subr_terminal.c

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    1 /*-
    2  * Copyright (c) 2009 The FreeBSD Foundation
    3  * All rights reserved.
    4  *
    5  * This software was developed by Ed Schouten under sponsorship from the
    6  * FreeBSD Foundation.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   27  * SUCH DAMAGE.
   28  */
   29 
   30 #include <sys/cdefs.h>
   31 __FBSDID("$FreeBSD$");
   32 
   33 #include <sys/param.h>
   34 #include <sys/cons.h>
   35 #include <sys/consio.h>
   36 #include <sys/kernel.h>
   37 #include <sys/lock.h>
   38 #include <sys/malloc.h>
   39 #include <sys/mutex.h>
   40 #include <sys/systm.h>
   41 #include <sys/terminal.h>
   42 #include <sys/tty.h>
   43 
   44 #include <machine/stdarg.h>
   45 
   46 static MALLOC_DEFINE(M_TERMINAL, "terminal", "terminal device");
   47 
   48 /*
   49  * Locking.
   50  *
   51  * Normally we don't need to lock down the terminal emulator, because
   52  * the TTY lock is already held when calling teken_input().
   53  * Unfortunately this is not the case when the terminal acts as a
   54  * console device, because cnputc() can be called at the same time.
   55  * This means terminals may need to be locked down using a spin lock.
   56  */
   57 #define TERMINAL_LOCK(tm)       do {                                    \
   58         if ((tm)->tm_flags & TF_CONS)                                   \
   59                 mtx_lock_spin(&(tm)->tm_mtx);                           \
   60         else if ((tm)->tm_tty != NULL)                                  \
   61                 tty_lock((tm)->tm_tty);                                 \
   62 } while (0)
   63 #define TERMINAL_UNLOCK(tm)     do {                                    \
   64         if ((tm)->tm_flags & TF_CONS)                                   \
   65                 mtx_unlock_spin(&(tm)->tm_mtx);                         \
   66         else if ((tm)->tm_tty != NULL)                                  \
   67                 tty_unlock((tm)->tm_tty);                               \
   68 } while (0)
   69 #define TERMINAL_LOCK_TTY(tm)   do {                                    \
   70         if ((tm)->tm_flags & TF_CONS)                                   \
   71                 mtx_lock_spin(&(tm)->tm_mtx);                           \
   72 } while (0)
   73 #define TERMINAL_UNLOCK_TTY(tm) do {                                    \
   74         if ((tm)->tm_flags & TF_CONS)                                   \
   75                 mtx_unlock_spin(&(tm)->tm_mtx);                         \
   76 } while (0)
   77 #define TERMINAL_LOCK_CONS(tm)          mtx_lock_spin(&(tm)->tm_mtx)
   78 #define TERMINAL_UNLOCK_CONS(tm)        mtx_unlock_spin(&(tm)->tm_mtx)
   79 
   80 /*
   81  * TTY routines.
   82  */
   83 
   84 static tsw_open_t       termtty_open;
   85 static tsw_close_t      termtty_close;
   86 static tsw_outwakeup_t  termtty_outwakeup;
   87 static tsw_ioctl_t      termtty_ioctl;
   88 static tsw_mmap_t       termtty_mmap;
   89 
   90 static struct ttydevsw terminal_tty_class = {
   91         .tsw_open       = termtty_open,
   92         .tsw_close      = termtty_close,
   93         .tsw_outwakeup  = termtty_outwakeup,
   94         .tsw_ioctl      = termtty_ioctl,
   95         .tsw_mmap       = termtty_mmap,
   96 };
   97 
   98 /*
   99  * Terminal emulator routines.
