target/arm: Prepare for CONTROL.SPSEL being nonzero in Handler mode
[qemu/kevin.git] / chardev / char-pty.c
blob761ae6dec16c5deac3753181ae38549a8fa47a49
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 "qapi/error.h"
26 #include "qemu-common.h"
27 #include "chardev/char.h"
28 #include "io/channel-file.h"
29 #include "qemu/sockets.h"
30 #include "qemu/error-report.h"
32 #include "chardev/char-io.h"
34 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
35 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \
36 || defined(__GLIBC__)
38 typedef struct {
39 Chardev parent;
40 QIOChannel *ioc;
41 int read_bytes;
43 /* Protected by the Chardev chr_write_lock. */
44 int connected;
45 guint timer_tag;
46 guint open_tag;
47 } PtyChardev;
49 #define PTY_CHARDEV(obj) OBJECT_CHECK(PtyChardev, (obj), TYPE_CHARDEV_PTY)
51 static void pty_chr_update_read_handler_locked(Chardev *chr);
52 static void pty_chr_state(Chardev *chr, int connected);
54 static gboolean pty_chr_timer(gpointer opaque)
56 struct Chardev *chr = CHARDEV(opaque);
57 PtyChardev *s = PTY_CHARDEV(opaque);
59 qemu_mutex_lock(&chr->chr_write_lock);
60 s->timer_tag = 0;
61 s->open_tag = 0;
62 if (!s->connected) {
63 /* Next poll ... */
64 pty_chr_update_read_handler_locked(chr);
66 qemu_mutex_unlock(&chr->chr_write_lock);
67 return FALSE;
70 /* Called with chr_write_lock held. */
71 static void pty_chr_rearm_timer(Chardev *chr, int ms)
73 PtyChardev *s = PTY_CHARDEV(chr);
74 char *name;
76 if (s->timer_tag) {
77 g_source_remove(s->timer_tag);
78 s->timer_tag = 0;
81 if (ms == 1000) {
82 name = g_strdup_printf("pty-timer-secs-%s", chr->label);
83 s->timer_tag = g_timeout_add_seconds(1, pty_chr_timer, chr);
84 } else {
85 name = g_strdup_printf("pty-timer-ms-%s", chr->label);
86 s->timer_tag = g_timeout_add(ms, pty_chr_timer, chr);
88 g_source_set_name_by_id(s->timer_tag, name);
89 g_free(name);
92 /* Called with chr_write_lock held. */
93 static void pty_chr_update_read_handler_locked(Chardev *chr)
95 PtyChardev *s = PTY_CHARDEV(chr);
96 GPollFD pfd;
97 int rc;
98 QIOChannelFile *fioc = QIO_CHANNEL_FILE(s->ioc);
100 pfd.fd = fioc->fd;
101 pfd.events = G_IO_OUT;
102 pfd.revents = 0;
103 do {
104 rc = g_poll(&pfd, 1, 0);
105 } while (rc == -1 && errno == EINTR);
106 assert(rc >= 0);
108 if (pfd.revents & G_IO_HUP) {
109 pty_chr_state(chr, 0);
110 } else {
111 pty_chr_state(chr, 1);
115 static void pty_chr_update_read_handler(Chardev *chr)
117 qemu_mutex_lock(&chr->chr_write_lock);
118 pty_chr_update_read_handler_locked(chr);
119 qemu_mutex_unlock(&chr->chr_write_lock);
122 /* Called with chr_write_lock held. */
123 static int char_pty_chr_write(Chardev *chr, const uint8_t *buf, int len)
125 PtyChardev *s = PTY_CHARDEV(chr);
127 if (!s->connected) {
128 /* guest sends data, check for (re-)connect */
129 pty_chr_update_read_handler_locked(chr);
130 if (!s->connected) {
131 return len;
134 return io_channel_send(s->ioc, buf, len);
137 static GSource *pty_chr_add_watch(Chardev *chr, GIOCondition cond)
139 PtyChardev *s = PTY_CHARDEV(chr);
140 if (!s->connected) {
141 return NULL;
143 return qio_channel_create_watch(s->ioc, cond);
146 static int pty_chr_read_poll(void *opaque)
148 Chardev *chr = CHARDEV(opaque);
149 PtyChardev *s = PTY_CHARDEV(opaque);
151 s->read_bytes = qemu_chr_be_can_write(chr);
152 return s->read_bytes;
155 static gboolean pty_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque)
157 Chardev *chr = CHARDEV(opaque);
