freebsd-skq/usr.sbin/watch/watch.c
dd 91fc5ccdb5 Add an -f option which allows one to specify a snp device to use.
Previously, watch would always use the first device it could
successfully open, but this isn't always desired.  Specifically, it
may not be desired during debugging (of snp), or if a particular snp
device has different permissions (which makes since after snp.c 1.64).
2001-11-24 15:41:38 +00:00

451 lines
9.0 KiB
C

/*
* Copyright (c) 1995 Ugen J.S.Antsilevich
*
* Redistribution and use in source forms, with and without modification,
* are permitted provided that this entire comment appears intact.
*
* Redistribution in binary form may occur without any restrictions.
* Obviously, it would be nice if you gave credit where credit is due
* but requiring it would be too onerous.
*
* This software is provided ``AS IS'' without any warranties of any kind.
*
* Snoop stuff.
*/
#ifndef lint
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/fcntl.h>
#include <sys/filio.h>
#include <sys/snoop.h>
#include <sys/stat.h>
#include <sys/linker.h>
#include <sys/module.h>
#include <err.h>
#include <locale.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <termcap.h>
#include <termios.h>
#include <unistd.h>
#define MSG_INIT "Snoop started."
#define MSG_OFLOW "Snoop stopped due to overflow. Reconnecting."
#define MSG_CLOSED "Snoop stopped due to tty close. Reconnecting."
#define MSG_CHANGE "Snoop device change by user request."
#define MSG_NOWRITE "Snoop device change due to write failure."
#define DEV_NAME_LEN 1024 /* for /dev/ttyXX++ */
#define MIN_SIZE 256
#define CHR_SWITCH 24 /* Ctrl+X */
#define CHR_CLEAR 23 /* Ctrl+V */
static void clear __P((void));
static void timestamp __P((const char *));
static void set_tty __P((void));
static void unset_tty __P((void));
static void fatal __P((int, const char *));
static int open_snp __P((void));
static void cleanup __P((int));
static void usage __P((void));
static void setup_scr __P((void));
static void attach_snp __P((void));
static void detach_snp __P((void));
static void set_dev __P((const char *));
static void ask_dev __P((char *, const char *));
int opt_reconn_close = 0;
int opt_reconn_oflow = 0;
int opt_interactive = 1;
int opt_timestamp = 0;
int opt_write = 0;
int opt_no_switch = 0;
const char *opt_snpdev;
char dev_name[DEV_NAME_LEN];
int snp_io;
dev_t snp_tty;
int std_in = 0, std_out = 1;
int clear_ok = 0;
struct termios otty;
char tbuf[1024], gbuf[1024];
static void
clear()
{
if (clear_ok)
tputs(gbuf, 1, putchar);
fflush(stdout);
}
static void
timestamp(buf)
const char *buf;
{
time_t t;
char btmp[1024];
clear();
printf("\n---------------------------------------------\n");
t = time(NULL);
strftime(btmp, 1024, "Time: %d %b %H:%M", localtime(&t));
printf("%s\n", btmp);
printf("%s\n", buf);
printf("---------------------------------------------\n");
fflush(stdout);
}
static void
set_tty()
{
struct termios ntty;
tcgetattr (std_in, &otty);
ntty = otty;
ntty.c_lflag &= ~ICANON; /* disable canonical operation */
ntty.c_lflag &= ~ECHO;
#ifdef FLUSHO
ntty.c_lflag &= ~FLUSHO;
#endif
#ifdef PENDIN
ntty.c_lflag &= ~PENDIN;
#endif
#ifdef IEXTEN
ntty.c_lflag &= ~IEXTEN;
#endif
ntty.c_cc[VMIN] = 1; /* minimum of one character */
ntty.c_cc[VTIME] = 0; /* timeout value */
ntty.c_cc[VINTR] = 07; /* ^G */
ntty.c_cc[VQUIT] = 07; /* ^G */
tcsetattr (std_in, TCSANOW, &ntty);
}
static void
unset_tty()
{
tcsetattr (std_in, TCSANOW, &otty);
}
static void
fatal(error, buf)
int error;
const char *buf;
{
unset_tty();
if (buf)
errx(error, "fatal: %s", buf);
else
exit(error);
}
static int
open_snp()
{
char snp[] = {_PATH_DEV "snpX"};
char c;
int f, mode;
if (opt_write)
mode = O_RDWR;
else
mode = O_RDONLY;
if (opt_snpdev == NULL)
for (c = '0'; c <= '9'; c++) {
snp[8] = c;
if ((f = open(snp, mode)) < 0)
continue;
return f;
}
else
if ((f = open(opt_snpdev, mode)) != -1)
return (f);
fatal(EX_OSFILE, "cannot open snoop device");
return (0);
}
static void
cleanup(signo)
int signo __unused;
{
if (opt_timestamp)
timestamp("Logging Exited.");
close(snp_io);
unset_tty();
exit(EX_OK);
}
static void
usage()
{
fprintf(stderr, "usage: watch [-ciotnW] [tty name]\n");
exit(EX_USAGE);
}
static void
setup_scr()
{
char *cbuf = gbuf, *term;
if (!opt_interactive)
return;
