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-rw-r--r--miscutils/microcom.c153
1 files changed, 71 insertions, 82 deletions
diff --git a/miscutils/microcom.c b/miscutils/microcom.c
index 00a49837e..fb5e9c868 100644
--- a/miscutils/microcom.c
+++ b/miscutils/microcom.c
@@ -17,7 +17,7 @@ static void signal_handler(int signo)
signalled = signo;
}
-// set canonical tty mode
+// set raw tty mode
static void xget1(int fd, struct termios *t, struct termios *oldt)
{
tcgetattr(fd, oldt);
@@ -32,7 +32,7 @@ static void xget1(int fd, struct termios *t, struct termios *oldt)
static int xset1(int fd, struct termios *tio, const char *device)
{
- int ret = tcsetattr(fd, TCSANOW, tio);
+ int ret = tcsetattr(fd, TCSAFLUSH, tio);
if (ret) {
bb_perror_msg("can't tcsetattr for %s", device);
@@ -43,41 +43,45 @@ static int xset1(int fd, struct termios *tio, const char *device)
int microcom_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int microcom_main(int argc, char **argv)
{
- struct pollfd pfd[2];
- int nfd;
int sfd;
-/* #define sfd (pfd[0].fd) - gcc 4.2.1 is still not smart enough */
- char *device_lock_file;
- const char *opt_s = "9600";
- speed_t speed;
- const char *opt_t = "100"; // 0.1 sec timeout
- unsigned timeout;
+ int nfd;
+ struct pollfd pfd[2];
struct termios tio0, tiosfd, tio;
- bool istty;
+ char *device_lock_file;
+ enum {
+ OPT_X = 1 << 0, // do not respect Ctrl-X, Ctrl-@
+ OPT_s = 1 << 1, // baudrate
+ OPT_t = 1 << 2 // wait for device response, msecs
+ };
+ speed_t speed = 9600;
+ int timeout = 100; // 0.1 sec timeout
// fetch options
- opt_complementary = "-1"; /* at least one arg should be there */
- getopt32(argv, "s:t:", &opt_s, &opt_t);
- argc -= optind;
+ char *opt_s;
+ char *opt_t;
+ unsigned opts;
+ opt_complementary = "=1"; /* exactly one arg should be there */
+ opts = getopt32(argv, "Xs:t:", &opt_s, &opt_t);
+ // apply options
+ if (opts & OPT_s)
+ speed = xatoi_u(opt_s);
+ if (opts & OPT_t)
+ timeout = xatoi_u(opt_t);
+// argc -= optind;
argv += optind;
- // check sanity
- speed = xatou(opt_s);
- timeout = xatou(opt_t);
- device_lock_file = (char *)bb_basename(argv[0]);
-
// try to create lock file in /var/lock
+ device_lock_file = (char *)bb_basename(argv[0]);
device_lock_file = xasprintf("/var/lock/LCK..%s", device_lock_file);
sfd = open(device_lock_file, O_CREAT | O_WRONLY | O_TRUNC | O_EXCL, 0644);
if (sfd < 0) {
if (errno == EEXIST)
- bb_perror_msg_and_die("can't lock device");
- // We don't abort on other errors: /var/lock can be
- // non-writable or non-existent
+ bb_perror_msg_and_die("can't create %s", device_lock_file);
if (ENABLE_FEATURE_CLEAN_UP)
free(device_lock_file);
device_lock_file = NULL;
- } else {
+ }
+ if (sfd > 0) {
// %4d to make mgetty happy. It treats 4-bytes lock files as binary,
// not text, PID. Making 5+ char file. Brrr...
