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BOOK.TXT：源码内容

11022 * |------------+----------+---------+---------|
11023 * | SET_ALARM | proc_nr |f to call| delta |
11024 * |------------+----------+---------+---------|
11025 * | SET_SYN_AL | proc_nr | | delta |
11026 * ---------------------------------------------
11027 * NEW_TIME, DELTA_CLICKS, and SECONDS_LEFT all refer to the same field in
11028 * the message, depending upon the message type.
11029 *
11030 * Reply messages are of type OK, except in the case of a HARD_INT, to
11031 * which no reply is generated. For the GET_* messages the time is returned
11032 * in the NEW_TIME field, and for the SET_ALARM and SET_SYN_AL the time
11033 * in seconds remaining until the alarm is returned is returned in the same
11034 * field.
11035 *
11036 * When an alarm goes off, if the caller is a user process, a SIGALRM signal
11037 * is sent to it. If it is a task, a function specified by the caller will
11038 * be invoked. This function may, for example, send a message, but only if
11039 * it is certain that the task will be blocked when the timer goes off. A
11040 * synchronous alarm sends a message to the synchronous alarm task, which
11041 * in turn can dispatch a message to another server. This is the only way
11042 * to send an alarm to a server, since servers cannot use the function-call
11043 * mechanism available to tasks and servers cannot receive signals.
11044 */
11045
11046 #include "kernel.h"
11047 #include <signal.h>
11048 #include <minix/callnr.h>
11049 #include <minix/com.h>
11050 #include "proc.h"
11051
11052 /* Constant definitions. */
11053 #define MILLISEC 100 /* how often to call the scheduler (msec) */
11054 #define SCHED_RATE (MILLISEC*HZ/1000) /* number of ticks per schedule */
11055
11056 /* Clock parameters. */
11057 #define COUNTER_FREQ (2*TIMER_FREQ) /* counter frequency using sqare wave*/
11058 #define LATCH_COUNT 0x00 /* cc00xxxx, c = channel, x = any */
11059 #define SQUARE_WAVE 0x36 /* ccaammmb, a = access, m = mode, b = BCD */
11060 /* 11x11, 11 = LSB then MSB, x11 = sq wave */
11061 #define TIMER_COUNT ((unsigned) (TIMER_FREQ/HZ)) /* initial value for counter*/
11062 #define TIMER_FREQ 1193182L /* clock frequency for timer in PC and AT */
11063
11064 #define CLOCK_ACK_BIT 0x80 /* PS/2 clock interrupt acknowledge bit */
11065
11066 /* Clock task variables. */
11067 PRIVATE clock_t realtime; /* real time clock */
11068 PRIVATE time_t boot_time; /* time in seconds of system boot */
11069 PRIVATE clock_t next_alarm; /* probable time of next alarm */
11070 PRIVATE message mc; /* message buffer for both input and output */
11071 PRIVATE int watchdog_proc; /* contains proc_nr at call of *watch_dog[]*/
11072 PRIVATE watchdog_t watch_dog[NR_TASKS+NR_PROCS];
11073
11074 /* Variables used by both clock task and synchronous alarm task */
11075 PRIVATE int syn_al_alive= TRUE; /* don't wake syn_alrm_task before inited*/
11076 PRIVATE int syn_table[NR_TASKS+NR_PROCS]; /* which tasks get CLOCK_INT*/
11077
11078 /* Variables changed by interrupt handler */
11079 PRIVATE clock_t pending_ticks; /* ticks seen by low level only */
11080 PRIVATE int sched_ticks = SCHED_RATE; /* counter: when 0, call scheduler */
11081 PRIVATE struct proc *prev_ptr; /* last user process run by clock task */
11082
11083 FORWARD _PROTOTYPE( void common_setalarm, (int proc_nr,
11084 long delta_ticks, watchdog_t fuction) );
11085 FORWARD _PROTOTYPE( void do_clocktick, (void) );
11086 FORWARD _PROTOTYPE( void do_get_time, (void) );
11087 FORWARD _PROTOTYPE( void do_getuptime, (void) );
11088 FORWARD _PROTOTYPE( void do_set_time, (message *m_ptr) );
11089 FORWARD _PROTOTYPE( void do_setalarm, (message *m_ptr) );
11090 FORWARD _PROTOTYPE( void init_clock, (void) );
11091 FORWARD _PROTOTYPE( void cause_alarm, (void) );
11092 FORWARD _PROTOTYPE( void do_setsyn_alrm, (message *m_ptr) );
11093 FORWARD _PROTOTYPE( int clock_handler, (int irq) );
11094
11095 /*===========================================================================*
11096 * clock_task *
11097 *===========================================================================*/
11098 PUBLIC void clock_task()
11099 {
11100 /* Main program of clock task. It corrects realtime by adding pending
11101 * ticks seen only by the interrupt service, then it determines which
11102 * of the 6 possible calls this is by looking at 'mc.m_type'. Then
11103 * it dispatches.