if ((term = getenv("TERM")))
if (tgetent(tbuf, term) == 1)
if (tgetstr("cl", &cbuf))
clear_ok = 1;
set_tty();
clear();
}
static void
detach_snp()
{
dev_t dev;
dev = NODEV;
ioctl(snp_io, SNPSTTY, &dev);
}
static void
attach_snp()
{
if (ioctl(snp_io, SNPSTTY, &snp_tty) != 0)
fatal(EX_UNAVAILABLE, "cannot attach to tty");
if (opt_timestamp)
timestamp("Logging Started.");
}
static void
set_dev(name)
const char *name;
{
char buf[DEV_NAME_LEN];
struct stat sb;
if (strlen(name) > 5 && !strncmp(name, _PATH_DEV, sizeof _PATH_DEV - 1)) {
snprintf(buf, sizeof buf, "%s", name);
}
else {
if (strlen(name) == 2)
sprintf(buf, "%s%s", _PATH_TTY, name);
else
sprintf(buf, "%s%s", _PATH_DEV, name);
}
if (*name == '\0' || stat(buf, &sb) < 0)
fatal(EX_DATAERR, "bad device name");
if ((sb.st_mode & S_IFMT) != S_IFCHR)
fatal(EX_DATAERR, "must be a character device");
snp_tty = sb.st_rdev;
attach_snp();
}
void
ask_dev(dbuf, msg)
char *dbuf;
const char *msg;
{
char buf[DEV_NAME_LEN];
int len;
clear();
unset_tty();
if (msg)
printf("%s\n", msg);
if (dbuf)
printf("Enter device name [%s]:", dbuf);
else
printf("Enter device name:");
if (fgets(buf, DEV_NAME_LEN - 1, stdin)) {
len = strlen(buf);
if (buf[len - 1] == '\n')
buf[len - 1] = '\0';
if (buf[0] != '\0' && buf[0] != ' ')
strcpy(dbuf, buf);
}
set_tty();
}
#define READB_LEN 5
int
main(ac, av)
int ac;
char **av;
{
int res, idata, rv;
size_t nread, b_size = MIN_SIZE;
char ch, *buf, chb[READB_LEN];
fd_set fd_s;
(void) setlocale(LC_TIME, "");
if (isatty(std_out))
opt_interactive = 1;
else
opt_interactive = 0;
while ((ch = getopt(ac, av, "Wciotnf:")) != -1)
switch (ch) {
case 'W':
opt_write = 1;
break;
case 'c':
opt_reconn_close = 1;
break;
case 'i':
opt_interactive = 1;
break;
case 'o':
opt_reconn_oflow = 1;
break;
case 't':
opt_timestamp = 1;
break;
case 'n':
opt_no_switch = 1;
break;
case 'f':
opt_snpdev = optarg;
break;
case '?':
default:
usage();
}
if (modfind("snp") == -1)
if (kldload("snp") == -1 || modfind("snp") == -1)
warn("snp module not available");
signal(SIGINT, cleanup);
setup_scr();
snp_io = open_snp();
if (*(av += optind) == NULL) {
if (opt_interactive && !opt_no_switch)
ask_dev(dev_name, MSG_INIT);
else
fatal(EX_DATAERR, "no device name given");
} else
strncpy(dev_name, *av, DEV_NAME_LEN);
set_dev(dev_name);
if (!(buf = (char *) malloc(b_size)))
fatal(EX_UNAVAILABLE, "malloc failed");
FD_ZERO(&fd_s);
while (1) {
if (opt_interactive)
FD_SET(std_in, &fd_s);
FD_SET(snp_io, &fd_s);
res = select(snp_io + 1, &fd_s, NULL, NULL, NULL);
if (opt_interactive && FD_ISSET(std_in, &fd_s)) {
if ((res = ioctl(std_in, FIONREAD, &nread)) != 0)
fatal(EX_OSERR, "ioctl(FIONREAD)");
if (nread > READB_LEN)
nread = READB_LEN;
rv = read(std_in, chb, nread);
if (rv == -1 || (unsigned)rv != nread)
fatal(EX_IOERR, "read (stdin) failed");
switch (chb[0]) {
case CHR_CLEAR:
clear();
break;
case CHR_SWITCH:
if (!opt_no_switch) {
detach_snp();
ask_dev(dev_name, MSG_CHANGE);
set_dev(dev_name);
break;
}
default:
if (opt_write) {
rv = write(snp_io, chb, nread);
if (rv == -1 || (unsigned)rv != nread) {
detach_snp();
if (opt_no_switch)
fatal(EX_IOERR, "write failed");
ask_dev(dev_name, MSG_NOWRITE);
set_dev(dev_name);
}
}
}
}
if (!FD_ISSET(snp_io, &fd_s))
continue;
if ((res = ioctl(snp_io, FIONREAD, &idata)) != 0)
fatal(EX_OSERR, "ioctl(FIONREAD)");
switch (idata) {
case SNP_OFLOW:
if (opt_reconn_oflow)
attach_snp();
else if (opt_interactive && !opt_no_switch) {
ask_dev(dev_name, MSG_OFLOW);
set_dev(dev_name);
} else
cleanup(-1);
case SNP_DETACH:
case SNP_TTYCLOSE:
if (opt_reconn_close)
attach_snp();
else if (opt_interactive && !opt_no_switch) {
ask_dev(dev_name, MSG_CLOSED);
set_dev(dev_name);
} else
cleanup(-1);
default:
nread = (unsigned)idata;
if (nread < (b_size / 2) && (b_size / 2) > MIN_SIZE) {
free(buf);
if (!(buf = (char *) malloc(b_size / 2)))
fatal(EX_UNAVAILABLE, "malloc failed");
b_size = b_size / 2;
}
if (nread > b_size) {
b_size = (nread % 2) ? (nread + 1) : (nread);
free(buf);
if (!(buf = (char *) malloc(b_size)))
fatal(EX_UNAVAILABLE, "malloc failed");
}
rv = read(snp_io, buf, nread);
if (rv == -1 || (unsigned)rv != nread)
fatal(EX_IOERR, "read failed");
rv = write(std_out, buf, nread);
if (rv == -1 || (unsigned)rv != nread)
fatal(EX_IOERR, "write failed");
}
} /* While */
return(0);
}