contrib/less/command.c

   1 /*
   2  * Copyright (C) 1984-2011  Mark Nudelman
   3  *
   4  * You may distribute under the terms of either the GNU General Public
   5  * License or the Less License, as specified in the README file.
   6  *
   7  * For more information about less, or for information on how to
   8  * contact the author, see the README file.
   9  */
  10
  11
  12 /*
  13  * User-level command processor.
  14  */
  15
  16 #include "less.h"
  17 #if MSDOS_COMPILER==WIN32C
  18 #include <windows.h>
  19 #endif
  20 #include "position.h"
  21 #include "option.h"
  22 #include "cmd.h"
  23
  24 extern int erase_char, erase2_char, kill_char;
  25 extern int sigs;
  26 extern int quit_if_one_screen;
  27 extern int squished;
  28 extern int sc_width;
  29 extern int sc_height;
  30 extern int swindow;
  31 extern int jump_sline;
  32 extern int quitting;
  33 extern int wscroll;
  34 extern int top_scroll;
  35 extern int ignore_eoi;
  36 extern int secure;
  37 extern int hshift;
  38 extern int show_attn;
  39 extern char *every_first_cmd;
  40 extern char *curr_altfilename;
  41 extern char version[];
  42 extern struct scrpos initial_scrpos;
  43 extern IFILE curr_ifile;
  44 extern void constant *ml_search;
  45 extern void constant *ml_examine;
  46 #if SHELL_ESCAPE || PIPEC
  47 extern void constant *ml_shell;
  48 #endif
  49 #if EDITOR
  50 extern char *editor;
  51 extern char *editproto;
  52 #endif
  53 extern int screen_trashed;      /* The screen has been overwritten */
  54 extern int shift_count;
  55 extern int oldbot;
  56 extern int forw_prompt;
  57
  58 #if SHELL_ESCAPE
  59 static char *shellcmd = NULL;   /* For holding last shell command for "!!" */
  60 #endif
  61 static int mca;                 /* The multicharacter command (action) */
  62 static int search_type;         /* The previous type of search */
  63 static LINENUM number;          /* The number typed by the user */
  64 static long fraction;           /* The fractional part of the number */
  65 static struct loption *curropt;
  66 static int opt_lower;
  67 static int optflag;
  68 static int optgetname;
  69 static POSITION bottompos;
  70 static int save_hshift;
  71 #if PIPEC
  72 static char pipec;
  73 #endif
  74
  75 struct ungot {
  76         struct ungot *ug_next;
  77         char ug_char;
  78 };
  79 static struct ungot* ungot = NULL;
  80 static int unget_end = 0;
  81
  82 static void multi_search();
  83
  84 /*
  85  * Move the cursor to start of prompt line before executing a command.
  86  * This looks nicer if the command takes a long time before
  87  * updating the screen.
  88  */
  89         static void
  90 cmd_exec()
  91 {
  92 #if HILITE_SEARCH
  93         clear_attn();
  94 #endif
  95         clear_bot();
  96         flush();
  97 }
  98
  99 /*
 100  * Set up the display to start a new multi-character command.
 101  */
 102         static void
 103 start_mca(action, prompt, mlist, cmdflags)
 104         int action;
 105         char *prompt;
 106         void *mlist;
 107         int cmdflags;
 108 {
 109         mca = action;
 110         clear_bot();
 111         clear_cmd();
 112         cmd_putstr(prompt);
 113         set_mlist(mlist, cmdflags);
 114 }
 115
 116         public int
 117 in_mca()
 118 {
 119         return (mca != 0 && mca != A_PREFIX);
 120 }
 121
 122 /*
 123  * Set up the display to start a new search command.
 124  */
 125         static void
 126 mca_search()
 127 {
 128 #if HILITE_SEARCH
 129         if (search_type & SRCH_FILTER)
 130                 mca = A_FILTER;
 131         else
 132 #endif
 133         if (search_type & SRCH_FORW)
 134                 mca = A_F_SEARCH;
 135         else
 136                 mca = A_B_SEARCH;
 137
 138         clear_bot();
 139         clear_cmd();
 140
 141         if (search_type & SRCH_NO_MATCH)
 142                 cmd_putstr("Non-match ");
 143         if (search_type & SRCH_FIRST_FILE)
 144                 cmd_putstr("First-file ");
 145         if (search_type & SRCH_PAST_EOF)
 146                 cmd_putstr("EOF-ignore ");
 147         if (search_type & SRCH_NO_MOVE)
 148                 cmd_putstr("Keep-pos ");
 149         if (search_type & SRCH_NO_REGEX)
 150                 cmd_putstr("Regex-off ");
 151
 152 #if HILITE_SEARCH
 153         if (search_type & SRCH_FILTER)
 154                 cmd_putstr("&/");
 155         else
 156 #endif
 157         if (search_type & SRCH_FORW)
 158                 cmd_putstr("/");
 159         else
 160                 cmd_putstr("?");
 161         set_mlist(ml_search, 0);
 162 }
 163
 164 /*
 165  * Set up the display to start a new toggle-option command.
 166  */
 167         static void
 168 mca_opt_toggle()
 169 {
 170         int no_prompt;
 171         int flag;
 172         char *dash;
 173
 174         no_prompt = (optflag & OPT_NO_PROMPT);
 175         flag = (optflag & ~OPT_NO_PROMPT);
 176         dash = (flag == OPT_NO_TOGGLE) ? "_" : "-";
 177
 178         mca = A_OPT_TOGGLE;
 179         clear_bot();
 180         clear_cmd();
 181         cmd_putstr(dash);
 182         if (optgetname)
 183                 cmd_putstr(dash);
 184         if (no_prompt)
 185                 cmd_putstr("(P)");
 186         switch (flag)
 187         {
 188         case OPT_UNSET:
 189                 cmd_putstr("+");
 190                 break;
 191         case OPT_SET:
 192                 cmd_putstr("!");
 193                 break;
 194         }
 195         set_mlist(NULL, 0);
 196 }
 197
 198 /*
 199  * Execute a multicharacter command.
 200  */
 201         static void
 202 exec_mca()
 203 {
 204         register char *cbuf;
 205
 206         cmd_exec();
 207         cbuf = get_cmdbuf();
 208
 209         switch (mca)
 210         {
 211         case A_F_SEARCH:
 212         case A_B_SEARCH:
 213                 multi_search(cbuf, (int) number);
 214                 break;
 215 #if HILITE_SEARCH
 216         case A_FILTER:
 217                 search_type ^= SRCH_NO_MATCH;
 218                 set_filter_pattern(cbuf, search_type);
 219                 break;
 220 #endif
 221         case A_FIRSTCMD:
 222                 /*
 223                  * Skip leading spaces or + signs in the string.
