/* $OpenBSD: control.c,v 1.8 2021/03/02 04:10:07 jsg Exp $ */

/*

* Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>

*

* Permission to use, copy, modify, and distribute this software for any

* purpose with or without fee is hereby granted, provided that the above

* copyright notice and this permission notice appear in all copies.

*

* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

*/

#include <sys/types.h>

#include <sys/queue.h>

#include <sys/stat.h>

#include <sys/socket.h>

#include <sys/uio.h>

#include <sys/un.h>

#include <netinet/in.h>

#include <net/if.h>

#include <errno.h>

#include <event.h>

#include <imsg.h>

#include <limits.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include "amused.h"

#include "log.h"

#include "control.h"

#include "playlist.h"

#define CONTROL_BACKLOG 5

struct {

struct event ev;

struct event evt;

int fd;

struct playlist play;

int tx;

} control_state = {.fd = -1, .tx = -1};

struct ctl_conn {

TAILQ_ENTRY(ctl_conn) entry;

int monitor; /* 1 if client is in monitor mode */

struct imsgev iev;

};

TAILQ_HEAD(ctl_conns, ctl_conn) ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns);

struct ctl_conn *control_connbyfd(int);

struct ctl_conn *control_connbypid(pid_t);

void control_close(int);

int

control_init(char *path)

{

struct sockaddr_un sun;

int fd;

mode_t old_umask;

if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,

0)) == -1) {

log_warn("%s: socket", __func__);

return (-1);

}

memset(&sun, 0, sizeof(sun));

sun.sun_family = AF_UNIX;

strlcpy(sun.sun_path, path, sizeof(sun.sun_path));

if (unlink(path) == -1)

if (errno != ENOENT) {

log_warn("%s: unlink %s", __func__, path);

close(fd);

return (-1);

}

old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);

if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {

log_warn("%s: bind: %s", __func__, path);

close(fd);

umask(old_umask);

return (-1);

}

umask(old_umask);

if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {

log_warn("%s: chmod", __func__);

close(fd);

(void)unlink(path);

return (-1);

}

return (fd);

}

int

control_listen(int fd)

{

if (control_state.fd != -1)

fatalx("%s: received unexpected controlsock", __func__);

control_state.fd = fd;

if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {

log_warn("%s: listen", __func__);

return (-1);

}

event_set(&control_state.ev, control_state.fd, EV_READ,

control_accept, NULL);

event_add(&control_state.ev, NULL);

evtimer_set(&control_state.evt, control_accept, NULL);

return (0);

}

void

control_accept(int listenfd, short event, void *bula)

{

int connfd;

socklen_t len;

struct sockaddr_un sun;

struct ctl_conn *c;

event_add(&control_state.ev, NULL);

if ((event & EV_TIMEOUT))

return;

len = sizeof(sun);

if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len,

SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) {

/*

* Pause accept if we are out of file descriptors, or

* libevent will haunt us here too.

*/

if (errno == ENFILE || errno == EMFILE) {

struct timeval evtpause = { 1, 0 };

event_del(&control_state.ev);

evtimer_add(&control_state.evt, &evtpause);

} else if (errno != EWOULDBLOCK && errno != EINTR &&

errno != ECONNABORTED)

log_warn("%s: accept4", __func__);

return;

}

if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {

log_warn("%s: calloc", __func__);

close(connfd);

return;

}

imsg_init(&c->iev.ibuf, connfd);

c->iev.handler = control_dispatch_imsg;

c->iev.events = EV_READ;

event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,

c->iev.handler, &c->iev);

event_add(&c->iev.ev, NULL);

TAILQ_INSERT_TAIL(&ctl_conns, c, entry);

}

struct ctl_conn *

control_connbyfd(int fd)

{

struct ctl_conn *c;

TAILQ_FOREACH(c, &ctl_conns, entry) {

if (c->iev.ibuf.fd == fd)

break;

}

return (c);

}

struct ctl_conn *

control_connbypid(pid_t pid)

{

struct ctl_conn *c;

TAILQ_FOREACH(c, &ctl_conns, entry) {

if (c->iev.ibuf.pid == pid)

break;

}

return (c);

}

void

control_close(int fd)

{

struct ctl_conn *c;

if ((c = control_connbyfd(fd)) == NULL) {

log_warnx("%s: fd %d: not found", __func__, fd);

return;

}

/* abort the transaction if running by this user */

if (control_state.tx != -1 && c->iev.ibuf.fd == control_state.tx) {

playlist_free(&control_state.play);

control_state.tx = -1;

}

msgbuf_clear(&c->iev.ibuf.w);

TAILQ_REMOVE(&ctl_conns, c, entry);

event_del(&c->iev.ev);

close(c->iev.ibuf.fd);

