slirp: fix domainname version availability
[qemu/ar7.git] / chardev / char-io.c
blobf81052481a557f660ab162a7dd59e52cb0eead33
1 /*
2 * QEMU System Emulator
4 * Copyright (c) 2003-2008 Fabrice Bellard
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 deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
24 #include "qemu/osdep.h"
25 #include "chardev/char-io.h"
27 typedef struct IOWatchPoll {
28 GSource parent;
30 QIOChannel *ioc;
31 GSource *src;
33 IOCanReadHandler *fd_can_read;
34 GSourceFunc fd_read;
35 void *opaque;
36 GMainContext *context;
37 } IOWatchPoll;
39 static IOWatchPoll *io_watch_poll_from_source(GSource *source)
41 return container_of(source, IOWatchPoll, parent);
44 static gboolean io_watch_poll_prepare(GSource *source,
45 gint *timeout)
47 IOWatchPoll *iwp = io_watch_poll_from_source(source);
48 bool now_active = iwp->fd_can_read(iwp->opaque) > 0;
49 bool was_active = iwp->src != NULL;
50 if (was_active == now_active) {
51 return FALSE;
54 if (now_active) {
55 iwp->src = qio_channel_create_watch(
56 iwp->ioc, G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL);
57 g_source_set_callback(iwp->src, iwp->fd_read, iwp->opaque, NULL);
58 g_source_attach(iwp->src, iwp->context);
59 } else {
60 g_source_destroy(iwp->src);
61 g_source_unref(iwp->src);
62 iwp->src = NULL;
64 return FALSE;
67 static gboolean io_watch_poll_check(GSource *source)
69 return FALSE;
72 static gboolean io_watch_poll_dispatch(GSource *source, GSourceFunc callback,
73 gpointer user_data)
75 abort();
78 static void io_watch_poll_finalize(GSource *source)
80 /* Due to a glib bug, removing the last reference to a source
81 * inside a finalize callback causes recursive locking (and a
82 * deadlock). This is not a problem inside other callbacks,
83 * including dispatch callbacks, so we call io_remove_watch_poll
84 * to remove this source. At this point, iwp->src must
85 * be NULL, or we would leak it.
87 * This would be solved much more elegantly by child sources,
88 * but we support older glib versions that do not have them.
90 IOWatchPoll *iwp = io_watch_poll_from_source(source);
91 assert(iwp->src == NULL);
94 static GSourceFuncs io_watch_poll_funcs = {
95 .prepare = io_watch_poll_prepare,
96 .check = io_watch_poll_check,
97 .dispatch = io_watch_poll_dispatch,
98 .finalize = io_watch_poll_finalize,
101 GSource *io_add_watch_poll(Chardev *chr,
102 QIOChannel *ioc,
103 IOCanReadHandler *fd_can_read,
104 QIOChannelFunc fd_read,
105 gpointer user_data,
106 GMainContext *context)
108 IOWatchPoll *iwp;
109 char *name;
111 iwp = (IOWatchPoll *) g_source_new(&io_watch_poll_funcs,
112 sizeof(IOWatchPoll));
113 iwp->fd_can_read = fd_can_read;
114 iwp->opaque = user_data;
115 iwp->ioc = ioc;
116 iwp->fd_read = (GSourceFunc) fd_read;
117 iwp->src = NULL;
118 iwp->context = context;
120 name = g_strdup_printf("chardev-iowatch-%s", chr->label);
121 g_source_set_name((GSource *)iwp, name);
122 g_free(name);
124 g_source_attach(&iwp->parent, context);
125 g_source_unref(&iwp->parent);
126 return (GSource *)iwp;
129 static void io_remove_watch_poll(GSource *source)
131 IOWatchPoll *iwp;
133 iwp = io_watch_poll_from_source(source);
134 if (iwp->src) {
135 g_source_destroy(iwp->src);
136 g_source_unref(iwp->src);
137 iwp->src = NULL;
139 g_source_destroy(&iwp->parent);
142 void remove_fd_in_watch(Chardev *chr)
144 if (chr->gsource) {
145 io_remove_watch_poll(chr->gsource);
146 chr->gsource = NULL;
150 int io_channel_send_full(QIOChannel *ioc,
151 const void *buf, size_t len,
152 int *fds, size_t nfds)
154 size_t offset = 0;
156 while (offset < len) {
157 ssize_t ret = 0;
158 struct iovec iov = { .iov_base = (char *)buf + offset,
159 .iov_len = len - offset };
161 ret = qio_channel_writev_full(
162 ioc, &iov, 1,
163 fds, nfds, NULL);
164 if (ret == QIO_CHANNEL_ERR_BLOCK) {
165 if (offset) {
166 return offset;
169 errno = EAGAIN;
170 return -1;
171 } else if (ret < 0) {
172 errno = EINVAL;
173 return -1;
176 offset += ret;
179 return offset;
182 int io_channel_send(QIOChannel *ioc, const void *buf, size_t len)
184 return io_channel_send_full(ioc, buf, len, NULL, 0);