pith/mailcap.c

   1 #if !defined(lint) && !defined(DOS)
   2 static char rcsid[] = "$Id: mailcap.c 1012 2008-03-26 00:44:22Z hubert@u.washington.edu $";
   3 #endif
   4
   5 /*
   6  * ========================================================================
   7  * Copyright 2013-2017 Eduardo Chappa
   8  * Copyright 2006-2008 University of Washington
   9  *
  10  * Licensed under the Apache License, Version 2.0 (the "License");
  11  * you may not use this file except in compliance with the License.
  12  * You may obtain a copy of the License at
  13  *
  14  *     http://www.apache.org/licenses/LICENSE-2.0
  15  *
  16  * ========================================================================
  17  */
  18
  19 #include "../pith/headers.h"
  20 #include "../pith/mailcap.h"
  21 #include "../pith/init.h"
  22 #include "../pith/conf.h"
  23 #include "../pith/mimetype.h"
  24 #include "../pith/mimedesc.h"
  25 #include "../pith/status.h"
  26 #include "../pith/util.h"
  27 #include "../pith/readfile.h"
  28
  29 /*
  30  * We've decided not to implement the RFC1524 standard minimum path, because
  31  * some of us think it is harder to debug a problem when you may be misled
  32  * into looking at the wrong mailcap entry.  Likewise for MIME.Types files.
  33  */
  34 #if defined(DOS) || defined(OS2)
  35 #define MC_PATH_SEPARATOR ';'
  36 #define MC_USER_FILE      "MAILCAP"
  37 #define MC_STDPATH        NULL
  38 #else /* !DOS */
  39 #define MC_PATH_SEPARATOR ':'
  40 #define MC_USER_FILE      NULL
  41 #define MC_STDPATH         \
  42                 ".mailcap:/etc/mailcap:/usr/etc/mailcap:/usr/local/etc/mailcap"
  43 #endif /* !DOS */
  44
  45 #ifdef  _WINDOWS
  46 #define MC_ADD_TMP      " %s"
  47 #else
  48 #define MC_ADD_TMP      " < %s"
  49 #endif
  50
  51 typedef struct mcap_entry {
  52     struct mcap_entry *next;
  53     int                needsterminal;
  54     char              *contenttype;
  55     char              *command;
  56     char              *testcommand;
  57     char              *label;           /* unused */
  58     char              *printcommand;    /* unused */
  59 } MailcapEntry;
  60
  61 struct  mailcap_data {
  62     MailcapEntry *head, **tail;
  63     STRINGLIST   *raw;
  64 } MailcapData;
  65
  66 #define MC_TOKEN_MAX    64
  67
  68
  69 /*
  70  * Internal prototypes
  71  */
  72 void          mc_init(void);
  73 void          mc_process_file(char *);
  74 void          mc_parse_file(char *);
  75 int           mc_parse_line(char **, char **);
  76 int           mc_comment(char **);
  77 int           mc_token(char **, char **);
  78 void          mc_build_entry(char **);
  79 int           mc_sane_command(char *);
  80 MailcapEntry *mc_get_command(int, char *, BODY *, int, int *);
  81 int           mc_ctype_match(int, char *, char *);
  82 int           mc_passes_test(MailcapEntry *, int, char *, BODY *);
  83 char         *mc_bld_test_cmd(char *, int, char *, BODY *);
  84 char         *mc_cmd_bldr(char *, int, char *, BODY *, char *, char **);
  85 MailcapEntry *mc_new_entry(void);
  86 void          mc_free_entry(MailcapEntry **);
  87
  88
  89 char *
  90 mc_conf_path(char *def_path, char *env_path, char *user_file, int separator, char *stdpath)
  91 {
  92     char *path;
  93
  94     /* We specify MIMETYPES as a path override */
  95     if(def_path)
  96       /* there may need to be an override specific to pine */
  97       path = cpystr(def_path);
  98     else if(env_path)
  99       path = cpystr(env_path);
 100     else{
 101 #if defined(DOS) || defined(OS2)
 102         char *s;
 103
 104         /*
 105          * This gets interesting.  Since we don't have any standard location
 106          * for config/data files, look in the same directory as the PINERC
 107          * and the same dir as PINE.EXE.  This is similar to the UNIX
 108          * situation with personal config info coming before
 109          * potentially shared config data...