/* Some file descriptors are available again. */

if (evtimer_pending(&control_state.evt, NULL)) {

evtimer_del(&control_state.evt);

event_add(&control_state.ev, NULL);

}

free(c);

}

void

control_notify(struct imsgev *iev, int type)

{

struct ctl_conn *c;

TAILQ_FOREACH(c, &ctl_conns, entry) {

if (&c->iev == iev || !c->monitor)

continue;

imsg_compose_event(&c->iev, IMSG_CTL_MONITOR, 0, 0,

-1, &type, sizeof(type));

}

}

void

control_dispatch_imsg(int fd, short event, void *bula)

{

struct ctl_conn *c;

struct imsg imsg;

struct player_repeat rp;

ssize_t n, off;

if ((c = control_connbyfd(fd)) == NULL) {

log_warnx("%s: fd %d: not found", __func__, fd);

return;

}

if (event & EV_READ) {

if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||

n == 0) {

control_close(fd);

return;

}

}

if (event & EV_WRITE) {

if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) {

control_close(fd);

return;

}

}

for (;;) {

if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {

control_close(fd);

return;

}

if (n == 0)

break;

switch (imsg.hdr.type) {

case IMSG_CTL_PLAY:

switch (play_state) {

case STATE_STOPPED:

main_playlist_resume();

break;

case STATE_PLAYING:

/* do nothing */

break;

case STATE_PAUSED:

play_state = STATE_PLAYING;

main_send_player(IMSG_RESUME, -1);

break;

}

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_TOGGLE_PLAY:

switch (play_state) {

case STATE_STOPPED:

main_playlist_resume();

break;

case STATE_PLAYING:

play_state = STATE_PAUSED;

main_send_player(IMSG_PAUSE, -1);

break;

case STATE_PAUSED:

play_state = STATE_PLAYING;

main_send_player(IMSG_RESUME, -1);

break;

}

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_PAUSE:

if (play_state != STATE_PLAYING)

break;

play_state = STATE_PAUSED;

main_send_player(IMSG_PAUSE, -1);

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_STOP:

if (play_state == STATE_STOPPED)

break;

play_state = STATE_STOPPED;

main_send_player(IMSG_STOP, -1);

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_RESTART:

main_send_player(IMSG_STOP, -1);

main_restart_track();

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_FLUSH:

playlist_truncate();

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_SHOW:

main_send_playlist(&c->iev);

break;

case IMSG_CTL_STATUS:

main_send_status(&c->iev);

break;

case IMSG_CTL_NEXT:

main_send_player(IMSG_STOP, -1);

main_playlist_advance();

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_PREV:

main_send_player(IMSG_STOP, -1);

main_playlist_previous();

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_JUMP:

main_playlist_jump(&c->iev, &imsg);

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_REPEAT:

if (IMSG_DATA_SIZE(imsg) != sizeof(rp)) {

log_warnx("%s: got wrong size", __func__);

break;

}

memcpy(&rp, imsg.data, sizeof(rp));

if (rp.repeat_all != -1)

repeat_all = rp.repeat_all;

if (rp.repeat_one != -1)

repeat_one = rp.repeat_one;

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_BEGIN:

if (control_state.tx != -1) {

main_senderr(&c->iev, "locked");

break;

}

control_state.tx = c->iev.ibuf.fd;

imsg_compose_event(&c->iev, IMSG_CTL_BEGIN, 0, 0, -1,

NULL, 0);

break;

case IMSG_CTL_ADD:

if (control_state.tx != -1 &&

control_state.tx != c->iev.ibuf.fd) {

main_senderr(&c->iev, "locked");

break;

}

main_enqueue(control_state.tx != -1,

&control_state.play,&c->iev, &imsg);

if (control_state.tx == -1)

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_COMMIT:

if (control_state.tx != c->iev.ibuf.fd) {

main_senderr(&c->iev, "locked");

break;

}

if (IMSG_DATA_SIZE(imsg) != sizeof(off)) {

main_senderr(&c->iev, "wrong size");

break;

}

memcpy(&off, imsg.data, sizeof(off));

playlist_swap(&control_state.play, off);

memset(&control_state.play, 0,

sizeof(control_state.play));

control_state.tx = -1;

imsg_compose_event(&c->iev, IMSG_CTL_COMMIT, 0, 0, -1,

NULL, 0);

control_notify(&c->iev, imsg.hdr.type);

break;

case IMSG_CTL_MONITOR:

c->monitor = 1;

break;

default:

log_debug("%s: error handling imsg %d", __func__,

imsg.hdr.type);

break;

}

imsg_free(&imsg);

}

imsg_event_add(&c->iev);

}

int

control_imsg_relay(struct imsg *imsg)

{

struct ctl_conn *c;

if ((c = control_connbypid(imsg->hdr.pid)) == NULL)

return (0);

return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,

-1, imsg->data, IMSG_DATA_SIZE(*imsg)));

}