bin/ed/main.c

   1 /* main.c: This file contains the main control and user-interface routines
   2    for the ed line editor. */
   3 /*-
   4  * Copyright (c) 1993 Andrew Moore, Talke Studio.
   5  * 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  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #ifndef lint
  30 #if 0
  31 static const char copyright[] =
  32 "@(#) Copyright (c) 1993 Andrew Moore, Talke Studio. \n\
  33  All rights reserved.\n";
  34 #endif
  35 #endif /* not lint */
  36
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD$");
  39
  40 /*
  41  * CREDITS
  42  *
  43  *      This program is based on the editor algorithm described in
  44  *      Brian W. Kernighan and P. J. Plauger's book "Software Tools
  45  *      in Pascal," Addison-Wesley, 1981.
  46  *
  47  *      The buffering algorithm is attributed to Rodney Ruddock of
  48  *      the University of Guelph, Guelph, Ontario.
  49  *
  50  *      The cbc.c encryption code is adapted from
  51  *      the bdes program by Matt Bishop of Dartmouth College,
  52  *      Hanover, NH.
  53  *
  54  */
  55
  56 #include <sys/types.h>
  57
  58 #include <sys/ioctl.h>
  59 #include <sys/wait.h>
  60 #include <ctype.h>
  61 #include <locale.h>
  62 #include <pwd.h>
  63 #include <setjmp.h>
  64
  65 #include "ed.h"
  66
  67
  68 #ifdef _POSIX_SOURCE
  69 sigjmp_buf env;
  70 #else
  71 jmp_buf env;
  72 #endif
  73
  74 /* static buffers */
  75 char stdinbuf[1];               /* stdin buffer */
  76 char *shcmd;                    /* shell command buffer */
  77 int shcmdsz;                    /* shell command buffer size */
  78 int shcmdi;                     /* shell command buffer index */
  79 char *ibuf;                     /* ed command-line buffer */
  80 int ibufsz;                     /* ed command-line buffer size */
  81 char *ibufp;                    /* pointer to ed command-line buffer */
  82
  83 /* global flags */
  84 int des = 0;                    /* if set, use crypt(3) for i/o */
  85 int garrulous = 0;              /* if set, print all error messages */
  86 int isbinary;                   /* if set, buffer contains ASCII NULs */
  87 int isglobal;                   /* if set, doing a global command */
  88 int modified;                   /* if set, buffer modified since last write */
  89 int mutex = 0;                  /* if set, signals set "sigflags" */
  90 int red = 0;                    /* if set, restrict shell/directory access */
  91 int scripted = 0;               /* if set, suppress diagnostics */
  92 int sigflags = 0;               /* if set, signals received while mutex set */
  93 int sigactive = 0;              /* if set, signal handlers are enabled */
  94
  95 char old_filename[PATH_MAX] = "";       /* default filename */
  96 long current_addr;              /* current address in editor buffer */
  97 long addr_last;                 /* last address in editor buffer */
  98 int lineno;                     /* script line number */
  99 const char *prompt;             /* command-line prompt */
 100 const char *dps = "*";          /* default command-line prompt */
 101
 102 const char usage[] = "usage: %s [-] [-sx] [-p string] [file]\n";
 103
 104 /* ed: line editor */
 105 int
 106 main(volatile int argc, char ** volatile argv)
 107 {
 108         int c, n;
 109         long status = 0;
 110
 111         (void)setlocale(LC_ALL, "");
 112
 113         red = (n = strlen(argv[0])) > 2 && argv[0][n - 3] == 'r';
 114 top:
 115         while ((c = getopt(argc, argv, "p:sx")) != -1)
 116                 switch(c) {
 117                 case 'p':                               /* set prompt */
 118                         prompt = optarg;
 119                         break;
 120                 case 's':                               /* run script */
 121                         scripted = 1;
 122                         break;
 123                 case 'x':                               /* use crypt */
 124 #ifdef DES
 125                         des = get_keyword();
 126 #else
 127                         fprintf(stderr, "crypt unavailable\n?\n");
 128 #endif
 129                         break;
 130
 131                 default:
 132                         fprintf(stderr, usage, red ? "red" : "ed");
 133                         exit(1);
 134                 }
 135         argv += optind;
 136         argc -= optind;
 137         if (argc && **argv == '-') {
 138                 scripted = 1;
 139                 if (argc > 1) {
 140                         optind = 1;
 141                         goto top;
 142                 }
 143                 argv++;
 144                 argc--;
 145         }
 146         /* assert: reliable signals! */
 147 #ifdef SIGWINCH
 148         handle_winch(SIGWINCH);
 149         if (isatty(0)) signal(SIGWINCH, handle_winch);
 150 #endif
 151         signal(SIGHUP, signal_hup);
 152         signal(SIGQUIT, SIG_IGN);
 153         signal(SIGINT, signal_int);
 154 #ifdef _POSIX_SOURCE
 155         if ((status = sigsetjmp(env, 1)))
 156 #else
 157         if ((status = setjmp(env)))
 158 #endif
 159         {
 160                 fputs("\n?\n", stderr);
 161                 errmsg = "interrupt";
 162         } else {
 163                 init_buffers();
 164                 sigactive = 1;                  /* enable signal handlers */
 165                 if (argc && **argv && is_legal_filename(*argv)) {
 166                         if (read_file(*argv, 0) < 0 && !isatty(0))
 167                                 quit(2);
 168                         else if (**argv != '!')
