[qemu.git] / chardev / char-pty.c

/*
 * 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 "qapi/error.h"
#include "qemu-common.h"
#include "chardev/char.h"
#include "io/channel-file.h"
#include "qemu/sockets.h"
#include "qemu/error-report.h"

#include "chardev/char-io.h"

#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__)      \
    || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \
    || defined(__GLIBC__)

typedef struct {
    Chardev parent;
    QIOChannel *ioc;
    int read_bytes;

    /* Protected by the Chardev chr_write_lock.  */
    int connected;
    guint timer_tag;
    guint open_tag;
} PtyChardev;

#define PTY_CHARDEV(obj) OBJECT_CHECK(PtyChardev, (obj), TYPE_CHARDEV_PTY)

static void pty_chr_update_read_handler_locked(Chardev *chr);
static void pty_chr_state(Chardev *chr, int connected);

static gboolean pty_chr_timer(gpointer opaque)
{
    struct Chardev *chr = CHARDEV(opaque);
    PtyChardev *s = PTY_CHARDEV(opaque);

    qemu_mutex_lock(&chr->chr_write_lock);
    s->timer_tag = 0;
    s->open_tag = 0;
    if (!s->connected) {
        /* Next poll ... */
        pty_chr_update_read_handler_locked(chr);
    }
    qemu_mutex_unlock(&chr->chr_write_lock);
    return FALSE;
}

/* Called with chr_write_lock held.  */
static void pty_chr_rearm_timer(Chardev *chr, int ms)
{
    PtyChardev *s = PTY_CHARDEV(chr);
    char *name;

    if (s->timer_tag) {
        g_source_remove(s->timer_tag);
        s->timer_tag = 0;
    }

    if (ms == 1000) {
        name = g_strdup_printf("pty-timer-secs-%s", chr->label);
        s->timer_tag = g_timeout_add_seconds(1, pty_chr_timer, chr);
    } else {
        name = g_strdup_printf("pty-timer-ms-%s", chr->label);
        s->timer_tag = g_timeout_add(ms, pty_chr_timer, chr);
    }
    g_source_set_name_by_id(s->timer_tag, name);
    g_free(name);
}

/* Called with chr_write_lock held.  */
static void pty_chr_update_read_handler_locked(Chardev *chr)
{
    PtyChardev *s = PTY_CHARDEV(chr);
    GPollFD pfd;
    int rc;
    QIOChannelFile *fioc = QIO_CHANNEL_FILE(s->ioc);

    pfd.fd = fioc->fd;
    pfd.events = G_IO_OUT;
    pfd.revents = 0;
    do {
        rc = g_poll(&pfd, 1, 0);
    } while (rc == -1 && errno == EINTR);
    assert(rc >= 0);

    if (pfd.revents & G_IO_HUP) {
        pty_chr_state(chr, 0);
    } else {
        pty_chr_state(chr, 1);
    }
}

static void pty_chr_update_read_handler(Chardev *chr,
                                        GMainContext *context)
{
    qemu_mutex_lock(&chr->chr_write_lock);
    pty_chr_update_read_handler_locked(chr);
    qemu_mutex_unlock(&chr->chr_write_lock);
}

/* Called with chr_write_lock held.  */
static int char_pty_chr_write(Chardev *chr, const uint8_t *buf, int len)
{
    PtyChardev *s = PTY_CHARDEV(chr);

    if (!s->connected) {
        /* guest sends data, check for (re-)connect */
        pty_chr_update_read_handler_locked(chr);
        if (!s->connected) {
            return len;
        }
    }
    return io_channel_send(s->ioc, buf, len);
}

static GSource *pty_chr_add_watch(Chardev *chr, GIOCondition cond)
{
    PtyChardev *s = PTY_CHARDEV(chr);
    if (!s->connected) {
        return NULL;
    }
    return qio_channel_create_watch(s->ioc, cond);
}

static int pty_chr_read_poll(void *opaque)
{
    Chardev *chr = CHARDEV(opaque);
    PtyChardev *s = PTY_CHARDEV(opaque);

