espeakup/espeakup.c
Samuel Thibault 5339da3144 Support audio pauses
When the Linux console is e.g. switched to a graphical VT, the kernel
emits \x01P to notify that it is not able to read the screen any more,
and the software synthesis can thus release the audio card, for other
screen readers to take over.

This implements it by adding a paused_espeak variable that tracks
whether we have suspended espeak.  When more text comes, we can simply
reinitialize espeak.

This fixes #10.
2018-07-11 16:02:44 -05:00

248 lines
5.3 KiB
C

/*
* espeakup - interface which allows speakup to use espeak
*
* Copyright (C) 2008 William Hubbs
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/file.h>
#include "espeakup.h"
/* path to our pid file */
char *pidPath = "/var/run/espeakup.pid";
int debug = 0;
enum espeakup_mode_t espeakup_mode = ESPEAKUP_MODE_SPEAKUP;
struct queue_t *synth_queue = NULL;
int self_pipe_fds[2];
volatile int should_run = 1;
espeak_AUDIO_OUTPUT audio_mode;
pthread_cond_t runner_awake = PTHREAD_COND_INITIALIZER;
pthread_cond_t stop_acknowledged = PTHREAD_COND_INITIALIZER;
pthread_mutex_t queue_guard = PTHREAD_MUTEX_INITIALIZER;
int espeakup_start_daemon(void)
{
int fds[2];
pid_t pid;
char c;
if (pipe(fds) < 0) {
perror("pipe");
exit(1);
}
pid = fork();
if (pid < 0) {
perror("fork");
exit(1);
}
if (pid) {
/* Parent, just wait for daemon */
if (read(fds[0], &c, 1) < 0) {
printf("Espeakup is already running!\n");
exit(1);
}
exit(c);
}
/* Child, create new session */
setsid();
pid = fork();
if (pid)
/* Intermediate child, just exit */
exit(0);
/* Child */
if (chdir("/") < 0) {
c = 1;
(void)write(fds[1], &c, 1);
exit(1);
}
return fds[1];
}
int espeakup_is_running(void)
{
int pidFile;
int n;
char s[16];
pid_t pid;
pidFile = open(pidPath, O_RDWR | O_CREAT, 0666);
if (pidFile < 0) {
printf("Can not work with the pid file %s: %s\n", pidPath,
strerror(errno));
return -1;
}
if (flock(pidFile, LOCK_EX) < 0) {
printf("Can not lock the pid file %s: %s\n", pidPath,
strerror(errno));
goto error;
}
n = read(pidFile, s, sizeof(s) - 1);
if (n < 0) {
printf("Can not read the pid file %s: %s\n", pidPath,
strerror(errno));
goto error;
}
s[n] = 0;
n = sscanf(s, "%d", &pid);
if (n == 1 && (!kill(pid, 0) || errno != ESRCH)) {
/* Already running */
close(pidFile);
return 1;
}
if (ftruncate(pidFile, 0) < 0) {
printf("Could not truncate the pid file %s: %s\n", pidPath,
strerror(errno));
goto error;
}
lseek(pidFile, 0, SEEK_SET);
n = snprintf(s, sizeof(s), "%d", getpid());
if (write(pidFile, s, n) < 0) {
printf("Could not write to the pid file %s: %s\n", pidPath,
strerror(errno));
goto error;
}
close(pidFile);
return 0;
error:
close(pidFile);
return -1;
}
int main(int argc, char **argv)
{
int fd, devnull;
char ret = 0;
sigset_t sigset;
int err;
pthread_t signal_thread_id;
pthread_t espeak_thread_id;
pthread_t softsynth_thread_id;
struct synth_t s = {
.voice = "",
};
synth_queue = new_queue();
if (!synth_queue) {
fprintf(stderr, "Unable to allocate memory.\n");
return 2;
}
/* set up the pipe used to wake the espeak thread */
if (pipe(self_pipe_fds) < 0) {
perror("Unable to create pipe");
return 5;
}
/* process command line options */
process_cli(argc, argv);
if (!debug && espeakup_mode == ESPEAKUP_MODE_SPEAKUP) {
fd = espeakup_start_daemon();
if (espeakup_is_running()) {
printf("Espeakup is already running!\n");
ret = 1;
goto out;
}
devnull = open("/dev/null", O_RDWR);
dup2(devnull, STDIN_FILENO);
dup2(devnull, STDOUT_FILENO);
dup2(devnull, STDERR_FILENO);
if (devnull > 2)
close(devnull);
}
/* create the signal processing thread here. */
err = pthread_create(&signal_thread_id, NULL, signal_thread, NULL);
if (err != 0) {
ret = 4;
goto out;
}
/*
* Set up the signal mask which will be the default for all threads.
* We are handling sigint and sigterm, so block them.
*/
sigemptyset(&sigset);
sigaddset(&sigset, SIGINT);
sigaddset(&sigset, SIGTERM);
sigprocmask(SIG_BLOCK, &sigset, NULL);
/* Initialize espeak */
if (initialize_espeak(&s) < 0) {
ret = 2;
goto out;
}
/* open the softsynth */
if (open_softsynth() < 0) {
ret = 2;
goto out;
}
/* Spawn our softsynth thread. */
err = pthread_create(&softsynth_thread_id, NULL, softsynth_thread, &s);
if (err != 0) {
ret = 4;
goto out;
}
/* Spawn our espeak-interacting thread. */
err = pthread_create(&espeak_thread_id, NULL, espeak_thread, &s);
if (err != 0) {
ret = 4;
goto out;
}
if (!debug && espeakup_mode == ESPEAKUP_MODE_SPEAKUP)
(void)write(fd, &ret, 1);
/* wait for the threads to shut down. */
pthread_join(signal_thread_id, NULL);
pthread_join(softsynth_thread_id, NULL);
pthread_join(espeak_thread_id, NULL);
if (!paused_espeak)
espeak_Terminate();
close_softsynth();
out:
if (!debug && espeakup_mode == ESPEAKUP_MODE_SPEAKUP) {
if (ret != 1)
unlink(pidPath);
if (ret != 0)
(void)write(fd, &ret, 1);
/* If ret was 0, the status byte was written before joining
* the threads. */
}
return ret;
}