usr.bin/msgs/msgs.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1980, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 /*
  33  * msgs - a user bulletin board program
  34  *
  35  * usage:
  36  *      msgs [fhlopq] [[-]number]       to read messages
  37  *      msgs -s                         to place messages
  38  *      msgs -c [-days]                 to clean up the bulletin board
  39  *
  40  * prompt commands are:
  41  *      y       print message
  42  *      n       flush message, go to next message
  43  *      q       flush message, quit
  44  *      p       print message, turn on 'pipe thru more' mode
  45  *      P       print message, turn off 'pipe thru more' mode
  46  *      -       reprint last message
  47  *      s[-][<num>] [<filename>]        save message
  48  *      m[-][<num>]     mail with message in temp mbox
  49  *      x       exit without flushing this message
  50  *      <num>   print message number <num>
  51  */
  52
  53 #define V7              /* will look for TERM in the environment */
  54 #define OBJECT          /* will object to messages without Subjects */
  55 /* #define REJECT */    /* will reject messages without Subjects
  56                            (OBJECT must be defined also) */
  57 /* #define UNBUFFERED *//* use unbuffered output */
  58
  59 #include <sys/param.h>
  60 #include <sys/stat.h>
  61 #include <ctype.h>
  62 #include <dirent.h>
  63 #include <err.h>
  64 #include <errno.h>
  65 #include <fcntl.h>
  66 #include <locale.h>
  67 #include <pwd.h>
  68 #include <setjmp.h>
  69 #include <termcap.h>
  70 #include <termios.h>
  71 #include <signal.h>
  72 #include <stdio.h>
  73 #include <stdlib.h>
  74 #include <string.h>
  75 #include <time.h>
  76 #include <unistd.h>
  77 #include <stdbool.h>
  78 #include "pathnames.h"
  79
  80 #define CMODE   0644            /* bounds file creation mode */
  81 #define SUPERUSER       0       /* superuser uid */
  82 #define DAEMON          1       /* daemon uid */
  83 #define NLINES  24              /* default number of lines/crt screen */
  84 #define NDAYS   21              /* default keep time for messages */
  85 #define DAYS    *24*60*60       /* seconds/day */
  86 #define MSGSRC  ".msgsrc"       /* user's rc file */
  87 #define BOUNDS  "bounds"        /* message bounds file */
  88 #define NEXT    "Next message? [yq]"
  89 #define MORE    "More? [ynq]"
  90 #define NOMORE  "(No more) [q] ?"
  91
  92 static FILE     *msgsrc;
  93 static FILE     *newmsg;
  94 static const char *sep = "-";
  95 static char     inbuf[BUFSIZ];
  96 static char     fname[MAXPATHLEN];
  97 static char     cmdbuf[MAXPATHLEN + MAXPATHLEN];
  98 static char     subj[128];
  99 static char     from[128];
 100 static char     date[128];
 101 static char     *ptr;
 102 static char     *in;
 103 static bool     local;
 104 static bool     ruptible;
 105 static bool     totty;
 106 static bool     seenfrom;
 107 static bool     seensubj;
 108 static bool     blankline;
 109 static bool     printing = false;
 110 static bool     mailing = false;
 111 static bool     quitit = false;
 112 static bool     sending = false;
 113 static bool     intrpflg = false;
 114 static uid_t    uid;
 115 static int      msg;
 116 static int      prevmsg;
 117 static int      lct;
 118 static int      nlines;
 119 static int      Lpp = 0;
 120 static time_t   t;
 121 static time_t   keep;
 122
 123 /* option initialization */
 124 static bool     hdrs = false;
 125 static bool     qopt = false;
 126 static bool     hush = false;
 127 static bool     send_msg = false;
 128 static bool     locomode = false;
 129 static bool     use_pager = false;
 130 static bool     clean = false;
 131 static bool     lastcmd = false;
 132 static jmp_buf  tstpbuf;
 133
 134 static void     ask(const char *);
 135 static void     gfrsub(FILE *);
 136 static int      linecnt(FILE *);
