contrib/less/command.c

   1 /*
   2  * Copyright (C) 1984-2009  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 static char ungot[UNGOT_SIZE];
  59 static char *ungotp = NULL;
  60 #if SHELL_ESCAPE
  61 static char *shellcmd = NULL;   /* For holding last shell command for "!!" */
  62 #endif
  63 static int mca;                 /* The multicharacter command (action) */
  64 static int search_type;         /* The previous type of search */
  65 static LINENUM number;          /* The number typed by the user */
  66 static long fraction;           /* The fractional part of the number */
  67 static char optchar;
  68 static int optflag;
  69 static int optgetname;
  70 static POSITION bottompos;
  71 static int save_hshift;
  72 #if PIPEC
  73 static char pipec;
  74 #endif
  75
  76 static void multi_search();
  77
  78 /*
  79  * Move the cursor to start of prompt line before executing a command.
  80  * This looks nicer if the command takes a long time before
  81  * updating the screen.
  82  */
  83         static void
  84 cmd_exec()
  85 {
  86 #if HILITE_SEARCH
  87         clear_attn();
  88 #endif
  89         clear_bot();
  90         flush();
  91 }
  92
  93 /*
  94  * Set up the display to start a new multi-character command.
  95  */
  96         static void
  97 start_mca(action, prompt, mlist, cmdflags)
  98         int action;
  99         char *prompt;
 100         void *mlist;
 101         int cmdflags;
 102 {
 103         mca = action;
 104         clear_bot();
 105         clear_cmd();
 106         cmd_putstr(prompt);
 107         set_mlist(mlist, cmdflags);
 108 }
 109
 110         public int
 111 in_mca()
 112 {
 113         return (mca != 0 && mca != A_PREFIX);
 114 }
 115
 116 /*
 117  * Set up the display to start a new search command.
 118  */
 119         static void
 120 mca_search()
 121 {
 122 #if HILITE_SEARCH
 123         if (search_type & SRCH_FILTER)
 124                 mca = A_FILTER;
 125         else
 126 #endif
 127         if (search_type & SRCH_FORW)
 128                 mca = A_F_SEARCH;
 129         else
 130                 mca = A_B_SEARCH;
 131
 132         clear_bot();
 133         clear_cmd();
 134
 135         if (search_type & SRCH_NO_MATCH)
 136                 cmd_putstr("Non-match ");
 137         if (search_type & SRCH_FIRST_FILE)
 138                 cmd_putstr("First-file ");
 139         if (search_type & SRCH_PAST_EOF)
 140                 cmd_putstr("EOF-ignore ");
 141         if (search_type & SRCH_NO_MOVE)
 142                 cmd_putstr("Keep-pos ");
 143         if (search_type & SRCH_NO_REGEX)
 144                 cmd_putstr("Regex-off ");
 145
 146 #if HILITE_SEARCH
 147         if (search_type & SRCH_FILTER)
 148                 cmd_putstr("&/");
 149         else
 150 #endif
 151         if (search_type & SRCH_FORW)
 152                 cmd_putstr("/");
 153         else
 154                 cmd_putstr("?");
 155         set_mlist(ml_search, 0);
 156 }
 157
 158 /*
 159  * Set up the display to start a new toggle-option command.
 160  */
 161         static void
 162 mca_opt_toggle()
 163 {
 164         int no_prompt;
 165         int flag;
 166         char *dash;
 167
 168         no_prompt = (optflag & OPT_NO_PROMPT);
 169         flag = (optflag & ~OPT_NO_PROMPT);
 170         dash = (flag == OPT_NO_TOGGLE) ? "_" : "-";
 171
 172         mca = A_OPT_TOGGLE;
 173         clear_bot();
 174         clear_cmd();
 175         cmd_putstr(dash);
 176         if (optgetname)
 177                 cmd_putstr(dash);
 178         if (no_prompt)
 179                 cmd_putstr("(P)");
 180         switch (flag)
 181         {
 182         case OPT_UNSET:
 183                 cmd_putstr("+");
 184                 break;
 185         case OPT_SET:
 186                 cmd_putstr("!");
 187                 break;
 188         }
 189         set_mlist(NULL, 0);
 190 }
 191
 192 /*
 193  * Execute a multicharacter command.
 194  */
 195         static void
 196 exec_mca()
 197 {
 198         register char *cbuf;
 199
 200         cmd_exec();
 201         cbuf = get_cmdbuf();
 202
 203         switch (mca)
 204         {
 205         case A_F_SEARCH:
 206         case A_B_SEARCH:
 207                 multi_search(cbuf, (int) number);
 208                 break;
 209 #if HILITE_SEARCH
 210         case A_FILTER:
 211                 search_type ^= SRCH_NO_MATCH;
 212                 set_filter_pattern(cbuf, search_type);
 213                 break;
 214 #endif
 215         case A_FIRSTCMD:
 216                 /*
 217                  * Skip leading spaces or + signs in the string.
 218                  */
 219                 while (*cbuf == '+' || *cbuf == ' ')
 220                         cbuf++;
 221                 if (every_first_cmd != NULL)
 222                         free(every_first_cmd);
 223                 if (*cbuf == '\0')
 224                         every_first_cmd = NULL;
 225                 else
 226                         every_first_cmd = save(cbuf);
 227                 break;
 228         case A_OPT_TOGGLE:
 229                 toggle_option(optchar, cbuf, optflag);
 230                 optchar = '\0';
 231                 break;
 232         case A_F_BRACKET:
 233                 match_brac(cbuf[0], cbuf[1], 1, (int) number);
 234                 break;
 235         case A_B_BRACKET:
 236                 match_brac(cbuf[1], cbuf[0], 0, (int) number);
 237                 break;
 238 #if EXAMINE
 239         case A_EXAMINE:
 240                 if (secure)
 241                         break;
 242                 edit_list(cbuf);
 243 #if TAGS
 244                 /* If tag structure is loaded then clean it up. */
 245                 cleantags();
 246 #endif
 247                 break;
 248 #endif
 249 #if SHELL_ESCAPE
 250         case A_SHELL:
 251                 /*
 252                  * !! just uses whatever is in shellcmd.
 253                  * Otherwise, copy cmdbuf to shellcmd,
 254                  * expanding any special characters ("%" or "#").