 224                  */
 225                 while (*cbuf == '+' || *cbuf == ' ')
 226                         cbuf++;
 227                 if (every_first_cmd != NULL)
 228                         free(every_first_cmd);
 229                 if (*cbuf == '\0')
 230                         every_first_cmd = NULL;
 231                 else
 232                         every_first_cmd = save(cbuf);
 233                 break;
 234         case A_OPT_TOGGLE:
 235                 toggle_option(curropt, opt_lower, cbuf, optflag);
 236                 curropt = NULL;
 237                 break;
 238         case A_F_BRACKET:
 239                 match_brac(cbuf[0], cbuf[1], 1, (int) number);
 240                 break;
 241         case A_B_BRACKET:
 242                 match_brac(cbuf[1], cbuf[0], 0, (int) number);
 243                 break;
 244 #if EXAMINE
 245         case A_EXAMINE:
 246                 if (secure)
 247                         break;
 248                 edit_list(cbuf);
 249 #if TAGS
 250                 /* If tag structure is loaded then clean it up. */
 251                 cleantags();
 252 #endif
 253                 break;
 254 #endif
 255 #if SHELL_ESCAPE
 256         case A_SHELL:
 257                 /*
 258                  * !! just uses whatever is in shellcmd.
 259                  * Otherwise, copy cmdbuf to shellcmd,
 260                  * expanding any special characters ("%" or "#").
 261                  */
 262                 if (*cbuf != '!')
 263                 {
 264                         if (shellcmd != NULL)
 265                                 free(shellcmd);
 266                         shellcmd = fexpand(cbuf);
 267                 }
 268
 269                 if (secure)
 270                         break;
 271                 if (shellcmd == NULL)
 272                         lsystem("", "!done");
 273                 else
 274                         lsystem(shellcmd, "!done");
 275                 break;
 276 #endif
 277 #if PIPEC
 278         case A_PIPE:
 279                 if (secure)
 280                         break;
 281                 (void) pipe_mark(pipec, cbuf);
 282                 error("|done", NULL_PARG);
 283                 break;
 284 #endif
 285         }
 286 }
 287
 288 /*
 289  * Is a character an erase or kill char?
 290  */
 291         static int
 292 is_erase_char(c)
 293         int c;
 294 {
 295         return (c == erase_char || c == erase2_char || c == kill_char);
 296 }
 297
 298 /*
 299  * Handle the first char of an option (after the initial dash).
 300  */
 301         static int
 302 mca_opt_first_char(c)
 303     int c;
 304 {
 305         int flag = (optflag & ~OPT_NO_PROMPT);
 306         if (flag == OPT_NO_TOGGLE)
 307         {
 308                 switch (c)
 309                 {
 310                 case '_':
 311                         /* "__" = long option name. */
 312                         optgetname = TRUE;
 313                         mca_opt_toggle();
 314                         return (MCA_MORE);
 315                 }
 316         } else
 317         {
 318                 switch (c)
 319                 {
 320                 case '+':
 321                         /* "-+" = UNSET. */
 322                         optflag = (flag == OPT_UNSET) ?
 323                                 OPT_TOGGLE : OPT_UNSET;
 324                         mca_opt_toggle();
 325                         return (MCA_MORE);
 326                 case '!':
 327                         /* "-!" = SET */
 328                         optflag = (flag == OPT_SET) ?
 329                                 OPT_TOGGLE : OPT_SET;
 330                         mca_opt_toggle();
 331                         return (MCA_MORE);
 332                 case CONTROL('P'):
 333                         optflag ^= OPT_NO_PROMPT;
 334                         mca_opt_toggle();
 335                         return (MCA_MORE);
 336                 case '-':
 337                         /* "--" = long option name. */
 338                         optgetname = TRUE;
 339                         mca_opt_toggle();
 340                         return (MCA_MORE);
 341                 }
 342         }
 343         /* Char was not handled here. */
 344         return (NO_MCA);
 345 }
 346
 347 /*
 348  * Add a char to a long option name.
 349  * See if we've got a match for an option name yet.
 350  * If so, display the complete name and stop
 351  * accepting chars until user hits RETURN.
 352  */
 353         static int
 354 mca_opt_nonfirst_char(c)
 355         int c;
 356 {
 357         char *p;
 358         char *oname;
 359
 360         if (curropt != NULL)
 361         {
 362                 /*
 363                  * Already have a match for the name.
 364                  * Don't accept anything but erase/kill.
 365                  */
 366                 if (is_erase_char(c))
 367                         return (MCA_DONE);
 368                 return (MCA_MORE);
 369         }
 370         /*
 371          * Add char to cmd buffer and try to match
 372          * the option name.
 373          */
 374         if (cmd_char(c) == CC_QUIT)
 375                 return (MCA_DONE);
 376         p = get_cmdbuf();
 377         opt_lower = ASCII_IS_LOWER(p[0]);
 378         curropt = findopt_name(&p, &oname, NULL);
 379         if (curropt != NULL)
 380         {
 381                 /*
 382                  * Got a match.
 383                  * Remember the option and
 384                  * display the full option name.
 385                  */
 386                 cmd_reset();
 387                 mca_opt_toggle();
 388                 for (p = oname;  *p != '\0';  p++)
 389                 {
 390                         c = *p;
 391                         if (!opt_lower && ASCII_IS_LOWER(c))
 392                                 c = ASCII_TO_UPPER(c);
 393                         if (cmd_char(c) != CC_OK)
 394                                 return (MCA_DONE);
 395                 }
 396         }
 397         return (MCA_MORE);
 398 }
 399
 400 /*
 401  * Handle a char of an option toggle command.
 402  */
 403         static int
 404 mca_opt_char(c)
 405         int c;
 406 {
 407         PARG parg;
 408
 409         /*
 410          * This may be a short option (single char),
 411          * or one char of a long option name,
 412          * or one char of the option parameter.
