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 10.51 2000/06/25 17:34:36 skimo Exp $ (Berkeley) $Date: 2000/06/25 17:34:36 $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18
  19 #include <bitstring.h>
  20 #include <curses.h>
  21 #include <errno.h>
  22 #include <signal.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <termios.h>
  27 #include <unistd.h>
  28
  29 #include "../common/common.h"
  30 #include "cl.h"
  31
  32 static int      cl_ex_end __P((GS *));
  33 static int      cl_ex_init __P((SCR *));
  34 static void     cl_freecap __P((CL_PRIVATE *));
  35 static int      cl_vi_end __P((GS *));
  36 static int      cl_vi_init __P((SCR *));
  37 static int      cl_putenv __P((char *, char *, u_long));
  38
  39 /*
  40  * cl_screen --
  41  *      Switch screen types.
  42  *
  43  * PUBLIC: int cl_screen __P((SCR *, u_int32_t));
  44  */
  45 int
  46 cl_screen(sp, flags)
  47         SCR *sp;
  48         u_int32_t flags;
  49 {
  50         CL_PRIVATE *clp;
  51         WINDOW *win;
  52         GS *gp;
  53
  54         gp = sp->gp;
  55         clp = CLP(sp);
  56         win = CLSP(sp) ? CLSP(sp) : stdscr;
  57
  58         /* See if the current information is incorrect. */
  59         if (F_ISSET(gp, G_SRESTART)) {
  60                 if (cl_quit(gp))
  61                         return (1);
  62                 F_CLR(gp, G_SRESTART);
  63         }
  64
  65         /* See if we're already in the right mode. */
  66         if (LF_ISSET(SC_EX) && F_ISSET(sp, SC_SCR_EX) ||
  67             LF_ISSET(SC_VI) && F_ISSET(sp, SC_SCR_VI))
  68                 return (0);
  69
  70         /*
  71          * Fake leaving ex mode.
  72          *
  73          * We don't actually exit ex or vi mode unless forced (e.g. by a window
  74          * size change).  This is because many curses implementations can't be
  75          * called twice in a single program.  Plus, it's faster.  If the editor
  76          * "leaves" vi to enter ex, when it exits ex we'll just fall back into
  77          * vi.
  78          */
  79         if (F_ISSET(sp, SC_SCR_EX))
  80                 F_CLR(sp, SC_SCR_EX);
  81
  82         /*
  83          * Fake leaving vi mode.
  84          *
  85          * Clear out the rest of the screen if we're in the middle of a split
  86          * screen.  Move to the last line in the current screen -- this makes
  87          * terminal scrolling happen naturally.  Note: *don't* move past the
  88          * end of the screen, as there are ex commands (e.g., :read ! cat file)
  89          * that don't want to.  Don't clear the info line, its contents may be
  90          * valid, e.g. :file|append.
  91          */
  92         if (F_ISSET(sp, SC_SCR_VI)) {
  93                 F_CLR(sp, SC_SCR_VI);
  94
  95                 if (sp->q.cqe_next != (void *)&sp->wp->scrq) {
  96                         (void)wmove(win, RLNO(sp, sp->rows), 0);
  97                         wclrtobot(win);
  98                 }
  99                 (void)wmove(win, RLNO(sp, sp->rows) - 1, 0);
 100                 wrefresh(win);
 101         }
 102
 103         /* Enter the requested mode. */
 104         if (LF_ISSET(SC_EX)) {
 105                 if (cl_ex_init(sp))
 106                         return (1);
 107                 F_SET(clp, CL_IN_EX | CL_SCR_EX_INIT);
 108
 109                 /*
 110                  * If doing an ex screen for ex mode, move to the last line
 111                  * on the screen.
 112                  */
 113                 if (F_ISSET(sp, SC_EX) && clp->cup != NULL)
 114                         tputs(tgoto(clp->cup,
 115                             0, O_VAL(sp, O_LINES) - 1), 1, cl_putchar);
 116         } else {
 117                 if (cl_vi_init(sp))
 118                         return (1);
 119                 F_CLR(clp, CL_IN_EX);
 120                 F_SET(clp, CL_SCR_VI_INIT);
 121         }
 122         return (0);
 123 }
 124
 125 /*
 126  * cl_quit --
 127  *      Shutdown the screens.