 110          */
 111         if(s = last_cmpnt(ps_global->pinerc)){
 112             strncpy(tmp_20k_buf+1000, ps_global->pinerc, MIN(s - ps_global->pinerc,SIZEOF_20KBUF-1000));
 113             tmp_20k_buf[1000+MIN(s - ps_global->pinerc,SIZEOF_20KBUF-1000-1)] = '\0';
 114         }
 115         else
 116           strncpy(tmp_20k_buf+1000, ".\\", SIZEOF_20KBUF-1000);
 117
 118         /* pinerc directory version of file */
 119         build_path(tmp_20k_buf+2000, tmp_20k_buf+1000, user_file, SIZEOF_20KBUF-2000);
 120         tmp_20k_buf[SIZEOF_20KBUF-1] = '\0';
 121
 122         /* pine.exe directory version of file */
 123         build_path(tmp_20k_buf+3000, ps_global->pine_dir, user_file, SIZEOF_20KBUF-3000);
 124         tmp_20k_buf[SIZEOF_20KBUF-1] = '\0';
 125
 126         /* combine them */
 127         snprintf(tmp_20k_buf, SIZEOF_20KBUF, "%s%c%s", tmp_20k_buf+2000, separator, tmp_20k_buf+3000);
 128
 129 #else   /* !DOS */
 130         build_path(tmp_20k_buf, ps_global->home_dir, stdpath, SIZEOF_20KBUF);
 131 #endif  /* !DOS */
 132         path = cpystr(tmp_20k_buf);
 133     }
 134
 135     return(path);
 136 }
 137
 138
 139 /*
 140  * mc_init - Run down the path gathering all the mailcap entries.
 141  *           Returns with the Mailcap list built.
 142  */
 143 void
 144 mc_init(void)
 145 {
 146     char *s,
 147          *pathcopy,
 148          *path,
 149           image_viewer[MAILTMPLEN];
 150
 151     if(MailcapData.raw)         /* already have the file? */
 152       return;
 153     else
 154       MailcapData.tail = &MailcapData.head;
 155
 156     dprint((5, "- mc_init -\n"));
 157
 158     pathcopy = mc_conf_path(ps_global->VAR_MAILCAP_PATH, getenv("MAILCAPS"),
 159                             MC_USER_FILE, MC_PATH_SEPARATOR, MC_STDPATH);
 160
 161     path = pathcopy;                    /* overloaded "path" */
 162
 163     /*
 164      * Insert an entry for the image-viewer variable from .pinerc, if present.
 165      */
 166     if(ps_global->VAR_IMAGE_VIEWER && *ps_global->VAR_IMAGE_VIEWER){
 167         MailcapEntry *mc = mc_new_entry();
 168
 169         snprintf(image_viewer, sizeof(image_viewer), "%s %%s", ps_global->VAR_IMAGE_VIEWER);
 170
 171         MailcapData.raw            = mail_newstringlist();
 172         MailcapData.raw->text.data = (unsigned char *) cpystr(image_viewer);
 173         mc->command                = (char *) MailcapData.raw->text.data;
 174         mc->contenttype            = "image/*";
 175         mc->label                  = "Alpine Image Viewer";
 176         dprint((5, "mailcap: using image-viewer=%s\n",
 177                    ps_global->VAR_IMAGE_VIEWER
 178                      ? ps_global->VAR_IMAGE_VIEWER : "?"));
 179     }
 180
 181     dprint((7, "mailcap: path: %s\n", path ? path : "?"));
 182     while(path){
 183         s = strindex(path, MC_PATH_SEPARATOR);
 184         if(s)
 185           *s++ = '\0';
 186         mc_process_file(path);
 187         path = s;
 188     }
 189
 190     if(pathcopy)
 191       fs_give((void **)&pathcopy);
 192
 193 #ifdef DEBUG
 194     if(debug >= 11){
 195         MailcapEntry *mc;
 196         int i = 0;
 197
 198         dprint((11, "Collected mailcap entries\n"));
 199         for(mc = MailcapData.head; mc; mc = mc->next){
 200
 201             dprint((11, "%d: ", i++));
 202             if(mc->label)
 203               dprint((11, "%s\n", mc->label ? mc->label : "?"));
 204             if(mc->contenttype)
 205               dprint((11, "   %s",
 206                      mc->contenttype ? mc->contenttype : "?"));
 207             if(mc->command)
 208               dprint((11, "   command: %s\n",
 209                      mc->command ? mc->command : "?"));
 210             if(mc->testcommand)
 211               dprint((11, "   testcommand: %s",
 212                      mc->testcommand ? mc->testcommand : "?"));
 213             if(mc->printcommand)
 214               dprint((11, "   printcommand: %s",
 215                      mc->printcommand ? mc->printcommand : "?"));
 216             dprint((11, "   needsterminal %d\n", mc->needsterminal));
 217         }
 218     }
 219 #endif /* DEBUG */
 220 }
 221
 222
 223 /*
 224  * Add all the entries from this file onto the Mailcap list.