 413          */
 414         if (curropt == NULL && len_cmdbuf() == 0)
 415         {
 416                 int ret = mca_opt_first_char(c);
 417                 if (ret != NO_MCA)
 418                         return (ret);
 419         }
 420         if (optgetname)
 421         {
 422                 /* We're getting a long option name.  */
 423                 if (c != '\n' && c != '\r')
 424                         return (mca_opt_nonfirst_char(c));
 425                 if (curropt == NULL)
 426                 {
 427                         parg.p_string = get_cmdbuf();
 428                         error("There is no --%s option", &parg);
 429                         return (MCA_DONE);
 430                 }
 431                 optgetname = FALSE;
 432                 cmd_reset();
 433         } else
 434         {
 435                 if (is_erase_char(c))
 436                         return (NO_MCA);
 437                 if (curropt != NULL)
 438                         /* We're getting the option parameter. */
 439                         return (NO_MCA);
 440                 curropt = findopt(c);
 441                 if (curropt == NULL)
 442                 {
 443                         parg.p_string = propt(c);
 444                         error("There is no %s option", &parg);
 445                         return (MCA_DONE);
 446                 }
 447         }
 448         /*
 449          * If the option which was entered does not take a
 450          * parameter, toggle the option immediately,
 451          * so user doesn't have to hit RETURN.
 452          */
 453         if ((optflag & ~OPT_NO_PROMPT) != OPT_TOGGLE ||
 454             !opt_has_param(curropt))
 455         {
 456                 toggle_option(curropt, ASCII_IS_LOWER(c), "", optflag);
 457                 return (MCA_DONE);
 458         }
 459         /*
 460          * Display a prompt appropriate for the option parameter.
 461          */
 462         start_mca(A_OPT_TOGGLE, opt_prompt(curropt), (void*)NULL, 0);
 463         return (MCA_MORE);
 464 }
 465
 466 /*
 467  * Handle a char of a search command.
 468  */
 469         static int
 470 mca_search_char(c)
 471         int c;
 472 {
 473         int flag = 0;
 474
 475         /*
 476          * Certain characters as the first char of
 477          * the pattern have special meaning:
 478          *      !  Toggle the NO_MATCH flag
 479          *      *  Toggle the PAST_EOF flag
 480          *      @  Toggle the FIRST_FILE flag
 481          */
 482         if (len_cmdbuf() > 0)
 483                 return (NO_MCA);
 484
 485         switch (c)
 486         {
 487         case CONTROL('E'): /* ignore END of file */
 488         case '*':
 489                 if (mca != A_FILTER)
 490                         flag = SRCH_PAST_EOF;
 491                 break;
 492         case CONTROL('F'): /* FIRST file */
 493         case '@':
 494                 if (mca != A_FILTER)
 495                         flag = SRCH_FIRST_FILE;
 496                 break;
 497         case CONTROL('K'): /* KEEP position */
 498                 if (mca != A_FILTER)
 499                         flag = SRCH_NO_MOVE;
 500                 break;
 501         case CONTROL('R'): /* Don't use REGULAR EXPRESSIONS */
 502                 flag = SRCH_NO_REGEX;
 503                 break;
 504         case CONTROL('N'): /* NOT match */
 505         case '!':
 506                 flag = SRCH_NO_MATCH;
 507                 break;
 508         }
 509
 510         if (flag != 0)
 511         {
 512                 search_type ^= flag;
 513                 mca_search();
 514                 return (MCA_MORE);
 515         }
 516         return (NO_MCA);
 517 }
 518
 519 /*
 520  * Handle a character of a multi-character command.
 521  */
 522         static int
 523 mca_char(c)
 524         int c;
 525 {
 526         int ret;
 527
 528         switch (mca)
 529         {
 530         case 0:
 531                 /*
 532                  * We're not in a multicharacter command.
 533                  */
 534                 return (NO_MCA);
 535
 536         case A_PREFIX:
 537                 /*
 538                  * In the prefix of a command.
 539                  * This not considered a multichar command
 540                  * (even tho it uses cmdbuf, etc.).
 541                  * It is handled in the commands() switch.
 542                  */
 543                 return (NO_MCA);
 544
 545         case A_DIGIT:
 546                 /*
 547                  * Entering digits of a number.
 548                  * Terminated by a non-digit.
 549                  */
 550                 if (!((c >= '0' && c <= '9') || c == '.') &&
 551                   editchar(c, EC_PEEK|EC_NOHISTORY|EC_NOCOMPLETE|EC_NORIGHTLEFT) == A_INVALID)
 552                 {
 553                         /*
 554                          * Not part of the number.
 555                          * End the number and treat this char
 556                          * as a normal command character.
 557                          */
 558                         number = cmd_int(&fraction);
 559                         mca = 0;
 560                         cmd_accept();
 561                         return (NO_MCA);
 562                 }
 563                 break;
 564
 565         case A_OPT_TOGGLE:
 566                 ret = mca_opt_char(c);
 567                 if (ret != NO_MCA)
 568                         return (ret);
 569                 break;
 570
 571         case A_F_SEARCH:
 572         case A_B_SEARCH:
 573         case A_FILTER:
 574                 ret = mca_search_char(c);
 575                 if (ret != NO_MCA)
 576                         return (ret);
 577                 break;
 578
 579         default:
 580                 /* Other multicharacter command. */
 581                 break;
 582         }
 583
 584         /*
 585          * The multichar command is terminated by a newline.
 586          */
 587         if (c == '\n' || c == '\r')
 588         {
 589                 /*
 590                  * Execute the command.
 591                  */
 592                 exec_mca();
 593                 return (MCA_DONE);
 594         }
 595
 596         /*
 597          * Append the char to the command buffer.
 598          */
 599         if (cmd_char(c) == CC_QUIT)
 600                 /*
 601                  * Abort the multi-char command.
 602                  */
 603                 return (MCA_DONE);
 604
 605         if ((mca == A_F_BRACKET || mca == A_B_BRACKET) && len_cmdbuf() >= 2)
 606         {
 607                 /*
 608                  * Special case for the bracket-matching commands.
 609                  * Execute the command after getting exactly two
 610                  * characters from the user.
 611                  */
 612                 exec_mca();
 613                 return (MCA_DONE);
 614         }
 615
 616         /*
 617          * Need another character.
 618          */
 619         return (MCA_MORE);
 620 }
 621
 622 /*
 623  * Discard any buffered file data.
 624  */
 625         static void
 626 clear_buffers()
 627 {
 628         if (!(ch_getflags() & CH_CANSEEK))
 629                 return;
 630         ch_flush();
 631         clr_linenum();
 632 #if HILITE_SEARCH
 633         clr_hilite();
 634 #endif
 635 }
 636
 637 /*
 638  * Make sure the screen is displayed.
 639  */
 640         static void
 641 make_display()
 642 {
 643         /*
 644          * If nothing is displayed yet, display starting from initial_scrpos.