 255                  */
 256                 if (*cbuf != '!')
 257                 {
 258                         if (shellcmd != NULL)
 259                                 free(shellcmd);
 260                         shellcmd = fexpand(cbuf);
 261                 }
 262
 263                 if (secure)
 264                         break;
 265                 if (shellcmd == NULL)
 266                         lsystem("", "!done");
 267                 else
 268                         lsystem(shellcmd, "!done");
 269                 break;
 270 #endif
 271 #if PIPEC
 272         case A_PIPE:
 273                 if (secure)
 274                         break;
 275                 (void) pipe_mark(pipec, cbuf);
 276                 error("|done", NULL_PARG);
 277                 break;
 278 #endif
 279         }
 280 }
 281
 282 /*
 283  * Add a character to a multi-character command.
 284  */
 285         static int
 286 mca_char(c)
 287         int c;
 288 {
 289         char *p;
 290         int flag;
 291         char buf[3];
 292         PARG parg;
 293
 294         switch (mca)
 295         {
 296         case 0:
 297                 /*
 298                  * Not in a multicharacter command.
 299                  */
 300                 return (NO_MCA);
 301
 302         case A_PREFIX:
 303                 /*
 304                  * In the prefix of a command.
 305                  * This not considered a multichar command
 306                  * (even tho it uses cmdbuf, etc.).
 307                  * It is handled in the commands() switch.
 308                  */
 309                 return (NO_MCA);
 310
 311         case A_DIGIT:
 312                 /*
 313                  * Entering digits of a number.
 314                  * Terminated by a non-digit.
 315                  */
 316                 if (!((c >= '0' && c <= '9') || c == '.') &&
 317                   editchar(c, EC_PEEK|EC_NOHISTORY|EC_NOCOMPLETE|EC_NORIGHTLEFT) == A_INVALID)
 318                 {
 319                         /*
 320                          * Not part of the number.
 321                          * Treat as a normal command character.
 322                          */
 323                         number = cmd_int(&fraction);
 324                         mca = 0;
 325                         cmd_accept();
 326                         return (NO_MCA);
 327                 }
 328                 break;
 329
 330         case A_OPT_TOGGLE:
 331                 /*
 332                  * Special case for the TOGGLE_OPTION command.
 333                  * If the option letter which was entered is a
 334                  * single-char option, execute the command immediately,
 335                  * so user doesn't have to hit RETURN.
 336                  * If the first char is + or -, this indicates
 337                  * OPT_UNSET or OPT_SET respectively, instead of OPT_TOGGLE.
 338                  * "--" begins inputting a long option name.
 339                  */
 340                 if (optchar == '\0' && len_cmdbuf() == 0)
 341                 {
 342                         flag = (optflag & ~OPT_NO_PROMPT);
 343                         if (flag == OPT_NO_TOGGLE)
 344                         {
 345                                 switch (c)
 346                                 {
 347                                 case '_':
 348                                         /* "__" = long option name. */
 349                                         optgetname = TRUE;
 350                                         mca_opt_toggle();
 351                                         return (MCA_MORE);
 352                                 }
 353                         } else
 354                         {
 355                                 switch (c)
 356                                 {
 357                                 case '+':
 358                                         /* "-+" = UNSET. */
 359                                         optflag = (flag == OPT_UNSET) ?
 360                                                 OPT_TOGGLE : OPT_UNSET;
 361                                         mca_opt_toggle();
 362                                         return (MCA_MORE);
 363                                 case '!':
 364                                         /* "-!" = SET */
 365                                         optflag = (flag == OPT_SET) ?
 366                                                 OPT_TOGGLE : OPT_SET;
 367                                         mca_opt_toggle();
 368                                         return (MCA_MORE);
 369                                 case CONTROL('P'):
 370                                         optflag ^= OPT_NO_PROMPT;
 371                                         mca_opt_toggle();
 372                                         return (MCA_MORE);
 373                                 case '-':
 374                                         /* "--" = long option name. */
 375                                         optgetname = TRUE;
 376                                         mca_opt_toggle();
 377                                         return (MCA_MORE);
 378                                 }
 379                         }
 380                 }
 381                 if (optgetname)
 382                 {
 383                         /*
 384                          * We're getting a long option name.
 385                          * See if we've matched an option name yet.
 386                          * If so, display the complete name and stop
 387                          * accepting chars until user hits RETURN.
 388                          */
 389                         struct loption *o;
 390                         char *oname;
 391                         int lc;
 392
 393                         if (c == '\n' || c == '\r')
 394                         {
 395                                 /*
 396                                  * When the user hits RETURN, make sure
 397                                  * we've matched an option name, then
 398                                  * pretend he just entered the equivalent
 399                                  * option letter.
 400                                  */
 401                                 if (optchar == '\0')
 402                                 {
 403                                         parg.p_string = get_cmdbuf();
 404                                         error("There is no --%s option", &parg);
 405                                         return (MCA_DONE);
 406                                 }
 407                                 optgetname = FALSE;
 408                                 cmd_reset();
 409                                 c = optchar;
 410                         } else
 411                         {
 412                                 if (optchar != '\0')
 413                                 {
 414                                         /*
 415                                          * Already have a match for the name.
 416                                          * Don't accept anything but erase/kill.
 417                                          */
 418                                         if (c == erase_char ||
 419                                             c == erase2_char ||
 420                                             c == kill_char)
 421                                                 return (MCA_DONE);
 422                                         return (MCA_MORE);
 423                                 }
 424                                 /*
 425                                  * Add char to cmd buffer and try to match
 426                                  * the option name.
 427                                  */
 428                                 if (cmd_char(c) == CC_QUIT)
 429                                         return (MCA_DONE);
 430                                 p = get_cmdbuf();
 431                                 lc = ASCII_IS_LOWER(p[0]);
 432                                 o = findopt_name(&p, &oname, NULL);
 433                                 if (o != NULL)
 434                                 {
 435                                         /*
 436                                          * Got a match.
 437                                          * Remember the option letter and
 438                                          * display the full option name.