 137 static int      next(char *);
 138 static char     *nxtfld(char *);
 139 static void     onsusp(int);
 140 static void     onintr(int);
 141 static void     prmesg(int);
 142 static void     usage(void);
 143
 144 int
 145 main(int argc, char *argv[])
 146 {
 147         bool newrc, already;
 148         int rcfirst = 0;                /* first message to print (from .rc) */
 149         int rcback = 0;                 /* amount to back off of rcfirst */
 150         int firstmsg = 0, nextmsg = 0, lastmsg = 0;
 151         int blast = 0;
 152         struct stat buf;                /* stat to check access of bounds */
 153         FILE *bounds;
 154         char *cp;
 155
 156 #ifdef UNBUFFERED
 157         setbuf(stdout, NULL);
 158 #endif
 159         setlocale(LC_ALL, "");
 160
 161         time(&t);
 162         if (setuid(uid = getuid()) != 0)
 163                 err(1, "setuid failed");
 164         ruptible = (signal(SIGINT, SIG_IGN) == SIG_DFL);
 165         if (ruptible)
 166                 signal(SIGINT, SIG_DFL);
 167
 168         argc--, argv++;
 169         while (argc > 0) {
 170                 if (isdigit(argv[0][0])) {      /* starting message # */
 171                         rcfirst = atoi(argv[0]);
 172                 }
 173                 else if (isdigit(argv[0][1])) { /* backward offset */
 174                         rcback = atoi( &( argv[0][1] ) );
 175                 }
 176                 else {
 177                         ptr = *argv;
 178                         while (*ptr) switch (*ptr++) {
 179
 180                         case '-':
 181                                 break;
 182
 183                         case 'c':
 184                                 if (uid != SUPERUSER && uid != DAEMON)
 185                                         errx(1,
 186                                 "only the super-user can use the c flag");
 187                                 clean = true;
 188                                 break;
 189
 190                         case 'f':               /* silently */
 191                                 hush = true;
 192                                 break;
 193
 194                         case 'h':               /* headers only */
 195                                 hdrs = true;
 196                                 break;
 197
 198                         case 'l':               /* local msgs only */
 199                                 locomode = true;
 200                                 break;
 201
 202                         case 'o':               /* option to save last message */
 203                                 lastcmd = true;
 204                                 break;
 205
 206                         case 'p':               /* pipe thru 'more' during long msgs */
 207                                 use_pager = true;
 208                                 break;
 209
 210                         case 'q':               /* query only */
 211                                 qopt = true;
 212                                 break;
 213
 214                         case 's':               /* sending TO msgs */
 215                                 send_msg = true;
 216                                 break;
 217
 218                         default:
 219                                 usage();
 220                         }
 221                 }
 222                 argc--, argv++;
 223         }
 224
 225         /*
 226          * determine current message bounds
 227          */
 228         snprintf(fname, sizeof(fname), "%s/%s", _PATH_MSGS, BOUNDS);
 229
 230         /*
 231          * Test access rights to the bounds file
 232          * This can be a little tricky.  if(send_msg), then
 233          * we will create it.  We assume that if(send_msg),
 234          * then you have write permission there.
 235          * Else, it better be there, or we bail.
