diff options
Diffstat (limited to 'usr.bin/write/write.c')
-rw-r--r-- | usr.bin/write/write.c | 328 |
1 files changed, 0 insertions, 328 deletions
diff --git a/usr.bin/write/write.c b/usr.bin/write/write.c deleted file mode 100644 index 878c8c1..0000000 --- a/usr.bin/write/write.c +++ /dev/null @@ -1,328 +0,0 @@ -/* - * Copyright (c) 1989, 1993 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software contributed to Berkeley by - * Jef Poskanzer and Craig Leres of the Lawrence Berkeley Laboratory. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#ifndef lint -static const char copyright[] = -"@(#) Copyright (c) 1989, 1993\n\ - The Regents of the University of California. All rights reserved.\n"; -#endif - -#if 0 -#ifndef lint -static char sccsid[] = "@(#)write.c 8.1 (Berkeley) 6/6/93"; -#endif -#endif - -#include <sys/cdefs.h> -__FBSDID("$FreeBSD$"); - -#include <sys/param.h> -#include <sys/signal.h> -#include <sys/stat.h> -#include <sys/file.h> -#include <sys/time.h> -#include <ctype.h> -#include <err.h> -#include <locale.h> -#include <paths.h> -#include <pwd.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#include <utmp.h> - -void done(int); -void do_write(char *, char *, uid_t); -static void usage(void); -int term_chk(char *, int *, time_t *, int); -void wr_fputs(unsigned char *s); -void search_utmp(char *, char *, char *, uid_t); -int utmp_chk(char *, char *); - -int -main(int argc, char **argv) -{ - time_t atime; - uid_t myuid; - int msgsok, myttyfd; - char tty[MAXPATHLEN], *mytty; - - (void)setlocale(LC_CTYPE, ""); - - while (getopt(argc, argv, "") != -1) - usage(); - argc -= optind; - argv += optind; - - /* check that sender has write enabled */ - if (isatty(fileno(stdin))) - myttyfd = fileno(stdin); - else if (isatty(fileno(stdout))) - myttyfd = fileno(stdout); - else if (isatty(fileno(stderr))) - myttyfd = fileno(stderr); - else - errx(1, "can't find your tty"); - if (!(mytty = ttyname(myttyfd))) - errx(1, "can't find your tty's name"); - if (!strncmp(mytty, _PATH_DEV, strlen(_PATH_DEV))) - mytty += strlen(_PATH_DEV); - if (term_chk(mytty, &msgsok, &atime, 1)) - exit(1); - if (!msgsok) - errx(1, "you have write permission turned off"); - - myuid = getuid(); - - /* check args */ - switch (argc) { - case 1: - search_utmp(argv[0], tty, mytty, myuid); - do_write(tty, mytty, myuid); - break; - case 2: - if (!strncmp(argv[1], _PATH_DEV, strlen(_PATH_DEV))) - argv[1] += strlen(_PATH_DEV); - if (utmp_chk(argv[0], argv[1])) - errx(1, "%s is not logged in on %s", argv[0], argv[1]); - if (term_chk(argv[1], &msgsok, &atime, 1)) - exit(1); - if (myuid && !msgsok) - errx(1, "%s has messages disabled on %s", argv[0], argv[1]); - do_write(argv[1], mytty, myuid); - break; - default: - usage(); - } - done(0); - return (0); -} - -static void -usage(void) -{ - (void)fprintf(stderr, "usage: write user [tty]\n"); - exit(1); -} - -/* - * utmp_chk - checks that the given user is actually logged in on - * the given tty - */ -int -utmp_chk(char *user, char *tty) -{ - struct utmp u; - int ufd; - - if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0) - return(0); /* ignore error, shouldn't happen anyway */ - - while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u)) - if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0 && - strncmp(tty, u.ut_line, sizeof(u.ut_line)) == 0) { - (void)close(ufd); - return(0); - } - - (void)close(ufd); - return(1); -} - -/* - * search_utmp - search utmp for the "best" terminal to write to - * - * Ignores terminals with messages disabled, and of the rest, returns - * the one with the most recent access time. Returns as