 225  */
 226 void
 227 mc_process_file(char *file)
 228 {
 229     char filebuf[MAXPATH+1], *file_data;
 230
 231     dprint((5, "mailcap: process_file: %s\n", file ? file : "?"));
 232
 233     (void)strncpy(filebuf, file, MAXPATH);
 234     filebuf[MAXPATH] = '\0';
 235     file = fnexpand(filebuf, sizeof(filebuf));
 236     dprint((7, "mailcap: processing file: %s\n", file ? file : "?"));
 237     switch(is_writable_dir(file)){
 238       case 0: case 1: /* is a directory */
 239         dprint((1, "mailcap: %s is a directory, should be a file\n",
 240             file ? file : "?"));
 241         return;
 242
 243       case 2: /* ok */
 244         break;
 245
 246       case 3: /* doesn't exist */
 247         dprint((5, "mailcap: %s doesn't exist\n", file ? file : "?"));
 248         return;
 249
 250       default:
 251         alpine_panic("Programmer botch in mc_process_file");
 252         /*NOTREACHED*/
 253     }
 254
 255     if((file_data = read_file(file, READ_FROM_LOCALE)) != NULL){
 256         STRINGLIST *newsl, **sl;
 257
 258         /* Create a new container */
 259         newsl            = mail_newstringlist();
 260         newsl->text.data = (unsigned char *) file_data;
 261
 262         /* figure out where in the list it should go */
 263         for(sl = &MailcapData.raw; *sl; sl = &((*sl)->next))
 264           ;
 265
 266         *sl = newsl;                    /* Add it to the list */
 267
 268         mc_parse_file(file_data);       /* the process mailcap data */
 269     }
 270     else
 271       dprint((5, "mailcap: %s can't be read\n", file ? file : "?"));
 272 }
 273
 274
 275 void
 276 mc_parse_file(char *file)
 277 {
 278     char *tokens[MC_TOKEN_MAX];
 279
 280     while(mc_parse_line(&file, tokens))
 281       mc_build_entry(tokens);
 282 }
 283
 284
 285 int
 286 mc_parse_line(char **line, char **tokens)
 287 {
 288     char **tokenp = tokens;
 289
 290     while(mc_comment(line))             /* skip comment lines */
 291       ;
 292
 293     while(mc_token(tokenp, line))       /* collect ';' delim'd tokens */
 294       if(++tokenp - tokens >= MC_TOKEN_MAX)
 295         fatal("Ran out of tokens parsing mailcap file");        /* outch! */
 296
 297     *++tokenp = NULL;                   /* tie off list */
 298     return(*tokens != NULL);
 299 }
 300
 301
 302 /*
 303  * Retuns 1 if line is a comment, 0 otherwise
 304  */
 305 int
 306 mc_comment(char **line)
 307 {
 308     if(**line == '\n'){         /* blank line is a comment, too */
 309         (*line)++;
 310         return(1);
 311     }
 312
 313     if(**line == '#'){
 314         while(**line)                   /* !EOF */
 315           if(*++(*line) == '\n'){       /* EOL? */
 316               (*line)++;
 317               break;
 318           }
 319
 320         return(1);
 321     }
 322
 323     return(0);
 324 }
 325
 326
 327 /*
 328  * Retuns 0 if EOL, 1 otherwise
 329  */
 330 int
 331 mc_token(char **token, char **line)
 332 {
 333     int   rv = 0;
 334     char *start, *wsp = NULL;
 335
 336     *token = NULL;                      /* init the slot for this token */
 337
 338     /* skip leading white space */
 339     while(**line && isspace((unsigned char) **line))
 340       (*line)++;
 341
 342     start = *line;
 343
 344     /* Then see what's left */
 345     while(1)
 346       switch(**line){
 347         case ';' :                      /* End-Of-Token */
 348           rv = 1;                       /* let caller know more follows */
 349         case '\n' :                     /* EOL */
 350           if(wsp)
 351             *wsp = '\0';                /* truncate white space? */
 352           else
 353             *start = '\0';              /* if we have a token, tie it off  */
 354
 355           (*line)++;                    /* and get ready to parse next one */
 356
 357           if(rv == 1){                  /* ignore trailing semicolon */
 358               while(**line){
 359                   if(**line == '\n')
 360                     rv = 0;
 361
 362                   if(isspace((unsigned char) **line))
 363                     (*line)++;
 364                   else
 365                     break;
 366               }
 367           }
 368
 369         case '\0' :                     /* EOF */
 370           return(rv);
 371
 372         case '\\' :                     /* Quoted char */
 373           (*line)++;
 374 #if     defined(DOS) || defined(OS2)
 375           /*
 376            * RFC 1524 says that backslash is used to quote
 377            * the next character, but since backslash is part of pathnames
 378            * on DOS we're afraid people will not put double backslashes
 379            * in their mailcap files.  Therefore, we violate the RFC by
 380            * looking ahead to the next character.  If it looks like it
 381            * is just part of a pathname, then we consider a single
 382            * backslash to *not* be a quoting character, but a literal
 383            * backslash instead.