 645          */
 646         if (empty_screen())
 647         {
 648                 if (initial_scrpos.pos == NULL_POSITION)
 649                         /*
 650                          * {{ Maybe this should be:
 651                          *    jump_loc(ch_zero(), jump_sline);
 652                          *    but this behavior seems rather unexpected
 653                          *    on the first screen. }}
 654                          */
 655                         jump_loc(ch_zero(), 1);
 656                 else
 657                         jump_loc(initial_scrpos.pos, initial_scrpos.ln);
 658         } else if (screen_trashed)
 659         {
 660                 int save_top_scroll = top_scroll;
 661                 int save_ignore_eoi = ignore_eoi;
 662                 top_scroll = 1;
 663                 ignore_eoi = 0;
 664                 if (screen_trashed == 2)
 665                 {
 666                         /* Special case used by ignore_eoi: re-open the input file
 667                          * and jump to the end of the file. */
 668                         reopen_curr_ifile();
 669                         jump_forw();
 670                 }
 671                 repaint();
 672                 top_scroll = save_top_scroll;
 673                 ignore_eoi = save_ignore_eoi;
 674         }
 675 }
 676
 677 /*
 678  * Display the appropriate prompt.
 679  */
 680         static void
 681 prompt()
 682 {
 683         register char *p;
 684
 685         if (ungot != NULL)
 686         {
 687                 /*
 688                  * No prompt necessary if commands are from
 689                  * ungotten chars rather than from the user.
 690                  */
 691                 return;
 692         }
 693
 694         /*
 695          * Make sure the screen is displayed.
 696          */
 697         make_display();
 698         bottompos = position(BOTTOM_PLUS_ONE);
 699
 700         /*
 701          * If we've hit EOF on the last file and the -E flag is set, quit.
 702          */
 703         if (get_quit_at_eof() == OPT_ONPLUS &&
 704             eof_displayed() && !(ch_getflags() & CH_HELPFILE) &&
 705             next_ifile(curr_ifile) == NULL_IFILE)
 706                 quit(QUIT_OK);
 707
 708         /*
 709          * If the entire file is displayed and the -F flag is set, quit.
 710          */
 711         if (quit_if_one_screen &&
 712             entire_file_displayed() && !(ch_getflags() & CH_HELPFILE) &&
 713             next_ifile(curr_ifile) == NULL_IFILE)
 714                 quit(QUIT_OK);
 715
 716 #if MSDOS_COMPILER==WIN32C
 717         /*
 718          * In Win32, display the file name in the window title.
 719          */
 720         if (!(ch_getflags() & CH_HELPFILE))
 721                 SetConsoleTitle(pr_expand("Less?f - %f.", 0));
 722 #endif
 723         /*
 724          * Select the proper prompt and display it.
 725          */
 726         /*
 727          * If the previous action was a forward movement,
 728          * don't clear the bottom line of the display;
 729          * just print the prompt since the forward movement guarantees
 730          * that we're in the right position to display the prompt.
 731          * Clearing the line could cause a problem: for example, if the last
 732          * line displayed ended at the right screen edge without a newline,
 733          * then clearing would clear the last displayed line rather than
 734          * the prompt line.
 735          */
 736         if (!forw_prompt)
 737                 clear_bot();
 738         clear_cmd();
 739         forw_prompt = 0;
 740         p = pr_string();
 741         if (is_filtering())
 742                 putstr("& ");
 743         if (p == NULL || *p == '\0')
 744                 putchr(':');
 745         else
 746         {
 747                 at_enter(AT_STANDOUT);
 748                 putstr(p);
 749                 at_exit();
 750         }
 751         clear_eol();
 752 }
 753
 754 /*
 755  * Display the less version message.
 756  */
 757         public void
 758 dispversion()
 759 {
 760         PARG parg;
 761
 762         parg.p_string = version;
 763         error("less %s", &parg);
 764 }
 765
 766 /*
 767  * Get command character.
 768  * The character normally comes from the keyboard,
 769  * but may come from ungotten characters
 770  * (characters previously given to ungetcc or ungetsc).
 771  */
 772         public int
 773 getcc()
 774 {
 775         if (unget_end)
 776         {
 777                 /*
 778                  * We have just run out of ungotten chars.
 779                  */
 780                 unget_end = 0;
 781                 if (len_cmdbuf() == 0 || !empty_screen())
 782                         return (getchr());
 783                 /*
 784                  * Command is incomplete, so try to complete it.
 785                  */
 786                 switch (mca)
 787                 {
 788                 case A_DIGIT:
 789                         /*
 790                          * We have a number but no command.  Treat as #g.
 791                          */
 792                         return ('g');
 793
 794                 case A_F_SEARCH:
 795                 case A_B_SEARCH:
 796                         /*
 797                          * We have "/string" but no newline.  Add the \n.
 798                          */
 799                         return ('\n');
 800
 801                 default:
 802                         /*
 803                          * Some other incomplete command.  Let user complete it.
 804                          */
 805                         return (getchr());
 806                 }
 807         }
 808
 809         if (ungot == NULL)
 810         {
 811                 /*
 812                  * Normal case: no ungotten chars, so get one from the user.
 813                  */
 814                 return (getchr());
 815         }
 816
 817         /*
 818          * Return the next ungotten char.
 819          */
 820         {
 821                 struct ungot *ug = ungot;
 822                 char c = ug->ug_char;
 823                 ungot = ug->ug_next;
 824                 free(ug);
 825                 unget_end = (ungot == NULL);
 826                 return (c);
 827         }
 828 }
 829
 830 /*
 831  * "Unget" a command character.
 832  * The next getcc() will return this character.
 833  */
 834         public void
 835 ungetcc(c)
 836         int c;
 837 {
 838         struct ungot *ug = (struct ungot *) ecalloc(1, sizeof(struct ungot));
 839
 840         ug->ug_char = c;
 841         ug->ug_next = ungot;
 842         ungot = ug;
 843         unget_end = 0;
 844 }
 845
 846 /*
 847  * Unget a whole string of command characters.
 848  * The next sequence of getcc()'s will return this string.
 849  */
 850         public void
 851 ungetsc(s)
 852         char *s;
 853 {
 854         register char *p;
 855
 856         for (p = s + strlen(s) - 1;  p >= s;  p--)
 857                 ungetcc(*p);
 858 }
 859
 860 /*
 861  * Search for a pattern, possibly in multiple files.
 862  * If SRCH_FIRST_FILE is set, begin searching at the first file.
 863  * If SRCH_PAST_EOF is set, continue the search thru multiple files.
 864  */
 865         static void
 866 multi_search(pattern, n)
 867         char *pattern;
 868         int n;
 869 {
 870         register int nomore;
 871         IFILE save_ifile;
 872         int changed_file;
 873
 874         changed_file = 0;
 875         save_ifile = save_curr_ifile();
 876
 877         if (search_type & SRCH_FIRST_FILE)
 878         {
 879                 /*
 880                  * Start at the first (or last) file
 881                  * in the command line list.
