summaryrefslogtreecommitdiff
path: root/chardev/char-fd.c
blob: 2c9b2ce56768d9742f6d37f499819b01cb77d5f8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
/*
 * QEMU System Emulator
 *
 * Copyright (c) 2003-2008 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "qemu/osdep.h"
#include "qemu/sockets.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "chardev/char.h"
#include "io/channel-file.h"

#include "chardev/char-fd.h"
#include "chardev/char-io.h"

/* Called with chr_write_lock held.  */
static int fd_chr_write(Chardev *chr, const uint8_t *buf, int len)
{
    FDChardev *s = FD_CHARDEV(chr);

    return io_channel_send(s->ioc_out, buf, len);
}

static gboolean fd_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque)
{
    Chardev *chr = CHARDEV(opaque);
    FDChardev *s = FD_CHARDEV(opaque);
    int len;
    uint8_t buf[CHR_READ_BUF_LEN];
    ssize_t ret;

    len = sizeof(buf);
    if (len > s->max_size) {
        len = s->max_size;
    }
    if (len == 0) {
        return TRUE;
    }

    ret = qio_channel_read(
        chan, (gchar *)buf, len, NULL);
    if (ret == 0) {
        remove_fd_in_watch(chr);
        qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
        return FALSE;
    }
    if (ret > 0) {
        qemu_chr_be_write(chr, buf, ret);
    }

    return TRUE;
}

static int fd_chr_read_poll(void *opaque)
{
    Chardev *chr = CHARDEV(opaque);
    FDChardev *s = FD_CHARDEV(opaque);

    s->max_size = qemu_chr_be_can_write(chr);
    return s->max_size;
}

static GSource *fd_chr_add_watch(Chardev *chr, GIOCondition cond)
{
    FDChardev *s = FD_CHARDEV(chr);
    return qio_channel_create_watch(s->ioc_out, cond);
}

static void fd_chr_update_read_handler(Chardev *chr)
{
    FDChardev *s = FD_CHARDEV(chr);

    remove_fd_in_watch(chr);
    if (s->ioc_in) {
        chr->gsource = io_add_watch_poll(chr, s->ioc_in,
                                           fd_chr_read_poll,
                                           fd_chr_read, chr,
                                           chr->gcontext);
    }
}

static void char_fd_finalize(Object *obj)
{
    Chardev *chr = CHARDEV(obj);
    FDChardev *s = FD_CHARDEV(obj);

    remove_fd_in_watch(chr);
    if (s->ioc_in) {
        object_unref(OBJECT(s->ioc_in));
    }
    if (s->ioc_out) {
        object_unref(OBJECT(s->ioc_out));
    }

    qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
}

int qmp_chardev_open_file_source(char *src, int flags, Error **errp)
{
    int fd = -1;

    TFR(fd = qemu_open(src, flags, 0666));
    if (fd == -1) {
        error_setg_file_open(errp, errno, src);
    }
    return fd;
}

/* open a character device to a unix fd */
void qemu_chr_open_fd(Chardev *chr,
                      int fd_in, int fd_out)
{
    FDChardev *s = FD_CHARDEV(chr);
    char *name;

    s->ioc_in = QIO_CHANNEL(qio_channel_file_new_fd(fd_in));
    name = g_strdup_printf("chardev-file-in-%s", chr->label);
    qio_channel_set_name(QIO_CHANNEL(s->ioc_in), name);
    g_free(name);
    s->ioc_out = QIO_CHANNEL(qio_channel_file_new_fd(fd_out));
    name = g_strdup_printf("chardev-file-out-%s", chr->label);
    qio_channel_set_name(QIO_CHANNEL(s->ioc_out), name);
    g_free(name);
    qemu_set_nonblock(fd_out);
}

static void char_fd_class_init(ObjectClass *oc, void *data)
{
    ChardevClass *cc = CHARDEV_CLASS(oc);

    cc->chr_add_watch = fd_chr_add_watch;
    cc->chr_write = fd_chr_write;
    cc->chr_update_read_handler = fd_chr_update_read_handler;
}

static const TypeInfo char_fd_type_info = {
    .name = TYPE_CHARDEV_FD,
    .parent = TYPE_CHARDEV,
    .instance_size = sizeof(FDChardev),
    .instance_finalize = char_fd_finalize,
    .class_init = char_fd_class_init,
    .abstract = true,
};

static void register_types(void)
{
    type_register_static(&char_fd_type_info);
}

type_init(register_types);