 169                                 if (strlcpy(old_filename, *argv, sizeof(old_filename))
 170                                     >= sizeof(old_filename))
 171                                         quit(2);
 172                 } else if (argc) {
 173                         fputs("?\n", stderr);
 174                         if (**argv == '\0')
 175                                 errmsg = "invalid filename";
 176                         if (!isatty(0))
 177                                 quit(2);
 178                 }
 179         }
 180         for (;;) {
 181                 if (status < 0 && garrulous)
 182                         fprintf(stderr, "%s\n", errmsg);
 183                 if (prompt) {
 184                         printf("%s", prompt);
 185                         fflush(stdout);
 186                 }
 187                 if ((n = get_tty_line()) < 0) {
 188                         status = ERR;
 189                         continue;
 190                 } else if (n == 0) {
 191                         if (modified && !scripted) {
 192                                 fputs("?\n", stderr);
 193                                 errmsg = "warning: file modified";
 194                                 if (!isatty(0)) {
 195                                         if (garrulous)
 196                                                 fprintf(stderr,
 197                                                     "script, line %d: %s\n",
 198                                                     lineno, errmsg);
 199                                         quit(2);
 200                                 }
 201                                 clearerr(stdin);
 202                                 modified = 0;
 203                                 status = EMOD;
 204                                 continue;
 205                         } else
 206                                 quit(0);
 207                 } else if (ibuf[n - 1] != '\n') {
 208                         /* discard line */
 209                         errmsg = "unexpected end-of-file";
 210                         clearerr(stdin);
 211                         status = ERR;
 212                         continue;
 213                 }
 214                 isglobal = 0;
 215                 if ((status = extract_addr_range()) >= 0 &&
 216                     (status = exec_command()) >= 0)
 217                         if (!status ||
 218                             (status = display_lines(current_addr, current_addr,
 219                                 status)) >= 0)
 220                                 continue;
 221                 switch (status) {
 222                 case EOF:
 223                         quit(0);
 224                 case EMOD:
 225                         modified = 0;
 226                         fputs("?\n", stderr);           /* give warning */
 227                         errmsg = "warning: file modified";
 228                         if (!isatty(0)) {
 229                                 if (garrulous)
 230                                         fprintf(stderr, "script, line %d: %s\n",
 231                                             lineno, errmsg);
 232                                 quit(2);
 233                         }
 234                         break;
 235                 case FATAL:
 236                         if (!isatty(0)) {
 237                                 if (garrulous)
 238                                         fprintf(stderr, "script, line %d: %s\n",
 239                                             lineno, errmsg);
 240                         } else if (garrulous)
 241                                 fprintf(stderr, "%s\n", errmsg);
 242                         quit(3);
 243                 default:
 244                         fputs("?\n", stderr);
 245                         if (!isatty(0)) {
 246                                 if (garrulous)
 247                                         fprintf(stderr, "script, line %d: %s\n",
 248                                             lineno, errmsg);
 249                                 quit(2);
 250                         }
 251                         break;
 252                 }
 253         }
 254         /*NOTREACHED*/
 255 }
 256
 257 long first_addr, second_addr, addr_cnt;
 258
 259 /* extract_addr_range: get line addresses from the command buffer until an
 260    illegal address is seen; return status */
 261 int
 262 extract_addr_range(void)
 263 {
 264         long addr;
 265
 266         addr_cnt = 0;
 267         first_addr = second_addr = current_addr;
 268         while ((addr = next_addr()) >= 0) {
 269                 addr_cnt++;
 270                 first_addr = second_addr;
 271                 second_addr = addr;
 272                 if (*ibufp != ',' && *ibufp != ';')
 273                         break;
 274                 else if (*ibufp++ == ';')
 275                         current_addr = addr;
 276         }
 277         if ((addr_cnt = min(addr_cnt, 2)) == 1 || second_addr != addr)
 278                 first_addr = second_addr;
 279         return (addr == ERR) ? ERR : 0;
 280 }
 281
 282
 283 #define SKIP_BLANKS() while (isspace((unsigned char)*ibufp) && *ibufp != '\n') ibufp++
 284
 285 #define MUST_BE_FIRST() do {                                    \
 286         if (!first) {                                           \
 287                 errmsg = "invalid address";                     \
 288                 return ERR;                                     \
 289         }                                                       \
 290 } while (0)
 291
 292 /*  next_addr: return the next line address in the command buffer */
 293 long
 294 next_addr(void)
 295 {
 296         const char *hd;
 297         long addr = current_addr;
 298         long n;
 299         int first = 1;
 300         int c;
 301
 302         SKIP_BLANKS();
 303         for (hd = ibufp;; first = 0)
 304                 switch (c = *ibufp) {
 305                 case '+':
 306                 case '\t':
 307                 case ' ':
 308                 case '-':
 309                 case '^':
 310                         ibufp++;
 311                         SKIP_BLANKS();
 312                         if (isdigit((unsigned char)*ibufp)) {
 313                                 STRTOL(n, ibufp);
 314                                 addr += (c == '-' || c == '^') ? -n : n;
 315                         } else if (!isspace((unsigned char)c))
 316                                 addr += (c == '-' || c == '^') ? -1 : 1;
 317                         break;
 318                 case '0': case '1': case '2':
 319                 case '3': case '4': case '5':
 320                 case '6': case '7': case '8': case '9':
 321                         MUST_BE_FIRST();
 322                         STRTOL(addr, ibufp);
 323                         break;
 324                 case '.':
 325                 case '$':
 326                         MUST_BE_FIRST();