11104 */
11105
11106 int opcode;
11107
11108 init_clock(); /* initialize clock task */
11109
11110 /* Main loop of the clock task. Get work, process it, sometimes reply. */
11111 while (TRUE) {
11112 receive(ANY, &mc); /* go get a message */
11113 opcode = mc.m_type; /* extract the function code */
11114
11115 lock();
11116 realtime += pending_ticks; /* transfer ticks from low level handler */
11117 pending_ticks = 0; /* so we don't have to worry about them */
11118 unlock();
11119
11120 switch (opcode) {
11121 case HARD_INT: do_clocktick(); break;
11122 case GET_UPTIME: do_getuptime(); break;
11123 case GET_TIME: do_get_time(); break;
11124 case SET_TIME: do_set_time(&mc); break;
11125 case SET_ALARM: do_setalarm(&mc); break;
11126 case SET_SYNC_AL:do_setsyn_alrm(&mc); break;
11127 default: panic("clock task got bad message", mc.m_type);
11128 }
11129
11130 /* Send reply, except for clock tick. */
11131 mc.m_type = OK;
11132 if (opcode != HARD_INT) send(mc.m_source, &mc);
11133 }
11134 }
11137 /*===========================================================================*
11138 * do_clocktick *
11139 *===========================================================================*/
11140 PRIVATE void do_clocktick()
11141 {
11142 /* Despite its name, this routine is not called on every clock tick. It
11143 * is called on those clock ticks when a lot of work needs to be done.
11144 */
11145
11146 register struct proc *rp;
11147 register int proc_nr;
11148
11149 if (next_alarm <= realtime) {
11150 /* An alarm may have gone off, but proc may have exited, so check. */
11151 next_alarm = LONG_MAX; /* start computing next alarm */
11152 for (rp = BEG_PROC_ADDR; rp < END_PROC_ADDR; rp++) {
11153 if (rp->p_alarm != 0) {
11154 /* See if this alarm time has been reached. */
11155 if (rp->p_alarm <= realtime) {
11156 /* A timer has gone off. If it is a user proc,
11157 * send it a signal. If it is a task, call the
11158 * function previously specified by the task.
