1/* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Jef Poskanzer and Craig Leres of the Lawrence Berkeley Laboratory. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#ifndef lint 38static const char copyright[] = 39"@(#) Copyright (c) 1989, 1993\n\ 40 The Regents of the University of California. All rights reserved.\n"; 41#endif 42 43#if 0 44#ifndef lint 45static char sccsid[] = "@(#)write.c 8.1 (Berkeley) 6/6/93"; 46#endif 47#endif 48 49#include <sys/cdefs.h>
| 1/* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Jef Poskanzer and Craig Leres of the Lawrence Berkeley Laboratory. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#ifndef lint 38static const char copyright[] = 39"@(#) Copyright (c) 1989, 1993\n\ 40 The Regents of the University of California. All rights reserved.\n"; 41#endif 42 43#if 0 44#ifndef lint 45static char sccsid[] = "@(#)write.c 8.1 (Berkeley) 6/6/93"; 46#endif 47#endif 48 49#include <sys/cdefs.h>
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50__FBSDID("$FreeBSD: head/usr.bin/write/write.c 173572 2007-11-12 20:02:21Z jhb $");
| 50__FBSDID("$FreeBSD: head/usr.bin/write/write.c 200160 2009-12-05 20:22:26Z ed $");
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51 52#include <sys/param.h> 53#include <sys/signal.h> 54#include <sys/stat.h> 55#include <sys/file.h> 56#include <sys/time.h> 57#include <ctype.h> 58#include <err.h> 59#include <locale.h> 60#include <paths.h> 61#include <pwd.h> 62#include <stdio.h> 63#include <stdlib.h> 64#include <string.h>
| 51 52#include <sys/param.h> 53#include <sys/signal.h> 54#include <sys/stat.h> 55#include <sys/file.h> 56#include <sys/time.h> 57#include <ctype.h> 58#include <err.h> 59#include <locale.h> 60#include <paths.h> 61#include <pwd.h> 62#include <stdio.h> 63#include <stdlib.h> 64#include <string.h>
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| 65#define _ULOG_POSIX_NAMES 66#include <ulog.h>
|
65#include <unistd.h>
| 67#include <unistd.h>
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66#include <utmp.h>
| |
67 68void done(int); 69void do_write(char *, char *, uid_t); 70static void usage(void); 71int term_chk(char *, int *, time_t *, int); 72void wr_fputs(unsigned char *s); 73void search_utmp(char *, char *, char *, uid_t); 74int utmp_chk(char *, char *); 75 76int 77main(int argc, char **argv) 78{ 79 time_t atime; 80 uid_t myuid; 81 int msgsok, myttyfd; 82 char tty[MAXPATHLEN], *mytty; 83 84 (void)setlocale(LC_CTYPE, ""); 85 86 while (getopt(argc, argv, "") != -1) 87 usage(); 88 argc -= optind; 89 argv += optind; 90 91 /* check that sender has write enabled */ 92 if (isatty(fileno(stdin))) 93 myttyfd = fileno(stdin); 94 else if (isatty(fileno(stdout))) 95 myttyfd = fileno(stdout); 96 else if (isatty(fileno(stderr))) 97 myttyfd = fileno(stderr); 98 else 99 errx(1, "can't find your tty"); 100 if (!(mytty = ttyname(myttyfd))) 101 errx(1, "can't find your tty's name"); 102 if (!strncmp(mytty, _PATH_DEV, strlen(_PATH_DEV))) 103 mytty += strlen(_PATH_DEV); 104 if (term_chk(mytty, &msgsok, &atime, 1)) 105 exit(1); 106 if (!msgsok) 107 errx(1, "you have write permission turned off"); 108 109 myuid = getuid(); 110 111 /* check args */ 112 switch (argc) { 113 case 1: 114 search_utmp(argv[0], tty, mytty, myuid); 115 do_write(tty, mytty, myuid); 116 break; 117 case 2: 118 if (!strncmp(argv[1], _PATH_DEV, strlen(_PATH_DEV))) 119 argv[1] += strlen(_PATH_DEV); 120 if (utmp_chk(argv[0], argv[1])) 121 errx(1, "%s is not logged in on %s", argv[0], argv[1]); 122 if (term_chk(argv[1], &msgsok, &atime, 1)) 123 exit(1); 124 if (myuid && !msgsok) 125 errx(1, "%s has messages disabled on %s", argv[0], argv[1]); 126 do_write(argv[1], mytty, myuid); 127 break; 128 default: 129 usage(); 130 } 131 done(0); 132 return (0); 133} 134 135static void 136usage(void) 137{ 138 (void)fprintf(stderr, "usage: write user [tty]\n"); 139 exit(1); 140} 141 142/* 143 * utmp_chk - checks that the given user is actually logged in on 144 * the given tty 145 */ 146int 147utmp_chk(char *user, char *tty) 148{