 327                         ibufp++;
 328                         addr = (c == '.') ? current_addr : addr_last;
 329                         break;
 330                 case '/':
 331                 case '?':
 332                         MUST_BE_FIRST();
 333                         if ((addr = get_matching_node_addr(
 334                             get_compiled_pattern(), c == '/')) < 0)
 335                                 return ERR;
 336                         else if (c == *ibufp)
 337                                 ibufp++;
 338                         break;
 339                 case '\'':
 340                         MUST_BE_FIRST();
 341                         ibufp++;
 342                         if ((addr = get_marked_node_addr(*ibufp++)) < 0)
 343                                 return ERR;
 344                         break;
 345                 case '%':
 346                 case ',':
 347                 case ';':
 348                         if (first) {
 349                                 ibufp++;
 350                                 addr_cnt++;
 351                                 second_addr = (c == ';') ? current_addr : 1;
 352                                 addr = addr_last;
 353                                 break;
 354                         }
 355                         /* FALLTHROUGH */
 356                 default:
 357                         if (ibufp == hd)
 358                                 return EOF;
 359                         else if (addr < 0 || addr_last < addr) {
 360                                 errmsg = "invalid address";
 361                                 return ERR;
 362                         } else
 363                                 return addr;
 364                 }
 365         /* NOTREACHED */
 366 }
 367
 368
 369 #ifdef BACKWARDS
 370 /* GET_THIRD_ADDR: get a legal address from the command buffer */
 371 #define GET_THIRD_ADDR(addr) \
 372 { \
 373         long ol1, ol2; \
 374 \
 375         ol1 = first_addr, ol2 = second_addr; \
 376         if (extract_addr_range() < 0) \
 377                 return ERR; \
 378         else if (addr_cnt == 0) { \
 379                 errmsg = "destination expected"; \
 380                 return ERR; \
 381         } else if (second_addr < 0 || addr_last < second_addr) { \
 382                 errmsg = "invalid address"; \
 383                 return ERR; \
 384         } \
 385         addr = second_addr; \
 386         first_addr = ol1, second_addr = ol2; \
 387 }
 388 #else   /* BACKWARDS */
 389 /* GET_THIRD_ADDR: get a legal address from the command buffer */
 390 #define GET_THIRD_ADDR(addr) \
 391 { \
 392         long ol1, ol2; \
 393 \
 394         ol1 = first_addr, ol2 = second_addr; \
 395         if (extract_addr_range() < 0) \
 396                 return ERR; \
 397         if (second_addr < 0 || addr_last < second_addr) { \
 398                 errmsg = "invalid address"; \
 399                 return ERR; \
 400         } \
 401         addr = second_addr; \
 402         first_addr = ol1, second_addr = ol2; \
 403 }
 404 #endif
 405
 406
 407 /* GET_COMMAND_SUFFIX: verify the command suffix in the command buffer */
 408 #define GET_COMMAND_SUFFIX() { \
 409         int done = 0; \
 410         do { \
 411                 switch(*ibufp) { \
 412                 case 'p': \
 413                         gflag |= GPR, ibufp++; \
 414                         break; \
 415                 case 'l': \
 416                         gflag |= GLS, ibufp++; \
 417                         break; \
 418                 case 'n': \
 419                         gflag |= GNP, ibufp++; \
 420                         break; \
 421                 default: \
 422                         done++; \
 423                 } \
 424         } while (!done); \
 425         if (*ibufp++ != '\n') { \
 426                 errmsg = "invalid command suffix"; \
 427                 return ERR; \
 428         } \
 429 }
 430
 431
 432 /* sflags */
 433 #define SGG 001         /* complement previous global substitute suffix */
 434 #define SGP 002         /* complement previous print suffix */
 435 #define SGR 004         /* use last regex instead of last pat */
 436 #define SGF 010         /* repeat last substitution */
 437
 438 int patlock = 0;        /* if set, pattern not freed by get_compiled_pattern() */
 439
 440 long rows = 22;         /* scroll length: ws_row - 2 */
 441
 442 /* exec_command: execute the next command in command buffer; return print
 443    request, if any */
 444 int
 445 exec_command(void)
 446 {
 447         static pattern_t *pat = NULL;
 448         static int sgflag = 0;
 449         static long sgnum = 0;
 450
 451         pattern_t *tpat;
 452         char *fnp;
 453         int gflag = 0;
 454         int sflags = 0;
 455         long addr = 0;
 456         int n = 0;
 457         int c;
 458
 459         SKIP_BLANKS();
 460         switch(c = *ibufp++) {
 461         case 'a':
 462                 GET_COMMAND_SUFFIX();
 463                 if (!isglobal) clear_undo_stack();
 464                 if (append_lines(second_addr) < 0)
 465                         return ERR;
 466                 break;
 467         case 'c':
 468                 if (check_addr_range(current_addr, current_addr) < 0)
 469                         return ERR;
 470                 GET_COMMAND_SUFFIX();
 471                 if (!isglobal) clear_undo_stack();
 472                 if (delete_lines(first_addr, second_addr) < 0 ||
 473                     append_lines(current_addr) < 0)
 474                         return ERR;
 475                 break;
 476         case 'd':
 477                 if (check_addr_range(current_addr, current_addr) < 0)
 478                         return ERR;
 479                 GET_COMMAND_SUFFIX();
 480                 if (!isglobal) clear_undo_stack();
 481                 if (delete_lines(first_addr, second_addr) < 0)
 482                         return ERR;
 483                 else if ((addr = INC_MOD(current_addr, addr_last)) != 0)
 484                         current_addr = addr;
 485                 break;
 486         case 'e':
 487                 if (modified && !scripted)
 488                         return EMOD;
 489                 /* FALLTHROUGH */
 490         case 'E':
 491                 if (addr_cnt > 0) {
 492                         errmsg = "unexpected address";
 493                         return ERR;
 494                 } else if (!isspace((unsigned char)*ibufp)) {
 495                         errmsg = "unexpected command suffix";
 496                         return ERR;
 497                 } else if ((fnp = get_filename()) == NULL)
 498                         return ERR;
 499                 GET_COMMAND_SUFFIX();
 500                 if (delete_lines(1, addr_last) < 0)
 501                         return ERR;
 502                 clear_undo_stack();
 503                 if (close_sbuf() < 0)
 504                         return ERR;
 505                 else if (open_sbuf() < 0)