 384            *
 385            * SO:
 386            * If next char is any of these, treat the backslash
 387            * that preceded it like a regular character.
 388            */
 389           if(**line && isascii(**line)
 390              && (isalnum((unsigned char) **line) || strchr("_+-=~" , **line))){
 391               *start++ = '\\';
 392               wsp = NULL;
 393               break;
 394           }
 395           else
 396 #endif  /* !DOS */
 397
 398            if(**line == '\n'){          /* quoted line break */
 399                *start = ' ';
 400                (*line)++;               /* just move on */
 401                while(isspace((unsigned char) **line))
 402                  (*line)++;
 403
 404                break;
 405            }
 406            else if(**line == '%')       /* quoted '%' becomes "%%" */
 407              *--(*line) = '%';          /* overwrite '\' !! */
 408
 409            /* Fall thru and copy/advance pointers*/
 410
 411         default :
 412           if(!*token)
 413             *token = start;
 414
 415           *start = *(*line)++;
 416           wsp    = (isspace((unsigned char) *start) && !wsp) ? start : NULL;
 417           start++;
 418           break;
 419       }
 420 }
 421
 422
 423 void
 424 mc_build_entry(char **tokens)
 425 {
 426     MailcapEntry *mc;
 427
 428     if(!tokens[0]){
 429         dprint((5, "mailcap: missing content type!\n"));
 430         return;
 431     }
 432     else if(!tokens[1] || !mc_sane_command(tokens[1])){
 433         dprint((5, "mailcap: missing/bogus command!\n"));
 434         return;
 435     }
 436
 437     mc              = mc_new_entry();
 438     mc->contenttype = *tokens++;
 439     mc->command     = *tokens++;
 440
 441     dprint((9, "mailcap: content type: %s\n   command: %s\n",
 442                mc->contenttype ? mc->contenttype : "?",
 443                mc->command ? mc->command : "?"));
 444
 445     /* grok options  */
 446     for( ; *tokens; tokens++){
 447         char *arg;
 448
 449         /* legit value? */
 450         if(!isalnum((unsigned char) **tokens)){
 451             dprint((5, "Unknown parameter = \"%s\"", *tokens));
 452             continue;
 453         }
 454
 455         if((arg = strindex(*tokens, '=')) != NULL){
 456             *arg = ' ';
 457             while(arg > *tokens && isspace((unsigned char) arg[-1]))
 458               arg--;
 459
 460             *arg++ = '\0';              /* tie off parm arg */
 461             while(*arg && isspace((unsigned char) *arg))
 462               arg++;
 463
 464             if(!*arg)
 465               arg = NULL;
 466         }
 467
 468         if(!strucmp(*tokens, "needsterminal")){
 469             mc->needsterminal = 1;
 470             dprint((9, "mailcap: set needsterminal\n"));
 471         }
 472         else if(!strucmp(*tokens, "copiousoutput")){
 473             mc->needsterminal = 2;
 474             dprint((9, "mailcap: set copiousoutput\n"));
 475         }
 476         else if(arg && !strucmp(*tokens, "test")){
 477             mc->testcommand = arg;
 478             dprint((9, "mailcap: testcommand=%s\n",
 479                        mc->testcommand ? mc->testcommand : "?"));
 480         }
 481         else if(arg && !strucmp(*tokens, "description")){
 482             mc->label = arg;
 483             dprint((9, "mailcap: label=%s\n",
 484                    mc->label ? mc->label : "?"));
 485         }
 486         else if(arg && !strucmp(*tokens, "print")){
 487             mc->printcommand = arg;
 488             dprint((9, "mailcap: printcommand=%s\n",
 489                        mc->printcommand ? mc->printcommand : "?"));
 490         }
 491         else if(arg && !strucmp(*tokens, "compose")){
 492             /* not used */
 493             dprint((9, "mailcap: not using compose=%s\n",
 494                    arg ? arg : "?"));
 495         }
 496         else if(arg && !strucmp(arg, "composetyped")){
 497             /* not used */
 498             dprint((9, "mailcap: not using composetyped=%s\n",
 499                    arg ? arg : "?"));
 500         }
 501         else if(arg && !strucmp(arg, "textualnewlines")){
 502             /* not used */
 503             dprint((9,
 504                        "mailcap: not using texttualnewlines=%s\n",
 505                        arg ? arg : "?"));
 506         }
 507         else if(arg && !strucmp(arg, "edit")){
 508             /* not used */
 509             dprint((9, "mailcap: not using edit=%s\n",
 510                    arg ? arg : "?"));
 511         }
 512         else if(arg && !strucmp(arg, "x11-bitmap")){
 513             /* not used */
 514             dprint((9, "mailcap: not using x11-bitmap=%s\n",