 439                                          */
 440                                         optchar = o->oletter;
 441                                         if (!lc && ASCII_IS_LOWER(optchar))
 442                                                 optchar = ASCII_TO_UPPER(optchar);
 443                                         cmd_reset();
 444                                         mca_opt_toggle();
 445                                         for (p = oname;  *p != '\0';  p++)
 446                                         {
 447                                                 c = *p;
 448                                                 if (!lc && ASCII_IS_LOWER(c))
 449                                                         c = ASCII_TO_UPPER(c);
 450                                                 if (cmd_char(c) != CC_OK)
 451                                                         return (MCA_DONE);
 452                                         }
 453                                 }
 454                                 return (MCA_MORE);
 455                         }
 456                 } else
 457                 {
 458                         if (c == erase_char || c == erase2_char || c == kill_char)
 459                                 break;
 460                         if (optchar != '\0')
 461                                 /* We already have the option letter. */
 462                                 break;
 463                 }
 464
 465                 optchar = c;
 466                 if ((optflag & ~OPT_NO_PROMPT) != OPT_TOGGLE ||
 467                     single_char_option(c))
 468                 {
 469                         toggle_option(c, "", optflag);
 470                         return (MCA_DONE);
 471                 }
 472                 /*
 473                  * Display a prompt appropriate for the option letter.
 474                  */
 475                 if ((p = opt_prompt(c)) == NULL)
 476                 {
 477                         buf[0] = '-';
 478                         buf[1] = c;
 479                         buf[2] = '\0';
 480                         p = buf;
 481                 }
 482                 start_mca(A_OPT_TOGGLE, p, (void*)NULL, 0);
 483                 return (MCA_MORE);
 484
 485         case A_F_SEARCH:
 486         case A_B_SEARCH:
 487         case A_FILTER:
 488                 /*
 489                  * Special case for search commands.
 490                  * Certain characters as the first char of
 491                  * the pattern have special meaning:
 492                  *      !  Toggle the NO_MATCH flag
 493                  *      *  Toggle the PAST_EOF flag
 494                  *      @  Toggle the FIRST_FILE flag
 495                  */
 496                 if (len_cmdbuf() > 0)
 497                         /*
 498                          * Only works for the first char of the pattern.
 499                          */
 500                         break;
 501
 502                 flag = 0;
 503                 switch (c)
 504                 {
 505                 case CONTROL('E'): /* ignore END of file */
 506                 case '*':
 507                         if (mca != A_FILTER)
 508                                 flag = SRCH_PAST_EOF;
 509                         break;
 510                 case CONTROL('F'): /* FIRST file */
 511                 case '@':
 512                         if (mca != A_FILTER)
 513                                 flag = SRCH_FIRST_FILE;
 514                         break;
 515                 case CONTROL('K'): /* KEEP position */
 516                         if (mca != A_FILTER)
 517                                 flag = SRCH_NO_MOVE;
 518                         break;
 519                 case CONTROL('R'): /* Don't use REGULAR EXPRESSIONS */
 520                         flag = SRCH_NO_REGEX;
 521                         break;
 522                 case CONTROL('N'): /* NOT match */
 523                 case '!':
 524                         flag = SRCH_NO_MATCH;
 525                         break;
 526                 }
 527                 if (flag != 0)
 528                 {
 529                         search_type ^= flag;
 530                         mca_search();
 531                         return (MCA_MORE);
 532                 }
 533                 break;
 534         }
 535
 536         /*
 537          * Any other multicharacter command
 538          * is terminated by a newline.
 539          */
 540         if (c == '\n' || c == '\r')
 541         {
 542                 /*
 543                  * Execute the command.
 544                  */
 545                 exec_mca();
 546                 return (MCA_DONE);
 547         }
 548
 549         /*
 550          * Append the char to the command buffer.
 551          */
 552         if (cmd_char(c) == CC_QUIT)
 553                 /*
 554                  * Abort the multi-char command.
 555                  */
 556                 return (MCA_DONE);
 557
 558         if ((mca == A_F_BRACKET || mca == A_B_BRACKET) && len_cmdbuf() >= 2)
 559         {
 560                 /*
 561                  * Special case for the bracket-matching commands.
 562                  * Execute the command after getting exactly two
 563                  * characters from the user.
 564                  */
 565                 exec_mca();
 566                 return (MCA_DONE);
 567         }
 568
 569         /*
 570          * Need another character.
 571          */
 572         return (MCA_MORE);
 573 }
 574
 575 /*
 576  * Discard any buffered file data.
 577  */
 578         static void
 579 clear_buffers()
 580 {
 581         if (!(ch_getflags() & CH_CANSEEK))
 582                 return;
 583         ch_flush();
 584         clr_linenum();
 585 #if HILITE_SEARCH
 586         clr_hilite();
 587 #endif
 588 }
 589
 590 /*
 591  * Make sure the screen is displayed.
 592  */
 593         static void
 594 make_display()
 595 {
 596         /*
 597          * If nothing is displayed yet, display starting from initial_scrpos.
 598          */
 599         if (empty_screen())
 600         {
 601                 if (initial_scrpos.pos == NULL_POSITION)
 602                         /*
 603                          * {{ Maybe this should be:
 604                          *    jump_loc(ch_zero(), jump_sline);
 605                          *    but this behavior seems rather unexpected
 606                          *    on the first screen. }}
 607                          */
 608                         jump_loc(ch_zero(), 1);
 609                 else
 610                         jump_loc(initial_scrpos.pos, initial_scrpos.ln);
 611         } else if (screen_trashed)
 612         {
 613                 int save_top_scroll = top_scroll;
 614                 int save_ignore_eoi = ignore_eoi;
 615                 top_scroll = 1;
 616                 ignore_eoi = 0;
 617                 if (screen_trashed == 2)
 618                 {
 619                         /* Special case used by ignore_eoi: re-open the input file
 620                          * and jump to the end of the file. */
 621                         reopen_curr_ifile();
 622                         jump_forw();
 623                 }
 624                 repaint();
 625                 top_scroll = save_top_scroll;
 626                 ignore_eoi = save_ignore_eoi;
 627         }
 628 }
 629
 630 /*
 631  * Display the appropriate prompt.
 632  */
 633         static void
 634 prompt()
 635 {
 636         register char *p;
 637
 638         if (ungotp != NULL && ungotp > ungot)
 639         {
 640                 /*
 641                  * No prompt necessary if commands are from
 642                  * ungotten chars rather than from the user.
 643                  */
 644                 return;
 645         }
 646
 647         /*
 648          * Make sure the screen is displayed.