 128  *
 129  * PUBLIC: int cl_quit __P((GS *));
 130  */
 131 int
 132 cl_quit(gp)
 133         GS *gp;
 134 {
 135         CL_PRIVATE *clp;
 136         int rval;
 137
 138         rval = 0;
 139         clp = GCLP(gp);
 140
 141         /*
 142          * If we weren't really running, ignore it.  This happens if the
 143          * screen changes size before we've called curses.
 144          */
 145         if (!F_ISSET(clp, CL_SCR_EX_INIT | CL_SCR_VI_INIT))
 146                 return (0);
 147
 148         /* Clean up the terminal mappings. */
 149         if (cl_term_end(gp))
 150                 rval = 1;
 151
 152         /* Really leave vi mode. */
 153         if (F_ISSET(clp, CL_STDIN_TTY) &&
 154             F_ISSET(clp, CL_SCR_VI_INIT) && cl_vi_end(gp))
 155                 rval = 1;
 156
 157         /* Really leave ex mode. */
 158         if (F_ISSET(clp, CL_STDIN_TTY) &&
 159             F_ISSET(clp, CL_SCR_EX_INIT) && cl_ex_end(gp))
 160                 rval = 1;
 161
 162         /*
 163          * If we were running ex when we quit, or we're using an implementation
 164          * of curses where endwin() doesn't get this right, restore the original
 165          * terminal modes.
 166          *
 167          * XXX
 168          * We always do this because it's too hard to figure out what curses
 169          * implementations get it wrong.  It may discard type-ahead characters
 170          * from the tty queue.
 171          */
 172         (void)tcsetattr(STDIN_FILENO, TCSADRAIN | TCSASOFT, &clp->orig);
 173
 174         F_CLR(clp, CL_SCR_EX_INIT | CL_SCR_VI_INIT);
 175         return (rval);
 176 }
 177
 178 /*
 179  * cl_vi_init --
 180  *      Initialize the curses vi screen.
 181  */
 182 static int
 183 cl_vi_init(sp)
 184         SCR *sp;
 185 {
 186         CL_PRIVATE *clp;
 187         GS *gp;
 188         char *o_cols, *o_lines, *o_term, *ttype;
 189
 190         gp = sp->gp;
 191         clp = CLP(sp);
 192
 193         /* If already initialized, just set the terminal modes. */
 194         if (F_ISSET(clp, CL_SCR_VI_INIT))
 195                 goto fast;
 196
 197         /* Curses vi always reads from (and writes to) a terminal. */
 198         if (!F_ISSET(clp, CL_STDIN_TTY) || !isatty(STDOUT_FILENO)) {
 199                 msgq(sp, M_ERR,
 200                     "016|Vi's standard input and output must be a terminal");
 201                 return (1);
 202         }
 203
 204         /* We'll need a terminal type. */
 205         if (opts_empty(sp, O_TERM, 0))
 206                 return (1);
 207         ttype = O_STR(sp, O_TERM);
 208
 209         /*
 210          * XXX
 211          * Changing the row/column and terminal values is done by putting them
 212          * into the environment, which is then read by curses.  What this loses
 213          * in ugliness, it makes up for in stupidity.  We can't simply put the
 214          * values into the environment ourselves, because in the presence of a
 215          * kernel mechanism for returning the window size, entering values into
 216          * the environment will screw up future screen resizing events, e.g. if
 217          * the user enters a :shell command and then resizes their window.  So,
 218          * if they weren't already in the environment, we make sure to delete
 219          * them immediately after setting them.
 220          *
 221          * XXX
 222          * Putting the TERM variable into the environment is necessary, even
 223          * though we're using newterm() here.  We may be using initscr() as
 224          * the underlying function.
 225          */
 226         o_term = getenv("TERM");
 227         cl_putenv("TERM", ttype, 0);
 228         o_lines = getenv("LINES");
 229         cl_putenv("LINES", NULL, (u_long)O_VAL(sp, O_LINES));
 230         o_cols = getenv("COLUMNS");
 231         cl_putenv("COLUMNS", NULL, (u_long)O_VAL(sp, O_COLUMNS));
 232
 233         /*
 234          * We don't care about the SCREEN reference returned by newterm, we
 235          * never have more than one SCREEN at a time.