11159 */
11160 proc_nr = proc_number(rp);
11161 if (watch_dog[proc_nr+NR_TASKS]) {
11162 watchdog_proc= proc_nr;
11163 (*watch_dog[proc_nr+NR_TASKS])();
11164 }
11165 else
11166 cause_sig(proc_nr, SIGALRM);
11167 rp->p_alarm = 0;
11168 }
11169
11170 /* Work on determining which alarm is next. */
11171 if (rp->p_alarm != 0 && rp->p_alarm < next_alarm)
11172 next_alarm = rp->p_alarm;
11173 }
11174 }
11175 }
11176
11177 /* If a user process has been running too long, pick another one. */
11178 if (--sched_ticks == 0) {
11179 if (bill_ptr == prev_ptr) lock_sched(); /* process has run too long */
11180 sched_ticks = SCHED_RATE; /* reset quantum */
11181 prev_ptr = bill_ptr; /* new previous process */
11182 }
11183 }
11186 /*===========================================================================*
11187 * do_getuptime *
11188 *===========================================================================*/
11189 PRIVATE void do_getuptime()
11190 {
11191 /* Get and return the current clock uptime in ticks. */
11192
11193 mc.NEW_TIME = realtime; /* current uptime */
11194 }
11197 /*===========================================================================*
11198 * get_uptime *
11199 *===========================================================================*/
11200 PUBLIC clock_t get_uptime()
11201 {
11202 /* Get and return the current clock uptime in ticks. This function is
11203 * designed to be called from other tasks, so they can get uptime without
11204 * the overhead of messages. It has to be careful about pending_ticks.
11205 */
11206
11207 clock_t uptime;
11208
11209 lock();
11210 uptime = realtime + pending_ticks;
11211 unlock();
11212 return(uptime);
11213 }
11216 /*===========================================================================*
11217 * do_get_time *
11218 *===========================================================================*/
11219 PRIVATE void do_get_time()
11220 {
11221 /* Get and return the current clock time in seconds. */
11222
11223 mc.NEW_TIME = boot_time + realtime/HZ; /* current real time */
11224 }
11227 /*===========================================================================*
11228 * do_set_time *
11229 *===========================================================================*/
11230 PRIVATE void do_set_time(m_ptr)
11231 message *m_ptr; /* pointer to request message */
11232 {
11233 /* Set the real time clock. Only the superuser can use this call. */
11234
11235 boot_time = m_ptr->NEW_TIME - realtime/HZ;
11236 }
11239 /*===========================================================================*
11240 * do_setalarm *
11241 *===========================================================================*/
11242 PRIVATE void do_setalarm(m_ptr)
11243 message *m_ptr; /* pointer to request message */
11244 {
11245 /* A process wants an alarm signal or a task wants a given watch_dog function
11246 * called after a specified interval.
11247 */
11248
11249 register struct proc *rp;
11250 int proc_nr; /* which process wants the alarm */
11251 long delta_ticks; /* in how many clock ticks does he want it? */
11252 watchdog_t function; /* function to call (tasks only) */
11253
11254 /* Extract the parameters from the message. */
11255 proc_nr = m_ptr->CLOCK_PROC_NR; /* process to interrupt later */
11256 delta_ticks = m_ptr->DELTA_TICKS; /* how many ticks to wait */
11257 function = (watchdog_t) m_ptr->FUNC_TO_CALL;
11258 /* function to call (tasks only) */
11259 rp = proc_addr(proc_nr);
11260 mc.SECONDS_LEFT = (rp->p_alarm == 0 ? 0 : (rp->p_alarm - realtime)/HZ );
11261 if (!istaskp(rp)) function= 0; /* user processes get signaled */
11262 common_setalarm(proc_nr, delta_ticks, function);
11263 }
11266 /*===========================================================================*
11267 * do_setsyn_alrm *
11268 *===========================================================================*/
11269 PRIVATE void do_setsyn_alrm(m_ptr)
11270 message *m_ptr; /* pointer to request message */
11271 {
11272 /* A process wants a synchronous alarm.
11273 */
11274
11275 register struct proc *rp;
11276 int proc_nr; /* which process wants the alarm */
11277 long delta_ticks; /* in how many clock ticks does he want it? */
11278
11279 /* Extract the parameters from the message. */
11280 proc_nr = m_ptr->CLOCK_PROC_NR; /* process to interrupt later */
11281 delta_ticks = m_ptr->DELTA_TICKS; /* how many ticks to wait */
11282 rp = proc_addr(proc_nr);
11283 mc.SECONDS_LEFT = (rp->p_alarm == 0 ? 0 : (rp->p_alarm - realtime)/HZ );
11284 common_setalarm(proc_nr, delta_ticks, cause_alarm);
11285 }
11288 /*===========================================================================*
11289 * common_setalarm *
11290 *===========================================================================*/
11291 PRIVATE void common_setalarm(proc_nr, delta_ticks, function)
11292 int proc_nr; /* which process wants the alarm */
11293 long delta_ticks; /* in how many clock ticks does he want it? */
11294 watchdog_t function; /* function to call (0 if cause_sig is
11295 * to be called */
11296 {
11297 /* Finish up work of do_set_alarm and do_setsyn_alrm. Record an alarm
11298 * request and check to see if it is the next alarm needed.