 515                    arg ? arg : "?"));
 516         }
 517         else
 518           dprint((9, "mailcap: ignoring unknown flag: %s\n",
 519                      arg ? arg : "?"));
 520     }
 521 }
 522
 523
 524 /*
 525  * Tests for mailcap defined command's sanity
 526  */
 527 int
 528 mc_sane_command(char *command)
 529 {
 530     /* First, test that a command string actually exists */
 531     if(command && *command){
 532 #ifdef  LATER
 533         /*
 534          * NOTE: Maybe we'll do this later.  The problem is when the
 535          * mailcap's been misconfigured.  We then end up supressing
 536          * valuable output when the user actually tries to launch the
 537          * spec'd viewer.
 538          */
 539
 540         /* Second, Make sure we can get at it */
 541         if(can_access_in_path(getenv("PATH"), command,  EXECUTE_ACCESS) >= 0)
 542 #endif
 543         return(1);
 544     }
 545
 546     return(0);                  /* failed! */
 547 }
 548
 549
 550 /*
 551  * Returns the mailcap entry for type/subtype from the successfull
 552  * mailcap entry, or NULL if none.  Command string still contains % stuff.
 553  */
 554 MailcapEntry *
 555 mc_get_command(int type, char *subtype, BODY *body,
 556                int check_extension, int *sp_handlingp)
 557 {
 558     MailcapEntry *mc;
 559     char          tmp_subtype[256], tmp_ext[16], *ext = NULL;
 560
 561     dprint((5, "- mc_get_command(%s/%s) -\n",
 562                body_type_names(type),
 563                subtype ? subtype : "?"));
 564
 565     if(type == TYPETEXT
 566        && (!subtype || !strucmp(subtype, "plain"))
 567        && F_ON(F_SHOW_TEXTPLAIN_INT, ps_global))
 568       return(NULL);
 569
 570     mc_init();
 571
 572     if(check_extension){
 573         char     *fname;
 574         MT_MAP_T  e2b;
 575
 576         /*
 577          * Special handling for when we're looking at what's likely
 578          * binary application data. Look for a file name extension
 579          * that we might use to hook a helper app to.
 580          *
 581          * NOTE: This used to preclude an "app/o-s" mailcap entry
 582          *       since this took precedence.  Now that there are
 583          *       typically two scans through the check_extension
 584          *       mechanism, the mailcap entry now takes precedence.
 585          */
 586         if((fname = get_filename_parameter(NULL, 0, body, &e2b.from.ext)) != NULL
 587            && e2b.from.ext && e2b.from.ext[0]){
 588             if(strlen(e2b.from.ext) < sizeof(tmp_ext) - 2){
 589                 strncpy(ext = tmp_ext, e2b.from.ext - 1, sizeof(tmp_ext)); /* remember it */
 590                 tmp_ext[sizeof(tmp_ext)-1] = '\0';
 591                 if(mt_srch_mime_type(mt_srch_by_ext, &e2b)){
 592                     type = e2b.to.mime.type;            /* mapped type */
 593                     strncpy(subtype = tmp_subtype, e2b.to.mime.subtype,
 594                             sizeof(tmp_subtype)-1);
 595                     tmp_subtype[sizeof(tmp_subtype)-1] = '\0';
 596                     fs_give((void **) &e2b.to.mime.subtype);
 597                     body = NULL;                /* the params no longer apply */
 598                 }
 599             }
 600
 601             fs_give((void **) &fname);
 602         }
 603         else{
 604             if(fname)
 605               fs_give((void **) &fname);
 606
 607             return(NULL);
 608         }
 609     }
 610
 611     for(mc = MailcapData.head; mc; mc = mc->next)
 612       if(mc_ctype_match(type, subtype, mc->contenttype)
 613          && mc_passes_test(mc, type, subtype, body)){
 614           dprint((9,
 615                      "mc_get_command: type=%s/%s, command=%s\n",
 616                      body_type_names(type),
 617                      subtype ? subtype : "?",
 618                      mc->command ? mc->command : "?"));
 619           return(mc);
 620       }
 621
 622     if(mime_os_specific_access()){
 623         static MailcapEntry  fake_mc;
 624         static char          fake_cmd[1024];
 625         char                 tmp_mime_type[256];
 626
 627         memset(&fake_mc, 0, sizeof(MailcapEntry));
 628         fake_cmd[0] = '\0';
 629         fake_mc.command = fake_cmd;
 630
 631         snprintf(tmp_mime_type, sizeof(tmp_mime_type), "%s/%s", body_types[type], subtype);
 632         if(mime_get_os_mimetype_command(tmp_mime_type, ext, fake_cmd,
 633                                         sizeof(fake_cmd), check_extension, sp_handlingp))
 634           return(&fake_mc);
 635     }
 636
 637     return(NULL);
 638 }
 639
 640
 641 /*
 642  * Check whether the pattern "pat" matches this type/subtype.