 882                  */
 883                 if (search_type & SRCH_FORW)
 884                         nomore = edit_first();
 885                 else
 886                         nomore = edit_last();
 887                 if (nomore)
 888                 {
 889                         unsave_ifile(save_ifile);
 890                         return;
 891                 }
 892                 changed_file = 1;
 893                 search_type &= ~SRCH_FIRST_FILE;
 894         }
 895
 896         for (;;)
 897         {
 898                 n = search(search_type, pattern, n);
 899                 /*
 900                  * The SRCH_NO_MOVE flag doesn't "stick": it gets cleared
 901                  * after being used once.  This allows "n" to work after
 902                  * using a /@@ search.
 903                  */
 904                 search_type &= ~SRCH_NO_MOVE;
 905                 if (n == 0)
 906                 {
 907                         /*
 908                          * Found it.
 909                          */
 910                         unsave_ifile(save_ifile);
 911                         return;
 912                 }
 913
 914                 if (n < 0)
 915                         /*
 916                          * Some kind of error in the search.
 917                          * Error message has been printed by search().
 918                          */
 919                         break;
 920
 921                 if ((search_type & SRCH_PAST_EOF) == 0)
 922                         /*
 923                          * We didn't find a match, but we're
 924                          * supposed to search only one file.
 925                          */
 926                         break;
 927                 /*
 928                  * Move on to the next file.
 929                  */
 930                 if (search_type & SRCH_FORW)
 931                         nomore = edit_next(1);
 932                 else
 933                         nomore = edit_prev(1);
 934                 if (nomore)
 935                         break;
 936                 changed_file = 1;
 937         }
 938
 939         /*
 940          * Didn't find it.
 941          * Print an error message if we haven't already.
 942          */
 943         if (n > 0)
 944                 error("Pattern not found", NULL_PARG);
 945
 946         if (changed_file)
 947         {
 948                 /*
 949                  * Restore the file we were originally viewing.
 950                  */
 951                 reedit_ifile(save_ifile);
 952         } else
 953         {
 954                 unsave_ifile(save_ifile);
 955         }
 956 }
 957
 958 /*
 959  * Main command processor.
 960  * Accept and execute commands until a quit command.
 961  */
 962         public void
 963 commands()
 964 {
 965         register int c;
 966         register int action;
 967         register char *cbuf;
 968         int newaction;
 969         int save_search_type;
 970         char *extra;
 971         char tbuf[2];
 972         PARG parg;
 973         IFILE old_ifile;
 974         IFILE new_ifile;
 975         char *tagfile;
 976
 977         search_type = SRCH_FORW;
 978         wscroll = (sc_height + 1) / 2;
 979         newaction = A_NOACTION;
 980
 981         for (;;)
 982         {
 983                 mca = 0;
 984                 cmd_accept();
 985                 number = 0;
 986                 curropt = NULL;
 987
 988                 /*
 989                  * See if any signals need processing.
 990                  */
 991                 if (sigs)
 992                 {
 993                         psignals();
 994                         if (quitting)
 995                                 quit(QUIT_SAVED_STATUS);
 996                 }
 997
 998                 /*
 999                  * See if window size changed, for systems that don't
1000                  * generate SIGWINCH.
1001                  */
1002                 check_winch();
1003
1004                 /*
1005                  * Display prompt and accept a character.
1006                  */
1007                 cmd_reset();
1008                 prompt();
1009                 if (sigs)
1010                         continue;
1011                 if (newaction == A_NOACTION)
1012                         c = getcc();
1013
1014         again:
1015                 if (sigs)
1016                         continue;
1017
1018                 if (newaction != A_NOACTION)
1019                 {
1020                         action = newaction;
1021                         newaction = A_NOACTION;
1022                 } else
1023                 {
1024                         /*
1025                          * If we are in a multicharacter command, call mca_char.
1026                          * Otherwise we call fcmd_decode to determine the
1027                          * action to be performed.
1028                          */
1029                         if (mca)
1030                                 switch (mca_char(c))
1031                                 {
1032                                 case MCA_MORE:
1033                                         /*
1034                                          * Need another character.
1035                                          */
1036                                         c = getcc();
1037                                         goto again;
1038                                 case MCA_DONE:
1039                                         /*
1040                                          * Command has been handled by mca_char.
1041                                          * Start clean with a prompt.
1042                                          */
1043                                         continue;
1044                                 case NO_MCA:
1045                                         /*
1046                                          * Not a multi-char command
1047                                          * (at least, not anymore).
1048                                          */
1049                                         break;
1050                                 }
1051
1052                         /*
1053                          * Decode the command character and decide what to do.
1054                          */
1055                         if (mca)
1056                         {
1057                                 /*
1058                                  * We're in a multichar command.
1059                                  * Add the character to the command buffer
1060                                  * and display it on the screen.
1061                                  * If the user backspaces past the start
1062                                  * of the line, abort the command.
1063                                  */
1064                                 if (cmd_char(c) == CC_QUIT || len_cmdbuf() == 0)
1065                                         continue;
1066                                 cbuf = get_cmdbuf();
1067                         } else
1068                         {
1069                                 /*
1070                                  * Don't use cmd_char if we're starting fresh
1071                                  * at the beginning of a command, because we
1072                                  * don't want to echo the command until we know
1073                                  * it is a multichar command.  We also don't
1074                                  * want erase_char/kill_char to be treated
1075                                  * as line editing characters.
1076                                  */
1077                                 tbuf[0] = c;
1078                                 tbuf[1] = '\0';
1079                                 cbuf = tbuf;
1080                         }
1081                         extra = NULL;
1082                         action = fcmd_decode(cbuf, &extra);
1083                         /*
1084                          * If an "extra" string was returned,
1085                          * process it as a string of command characters.
1086                          */
1087                         if (extra != NULL)
1088                                 ungetsc(extra);
1089                 }
1090                 /*
1091                  * Clear the cmdbuf string.
1092                  * (But not if we're in the prefix of a command,
1093                  * because the partial command string is kept there.)
1094                  */
1095                 if (action != A_PREFIX)
1096                         cmd_reset();
1097
1098                 switch (action)
1099                 {
1100                 case A_DIGIT:
1101                         /*
1102                          * First digit of a number.
1103                          */
1104                         start_mca(A_DIGIT, ":", (void*)NULL, CF_QUIT_ON_ERASE);
1105                         goto again;
1106
1107                 case A_F_WINDOW:
1108                         /*
1109                          * Forward one window (and set the window size).
