/*
* Simple serial terminal
*
- * Copyright 2014 Michal Sojka <sojkam1@fel.cvut.cz>
+ * Copyright 2014, 2015 Michal Sojka <sojkam1@fel.cvut.cz>
*
* This program is free software: you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
#define _BSD_SOURCE
#include <sys/ioctl.h>
+#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <termios.h>
#include <stdbool.h>
#include <string.h>
#include <signal.h>
+#include <lockdev.h>
#define STRINGIFY(val) #val
#define TOSTRING(val) STRINGIFY(val)
bool verbose = false;
bool exit_on_escape = true;
-char template[] = "/var/lock/TMPXXXXXX";
-char lockfile[100];
struct termios stdin_tio_backup;
+char *dev = NULL;
void rm_file(int status, void *arg)
{
tcsetattr(0, TCSANOW, &stdin_tio_backup);
}
+void unlock()
+{
+ dev_unlock(dev, getpid());
+}
+
void sighandler(int arg)
{
exit(0); /* Invoke exit handlers */
int val = -1;
if (optarg) {
- switch (optarg[0]) {
- case '+': val = +1; break;
- case '-': val = -1; break;
- default:
- fprintf(stderr, "Unknown -%c argument: %s", option, optarg);
- exit(1);
+ char *end;
+ val = strtol(optarg, &end, 10);
+ if (end == optarg) {
+ /* Not a number */
+ switch (optarg[0]) {
+ case '+': val = +1; break;
+ case '-': val = -1; break;
+ default:
+ fprintf(stderr, "Unknown -%c argument: %s", option, optarg);
+ exit(1);
+ }
}
}
return val;
static const char escseq[] = "\r~.";
static const char *state = escseq+1;
int i;
-
for (i = 0; i < len; i++) {
if (buf[i] == *state) {
state++;
if (*state == 0)
exit(0);
- } else
+ } else {
state = escseq;
+ if (buf[i] == *state)
+ state++;
+ }
}
}
void usage(const char* argv0)
{
fprintf(stderr, "Usage: %s [options] <device>\n", argv0);
- fprintf(stderr, "Options:\n");
- fprintf(stderr, " -d [+|-] create short positive/negative pulse on DTR\n");
- fprintf(stderr, " -e ignore '~.' escape sequence\n");
- fprintf(stderr, " -n do not switch the device to raw mode\n");
- fprintf(stderr, " -r [+|-] create short positive/negative pulse on RTS\n");
- fprintf(stderr, " -s <baudrate>\n");
- fprintf(stderr, " -v verbose\n");
+ fprintf(stderr,
+ "Options:\n"
+ " -d[PULSE] make pulse on DTR\n"
+ " -e ignore '~.' escape sequence\n"
+ " -n do not switch the device to raw mode\n"
+ " -r[PULSE] make pulse on RTS\n"
+ " -s <baudrate>\n"
+ "\n"
+ "PULSE is a number specifying the pulse. Absolute value defines the\n"
+ "length of the pulse in milliseconds, sign determines the polarity of\n"
+ "the pulse. Alternatively, PULSE can be either '+' or '-', which\n"
+ "corresponds to +1 or -1.\n"
+ );
}
int main(int argc, char *argv[])
{
int fd;
- char *dev = NULL;
int opt;
speed_t speed = 0;
int dtr = 0, rts = 0;
signal(SIGTERM, sighandler);
signal(SIGHUP, sighandler);
- if (strncmp(dev, "/dev/", 5) == 0 &&
- strrchr(dev, '/') == dev + 4 &&
- dev[5] != 0)
- { /* Create lock file (to be inter-operable with other programs) */
- /* This is racy, but what we can do - see also comments in uucp / cu */
- int tmp = CHECK(mkstemp(template));
- on_exit(rm_file, template);
- char pid[20];
- snprintf(pid, sizeof(pid), "%u", getpid());
- CHECK(write(tmp, pid, strlen(pid)));
- close(tmp);
- snprintf(lockfile, sizeof(lockfile), "/var/lock/LCK..%s", dev + 5);
- retry:
- if (link(template, lockfile) == -1) {
- tmp = CHECK(open(lockfile, O_RDONLY));
- CHECK(read(tmp, pid, sizeof(pid)));
- close(tmp);
- int p = atoi(pid);
- char proc[50];
- snprintf(proc, sizeof(proc), "/proc/%d", p);
- if (access(proc, F_OK) == 0) {
- fprintf(stderr, "%s is used by PID %d\n", dev, p);
- exit(1);
- }
- fprintf(stderr, "Stale lock file %s (PID %d) - removing it!\n", lockfile, p);
- CHECK(unlink(lockfile));
- goto retry;
- }
- rm_file(0, template);
- on_exit(rm_file, lockfile);
+ pid_t pid = dev_lock(dev);
+ if (pid > 0) {
+ fprintf(stderr, "%s is used by PID %d\n", dev, pid);
+ exit(1);
+ } else if (pid < 0) {
+ perror("dev_lock()");
+ exit(1);
}
+ atexit(unlock);
- if ((fd = open(dev, O_RDWR)) < 0) {
+ /* O_NONBLOCK is needed to not wait for the CDC signal. See tty_ioctl(4). */
+ if ((fd = open(dev, O_RDWR|O_NOCTTY|O_NONBLOCK)) < 0) {
perror(dev);
exit(1);
}
+ /* Cancel the efect of O_NONBLOCK flag. */
+ int n = fcntl(fd, F_GETFL, 0);
+ fcntl(fd, F_SETFL, n & ~O_NDELAY);
if (isatty(fd)) {
CHECK(ioctl(fd, TIOCEXCL, NULL));
}
if (dtr || rts) {
- int status;
+ int status, ms = 0;
/* tio.c_cflag &= ~HUPCL; */ /* Don't lower DTR/RTS on close */
CHECK(ioctl(fd, TIOCMGET, &status));
- if (dtr == -1) status &= ~TIOCM_DTR;
- if (dtr == +1) status |= TIOCM_DTR;
- if (rts == -1) status &= ~TIOCM_RTS;
- if (rts == +1) status |= TIOCM_RTS;
+ if (dtr > 0) { status &= ~TIOCM_DTR; ms = +dtr; }
+ if (dtr < 0) { status |= TIOCM_DTR; ms = -dtr; }
+ if (rts > 0) { status &= ~TIOCM_RTS; ms = +rts; }
+ if (rts < 0) { status |= TIOCM_RTS; ms = -rts; }
CHECK(ioctl(fd, TIOCMSET, &status));
+
+ usleep(ms*1000);
+
+ if (dtr < 0) { status &= ~TIOCM_DTR; }
+ if (dtr > 0) { status |= TIOCM_DTR; }
+ if (rts < 0) { status &= ~TIOCM_RTS; }
+ if (rts > 0) { status |= TIOCM_RTS; }
+ CHECK(ioctl(fd, TIOCMSET, &status));
+
}
+ /* Disable flow control */
+ tio.c_cflag &= ~(CRTSCTS);
+ tio.c_iflag &= ~(IXON|IXOFF);
+
CHECK(tcsetattr(fd, TCSANOW, &tio));
} else if (speed || dtr || rts) {
fprintf(stderr, "Cannot set speed, DTR or RTS on non-terminal %s\n", dev);
projects / sojka / sterm.git / blobdiff