 506                         return FATAL;
 507                 if (*fnp && *fnp != '!') strcpy(old_filename, fnp);
 508 #ifdef BACKWARDS
 509                 if (*fnp == '\0' && *old_filename == '\0') {
 510                         errmsg = "no current filename";
 511                         return ERR;
 512                 }
 513 #endif
 514                 if (read_file(*fnp ? fnp : old_filename, 0) < 0)
 515                         return ERR;
 516                 clear_undo_stack();
 517                 modified = 0;
 518                 u_current_addr = u_addr_last = -1;
 519                 break;
 520         case 'f':
 521                 if (addr_cnt > 0) {
 522                         errmsg = "unexpected address";
 523                         return ERR;
 524                 } else if (!isspace((unsigned char)*ibufp)) {
 525                         errmsg = "unexpected command suffix";
 526                         return ERR;
 527                 } else if ((fnp = get_filename()) == NULL)
 528                         return ERR;
 529                 else if (*fnp == '!') {
 530                         errmsg = "invalid redirection";
 531                         return ERR;
 532                 }
 533                 GET_COMMAND_SUFFIX();
 534                 if (*fnp) strcpy(old_filename, fnp);
 535                 printf("%s\n", strip_escapes(old_filename));
 536                 break;
 537         case 'g':
 538         case 'v':
 539         case 'G':
 540         case 'V':
 541                 if (isglobal) {
 542                         errmsg = "cannot nest global commands";
 543                         return ERR;
 544                 } else if (check_addr_range(1, addr_last) < 0)
 545                         return ERR;
 546                 else if (build_active_list(c == 'g' || c == 'G') < 0)
 547                         return ERR;
 548                 else if ((n = (c == 'G' || c == 'V')))
 549                         GET_COMMAND_SUFFIX();
 550                 isglobal++;
 551                 if (exec_global(n, gflag) < 0)
 552                         return ERR;
 553                 break;
 554         case 'h':
 555                 if (addr_cnt > 0) {
 556                         errmsg = "unexpected address";
 557                         return ERR;
 558                 }
 559                 GET_COMMAND_SUFFIX();
 560                 if (*errmsg) fprintf(stderr, "%s\n", errmsg);
 561                 break;
 562         case 'H':
 563                 if (addr_cnt > 0) {
 564                         errmsg = "unexpected address";
 565                         return ERR;
 566                 }
 567                 GET_COMMAND_SUFFIX();
 568                 if ((garrulous = 1 - garrulous) && *errmsg)
 569                         fprintf(stderr, "%s\n", errmsg);
 570                 break;
 571         case 'i':
 572                 if (second_addr == 0) {
 573                         errmsg = "invalid address";
 574                         return ERR;
 575                 }
 576                 GET_COMMAND_SUFFIX();
 577                 if (!isglobal) clear_undo_stack();
 578                 if (append_lines(second_addr - 1) < 0)
 579                         return ERR;
 580                 break;
 581         case 'j':
 582                 if (check_addr_range(current_addr, current_addr + 1) < 0)
 583                         return ERR;
 584                 GET_COMMAND_SUFFIX();
 585                 if (!isglobal) clear_undo_stack();
 586                 if (first_addr != second_addr &&
 587                     join_lines(first_addr, second_addr) < 0)
 588                         return ERR;
 589                 break;
 590         case 'k':
 591                 c = *ibufp++;
 592                 if (second_addr == 0) {
 593                         errmsg = "invalid address";
 594                         return ERR;
 595                 }
 596                 GET_COMMAND_SUFFIX();
 597                 if (mark_line_node(get_addressed_line_node(second_addr), c) < 0)
 598                         return ERR;
 599                 break;
 600         case 'l':
 601                 if (check_addr_range(current_addr, current_addr) < 0)
 602                         return ERR;
 603                 GET_COMMAND_SUFFIX();
 604                 if (display_lines(first_addr, second_addr, gflag | GLS) < 0)
 605                         return ERR;
 606                 gflag = 0;
 607                 break;
 608         case 'm':
 609                 if (check_addr_range(current_addr, current_addr) < 0)
 610                         return ERR;
 611                 GET_THIRD_ADDR(addr);
 612                 if (first_addr <= addr && addr < second_addr) {
 613                         errmsg = "invalid destination";
 614                         return ERR;
 615                 }
 616                 GET_COMMAND_SUFFIX();
 617                 if (!isglobal) clear_undo_stack();
 618                 if (move_lines(addr) < 0)
 619                         return ERR;
 620                 break;
 621         case 'n':
 622                 if (check_addr_range(current_addr, current_addr) < 0)
 623                         return ERR;
 624                 GET_COMMAND_SUFFIX();
 625                 if (display_lines(first_addr, second_addr, gflag | GNP) < 0)
 626                         return ERR;
 627                 gflag = 0;
 628                 break;
 629         case 'p':
 630                 if (check_addr_range(current_addr, current_addr) < 0)
 631                         return ERR;
 632                 GET_COMMAND_SUFFIX();
 633                 if (display_lines(first_addr, second_addr, gflag | GPR) < 0)
 634                         return ERR;
 635                 gflag = 0;
 636                 break;
 637         case 'P':
 638                 if (addr_cnt > 0) {
 639                         errmsg = "unexpected address";
 640                         return ERR;
 641                 }
 642                 GET_COMMAND_SUFFIX();
 643                 prompt = prompt ? NULL : optarg ? optarg : dps;
 644                 break;
 645         case 'q':
 646         case 'Q':
 647                 if (addr_cnt > 0) {
 648                         errmsg = "unexpected address";
 649                         return ERR;
 650                 }
 651                 GET_COMMAND_SUFFIX();
 652                 gflag =  (modified && !scripted && c == 'q') ? EMOD : EOF;
 653                 break;
 654         case 'r':
 655                 if (!isspace((unsigned char)*ibufp)) {
 656                         errmsg = "unexpected command suffix";
 657                         return ERR;
 658                 } else if (addr_cnt == 0)
 659                         second_addr = addr_last;
 660                 if ((fnp = get_filename()) == NULL)
 661                         return ERR;
 662                 GET_COMMAND_SUFFIX();
 663                 if (!isglobal) clear_undo_stack();
 664                 if (*old_filename == '\0' && *fnp != '!')