11299 */
11300
11301 register struct proc *rp;
11302
11303 rp = proc_addr(proc_nr);
11304 rp->p_alarm = (delta_ticks == 0 ? 0 : realtime + delta_ticks);
11305 watch_dog[proc_nr+NR_TASKS] = function;
11306
11307 /* Which alarm is next? */
11308 next_alarm = LONG_MAX;
11309 for (rp = BEG_PROC_ADDR; rp < END_PROC_ADDR; rp++)
11310 if(rp->p_alarm != 0 && rp->p_alarm < next_alarm)next_alarm=rp->p_alarm;
11311
11312 }
11315 /*===========================================================================*
11316 * cause_alarm *
11317 *===========================================================================*/
11318 PRIVATE void cause_alarm()
11319 {
11320 /* Routine called if a timer goes off and the process requested a synchronous
11321 * alarm. The process number is in the global variable watchdog_proc (HACK).
11322 */
11323 message mess;
11324
11325 syn_table[watchdog_proc + NR_TASKS]= TRUE;
11326 if (!syn_al_alive) send (SYN_ALRM_TASK, &mess);
11327 }
11330 /*===========================================================================*
11331 * syn_alrm_task *
11332 *===========================================================================*/
11333 PUBLIC void syn_alrm_task()
11334 {
11335 /* Main program of the synchronous alarm task.
11336 * This task receives messages only from cause_alarm in the clock task.
11337 * It sends a CLOCK_INT message to a process that requested a syn_alrm.
11338 * Synchronous alarms are so called because, unlike a signals or the
11339 * activation of a watchdog, a synchronous alarm is received by a process
11340 * when it is in a known part of its code, that is, when it has issued
11341 * a call to receive a message.
11342 */
11343
11344 message mess;
11345 int work_done; /* ready to sleep ? */
11346 int *al_ptr; /* pointer in syn_table */
11347 int i;
11348
11349 syn_al_alive= TRUE;
11350 for (i= 0, al_ptr= syn_table; i<NR_TASKS+NR_PROCS; i++, al_ptr++)
11351 *al_ptr= FALSE;
11352
11353 while (TRUE) {
11354 work_done= TRUE;
11355 for (i= 0, al_ptr= syn_table; i<NR_TASKS+NR_PROCS; i++, al_ptr++)
11356 if (*al_ptr) {
11357 *al_ptr= FALSE;
11358 mess.m_type= CLOCK_INT;
11359 send (i-NR_TASKS, &mess);
11360 work_done= FALSE;
11361 }
11362 if (work_done) {
11363 syn_al_alive= FALSE;
11364 receive (CLOCK, &mess);
11365 syn_al_alive= TRUE;
11366 }
11367 }
11368 }
11371 /*===========================================================================*
11372 * clock_handler *
11373 *===========================================================================*/
11374 PRIVATE int clock_handler(irq)
11375 int irq;
11376 {
11377 /* This executes on every clock tick (i.e., every time the timer chip
11378 * generates an interrupt). It does a little bit of work so the clock
11379 * task does not have to be called on every tick.
11380 *
11381 * Switch context to do_clocktick if an alarm has gone off.
11382 * Also switch there to reschedule if the reschedule will do something.
11383 * This happens when
11384 * (1) quantum has expired
11385 * (2) current process received full quantum (as clock sampled it!)
11386 * (3) something else is ready to run.
