diplodocus.org Git - nmh/blob - uip/mhshowsbr.c

   1
   2 /*
   3  * mhshowsbr.c -- routines to display the contents of MIME messages
   4  *
   5  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   6  * COPYRIGHT file in the root directory of the nmh distribution for
   7  * complete copyright information.
   8  */
   9
  10 #include <h/mh.h>
  11 #include <fcntl.h>
  12 #include <h/signals.h>
  13 #include <h/md5.h>
  14 #include <setjmp.h>
  15 #include <h/mts.h>
  16 #include <h/tws.h>
  17 #include <h/mime.h>
  18 #include <h/mhparse.h>
  19 #include <h/utils.h>
  20
  21 extern int debugsw;
  22
  23 int pausesw  = 1;
  24 int serialsw = 0;
  25 int nolist   = 0;
  26
  27 char *progsw = NULL;
  28
  29 /* flags for moreproc/header display */
  30 int nomore   = 0;
  31 char *formsw = NULL;
  32
  33 pid_t xpid = 0;
  34
  35 static sigjmp_buf intrenv;
  36
  37
  38 /* mhmisc.c */
  39 int part_ok (CT, int);
  40 int type_ok (CT, int);
  41 void content_error (char *, CT, char *, ...);
  42 void flush_errors (void);
  43
  44 /* mhlistsbr.c */
  45 int list_switch (CT, int, int, int, int);
  46 int list_content (CT, int, int, int, int);
  47
  48 /*
  49  * prototypes
  50  */
  51 void show_all_messages (CT *);
  52 int show_content_aux (CT, int, int, char *, char *);
  53
  54 /*
  55  * static prototypes
  56  */
  57 static void show_single_message (CT, char *);
  58 static void DisplayMsgHeader (CT, char *);
  59 static int show_switch (CT, int, int);
  60 static int show_content (CT, int, int);
  61 static int show_content_aux2 (CT, int, int, char *, char *, int, int, int, int, int);
  62 static int show_text (CT, int, int);
  63 static int show_multi (CT, int, int);
  64 static int show_multi_internal (CT, int, int);
  65 static int show_multi_aux (CT, int, int, char *);
  66 static int show_message_rfc822 (CT, int, int);
  67 static int show_partial (CT, int, int);
  68 static int show_external (CT, int, int);
  69 static void intrser (int);
  70
  71
  72 /*
  73  * Top level entry point to show/display a group of messages
  74  */
  75
  76 void
  77 show_all_messages (CT *cts)
  78 {
  79     CT ct, *ctp;
  80
  81     /*
  82      * If form is not specified, then get default form
  83      * for showing headers of MIME messages.
  84      */
  85     if (!formsw)
  86         formsw = getcpy (etcpath ("mhl.headers"));
  87
  88     /*
  89      * If form is "mhl.null", suppress display of header.
  90      */
  91     if (!strcmp (formsw, "mhl.null"))
  92         formsw = NULL;
  93
  94     for (ctp = cts; *ctp; ctp++) {
  95         ct = *ctp;
  96
  97         /* if top-level type is ok, then display message */
  98         if (type_ok (ct, 1))
  99             show_single_message (ct, formsw);
 100     }
 101 }
 102
 103
 104 /*
 105  * Entry point to show/display a single message
 106  */
 107
 108 static void
 109 show_single_message (CT ct, char *form)
 110 {
 111     sigset_t set, oset;
 112
 113     int status;
 114
 115     /* Allow user executable bit so that temporary directories created by
 116      * the viewer (e.g., lynx) are going to be accessible */
 117     umask (ct->c_umask & ~(0100));
 118
 119     /*
 120      * If you have a format file, then display
 121      * the message headers.