 643  * Returns 1 if it does, 0 if not.
 644  */
 645 int
 646 mc_ctype_match(int type, char *subtype, char *pat)
 647 {
 648     char *type_name = body_type_names(type);
 649     int   len = strlen(type_name);
 650
 651     dprint((5, "mc_ctype_match: %s == %s / %s ?\n",
 652                pat ? pat : "?",
 653                type_name ? type_name : "?",
 654                subtype ? subtype : "?"));
 655
 656     return(!struncmp(type_name, pat, len)
 657            && ((pat[len] == '/'
 658                 && (!pat[len+1] || pat[len+1] == '*'
 659                     || !strucmp(subtype, &pat[len+1])))
 660                || !pat[len]));
 661 }
 662
 663
 664 /*
 665  * Run the test command for entry mc to see if this entry currently applies to
 666  * applies to this type/subtype.
 667  *
 668  * Returns 1 if it does pass test (exits with status 0), 0 otherwise.
 669  */
 670 int
 671 mc_passes_test(MailcapEntry *mc, int type, char *subtype, BODY *body)
 672 {
 673     char *cmd = NULL;
 674     int   rv;
 675
 676     dprint((5, "- mc_passes_test -\n"));
 677
 678     if(mc->testcommand
 679        && *mc->testcommand
 680        && !(cmd = mc_bld_test_cmd(mc->testcommand, type, subtype, body)))
 681       return(FALSE);    /* couldn't be built */
 682
 683     if(!mc->testcommand || !cmd || !*cmd){
 684         if(cmd)
 685           fs_give((void **)&cmd);
 686
 687         dprint((7, "no test command, so Pass\n"));
 688         return 1;
 689     }
 690
 691     rv = exec_mailcap_test_cmd(cmd);
 692     dprint((7, "mc_passes_test: \"%s\" %s (rv=%d)\n",
 693        cmd ? cmd : "?", rv ? "Failed" : "Passed", rv)) ;
 694
 695     fs_give((void **)&cmd);
 696
 697     return(!rv);
 698 }
 699
 700
 701 int
 702 mailcap_can_display(int type, char *subtype, BODY *body, int check_extension)
 703 {
 704     dprint((5, "- mailcap_can_display -\n"));
 705
 706     return(mc_get_command(type, subtype, body,
 707                           check_extension, NULL) != NULL);
 708 }
 709
 710
 711 MCAP_CMD_S *
 712 mailcap_build_command(int type, char *subtype, BODY *body,
 713                       char *tmp_file, int *needsterm, int chk_extension)
 714 {
 715     MailcapEntry *mc;
 716     char         *command, *err = NULL;
 717     MCAP_CMD_S   *mc_cmd = NULL;
 718     int           sp_handling = 0;
 719
 720     dprint((5, "- mailcap_build_command -\n"));
 721
 722     mc = mc_get_command(type, subtype, body, chk_extension, &sp_handling);
 723     if(!mc){
 724         q_status_message(SM_ORDER, 3, 4, "Error constructing viewer command");
 725         dprint((1,
 726                    "mailcap_build_command: no command string for %s/%s\n",
 727                    body_type_names(type), subtype ? subtype : "?"));
 728         return((MCAP_CMD_S *)NULL);
 729     }
 730
 731     if(needsterm)
 732       *needsterm = mc->needsterminal;
 733
 734     if(sp_handling)
 735       command = cpystr(mc->command);
 736     else if(!(command = mc_cmd_bldr(mc->command, type, subtype, body, tmp_file, &err)) && err && *err)
 737       q_status_message(SM_ORDER, 5, 5, err);
 738
 739     dprint((5, "built command: %s\n", command ? command : "?"));
 740
 741     if(command){
 742         mc_cmd = (MCAP_CMD_S *)fs_get(sizeof(MCAP_CMD_S));
 743         mc_cmd->command = command;
 744         mc_cmd->special_handling = sp_handling;
 745     }
 746     return(mc_cmd);
 747 }
 748
 749
 750 /*
 751  * mc_bld_test_cmd - build the command to test if the given type flies
 752  *
 753  *    mc_cmd_bldr's tmp_file argument is NULL as we're not going to
 754  *    decode and write each and every MIME segment's data to a temp file
 755  *    when no test's going to use the data anyway.