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

static gboolean pty_chr_read(QIOChannel *chan, GIOCondition cond, void *opaque)
{
    Chardev *chr = CHARDEV(opaque);
    PtyChardev *s = PTY_CHARDEV(opaque);
    gsize len;
    uint8_t buf[CHR_READ_BUF_LEN];
    ssize_t ret;

    len = sizeof(buf);
    if (len > s->read_bytes) {
        len = s->read_bytes;
    }
    if (len == 0) {
        return TRUE;
    }
    ret = qio_channel_read(s->ioc, (char *)buf, len, NULL);
    if (ret <= 0) {
        pty_chr_state(chr, 0);
        return FALSE;
    } else {
        pty_chr_state(chr, 1);
        qemu_chr_be_write(chr, buf, ret);
    }
    return TRUE;
}

static gboolean qemu_chr_be_generic_open_func(gpointer opaque)
{
    Chardev *chr = CHARDEV(opaque);
    PtyChardev *s = PTY_CHARDEV(opaque);

    s->open_tag = 0;
    qemu_chr_be_event(chr, CHR_EVENT_OPENED);
    return FALSE;
}

/* Called with chr_write_lock held.  */
static void pty_chr_state(Chardev *chr, int connected)
{
    PtyChardev *s = PTY_CHARDEV(chr);

    if (!connected) {
        if (s->open_tag) {
            g_source_remove(s->open_tag);
            s->open_tag = 0;
        }
        remove_fd_in_watch(chr);
        s->connected = 0;
        /* (re-)connect poll interval for idle guests: once per second.
         * We check more frequently in case the guests sends data to
         * the virtual device linked to our pty. */
        pty_chr_rearm_timer(chr, 1000);
    } else {
        if (s->timer_tag) {
            g_source_remove(s->timer_tag);
            s->timer_tag = 0;
        }
        if (!s->connected) {
            g_assert(s->open_tag == 0);
            s->connected = 1;
            s->open_tag = g_idle_add(qemu_chr_be_generic_open_func, chr);
        }
        if (!chr->gsource) {
            chr->gsource = io_add_watch_poll(chr, s->ioc,
                                               pty_chr_read_poll,
                                               pty_chr_read,
                                               chr, NULL);
        }
    }
}

static void char_pty_finalize(Object *obj)
{
    Chardev *chr = CHARDEV(obj);
    PtyChardev *s = PTY_CHARDEV(obj);

    qemu_mutex_lock(&chr->chr_write_lock);
    pty_chr_state(chr, 0);
    object_unref(OBJECT(s->ioc));
    if (s->timer_tag) {
        g_source_remove(s->timer_tag);
        s->timer_tag = 0;
    }
    qemu_mutex_unlock(&chr->chr_write_lock);
    qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
}

static void char_pty_open(Chardev *chr,
                          ChardevBackend *backend,
                          bool *be_opened,
                          Error **errp)
{
    PtyChardev *s;
    int master_fd, slave_fd;
    char pty_name[PATH_MAX];
    char *name;

    master_fd = qemu_openpty_raw(&slave_fd, pty_name);
    if (master_fd < 0) {
        error_setg_errno(errp, errno, "Failed to create PTY");
        return;
    }

    close(slave_fd);
    qemu_set_nonblock(master_fd);

    chr->filename = g_strdup_printf("pty:%s", pty_name);
    error_report("char device redirected to %s (label %s)",
                 pty_name, chr->label);

    s = PTY_CHARDEV(chr);
    s->ioc = QIO_CHANNEL(qio_channel_file_new_fd(master_fd));
    name = g_strdup_printf("chardev-pty-%s", chr->label);
    qio_channel_set_name(QIO_CHANNEL(s->ioc), name);
    g_free(name);
    s->timer_tag = 0;
    *be_opened = false;
}

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

    cc->open = char_pty_open;
    cc->chr_write = char_pty_chr_write;
    cc->chr_update_read_handler = pty_chr_update_read_handler;
    cc->chr_add_watch = pty_chr_add_watch;
}

static const TypeInfo char_pty_type_info = {
    .name = TYPE_CHARDEV_PTY,
    .parent = TYPE_CHARDEV,
    .instance_size = sizeof(PtyChardev),
    .instance_finalize = char_pty_finalize,
    .class_init = char_pty_class_init,
};

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

type_init(register_types);