 122      */
 123     if (form)
 124         DisplayMsgHeader(ct, form);
 125     else
 126         xpid = 0;
 127
 128     /* Show the body of the message */
 129     show_switch (ct, 1, 0);
 130
 131     if (ct->c_fp) {
 132         fclose (ct->c_fp);
 133         ct->c_fp = NULL;
 134     }
 135     if (ct->c_ceclosefnx)
 136         (*ct->c_ceclosefnx) (ct);
 137
 138     /* block a few signals */
 139     sigemptyset (&set);
 140     sigaddset (&set, SIGHUP);
 141     sigaddset (&set, SIGINT);
 142     sigaddset (&set, SIGQUIT);
 143     sigaddset (&set, SIGTERM);
 144     sigprocmask (SIG_BLOCK, &set, &oset);
 145
 146     while (wait (&status) != NOTOK) {
 147         pidcheck (status);
 148         continue;
 149     }
 150
 151     /* reset the signal mask */
 152     sigprocmask (SIG_SETMASK, &oset, &set);
 153
 154     xpid = 0;
 155     flush_errors ();
 156 }
 157
 158
 159 /*
 160  * Use the mhlproc to show the header fields
 161  */
 162
 163 static void
 164 DisplayMsgHeader (CT ct, char *form)
 165 {
 166     pid_t child_id;
 167     int i, vecp;
 168     char **vec;
 169     char *file;
 170
 171     vec = argsplit(mhlproc, &file, &vecp);
 172     vec[vecp++] = getcpy("-form");
 173     vec[vecp++] = getcpy(form);
 174     vec[vecp++] = getcpy("-nobody");
 175     vec[vecp++] = getcpy(ct->c_file);
 176
 177     /*
 178      * If we've specified -(no)moreproc,
 179      * then just pass that along.
 180      */
 181     if (nomore) {
 182         vec[vecp++] = getcpy("-nomoreproc");
 183     } else if (progsw) {
 184         vec[vecp++] = getcpy("-moreproc");
 185         vec[vecp++] = getcpy(progsw);
 186     }
 187     vec[vecp] = NULL;
 188
 189     fflush (stdout);
 190
 191     for (i = 0; (child_id = fork()) == NOTOK && i < 5; i++)
 192         sleep (5);
 193
 194     switch (child_id) {
 195     case NOTOK:
 196         adios ("fork", "unable to");
 197         /* NOTREACHED */
 198
 199     case OK:
 200         execvp (file, vec);
 201         fprintf (stderr, "unable to exec ");
 202         perror (mhlproc);
 203         _exit (-1);
 204         /* NOTREACHED */
 205
 206     default:
 207         xpid = -child_id;
 208         break;
 209     }
 210
 211     arglist_free(file, vec);
 212 }
 213
 214
 215 /*
 216  * Switching routine.  Call the correct routine
 217  * based on content type.
 218  */
 219
 220 static int
 221 show_switch (CT ct, int serial, int alternate)
 222 {
 223     switch (ct->c_type) {
 224         case CT_MULTIPART:
 225             return show_multi (ct, serial, alternate);
 226
 227         case CT_MESSAGE:
 228             switch (ct->c_subtype) {
 229                 case MESSAGE_PARTIAL:
 230                     return show_partial (ct, serial, alternate);
 231
 232                 case MESSAGE_EXTERNAL:
 233                     return show_external (ct, serial, alternate);
 234
 235                 case MESSAGE_RFC822:
 236                 default:
 237                     return show_message_rfc822 (ct, serial, alternate);
 238             }
 239
 240         case CT_TEXT:
 241             return show_text (ct, serial, alternate);
 242
 243         case CT_AUDIO:
 244         case CT_IMAGE:
 245         case CT_VIDEO:
 246         case CT_APPLICATION:
 247             return show_content (ct, serial, alternate);
 248
 249         default:
 250             adios (NULL, "unknown content type %d", ct->c_type);
 251     }
 252
 253     return 0;   /* NOT REACHED */
 254 }
 255
 256
 257 /*
 258  * Generic method for displaying content
 259  */
 260
 261 static int
 262 show_content (CT ct, int serial, int alternate)
 263 {
 264     char *cp, buffer[BUFSIZ];
 265     CI ci = &ct->c_ctinfo;
 266
 267     /* Check for mhn-show-type/subtype */
 268     snprintf (buffer, sizeof(buffer), "%s-show-%s/%s",