| 68 69void done(int); 70void do_write(char *, char *, uid_t); 71static void usage(void); 72int term_chk(char *, int *, time_t *, int); 73void wr_fputs(unsigned char *s); 74void search_utmp(char *, char *, char *, uid_t); 75int utmp_chk(char *, char *); 76 77int 78main(int argc, char **argv) 79{ 80 time_t atime; 81 uid_t myuid; 82 int msgsok, myttyfd; 83 char tty[MAXPATHLEN], *mytty; 84 85 (void)setlocale(LC_CTYPE, ""); 86 87 while (getopt(argc, argv, "") != -1) 88 usage(); 89 argc -= optind; 90 argv += optind; 91 92 /* check that sender has write enabled */ 93 if (isatty(fileno(stdin))) 94 myttyfd = fileno(stdin); 95 else if (isatty(fileno(stdout))) 96 myttyfd = fileno(stdout); 97 else if (isatty(fileno(stderr))) 98 myttyfd = fileno(stderr); 99 else 100 errx(1, "can't find your tty"); 101 if (!(mytty = ttyname(myttyfd))) 102 errx(1, "can't find your tty's name"); 103 if (!strncmp(mytty, _PATH_DEV, strlen(_PATH_DEV))) 104 mytty += strlen(_PATH_DEV); 105 if (term_chk(mytty, &msgsok, &atime, 1)) 106 exit(1); 107 if (!msgsok) 108 errx(1, "you have write permission turned off"); 109 110 myuid = getuid(); 111 112 /* check args */ 113 switch (argc) { 114 case 1: 115 search_utmp(argv[0], tty, mytty, myuid); 116 do_write(tty, mytty, myuid); 117 break; 118 case 2: 119 if (!strncmp(argv[1], _PATH_DEV, strlen(_PATH_DEV))) 120 argv[1] += strlen(_PATH_DEV); 121 if (utmp_chk(argv[0], argv[1])) 122 errx(1, "%s is not logged in on %s", argv[0], argv[1]); 123 if (term_chk(argv[1], &msgsok, &atime, 1)) 124 exit(1); 125 if (myuid && !msgsok) 126 errx(1, "%s has messages disabled on %s", argv[0], argv[1]); 127 do_write(argv[1], mytty, myuid); 128 break; 129 default: 130 usage(); 131 } 132 done(0); 133 return (0); 134} 135 136static void 137usage(void) 138{ 139 (void)fprintf(stderr, "usage: write user [tty]\n"); 140 exit(1); 141} 142 143/* 144 * utmp_chk - checks that the given user is actually logged in on 145 * the given tty 146 */ 147int 148utmp_chk(char *user, char *tty) 149{
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149 struct utmp u; 150 int ufd;
| 150 struct utmpx lu, *u;
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151
| 151
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152 if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0) 153 return(0); /* ignore error, shouldn't happen anyway */ 154 155 while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u)) 156 if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0 && 157 strncmp(tty, u.ut_line, sizeof(u.ut_line)) == 0) { 158 (void)close(ufd);
| 152 strncpy(lu.ut_line, tty, sizeof lu.ut_line); 153 setutxent(); 154 while ((u = getutxline(&lu)) != NULL) 155 if (u->ut_type == USER_PROCESS && 156 strcmp(user, u->ut_user) == 0) { 157 endutxent();
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159 return(0); 160 }
| 158 return(0); 159 }
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161 162 (void)close(ufd);
| 160 endutxent();
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163 return(1); 164} 165 166/* 167 * search_utmp - search utmp for the "best" terminal to write to 168 * 169 * Ignores terminals with messages disabled, and of the rest, returns 170 * the one with the most recent access time. Returns as value the number 171 * of the user's terminals with messages enabled, or -1 if the user is 172 * not logged in at all. 173 * 174 * Special case for writing to yourself - ignore the terminal you're 175 * writing from, unless that's the only terminal with messages enabled. 176 */ 177void 178search_utmp(char *user, char *tty, char *mytty, uid_t myuid) 179{
| 161 return(1); 162} 163 164/* 165 * search_utmp - search utmp for the "best" terminal to write to 166 * 167 * Ignores terminals with messages disabled, and of the rest, returns 168 * the one with the most recent access time. Returns as value the number 169 * of the user's terminals with messages enabled, or -1 if the user is 170 * not logged in at all. 171 * 172 * Special case for writing to yourself - ignore the terminal you're 173 * writing from, unless that's the only terminal with messages enabled. 174 */ 175void 176search_utmp(char *user, char *tty, char *mytty, uid_t myuid) 177{