11387 * Also call TTY and PRINTER and let them do whatever is necessary.
11388 *
11389 * Many global global and static variables are accessed here. The safety
11390 * of this must be justified. Most of them are not changed here:
11391 * k_reenter:
11392 * This safely tells if the clock interrupt is nested.
11393 * proc_ptr, bill_ptr:
11394 * These are used for accounting. It does not matter if proc.c
11395 * is changing them, provided they are always valid pointers,
11396 * since at worst the previous process would be billed.
11397 * next_alarm, realtime, sched_ticks, bill_ptr, prev_ptr,
11398 * rdy_head[USER_Q]:
11399 * These are tested to decide whether to call interrupt(). It
11400 * does not matter if the test is sometimes (rarely) backwards
11401 * due to a race, since this will only delay the high-level
11402 * processing by one tick, or call the high level unnecessarily.
11403 * The variables which are changed require more care:
11404 * rp->user_time, rp->sys_time:
11405 * These are protected by explicit locks in system.c. They are
11406 * not properly protected in dmp.c (the increment here is not
11407 * atomic) but that hardly matters.
11408 * pending_ticks:
11409 * This is protected by explicit locks in clock.c. Don't
11410 * update realtime directly, since there are too many
11411 * references to it to guard conveniently.
11412 * lost_ticks:
11413 * Clock ticks counted outside the clock task.
11414 * sched_ticks, prev_ptr:
11415 * Updating these competes with similar code in do_clocktick().
11416 * No lock is necessary, because if bad things happen here
11417 * (like sched_ticks going negative), the code in do_clocktick()
11418 * will restore the variables to reasonable values, and an
11419 * occasional missed or extra sched() is harmless.
11420 *
11421 * Are these complications worth the trouble? Well, they make the system 15%
11422 * faster on a 5MHz 8088, and make task debugging much easier since there are
11423 * no task switches on an inactive system.
11424 */
11425
11426 register struct proc *rp;
11427 register unsigned ticks;
11428 clock_t now;
11429
11430 if (ps_mca) {
11431 /* Acknowledge the PS/2 clock interrupt. */
11432 out_byte(PORT_B, in_byte(PORT_B) | CLOCK_ACK_BIT);
11433 }
11434
11435 /* Update user and system accounting times.
11436 * First charge the current process for user time.
11437 * If the current process is not the billable process (usually because it
11438 * is a task), charge the billable process for system time as well.
11439 * Thus the unbillable tasks' user time is the billable users' system time.
11440 */
11441 if (k_reenter != 0)
11442 rp = proc_addr(HARDWARE);
11443 else
11444 rp = proc_ptr;
11445 ticks = lost_ticks + 1;
11446 lost_ticks = 0;
11447 rp->user_time += ticks;
11448 if (rp != bill_ptr && rp != proc_addr(IDLE)) bill_ptr->sys_time += ticks;
11449
11450 pending_ticks += ticks;
11451 now = realtime + pending_ticks;
11452 if (tty_timeout <= now) tty_wakeup(now); /* possibly wake up TTY */
11453 pr_restart(); /* possibly restart printer */
11454
11455 if (next_alarm <= now ||
11456 sched_ticks == 1 &&
11457 bill_ptr == prev_ptr &&
11458 rdy_head[USER_Q] != NIL_PROC) {
11459 interrupt(CLOCK);
11460 return 1; /* Reenable interrupts */
11461 }
11462
11463 if (--sched_ticks == 0) {