 649          */
 650         make_display();
 651         bottompos = position(BOTTOM_PLUS_ONE);
 652
 653         /*
 654          * If we've hit EOF on the last file and the -E flag is set, quit.
 655          */
 656         if (get_quit_at_eof() == OPT_ONPLUS &&
 657             eof_displayed() && !(ch_getflags() & CH_HELPFILE) &&
 658             next_ifile(curr_ifile) == NULL_IFILE)
 659                 quit(QUIT_OK);
 660
 661         /*
 662          * If the entire file is displayed and the -F flag is set, quit.
 663          */
 664         if (quit_if_one_screen &&
 665             entire_file_displayed() && !(ch_getflags() & CH_HELPFILE) &&
 666             next_ifile(curr_ifile) == NULL_IFILE)
 667                 quit(QUIT_OK);
 668
 669 #if MSDOS_COMPILER==WIN32C
 670         /*
 671          * In Win32, display the file name in the window title.
 672          */
 673         if (!(ch_getflags() & CH_HELPFILE))
 674                 SetConsoleTitle(pr_expand("Less?f - %f.", 0));
 675 #endif
 676         /*
 677          * Select the proper prompt and display it.
 678          */
 679         /*
 680          * If the previous action was a forward movement,
 681          * don't clear the bottom line of the display;
 682          * just print the prompt since the forward movement guarantees
 683          * that we're in the right position to display the prompt.
 684          * Clearing the line could cause a problem: for example, if the last
 685          * line displayed ended at the right screen edge without a newline,
 686          * then clearing would clear the last displayed line rather than
 687          * the prompt line.
 688          */
 689         if (!forw_prompt)
 690                 clear_bot();
 691         clear_cmd();
 692         forw_prompt = 0;
 693         p = pr_string();
 694         if (is_filtering())
 695                 putstr("& ");
 696         if (p == NULL || *p == '\0')
 697                 putchr(':');
 698         else
 699         {
 700                 at_enter(AT_STANDOUT);
 701                 putstr(p);
 702                 at_exit();
 703         }
 704         clear_eol();
 705 }
 706
 707 /*
 708  * Display the less version message.
 709  */
 710         public void
 711 dispversion()
 712 {
 713         PARG parg;
 714
 715         parg.p_string = version;
 716         error("less %s", &parg);
 717 }
 718
 719 /*
 720  * Get command character.
 721  * The character normally comes from the keyboard,
 722  * but may come from ungotten characters
 723  * (characters previously given to ungetcc or ungetsc).
 724  */
 725         public int
 726 getcc()
 727 {
 728         if (ungotp == NULL)
 729                 /*
 730                  * Normal case: no ungotten chars, so get one from the user.
 731                  */
 732                 return (getchr());
 733
 734         if (ungotp > ungot)
 735                 /*
 736                  * Return the next ungotten char.
 737                  */
 738                 return (*--ungotp);
 739
 740         /*
 741          * We have just run out of ungotten chars.
 742          */
 743         ungotp = NULL;
 744         if (len_cmdbuf() == 0 || !empty_screen())
 745                 return (getchr());
 746         /*
 747          * Command is incomplete, so try to complete it.
 748          */
 749         switch (mca)
 750         {
 751         case A_DIGIT:
 752                 /*
 753                  * We have a number but no command.  Treat as #g.
 754                  */
 755                 return ('g');
 756
 757         case A_F_SEARCH:
 758         case A_B_SEARCH:
 759                 /*
 760                  * We have "/string" but no newline.  Add the \n.
 761                  */
 762                 return ('\n');
 763
 764         default:
 765                 /*
 766                  * Some other incomplete command.  Let user complete it.
 767                  */
 768                 return (getchr());
 769         }
 770 }
 771
 772 /*
 773  * "Unget" a command character.
 774  * The next getcc() will return this character.
 775  */
 776         public void
 777 ungetcc(c)
 778         int c;
 779 {
 780         if (ungotp == NULL)
 781                 ungotp = ungot;
 782         if (ungotp >= ungot + sizeof(ungot))
 783         {
 784                 error("ungetcc overflow", NULL_PARG);
 785                 quit(QUIT_ERROR);
 786         }
 787         *ungotp++ = c;
 788 }
 789
 790 /*
 791  * Unget a whole string of command characters.
 792  * The next sequence of getcc()'s will return this string.
 793  */
 794         public void
 795 ungetsc(s)
 796         char *s;
 797 {
 798         register char *p;
 799
 800         for (p = s + strlen(s) - 1;  p >= s;  p--)
 801                 ungetcc(*p);
 802 }
 803
 804 /*
 805  * Search for a pattern, possibly in multiple files.
 806  * If SRCH_FIRST_FILE is set, begin searching at the first file.
 807  * If SRCH_PAST_EOF is set, continue the search thru multiple files.
 808  */
 809         static void
 810 multi_search(pattern, n)
 811         char *pattern;
 812         int n;
 813 {
 814         register int nomore;
 815         IFILE save_ifile;
 816         int changed_file;
 817
 818         changed_file = 0;
 819         save_ifile = save_curr_ifile();
 820
 821         if (search_type & SRCH_FIRST_FILE)
 822         {
 823                 /*
 824                  * Start at the first (or last) file
 825                  * in the command line list.
 826                  */
 827                 if (search_type & SRCH_FORW)
 828                         nomore = edit_first();
 829                 else
 830                         nomore = edit_last();
 831                 if (nomore)
 832                 {
 833                         unsave_ifile(save_ifile);
 834                         return;
 835                 }
 836                 changed_file = 1;
 837                 search_type &= ~SRCH_FIRST_FILE;
 838         }
 839
 840         for (;;)
 841         {
 842                 n = search(search_type, pattern, n);
 843                 /*
 844                  * The SRCH_NO_MOVE flag doesn't "stick": it gets cleared
 845                  * after being used once.  This allows "n" to work after
 846                  * using a /@@ search.
 847                  */
 848                 search_type &= ~SRCH_NO_MOVE;
 849                 if (n == 0)
 850                 {
 851                         /*
 852                          * Found it.
 853                          */
 854                         unsave_ifile(save_ifile);
 855                         return;
 856                 }
 857
 858                 if (n < 0)
 859                         /*
 860                          * Some kind of error in the search.
 861                          * Error message has been printed by search().