158 PtyChardev *s = PTY_CHARDEV(opaque);
159 gsize len;
160 uint8_t buf[CHR_READ_BUF_LEN];
161 ssize_t ret;
163 len = sizeof(buf);
164 if (len > s->read_bytes) {
165 len = s->read_bytes;
167 if (len == 0) {
168 return TRUE;
170 ret = qio_channel_read(s->ioc, (char *)buf, len, NULL);
171 if (ret <= 0) {
172 pty_chr_state(chr, 0);
173 return FALSE;
174 } else {
175 pty_chr_state(chr, 1);
176 qemu_chr_be_write(chr, buf, ret);
178 return TRUE;
181 static gboolean qemu_chr_be_generic_open_func(gpointer opaque)
183 Chardev *chr = CHARDEV(opaque);
184 PtyChardev *s = PTY_CHARDEV(opaque);
186 s->open_tag = 0;
187 qemu_chr_be_event(chr, CHR_EVENT_OPENED);
188 return FALSE;
191 /* Called with chr_write_lock held. */
192 static void pty_chr_state(Chardev *chr, int connected)
194 PtyChardev *s = PTY_CHARDEV(chr);
196 if (!connected) {
197 if (s->open_tag) {
198 g_source_remove(s->open_tag);
199 s->open_tag = 0;
201 remove_fd_in_watch(chr);
202 s->connected = 0;
203 /* (re-)connect poll interval for idle guests: once per second.
204 * We check more frequently in case the guests sends data to
205 * the virtual device linked to our pty. */
206 pty_chr_rearm_timer(chr, 1000);
207 } else {
208 if (s->timer_tag) {
209 g_source_remove(s->timer_tag);
210 s->timer_tag = 0;
212 if (!s->connected) {
213 g_assert(s->open_tag == 0);
214 s->connected = 1;
215 s->open_tag = g_idle_add(qemu_chr_be_generic_open_func, chr);
217 if (!chr->gsource) {
218 chr->gsource = io_add_watch_poll(chr, s->ioc,
219 pty_chr_read_poll,
220 pty_chr_read,
221 chr, chr->gcontext);
226 static void char_pty_finalize(Object *obj)
228 Chardev *chr = CHARDEV(obj);
229 PtyChardev *s = PTY_CHARDEV(obj);
231 qemu_mutex_lock(&chr->chr_write_lock);
232 pty_chr_state(chr, 0);
233 object_unref(OBJECT(s->ioc));
234 if (s->timer_tag) {
235 g_source_remove(s->timer_tag);
236 s->timer_tag = 0;
238 qemu_mutex_unlock(&chr->chr_write_lock);
239 qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
242 static void char_pty_open(Chardev *chr,
243 ChardevBackend *backend,
244 bool *be_opened,
245 Error **errp)
247 PtyChardev *s;
248 int master_fd, slave_fd;
249 char pty_name[PATH_MAX];
250 char *name;
252 master_fd = qemu_openpty_raw(&slave_fd, pty_name);
253 if (master_fd < 0) {
254 error_setg_errno(errp, errno, "Failed to create PTY");
255 return;
258 close(slave_fd);
259 qemu_set_nonblock(master_fd);
261 chr->filename = g_strdup_printf("pty:%s", pty_name);
262 error_report("char device redirected to %s (label %s)",
263 pty_name, chr->label);
265 s = PTY_CHARDEV(chr);
266 s->ioc = QIO_CHANNEL(qio_channel_file_new_fd(master_fd));
267 name = g_strdup_printf("chardev-pty-%s", chr->label);
268 qio_channel_set_name(QIO_CHANNEL(s->ioc), name);
269 g_free(name);
270 s->timer_tag = 0;
271 *be_opened = false;
274 static void char_pty_class_init(ObjectClass *oc, void *data)
276 ChardevClass *cc = CHARDEV_CLASS(oc);
278 cc->open = char_pty_open;
279 cc->chr_write = char_pty_chr_write;
280 cc->chr_update_read_handler = pty_chr_update_read_handler;
281 cc->chr_add_watch = pty_chr_add_watch;
284 static const TypeInfo char_pty_type_info = {
285 .name = TYPE_CHARDEV_PTY,
286 .parent = TYPE_CHARDEV,
287 .instance_size = sizeof(PtyChardev),
288 .instance_finalize = char_pty_finalize,
289 .class_init = char_pty_class_init,
292 static void register_types(void)
294 type_register_static(&char_pty_type_info);
297 type_init(register_types);
299 #endif