1110                          */
1111                         if (number > 0)
1112                                 swindow = (int) number;
1113                         /* FALLTHRU */
1114                 case A_F_SCREEN:
1115                         /*
1116                          * Forward one screen.
1117                          */
1118                         if (number <= 0)
1119                                 number = get_swindow();
1120                         cmd_exec();
1121                         if (show_attn)
1122                                 set_attnpos(bottompos);
1123                         forward((int) number, 0, 1);
1124                         break;
1125
1126                 case A_B_WINDOW:
1127                         /*
1128                          * Backward one window (and set the window size).
1129                          */
1130                         if (number > 0)
1131                                 swindow = (int) number;
1132                         /* FALLTHRU */
1133                 case A_B_SCREEN:
1134                         /*
1135                          * Backward one screen.
1136                          */
1137                         if (number <= 0)
1138                                 number = get_swindow();
1139                         cmd_exec();
1140                         backward((int) number, 0, 1);
1141                         break;
1142
1143                 case A_F_LINE:
1144                         /*
1145                          * Forward N (default 1) line.
1146                          */
1147                         if (number <= 0)
1148                                 number = 1;
1149                         cmd_exec();
1150                         if (show_attn == OPT_ONPLUS && number > 1)
1151                                 set_attnpos(bottompos);
1152                         forward((int) number, 0, 0);
1153                         break;
1154
1155                 case A_B_LINE:
1156                         /*
1157                          * Backward N (default 1) line.
1158                          */
1159                         if (number <= 0)
1160                                 number = 1;
1161                         cmd_exec();
1162                         backward((int) number, 0, 0);
1163                         break;
1164
1165                 case A_FF_LINE:
1166                         /*
1167                          * Force forward N (default 1) line.
1168                          */
1169                         if (number <= 0)
1170                                 number = 1;
1171                         cmd_exec();
1172                         if (show_attn == OPT_ONPLUS && number > 1)
1173                                 set_attnpos(bottompos);
1174                         forward((int) number, 1, 0);
1175                         break;
1176
1177                 case A_BF_LINE:
1178                         /*
1179                          * Force backward N (default 1) line.
1180                          */
1181                         if (number <= 0)
1182                                 number = 1;
1183                         cmd_exec();
1184                         backward((int) number, 1, 0);
1185                         break;
1186
1187                 case A_FF_SCREEN:
1188                         /*
1189                          * Force forward one screen.
1190                          */
1191                         if (number <= 0)
1192                                 number = get_swindow();
1193                         cmd_exec();
1194                         if (show_attn == OPT_ONPLUS)
1195                                 set_attnpos(bottompos);
1196                         forward((int) number, 1, 0);
1197                         break;
1198
1199                 case A_F_FOREVER:
1200                         /*
1201                          * Forward forever, ignoring EOF.
1202                          */
1203                         if (ch_getflags() & CH_HELPFILE)
1204                                 break;
1205                         cmd_exec();
1206                         jump_forw();
1207                         ignore_eoi = 1;
1208                         while (!sigs)
1209                         {
1210                                 make_display();
1211                                 forward(1, 0, 0);
1212                         }
1213                         ignore_eoi = 0;
1214                         /*
1215                          * This gets us back in "F mode" after processing
1216                          * a non-abort signal (e.g. window-change).
1217                          */
1218                         if (sigs && !ABORT_SIGS())
1219                                 newaction = A_F_FOREVER;
1220                         break;
1221
1222                 case A_F_SCROLL:
1223                         /*
1224                          * Forward N lines
1225                          * (default same as last 'd' or 'u' command).
1226                          */
1227                         if (number > 0)
1228                                 wscroll = (int) number;
1229                         cmd_exec();
1230                         if (show_attn == OPT_ONPLUS)
1231                                 set_attnpos(bottompos);
1232                         forward(wscroll, 0, 0);
1233                         break;
1234
1235                 case A_B_SCROLL:
1236                         /*
1237                          * Forward N lines
1238                          * (default same as last 'd' or 'u' command).
1239                          */
1240                         if (number > 0)
1241                                 wscroll = (int) number;
1242                         cmd_exec();
1243                         backward(wscroll, 0, 0);
1244                         break;
1245
1246                 case A_FREPAINT:
1247                         /*
1248                          * Flush buffers, then repaint screen.
1249                          * Don't flush the buffers on a pipe!
1250                          */
1251                         clear_buffers();
1252                         /* FALLTHRU */
1253                 case A_REPAINT:
1254                         /*
1255                          * Repaint screen.
1256                          */
1257                         cmd_exec();
1258                         repaint();
1259                         break;
1260
1261                 case A_GOLINE:
1262                         /*
1263                          * Go to line N, default beginning of file.
1264                          */
1265                         if (number <= 0)
1266                                 number = 1;
1267                         cmd_exec();
1268                         jump_back(number);
1269                         break;
1270
1271                 case A_PERCENT:
1272                         /*
1273                          * Go to a specified percentage into the file.
1274                          */
1275                         if (number < 0)
1276                         {
1277                                 number = 0;
1278                                 fraction = 0;
1279                         }
1280                         if (number > 100)
1281                         {
1282                                 number = 100;
1283                                 fraction = 0;
1284                         }
1285                         cmd_exec();
1286                         jump_percent((int) number, fraction);
1287                         break;
1288
1289                 case A_GOEND:
1290                         /*
1291                          * Go to line N, default end of file.
1292                          */
1293                         cmd_exec();
1294                         if (number <= 0)
1295                                 jump_forw();
1296                         else
1297                                 jump_back(number);
1298                         break;
1299
1300                 case A_GOPOS:
1301                         /*
1302                          * Go to a specified byte position in the file.
1303                          */
1304                         cmd_exec();
1305                         if (number < 0)
1306                                 number = 0;
1307                         jump_line_loc((POSITION) number, jump_sline);
1308                         break;
1309
1310                 case A_STAT:
1311                         /*
1312                          * Print file name, etc.
1313                          */
1314                         if (ch_getflags() & CH_HELPFILE)
1315                                 break;
1316                         cmd_exec();
1317                         parg.p_string = eq_message();
1318                         error("%s", &parg);
1319                         break;
1320
1321                 case A_VERSION:
1322                         /*
1323                          * Print version number, without the "@(#)".
1324                          */
1325                         cmd_exec();
1326                         dispversion();
1327                         break;
1328
1329                 case A_QUIT:
1330                         /*
1331                          * Exit.