 236          */
 237         if (!send_msg) {
 238                 if (stat(fname, &buf) < 0) {
 239                         if (!hush) {
 240                                 err(errno, "%s", fname);
 241                         } else {
 242                                 exit(1);
 243                         }
 244                 }
 245         }
 246         bounds = fopen(fname, "r");
 247
 248         if (bounds != NULL) {
 249                 fscanf(bounds, "%d %d\n", &firstmsg, &lastmsg);
 250                 fclose(bounds);
 251                 blast = lastmsg;        /* save upper bound */
 252         }
 253
 254         if (clean)
 255                 keep = t - (rcback? rcback : NDAYS) DAYS;
 256
 257         if (clean || bounds == NULL) {  /* relocate message bounds */
 258                 struct dirent *dp;
 259                 struct stat stbuf;
 260                 bool seenany = false;
 261                 DIR     *dirp;
 262
 263                 dirp = opendir(_PATH_MSGS);
 264                 if (dirp == NULL)
 265                         err(errno, "%s", _PATH_MSGS);
 266
 267                 firstmsg = 32767;
 268                 lastmsg = 0;
 269
 270                 for (dp = readdir(dirp); dp != NULL; dp = readdir(dirp)){
 271                         cp = dp->d_name;
 272                         int i = 0;
 273
 274                         if (dp->d_ino == 0)
 275                                 continue;
 276                         if (dp->d_namlen == 0)
 277                                 continue;
 278
 279                         if (clean)
 280                                 snprintf(inbuf, sizeof(inbuf), "%s/%s", _PATH_MSGS, cp);
 281
 282                         while (isdigit(*cp))
 283                                 i = i * 10 + *cp++ - '0';
 284                         if (*cp)
 285                                 continue;       /* not a message! */
 286
 287                         if (clean) {
 288                                 if (stat(inbuf, &stbuf) != 0)
 289                                         continue;
 290                                 if (stbuf.st_mtime < keep
 291                                     && stbuf.st_mode&S_IWRITE) {
 292                                         unlink(inbuf);
 293                                         continue;
 294                                 }
 295                         }
 296
 297                         if (i > lastmsg)
 298                                 lastmsg = i;
 299                         if (i < firstmsg)
 300                                 firstmsg = i;
 301                         seenany = true;
 302                 }
 303                 closedir(dirp);
 304
 305                 if (!seenany) {
 306                         if (blast != 0) /* never lower the upper bound! */
 307                                 lastmsg = blast;
 308                         firstmsg = lastmsg + 1;
 309                 }
 310                 else if (blast > lastmsg)
 311                         lastmsg = blast;
 312
 313                 if (!send_msg) {
 314                         bounds = fopen(fname, "w");
 315                         if (bounds == NULL)
 316                                 err(errno, "%s", fname);
 317                         chmod(fname, CMODE);
 318                         fprintf(bounds, "%d %d\n", firstmsg, lastmsg);
 319                         fclose(bounds);
 320                 }
 321         }
 322
 323         if (send_msg) {
 324                 /*
 325                  * Send mode - place msgs in _PATH_MSGS
 326                  */
 327                 bounds = fopen(fname, "w");
 328                 if (bounds == NULL)
 329                         err(errno, "%s", fname);
 330
 331                 nextmsg = lastmsg + 1;
 332                 snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, nextmsg);
 333                 newmsg = fopen(fname, "w");
 334                 if (newmsg == NULL)
 335                         err(errno, "%s", fname);
 336                 chmod(fname, CMODE);
 337
 338                 fprintf(bounds, "%d %d\n", firstmsg, nextmsg);
 339                 fclose(bounds);
 340
 341                 sending = true;
 342                 if (ruptible)
 343                         signal(SIGINT, onintr);
 344
 345                 if (isatty(fileno(stdin))) {
 346                         ptr = getpwuid(uid)->pw_name;
 347                         printf("Message %d:\nFrom %s %sSubject: ",
 348                                 nextmsg, ptr, ctime(&t));
 349                         fflush(stdout);