 269                 invo_name, ci->ci_type, ci->ci_subtype);
 270     if ((cp = context_find (buffer)) && *cp != '\0')
 271         return show_content_aux (ct, serial, alternate, cp, NULL);
 272
 273     /* Check for mhn-show-type */
 274     snprintf (buffer, sizeof(buffer), "%s-show-%s", invo_name, ci->ci_type);
 275     if ((cp = context_find (buffer)) && *cp != '\0')
 276         return show_content_aux (ct, serial, alternate, cp, NULL);
 277
 278     if ((cp = ct->c_showproc))
 279         return show_content_aux (ct, serial, alternate, cp, NULL);
 280
 281     /* complain if we are not a part of a multipart/alternative */
 282     if (!alternate)
 283         content_error (NULL, ct, "don't know how to display content");
 284
 285     return NOTOK;
 286 }
 287
 288
 289 /*
 290  * Parse the display string for displaying generic content
 291  */
 292
 293 int
 294 show_content_aux (CT ct, int serial, int alternate, char *cp, char *cracked)
 295 {
 296     int fd, len, buflen, quoted;
 297     int xstdin, xlist, xpause, xtty;
 298     char *bp, *pp, *file, buffer[BUFSIZ];
 299     CI ci = &ct->c_ctinfo;
 300
 301     if (!ct->c_ceopenfnx) {
 302         if (!alternate)
 303             content_error (NULL, ct, "don't know how to decode content");
 304
 305         return NOTOK;
 306     }
 307
 308     file = NULL;
 309     if ((fd = (*ct->c_ceopenfnx) (ct, &file)) == NOTOK)
 310         return NOTOK;
 311     if (ct->c_showproc && !strcmp (ct->c_showproc, "true"))
 312         return (alternate ? DONE : OK);
 313
 314     xlist  = 0;
 315     xpause = 0;
 316     xstdin = 0;
 317     xtty   = 0;
 318
 319     if (cracked) {
 320         strncpy (buffer, cp, sizeof(buffer));
 321         goto got_command;
 322     }
 323
 324     /* get buffer ready to go */
 325     bp = buffer;
 326     buflen = sizeof(buffer) - 1;
 327     bp[0] = bp[buflen] = '\0';
 328     quoted = 0;
 329
 330     /* Now parse display string */
 331     for ( ; *cp && buflen > 0; cp++) {
 332         if (*cp == '%') {
 333             pp = bp;
 334
 335             switch (*++cp) {
 336             case 'a':
 337                 /* insert parameters from Content-Type field */
 338             {
 339                 char **ap, **ep;
 340                 char *s = "";
 341
 342                 for (ap = ci->ci_attrs, ep = ci->ci_values; *ap; ap++, ep++) {
 343                     snprintf (bp, buflen, "%s%s=\"%s\"", s, *ap, *ep);
 344                     len = strlen (bp);
 345                     bp += len;
 346                     buflen -= len;
 347                     s = " ";
 348                 }
 349             }
 350             break;
 351
 352             case 'd':
 353                 /* insert content description */
 354                 if (ct->c_descr) {
 355                     char *s;
 356
 357                     s = trimcpy (ct->c_descr);
 358                     strncpy (bp, s, buflen);
 359                     free (s);
 360                 }
 361                 break;
 362
 363             case 'e':
 364                 /* exclusive execution */
 365                 xtty = 1;
 366                 break;
 367
 368             case 'F':
 369                 /* %e, %f, and stdin is terminal not content */
 370                 xstdin = 1;
 371                 xtty = 1;
 372                 /* and fall... */
 373
 374             case 'f':
 375                 /* insert filename containing content */
 376                 snprintf (bp, buflen, "'%s'", file);
 377                 /* since we've quoted the file argument, set things up
 378                  * to look past it, to avoid problems with the quoting
 379                  * logic below.  (I know, I should figure out what's
 380                  * broken with the quoting logic, but..)