 665                         strcpy(old_filename, fnp);
 666 #ifdef BACKWARDS
 667                 if (*fnp == '\0' && *old_filename == '\0') {
 668                         errmsg = "no current filename";
 669                         return ERR;
 670                 }
 671 #endif
 672                 if ((addr = read_file(*fnp ? fnp : old_filename, second_addr)) < 0)
 673                         return ERR;
 674                 else if (addr && addr != addr_last)
 675                         modified = 1;
 676                 break;
 677         case 's':
 678                 do {
 679                         switch(*ibufp) {
 680                         case '\n':
 681                                 sflags |=SGF;
 682                                 break;
 683                         case 'g':
 684                                 sflags |= SGG;
 685                                 ibufp++;
 686                                 break;
 687                         case 'p':
 688                                 sflags |= SGP;
 689                                 ibufp++;
 690                                 break;
 691                         case 'r':
 692                                 sflags |= SGR;
 693                                 ibufp++;
 694                                 break;
 695                         case '0': case '1': case '2': case '3': case '4':
 696                         case '5': case '6': case '7': case '8': case '9':
 697                                 STRTOL(sgnum, ibufp);
 698                                 sflags |= SGF;
 699                                 sgflag &= ~GSG;         /* override GSG */
 700                                 break;
 701                         default:
 702                                 if (sflags) {
 703                                         errmsg = "invalid command suffix";
 704                                         return ERR;
 705                                 }
 706                         }
 707                 } while (sflags && *ibufp != '\n');
 708                 if (sflags && !pat) {
 709                         errmsg = "no previous substitution";
 710                         return ERR;
 711                 } else if (sflags & SGG)
 712                         sgnum = 0;              /* override numeric arg */
 713                 if (*ibufp != '\n' && *(ibufp + 1) == '\n') {
 714                         errmsg = "invalid pattern delimiter";
 715                         return ERR;
 716                 }
 717                 tpat = pat;
 718                 SPL1();
 719                 if ((!sflags || (sflags & SGR)) &&
 720                     (tpat = get_compiled_pattern()) == NULL) {
 721                         SPL0();
 722                         return ERR;
 723                 } else if (tpat != pat) {
 724                         if (pat) {
 725                                 regfree(pat);
 726                                 free(pat);
 727                         }
 728                         pat = tpat;
 729                         patlock = 1;            /* reserve pattern */
 730                 }
 731                 SPL0();
 732                 if (!sflags && extract_subst_tail(&sgflag, &sgnum) < 0)
 733                         return ERR;
 734                 else if (isglobal)
 735                         sgflag |= GLB;
 736                 else
 737                         sgflag &= ~GLB;
 738                 if (sflags & SGG)
 739                         sgflag ^= GSG;
 740                 if (sflags & SGP)
 741                         sgflag ^= GPR, sgflag &= ~(GLS | GNP);
 742                 do {
 743                         switch(*ibufp) {
 744                         case 'p':
 745                                 sgflag |= GPR, ibufp++;
 746                                 break;
 747                         case 'l':
 748                                 sgflag |= GLS, ibufp++;
 749                                 break;
 750                         case 'n':
 751                                 sgflag |= GNP, ibufp++;
 752                                 break;
 753                         default:
 754                                 n++;
 755                         }
 756                 } while (!n);
 757                 if (check_addr_range(current_addr, current_addr) < 0)
 758                         return ERR;
 759                 GET_COMMAND_SUFFIX();
 760                 if (!isglobal) clear_undo_stack();
 761                 if (search_and_replace(pat, sgflag, sgnum) < 0)
 762                         return ERR;
 763                 break;
 764         case 't':
 765                 if (check_addr_range(current_addr, current_addr) < 0)
 766                         return ERR;
 767                 GET_THIRD_ADDR(addr);
 768                 GET_COMMAND_SUFFIX();
 769                 if (!isglobal) clear_undo_stack();
 770                 if (copy_lines(addr) < 0)
 771                         return ERR;
 772                 break;
 773         case 'u':
 774                 if (addr_cnt > 0) {
 775                         errmsg = "unexpected address";
 776                         return ERR;
 777                 }
 778                 GET_COMMAND_SUFFIX();
 779                 if (pop_undo_stack() < 0)
 780                         return ERR;
 781                 break;
 782         case 'w':
 783         case 'W':
 784                 if ((n = *ibufp) == 'q' || n == 'Q') {
 785                         gflag = EOF;
 786                         ibufp++;
 787                 }
 788                 if (!isspace((unsigned char)*ibufp)) {
 789                         errmsg = "unexpected command suffix";
 790                         return ERR;
 791                 } else if ((fnp = get_filename()) == NULL)
 792                         return ERR;
 793                 if (addr_cnt == 0 && !addr_last)
 794                         first_addr = second_addr = 0;
 795                 else if (check_addr_range(1, addr_last) < 0)
 796                         return ERR;
 797                 GET_COMMAND_SUFFIX();
 798                 if (*old_filename == '\0' && *fnp != '!')
 799                         strcpy(old_filename, fnp);
 800 #ifdef BACKWARDS
 801                 if (*fnp == '\0' && *old_filename == '\0') {
 802                         errmsg = "no current filename";
 803                         return ERR;
 804                 }
 805 #endif
 806                 if ((addr = write_file(*fnp ? fnp : old_filename,
 807                     (c == 'W') ? "a" : "w", first_addr, second_addr)) < 0)
 808                         return ERR;
 809                 else if (addr == addr_last)
 810                         modified = 0;
 811                 else if (modified && !scripted && n == 'q')
 812                         gflag = EMOD;
 813                 break;
 814         case 'x':