 862                          */
 863                         break;
 864
 865                 if ((search_type & SRCH_PAST_EOF) == 0)
 866                         /*
 867                          * We didn't find a match, but we're
 868                          * supposed to search only one file.
 869                          */
 870                         break;
 871                 /*
 872                  * Move on to the next file.
 873                  */
 874                 if (search_type & SRCH_FORW)
 875                         nomore = edit_next(1);
 876                 else
 877                         nomore = edit_prev(1);
 878                 if (nomore)
 879                         break;
 880                 changed_file = 1;
 881         }
 882
 883         /*
 884          * Didn't find it.
 885          * Print an error message if we haven't already.
 886          */
 887         if (n > 0)
 888                 error("Pattern not found", NULL_PARG);
 889
 890         if (changed_file)
 891         {
 892                 /*
 893                  * Restore the file we were originally viewing.
 894                  */
 895                 reedit_ifile(save_ifile);
 896         } else
 897         {
 898                 unsave_ifile(save_ifile);
 899         }
 900 }
 901
 902 /*
 903  * Main command processor.
 904  * Accept and execute commands until a quit command.
 905  */
 906         public void
 907 commands()
 908 {
 909         register int c;
 910         register int action;
 911         register char *cbuf;
 912         int newaction;
 913         int save_search_type;
 914         char *extra;
 915         char tbuf[2];
 916         PARG parg;
 917         IFILE old_ifile;
 918         IFILE new_ifile;
 919         char *tagfile;
 920
 921         search_type = SRCH_FORW;
 922         wscroll = (sc_height + 1) / 2;
 923         newaction = A_NOACTION;
 924
 925         for (;;)
 926         {
 927                 mca = 0;
 928                 cmd_accept();
 929                 number = 0;
 930                 optchar = '\0';
 931
 932                 /*
 933                  * See if any signals need processing.
 934                  */
 935                 if (sigs)
 936                 {
 937                         psignals();
 938                         if (quitting)
 939                                 quit(QUIT_SAVED_STATUS);
 940                 }
 941
 942                 /*
 943                  * See if window size changed, for systems that don't
 944                  * generate SIGWINCH.
 945                  */
 946                 check_winch();
 947
 948                 /*
 949                  * Display prompt and accept a character.
 950                  */
 951                 cmd_reset();
 952                 prompt();
 953                 if (sigs)
 954                         continue;
 955                 if (newaction == A_NOACTION)
 956                         c = getcc();
 957
 958         again:
 959                 if (sigs)
 960                         continue;
 961
 962                 if (newaction != A_NOACTION)
 963                 {
 964                         action = newaction;
 965                         newaction = A_NOACTION;
 966                 } else
 967                 {
 968                         /*
 969                          * If we are in a multicharacter command, call mca_char.
 970                          * Otherwise we call fcmd_decode to determine the
 971                          * action to be performed.
 972                          */
 973                         if (mca)
 974                                 switch (mca_char(c))
 975                                 {
 976                                 case MCA_MORE:
 977                                         /*
 978                                          * Need another character.
 979                                          */
 980                                         c = getcc();
 981                                         goto again;
 982                                 case MCA_DONE:
 983                                         /*
 984                                          * Command has been handled by mca_char.
 985                                          * Start clean with a prompt.
 986                                          */
 987                                         continue;
 988                                 case NO_MCA:
 989                                         /*
 990                                          * Not a multi-char command
 991                                          * (at least, not anymore).
 992                                          */
 993                                         break;
 994                                 }
 995
 996                         /*
 997                          * Decode the command character and decide what to do.
 998                          */
 999                         if (mca)
1000                         {
1001                                 /*
1002                                  * We're in a multichar command.
1003                                  * Add the character to the command buffer
1004                                  * and display it on the screen.
1005                                  * If the user backspaces past the start
1006                                  * of the line, abort the command.
1007                                  */
1008                                 if (cmd_char(c) == CC_QUIT || len_cmdbuf() == 0)
1009                                         continue;
1010                                 cbuf = get_cmdbuf();
1011                         } else
1012                         {
1013                                 /*
1014                                  * Don't use cmd_char if we're starting fresh
1015                                  * at the beginning of a command, because we
1016                                  * don't want to echo the command until we know
1017                                  * it is a multichar command.  We also don't
1018                                  * want erase_char/kill_char to be treated
1019                                  * as line editing characters.
1020                                  */
1021                                 tbuf[0] = c;
1022                                 tbuf[1] = '\0';
1023                                 cbuf = tbuf;
1024                         }
1025                         extra = NULL;
1026                         action = fcmd_decode(cbuf, &extra);
1027                         /*
1028                          * If an "extra" string was returned,
1029                          * process it as a string of command characters.
1030                          */
1031                         if (extra != NULL)
1032                                 ungetsc(extra);
1033                 }
1034                 /*
1035                  * Clear the cmdbuf string.
1036                  * (But not if we're in the prefix of a command,
1037                  * because the partial command string is kept there.)
1038                  */
1039                 if (action != A_PREFIX)
1040                         cmd_reset();
1041
1042                 switch (action)
1043                 {
1044                 case A_DIGIT:
1045                         /*
1046                          * First digit of a number.
1047                          */
1048                         start_mca(A_DIGIT, ":", (void*)NULL, CF_QUIT_ON_ERASE);
1049                         goto again;
1050
1051                 case A_F_WINDOW:
1052                         /*
1053                          * Forward one window (and set the window size).
1054                          */
1055                         if (number > 0)
1056                                 swindow = (int) number;
1057                         /* FALLTHRU */
1058                 case A_F_SCREEN:
1059                         /*
1060                          * Forward one screen.
1061                          */
1062                         if (number <= 0)
1063                                 number = get_swindow();
1064                         cmd_exec();
1065                         if (show_attn)
1066                                 set_attnpos(bottompos);
1067                         forward((int) number, 0, 1);
1068                         break;
1069
1070                 case A_B_WINDOW:
1071                         /*
1072                          * Backward one window (and set the window size).
1073                          */
1074                         if (number > 0)
1075                                 swindow = (int) number;
1076                         /* FALLTHRU */
1077                 case A_B_SCREEN:
1078                         /*
1079                          * Backward one screen.