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180 struct utmp u;
| 178 struct utmpx *u;
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181 time_t bestatime, atime;
| 179 time_t bestatime, atime;
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182 int ufd, nloggedttys, nttys, msgsok, user_is_me; 183 char atty[UT_LINESIZE + 1];
| 180 int nloggedttys, nttys, msgsok, user_is_me;
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184
| 181
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185 if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0) 186 err(1, "utmp"); 187
| |
188 nloggedttys = nttys = 0; 189 bestatime = 0; 190 user_is_me = 0;
| 182 nloggedttys = nttys = 0; 183 bestatime = 0; 184 user_is_me = 0;
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191 while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u)) 192 if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0) {
| 185 186 setutxent(); 187 while ((u = getutxent()) != NULL) 188 if (u->ut_type == USER_PROCESS && 189 strcmp(user, u->ut_user) == 0) {
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193 ++nloggedttys;
| 190 ++nloggedttys;
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194 (void)strncpy(atty, u.ut_line, UT_LINESIZE); 195 atty[UT_LINESIZE] = '\0'; 196 if (term_chk(atty, &msgsok, &atime, 0))
| 191 if (term_chk(u->ut_line, &msgsok, &atime, 0))
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197 continue; /* bad term? skip */ 198 if (myuid && !msgsok) 199 continue; /* skip ttys with msgs off */
| 192 continue; /* bad term? skip */ 193 if (myuid && !msgsok) 194 continue; /* skip ttys with msgs off */
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200 if (strcmp(atty, mytty) == 0) {
| 195 if (strcmp(u->ut_line, mytty) == 0) {
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201 user_is_me = 1; 202 continue; /* don't write to yourself */ 203 } 204 ++nttys; 205 if (atime > bestatime) { 206 bestatime = atime;
| 196 user_is_me = 1; 197 continue; /* don't write to yourself */ 198 } 199 ++nttys; 200 if (atime > bestatime) { 201 bestatime = atime;
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207 (void)strcpy(tty, atty);
| 202 (void)strlcpy(tty, u->ut_line, MAXPATHLEN);
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208 } 209 }
| 203 } 204 }
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| 205 endutxent();
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210
| 206
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211 (void)close(ufd);
| |
212 if (nloggedttys == 0) 213 errx(1, "%s is not logged in", user); 214 if (nttys == 0) { 215 if (user_is_me) { /* ok, so write to yourself! */
| 207 if (nloggedttys == 0) 208 errx(1, "%s is not logged in", user); 209 if (nttys == 0) { 210 if (user_is_me) { /* ok, so write to yourself! */
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216 (void)strcpy(tty, mytty);
| 211 (void)strlcpy(tty, mytty, MAXPATHLEN);
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217 return; 218 } 219 errx(1, "%s has messages disabled", user); 220 } else if (nttys > 1) { 221 warnx("%s is logged in more than once; writing to %s", user, tty); 222 } 223} 224 225/* 226 * term_chk - check that a terminal exists, and get the message bit 227 * and the access time 228 */ 229int 230term_chk(char *tty, int *msgsokP, time_t *atimeP, int showerror) 231{ 232 struct stat s; 233 char path[MAXPATHLEN]; 234 235 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty); 236 if (stat(path, &s) < 0) { 237 if (showerror) 238 warn("%s", path); 239 return(1); 240 } 241 *msgsokP = (s.st_mode & (S_IWRITE >> 3)) != 0; /* group write bit */ 242 *atimeP = s.st_atime; 243 return(0); 244} 245 246/* 247 * do_write - actually make the connection 248 */ 249void 250do_write(char *tty, char *mytty, uid_t myuid) 251{ 252 const char *login; 253 char *nows; 254 struct passwd *pwd; 255 time_t now; 256 char path[MAXPATHLEN], host[MAXHOSTNAMELEN], line[512]; 257 258 /* Determine our