 756  */
 757 char *
 758 mc_bld_test_cmd(char *controlstring, int type, char *subtype, BODY *body)
 759 {
 760     return(mc_cmd_bldr(controlstring, type, subtype, body, NULL, NULL));
 761 }
 762
 763
 764 /*
 765  * mc_cmd_bldr - construct a command string to execute
 766  *
 767  *    If tmp_file is null, then the contents of the given MIME segment
 768  *    is not provided.  This is useful for building the "test=" string
 769  *    as it doesn't operate on the segment's data.
 770  *
 771  *    The return value is an alloc'd copy of the command to be executed.
 772  */
 773 char *
 774 mc_cmd_bldr(char *controlstring, int type, char *subtype,
 775             BODY *body, char *tmp_file, char **err)
 776 {
 777     char        *from, *to, *s, *parm;
 778     int          prefixed = 0, used_tmp_file = 0;
 779
 780     dprint((8, "- mc_cmd_bldr -\n"));
 781
 782     for(from = controlstring, to = tmp_20k_buf; *from; ++from){
 783         if(prefixed){                   /* previous char was % */
 784             prefixed = 0;
 785             switch(*from){
 786               case '%':                 /* turned \% into this earlier */
 787                 if(to-tmp_20k_buf < SIZEOF_20KBUF)
 788                   *to++ = '%';
 789
 790                 break;
 791
 792               case 's':                 /* insert tmp_file name in cmd */
 793                 if(tmp_file){
 794                     used_tmp_file = 1;
 795                     sstrncpy(&to, tmp_file, SIZEOF_20KBUF-(to-tmp_20k_buf));
 796                 }
 797                 else
 798                   dprint((1,
 799                              "mc_cmd_bldr: %%s in cmd but not supplied!\n"));
 800
 801                 break;
 802
 803               case 't':                 /* insert MIME type/subtype */
 804                 /* quote to prevent funny business */
 805                 if(to-tmp_20k_buf < SIZEOF_20KBUF)
 806                   *to++ = '\'';
 807
 808                 sstrncpy(&to, body_type_names(type), SIZEOF_20KBUF-(to-tmp_20k_buf));
 809
 810                 if(to-tmp_20k_buf < SIZEOF_20KBUF)
 811                   *to++ = '/';
 812
 813                 sstrncpy(&to, subtype, SIZEOF_20KBUF-(to-tmp_20k_buf));
 814
 815                 if(to-tmp_20k_buf < SIZEOF_20KBUF)
 816                   *to++ = '\'';
 817
 818                 break;
 819
 820               case '{':                 /* insert requested MIME param */
 821                 if(F_OFF(F_DO_MAILCAP_PARAM_SUBST, ps_global)){
 822                     int save;
 823
 824                     dprint((2, "mc_cmd_bldr: param subs %s\n",
 825                             from ? from : "?"));
 826                     if(err){
 827                         if((s = strindex(from, '}')) != NULL){
 828                           save = *++s;
 829                           *s = '\0';
 830                         }
 831
 832                         snprintf(tmp_20k_buf, SIZEOF_20KBUF,
 833                             "Mailcap: see hidden feature %.200s (%%%.200s)",
 834                             feature_list_name(F_DO_MAILCAP_PARAM_SUBST), from);
 835                         *err = tmp_20k_buf;
 836                         if(s)
 837                           *s = save;
 838                     }
 839
 840                     return(NULL);
 841                 }
 842
 843                 s = strindex(from, '}');
 844                 if(!s){
 845                     q_status_message1(SM_ORDER, 0, 4,
 846     "Ignoring ill-formed parameter reference in mailcap file: %.200s", from);
 847                     break;
 848                 }
 849
 850                 *s = '\0';
 851                 ++from;    /* from is the part inside the brackets now */
 852
 853                 parm = parameter_val(body ? body->parameter : NULL, from);
 854
 855                 dprint((9,
 856                            "mc_cmd_bldr: parameter %s = %s\n",
 857                            from ? from : "?", parm ? parm : "(not found)"));
 858
 859                 /*
 860                  * Quote parameter values for /bin/sh.
