cl/cl_screen.c

   1 /*-
   2  * Copyright (c) 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1993, 1994, 1995, 1996
   5  *      Keith Bostic.  All rights reserved.
   6  *
   7  * See the LICENSE file for redistribution information.
   8  */
   9
  10 #include "config.h"
  11
  12 #ifndef lint
  13 static const char sccsid[] = "$Id: cl_screen.c,v 10.53 2000/07/23 11:14:45 skimo Exp $ (Berkeley) $Date: 2000/07/23 11:14:45 $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18
  19 #include <bitstring.h>
  20 #include <errno.h>
  21 #include <signal.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <termios.h>
  26 #include <unistd.h>
  27
  28 #include "../common/common.h"
  29 #include "cl.h"
  30
  31 static int      cl_ex_end __P((GS *));
  32 static int      cl_ex_init __P((SCR *));
  33 static void     cl_freecap __P((CL_PRIVATE *));
  34 static int      cl_vi_end __P((GS *));
  35 static int      cl_vi_init __P((SCR *));
  36 static int      cl_putenv __P((char *, char *, u_long));
  37
  38 /*
  39  * cl_screen --
  40  *      Switch screen types.
  41  *
  42  * PUBLIC: int cl_screen __P((SCR *, u_int32_t));
  43  */
  44 int
  45 cl_screen(sp, flags)
  46         SCR *sp;
  47         u_int32_t flags;
  48 {
  49         CL_PRIVATE *clp;
  50         WINDOW *win;
  51         GS *gp;
  52
  53         gp = sp->gp;
  54         clp = CLP(sp);
  55         win = CLSP(sp) ? CLSP(sp) : stdscr;
  56
  57         /* See if the current information is incorrect. */
  58         if (F_ISSET(gp, G_SRESTART)) {
  59                 if (CLSP(sp)) {
  60                     delwin(CLSP(sp));
  61                     CLSP(sp) = NULL;
  62                 }
  63                 if (cl_quit(gp))
  64                         return (1);
  65                 F_CLR(gp, G_SRESTART);
  66         }
  67
  68         /* See if we're already in the right mode. */
  69         if (LF_ISSET(SC_EX) && F_ISSET(sp, SC_SCR_EX) ||
  70             LF_ISSET(SC_VI) && F_ISSET(sp, SC_SCR_VI))
  71                 return (0);
  72
  73         /*
  74          * Fake leaving ex mode.
  75          *
  76          * We don't actually exit ex or vi mode unless forced (e.g. by a window
  77          * size change).  This is because many curses implementations can't be
  78          * called twice in a single program.  Plus, it's faster.  If the editor
  79          * "leaves" vi to enter ex, when it exits ex we'll just fall back into
  80          * vi.
  81          */
  82         if (F_ISSET(sp, SC_SCR_EX))
  83                 F_CLR(sp, SC_SCR_EX);
  84
  85         /*
  86          * Fake leaving vi mode.
  87          *
  88          * Clear out the rest of the screen if we're in the middle of a split
  89          * screen.  Move to the last line in the current screen -- this makes
  90          * terminal scrolling happen naturally.  Note: *don't* move past the
  91          * end of the screen, as there are ex commands (e.g., :read ! cat file)
  92          * that don't want to.  Don't clear the info line, its contents may be
  93          * valid, e.g. :file|append.
  94          */
  95         if (F_ISSET(sp, SC_SCR_VI)) {
  96                 F_CLR(sp, SC_SCR_VI);
  97
  98                 if (sp->q.cqe_next != (void *)&sp->wp->scrq) {
  99                         (void)wmove(win, RLNO(sp, sp->rows), 0);
 100                         wclrtobot(win);
 101                 }
 102                 (void)wmove(win, RLNO(sp, sp->rows) - 1, 0);
 103                 wrefresh(win);
 104         }
 105
 106         /* Enter the requested mode. */
 107         if (LF_ISSET(SC_EX)) {
 108                 if (cl_ex_init(sp))
 109                         return (1);
 110                 F_SET(clp, CL_IN_EX | CL_SCR_EX_INIT);
 111
 112                 /*
 113                  * If doing an ex screen for ex mode, move to the last line
 114                  * on the screen.
