev_chr_write(Chardev * chr,const uint8_t * buf,int len)88 static int testdev_chr_write(Chardev *chr, const uint8_t *buf, int len)
89 {
90 TestdevChardev *testdev = TESTDEV_CHARDEV(chr);
91 int tocopy, eaten, orig_len = len;
92
93 while (len) {
94 /* Complete our buffer as much as possible */
95 tocopy = MIN(len, BUF_SIZE - testdev->in_buf_used);
96
97 memcpy(testdev->in_buf + testdev->in_buf_used, buf, tocopy);
98 testdev->in_buf_used += tocopy;
99 buf += tocopy;
100 len -= tocopy;
101
102 /* Interpret it as much as possible */
103 while (testdev->in_buf_used > 0 &&
104 (eaten = testdev_eat_packet(testdev)) > 0) {
105 memmove(testdev->in_buf, testdev->in_buf + eaten,
106 testdev->in_buf_used - eaten);
107 testdev->in_buf_used -= eaten;
108 }
109 }
110 return orig_len;
111 }
112
char_testdev_class_init(ObjectClass * oc,void * data)113 static void char_testdev_class_init(ObjectClass *oc, void *data)
114 {
115 ChardevClass *cc = CHARDEV_CLASS(oc);
116
117 cc->chr_write = testdev_chr_write;
118 }
119
120 static const TypeInfo char_testdev_type_info = {
121 .name = TYPE_CHARDEV_TESTDEV,
122 .parent = TYPE_CHARDEV,
123 .instance_size = sizeof(TestdevChardev),
124 .class_init = char_testdev_class_init,
125 };
126
register_types(void)127 static void register_types(void)
128 {
129 type_register_static(&char_testdev_type_info);
130 }
131
132 type_init(register_types);
133