 861                  * Put single quotes around the whole thing but every time
 862                  * there is an actual single quote put it outside of the
 863                  * single quotes with a backslash in front of it.  So the
 864                  * parameter value  fred's car
 865                  * turns into       'fred'\''s car'
 866                  */
 867                 if(to-tmp_20k_buf < SIZEOF_20KBUF)
 868                   *to++ = '\'';  /* opening quote */
 869
 870                 if(parm){
 871                     char *p;
 872
 873                     /*
 874                      * Copy value, but quote single quotes for /bin/sh
 875                      * Backslash quote is ignored inside single quotes so
 876                      * have to put those outside of the single quotes.
 877                      * (The parm+1000 nonsense is to protect against
 878                      * malicious mail trying to overflow our buffer.)
 879                      *
 880                      * TCH - Change 2/8/1999
 881                      * Also quote the ` to prevent execution of arbitrary code
 882                      */
 883                     for(p = parm; *p && p < parm+1000; p++){
 884                         if((*p == '\'') || (*p == '`')){
 885                             if(to-tmp_20k_buf+4 < SIZEOF_20KBUF){
 886                                 *to++ = '\'';  /* closing quote */
 887                                 *to++ = '\\';
 888                                 *to++ = *p;    /* quoted character */
 889                                 *to++ = '\'';  /* opening quote */
 890                             }
 891                         }
 892                         else if(to-tmp_20k_buf < SIZEOF_20KBUF)
 893                           *to++ = *p;
 894                     }
 895
 896                     fs_give((void **) &parm);
 897                 }
 898
 899                 if(to-tmp_20k_buf < SIZEOF_20KBUF)
 900                   *to++ = '\'';  /* closing quote for /bin/sh */
 901
 902                 *s = '}'; /* restore */
 903                 from = s;
 904                 break;
 905
 906                 /*
 907                  * %n and %F are used by metamail to support otherwise
 908                  * unrecognized multipart Content-Types.  Pine does
 909                  * not use these since we're only dealing with the individual
 910                  * parts at this point.
 911                  */
 912               case 'n':
 913               case 'F':
 914               default:
 915                 dprint((9,
 916                    "Ignoring %s format code in mailcap file: %%%c\n",
 917                    (*from == 'n' || *from == 'F') ? "unimplemented"
 918                                                   : "unrecognized",
 919                    *from));
 920                 break;
 921             }
 922         }
 923         else if(*from == '%')           /* next char is special */
 924           prefixed = 1;
 925         else if(to-tmp_20k_buf < SIZEOF_20KBUF)         /* regular character, just copy */
 926           *to++ = *from;
 927     }
 928
 929     if(to-tmp_20k_buf < SIZEOF_20KBUF)
 930       *to = '\0';
 931
 932     tmp_20k_buf[SIZEOF_20KBUF-1] = '\0';
 933
 934     /*
 935      * file not specified, redirect to stdin
 936      */
 937     if(!used_tmp_file && tmp_file)
 938       snprintf(to, SIZEOF_20KBUF-(to-tmp_20k_buf), MC_ADD_TMP, tmp_file);
 939
 940     return(cpystr(tmp_20k_buf));
 941 }
 942
 943
 944 /*
 945  *
 946  */
 947 MailcapEntry *
 948 mc_new_entry(void)
 949 {
 950     MailcapEntry *mc = (MailcapEntry *) fs_get(sizeof(MailcapEntry));
 951     memset(mc, 0, sizeof(MailcapEntry));
 952     *MailcapData.tail = mc;
 953     MailcapData.tail  = &mc->next;
 954     return(mc);
 955 }
 956
 957
 958 /*
 959  * Free a list of mailcap entries
 960  */
 961 void
 962 mc_free_entry(MailcapEntry **mc)
 963 {
 964     if(mc && *mc){
 965         mc_free_entry(&(*mc)->next);
 966         fs_give((void **) mc);
 967     }
 968 }
 969
 970
 971 void
 972 mailcap_free(void)
 973 {
 974     mail_free_stringlist(&MailcapData.raw);
 975     mc_free_entry(&MailcapData.head);
 976 }