#endif
Commit	Line	Data
c3b7d620 MAL	1	/*
	2	* QEMU System Emulator
	3	*
	4	* Copyright (c) 2003-2008 Fabrice Bellard
	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 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:
	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
	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.
	23	*/
	24	#include "qemu/osdep.h"
	25	#include "qapi/error.h"
	26	#include "qemu-common.h"
8228e353	27	#include "chardev/char.h"
c3b7d620 MAL	28	#include "io/channel-file.h"
	29	#include "qemu/sockets.h"
	30	#include "qemu/error-report.h"
	31
8228e353	32	#include "chardev/char-io.h"
c3b7d620 MAL	33
	34	#if defined(__linux__) \|\| defined(__sun__) \|\| defined(__FreeBSD__) \
	35	\|\| defined(__NetBSD__) \|\| defined(__OpenBSD__) \|\| defined(__DragonFly__) \
	36	\|\| defined(__GLIBC__)
	37
	38	typedef struct {
	39	Chardev parent;
	40	QIOChannel *ioc;
	41	int read_bytes;
	42
	43	/* Protected by the Chardev chr_write_lock. */
	44	int connected;
	45	guint timer_tag;
	46	guint open_tag;
	47	} PtyChardev;
	48
	49	#define PTY_CHARDEV(obj) OBJECT_CHECK(PtyChardev, (obj), TYPE_CHARDEV_PTY)
	50
	51	static void pty_chr_update_read_handler_locked(Chardev *chr);
	52	static void pty_chr_state(Chardev *chr, int connected);
	53
	54	static gboolean pty_chr_timer(gpointer opaque)
	55	{
	56	struct Chardev *chr = CHARDEV(opaque);
	57	PtyChardev *s = PTY_CHARDEV(opaque);
	58
	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);
	65	}
	66	qemu_mutex_unlock(&chr->chr_write_lock);
	67	return FALSE;
	68	}
	69
	70	/* Called with chr_write_lock held. */
	71	static void pty_chr_rearm_timer(Chardev *chr, int ms)
	72	{
	73	PtyChardev *s = PTY_CHARDEV(chr);
	74	char *name;
	75
	76	if (s->timer_tag) {
	77	g_source_remove(s->timer_tag);
	78	s->timer_tag = 0;
	79	}
	80
	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);
	87	}
	88	g_source_set_name_by_id(s->timer_tag, name);
	89	g_free(name);
	90	}
	91
	92	/* Called with chr_write_lock held. */
	93	static void pty_chr_update_read_handler_locked(Chardev *chr)
	94	{
	95	PtyChardev *s = PTY_CHARDEV(chr);
	96	GPollFD pfd;
97	int rc;
98	QIOChannelFile *fioc = QIO_CHANNEL_FILE(s->ioc);
99
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);
107
108	if (pfd.revents & G_IO_HUP) {
109	pty_chr_state(chr, 0);
110	} else {
111	pty_chr_state(chr, 1);
112	}
113	}
114
115	static void pty_chr_update_read_handler(Chardev *chr,
116	GMainContext *context)
117	{
118	qemu_mutex_lock(&chr->chr_write_lock);
119	pty_chr_update_read_handler_locked(chr);
120	qemu_mutex_unlock(&chr->chr_write_lock);
121	}
122
123	/* Called with chr_write_lock held. */
124	static int char_pty_chr_write(Chardev chr, const uint8_t buf, int len)
125	{
126	PtyChardev *s = PTY_CHARDEV(chr);
127
128	if (!s->connected) {
129	/* guest sends data, check for (re-)connect */
130	pty_chr_update_read_handler_locked(chr);
131	if (!s->connected) {
1c64fdbc	132	return len;
c3b7d620 MAL	133	}
	134	}
	135	return io_channel_send(s->ioc, buf, len);
	136	}
	137
	138	static GSource pty_chr_add_watch(Chardev chr, GIOCondition cond)
	139	{
	140	PtyChardev *s = PTY_CHARDEV(chr);
	141	if (!s->connected) {
	142	return NULL;
	143	}
	144	return qio_channel_create_watch(s->ioc, cond);
	145	}
	146
	147	static int pty_chr_read_poll(void *opaque)
	148	{
	149	Chardev *chr = CHARDEV(opaque);
	150	PtyChardev *s = PTY_CHARDEV(opaque);
	151
	152	s->read_bytes = qemu_chr_be_can_write(chr);
	153	return s->read_bytes;
	154	}
	155
	156	static gboolean pty_chr_read(QIOChannel chan, GIOCondition cond, void opaque)
	157	{
	158	Chardev *chr = CHARDEV(opaque);
	159	PtyChardev *s = PTY_CHARDEV(opaque);
	160	gsize len;
	161	uint8_t buf[CHR_READ_BUF_LEN];
	162	ssize_t ret;
	163