 815                 if (addr_cnt > 0) {
 816                         errmsg = "unexpected address";
 817                         return ERR;
 818                 }
 819                 GET_COMMAND_SUFFIX();
 820 #ifdef DES
 821                 des = get_keyword();
 822                 break;
 823 #else
 824                 errmsg = "crypt unavailable";
 825                 return ERR;
 826 #endif
 827         case 'z':
 828 #ifdef BACKWARDS
 829                 if (check_addr_range(first_addr = 1, current_addr + 1) < 0)
 830 #else
 831                 if (check_addr_range(first_addr = 1, current_addr + !isglobal) < 0)
 832 #endif
 833                         return ERR;
 834                 else if ('0' < *ibufp && *ibufp <= '9')
 835                         STRTOL(rows, ibufp);
 836                 GET_COMMAND_SUFFIX();
 837                 if (display_lines(second_addr, min(addr_last,
 838                     second_addr + rows), gflag) < 0)
 839                         return ERR;
 840                 gflag = 0;
 841                 break;
 842         case '=':
 843                 GET_COMMAND_SUFFIX();
 844                 printf("%ld\n", addr_cnt ? second_addr : addr_last);
 845                 break;
 846         case '!':
 847                 if (addr_cnt > 0) {
 848                         errmsg = "unexpected address";
 849                         return ERR;
 850                 } else if ((sflags = get_shell_command()) < 0)
 851                         return ERR;
 852                 GET_COMMAND_SUFFIX();
 853                 if (sflags) printf("%s\n", shcmd + 1);
 854                 system(shcmd + 1);
 855                 if (!scripted) printf("!\n");
 856                 break;
 857         case '\n':
 858 #ifdef BACKWARDS
 859                 if (check_addr_range(first_addr = 1, current_addr + 1) < 0
 860 #else
 861                 if (check_addr_range(first_addr = 1, current_addr + !isglobal) < 0
 862 #endif
 863                  || display_lines(second_addr, second_addr, 0) < 0)
 864                         return ERR;
 865                 break;
 866         default:
 867                 errmsg = "unknown command";
 868                 return ERR;
 869         }
 870         return gflag;
 871 }
 872
 873
 874 /* check_addr_range: return status of address range check */
 875 int
 876 check_addr_range(long n, long m)
 877 {
 878         if (addr_cnt == 0) {
 879                 first_addr = n;
 880                 second_addr = m;
 881         }
 882         if (first_addr > second_addr || 1 > first_addr ||
 883             second_addr > addr_last) {
 884                 errmsg = "invalid address";
 885                 return ERR;
 886         }
 887         return 0;
 888 }
 889
 890
 891 /* get_matching_node_addr: return the address of the next line matching a
 892    pattern in a given direction.  wrap around begin/end of editor buffer if
 893    necessary */
 894 long
 895 get_matching_node_addr(pattern_t *pat, int dir)
 896 {
 897         char *s;
 898         long n = current_addr;
 899         line_t *lp;
 900
 901         if (!pat) return ERR;
 902         do {
 903                if ((n = dir ? INC_MOD(n, addr_last) : DEC_MOD(n, addr_last))) {
 904                         lp = get_addressed_line_node(n);
 905                         if ((s = get_sbuf_line(lp)) == NULL)
 906                                 return ERR;
 907                         if (isbinary)
 908                                 NUL_TO_NEWLINE(s, lp->len);
 909                         if (!regexec(pat, s, 0, NULL, 0))
 910                                 return n;
 911                }
 912         } while (n != current_addr);
 913         errmsg = "no match";
 914         return  ERR;
 915 }
 916
 917
 918 /* get_filename: return pointer to copy of filename in the command buffer */
 919 char *
 920 get_filename(void)
 921 {
 922         static char *file = NULL;
 923         static int filesz = 0;
 924
 925         int n;
 926
 927         if (*ibufp != '\n') {
 928                 SKIP_BLANKS();
 929                 if (*ibufp == '\n') {
 930                         errmsg = "invalid filename";
 931                         return NULL;
 932                 } else if ((ibufp = get_extended_line(&n, 1)) == NULL)
 933                         return NULL;
 934                 else if (*ibufp == '!') {
 935                         ibufp++;
 936                         if ((n = get_shell_command()) < 0)
 937                                 return NULL;
 938                         if (n)
 939                                 printf("%s\n", shcmd + 1);
 940                         return shcmd;
 941                 } else if (n > PATH_MAX - 1) {
 942                         errmsg = "filename too long";
 943                         return  NULL;
 944                 }
 945         }
 946 #ifndef BACKWARDS
 947         else if (*old_filename == '\0') {
 948                 errmsg = "no current filename";
 949                 return  NULL;
 950         }
 951 #endif
 952         REALLOC(file, filesz, PATH_MAX, NULL);
 953         for (n = 0; *ibufp != '\n';)
 954                 file[n++] = *ibufp++;
 955         file[n] = '\0';
 956         return is_legal_filename(file) ? file : NULL;
 957 }
 958
 959
 960 /* get_shell_command: read a shell command from stdin; return substitution
 961    status */
 962 int
 963 get_shell_command(void)
 964 {
 965         static char *buf = NULL;
 966         static int n = 0;
 967
 968         char *s;                        /* substitution char pointer */
 969         int i = 0;
 970         int j = 0;
 971
 972         if (red) {
 973                 errmsg = "shell access restricted";
 974                 return ERR;
 975         } else if ((s = ibufp = get_extended_line(&j, 1)) == NULL)
 976                 return ERR;
 977         REALLOC(buf, n, j + 1, ERR);
 978         buf[i++] = '!';                 /* prefix command w/ bang */
 979         while (*ibufp != '\n')
 980                 switch (*ibufp) {
 981                 default:
 982                         REALLOC(buf, n, i + 2, ERR);
 983                         buf[i++] = *ibufp;
 984                         if (*ibufp++ == '\\')
 985                                 buf[i++] = *ibufp++;
 986                         break;
 987                 case '!':
 988                         if (s != ibufp) {
 989                                 REALLOC(buf, n, i + 1, ERR);
 990                                 buf[i++] = *ibufp++;
 991                         }
 992 #ifdef BACKWARDS
 993                         else if (shcmd == NULL || *(shcmd + 1) == '\0')
 994 #else
 995                         else if (shcmd == NULL)
 996 #endif
 997                         {
 998                                 errmsg = "no previous command";
 999                                 return ERR;
1000                         } else {