 381                  */
 382                 len = strlen(bp);
 383                 buflen -= len;
 384                 bp += len;
 385                 pp = bp;
 386                 break;
 387
 388             case 'p':
 389                 /* %l, and pause prior to displaying content */
 390                 xpause = pausesw;
 391                 /* and fall... */
 392
 393             case 'l':
 394                 /* display listing prior to displaying content */
 395                 xlist = !nolist;
 396                 break;
 397
 398             case 's':
 399                 /* insert subtype of content */
 400                 strncpy (bp, ci->ci_subtype, buflen);
 401                 break;
 402
 403             case '%':
 404                 /* insert character % */
 405                 goto raw;
 406
 407             default:
 408                 *bp++ = *--cp;
 409                 *bp = '\0';
 410                 buflen--;
 411                 continue;
 412             }
 413             len = strlen (bp);
 414             bp += len;
 415             buflen -= len;
 416
 417             /* Did we actually insert something? */
 418             if (bp != pp) {
 419                 /* Insert single quote if not inside quotes already */
 420                 if (!quoted && buflen) {
 421                     len = strlen (pp);
 422                     memmove (pp + 1, pp, len);
 423                     *pp++ = '\'';
 424                     buflen--;
 425                     bp++;
 426                 }
 427                 /* Escape existing quotes */
 428                 while ((pp = strchr (pp, '\'')) && buflen > 3) {
 429                     len = strlen (pp++);
 430                     memmove (pp + 3, pp, len);
 431                     *pp++ = '\\';
 432                     *pp++ = '\'';
 433                     *pp++ = '\'';
 434                     buflen -= 3;
 435                     bp += 3;
 436                 }
 437                 /* If pp is still set, that means we ran out of space. */
 438                 if (pp)
 439                     buflen = 0;
 440                 if (!quoted && buflen) {
 441                     *bp++ = '\'';
 442                     *bp = '\0';
 443                     buflen--;
 444                 }
 445             }
 446         } else {
 447 raw:
 448             *bp++ = *cp;
 449             *bp = '\0';
 450             buflen--;
 451
 452             if (*cp == '\'')
 453                 quoted = !quoted;
 454         }
 455     }
 456
 457     if (buflen <= 0 ||
 458         (ct->c_termproc && (size_t) buflen <= strlen(ct->c_termproc))) {
 459         /* content_error would provide a more useful error message
 460          * here, except that if we got overrun, it probably would
 461          * too.
 462          */
 463         fprintf(stderr, "Buffer overflow constructing show command!\n");
 464         return NOTOK;
 465     }
 466
 467     /* use charset string to modify display method */
 468     if (ct->c_termproc) {
 469         char term[BUFSIZ];
 470
 471         strncpy (term, buffer, sizeof(term));
 472         snprintf (buffer, sizeof(buffer), ct->c_termproc, term);
 473     }
 474
 475 got_command:
 476     return show_content_aux2 (ct, serial, alternate, cracked, buffer,
 477                               fd, xlist, xpause, xstdin, xtty);
 478 }
 479
 480
 481 /*
 482  * Routine to actually display the content
 483  */
 484
 485 static int
 486 show_content_aux2 (CT ct, int serial, int alternate, char *cracked, char *buffer,
 487                    int fd, int xlist, int xpause, int xstdin, int xtty)
 488 {
 489     pid_t child_id;
 490     int i;
 491     char *vec[4], exec[BUFSIZ + sizeof "exec "];
 492
 493     if (debugsw || cracked) {
 494         fflush (stdout);
 495
 496         fprintf (stderr, "%s msg %s", cracked ? "storing" : "show",
 497                  ct->c_file);
 498         if (ct->c_partno)
 499             fprintf (stderr, " part %s", ct->c_partno);
 500         if (cracked)
 501             fprintf (stderr, " using command (cd %s; %s)\n", cracked, buffer);
 502         else
 503             fprintf (stderr, " using command %s\n", buffer);
 504     }
 505
 506     if (xpid < 0 || (xtty && xpid)) {
 507         if (xpid < 0)
 508             xpid = -xpid;
 509         pidcheck(pidwait (xpid, NOTOK));
 510         xpid = 0;
 511     }
 512
 513     if (xlist) {
 514         char prompt[BUFSIZ];
 515
 516         if (ct->c_type == CT_MULTIPART)
 517             list_content (ct, -1, 1, 0, 0);
 518         else
 519             list_switch (ct, -1, 1, 0, 0);
 520
 521         if (xpause && isatty (fileno (stdout))) {
 522             int intr;
 523             SIGNAL_HANDLER istat;
 524
 525             if (SOprintf ("Press <return> to show content..."))