11464 /* If bill_ptr == prev_ptr, no ready users so don't need sched(). */
11465 sched_ticks = SCHED_RATE; /* reset quantum */
11466 prev_ptr = bill_ptr; /* new previous process */
11467 }
11468 return 1; /* Reenable clock interrupt */
11469 }
11471 /*===========================================================================*
11472 * init_clock *
11473 *===========================================================================*/
11474 PRIVATE void init_clock()
11475 {
11476 /* Initialize channel 0 of the 8253A timer to e.g. 60 Hz. */
11477
11478 out_byte(TIMER_MODE, SQUARE_WAVE); /* set timer to run continuously */
11479 out_byte(TIMER0, TIMER_COUNT); /* load timer low byte */
11480 out_byte(TIMER0, TIMER_COUNT >> 8); /* load timer high byte */
11481 put_irq_handler(CLOCK_IRQ, clock_handler); /* set the interrupt handler */
11482 enable_irq(CLOCK_IRQ); /* ready for clock interrupts */
11483 }
11486 /*===========================================================================*
11487 * clock_stop *
11488 *===========================================================================*/
11489 PUBLIC void clock_stop()
11490 {
11491 /* Reset the clock to the BIOS rate. (For rebooting) */
11492
11493 out_byte(TIMER_MODE, 0x36);
11494 out_byte(TIMER0, 0);
11495 out_byte(TIMER0, 0);
11496 }
11499 /*==========================================================================*
11500 * milli_delay *
11501 *==========================================================================*/
11502 PUBLIC void milli_delay(millisec)
11503 unsigned millisec;
11504 {
11505 /* Delay some milliseconds. */
11506
11507 struct milli_state ms;
11508
11509 milli_start(&ms);
11510 while (milli_elapsed(&ms) < millisec) {}
11511 }
11513 /*==========================================================================*
11514 * milli_start *
11515 *==========================================================================*/
11516 PUBLIC void milli_start(msp)
11517 struct milli_state *msp;
11518 {
11519 /* Prepare for calls to milli_elapsed(). */
11520
11521 msp->prev_count = 0;
11522 msp->accum_count = 0;
11523 }
11526 /*==========================================================================*
11527 * milli_elapsed *
11528 *==========================================================================*/
11529 PUBLIC unsigned milli_elapsed(msp)
11530 struct milli_state *msp;
11531 {
11532 /* Return the number of milliseconds since the call to milli_start(). Must be
11533 * polled rapidly.
11534 */
11535 unsigned count;
11536
11537 /* Read the counter for channel 0 of the 8253A timer. The counter
11538 * decrements at twice the timer frequency (one full cycle for each
11539 * half of square wave). The counter normally has a value between 0
11540 * and TIMER_COUNT, but before the clock task has been initialized,
11541 * its maximum value is 65535, as set by the BIOS.
11542 */
11543 out_byte(TIMER_MODE, LATCH_COUNT); /* make chip copy count to latch */
11544 count = in_byte(TIMER0); /* countdown continues during 2-step read */
11545 count |= in_byte(TIMER0) << 8;
11546
11547 /* Add difference between previous and new count unless the counter has
11548 * increased (restarted its cycle). We may lose a tick now and then, but
11549 * microsecond precision is not needed.