1080                          */
1081                         if (number <= 0)
1082                                 number = get_swindow();
1083                         cmd_exec();
1084                         backward((int) number, 0, 1);
1085                         break;
1086
1087                 case A_F_LINE:
1088                         /*
1089                          * Forward N (default 1) line.
1090                          */
1091                         if (number <= 0)
1092                                 number = 1;
1093                         cmd_exec();
1094                         if (show_attn == OPT_ONPLUS && number > 1)
1095                                 set_attnpos(bottompos);
1096                         forward((int) number, 0, 0);
1097                         break;
1098
1099                 case A_B_LINE:
1100                         /*
1101                          * Backward N (default 1) line.
1102                          */
1103                         if (number <= 0)
1104                                 number = 1;
1105                         cmd_exec();
1106                         backward((int) number, 0, 0);
1107                         break;
1108
1109                 case A_FF_LINE:
1110                         /*
1111                          * Force forward N (default 1) line.
1112                          */
1113                         if (number <= 0)
1114                                 number = 1;
1115                         cmd_exec();
1116                         if (show_attn == OPT_ONPLUS && number > 1)
1117                                 set_attnpos(bottompos);
1118                         forward((int) number, 1, 0);
1119                         break;
1120
1121                 case A_BF_LINE:
1122                         /*
1123                          * Force backward N (default 1) line.
1124                          */
1125                         if (number <= 0)
1126                                 number = 1;
1127                         cmd_exec();
1128                         backward((int) number, 1, 0);
1129                         break;
1130
1131                 case A_FF_SCREEN:
1132                         /*
1133                          * Force forward one screen.
1134                          */
1135                         if (number <= 0)
1136                                 number = get_swindow();
1137                         cmd_exec();
1138                         if (show_attn == OPT_ONPLUS)
1139                                 set_attnpos(bottompos);
1140                         forward((int) number, 1, 0);
1141                         break;
1142
1143                 case A_F_FOREVER:
1144                         /*
1145                          * Forward forever, ignoring EOF.
1146                          */
1147                         if (ch_getflags() & CH_HELPFILE)
1148                                 break;
1149                         cmd_exec();
1150                         jump_forw();
1151                         ignore_eoi = 1;
1152                         while (!sigs)
1153                         {
1154                                 make_display();
1155                                 forward(1, 0, 0);
1156                         }
1157                         ignore_eoi = 0;
1158                         /*
1159                          * This gets us back in "F mode" after processing
1160                          * a non-abort signal (e.g. window-change).
1161                          */
1162                         if (sigs && !ABORT_SIGS())
1163                                 newaction = A_F_FOREVER;
1164                         break;
1165
1166                 case A_F_SCROLL:
1167                         /*
1168                          * Forward N lines
1169                          * (default same as last 'd' or 'u' command).
1170                          */
1171                         if (number > 0)
1172                                 wscroll = (int) number;
1173                         cmd_exec();
1174                         if (show_attn == OPT_ONPLUS)
1175                                 set_attnpos(bottompos);
1176                         forward(wscroll, 0, 0);
1177                         break;
1178
1179                 case A_B_SCROLL:
1180                         /*
1181                          * Forward N lines
1182                          * (default same as last 'd' or 'u' command).
1183                          */
1184                         if (number > 0)
1185                                 wscroll = (int) number;
1186                         cmd_exec();
1187                         backward(wscroll, 0, 0);
1188                         break;
1189
1190                 case A_FREPAINT:
1191                         /*
1192                          * Flush buffers, then repaint screen.
1193                          * Don't flush the buffers on a pipe!
1194                          */
1195                         clear_buffers();
1196                         /* FALLTHRU */
1197                 case A_REPAINT:
1198                         /*
1199                          * Repaint screen.
1200                          */
1201                         cmd_exec();
1202                         repaint();
1203                         break;
1204
1205                 case A_GOLINE:
1206                         /*
1207                          * Go to line N, default beginning of file.
1208                          */
1209                         if (number <= 0)
1210                                 number = 1;
1211                         cmd_exec();
1212                         jump_back(number);
1213                         break;
1214
1215                 case A_PERCENT:
1216                         /*
1217                          * Go to a specified percentage into the file.
1218                          */
1219                         if (number < 0)
1220                         {
1221                                 number = 0;
1222                                 fraction = 0;
1223                         }
1224                         if (number > 100)
1225                         {
1226                                 number = 100;
1227                                 fraction = 0;
1228                         }
1229                         cmd_exec();
1230                         jump_percent((int) number, fraction);
1231                         break;
1232
1233                 case A_GOEND:
1234                         /*
1235                          * Go to line N, default end of file.
1236                          */
1237                         cmd_exec();
1238                         if (number <= 0)
1239                                 jump_forw();
1240                         else
1241                                 jump_back(number);
1242                         break;
1243
1244                 case A_GOPOS:
1245                         /*
1246                          * Go to a specified byte position in the file.
1247                          */
1248                         cmd_exec();
1249                         if (number < 0)
1250                                 number = 0;
1251                         jump_line_loc((POSITION) number, jump_sline);
1252                         break;
1253
1254                 case A_STAT:
1255                         /*
1256                          * Print file name, etc.
1257                          */
1258                         if (ch_getflags() & CH_HELPFILE)
1259                                 break;
1260                         cmd_exec();
1261                         parg.p_string = eq_message();
1262                         error("%s", &parg);
1263                         break;
1264
1265                 case A_VERSION:
1266                         /*
1267                          * Print version number, without the "@(#)".
1268                          */
1269                         cmd_exec();
1270                         dispversion();
1271                         break;
1272
1273                 case A_QUIT:
1274                         /*
1275                          * Exit.
1276                          */
1277                         if (curr_ifile != NULL_IFILE &&
1278                             ch_getflags() & CH_HELPFILE)
1279                         {
1280                                 /*
1281                                  * Quit while viewing the help file
1282                                  * just means return to viewing the
1283                                  * previous file.
1284                                  */
1285                                 hshift = save_hshift;
1286                                 if (edit_prev(1) == 0)
1287                                         break;
1288                         }
1289                         if (extra != NULL)
1290                                 quit(*extra);
1291                         quit(QUIT_OK);
1292                         break;
1293
1294 /*
1295  * Define abbreviation for a commonly used sequence below.