  100  */
  101 
  102 static tf_bell_t        termteken_bell;
  103 static tf_cursor_t      termteken_cursor;
  104 static tf_putchar_t     termteken_putchar;
  105 static tf_fill_t        termteken_fill;
  106 static tf_copy_t        termteken_copy;
  107 static tf_param_t       termteken_param;
  108 static tf_respond_t     termteken_respond;
  109 
  110 static teken_funcs_t terminal_drawmethods = {
  111         .tf_bell        = termteken_bell,
  112         .tf_cursor      = termteken_cursor,
  113         .tf_putchar     = termteken_putchar,
  114         .tf_fill        = termteken_fill,
  115         .tf_copy        = termteken_copy,
  116         .tf_param       = termteken_param,
  117         .tf_respond     = termteken_respond,
  118 };
  119 
  120 /* Kernel message formatting. */
  121 static const teken_attr_t kernel_message = {
  122         .ta_fgcolor     = TCHAR_FGCOLOR(TERMINAL_KERN_ATTR),
  123         .ta_bgcolor     = TCHAR_BGCOLOR(TERMINAL_KERN_ATTR),
  124         .ta_format      = TCHAR_FORMAT(TERMINAL_KERN_ATTR)
  125 };
  126 
  127 static const teken_attr_t default_message = {
  128         .ta_fgcolor     = TCHAR_FGCOLOR(TERMINAL_NORM_ATTR),
  129         .ta_bgcolor     = TCHAR_BGCOLOR(TERMINAL_NORM_ATTR),
  130         .ta_format      = TCHAR_FORMAT(TERMINAL_NORM_ATTR)
  131 };
  132 
  133 /* Fudge fg brightness as TF_BOLD (shifted). */
  134 #define TCOLOR_FG_FUDGED(color) __extension__ ({                        \
  135         teken_color_t _c;                                               \
  136                                                                         \
  137         _c = (color);                                                   \
  138         TCOLOR_FG(_c & 7) | ((_c & 8) << 18);                           \
  139 })
  140 
  141 /* Fudge bg brightness as TF_BLINK (shifted). */
  142 #define TCOLOR_BG_FUDGED(color) __extension__ ({                        \
  143         teken_color_t _c;                                               \
  144                                                                         \
  145         _c = (color);                                                   \
  146         TCOLOR_BG(_c & 7) | ((_c & 8) << 20);                           \
  147 })
  148 
  149 #define TCOLOR_256TO16(color) __extension__ ({                          \
  150         teken_color_t _c;                                               \
  151                                                                         \
  152         _c = (color);                                                   \
  153         if (_c >= 16)                                                   \
  154                 _c = teken_256to16(_c);                                 \
  155         _c;                                                             \
  156 })
  157 
  158 #define TCHAR_CREATE(c, a)      ((c) | TFORMAT((a)->ta_format) |        \
  159         TCOLOR_FG_FUDGED(TCOLOR_256TO16((a)->ta_fgcolor)) |             \
  160         TCOLOR_BG_FUDGED(TCOLOR_256TO16((a)->ta_bgcolor)))
  161 
  162 static void
  163 terminal_init(struct terminal *tm)
  164 {
  165 
  166         if (tm->tm_flags & TF_CONS)
  167                 mtx_init(&tm->tm_mtx, "trmlck", NULL, MTX_SPIN);
  168         teken_init(&tm->tm_emulator, &terminal_drawmethods, tm);
  169         teken_set_defattr(&tm->tm_emulator, &default_message);
  170 }
  171 
  172 struct terminal *
  173 terminal_alloc(const struct terminal_class *tc, void *softc)
  174 {
  175         struct terminal *tm;
  176 
  177         tm = malloc(sizeof(struct terminal), M_TERMINAL, M_WAITOK|M_ZERO);
  178         terminal_init(tm);
  179 
  180         tm->tm_class = tc;
  181         tm->tm_softc = softc;
  182 
  183         return (tm);
  184 }
  185 
  186 static void
  187 terminal_sync_ttysize(struct terminal *tm)
  188 {
  189         struct tty *tp;
  190 
  191         tp = tm->tm_tty;
  192         if (tp == NULL)
  193                 return;
  194 
  195         tty_lock(tp);
  196         tty_set_winsize(tp, &tm->tm_winsize);
  197         tty_unlock(tp);
  198 }
  199 
  200 void
  201 terminal_maketty(struct terminal *tm, const char *fmt, ...)