11550 */
11551 msp->accum_count += count <= msp->prev_count ? (msp->prev_count - count) : 1;
11552 msp->prev_count = count;
11553
11554 return msp->accum_count / (TIMER_FREQ / 1000);
11555 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/tty.h
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
11600 /* tty.h - Terminals */
11601
11602 #define TTY_IN_BYTES 256 /* tty input queue size */
11603 #define TAB_SIZE 8 /* distance between tab stops */
11604 #define TAB_MASK 7 /* mask to compute a tab stop position */
11605
11606 #define ESC '33' /* escape */
11607
11608 #define O_NOCTTY 00400 /* from <fcntl.h>, or cc will choke */
11609 #define O_NONBLOCK 04000
11610
11611 typedef _PROTOTYPE( void (*devfun_t), (struct tty *tp) );
11612 typedef _PROTOTYPE( void (*devfunarg_t), (struct tty *tp, int c) );
11613
11614 typedef struct tty {
11615 int tty_events; /* set when TTY should inspect this line */
11616
11617 /* Input queue. Typed characters are stored here until read by a program. */
11618 u16_t *tty_inhead; /* pointer to place where next char goes */
11619 u16_t *tty_intail; /* pointer to next char to be given to prog */
11620 int tty_incount; /* # chars in the input queue */
11621 int tty_eotct; /* number of "line breaks" in input queue */
11622 devfun_t tty_devread; /* routine to read from low level buffers */
11623 devfun_t tty_icancel; /* cancel any device input */
11624 int tty_min; /* minimum requested #chars in input queue */
11625 clock_t tty_time; /* time when the input is available */
11626 struct tty *tty_timenext; /* for a list of ttys with active timers */
11627
11628 /* Output section. */
11629 devfun_t tty_devwrite; /* routine to start actual device output */
11630 devfunarg_t tty_echo; /* routine to echo characters input */
11631 devfun_t tty_ocancel; /* cancel any ongoing device output */
11632 devfun_t tty_break; /* let the device send a break */
11633
11634 /* Terminal parameters and status. */
11635 int tty_position; /* current position on the screen for echoing */
11636 char tty_reprint; /* 1 when echoed input messed up, else 0 */
11637 char tty_escaped; /* 1 when LNEXT (^V) just seen, else 0 */
11638 char tty_inhibited; /* 1 when STOP (^S) just seen (stops output) */
11639 char tty_pgrp; /* slot number of controlling process */
11640 char tty_openct; /* count of number of opens of this tty */
11641
11642 /* Information about incomplete I/O requests is stored here. */
11643 char tty_inrepcode; /* reply code, TASK_REPLY or REVIVE */
11644 char tty_incaller; /* process that made the call (usually FS) */
11645 char tty_inproc; /* process that wants to read from tty */
11646 vir_bytes tty_in_vir; /* virtual address where data is to go */
11647 int tty_inleft; /* how many chars are still needed */
11648 int tty_incum; /* # chars input so far */
11649 char tty_outrepcode; /* reply code, TASK_REPLY or REVIVE */
11650 char tty_outcaller; /* process that made the call (usually FS) */
11651 char tty_outproc; /* process that wants to write to tty */
11652 vir_bytes tty_out_vir; /* virtual address where data comes from */
11653 int tty_outleft; /* # chars yet to be output */
11654 int tty_outcum; /* # chars output so far */
11655 char tty_iocaller; /* process that made the call (usually FS) */
11656 char tty_ioproc; /* process that wants to do an ioctl */
11657 int tty_ioreq; /* ioctl request code */
11658 vir_bytes tty_iovir; /* virtual address of ioctl buffer */
11659
11660 /* Miscellaneous. */
11661 devfun_t tty_ioctl; /* set line speed, etc. at the device level */
11662 devfun_t tty_close; /* tell the device that the tty is closed */
11663 void *tty_priv; /* pointer to per device private data */
11664 struct termios tty_termios; /* terminal attributes */
11665 struct winsize tty_winsize; /* window size (#lines and #columns) */
11666
11667 u16_t tty_inbuf[TTY_IN_BYTES];/* tty input buffer */
11668 } tty_t;
11669
11670 EXTERN tty_t tty_table[NR_CONS+NR_RS_LINES+NR_PTYS];
11671
11672 /* Values for the fields. */
11673 #define NOT_ESCAPED 0 /* previous character is not LNEXT (^V) */
11674 #define ESCAPED 1 /* previous character was LNEXT (^V) */
11675 #define RUNNING 0 /* no STOP (^S) has been typed to stop output */
11676 #define STOPPED 1 /* STOP (^S) has been typed to stop output */
11677
11678 /* Fields and flags on characters in the input queue. */
11679 #define IN_CHAR 0x00FF /* low 8 bits are the character itself */
11680 #define IN_LEN 0x0F00 /* length of char if it has been echoed */
11681 #define IN_LSHIFT 8 /* length = (c & IN_LEN) >> IN_LSHIFT */
11682 #define IN_EOT 0x1000 /* char is a line break (^D, LF) */
11683 #define IN_EOF 0x2000 /* char is EOF (^D), do not return to user */
11684 #define IN_ESC 0x4000 /* escaped by LNEXT (^V), no interpretation */
11685
11686 /* Times and timeouts. */
11687 #define TIME_NEVER ((clock_t) -1 < 0 ? (clock_t) LONG_MAX : (clock_t) -1)
11688 #define force_timeout() ((void) (tty_timeout = 0))
11689
11690 EXTERN tty_t *tty_timelist; /* list of ttys with active timers */
11691
11692 /* Number of elements and limit of a buffer. */
11693 #define buflen(buf) (sizeof(buf) / sizeof((buf)[0]))
11694 #define bufend(buf) ((buf) + buflen(buf))
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/tty.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
11700 /* This file contains the terminal driver, both for the IBM console and regular
11701 * ASCII terminals. It handles only the device-independent part of a TTY, the
11702 * device dependent parts are in console.c, rs232.c, etc. This file contains
11703 * two main entry points, tty_task() and tty_wakeup(), and several minor entry
11704 * points for use by the device-dependent code.