1296  */
1297 #define DO_SEARCH() \
1298                         if (number <= 0) number = 1;    \
1299                         mca_search();                   \
1300                         cmd_exec();                     \
1301                         multi_search((char *)NULL, (int) number);
1302
1303
1304                 case A_F_SEARCH:
1305                         /*
1306                          * Search forward for a pattern.
1307                          * Get the first char of the pattern.
1308                          */
1309                         search_type = SRCH_FORW;
1310                         if (number <= 0)
1311                                 number = 1;
1312                         mca_search();
1313                         c = getcc();
1314                         goto again;
1315
1316                 case A_B_SEARCH:
1317                         /*
1318                          * Search backward for a pattern.
1319                          * Get the first char of the pattern.
1320                          */
1321                         search_type = SRCH_BACK;
1322                         if (number <= 0)
1323                                 number = 1;
1324                         mca_search();
1325                         c = getcc();
1326                         goto again;
1327
1328                 case A_FILTER:
1329 #if HILITE_SEARCH
1330                         search_type = SRCH_FORW | SRCH_FILTER;
1331                         mca_search();
1332                         c = getcc();
1333                         goto again;
1334 #else
1335                         error("Command not available", NULL_PARG);
1336                         break;
1337 #endif
1338
1339                 case A_AGAIN_SEARCH:
1340                         /*
1341                          * Repeat previous search.
1342                          */
1343                         DO_SEARCH();
1344                         break;
1345
1346                 case A_T_AGAIN_SEARCH:
1347                         /*
1348                          * Repeat previous search, multiple files.
1349                          */
1350                         search_type |= SRCH_PAST_EOF;
1351                         DO_SEARCH();
1352                         break;
1353
1354                 case A_REVERSE_SEARCH:
1355                         /*
1356                          * Repeat previous search, in reverse direction.
1357                          */
1358                         save_search_type = search_type;
1359                         search_type = SRCH_REVERSE(search_type);
1360                         DO_SEARCH();
1361                         search_type = save_search_type;
1362                         break;
1363
1364                 case A_T_REVERSE_SEARCH:
1365                         /*
1366                          * Repeat previous search,
1367                          * multiple files in reverse direction.
1368                          */
1369                         save_search_type = search_type;
1370                         search_type = SRCH_REVERSE(search_type);
1371                         search_type |= SRCH_PAST_EOF;
1372                         DO_SEARCH();
1373                         search_type = save_search_type;
1374                         break;
1375
1376                 case A_UNDO_SEARCH:
1377                         undo_search();
1378                         break;
1379
1380                 case A_HELP:
1381                         /*
1382                          * Help.
1383                          */
1384                         if (ch_getflags() & CH_HELPFILE)
1385                                 break;
1386                         cmd_exec();
1387                         save_hshift = hshift;
1388                         hshift = 0;
1389                         (void) edit(FAKE_HELPFILE);
1390                         break;
1391
1392                 case A_EXAMINE:
1393 #if EXAMINE
1394                         /*
1395                          * Edit a new file.  Get the filename.
1396                          */
1397                         if (secure)
1398                         {
1399                                 error("Command not available", NULL_PARG);
1400                                 break;
1401                         }
1402                         start_mca(A_EXAMINE, "Examine: ", ml_examine, 0);
1403                         c = getcc();
1404                         goto again;
1405 #else
1406                         error("Command not available", NULL_PARG);
1407                         break;
1408 #endif
1409
1410                 case A_VISUAL:
1411                         /*
1412                          * Invoke an editor on the input file.
1413                          */
1414 #if EDITOR
1415                         if (secure)
1416                         {
1417                                 error("Command not available", NULL_PARG);
1418                                 break;
1419                         }
1420                         if (ch_getflags() & CH_HELPFILE)
1421                                 break;
1422                         if (strcmp(get_filename(curr_ifile), "-") == 0)
1423                         {
1424                                 error("Cannot edit standard input", NULL_PARG);
1425                                 break;
1426                         }
1427                         if (curr_altfilename != NULL)
1428                         {
1429                                 error("WARNING: This file was viewed via LESSOPEN",
1430                                         NULL_PARG);
1431                         }
1432                         start_mca(A_SHELL, "!", ml_shell, 0);
1433                         /*
1434                          * Expand the editor prototype string
1435                          * and pass it to the system to execute.
1436                          * (Make sure the screen is displayed so the
1437                          * expansion of "+%lm" works.)
1438                          */
1439                         make_display();
1440                         cmd_exec();
1441                         lsystem(pr_expand(editproto, 0), (char*)NULL);
1442                         break;
1443 #else
1444                         error("Command not available", NULL_PARG);
1445                         break;
1446 #endif
1447
1448                 case A_NEXT_FILE:
1449                         /*
1450                          * Examine next file.
1451                          */
1452 #if TAGS
1453                         if (ntags())
1454                         {
1455                                 error("No next file", NULL_PARG);
1456                                 break;
1457                         }
1458 #endif
1459                         if (number <= 0)
1460                                 number = 1;
1461                         if (edit_next((int) number))
1462                         {
1463                                 if (get_quit_at_eof() && eof_displayed() &&
1464                                     !(ch_getflags() & CH_HELPFILE))
1465                                         quit(QUIT_OK);
1466                                 parg.p_string = (number > 1) ? "(N-th) " : "";
1467                                 error("No %snext file", &parg);
1468                         }
1469                         break;
1470
1471                 case A_PREV_FILE:
1472                         /*
1473                          * Examine previous file.