 350                         fgets(inbuf, sizeof inbuf, stdin);
 351                         putchar('\n');
 352                         fflush(stdout);
 353                         fprintf(newmsg, "From %s %sSubject: %s\n",
 354                                 ptr, ctime(&t), inbuf);
 355                         blankline = seensubj = true;
 356                 }
 357                 else
 358                         blankline = seensubj = false;
 359                 for (;;) {
 360                         fgets(inbuf, sizeof inbuf, stdin);
 361                         if (feof(stdin) || ferror(stdin))
 362                                 break;
 363                         blankline = (blankline || (inbuf[0] == '\n'));
 364                         seensubj = (seensubj || (!blankline && (strncmp(inbuf, "Subj", 4) == 0)));
 365                         fputs(inbuf, newmsg);
 366                 }
 367 #ifdef OBJECT
 368                 if (!seensubj) {
 369                         printf("NOTICE: Messages should have a Subject field!\n");
 370 #ifdef REJECT
 371                         unlink(fname);
 372 #endif
 373                         exit(1);
 374                 }
 375 #endif
 376                 exit(ferror(stdin));
 377         }
 378         if (clean)
 379                 exit(0);
 380
 381         /*
 382          * prepare to display messages
 383          */
 384         totty = (isatty(fileno(stdout)) != 0);
 385         use_pager = use_pager && totty;
 386
 387         if ((cp = getenv("HOME")) == NULL || *cp == '\0') {
 388                 fprintf(stderr, "Error, no home directory!\n");
 389                 exit(1);
 390         }
 391         snprintf(fname, sizeof(fname), "%s/%s", cp, MSGSRC);
 392         msgsrc = fopen(fname, "r");
 393         if (msgsrc) {
 394                 newrc = false;
 395                 fscanf(msgsrc, "%d\n", &nextmsg);
 396                 fclose(msgsrc);
 397                 if (nextmsg > lastmsg+1) {
 398                         printf("Warning: bounds have been reset (%d, %d)\n",
 399                                 firstmsg, lastmsg);
 400                         truncate(fname, (off_t)0);
 401                         newrc = true;
 402                 }
 403                 else if (!rcfirst)
 404                         rcfirst = nextmsg - rcback;
 405         }
 406         else
 407                 newrc = true;
 408         msgsrc = fopen(fname, "r+");
 409         if (msgsrc == NULL)
 410                 msgsrc = fopen(fname, "w");
 411         if (msgsrc == NULL)
 412                 err(errno, "%s", fname);
 413         if (rcfirst) {
 414                 if (rcfirst > lastmsg+1) {
 415                         printf("Warning: the last message is number %d.\n",
 416                                 lastmsg);
 417                         rcfirst = nextmsg;
 418                 }
 419                 if (rcfirst > firstmsg)
 420                         firstmsg = rcfirst;     /* don't set below first msg */
 421         }
 422         if (newrc) {
 423                 nextmsg = firstmsg;
 424                 rewind(msgsrc);
 425                 fprintf(msgsrc, "%d\n", nextmsg);
 426                 fflush(msgsrc);
 427         }
 428
 429 #ifdef V7
 430         if (totty) {
 431                 struct winsize win;
 432                 if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1)
 433                         Lpp = win.ws_row;
 434                 if (Lpp <= 0) {
 435                         if (tgetent(inbuf, getenv("TERM")) <= 0
 436                             || (Lpp = tgetnum("li")) <= 0) {
 437                                 Lpp = NLINES;
 438                         }
 439                 }
 440         }
 441 #endif
 442         Lpp -= 6;       /* for headers, etc. */
 443
 444         already = false;
 445         prevmsg = firstmsg;
 446         printing = true;
 447         if (ruptible)
 448                 signal(SIGINT, onintr);
 449
 450         /*
 451          * Main program loop
 452          */
 453         for (msg = firstmsg; msg <= lastmsg; msg++) {
 454
 455                 snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, msg);
 456                 newmsg = fopen(fname, "r");
 457                 if (newmsg == NULL)
 458                         continue;
 459
 460                 gfrsub(newmsg);         /* get From and Subject fields */
 461                 if (locomode && !local) {
 462                         fclose(newmsg);
 463                         continue;
 464                 }
 465
 466                 if (qopt) {     /* This has to be located here */