1001                                 REALLOC(buf, n, i + shcmdi, ERR);
1002                                 for (s = shcmd + 1; s < shcmd + shcmdi;)
1003                                         buf[i++] = *s++;
1004                                 s = ibufp++;
1005                         }
1006                         break;
1007                 case '%':
1008                         if (*old_filename  == '\0') {
1009                                 errmsg = "no current filename";
1010                                 return ERR;
1011                         }
1012                         j = strlen(s = strip_escapes(old_filename));
1013                         REALLOC(buf, n, i + j, ERR);
1014                         while (j--)
1015                                 buf[i++] = *s++;
1016                         s = ibufp++;
1017                         break;
1018                 }
1019         REALLOC(shcmd, shcmdsz, i + 1, ERR);
1020         memcpy(shcmd, buf, i);
1021         shcmd[shcmdi = i] = '\0';
1022         return *s == '!' || *s == '%';
1023 }
1024
1025
1026 /* append_lines: insert text from stdin to after line n; stop when either a
1027    single period is read or EOF; return status */
1028 int
1029 append_lines(long n)
1030 {
1031         int l;
1032         const char *lp = ibuf;
1033         const char *eot;
1034         undo_t *up = NULL;
1035
1036         for (current_addr = n;;) {
1037                 if (!isglobal) {
1038                         if ((l = get_tty_line()) < 0)
1039                                 return ERR;
1040                         else if (l == 0 || ibuf[l - 1] != '\n') {
1041                                 clearerr(stdin);
1042                                 return  l ? EOF : 0;
1043                         }
1044                         lp = ibuf;
1045                 } else if (*(lp = ibufp) == '\0')
1046                         return 0;
1047                 else {
1048                         while (*ibufp++ != '\n')
1049                                 ;
1050                         l = ibufp - lp;
1051                 }
1052                 if (l == 2 && lp[0] == '.' && lp[1] == '\n') {
1053                         return 0;
1054                 }
1055                 eot = lp + l;
1056                 SPL1();
1057                 do {
1058                         if ((lp = put_sbuf_line(lp)) == NULL) {
1059                                 SPL0();
1060                                 return ERR;
1061                         } else if (up)
1062                                 up->t = get_addressed_line_node(current_addr);
1063                         else if ((up = push_undo_stack(UADD, current_addr,
1064                             current_addr)) == NULL) {
1065                                 SPL0();
1066                                 return ERR;
1067                         }
1068                 } while (lp != eot);
1069                 modified = 1;
1070                 SPL0();
1071         }
1072         /* NOTREACHED */
1073 }
1074
1075
1076 /* join_lines: replace a range of lines with the joined text of those lines */
1077 int
1078 join_lines(long from, long to)
1079 {
1080         static char *buf = NULL;
1081         static int n;
1082
1083         char *s;
1084         int size = 0;
1085         line_t *bp, *ep;
1086
1087         ep = get_addressed_line_node(INC_MOD(to, addr_last));
1088         bp = get_addressed_line_node(from);
1089         for (; bp != ep; bp = bp->q_forw) {
1090                 if ((s = get_sbuf_line(bp)) == NULL)
1091                         return ERR;
1092                 REALLOC(buf, n, size + bp->len, ERR);
1093                 memcpy(buf + size, s, bp->len);
1094                 size += bp->len;
1095         }
1096         REALLOC(buf, n, size + 2, ERR);
1097         memcpy(buf + size, "\n", 2);
1098         if (delete_lines(from, to) < 0)
1099                 return ERR;
1100         current_addr = from - 1;
1101         SPL1();
1102         if (put_sbuf_line(buf) == NULL ||
1103             push_undo_stack(UADD, current_addr, current_addr) == NULL) {
1104                 SPL0();
1105                 return ERR;
1106         }
1107         modified = 1;
1108         SPL0();
1109         return 0;
1110 }
1111
1112
1113 /* move_lines: move a range of lines */
1114 int
1115 move_lines(long addr)
1116 {
1117         line_t *b1, *a1, *b2, *a2;
1118         long n = INC_MOD(second_addr, addr_last);
1119         long p = first_addr - 1;
1120         int done = (addr == first_addr - 1 || addr == second_addr);
1121
1122         SPL1();
1123         if (done) {
1124                 a2 = get_addressed_line_node(n);
1125                 b2 = get_addressed_line_node(p);
1126                 current_addr = second_addr;
1127         } else if (push_undo_stack(UMOV, p, n) == NULL ||
1128             push_undo_stack(UMOV, addr, INC_MOD(addr, addr_last)) == NULL) {
1129                 SPL0();
1130                 return ERR;
1131         } else {
1132                 a1 = get_addressed_line_node(n);
1133                 if (addr < first_addr) {
1134                         b1 = get_addressed_line_node(p);
1135                         b2 = get_addressed_line_node(addr);
1136                                         /* this get_addressed_line_node last! */
1137                 } else {
1138                         b2 = get_addressed_line_node(addr);
1139                         b1 = get_addressed_line_node(p);
1140                                         /* this get_addressed_line_node last! */
1141                 }
1142                 a2 = b2->q_forw;
1143                 REQUE(b2, b1->q_forw);
1144                 REQUE(a1->q_back, a2);
1145                 REQUE(b1, a1);
1146                 current_addr = addr + ((addr < first_addr) ?
1147                     second_addr - first_addr + 1 : 0);
1148         }
1149         if (isglobal)
1150                 unset_active_nodes(b2->q_forw, a2);
1151         modified = 1;
1152         SPL0();
1153         return 0;
1154 }
1155
1156
1157 /* copy_lines: copy a range of lines; return status */
1158 int
1159 copy_lines(long addr)
1160 {
1161         line_t *lp, *np = get_addressed_line_node(first_addr);
1162         undo_t *up = NULL;
1163         long n = second_addr - first_addr + 1;
1164         long m = 0;
1165
1166         current_addr = addr;
1167         if (first_addr <= addr && addr < second_addr) {
1168                 n =  addr - first_addr + 1;
1169                 m = second_addr - addr;
1170         }
1171         for (; n > 0; n=m, m=0, np = get_addressed_line_node(current_addr + 1))
1172                 for (; n-- > 0; np = np->q_forw) {
1173                         SPL1();
1174                         if ((lp = dup_line_node(np)) == NULL) {
1175                                 SPL0();
1176                                 return ERR;
1177                         }
1178                         add_line_node(lp);