char *s = xasprintf("%4d\n", getpid());
@@ -99,17 +103,15 @@ int microcom_main(int argc, char **argv)
// open device
sfd = open_or_warn(argv[0], O_RDWR | O_NOCTTY | O_NONBLOCK);
if (sfd < 0)
- goto unlock_and_exit;
+ goto done;
fcntl(sfd, F_SETFL, O_RDWR | O_NOCTTY);
/* put stdin to "raw mode" (if stdin is a TTY),
handle one character at a time */
- istty = isatty(STDIN_FILENO);
- if (istty) {
+ if (isatty(STDIN_FILENO)) {
xget1(STDIN_FILENO, &tio, &tio0);
if (xset1(STDIN_FILENO, &tio, "stdin"))
- goto close_unlock_and_exit;
-// tcflush(STDIN_FILENO, TCIFLUSH);
+ goto done;
timeout = -1; // tty input? -> set infinite timeout for poll()
}
@@ -117,10 +119,12 @@ int microcom_main(int argc, char **argv)
xget1(sfd, &tio, &tiosfd);
// order device to hang up at exit
tio.c_cflag |= (CREAD|HUPCL);
+// if (!istty)
+// tio.c_iflag |= (IGNCR);
// set device speed
cfsetspeed(&tio, tty_value_to_baud(speed));
if (xset1(sfd, &tio, argv[0]))
- goto restore0_close_unlock_and_exit;
+ goto restore0_and_done;
// main loop: check with poll(), then read/write bytes across
pfd[0].fd = sfd;
@@ -128,69 +132,54 @@ int microcom_main(int argc, char **argv)
pfd[1].fd = STDIN_FILENO;
pfd[1].events = POLLIN;
- // TODO: on piped input should we treat NL as CRNL?!
-
signalled = 0;
- // initially we have to poll() both stdin and device
nfd = 2;
- while (!signalled && nfd && safe_poll(pfd, nfd, timeout) > 0) {
- int i;
-
- for (i = 0; i < nfd; ++i) {
- if (pfd[i].revents & (POLLIN | POLLHUP)) {
-// int fd;
- char c;
- // read a byte
- if (safe_read(pfd[i].fd, &c, 1) < 1) {
- // this can occur at the end of piped input
- // from now we only poll() for device
- nfd--;
+ while (!signalled && safe_poll(pfd, nfd, timeout) > 0) {
+ char c;
+ if (pfd[0].revents & POLLIN) {
+ // read from device -> write to stdout
+ if (safe_read(sfd, &c, 1) > 0)
+ write(STDOUT_FILENO, &c, 1);
+ }
+ if (pfd[1].revents & POLLIN) {
+ // read from stdin -> write to device
+ if (safe_read(STDIN_FILENO, &c, 1) < 1) {
+ // skip polling stdin if we got EOF/error
+ pfd[1].revents = 0;
+ nfd--;
+ continue;
+ }
+ // do we need special processing?
+ if (!(opts & OPT_X)) {
+ // ^@ sends Break
+ if (VINTR == c) {
+ tcsendbreak(sfd, 0);
continue;
}
-// fd = STDOUT_FILENO;
- // stdin requires additional processing
- // (TODO: must be controlled by command line switch)
- if (i) {
- // ^@ sends Break
- if (0 == c) {
- tcsendbreak(sfd, 0);
- continue;
- }
- // ^X exits
- if (24 == c)
- goto done;
-// fd = sfd;
- }
- // write the byte
- write(i ? sfd : STDOUT_FILENO, &c, 1);
-// write(fd, &c, 1);
- // give device a chance to get data
- // wait 0.01 msec
- // (TODO: seems to be arbitrary to me)
- if (i)
- usleep(10);
+ // ^X exits
+ if (24 == c)
+ break;
}
+ write(sfd, &c, 1);
+//// vda: this is suspicious!
+ // without this we never get POLLIN on sfd
+ // until piped stdin is drained
+ if (-1 != timeout)
+ safe_poll(pfd, 1, 1 /* 1 ms */);
}
}
-done:
- tcsetattr(sfd, TCSANOW, &tiosfd);
+ /* usleep(10000); - let last chars leave serial line */
-restore0_close_unlock_and_exit:
- if (istty) {
-// tcflush(STDIN_FILENO, TCIFLUSH);
- tcsetattr(STDIN_FILENO, TCSANOW, &tio0);
- }
+ tcsetattr(sfd, TCSAFLUSH, &tiosfd);
-close_unlock_and_exit:
- if (ENABLE_FEATURE_CLEAN_UP)
- close(sfd);
+restore0_and_done:
+ // timeout == -1 -- stdin is a tty
+ if (-1 == timeout)
+ tcsetattr(STDIN_FILENO, TCSAFLUSH, &tio0);
-unlock_and_exit:
- // delete lock file
- if (device_lock_file) {
+done:
+ if (device_lock_file)
unlink(device_lock_file);
- if (ENABLE_FEATURE_CLEAN_UP)
- free(device_lock_file);
- }
+
return signalled;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 02:22:32 +0000