1332                          */
1333                         if (curr_ifile != NULL_IFILE &&
1334                             ch_getflags() & CH_HELPFILE)
1335                         {
1336                                 /*
1337                                  * Quit while viewing the help file
1338                                  * just means return to viewing the
1339                                  * previous file.
1340                                  */
1341                                 hshift = save_hshift;
1342                                 if (edit_prev(1) == 0)
1343                                         break;
1344                         }
1345                         if (extra != NULL)
1346                                 quit(*extra);
1347                         quit(QUIT_OK);
1348                         break;
1349
1350 /*
1351  * Define abbreviation for a commonly used sequence below.
1352  */
1353 #define DO_SEARCH() \
1354                         if (number <= 0) number = 1;    \
1355                         mca_search();                   \
1356                         cmd_exec();                     \
1357                         multi_search((char *)NULL, (int) number);
1358
1359
1360                 case A_F_SEARCH:
1361                         /*
1362                          * Search forward for a pattern.
1363                          * Get the first char of the pattern.
1364                          */
1365                         search_type = SRCH_FORW;
1366                         if (number <= 0)
1367                                 number = 1;
1368                         mca_search();
1369                         c = getcc();
1370                         goto again;
1371
1372                 case A_B_SEARCH:
1373                         /*
1374                          * Search backward for a pattern.
1375                          * Get the first char of the pattern.
1376                          */
1377                         search_type = SRCH_BACK;
1378                         if (number <= 0)
1379                                 number = 1;
1380                         mca_search();
1381                         c = getcc();
1382                         goto again;
1383
1384                 case A_FILTER:
1385 #if HILITE_SEARCH
1386                         search_type = SRCH_FORW | SRCH_FILTER;
1387                         mca_search();
1388                         c = getcc();
1389                         goto again;
1390 #else
1391                         error("Command not available", NULL_PARG);
1392                         break;
1393 #endif
1394
1395                 case A_AGAIN_SEARCH:
1396                         /*
1397                          * Repeat previous search.
1398                          */
1399                         DO_SEARCH();
1400                         break;
1401
1402                 case A_T_AGAIN_SEARCH:
1403                         /*
1404                          * Repeat previous search, multiple files.
1405                          */
1406                         search_type |= SRCH_PAST_EOF;
1407                         DO_SEARCH();
1408                         break;
1409
1410                 case A_REVERSE_SEARCH:
1411                         /*
1412                          * Repeat previous search, in reverse direction.
1413                          */
1414                         save_search_type = search_type;
1415                         search_type = SRCH_REVERSE(search_type);
1416                         DO_SEARCH();
1417                         search_type = save_search_type;
1418                         break;
1419
1420                 case A_T_REVERSE_SEARCH:
1421                         /*
1422                          * Repeat previous search,
1423                          * multiple files in reverse direction.
1424                          */
1425                         save_search_type = search_type;
1426                         search_type = SRCH_REVERSE(search_type);
1427                         search_type |= SRCH_PAST_EOF;
1428                         DO_SEARCH();
1429                         search_type = save_search_type;
1430                         break;
1431
1432                 case A_UNDO_SEARCH:
1433                         undo_search();
1434                         break;
1435
1436                 case A_HELP:
1437                         /*
1438                          * Help.
1439                          */
1440                         if (ch_getflags() & CH_HELPFILE)
1441                                 break;
1442                         cmd_exec();
1443                         save_hshift = hshift;
1444                         hshift = 0;
1445                         (void) edit(FAKE_HELPFILE);
1446                         break;
1447
1448                 case A_EXAMINE:
1449 #if EXAMINE
1450                         /*
1451                          * Edit a new file.  Get the filename.
1452                          */
1453                         if (secure)
1454                         {
1455                                 error("Command not available", NULL_PARG);
1456                                 break;
1457                         }
1458                         start_mca(A_EXAMINE, "Examine: ", ml_examine, 0);
1459                         c = getcc();
1460                         goto again;
1461 #else
1462                         error("Command not available", NULL_PARG);
1463                         break;
1464 #endif
1465
1466                 case A_VISUAL:
1467                         /*
1468                          * Invoke an editor on the input file.
1469                          */
1470 #if EDITOR
1471                         if (secure)
1472                         {
1473                                 error("Command not available", NULL_PARG);
1474                                 break;
1475                         }
1476                         if (ch_getflags() & CH_HELPFILE)
1477                                 break;
1478                         if (strcmp(get_filename(curr_ifile), "-") == 0)
1479                         {
1480                                 error("Cannot edit standard input", NULL_PARG);
1481                                 break;
1482                         }
1483                         if (curr_altfilename != NULL)
1484                         {
1485                                 error("WARNING: This file was viewed via LESSOPEN",
1486                                         NULL_PARG);
1487                         }
1488                         start_mca(A_SHELL, "!", ml_shell, 0);
1489                         /*
1490                          * Expand the editor prototype string
1491                          * and pass it to the system to execute.
1492                          * (Make sure the screen is displayed so the
1493                          * expansion of "+%lm" works.)
1494                          */
1495                         make_display();
1496                         cmd_exec();
1497                         lsystem(pr_expand(editproto, 0), (char*)NULL);
1498                         break;
1499 #else
1500                         error("Command not available", NULL_PARG);
1501                         break;
1502 #endif
1503
1504                 case A_NEXT_FILE:
1505                         /*
1506                          * Examine next file.
1507                          */
1508 #if TAGS
1509                         if (ntags())
1510                         {
1511                                 error("No next file", NULL_PARG);
1512                                 break;
1513                         }
1514 #endif
1515                         if (number <= 0)
1516                                 number = 1;
1517                         if (edit_next((int) number))
1518                         {
1519                                 if (get_quit_at_eof() && eof_displayed() &&
1520                                     !(ch_getflags() & CH_HELPFILE))
1521                                         quit(QUIT_OK);
1522                                 parg.p_string = (number > 1) ? "(N-th) " : "";
1523                                 error("No %snext file", &parg);
1524                         }
1525                         break;
1526
1527                 case A_PREV_FILE:
1528                         /*
1529                          * Examine previous file.
