qemu/chardev/char-pty.c
Marc-André Lureau 3f6c2e8b79 char: move qemu_openpty_raw from util/ to char/
It is only needed by char-pty.

Fix the code style while at it.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-6-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 10:50:37 +02:00

367 lines
9.1 KiB
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 "qemu-common.h"
#include "qapi/error.h"
#include "chardev/char.h"
#include "io/channel-file.h"
#include "qemu/sockets.h"
#include "qemu/error-report.h"
#include "qemu/module.h"
#include "qemu/qemu-print.h"
#include "chardev/char-io.h"
#include "qom/object.h"
struct PtyChardev {
Chardev parent;
QIOChannel *ioc;
int read_bytes;
int connected;
GSource *timer_src;
};
typedef struct PtyChardev PtyChardev;
DECLARE_INSTANCE_CHECKER(PtyChardev, PTY_CHARDEV,
TYPE_CHARDEV_PTY)
static void pty_chr_state(Chardev *chr, int connected);
static void pty_chr_timer_cancel(PtyChardev *s)
{
if (s->timer_src) {
g_source_destroy(s->timer_src);
g_source_unref(s->timer_src);
s->timer_src = NULL;
}
}
static gboolean pty_chr_timer(gpointer opaque)
{
struct Chardev *chr = CHARDEV(opaque);
PtyChardev *s = PTY_CHARDEV(opaque);
pty_chr_timer_cancel(s);
if (!s->connected) {
/* Next poll ... */
qemu_chr_be_update_read_handlers(chr, chr->gcontext);
}
return FALSE;
}
static void pty_chr_rearm_timer(Chardev *chr, int ms)
{
PtyChardev *s = PTY_CHARDEV(chr);
char *name;
pty_chr_timer_cancel(s);
name = g_strdup_printf("pty-timer-%s", chr->label);
s->timer_src = qemu_chr_timeout_add_ms(chr, ms, pty_chr_timer, chr);
g_source_set_name(s->timer_src, name);
g_free(name);
}
static void pty_chr_update_read_handler(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 int char_pty_chr_write(Chardev *chr, const uint8_t *buf, int len)
{
PtyChardev *s = PTY_CHARDEV(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 void pty_chr_state(Chardev *chr, int connected)
{
PtyChardev *s = PTY_CHARDEV(chr);
if (!connected) {
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 {
pty_chr_timer_cancel(s);
if (!s->connected) {
s->connected = 1;
qemu_chr_be_event(chr, CHR_EVENT_OPENED);
}
if (!chr->gsource) {
chr->gsource = io_add_watch_poll(chr, s->ioc,
pty_chr_read_poll,
pty_chr_read,
chr, chr->gcontext);
}
}
}
static void char_pty_finalize(Object *obj)
{
Chardev *chr = CHARDEV(obj);
PtyChardev *s = PTY_CHARDEV(obj);
pty_chr_state(chr, 0);
object_unref(OBJECT(s->ioc));
pty_chr_timer_cancel(s);
qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
}
#if defined HAVE_PTY_H
# include <pty.h>
#elif defined CONFIG_BSD
# include <termios.h>
# if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
# include <libutil.h>
# else
# include <util.h>
# endif
#elif defined CONFIG_SOLARIS
# include <termios.h>
# include <stropts.h>
#else
# include <termios.h>
#endif
#ifdef __sun__
#if !defined(HAVE_OPENPTY)
/* Once illumos has openpty(), this is going to be removed. */
static int openpty(int *amaster, int *aslave, char *name,
struct termios *termp, struct winsize *winp)
{
const char *slave;
int mfd = -1, sfd = -1;
*amaster = *aslave = -1;
mfd = open("/dev/ptmx", O_RDWR | O_NOCTTY);
if (mfd < 0) {
goto err;
}
if (grantpt(mfd) == -1 || unlockpt(mfd) == -1) {
goto err;
}
if ((slave = ptsname(mfd)) == NULL) {
goto err;
}
if ((sfd = open(slave, O_RDONLY | O_NOCTTY)) == -1) {
goto err;
}
if (ioctl(sfd, I_PUSH, "ptem") == -1 ||
(termp != NULL && tcgetattr(sfd, termp) < 0)) {
goto err;
}
*amaster = mfd;
*aslave = sfd;
if (winp) {
ioctl(sfd, TIOCSWINSZ, winp);
}
return 0;
err:
if (sfd != -1) {
close(sfd);
}
close(mfd);
return -1;
}
#endif
static void cfmakeraw (struct termios *termios_p)
{
termios_p->c_iflag &=
~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
termios_p->c_oflag &= ~OPOST;
termios_p->c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
termios_p->c_cflag &= ~(CSIZE | PARENB);
termios_p->c_cflag |= CS8;
termios_p->c_cc[VMIN] = 0;
termios_p->c_cc[VTIME] = 0;
}
#endif
/* like openpty() but also makes it raw; return master fd */
static int qemu_openpty_raw(int *aslave, char *pty_name)
{
int amaster;
struct termios tty;
#if defined(__OpenBSD__) || defined(__DragonFly__)
char pty_buf[PATH_MAX];
#define q_ptsname(x) pty_buf
#else
char *pty_buf = NULL;
#define q_ptsname(x) ptsname(x)
#endif
if (openpty(&amaster, aslave, pty_buf, NULL, NULL) < 0) {
return -1;
}
/* Set raw attributes on the pty. */
tcgetattr(*aslave, &tty);
cfmakeraw(&tty);
tcsetattr(*aslave, TCSAFLUSH, &tty);
if (pty_name) {
strcpy(pty_name, q_ptsname(amaster));
}
return amaster;
}
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);
qemu_printf("char device redirected to %s (label %s)\n",
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_src = NULL;
*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);