	164	len = sizeof(buf);
	165	if (len > s->read_bytes) {
	166	len = s->read_bytes;
	167	}
	168	if (len == 0) {
	169	return TRUE;
	170	}
	171	ret = qio_channel_read(s->ioc, (char *)buf, len, NULL);
	172	if (ret <= 0) {
	173	pty_chr_state(chr, 0);
	174	return FALSE;
	175	} else {
	176	pty_chr_state(chr, 1);
	177	qemu_chr_be_write(chr, buf, ret);
	178	}
	179	return TRUE;
	180	}
	181
	182	static gboolean qemu_chr_be_generic_open_func(gpointer opaque)
	183	{
	184	Chardev *chr = CHARDEV(opaque);
	185	PtyChardev *s = PTY_CHARDEV(opaque);
	186
	187	s->open_tag = 0;
63618135	188	qemu_chr_be_event(chr, CHR_EVENT_OPENED);
c3b7d620 MAL	189	return FALSE;
	190	}
	191
	192	/* Called with chr_write_lock held. */
	193	static void pty_chr_state(Chardev *chr, int connected)
	194	{
	195	PtyChardev *s = PTY_CHARDEV(chr);
	196
	197	if (!connected) {
	198	if (s->open_tag) {
	199	g_source_remove(s->open_tag);
	200	s->open_tag = 0;
	201	}
b19456dd	202	remove_fd_in_watch(chr);
c3b7d620 MAL	203	s->connected = 0;
	204	/* (re-)connect poll interval for idle guests: once per second.
	205	* We check more frequently in case the guests sends data to
	206	* the virtual device linked to our pty. */
	207	pty_chr_rearm_timer(chr, 1000);
	208	} else {
	209	if (s->timer_tag) {
	210	g_source_remove(s->timer_tag);
	211	s->timer_tag = 0;
	212	}
	213	if (!s->connected) {
	214	g_assert(s->open_tag == 0);
	215	s->connected = 1;
	216	s->open_tag = g_idle_add(qemu_chr_be_generic_open_func, chr);
	217	}
b19456dd HZ	218	if (!chr->gsource) {
b19456dd HZ	219	chr->gsource = io_add_watch_poll(chr, s->ioc,
c3b7d620 MAL	220	pty_chr_read_poll,
	221	pty_chr_read,
	222	chr, NULL);
	223	}
	224	}
	225	}
	226
	227	static void char_pty_finalize(Object *obj)
	228	{
	229	Chardev *chr = CHARDEV(obj);
	230	PtyChardev *s = PTY_CHARDEV(obj);
	231
	232	qemu_mutex_lock(&chr->chr_write_lock);
	233	pty_chr_state(chr, 0);
	234	object_unref(OBJECT(s->ioc));
	235	if (s->timer_tag) {
	236	g_source_remove(s->timer_tag);
	237	s->timer_tag = 0;
	238	}
	239	qemu_mutex_unlock(&chr->chr_write_lock);
	240	qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
	241	}
	242
	243	static void char_pty_open(Chardev *chr,
	244	ChardevBackend *backend,
	245	bool *be_opened,
	246	Error **errp)
	247	{
	248	PtyChardev *s;
	249	int master_fd, slave_fd;
	250	char pty_name[PATH_MAX];
	251	char *name;
	252
	253	master_fd = qemu_openpty_raw(&slave_fd, pty_name);
	254	if (master_fd < 0) {
	255	error_setg_errno(errp, errno, "Failed to create PTY");
	256	return;
	257	}
	258
	259	close(slave_fd);
	260	qemu_set_nonblock(master_fd);
	261
	262	chr->filename = g_strdup_printf("pty:%s", pty_name);
	263	error_report("char device redirected to %s (label %s)",
	264	pty_name, chr->label);
	265
	266	s = PTY_CHARDEV(chr);
	267	s->ioc = QIO_CHANNEL(qio_channel_file_new_fd(master_fd));
	268	name = g_strdup_printf("chardev-pty-%s", chr->label);
	269	qio_channel_set_name(QIO_CHANNEL(s->ioc), name);
	270	g_free(name);
	271	s->timer_tag = 0;
	272	*be_opened = false;
	273	}
	274
	275	static void char_pty_class_init(ObjectClass oc, void data)
	276	{
	277	ChardevClass *cc = CHARDEV_CLASS(oc);
	278
	279	cc->open = char_pty_open;
	280	cc->chr_write = char_pty_chr_write;
	281	cc->chr_update_read_handler = pty_chr_update_read_handler;
	282	cc->chr_add_watch = pty_chr_add_watch;
	283	}
284
285	static const TypeInfo char_pty_type_info = {
286	.name = TYPE_CHARDEV_PTY,
287	.parent = TYPE_CHARDEV,
288	.instance_size = sizeof(PtyChardev),
289	.instance_finalize = char_pty_finalize,
290	.class_init = char_pty_class_init,
291	};
292
293	static void register_types(void)
294	{
295	type_register_static(&char_pty_type_info);
296	}
297
298	type_init(register_types);
299
300	#endif