 236          *
 237          * XXX
 238          * The SunOS initscr() can't be called twice.  Don't even think about
 239          * using it.  It fails in subtle ways (e.g. select(2) on fileno(stdin)
 240          * stops working).  (The SVID notes that applications should only call
 241          * initscr() once.)
 242          *
 243          * XXX
 244          * The HP/UX newterm doesn't support the NULL first argument, so we
 245          * have to specify the terminal type.
 246          */
 247         errno = 0;
 248         if (newterm(ttype, stdout, stdin) == NULL) {
 249                 if (errno)
 250                         msgq(sp, M_SYSERR, "%s", ttype);
 251                 else
 252                         msgq(sp, M_ERR, "%s: unknown terminal type", ttype);
 253                 return (1);
 254         }
 255
 256         if (o_term == NULL)
 257                 unsetenv("TERM");
 258         if (o_lines == NULL)
 259                 unsetenv("LINES");
 260         if (o_cols == NULL)
 261                 unsetenv("COLUMNS");
 262
 263         /*
 264          * XXX
 265          * Someone got let out alone without adult supervision -- the SunOS
 266          * newterm resets the signal handlers.  There's a race, but it's not
 267          * worth closing.
 268          */
 269         (void)sig_init(sp->gp, sp);
 270
 271         /*
 272          * We use raw mode.  What we want is 8-bit clean, however, signals
 273          * and flow control should continue to work.  Admittedly, it sounds
 274          * like cbreak, but it isn't.  Using cbreak() can get you additional
 275          * things like IEXTEN, which turns on flags like DISCARD and LNEXT.
 276          *
 277          * !!!
 278          * If raw isn't turning off echo and newlines, something's wrong.
 279          * However, it shouldn't hurt.
 280          */
 281         noecho();                       /* No character echo. */
 282         nonl();                         /* No CR/NL translation. */
 283         raw();                          /* 8-bit clean. */
 284         idlok(stdscr, 1);               /* Use hardware insert/delete line. */
 285
 286         /* Put the cursor keys into application mode. */
 287         (void)keypad(stdscr, TRUE);
 288
 289         /*
 290          * XXX
 291          * The screen TI sequence just got sent.  See the comment in
 292          * cl_funcs.c:cl_attr().
 293          */
 294         clp->ti_te = TI_SENT;
 295
 296         /*
 297          * XXX
 298          * Historic implementations of curses handled SIGTSTP signals
 299          * in one of three ways.  They either:
 300          *
 301          *      1: Set their own handler, regardless.
 302          *      2: Did not set a handler if a handler was already installed.
 303          *      3: Set their own handler, but then called any previously set
 304          *         handler after completing their own cleanup.
 305          *
 306          * We don't try and figure out which behavior is in place, we force
 307          * it to SIG_DFL after initializing the curses interface, which means
 308          * that curses isn't going to take the signal.  Since curses isn't
 309          * reentrant (i.e., the whole curses SIGTSTP interface is a fantasy),
 310          * we're doing The Right Thing.
 311          */
 312         (void)signal(SIGTSTP, SIG_DFL);
 313
 314         /*
 315          * If flow control was on, turn it back on.  Turn signals on.  ISIG
 316          * turns on VINTR, VQUIT, VDSUSP and VSUSP.   The main curses code
 317          * already installed a handler for VINTR.  We're going to disable the
 318          * other three.
 319          *
 320          * XXX
 321          * We want to use ^Y as a vi scrolling command.  If the user has the
 322          * DSUSP character set to ^Y (common practice) clean it up.  As it's
 323          * equally possible that the user has VDSUSP set to 'a', we disable
 324          * it regardless.  It doesn't make much sense to suspend vi at read,
 325          * so I don't think anyone will care.  Alternatively, we could look
 326          * it up in the table of legal command characters and turn it off if
 327          * it matches one.  VDSUSP wasn't in POSIX 1003.1-1990, so we test for
 328          * it.
 329          *
 330          * XXX
 331          * We don't check to see if the user had signals enabled originally.
 332          * If they didn't, it's unclear what we're supposed to do here, but
 333          * it's also pretty unlikely.