1179                         if (up)
1180                                 up->t = lp;
1181                         else if ((up = push_undo_stack(UADD, current_addr,
1182                             current_addr)) == NULL) {
1183                                 SPL0();
1184                                 return ERR;
1185                         }
1186                         modified = 1;
1187                         SPL0();
1188                 }
1189         return 0;
1190 }
1191
1192
1193 /* delete_lines: delete a range of lines */
1194 int
1195 delete_lines(long from, long to)
1196 {
1197         line_t *n, *p;
1198
1199         SPL1();
1200         if (push_undo_stack(UDEL, from, to) == NULL) {
1201                 SPL0();
1202                 return ERR;
1203         }
1204         n = get_addressed_line_node(INC_MOD(to, addr_last));
1205         p = get_addressed_line_node(from - 1);
1206                                         /* this get_addressed_line_node last! */
1207         if (isglobal)
1208                 unset_active_nodes(p->q_forw, n);
1209         REQUE(p, n);
1210         addr_last -= to - from + 1;
1211         current_addr = from - 1;
1212         modified = 1;
1213         SPL0();
1214         return 0;
1215 }
1216
1217
1218 /* display_lines: print a range of lines to stdout */
1219 int
1220 display_lines(long from, long to, int gflag)
1221 {
1222         line_t *bp;
1223         line_t *ep;
1224         char *s;
1225
1226         if (!from) {
1227                 errmsg = "invalid address";
1228                 return ERR;
1229         }
1230         ep = get_addressed_line_node(INC_MOD(to, addr_last));
1231         bp = get_addressed_line_node(from);
1232         for (; bp != ep; bp = bp->q_forw) {
1233                 if ((s = get_sbuf_line(bp)) == NULL)
1234                         return ERR;
1235                 if (put_tty_line(s, bp->len, current_addr = from++, gflag) < 0)
1236                         return ERR;
1237         }
1238         return 0;
1239 }
1240
1241
1242 #define MAXMARK 26                      /* max number of marks */
1243
1244 line_t  *mark[MAXMARK];                 /* line markers */
1245 int markno;                             /* line marker count */
1246
1247 /* mark_line_node: set a line node mark */
1248 int
1249 mark_line_node(line_t *lp, int n)
1250 {
1251         if (!islower((unsigned char)n)) {
1252                 errmsg = "invalid mark character";
1253                 return ERR;
1254         } else if (mark[n - 'a'] == NULL)
1255                 markno++;
1256         mark[n - 'a'] = lp;
1257         return 0;
1258 }
1259
1260
1261 /* get_marked_node_addr: return address of a marked line */
1262 long
1263 get_marked_node_addr(int n)
1264 {
1265         if (!islower((unsigned char)n)) {
1266                 errmsg = "invalid mark character";
1267                 return ERR;
1268         }
1269         return get_line_node_addr(mark[n - 'a']);
1270 }
1271
1272
1273 /* unmark_line_node: clear line node mark */
1274 void
1275 unmark_line_node(line_t *lp)
1276 {
1277         int i;
1278
1279         for (i = 0; markno && i < MAXMARK; i++)
1280                 if (mark[i] == lp) {
1281                         mark[i] = NULL;
1282                         markno--;
1283                 }
1284 }
1285
1286
1287 /* dup_line_node: return a pointer to a copy of a line node */
1288 line_t *
1289 dup_line_node(line_t *lp)
1290 {
1291         line_t *np;
1292
1293         if ((np = (line_t *) malloc(sizeof(line_t))) == NULL) {
1294                 fprintf(stderr, "%s\n", strerror(errno));
1295                 errmsg = "out of memory";
1296                 return NULL;
1297         }
1298         np->seek = lp->seek;
1299         np->len = lp->len;
1300         return np;
1301 }
1302
1303
1304 /* has_trailing_escape:  return the parity of escapes preceding a character
1305    in a string */
1306 int
1307 has_trailing_escape(char *s, char *t)
1308 {
1309     return (s == t || *(t - 1) != '\\') ? 0 : !has_trailing_escape(s, t - 1);
1310 }
1311
1312
1313 /* strip_escapes: return copy of escaped string of at most length PATH_MAX */
1314 char *
1315 strip_escapes(char *s)
1316 {
1317         static char *file = NULL;
1318         static int filesz = 0;
1319
1320         int i = 0;
1321
1322         REALLOC(file, filesz, PATH_MAX, NULL);
1323         while (i < filesz - 1   /* Worry about a possible trailing escape */
1324                && (file[i++] = (*s == '\\') ? *++s : *s))
1325                 s++;
1326         return file;
1327 }
1328
1329
1330 void
1331 signal_hup(int signo)
1332 {
1333         if (mutex)
1334                 sigflags |= (1 << (signo - 1));
1335         else
1336                 handle_hup(signo);
1337 }
1338
1339
1340 void
1341 signal_int(int signo)
1342 {
1343         if (mutex)
1344                 sigflags |= (1 << (signo - 1));
1345         else
1346                 handle_int(signo);
1347 }
1348
1349
1350 void
1351 handle_hup(int signo)
1352 {
1353         char *hup = NULL;               /* hup filename */
1354         char *s;
1355         char ed_hup[] = "ed.hup";
1356         int n;
1357
1358         if (!sigactive)
1359                 quit(1);
1360         sigflags &= ~(1 << (signo - 1));
1361         if (addr_last && write_file(ed_hup, "w", 1, addr_last) < 0 &&
1362             (s = getenv("HOME")) != NULL &&
1363             (n = strlen(s)) + 8 <= PATH_MAX &&  /* "ed.hup" + '/' */
1364             (hup = (char *) malloc(n + 10)) != NULL) {
1365                 strcpy(hup, s);
1366                 if (hup[n - 1] != '/')
1367                         hup[n] = '/', hup[n+1] = '\0';
1368                 strcat(hup, "ed.hup");
1369                 write_file(hup, "w", 1, addr_last);
1370         }
1371         quit(2);
1372 }
1373
1374
1375 void
1376 handle_int(int signo)
1377 {
1378         if (!sigactive)
1379                 quit(1);
1380         sigflags &= ~(1 << (signo - 1));
1381 #ifdef _POSIX_SOURCE
1382         siglongjmp(env, -1);
1383 #else
1384         longjmp(env, -1);
1385 #endif
1386 }
1387
1388
1389 int cols = 72;                          /* wrap column */
1390
1391 void
1392 handle_winch(int signo)
1393 {
1394         int save_errno = errno;
1395
1396         struct winsize ws;              /* window size structure */
1397
1398         sigflags &= ~(1 << (signo - 1));
1399         if (ioctl(0, TIOCGWINSZ, (char *) &ws) >= 0) {
1400                 if (ws.ws_row > 2) rows = ws.ws_row - 2;
1401                 if (ws.ws_col > 8) cols = ws.ws_col - 8;
1402         }
1403         errno = save_errno;
1404 }
1405
1406
1407 /* is_legal_filename: return a legal filename */
1408 int
1409 is_legal_filename(char *s)
1410 {
1411         if (red && (*s == '!' || !strcmp(s, "..") || strchr(s, '/'))) {
1412                 errmsg = "shell access restricted";
1413                 return 0;
1414         }
1415         return 1;
1416 }