 526                 printf ("Press <return> to show content...");
 527
 528             istat = SIGNAL (SIGINT, intrser);
 529             if ((intr = sigsetjmp (intrenv, 1)) == OK) {
 530                 fflush (stdout);
 531                 prompt[0] = 0;
 532                 read (fileno (stdout), prompt, sizeof(prompt));
 533             }
 534             SIGNAL (SIGINT, istat);
 535             if (intr != OK || prompt[0] == 'n') {
 536                 (*ct->c_ceclosefnx) (ct);
 537                 return (alternate ? DONE : NOTOK);
 538             }
 539             if (prompt[0] == 'q') done(OK);
 540         }
 541     }
 542
 543     snprintf (exec, sizeof(exec), "exec %s", buffer);
 544
 545     vec[0] = "/bin/sh";
 546     vec[1] = "-c";
 547     vec[2] = exec;
 548     vec[3] = NULL;
 549
 550     fflush (stdout);
 551
 552     for (i = 0; (child_id = fork()) == NOTOK && i < 5; i++)
 553         sleep (5);
 554     switch (child_id) {
 555         case NOTOK:
 556             advise ("fork", "unable to");
 557             (*ct->c_ceclosefnx) (ct);
 558             return NOTOK;
 559
 560         case OK:
 561             if (cracked)
 562                 chdir (cracked);
 563             if (!xstdin)
 564                 dup2 (fd, 0);
 565             close (fd);
 566             execvp ("/bin/sh", vec);
 567             fprintf (stderr, "unable to exec ");
 568             perror ("/bin/sh");
 569             _exit (-1);
 570             /* NOTREACHED */
 571
 572         default:
 573             if (!serial) {
 574                 ct->c_pid = child_id;
 575                 if (xtty)
 576                     xpid = child_id;
 577             } else {
 578                 pidcheck (pidXwait (child_id, NULL));
 579             }
 580
 581             if (fd != NOTOK)
 582                 (*ct->c_ceclosefnx) (ct);
 583             return (alternate ? DONE : OK);
 584     }
 585 }
 586
 587
 588 /*
 589  * show content of type "text"
 590  */
 591
 592 static int
 593 show_text (CT ct, int serial, int alternate)
 594 {
 595     char *cp, buffer[BUFSIZ];
 596     CI ci = &ct->c_ctinfo;
 597
 598     /* Check for mhn-show-type/subtype */
 599     snprintf (buffer, sizeof(buffer), "%s-show-%s/%s",
 600                 invo_name, ci->ci_type, ci->ci_subtype);
 601     if ((cp = context_find (buffer)) && *cp != '\0')
 602         return show_content_aux (ct, serial, alternate, cp, NULL);
 603
 604     /* Check for mhn-show-type */
 605     snprintf (buffer, sizeof(buffer), "%s-show-%s", invo_name, ci->ci_type);
 606     if ((cp = context_find (buffer)) && *cp != '\0')
 607         return show_content_aux (ct, serial, alternate, cp, NULL);
 608
 609     /*
 610      * Use default method if content is text/plain, or if
 611      * if it is not a text part of a multipart/alternative
 612      */
 613     if (!alternate || ct->c_subtype == TEXT_PLAIN) {
 614         snprintf (buffer, sizeof(buffer), "%%p%s '%%F'", progsw ? progsw :
 615                 moreproc && *moreproc ? moreproc : DEFAULT_PAGER);
 616         cp = (ct->c_showproc = add (buffer, NULL));
 617         return show_content_aux (ct, serial, alternate, cp, NULL);
 618     }
 619
 620     return NOTOK;
 621 }
 622
 623
 624 /*
 625  * show message body of type "multipart"
 626  */
 627
 628 static int
 629 show_multi (CT ct, int serial, int alternate)
 630 {
 631     char *cp, buffer[BUFSIZ];
 632     CI ci = &ct->c_ctinfo;
 633
 634     /* Check for mhn-show-type/subtype */
 635     snprintf (buffer, sizeof(buffer), "%s-show-%s/%s",
 636                 invo_name, ci->ci_type, ci->ci_subtype);
 637     if ((cp = context_find (buffer)) && *cp != '\0')
 638         return show_multi_aux (ct, serial, alternate, cp);
 639
 640     /* Check for mhn-show-type */
 641     snprintf (buffer, sizeof(buffer), "%s-show-%s", invo_name, ci->ci_type);
 642     if ((cp = context_find (buffer)) && *cp != '\0')
 643         return show_multi_aux (ct, serial, alternate, cp);
 644
 645     if ((cp = ct->c_showproc))
 646         return show_multi_aux (ct, serial, alternate, cp);
 647
 648     /*
 649      * Use default method to display this multipart content.  Even
 650      * unknown types are displayable, since they're treated as mixed
 651      * per RFC 2046.
 652      */
 653     return show_multi_internal (ct, serial, alternate);
 654 }
 655
 656
 657 /*
 658  * show message body of subtypes of multipart that
 659  * we understand directly (mixed, alternate, etc...)