 334          */
 335         if (tcgetattr(STDIN_FILENO, &clp->vi_enter)) {
 336                 msgq(sp, M_SYSERR, "tcgetattr");
 337                 goto err;
 338         }
 339         if (clp->orig.c_iflag & IXON)
 340                 clp->vi_enter.c_iflag |= IXON;
 341         if (clp->orig.c_iflag & IXOFF)
 342                 clp->vi_enter.c_iflag |= IXOFF;
 343
 344         clp->vi_enter.c_lflag |= ISIG;
 345 #ifdef VDSUSP
 346         clp->vi_enter.c_cc[VDSUSP] = _POSIX_VDISABLE;
 347 #endif
 348         clp->vi_enter.c_cc[VQUIT] = _POSIX_VDISABLE;
 349         clp->vi_enter.c_cc[VSUSP] = _POSIX_VDISABLE;
 350
 351         /*
 352          * XXX
 353          * OSF/1 doesn't turn off the <discard>, <literal-next> or <status>
 354          * characters when curses switches into raw mode.  It should be OK
 355          * to do it explicitly for everyone.
 356          */
 357 #ifdef VDISCARD
 358         clp->vi_enter.c_cc[VDISCARD] = _POSIX_VDISABLE;
 359 #endif
 360 #ifdef VLNEXT
 361         clp->vi_enter.c_cc[VLNEXT] = _POSIX_VDISABLE;
 362 #endif
 363 #ifdef VSTATUS
 364         clp->vi_enter.c_cc[VSTATUS] = _POSIX_VDISABLE;
 365 #endif
 366
 367         /* Initialize terminal based information. */
 368         if (cl_term_init(sp))
 369                 goto err;
 370
 371 fast:   /* Set the terminal modes. */
 372         if (tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &clp->vi_enter)) {
 373                 msgq(sp, M_SYSERR, "tcsetattr");
 374 err:            (void)cl_vi_end(sp->gp);
 375                 return (1);
 376         }
 377         return (0);
 378 }
 379
 380 /*
 381  * cl_vi_end --
 382  *      Shutdown the vi screen.
 383  */
 384 static int
 385 cl_vi_end(gp)
 386         GS *gp;
 387 {
 388         CL_PRIVATE *clp;
 389
 390         clp = GCLP(gp);
 391
 392         /* Restore the cursor keys to normal mode. */
 393         (void)keypad(stdscr, FALSE);
 394
 395         /*
 396          * If we were running vi when we quit, scroll the screen up a single
 397          * line so we don't lose any information.
 398          *
 399          * Move to the bottom of the window (some endwin implementations don't
 400          * do this for you).
 401          */
 402         if (!F_ISSET(clp, CL_IN_EX)) {
 403                 (void)move(0, 0);
 404                 (void)deleteln();
 405                 (void)move(LINES - 1, 0);
 406                 (void)refresh();
 407         }
 408
 409         cl_freecap(clp);
 410
 411         /* End curses window. */
 412         (void)endwin();
 413
 414         /*
 415          * XXX
 416          * The screen TE sequence just got sent.  See the comment in
 417          * cl_funcs.c:cl_attr().
 418          */
 419         clp->ti_te = TE_SENT;
 420
 421         return (0);
 422 }
 423
 424 /*
 425  * cl_ex_init --
 426  *      Initialize the ex screen.
 427  */
 428 static int
 429 cl_ex_init(sp)
 430         SCR *sp;
 431 {
 432         CL_PRIVATE *clp;
 433
 434         clp = CLP(sp);
 435
 436         /* If already initialized, just set the terminal modes. */
 437         if (F_ISSET(clp, CL_SCR_EX_INIT))
 438                 goto fast;
 439
 440         /* If not reading from a file, we're done. */
 441         if (!F_ISSET(clp, CL_STDIN_TTY))
 442                 return (0);
 443
 444         /* Get the ex termcap/terminfo strings. */
 445         (void)cl_getcap(sp, "cup", &clp->cup);
 446         (void)cl_getcap(sp, "smso", &clp->smso);
 447         (void)cl_getcap(sp, "rmso", &clp->rmso);
 448         (void)cl_getcap(sp, "el", &clp->el);
 449         (void)cl_getcap(sp, "cuu1", &clp->cuu1);
 450
 451         /* Enter_standout_mode and exit_standout_mode are paired. */
 452         if (clp->smso == NULL || clp->rmso == NULL) {
 453                 if (clp->smso != NULL) {
 454                         free(clp->smso);
 455                         clp->smso = NULL;
 456                 }
 457                 if (clp->rmso != NULL) {
 458                         free(clp->rmso);
 459                         clp->rmso = NULL;
 460                 }
 461         }
 462
 463         /*
 464          * Turn on canonical mode, with normal input and output processing.