 115                  */
 116                 if (F_ISSET(sp, SC_EX) && clp->cup != NULL)
 117                         tputs(tgoto(clp->cup,
 118                             0, O_VAL(sp, O_LINES) - 1), 1, cl_putchar);
 119         } else {
 120                 if (cl_vi_init(sp))
 121                         return (1);
 122                 F_CLR(clp, CL_IN_EX);
 123                 F_SET(clp, CL_SCR_VI_INIT);
 124         }
 125         return (0);
 126 }
 127
 128 /*
 129  * cl_quit --
 130  *      Shutdown the screens.
 131  *
 132  * PUBLIC: int cl_quit __P((GS *));
 133  */
 134 int
 135 cl_quit(gp)
 136         GS *gp;
 137 {
 138         CL_PRIVATE *clp;
 139         int rval;
 140
 141         rval = 0;
 142         clp = GCLP(gp);
 143
 144         /*
 145          * If we weren't really running, ignore it.  This happens if the
 146          * screen changes size before we've called curses.
 147          */
 148         if (!F_ISSET(clp, CL_SCR_EX_INIT | CL_SCR_VI_INIT))
 149                 return (0);
 150
 151         /* Clean up the terminal mappings. */
 152         if (cl_term_end(gp))
 153                 rval = 1;
 154
 155         /* Really leave vi mode. */
 156         if (F_ISSET(clp, CL_STDIN_TTY) &&
 157             F_ISSET(clp, CL_SCR_VI_INIT) && cl_vi_end(gp))
 158                 rval = 1;
 159
 160         /* Really leave ex mode. */
 161         if (F_ISSET(clp, CL_STDIN_TTY) &&
 162             F_ISSET(clp, CL_SCR_EX_INIT) && cl_ex_end(gp))
 163                 rval = 1;
 164
 165         /*
 166          * If we were running ex when we quit, or we're using an implementation
 167          * of curses where endwin() doesn't get this right, restore the original
 168          * terminal modes.
 169          *
 170          * XXX
 171          * We always do this because it's too hard to figure out what curses
 172          * implementations get it wrong.  It may discard type-ahead characters
 173          * from the tty queue.
 174          */
 175         (void)tcsetattr(STDIN_FILENO, TCSADRAIN | TCSASOFT, &clp->orig);
 176
 177         F_CLR(clp, CL_SCR_EX_INIT | CL_SCR_VI_INIT);
 178         return (rval);
 179 }
 180
 181 /*
 182  * cl_vi_init --
 183  *      Initialize the curses vi screen.
 184  */
 185 static int
 186 cl_vi_init(sp)
 187         SCR *sp;
 188 {
 189         CL_PRIVATE *clp;
 190         GS *gp;
 191         char *o_cols, *o_lines, *o_term, *ttype;
 192
 193         gp = sp->gp;
 194         clp = CLP(sp);
 195
 196         /* If already initialized, just set the terminal modes. */
 197         if (F_ISSET(clp, CL_SCR_VI_INIT))
 198                 goto fast;
 199
 200         /* Curses vi always reads from (and writes to) a terminal. */
 201         if (!F_ISSET(clp, CL_STDIN_TTY) || !isatty(STDOUT_FILENO)) {
 202                 msgq(sp, M_ERR,
 203                     "016|Vi's standard input and output must be a terminal");
 204                 return (1);
 205         }
 206
 207         /* We'll need a terminal type. */
 208         if (opts_empty(sp, O_TERM, 0))
 209                 return (1);
 210         ttype = O_STR(sp, O_TERM);
 211
 212         /*
 213          * XXX
 214          * Changing the row/column and terminal values is done by putting them
 215          * into the environment, which is then read by curses.  What this loses
 216          * in ugliness, it makes up for in stupidity.  We can't simply put the
 217          * values into the environment ourselves, because in the presence of a
 218          * kernel mechanism for returning the window size, entering values into
 219          * the environment will screw up future screen resizing events, e.g. if
 220          * the user enters a :shell command and then resizes their window.  So,
 221          * if they weren't already in the environment, we make sure to delete
 222          * them immediately after setting them.
 223          *
 224          * XXX
 225          * Putting the TERM variable into the environment is necessary, even
 226          * though we're using newterm() here.  We may be using initscr() as
 227          * the underlying function.