login name before we reopen() stdout */ 259 if ((login = getlogin()) == NULL) { 260 if ((pwd = getpwuid(myuid))) 261 login = pwd->pw_name; 262 else 263 login = "???"; 264 } 265 266 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty); 267 if ((freopen(path, "w", stdout)) == NULL) 268 err(1, "%s", path); 269 270 (void)signal(SIGINT, done); 271 (void)signal(SIGHUP, done); 272 273 /* print greeting */ 274 if (gethostname(host, sizeof(host)) < 0) 275 (void)strcpy(host, "???"); 276 now = time((time_t *)NULL); 277 nows = ctime(&now); 278 nows[16] = '\0'; 279 (void)printf("\r\n\007\007\007Message from %s@%s on %s at %s ...\r\n", 280 login, host, mytty, nows + 11); 281 282 while (fgets(line, sizeof(line), stdin) != NULL) 283 wr_fputs(line); 284} 285 286/* 287 * done - cleanup and exit 288 */ 289void 290done(int n __unused) 291{ 292 (void)printf("EOF\r\n"); 293 exit(0); 294} 295 296/* 297 * wr_fputs - like fputs(), but makes control characters visible and 298 * turns \n into \r\n 299 */ 300void 301wr_fputs(unsigned char *s) 302{ 303 304#define PUTC(c) if (putchar(c) == EOF) err(1, NULL); 305 306 for (; *s != '\0'; ++s) { 307 if (*s == '\n') { 308 PUTC('\r'); 309 } else if (((*s & 0x80) && *s < 0xA0) || 310 /* disable upper controls */ 311 (!isprint(*s) && !isspace(*s) && 312 *s != '\a' && *s != '\b') 313 ) { 314 if (*s & 0x80) { 315 *s &= ~0x80; 316 PUTC('M'); 317 PUTC('-'); 318 } 319 if (iscntrl(*s)) { 320 *s ^= 0x40; 321 PUTC('^'); 322 } 323 } 324 PUTC(*s); 325 } 326 return; 327#undef PUTC 328}
| 212 return; 213 } 214 errx(1, "%s has messages disabled", user); 215 } else if (nttys > 1) { 216 warnx("%s is logged in more than once; writing to %s", user, tty); 217 } 218} 219 220/* 221 * term_chk - check that a terminal exists, and get the message bit 222 * and the access time 223 */ 224int 225term_chk(char *tty, int *msgsokP, time_t *atimeP, int showerror) 226{ 227 struct stat s; 228 char path[MAXPATHLEN]; 229 230 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty); 231 if (stat(path, &s) < 0) { 232 if (showerror) 233 warn("%s", path); 234 return(1); 235 } 236 *msgsokP = (s.st_mode & (S_IWRITE >> 3)) != 0; /* group write bit */ 237 *atimeP = s.st_atime; 238 return(0); 239} 240 241/* 242 * do_write - actually make the connection 243 */ 244void 245do_write(char *tty, char *mytty, uid_t myuid) 246{ 247 const char *login; 248 char *nows; 249 struct passwd *pwd; 250 time_t now; 251 char path[MAXPATHLEN], host[MAXHOSTNAMELEN], line[512]; 252 253 /* Determine our login name before we reopen() stdout */ 254 if ((login = getlogin()) == NULL) { 255 if ((pwd = getpwuid(myuid))) 256 login = pwd->pw_name; 257 else 258 login = "???"; 259 } 260 261 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty); 262 if ((freopen(path, "w", stdout)) == NULL) 263 err(1, "%s", path); 264 265 (void)signal(SIGINT, done); 266 (void)signal(SIGHUP, done); 267 268 /* print greeting */ 269 if (gethostname(host, sizeof(host)) < 0) 270 (void)strcpy(host, "???"); 271 now = time((time_t *)NULL); 272 nows = ctime(&now); 273 nows[16] = '\0'; 274 (void)printf("\r\n\007\007\007Message from %s@%s on %s at %s ...\r\n", 275 login, host, mytty, nows + 11); 276 277 while (fgets(line, sizeof(line), stdin) != NULL) 278 wr_fputs(line); 279} 280 281/* 282 * done - cleanup and exit 283 */ 284void 285done(int n __unused) 286{ 287 (void)printf("EOF\r\n"); 288 exit(0); 289} 290 291/* 292 * wr_fputs - like fputs(), but makes control characters visible and 293 * turns \n into \r\n 294 */ 295void 296wr_fputs(unsigned char *s) 297{ 298 299#define PUTC(c) if (putchar(c) == EOF) err(1, NULL); 300 301 for (; *s != '\0'; ++s) { 302 if (*s == '\n') { 303 PUTC('\r'); 304 } else if (((*s & 0x80) && *s < 0xA0) || 305 /* disable upper controls */ 306 (!isprint(*s) && !isspace(*s) && 307 *s != '\a' && *s != '\b') 308 ) { 309 if (*s & 0x80) { 310 *s &= ~0x80; 311 PUTC('M'); 312 PUTC('-'); 313 } 314 if (iscntrl(*s)) { 315 *s ^= 0x40; 316 PUTC('^'); 317 } 318 } 319 PUTC(*s); 320 } 321 return; 322#undef PUTC 323}
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