 465          * Start with the original terminal settings as the user probably
 466          * had them (including any local extensions) set correctly for the
 467          * current terminal.
 468          *
 469          * !!!
 470          * We can't get everything that we need portably; for example, ONLCR,
 471          * mapping <newline> to <carriage-return> on output isn't required
 472          * by POSIX 1003.1b-1993.  If this turns out to be a problem, then
 473          * we'll either have to play some games on the mapping, or we'll have
 474          * to make all ex printf's output \r\n instead of \n.
 475          */
 476         clp->ex_enter = clp->orig;
 477         clp->ex_enter.c_lflag  |= ECHO | ECHOE | ECHOK | ICANON | IEXTEN | ISIG;
 478 #ifdef ECHOCTL
 479         clp->ex_enter.c_lflag |= ECHOCTL;
 480 #endif
 481 #ifdef ECHOKE
 482         clp->ex_enter.c_lflag |= ECHOKE;
 483 #endif
 484         clp->ex_enter.c_iflag |= ICRNL;
 485         clp->ex_enter.c_oflag |= OPOST;
 486 #ifdef ONLCR
 487         clp->ex_enter.c_oflag |= ONLCR;
 488 #endif
 489
 490 fast:   if (tcsetattr(STDIN_FILENO, TCSADRAIN | TCSASOFT, &clp->ex_enter)) {
 491                 msgq(sp, M_SYSERR, "tcsetattr");
 492                 return (1);
 493         }
 494         return (0);
 495 }
 496
 497 /*
 498  * cl_ex_end --
 499  *      Shutdown the ex screen.
 500  */
 501 static int
 502 cl_ex_end(gp)
 503         GS *gp;
 504 {
 505         CL_PRIVATE *clp;
 506
 507         clp = GCLP(gp);
 508
 509         cl_freecap(clp);
 510
 511         return (0);
 512 }
 513
 514 /*
 515  * cl_getcap --
 516  *      Retrieve termcap/terminfo strings.
 517  *
 518  * PUBLIC: int cl_getcap __P((SCR *, char *, char **));
 519  */
 520 int
 521 cl_getcap(sp, name, elementp)
 522         SCR *sp;
 523         char *name, **elementp;
 524 {
 525         size_t len;
 526         char *t;
 527
 528         if ((t = tigetstr(name)) != NULL &&
 529             t != (char *)-1 && (len = strlen(t)) != 0) {
 530                 MALLOC_RET(sp, *elementp, char *, len + 1);
 531                 memmove(*elementp, t, len + 1);
 532         }
 533         return (0);
 534 }
 535
 536 /*
 537  * cl_freecap --
 538  *      Free any allocated termcap/terminfo strings.
 539  */
 540 static void
 541 cl_freecap(clp)
 542         CL_PRIVATE *clp;
 543 {
 544         if (clp->el != NULL) {
 545                 free(clp->el);
 546                 clp->el = NULL;
 547         }
 548         if (clp->cup != NULL) {
 549                 free(clp->cup);
 550                 clp->cup = NULL;
 551         }
 552         if (clp->cuu1 != NULL) {
 553                 free(clp->cuu1);
 554                 clp->cuu1 = NULL;
 555         }
 556         if (clp->rmso != NULL) {
 557                 free(clp->rmso);
 558                 clp->rmso = NULL;
 559         }
 560         if (clp->smso != NULL) {
 561                 free(clp->smso);
 562                 clp->smso = NULL;
 563         }
 564 }
 565
 566 /*
 567  * cl_putenv --
 568  *      Put a value into the environment.
 569  */
 570 static int
 571 cl_putenv(name, str, value)
 572         char *name, *str;
 573         u_long value;
 574
 575 {
 576         char buf[40];
 577
 578         if (str == NULL) {
 579                 (void)snprintf(buf, sizeof(buf), "%lu", value);
 580                 return (setenv(name, buf, 1));
 581         } else
 582                 return (setenv(name, str, 1));
 583 }