  202 {
  203         struct tty *tp;
  204         char name[8];
  205         va_list ap;
  206 
  207         va_start(ap, fmt);
  208         vsnrprintf(name, sizeof name, 32, fmt, ap);
  209         va_end(ap);
  210 
  211         tp = tty_alloc(&terminal_tty_class, tm);
  212         tty_makedev(tp, NULL, "%s", name);
  213         tm->tm_tty = tp;
  214         terminal_sync_ttysize(tm);
  215 }
  216 
  217 void
  218 terminal_set_cursor(struct terminal *tm, const term_pos_t *pos)
  219 {
  220 
  221         teken_set_cursor(&tm->tm_emulator, pos);
  222 }
  223 
  224 void
  225 terminal_set_winsize_blank(struct terminal *tm, const struct winsize *size,
  226     int blank, const term_attr_t *attr)
  227 {
  228         term_rect_t r;
  229 
  230         tm->tm_winsize = *size;
  231 
  232         r.tr_begin.tp_row = r.tr_begin.tp_col = 0;
  233         r.tr_end.tp_row = size->ws_row;
  234         r.tr_end.tp_col = size->ws_col;
  235 
  236         TERMINAL_LOCK(tm);
  237         if (blank == 0)
  238                 teken_set_winsize_noreset(&tm->tm_emulator, &r.tr_end);
  239         else
  240                 teken_set_winsize(&tm->tm_emulator, &r.tr_end);
  241         TERMINAL_UNLOCK(tm);
  242 
  243         if ((blank != 0) && !(tm->tm_flags & TF_MUTE))
  244                 tm->tm_class->tc_fill(tm, &r,
  245                     TCHAR_CREATE((teken_char_t)' ', attr));
  246 
  247         terminal_sync_ttysize(tm);
  248 }
  249 
  250 void
  251 terminal_set_winsize(struct terminal *tm, const struct winsize *size)
  252 {
  253 
  254         terminal_set_winsize_blank(tm, size, 1,
  255             (const term_attr_t *)&default_message);
  256 }
  257 
  258 /*
  259  * XXX: This function is a kludge.  Drivers like vt(4) need to
  260  * temporarily stop input when resizing, etc.  This should ideally be
  261  * handled within the driver.
  262  */
  263 
  264 void
  265 terminal_mute(struct terminal *tm, int yes)
  266 {
  267 
  268         TERMINAL_LOCK(tm);
  269         if (yes)
  270                 tm->tm_flags |= TF_MUTE;
  271         else
  272                 tm->tm_flags &= ~TF_MUTE;
  273         TERMINAL_UNLOCK(tm);
  274 }
  275 
  276 void
  277 terminal_input_char(struct terminal *tm, term_char_t c)
  278 {
  279         struct tty *tp;
  280 
  281         tp = tm->tm_tty;
  282         if (tp == NULL)
  283                 return;
  284 
  285         /*
  286          * Strip off any attributes. Also ignore input of second part of
  287          * CJK fullwidth characters, as we don't want to return these
  288          * characters twice.
  289          */
  290         if (TCHAR_FORMAT(c) & TF_CJK_RIGHT)
  291                 return;
  292         c = TCHAR_CHARACTER(c);
  293 
  294         tty_lock(tp);
  295         /*
  296          * Conversion to UTF-8.