 228          */
 229         o_term = getenv("TERM");
 230         cl_putenv("TERM", ttype, 0);
 231         o_lines = getenv("LINES");
 232         cl_putenv("LINES", NULL, (u_long)O_VAL(sp, O_LINES));
 233         o_cols = getenv("COLUMNS");
 234         cl_putenv("COLUMNS", NULL, (u_long)O_VAL(sp, O_COLUMNS));
 235
 236         /*
 237          * We don't care about the SCREEN reference returned by newterm, we
 238          * never have more than one SCREEN at a time.
 239          *
 240          * XXX
 241          * The SunOS initscr() can't be called twice.  Don't even think about
 242          * using it.  It fails in subtle ways (e.g. select(2) on fileno(stdin)
 243          * stops working).  (The SVID notes that applications should only call
 244          * initscr() once.)
 245          *
 246          * XXX
 247          * The HP/UX newterm doesn't support the NULL first argument, so we
 248          * have to specify the terminal type.
 249          */
 250         errno = 0;
 251         if (newterm(ttype, stdout, stdin) == NULL) {
 252                 if (errno)
 253                         msgq(sp, M_SYSERR, "%s", ttype);
 254                 else
 255                         msgq(sp, M_ERR, "%s: unknown terminal type", ttype);
 256                 return (1);
 257         }
 258
 259         if (o_term == NULL)
 260                 unsetenv("TERM");
 261         if (o_lines == NULL)
 262                 unsetenv("LINES");
 263         if (o_cols == NULL)
 264                 unsetenv("COLUMNS");
 265
 266         /*
 267          * XXX
 268          * Someone got let out alone without adult supervision -- the SunOS
 269          * newterm resets the signal handlers.  There's a race, but it's not
 270          * worth closing.
 271          */
 272         (void)sig_init(sp->gp, sp);
 273
 274         /*
 275          * We use raw mode.  What we want is 8-bit clean, however, signals
 276          * and flow control should continue to work.  Admittedly, it sounds
 277          * like cbreak, but it isn't.  Using cbreak() can get you additional
 278          * things like IEXTEN, which turns on flags like DISCARD and LNEXT.
 279          *
 280          * !!!
 281          * If raw isn't turning off echo and newlines, something's wrong.
 282          * However, it shouldn't hurt.
 283          */
 284         noecho();                       /* No character echo. */
 285         nonl();                         /* No CR/NL translation. */
 286         raw();                          /* 8-bit clean. */
 287         idlok(stdscr, 1);               /* Use hardware insert/delete line. */
 288
 289         /* Put the cursor keys into application mode. */
 290         (void)keypad(stdscr, TRUE);
 291
 292         /*
 293          * XXX
 294          * The screen TI sequence just got sent.  See the comment in
 295          * cl_funcs.c:cl_attr().
 296          */
 297         clp->ti_te = TI_SENT;
 298
 299         /*
 300          * XXX
 301          * Historic implementations of curses handled SIGTSTP signals
 302          * in one of three ways.  They either:
 303          *
 304          *      1: Set their own handler, regardless.
 305          *      2: Did not set a handler if a handler was already installed.
 306          *      3: Set their own handler, but then called any previously set
 307          *         handler after completing their own cleanup.
 308          *
 309          * We don't try and figure out which behavior is in place, we force
 310          * it to SIG_DFL after initializing the curses interface, which means
 311          * that curses isn't going to take the signal.  Since curses isn't
 312          * reentrant (i.e., the whole curses SIGTSTP interface is a fantasy),
 313          * we're doing The Right Thing.
 314          */
 315         (void)signal(SIGTSTP, SIG_DFL);
 316
 317         /*
 318          * If flow control was on, turn it back on.  Turn signals on.  ISIG
 319          * turns on VINTR, VQUIT, VDSUSP and VSUSP.   The main curses code
 320          * already installed a handler for VINTR.  We're going to disable the
 321          * other three.
 322          *
 323          * XXX
 324          * We want to use ^Y as a vi scrolling command.  If the user has the
 325          * DSUSP character set to ^Y (common practice) clean it up.  As it's
 326          * equally possible that the user has VDSUSP set to 'a', we disable
 327          * it regardless.  It doesn't make much sense to suspend vi at read,
 328          * so I don't think anyone will care.  Alternatively, we could look
 329          * it up in the table of legal command characters and turn it off if
 330          * it matches one.  VDSUSP wasn't in POSIX 1003.1-1990, so we test for
 331          * it.
 332          *
 333          * XXX
 334          * We don't check to see if the user had signals enabled originally.
 335          * If they didn't, it's unclear what we're supposed to do here, but
 336          * it's also pretty unlikely.