 660  */
 661
 662 static int
 663 show_multi_internal (CT ct, int serial, int alternate)
 664 {
 665     int alternating, nowalternate, nowserial, result;
 666     struct multipart *m = (struct multipart *) ct->c_ctparams;
 667     struct part *part;
 668     CT p;
 669     sigset_t set, oset;
 670
 671     alternating = 0;
 672     nowalternate = alternate;
 673
 674     if (ct->c_subtype == MULTI_PARALLEL) {
 675         nowserial = serialsw;
 676     } else if (ct->c_subtype == MULTI_ALTERNATE) {
 677         nowalternate = 1;
 678         alternating  = 1;
 679         nowserial = serial;
 680     } else {
 681         /*
 682          * multipart/mixed
 683          * mutlipart/digest
 684          * unknown subtypes of multipart (treat as mixed per rfc2046)
 685          */
 686         nowserial = serial;
 687     }
 688
 689     /* block a few signals */
 690     if (!nowserial) {
 691         sigemptyset (&set);
 692         sigaddset (&set, SIGHUP);
 693         sigaddset (&set, SIGINT);
 694         sigaddset (&set, SIGQUIT);
 695         sigaddset (&set, SIGTERM);
 696         sigprocmask (SIG_BLOCK, &set, &oset);
 697     }
 698
 699 /*
 700  * alternate   -> we are a part inside an multipart/alternative
 701  * alternating -> we are a multipart/alternative
 702  */
 703
 704     result = alternate ? NOTOK : OK;
 705
 706     for (part = m->mp_parts; part; part = part->mp_next) {
 707         p = part->mp_part;
 708
 709         if (part_ok (p, 1) && type_ok (p, 1)) {
 710             int inneresult;
 711
 712             inneresult = show_switch (p, nowserial, nowalternate);
 713             switch (inneresult) {
 714                 case NOTOK:
 715                     if (alternate && !alternating) {
 716                         result = NOTOK;
 717                         goto out;
 718                     }
 719                     continue;
 720
 721                 case OK:
 722                 case DONE:
 723                     if (alternating) {
 724                         result = DONE;
 725                         break;
 726                     }
 727                     if (alternate) {
 728                         alternate = nowalternate = 0;
 729                         if (result == NOTOK)
 730                             result = inneresult;
 731                     }
 732                     continue;
 733             }
 734             break;
 735         }
 736     }
 737
 738     if (alternating && !part) {
 739         if (!alternate)
 740             content_error (NULL, ct, "don't know how to display any of the contents");
 741         result = NOTOK;
 742         goto out;
 743     }
 744
 745     if (serial && !nowserial) {
 746         pid_t pid;
 747         int kids;
 748         int status;
 749
 750         kids = 0;
 751         for (part = m->mp_parts; part; part = part->mp_next) {
 752             p = part->mp_part;
 753
 754             if (p->c_pid > OK) {
 755                 if (kill (p->c_pid, 0) == NOTOK)
 756                     p->c_pid = 0;
 757                 else
 758                     kids++;
 759             }
 760         }
 761
 762         while (kids > 0 && (pid = wait (&status)) != NOTOK) {
 763             pidcheck (status);
 764
 765             for (part = m->mp_parts; part; part = part->mp_next) {
 766                 p = part->mp_part;
 767
 768                 if (xpid == pid)
 769                     xpid = 0;
 770                 if (p->c_pid == pid) {
 771                     p->c_pid = 0;
 772                     kids--;
 773                     break;
 774                 }
 775             }
 776         }
 777     }
 778
 779 out:
 780     if (!nowserial) {
 781         /* reset the signal mask */
 782         sigprocmask (SIG_SETMASK, &oset, &set);
 783     }
 784
 785     return result;
 786 }
 787
 788
 789 /*
 790  * Parse display string for multipart content
 791  * and use external program to display it.