value the number - * of the user's terminals with messages enabled, or -1 if the user is - * not logged in at all. - * - * Special case for writing to yourself - ignore the terminal you're - * writing from, unless that's the only terminal with messages enabled. - */ -void -search_utmp(char *user, char *tty, char *mytty, uid_t myuid) -{ - struct utmp u; - time_t bestatime, atime; - int ufd, nloggedttys, nttys, msgsok, user_is_me; - char atty[UT_LINESIZE + 1]; - - if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0) - err(1, "utmp"); - - nloggedttys = nttys = 0; - bestatime = 0; - user_is_me = 0; - while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u)) - if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0) { - ++nloggedttys; - (void)strncpy(atty, u.ut_line, UT_LINESIZE); - atty[UT_LINESIZE] = '\0'; - if (term_chk(atty, &msgsok, &atime, 0)) - continue; /* bad term? skip */ - if (myuid && !msgsok) - continue; /* skip ttys with msgs off */ - if (strcmp(atty, mytty) == 0) { - user_is_me = 1; - continue; /* don't write to yourself */ - } - ++nttys; - if (atime > bestatime) { - bestatime = atime; - (void)strcpy(tty, atty); - } - } - - (void)close(ufd); - if (nloggedttys == 0) - errx(1, "%s is not logged in", user); - if (nttys == 0) { - if (user_is_me) { /* ok, so write to yourself! */ - (void)strcpy(tty, mytty); - return; - } - errx(1, "%s has messages disabled", user); - } else if (nttys > 1) { - warnx("%s is logged in more than once; writing to %s", user, tty); - } -} - -/* - * term_chk - check that a terminal exists, and get the message bit - * and the access time - */ -int -term_chk(char *tty, int *msgsokP, time_t *atimeP, int showerror) -{ - struct stat s; - char path[MAXPATHLEN]; - - (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty); - if (stat(path, &s) < 0) { - if (showerror) - warn("%s", path); - return(1); - } - *msgsokP = (s.st_mode & (S_IWRITE >> 3)) != 0; /* group write bit */ - *atimeP = s.st_atime; - return(0); -} - -/* - * do_write - actually make the connection - */ -void -do_write(char *tty, char *mytty, uid_t myuid) -{ - const char *login; - char *nows; - struct passwd *pwd; - time_t now; - char path[MAXPATHLEN], host[MAXHOSTNAMELEN], line[512]; - - /* Determine our login name before we reopen() stdout */ - if ((login = getlogin()) == NULL) { - if ((pwd = getpwuid(myuid))) - login = pwd->pw_name; - else - login = "???"; - } - - (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty); - if ((freopen(path, "w", stdout)) == NULL) - err(1, "%s", path); - - (void)signal(SIGINT, done); - (void)signal(SIGHUP, done); - - /* print greeting */ - if (gethostname(host, sizeof(host)) < 0) - (void)strcpy(host, "???"); - now = time((time_t *)NULL); - nows = ctime(&now); - nows[16] = '\0'; - (void)printf("\r\n\007\007\007Message from %s@%s on %s at %s ...\r\n", - login, host, mytty, nows + 11); - - while (fgets(line, sizeof(line), stdin) != NULL) - wr_fputs(line); -} - -/* - * done - cleanup and exit - */ -void -done(int n __unused) -{ - (void)printf("EOF\r\n"); - exit(0); -} - -/* - * wr_fputs - like fputs(), but makes control characters visible and - * turns \n into \r\n - */ -void -wr_fputs(unsigned char *s) -{ - -#define PUTC(c) if (putchar(c) == EOF) err(1, NULL); - - for (; *s != '\0'; ++s) { - if (*s == '\n') { - PUTC('\r'); - } else if (((*s & 0x80) && *s < 0xA0) || - /* disable upper controls */ - (!isprint(*s) && !isspace(*s) && - *s != '\a' && *s != '\b') - ) { - if (*s & 0x80) { - *s &= ~0x80; - PUTC('M'); - PUTC('-'); - } - if (iscntrl(*s)) { - *s ^= 0x40; - PUTC('^'); - } - } - PUTC(*s); - } - return; -#undef PUTC -} |