 337          */
 338         if (tcgetattr(STDIN_FILENO, &clp->vi_enter)) {
 339                 msgq(sp, M_SYSERR, "tcgetattr");
 340                 goto err;
 341         }
 342         if (clp->orig.c_iflag & IXON)
 343                 clp->vi_enter.c_iflag |= IXON;
 344         if (clp->orig.c_iflag & IXOFF)
 345                 clp->vi_enter.c_iflag |= IXOFF;
 346
 347         clp->vi_enter.c_lflag |= ISIG;
 348 #ifdef VDSUSP
 349         clp->vi_enter.c_cc[VDSUSP] = _POSIX_VDISABLE;
 350 #endif
 351         clp->vi_enter.c_cc[VQUIT] = _POSIX_VDISABLE;
 352         clp->vi_enter.c_cc[VSUSP] = _POSIX_VDISABLE;
 353
 354         /*
 355          * XXX
 356          * OSF/1 doesn't turn off the <discard>, <literal-next> or <status>
 357          * characters when curses switches into raw mode.  It should be OK
 358          * to do it explicitly for everyone.
 359          */
 360 #ifdef VDISCARD
 361         clp->vi_enter.c_cc[VDISCARD] = _POSIX_VDISABLE;
 362 #endif
 363 #ifdef VLNEXT
 364         clp->vi_enter.c_cc[VLNEXT] = _POSIX_VDISABLE;
 365 #endif
 366 #ifdef VSTATUS
 367         clp->vi_enter.c_cc[VSTATUS] = _POSIX_VDISABLE;
 368 #endif
 369
 370         /* Initialize terminal based information. */
 371         if (cl_term_init(sp))
 372                 goto err;
 373
 374 fast:   /* Set the terminal modes. */
 375         if (tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &clp->vi_enter)) {
 376                 msgq(sp, M_SYSERR, "tcsetattr");
 377 err:            (void)cl_vi_end(sp->gp);
 378                 return (1);
 379         }
 380         return (0);
 381 }
 382
 383 /*
 384  * cl_vi_end --
 385  *      Shutdown the vi screen.
 386  */
 387 static int
 388 cl_vi_end(gp)
 389         GS *gp;
 390 {
 391         CL_PRIVATE *clp;
 392
 393         clp = GCLP(gp);
 394
 395         /* Restore the cursor keys to normal mode. */
 396         (void)keypad(stdscr, FALSE);
 397
 398         /*
 399          * If we were running vi when we quit, scroll the screen up a single
 400          * line so we don't lose any information.
 401          *
 402          * Move to the bottom of the window (some endwin implementations don't
 403          * do this for you).
 404          */
 405         if (!F_ISSET(clp, CL_IN_EX)) {
 406                 (void)move(0, 0);
 407                 (void)deleteln();
 408                 (void)move(LINES - 1, 0);
 409                 (void)refresh();
 410         }
 411
 412         cl_freecap(clp);
 413
 414         /* End curses window. */
 415         (void)endwin();
 416
 417         /*
 418          * XXX
 419          * The screen TE sequence just got sent.  See the comment in
 420          * cl_funcs.c:cl_attr().
 421          */
 422         clp->ti_te = TE_SENT;
 423
 424         return (0);
 425 }
 426
 427 /*
 428  * cl_ex_init --
 429  *      Initialize the ex screen.
 430  */
 431 static int
 432 cl_ex_init(sp)
 433         SCR *sp;
 434 {
 435         CL_PRIVATE *clp;
 436
 437         clp = CLP(sp);
 438
 439         /* If already initialized, just set the terminal modes. */
 440         if (F_ISSET(clp, CL_SCR_EX_INIT))
 441                 goto fast;
 442
 443         /* If not reading from a file, we're done. */
 444         if (!F_ISSET(clp, CL_STDIN_TTY))
 445                 return (0);
 446
 447         /* Get the ex termcap/terminfo strings. */
 448         (void)cl_getcap(sp, "cup", &clp->cup);
 449         (void)cl_getcap(sp, "smso", &clp->smso);
 450         (void)cl_getcap(sp, "rmso", &clp->rmso);
 451         (void)cl_getcap(sp, "el", &clp->el);
 452         (void)cl_getcap(sp, "cuu1", &clp->cuu1);
 453
 454         /* Enter_standout_mode and exit_standout_mode are paired. */
 455         if (clp->smso == NULL || clp->rmso == NULL) {
 456                 if (clp->smso != NULL) {
 457                         free(clp->smso);
 458                         clp->smso = NULL;
 459                 }
 460                 if (clp->rmso != NULL) {
 461                         free(clp->rmso);
 462                         clp->rmso = NULL;
 463                 }
 464         }
 465
 466         /*
 467          * Turn on canonical mode, with normal input and output processing.