1474                          */
1475 #if TAGS
1476                         if (ntags())
1477                         {
1478                                 error("No previous file", NULL_PARG);
1479                                 break;
1480                         }
1481 #endif
1482                         if (number <= 0)
1483                                 number = 1;
1484                         if (edit_prev((int) number))
1485                         {
1486                                 parg.p_string = (number > 1) ? "(N-th) " : "";
1487                                 error("No %sprevious file", &parg);
1488                         }
1489                         break;
1490
1491                 case A_NEXT_TAG:
1492 #if TAGS
1493                         if (number <= 0)
1494                                 number = 1;
1495                         tagfile = nexttag((int) number);
1496                         if (tagfile == NULL)
1497                         {
1498                                 error("No next tag", NULL_PARG);
1499                                 break;
1500                         }
1501                         if (edit(tagfile) == 0)
1502                         {
1503                                 POSITION pos = tagsearch();
1504                                 if (pos != NULL_POSITION)
1505                                         jump_loc(pos, jump_sline);
1506                         }
1507 #else
1508                         error("Command not available", NULL_PARG);
1509 #endif
1510                         break;
1511
1512                 case A_PREV_TAG:
1513 #if TAGS
1514                         if (number <= 0)
1515                                 number = 1;
1516                         tagfile = prevtag((int) number);
1517                         if (tagfile == NULL)
1518                         {
1519                                 error("No previous tag", NULL_PARG);
1520                                 break;
1521                         }
1522                         if (edit(tagfile) == 0)
1523                         {
1524                                 POSITION pos = tagsearch();
1525                                 if (pos != NULL_POSITION)
1526                                         jump_loc(pos, jump_sline);
1527                         }
1528 #else
1529                         error("Command not available", NULL_PARG);
1530 #endif
1531                         break;
1532
1533                 case A_INDEX_FILE:
1534                         /*
1535                          * Examine a particular file.
1536                          */
1537                         if (number <= 0)
1538                                 number = 1;
1539                         if (edit_index((int) number))
1540                                 error("No such file", NULL_PARG);
1541                         break;
1542
1543                 case A_REMOVE_FILE:
1544                         if (ch_getflags() & CH_HELPFILE)
1545                                 break;
1546                         old_ifile = curr_ifile;
1547                         new_ifile = getoff_ifile(curr_ifile);
1548                         if (new_ifile == NULL_IFILE)
1549                         {
1550                                 bell();
1551                                 break;
1552                         }
1553                         if (edit_ifile(new_ifile) != 0)
1554                         {
1555                                 reedit_ifile(old_ifile);
1556                                 break;
1557                         }
1558                         del_ifile(old_ifile);
1559                         break;
1560
1561                 case A_OPT_TOGGLE:
1562                         optflag = OPT_TOGGLE;
1563                         optgetname = FALSE;
1564                         mca_opt_toggle();
1565                         c = getcc();
1566                         goto again;
1567
1568                 case A_DISP_OPTION:
1569                         /*
1570                          * Report a flag setting.
1571                          */
1572                         optflag = OPT_NO_TOGGLE;
1573                         optgetname = FALSE;
1574                         mca_opt_toggle();
1575                         c = getcc();
1576                         goto again;
1577
1578                 case A_FIRSTCMD:
1579                         /*
1580                          * Set an initial command for new files.
1581                          */
1582                         start_mca(A_FIRSTCMD, "+", (void*)NULL, 0);
1583                         c = getcc();
1584                         goto again;
1585
1586                 case A_SHELL:
1587                         /*
1588                          * Shell escape.
1589                          */
1590 #if SHELL_ESCAPE
1591                         if (secure)
1592                         {
1593                                 error("Command not available", NULL_PARG);
1594                                 break;
1595                         }
1596                         start_mca(A_SHELL, "!", ml_shell, 0);
1597                         c = getcc();
1598                         goto again;
1599 #else
1600                         error("Command not available", NULL_PARG);
1601                         break;
1602 #endif
1603
1604                 case A_SETMARK:
1605                         /*
1606                          * Set a mark.
1607                          */
1608                         if (ch_getflags() & CH_HELPFILE)
1609                                 break;
1610                         start_mca(A_SETMARK, "mark: ", (void*)NULL, 0);
1611                         c = getcc();
1612                         if (c == erase_char || c == erase2_char ||
1613                             c == kill_char || c == '\n' || c == '\r')
1614                                 break;
1615                         setmark(c);
1616                         break;
1617
1618                 case A_GOMARK:
1619                         /*
1620                          * Go to a mark.
1621                          */
1622                         start_mca(A_GOMARK, "goto mark: ", (void*)NULL, 0);
1623                         c = getcc();
1624                         if (c == erase_char || c == erase2_char ||
1625                             c == kill_char || c == '\n' || c == '\r')
1626                                 break;
1627                         cmd_exec();
1628                         gomark(c);
1629                         break;
1630
1631                 case A_PIPE:
1632 #if PIPEC
1633                         if (secure)
1634                         {
1635                                 error("Command not available", NULL_PARG);
1636                                 break;
1637                         }
1638                         start_mca(A_PIPE, "|mark: ", (void*)NULL, 0);
1639                         c = getcc();
1640                         if (c == erase_char || c == erase2_char || c == kill_char)
1641                                 break;
1642                         if (c == '\n' || c == '\r')
1643                                 c = '.';
1644                         if (badmark(c))
1645                                 break;
1646                         pipec = c;
1647                         start_mca(A_PIPE, "!", ml_shell, 0);
1648                         c = getcc();
1649                         goto again;
1650 #else
1651                         error("Command not available", NULL_PARG);
1652                         break;
1653 #endif
1654
1655                 case A_B_BRACKET:
1656                 case A_F_BRACKET:
1657                         start_mca(action, "Brackets: ", (void*)NULL, 0);
1658                         c = getcc();
1659                         goto again;
1660
1661                 case A_LSHIFT:
1662                         if (number > 0)
1663                                 shift_count = number;
1664                         else
1665                                 number = (shift_count > 0) ?
1666                                         shift_count : sc_width / 2;
1667                         if (number > hshift)
1668                                 number = hshift;
1669                         hshift -= number;
1670                         screen_trashed = 1;
1671                         break;
1672
1673                 case A_RSHIFT:
1674                         if (number > 0)
1675                                 shift_count = number;
1676                         else
1677                                 number = (shift_count > 0) ?
1678                                         shift_count : sc_width / 2;
1679                         hshift += number;
1680                         screen_trashed = 1;
1681                         break;
1682
1683                 case A_PREFIX:
1684                         /*
1685                          * The command is incomplete (more chars are needed).
1686                          * Display the current char, so the user knows
1687                          * what's going on, and get another character.
1688                          */
1689                         if (mca != A_PREFIX)
1690                         {
1691                                 cmd_reset();
1692                                 start_mca(A_PREFIX, " ", (void*)NULL,
1693                                         CF_QUIT_ON_ERASE);
1694                                 (void) cmd_char(c);
1695                         }
1696                         c = getcc();
1697                         goto again;
1698
1699                 case A_NOACTION:
1700                         break;
1701
1702                 default:
1703                         bell();
1704                         break;
1705                 }
1706         }
1707 }