1530                          */
1531 #if TAGS
1532                         if (ntags())
1533                         {
1534                                 error("No previous file", NULL_PARG);
1535                                 break;
1536                         }
1537 #endif
1538                         if (number <= 0)
1539                                 number = 1;
1540                         if (edit_prev((int) number))
1541                         {
1542                                 parg.p_string = (number > 1) ? "(N-th) " : "";
1543                                 error("No %sprevious file", &parg);
1544                         }
1545                         break;
1546
1547                 case A_NEXT_TAG:
1548 #if TAGS
1549                         if (number <= 0)
1550                                 number = 1;
1551                         tagfile = nexttag((int) number);
1552                         if (tagfile == NULL)
1553                         {
1554                                 error("No next tag", NULL_PARG);
1555                                 break;
1556                         }
1557                         if (edit(tagfile) == 0)
1558                         {
1559                                 POSITION pos = tagsearch();
1560                                 if (pos != NULL_POSITION)
1561                                         jump_loc(pos, jump_sline);
1562                         }
1563 #else
1564                         error("Command not available", NULL_PARG);
1565 #endif
1566                         break;
1567
1568                 case A_PREV_TAG:
1569 #if TAGS
1570                         if (number <= 0)
1571                                 number = 1;
1572                         tagfile = prevtag((int) number);
1573                         if (tagfile == NULL)
1574                         {
1575                                 error("No previous tag", NULL_PARG);
1576                                 break;
1577                         }
1578                         if (edit(tagfile) == 0)
1579                         {
1580                                 POSITION pos = tagsearch();
1581                                 if (pos != NULL_POSITION)
1582                                         jump_loc(pos, jump_sline);
1583                         }
1584 #else
1585                         error("Command not available", NULL_PARG);
1586 #endif
1587                         break;
1588
1589                 case A_INDEX_FILE:
1590                         /*
1591                          * Examine a particular file.
1592                          */
1593                         if (number <= 0)
1594                                 number = 1;
1595                         if (edit_index((int) number))
1596                                 error("No such file", NULL_PARG);
1597                         break;
1598
1599                 case A_REMOVE_FILE:
1600                         if (ch_getflags() & CH_HELPFILE)
1601                                 break;
1602                         old_ifile = curr_ifile;
1603                         new_ifile = getoff_ifile(curr_ifile);
1604                         if (new_ifile == NULL_IFILE)
1605                         {
1606                                 bell();
1607                                 break;
1608                         }
1609                         if (edit_ifile(new_ifile) != 0)
1610                         {
1611                                 reedit_ifile(old_ifile);
1612                                 break;
1613                         }
1614                         del_ifile(old_ifile);
1615                         break;
1616
1617                 case A_OPT_TOGGLE:
1618                         optflag = OPT_TOGGLE;
1619                         optgetname = FALSE;
1620                         mca_opt_toggle();
1621                         c = getcc();
1622                         goto again;
1623
1624                 case A_DISP_OPTION:
1625                         /*
1626                          * Report a flag setting.
1627                          */
1628                         optflag = OPT_NO_TOGGLE;
1629                         optgetname = FALSE;
1630                         mca_opt_toggle();
1631                         c = getcc();
1632                         goto again;
1633
1634                 case A_FIRSTCMD:
1635                         /*
1636                          * Set an initial command for new files.
1637                          */
1638                         start_mca(A_FIRSTCMD, "+", (void*)NULL, 0);
1639                         c = getcc();
1640                         goto again;
1641
1642                 case A_SHELL:
1643                         /*
1644                          * Shell escape.
1645                          */
1646 #if SHELL_ESCAPE
1647                         if (secure)
1648                         {
1649                                 error("Command not available", NULL_PARG);
1650                                 break;
1651                         }
1652                         start_mca(A_SHELL, "!", ml_shell, 0);
1653                         c = getcc();
1654                         goto again;
1655 #else
1656                         error("Command not available", NULL_PARG);
1657                         break;
1658 #endif
1659
1660                 case A_SETMARK:
1661                         /*
1662                          * Set a mark.
1663                          */
1664                         if (ch_getflags() & CH_HELPFILE)
1665                                 break;
1666                         start_mca(A_SETMARK, "mark: ", (void*)NULL, 0);
1667                         c = getcc();
1668                         if (c == erase_char || c == erase2_char ||
1669                             c == kill_char || c == '\n' || c == '\r')
1670                                 break;
1671                         setmark(c);
1672                         break;
1673
1674                 case A_GOMARK:
1675                         /*
1676                          * Go to a mark.
1677                          */
1678                         start_mca(A_GOMARK, "goto mark: ", (void*)NULL, 0);
1679                         c = getcc();
1680                         if (c == erase_char || c == erase2_char ||
1681                             c == kill_char || c == '\n' || c == '\r')
1682                                 break;
1683                         cmd_exec();
1684                         gomark(c);
1685                         break;
1686
1687                 case A_PIPE:
1688 #if PIPEC
1689                         if (secure)
1690                         {
1691                                 error("Command not available", NULL_PARG);
1692                                 break;
1693                         }
1694                         start_mca(A_PIPE, "|mark: ", (void*)NULL, 0);
1695                         c = getcc();
1696                         if (c == erase_char || c == erase2_char || c == kill_char)
1697                                 break;
1698                         if (c == '\n' || c == '\r')
1699                                 c = '.';
1700                         if (badmark(c))
1701                                 break;
1702                         pipec = c;
1703                         start_mca(A_PIPE, "!", ml_shell, 0);
1704                         c = getcc();
1705                         goto again;
1706 #else
1707                         error("Command not available", NULL_PARG);
1708                         break;
1709 #endif
1710
1711                 case A_B_BRACKET:
1712                 case A_F_BRACKET:
1713                         start_mca(action, "Brackets: ", (void*)NULL, 0);
1714                         c = getcc();
1715                         goto again;
1716
1717                 case A_LSHIFT:
1718                         if (number > 0)
1719                                 shift_count = number;
1720                         else
1721                                 number = (shift_count > 0) ?
1722                                         shift_count : sc_width / 2;
1723                         if (number > hshift)
1724                                 number = hshift;
1725                         hshift -= number;
1726                         screen_trashed = 1;
1727                         break;
1728
1729                 case A_RSHIFT:
1730                         if (number > 0)
1731                                 shift_count = number;
1732                         else
1733                                 number = (shift_count > 0) ?
1734                                         shift_count : sc_width / 2;
1735                         hshift += number;
1736                         screen_trashed = 1;
1737                         break;
1738
1739                 case A_PREFIX:
1740                         /*
1741                          * The command is incomplete (more chars are needed).
1742                          * Display the current char, so the user knows
1743                          * what's going on, and get another character.
1744                          */
1745                         if (mca != A_PREFIX)
1746                         {
1747                                 cmd_reset();
1748                                 start_mca(A_PREFIX, " ", (void*)NULL,
1749                                         CF_QUIT_ON_ERASE);
1750                                 (void) cmd_char(c);
1751                         }
1752                         c = getcc();
1753                         goto again;
1754
1755                 case A_NOACTION:
1756                         break;
1757
1758                 default:
1759                         bell();
1760                         break;
1761                 }
1762         }
1763 }