  297          */
  298         if (c < 0x80) {
  299                 ttydisc_rint(tp, c, 0);
  300         } else if (c < 0x800) {
  301                 char str[2] = {
  302                         0xc0 | (c >> 6),
  303                         0x80 | (c & 0x3f)
  304                 };
  305 
  306                 ttydisc_rint_simple(tp, str, sizeof str);
  307         } else if (c < 0x10000) {
  308                 char str[3] = {
  309                         0xe0 | (c >> 12),
  310                         0x80 | ((c >> 6) & 0x3f),
  311                         0x80 | (c & 0x3f)
  312                 };
  313 
  314                 ttydisc_rint_simple(tp, str, sizeof str);
  315         } else {
  316                 char str[4] = {
  317                         0xf0 | (c >> 18),
  318                         0x80 | ((c >> 12) & 0x3f),
  319                         0x80 | ((c >> 6) & 0x3f),
  320                         0x80 | (c & 0x3f)
  321                 };
  322 
  323                 ttydisc_rint_simple(tp, str, sizeof str);
  324         }
  325         ttydisc_rint_done(tp);
  326         tty_unlock(tp);
  327 }
  328 
  329 void
  330 terminal_input_raw(struct terminal *tm, char c)
  331 {
  332         struct tty *tp;
  333 
  334         tp = tm->tm_tty;
  335         if (tp == NULL)
  336                 return;
  337 
  338         tty_lock(tp);
  339         ttydisc_rint(tp, c, 0);
  340         ttydisc_rint_done(tp);
  341         tty_unlock(tp);
  342 }
  343 
  344 void
  345 terminal_input_special(struct terminal *tm, unsigned int k)
  346 {
  347         struct tty *tp;
  348         const char *str;
  349 
  350         tp = tm->tm_tty;
  351         if (tp == NULL)
  352                 return;
  353 
  354         str = teken_get_sequence(&tm->tm_emulator, k);
  355         if (str == NULL)
  356                 return;
  357 
  358         tty_lock(tp);
  359         ttydisc_rint_simple(tp, str, strlen(str));
  360         ttydisc_rint_done(tp);
  361         tty_unlock(tp);
  362 }
  363 
  364 /*
  365  * Binding with the TTY layer.
  366  */
  367 
  368 static int
  369 termtty_open(struct tty *tp)
  370 {
  371         struct terminal *tm = tty_softc(tp);
  372 
  373         tm->tm_class->tc_opened(tm, 1);
  374         return (0);
  375 }
  376 
  377 static void
  378 termtty_close(struct tty *tp)
  379 {
  380         struct terminal *tm = tty_softc(tp);
  381 
  382         tm->tm_class->tc_opened(tm, 0);
  383 }
  384 
  385 static void
  386 termtty_outwakeup(struct tty *tp)
  387 {
  388         struct terminal *tm = tty_softc(tp);
  389         char obuf[128];
  390         size_t olen;
  391         unsigned int flags = 0;
  392 
  393         while ((olen = ttydisc_getc(tp, obuf, sizeof obuf)) > 0) {
  394                 TERMINAL_LOCK_TTY(tm);
  395                 if (!(tm->tm_flags & TF_MUTE)) {
  396                         tm->tm_flags &= ~TF_BELL;
  397                         teken_input(&tm->tm_emulator, obuf, olen);
  398                         flags |= tm->tm_flags;
  399                 }
  400                 TERMINAL_UNLOCK_TTY(tm);
  401         }
  402 
  403         TERMINAL_LOCK_TTY(tm);
  404         if (!(tm->tm_flags & TF_MUTE))
  405                 tm->tm_class->tc_done(tm);
  406         TERMINAL_UNLOCK_TTY(tm);
  407         if (flags & TF_BELL)
  408                 tm->tm_class->tc_bell(tm);
  409 }
  410 
  411 static int
  412 termtty_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
  413 {
  414         struct terminal *tm = tty_softc(tp);
  415         int error;
  416 
  417         switch (cmd) {
  418         case CONS_GETINFO: {
  419                 vid_info_t *vi = (vid_info_t *)data;
  420                 const teken_pos_t *p;
  421                 int fg, bg;
  422 
  423                 if (vi->size != sizeof(vid_info_t))
  424                         return (EINVAL);
  425 
  426                 /* Already help the console driver by filling in some data. */
  427                 p = teken_get_cursor(&tm->tm_emulator);
  428                 vi->mv_row = p->tp_row;
  429                 vi->mv_col = p->tp_col;
  430 
  431                 p = teken_get_winsize(&tm->tm_emulator);
  432                 vi->mv_rsz = p->tp_row;
  433                 vi->mv_csz = p->tp_col;
  434 
  435                 teken_get_defattr_cons25(&tm->tm_emulator, &fg, &bg);
  436                 vi->mv_norm.fore = fg;
  437                 vi->mv_norm.back = bg;
  438                 /* XXX: keep vidcontrol happy; bold backgrounds. */
  439                 vi->mv_rev.fore = bg;
  440                 vi->mv_rev.back = fg & 0x7;
  441                 break;
  442         }
  443         }
  444 
  445         /*
  446          * Unlike various other drivers, this driver will never
  447          * deallocate TTYs.  This means it's safe to temporarily unlock
  448          * the TTY when handling ioctls.