 467                         printf("There are new messages.\n");
 468                         exit(0);
 469                 }
 470
 471                 if (already && !hdrs)
 472                         putchar('\n');
 473
 474                 /*
 475                  * Print header
 476                  */
 477                 if (totty)
 478                         signal(SIGTSTP, onsusp);
 479                 (void) setjmp(tstpbuf);
 480                 already = true;
 481                 nlines = 2;
 482                 if (seenfrom) {
 483                         printf("Message %d:\nFrom %s %s", msg, from, date);
 484                         nlines++;
 485                 }
 486                 if (seensubj) {
 487                         printf("Subject: %s", subj);
 488                         nlines++;
 489                 }
 490                 else {
 491                         if (seenfrom) {
 492                                 putchar('\n');
 493                                 nlines++;
 494                         }
 495                         while (nlines < 6
 496                             && fgets(inbuf, sizeof inbuf, newmsg)
 497                             && inbuf[0] != '\n') {
 498                                 fputs(inbuf, stdout);
 499                                 nlines++;
 500                         }
 501                 }
 502
 503                 lct = linecnt(newmsg);
 504                 if (lct)
 505                         printf("(%d%sline%s) ", lct, seensubj? " " : " more ",
 506                             (lct == 1) ? "" : "s");
 507
 508                 if (hdrs) {
 509                         printf("\n-----\n");
 510                         fclose(newmsg);
 511                         continue;
 512                 }
 513
 514                 /*
 515                  * Ask user for command
 516                  */
 517                 if (totty)
 518                         ask(lct? MORE : (msg==lastmsg? NOMORE : NEXT));
 519                 else
 520                         inbuf[0] = 'y';
 521                 if (totty)
 522                         signal(SIGTSTP, SIG_DFL);
 523 cmnd:
 524                 in = inbuf;
 525                 switch (*in) {
 526                         case 'x':
 527                                 /* FALLTHROUGH */
 528                         case 'X':
 529                                 exit(0);
 530                                 /* NOTREACHED */
 531
 532                         case 'q':
 533                                 /* FALLTHROUGH */
 534                         case 'Q':
 535                                 quitit = true;
 536                                 printf("--Postponed--\n");
 537                                 exit(0);
 538                                 /* NOTREACHED */
 539
 540                         case 'n':
 541                                 /* FALLTHROUGH */
 542                         case 'N':
 543                                 if (msg >= nextmsg) sep = "Flushed";
 544                                 prevmsg = msg;
 545                                 break;
 546
 547                         case 'p':
 548                                 /* FALLTHROUGH */
 549                         case 'P':
 550                                 use_pager = (*in++ == 'p');
 551                                 /* FALLTHROUGH */
 552                         case '\n':
 553                                 /* FALLTHROUGH */
 554                         case 'y':
 555                         default:
 556                                 if (*in == '-') {
 557                                         msg = prevmsg-1;
 558                                         sep = "replay";
 559                                         break;
 560                                 }
 561                                 if (isdigit(*in)) {
 562                                         msg = next(in);
 563                                         sep = in;
 564                                         break;
 565                                 }
 566
 567                                 prmesg(nlines + lct + (seensubj? 1 : 0));
 568                                 prevmsg = msg;
 569
 570                 }
 571
 572                 printf("--%s--\n", sep);
 573                 sep = "-";
 574                 if (msg >= nextmsg) {
 575                         nextmsg = msg + 1;
 576                         rewind(msgsrc);
 577                         fprintf(msgsrc, "%d\n", nextmsg);
 578                         fflush(msgsrc);
 579                 }
 580                 if (newmsg)