 792  */
 793
 794 static int
 795 show_multi_aux (CT ct, int serial, int alternate, char *cp)
 796 {
 797     int len, buflen, quoted;
 798     int xlist, xpause, xtty;
 799     char *bp, *pp, *file, buffer[BUFSIZ];
 800     struct multipart *m = (struct multipart *) ct->c_ctparams;
 801     struct part *part;
 802     CI ci = &ct->c_ctinfo;
 803     CT p;
 804
 805     for (part = m->mp_parts; part; part = part->mp_next) {
 806         p = part->mp_part;
 807
 808         if (!p->c_ceopenfnx) {
 809             if (!alternate)
 810                 content_error (NULL, p, "don't know how to decode content");
 811             return NOTOK;
 812         }
 813
 814         if (p->c_storage == NULL) {
 815             file = NULL;
 816             if ((*p->c_ceopenfnx) (p, &file) == NOTOK)
 817                 return NOTOK;
 818
 819             /* I'm not sure if this is necessary? */
 820             p->c_storage = add (file, NULL);
 821
 822             if (p->c_showproc && !strcmp (p->c_showproc, "true"))
 823                 return (alternate ? DONE : OK);
 824             (*p->c_ceclosefnx) (p);
 825         }
 826     }
 827
 828     xlist     = 0;
 829     xpause    = 0;
 830     xtty      = 0;
 831
 832     /* get buffer ready to go */
 833     bp = buffer;
 834     buflen = sizeof(buffer) - 1;
 835     bp[0] = bp[buflen] = '\0';
 836     quoted = 0;
 837
 838     /* Now parse display string */
 839     for ( ; *cp && buflen > 0; cp++) {
 840         if (*cp == '%') {
 841             pp = bp;
 842             switch (*++cp) {
 843             case 'a':
 844                 /* insert parameters from Content-Type field */
 845             {
 846                 char **ap, **ep;
 847                 char *s = "";
 848
 849                 for (ap = ci->ci_attrs, ep = ci->ci_values; *ap; ap++, ep++) {
 850                     snprintf (bp, buflen, "%s%s=\"%s\"", s, *ap, *ep);
 851                     len = strlen (bp);
 852                     bp += len;
 853                     buflen -= len;
 854                     s = " ";
 855                 }
 856             }
 857             break;
 858
 859             case 'd':
 860                 /* insert content description */
 861                 if (ct->c_descr) {
 862                     char *s;
 863
 864                     s = trimcpy (ct->c_descr);
 865                     strncpy (bp, s, buflen);
 866                     free (s);
 867                 }
 868                 break;
 869
 870             case 'e':
 871                 /* exclusive execution */
 872                 xtty = 1;
 873                 break;
 874
 875             case 'F':
 876                 /* %e and %f */
 877                 xtty = 1;
 878                 /* and fall... */
 879
 880             case 'f':
 881                 /* insert filename(s) containing content */
 882             {
 883                 char *s = "";
 884
 885                 for (part = m->mp_parts; part; part = part->mp_next) {
 886                     p = part->mp_part;
 887
 888                     snprintf (bp, buflen, "%s'%s'", s, p->c_storage);
 889                     len = strlen (bp);
 890                     bp += len;
 891                     buflen -= len;
 892                     s = " ";
 893                 }
 894                 /* set our starting pointer back to bp, to avoid
 895                  * requoting the filenames we just added
 896                  */
 897                 pp = bp;
 898             }
 899             break;
 900
 901             case 'p':
 902                 /* %l, and pause prior to displaying content */
 903                 xpause = pausesw;
 904                 /* and fall... */
 905
 906             case 'l':
 907                 /* display listing prior to displaying content */
 908                 xlist = !nolist;
 909                 break;
 910
 911             case 's':
 912                 /* insert subtype of content */
 913                 strncpy (bp, ci->ci_subtype, buflen);
 914                 break;
 915
 916             case '%':
 917                 /* insert character % */
 918                 goto raw;
 919
 920             default:
 921                 *bp++ = *--cp;
 922                 *bp = '\0';
 923                 buflen--;
 924                 continue;
 925             }
 926             len = strlen (bp);
 927             bp += len;
 928             buflen -= len;
 929
 930             /* Did we actually insert something? */
 931             if (bp != pp) {
 932                 /* Insert single quote if not inside quotes already */
 933                 if (!quoted && buflen) {
 934                     len = strlen (pp);
 935                     memmove (pp + 1, pp, len);
 936                     *pp++ = '\'';
 937                     buflen--;
 938                     bp++;
 939                 }
 940                 /* Escape existing quotes */
 941                 while ((pp = strchr (pp, '\'')) && buflen > 3) {
 942                     len = strlen (pp++);
 943                     memmove (pp + 3, pp, len);
 944                     *pp++ = '\\';
 945                     *pp++ = '\'';
 946                     *pp++ = '\'';
 947                     buflen -= 3;
 948                     bp += 3;
 949                 }
 950                 /* If pp is still set, that means we ran out of space. */
 951                 if (pp)
 952                     buflen = 0;
 953                 if (!quoted && buflen) {
 954                     *bp++ = '\'';
 955                     *bp = '\0';
 956                     buflen--;
 957                 }
 958             }
 959         } else {
 960 raw:
 961             *bp++ = *cp;
 962             *bp = '\0';
 963             buflen--;
 964
 965             if (*cp == '\'')
 966                 quoted = !quoted;
 967         }
 968     }
 969
 970     if (buflen <= 0 ||
 971         (ct->c_termproc && buflen <= (ssize_t) strlen(ct->c_termproc))) {
 972         /* content_error would provide a more useful error message
 973          * here, except that if we got overrun, it probably would
 974          * too.