  449          */
  450         tty_unlock(tp);
  451         error = tm->tm_class->tc_ioctl(tm, cmd, data, td);
  452         tty_lock(tp);
  453         return (error);
  454 }
  455 
  456 static int
  457 termtty_mmap(struct tty *tp, vm_ooffset_t offset, vm_paddr_t * paddr,
  458     int nprot, vm_memattr_t *memattr)
  459 {
  460         struct terminal *tm = tty_softc(tp);
  461 
  462         return (tm->tm_class->tc_mmap(tm, offset, paddr, nprot, memattr));
  463 }
  464 
  465 /*
  466  * Binding with the kernel and debug console.
  467  */
  468 
  469 static cn_probe_t       termcn_cnprobe;
  470 static cn_init_t        termcn_cninit;
  471 static cn_term_t        termcn_cnterm;
  472 static cn_getc_t        termcn_cngetc;
  473 static cn_putc_t        termcn_cnputc;
  474 static cn_grab_t        termcn_cngrab;
  475 static cn_ungrab_t      termcn_cnungrab;
  476 
  477 const struct consdev_ops termcn_cnops = {
  478         .cn_probe       = termcn_cnprobe,
  479         .cn_init        = termcn_cninit,
  480         .cn_term        = termcn_cnterm,
  481         .cn_getc        = termcn_cngetc,
  482         .cn_putc        = termcn_cnputc,
  483         .cn_grab        = termcn_cngrab,
  484         .cn_ungrab      = termcn_cnungrab,
  485 };
  486 
  487 void
  488 termcn_cnregister(struct terminal *tm)
  489 {
  490         struct consdev *cp;
  491 
  492         cp = tm->consdev;
  493         if (cp == NULL) {
  494                 cp = malloc(sizeof(struct consdev), M_TERMINAL,
  495                     M_WAITOK|M_ZERO);
  496                 cp->cn_ops = &termcn_cnops;
  497                 cp->cn_arg = tm;
  498                 cp->cn_pri = CN_INTERNAL;
  499                 sprintf(cp->cn_name, "ttyv0");
  500 
  501                 tm->tm_flags = TF_CONS;
  502                 tm->consdev = cp;
  503 
  504                 terminal_init(tm);
  505         }
  506 
  507         /* Attach terminal as console. */
  508         cnadd(cp);
  509 }
  510 
  511 static void
  512 termcn_cngrab(struct consdev *cp)
  513 {
  514         struct terminal *tm = cp->cn_arg;
  515 
  516         tm->tm_class->tc_cngrab(tm);
  517 }
  518 
  519 static void
  520 termcn_cnungrab(struct consdev *cp)
  521 {
  522         struct terminal *tm = cp->cn_arg;
  523 
  524         tm->tm_class->tc_cnungrab(tm);
  525 }
  526 
  527 static void
  528 termcn_cnprobe(struct consdev *cp)
  529 {
  530         struct terminal *tm = cp->cn_arg;
  531 
  532         if (tm == NULL) {
  533                 cp->cn_pri = CN_DEAD;
  534                 return;
  535         }
  536 
  537         tm->consdev = cp;
  538         terminal_init(tm);
  539 
  540         tm->tm_class->tc_cnprobe(tm, cp);
  541 }
  542 
  543 static void
  544 termcn_cninit(struct consdev *cp)
  545 {
  546 
  547 }
  548 
  549 static void
  550 termcn_cnterm(struct consdev *cp)
  551 {
  552 
  553 }
  554 
  555 static int
  556 termcn_cngetc(struct consdev *cp)
  557 {
  558         struct terminal *tm = cp->cn_arg;
  559 