 581                         fclose(newmsg);
 582                 if (quitit)
 583                         break;
 584         }
 585
 586         /*
 587          * Make sure .rc file gets updated
 588          */
 589         if (--msg >= nextmsg) {
 590                 nextmsg = msg + 1;
 591                 rewind(msgsrc);
 592                 fprintf(msgsrc, "%d\n", nextmsg);
 593                 fflush(msgsrc);
 594         }
 595         if (already && !quitit && lastcmd && totty) {
 596                 /*
 597                  * save or reply to last message?
 598                  */
 599                 msg = prevmsg;
 600                 ask(NOMORE);
 601                 if (inbuf[0] == '-' || isdigit(inbuf[0]))
 602                         goto cmnd;
 603         }
 604         if (!(already || hush || qopt))
 605                 printf("No new messages.\n");
 606         exit(0);
 607         /* NOTREACHED */
 608 }
 609
 610 static void
 611 usage(void)
 612 {
 613         fprintf(stderr, "usage: msgs [fhlopq] [[-]number]\n");
 614         exit(1);
 615 }
 616
 617 static void
 618 prmesg(int length)
 619 {
 620         FILE *outf;
 621         char *env_pager;
 622
 623         if (use_pager && length > Lpp) {
 624                 signal(SIGPIPE, SIG_IGN);
 625                 signal(SIGQUIT, SIG_IGN);
 626                 if ((env_pager = getenv("PAGER")) == NULL) {
 627                         snprintf(cmdbuf, sizeof(cmdbuf), _PATH_PAGER, Lpp);
 628                 } else {
 629                         snprintf(cmdbuf, sizeof(cmdbuf), "%s", env_pager);
 630                 }
 631                 outf = popen(cmdbuf, "w");
 632                 if (!outf)
 633                         outf = stdout;
 634                 else
 635                         setbuf(outf, (char *)NULL);
 636         }
 637         else
 638                 outf = stdout;
 639
 640         if (seensubj)
 641                 putc('\n', outf);
 642
 643         while (fgets(inbuf, sizeof inbuf, newmsg)) {
 644                 fputs(inbuf, outf);
 645                 if (ferror(outf)) {
 646                         clearerr(outf);
 647                         break;
 648                 }
 649         }
 650
 651         if (outf != stdout) {
 652                 pclose(outf);
 653                 signal(SIGPIPE, SIG_DFL);
 654                 signal(SIGQUIT, SIG_DFL);
 655         }
 656         else {
 657                 fflush(stdout);
 658         }
 659
 660         /* force wait on output */
 661         tcdrain(fileno(stdout));
 662 }
 663
 664 static void
 665 onintr(int unused __unused)
 666 {
 667         signal(SIGINT, onintr);
 668         if (mailing)
 669                 unlink(fname);
 670         if (sending) {
 671                 unlink(fname);
 672                 puts("--Killed--");
 673                 exit(1);
 674         }
 675         if (printing) {
 676                 putchar('\n');
 677                 if (hdrs)
 678                         exit(0);
 679                 sep = "Interrupt";
 680                 if (newmsg)
 681                         fseeko(newmsg, (off_t)0, SEEK_END);
 682                 intrpflg = true;
 683         }
 684 }
 685
 686 /*
 687  * We have just gotten a susp.  Suspend and prepare to resume.
 688  */
 689 static void
 690 onsusp(int unused __unused)
 691 {
 692         signal(SIGTSTP, SIG_DFL);
 693         sigsetmask(0);
 694         kill(0, SIGTSTP);
 695         signal(SIGTSTP, onsusp);
 696         if (!mailing)
 697                 longjmp(tstpbuf, 0);
 698 }
 699
 700 static int
 701 linecnt(FILE *f)
 702 {
 703         off_t oldpos = ftello(f);
 704         int l = 0;
 705         char lbuf[BUFSIZ];
 706
 707         while (fgets(lbuf, sizeof lbuf, f))
 708                 l++;
 709         clearerr(f);
 710         fseeko(f, oldpos, SEEK_SET);
 711         return (l);
 712 }
 713
 714 static int
 715 next(char *buf)
 716 {
 717         int i;
 718         sscanf(buf, "%d", &i);
 719         sprintf(buf, "Goto %d", i);
 720         return(--i);
 721 }
 722
 723 static void
 724 ask(const char *prompt)
 725 {
 726         char    inch;
 727         int     n, cmsg, fd;
 728         off_t   oldpos;
 729         FILE    *cpfrom, *cpto;
 730
 731         printf("%s ", prompt);
 732         fflush(stdout);
 733         intrpflg = false;
 734         (void) fgets(inbuf, sizeof inbuf, stdin);
 735         if ((n = strlen(inbuf)) > 0 && inbuf[n - 1] == '\n')
 736                 inbuf[n - 1] = '\0';
 737         if (intrpflg)
 738                 inbuf[0] = 'x';
 739
 740         /*
 741          * Handle 'mail' and 'save' here.