 975          */
 976         fprintf(stderr, "Buffer overflow constructing show command!\n");
 977         return NOTOK;
 978     }
 979
 980     /* use charset string to modify display method */
 981     if (ct->c_termproc) {
 982         char term[BUFSIZ];
 983
 984         strncpy (term, buffer, sizeof(term));
 985         snprintf (buffer, sizeof(buffer), ct->c_termproc, term);
 986     }
 987
 988     return show_content_aux2 (ct, serial, alternate, NULL, buffer,
 989                               NOTOK, xlist, xpause, 0, xtty);
 990 }
 991
 992
 993 /*
 994  * show content of type "message/rfc822"
 995  */
 996
 997 static int
 998 show_message_rfc822 (CT ct, int serial, int alternate)
 999 {
1000     char *cp, buffer[BUFSIZ];
1001     CI ci = &ct->c_ctinfo;
1002
1003     /* Check for mhn-show-type/subtype */
1004     snprintf (buffer, sizeof(buffer), "%s-show-%s/%s",
1005                 invo_name, ci->ci_type, ci->ci_subtype);
1006     if ((cp = context_find (buffer)) && *cp != '\0')
1007         return show_content_aux (ct, serial, alternate, cp, NULL);
1008
1009     /* Check for mhn-show-type */
1010     snprintf (buffer, sizeof(buffer), "%s-show-%s", invo_name, ci->ci_type);
1011     if ((cp = context_find (buffer)) && *cp != '\0')
1012         return show_content_aux (ct, serial, alternate, cp, NULL);
1013
1014     if ((cp = ct->c_showproc))
1015         return show_content_aux (ct, serial, alternate, cp, NULL);
1016
1017     /* default method for message/rfc822 */
1018     if (ct->c_subtype == MESSAGE_RFC822) {
1019         cp = (ct->c_showproc = add ("%pshow -file '%F'", NULL));
1020         return show_content_aux (ct, serial, alternate, cp, NULL);
1021     }
1022
1023     /* complain if we are not a part of a multipart/alternative */
1024     if (!alternate)
1025         content_error (NULL, ct, "don't know how to display content");
1026
1027     return NOTOK;
1028 }
1029
1030
1031 /*
1032  * Show content of type "message/partial".
1033  */
1034
1035 static int
1036 show_partial (CT ct, int serial, int alternate)
1037 {
1038     NMH_UNUSED (serial);
1039     NMH_UNUSED (alternate);
1040
1041     content_error (NULL, ct,
1042         "in order to display this message, you must reassemble it");
1043     return NOTOK;
1044 }
1045
1046
1047 /*
1048  * Show content of type "message/external".
1049  *
1050  * THE ERROR CHECKING IN THIS ONE IS NOT DONE YET.
1051  */
1052
1053 static int
1054 show_external (CT ct, int serial, int alternate)
1055 {
1056     struct exbody *e = (struct exbody *) ct->c_ctparams;
1057     CT p = e->eb_content;
1058
1059     if (!type_ok (p, 0))
1060         return OK;
1061
1062     return show_switch (p, serial, alternate);
1063 }
1064
1065
1066 static void
1067 intrser (int i)
1068 {
1069     NMH_UNUSED (i);
1070
1071     putchar ('\n');
1072     siglongjmp (intrenv, DONE);
1073 }