  560         return (tm->tm_class->tc_cngetc(tm));
  561 }
  562 
  563 static void
  564 termcn_cnputc(struct consdev *cp, int c)
  565 {
  566         struct terminal *tm = cp->cn_arg;
  567         teken_attr_t backup;
  568         char cv = c;
  569 
  570         TERMINAL_LOCK_CONS(tm);
  571         if (!(tm->tm_flags & TF_MUTE)) {
  572                 backup = *teken_get_curattr(&tm->tm_emulator);
  573                 teken_set_curattr(&tm->tm_emulator, &kernel_message);
  574                 teken_input(&tm->tm_emulator, &cv, 1);
  575                 teken_set_curattr(&tm->tm_emulator, &backup);
  576                 tm->tm_class->tc_done(tm);
  577         }
  578         TERMINAL_UNLOCK_CONS(tm);
  579 }
  580 
  581 /*
  582  * Binding with the terminal emulator.
  583  */
  584 
  585 static void
  586 termteken_bell(void *softc)
  587 {
  588         struct terminal *tm = softc;
  589 
  590         tm->tm_flags |= TF_BELL;
  591 }
  592 
  593 static void
  594 termteken_cursor(void *softc, const teken_pos_t *p)
  595 {
  596         struct terminal *tm = softc;
  597 
  598         tm->tm_class->tc_cursor(tm, p);
  599 }
  600 
  601 static void
  602 termteken_putchar(void *softc, const teken_pos_t *p, teken_char_t c,
  603     const teken_attr_t *a)
  604 {
  605         struct terminal *tm = softc;
  606 
  607         tm->tm_class->tc_putchar(tm, p, TCHAR_CREATE(c, a));
  608 }
  609 
  610 static void
  611 termteken_fill(void *softc, const teken_rect_t *r, teken_char_t c,
  612     const teken_attr_t *a)
  613 {
  614         struct terminal *tm = softc;
  615 
  616         tm->tm_class->tc_fill(tm, r, TCHAR_CREATE(c, a));
  617 }
  618 
  619 static void
  620 termteken_copy(void *softc, const teken_rect_t *r, const teken_pos_t *p)
  621 {
  622         struct terminal *tm = softc;
  623 
  624         tm->tm_class->tc_copy(tm, r, p);
  625 }
  626 
  627 static void
  628 termteken_param(void *softc, int cmd, unsigned int arg)
  629 {
  630         struct terminal *tm = softc;
  631 
  632         tm->tm_class->tc_param(tm, cmd, arg);
  633 }
  634 
  635 static void
  636 termteken_respond(void *softc, const void *buf, size_t len)
  637 {
  638 #if 0
  639         struct terminal *tm = softc;
  640         struct tty *tp;
  641 
  642         /*
  643          * Only inject a response into the TTY if the data actually
  644          * originated from the TTY.
  645          *
  646          * XXX: This cannot be done right now.  The TTY could pick up
  647          * other locks.  It could also in theory cause loops, when the
  648          * TTY performs echoing of a command that generates even more
  649          * input.
  650          */
  651         tp = tm->tm_tty;
  652         if (tp == NULL)
  653                 return;
  654 
  655         ttydisc_rint_simple(tp, buf, len);
  656         ttydisc_rint_done(tp);
  657 #endif
  658 }
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FreeBSD/Linux Kernel Cross Reference sys/kern/subr_terminal.c

FreeBSD/Linux Kernel Cross Reference
sys/kern/subr_terminal.c