 742          */
 743         if ((inch = inbuf[0]) == 's' || inch == 'm') {
 744                 if (inbuf[1] == '-')
 745                         cmsg = prevmsg;
 746                 else if (isdigit(inbuf[1]))
 747                         cmsg = atoi(&inbuf[1]);
 748                 else
 749                         cmsg = msg;
 750                 snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, cmsg);
 751
 752                 oldpos = ftello(newmsg);
 753
 754                 cpfrom = fopen(fname, "r");
 755                 if (!cpfrom) {
 756                         printf("Message %d not found\n", cmsg);
 757                         ask (prompt);
 758                         return;
 759                 }
 760
 761                 if (inch == 's') {
 762                         in = nxtfld(inbuf);
 763                         if (*in) {
 764                                 for (n=0; in[n] > ' '; n++) { /* sizeof fname? */
 765                                         fname[n] = in[n];
 766                                 }
 767                                 fname[n] = '\0';
 768                         }
 769                         else
 770                                 strcpy(fname, "Messages");
 771                         fd = open(fname, O_RDWR|O_EXCL|O_CREAT|O_APPEND);
 772                 }
 773                 else {
 774                         strcpy(fname, _PATH_TMP);
 775                         fd = mkstemp(fname);
 776                         if (fd != -1) {
 777                                 snprintf(cmdbuf, sizeof(cmdbuf), _PATH_MAIL,
 778                                     fname);
 779                                 mailing = true;
 780                         }
 781                 }
 782                 if (fd == -1 || (cpto = fdopen(fd, "a")) == NULL) {
 783                         if (fd != -1)
 784                                 close(fd);
 785                         warn("%s", fname);
 786                         mailing = false;
 787                         fseeko(newmsg, oldpos, SEEK_SET);
 788                         ask(prompt);
 789                         fclose(cpfrom);
 790                         return;
 791                 }
 792
 793                 while ((n = fread(inbuf, 1, sizeof inbuf, cpfrom)))
 794                         fwrite(inbuf, 1, n, cpto);
 795
 796                 fclose(cpfrom);
 797                 fclose(cpto);
 798                 fseeko(newmsg, oldpos, SEEK_SET);/* reposition current message */
 799                 if (inch == 's')
 800                         printf("Message %d saved in \"%s\"\n", cmsg, fname);
 801                 else {
 802                         system(cmdbuf);
 803                         unlink(fname);
 804                         mailing = false;
 805                 }
 806                 ask(prompt);
 807         }
 808 }
 809
 810 static void
 811 gfrsub(FILE *infile)
 812 {
 813         off_t frompos;
 814         int count;
 815
 816         seensubj = seenfrom = false;
 817         local = true;
 818         subj[0] = from[0] = date[0] = '\0';
 819
 820         /*
 821          * Is this a normal message?
 822          */
 823         if (fgets(inbuf, sizeof inbuf, infile)) {
 824                 if (strncmp(inbuf, "From", 4)==0) {
 825                         /*
 826                          * expected form starts with From
 827                          */
 828                         seenfrom = true;
 829                         frompos = ftello(infile);
 830                         ptr = from;
 831                         in = nxtfld(inbuf);
 832                         if (*in) {
 833                                 count = sizeof(from) - 1;
 834                                 while (*in && *in > ' ' && count-- > 0) {
 835                                         if (*in == ':' || *in == '@' ||
 836                                             *in == '!')
 837                                                 local = false;
 838                                         *ptr++ = *in++;
 839                                 }
 840                         }
 841                         *ptr = '\0';
 842                         if (*(in = nxtfld(in)))
 843                                 strlcpy(date, in, sizeof date);
 844                         else {
 845                                 date[0] = '\n';
 846                                 date[1] = '\0';
 847                         }
 848                 }
 849                 else {
 850                         /*
 851                          * not the expected form
 852                          */
 853                         rewind(infile);
 854                         return;
 855                 }
 856         }
 857         else
 858                 /*
 859                  * empty file ?
 860                  */
 861                 return;
 862
 863         /*
 864          * look for Subject line until EOF or a blank line
 865          */
 866         while (fgets(inbuf, sizeof inbuf, infile)
 867             && !(blankline = (inbuf[0] == '\n'))) {
 868                 /*
 869                  * extract Subject line
 870                  */
 871                 if (!seensubj && strncmp(inbuf, "Subj", 4)==0) {
 872                         seensubj = true;
 873                         frompos = ftello(infile);
 874                         strlcpy(subj, nxtfld(inbuf), sizeof subj);
 875                 }
 876         }
 877         if (!blankline)
 878                 /*
 879                  * ran into EOF
 880                  */
 881                 fseeko(infile, frompos, SEEK_SET);
 882
 883         if (!seensubj)
 884                 /*
 885                  * for possible use with Mail
 886                  */
 887                 strlcpy(subj, "(No Subject)\n", sizeof subj);
 888 }
 889
 890 static char *
 891 nxtfld(char *s)
 892 {
 893         if (*s) while (*s && !isspace(*s)) s++;     /* skip over this field */
 894         if (*s) while (*s && isspace(*s)) s++;    /* find start of next field */
 895         return (s);
 896 }