 468          * Start with the original terminal settings as the user probably
 469          * had them (including any local extensions) set correctly for the
 470          * current terminal.
 471          *
 472          * !!!
 473          * We can't get everything that we need portably; for example, ONLCR,
 474          * mapping <newline> to <carriage-return> on output isn't required
 475          * by POSIX 1003.1b-1993.  If this turns out to be a problem, then
 476          * we'll either have to play some games on the mapping, or we'll have
 477          * to make all ex printf's output \r\n instead of \n.
 478          */
 479         clp->ex_enter = clp->orig;
 480         clp->ex_enter.c_lflag  |= ECHO | ECHOE | ECHOK | ICANON | IEXTEN | ISIG;
 481 #ifdef ECHOCTL
 482         clp->ex_enter.c_lflag |= ECHOCTL;
 483 #endif
 484 #ifdef ECHOKE
 485         clp->ex_enter.c_lflag |= ECHOKE;
 486 #endif
 487         clp->ex_enter.c_iflag |= ICRNL;
 488         clp->ex_enter.c_oflag |= OPOST;
 489 #ifdef ONLCR
 490         clp->ex_enter.c_oflag |= ONLCR;
 491 #endif
 492
 493 fast:   if (tcsetattr(STDIN_FILENO, TCSADRAIN | TCSASOFT, &clp->ex_enter)) {
 494                 msgq(sp, M_SYSERR, "tcsetattr");
 495                 return (1);
 496         }
 497         return (0);
 498 }
 499
 500 /*
 501  * cl_ex_end --
 502  *      Shutdown the ex screen.
 503  */
 504 static int
 505 cl_ex_end(gp)
 506         GS *gp;
 507 {
 508         CL_PRIVATE *clp;
 509
 510         clp = GCLP(gp);
 511
 512         cl_freecap(clp);
 513
 514         return (0);
 515 }
 516
 517 /*
 518  * cl_getcap --
 519  *      Retrieve termcap/terminfo strings.
 520  *
 521  * PUBLIC: int cl_getcap __P((SCR *, char *, char **));
 522  */
 523 int
 524 cl_getcap(sp, name, elementp)
 525         SCR *sp;
 526         char *name, **elementp;
 527 {
 528         size_t len;
 529         char *t;
 530
 531         if ((t = tigetstr(name)) != NULL &&
 532             t != (char *)-1 && (len = strlen(t)) != 0) {
 533                 MALLOC_RET(sp, *elementp, char *, len + 1);
 534                 memmove(*elementp, t, len + 1);
 535         }
 536         return (0);
 537 }
 538
 539 /*
 540  * cl_freecap --
 541  *      Free any allocated termcap/terminfo strings.
 542  */
 543 static void
 544 cl_freecap(clp)
 545         CL_PRIVATE *clp;
 546 {
 547         if (clp->el != NULL) {
 548                 free(clp->el);
 549                 clp->el = NULL;
 550         }
 551         if (clp->cup != NULL) {
 552                 free(clp->cup);
 553                 clp->cup = NULL;
 554         }
 555         if (clp->cuu1 != NULL) {
 556                 free(clp->cuu1);
 557                 clp->cuu1 = NULL;
 558         }
 559         if (clp->rmso != NULL) {
 560                 free(clp->rmso);
 561                 clp->rmso = NULL;
 562         }
 563         if (clp->smso != NULL) {
 564                 free(clp->smso);
 565                 clp->smso = NULL;
 566         }
 567 }
 568
 569 /*
 570  * cl_putenv --
 571  *      Put a value into the environment.
 572  */
 573 static int
 574 cl_putenv(name, str, value)
 575         char *name, *str;
 576         u_long value;
 577
 578 {
 579         char buf[40];
 580
 581         if (str == NULL) {
 582                 (void)snprintf(buf, sizeof(buf), "%lu", value);
 583                 return (setenv(name, buf, 1));
 584         } else
 585                 return (setenv(name, str, 1));
 586 }