11705 *
11706 * The device-independent part accepts "keyboard" input from the device-
11707 * dependent part, performs input processing (special key interpretation),
11708 * and sends the input to a process reading from the TTY. Output to a TTY
11709 * is sent to the device-dependent code for output processing and "screen"
11710 * display. Input processing is done by the device by calling 'in_process'
11711 * on the input characters, output processing may be done by the device itself
11712 * or by calling 'out_process'. The TTY takes care of input queuing, the
11713 * device does the output queuing. If a device receives an external signal,
11714 * like an interrupt, then it causes tty_wakeup() to be run by the CLOCK task
11715 * to, you guessed it, wake up the TTY to check if input or output can
11716 * continue.
11717 *
11718 * The valid messages and their parameters are:
11719 *
11720 * HARD_INT: output has been completed or input has arrived
11721 * DEV_READ: a process wants to read from a terminal
11722 * DEV_WRITE: a process wants to write on a terminal
11723 * DEV_IOCTL: a process wants to change a terminal's parameters
11724 * DEV_OPEN: a tty line has been opened
11725 * DEV_CLOSE: a tty line has been closed
11726 * CANCEL: terminate a previous incomplete system call immediately
11727 *
11728 * m_type TTY_LINE PROC_NR COUNT TTY_SPEK TTY_FLAGS ADDRESS
11729 * ---------------------------------------------------------------------------
11730 * | HARD_INT | | | | | | |
11731 * |-------------+---------+---------+---------+---------+---------+---------|
11732 * | DEV_READ |minor dev| proc nr | count | O_NONBLOCK| buf ptr |
11733 * |-------------+---------+---------+---------+---------+---------+---------|
11734 * | DEV_WRITE |minor dev| proc nr | count | | | buf ptr |
11735 * |-------------+---------+---------+---------+---------+---------+---------|
11736 * | DEV_IOCTL |minor dev| proc nr |func code|erase etc| flags | |
11737 * |-------------+---------+---------+---------+---------+---------+---------|
11738 * | DEV_OPEN |minor dev| proc nr | O_NOCTTY| | | |
11739 * |-------------+---------+---------+---------+---------+---------+---------|
11740 * | DEV_CLOSE |minor dev| proc nr | | | | |
11741 * |-------------+---------+---------+---------+---------+---------+---------|
11742 * | CANCEL |minor dev| proc nr | | | | |
11743 * ---------------------------------------------------------------------------
11744 */
11745
11746 #include "kernel.h"
11747 #include <termios.h>
11748 #include <sys/ioctl.h>
11749 #include <signal.h>
11750 #include <minix/callnr.h>
11751 #include <minix/com.h>
11752 #include <minix/keymap.h>
11753 #include "tty.h"
11754 #include "proc.h"
11755
11756 /* Address of a tty structure. */
11757 #define tty_addr(line) (&tty_table[line])
11758
11759 /* First minor numbers for the various classes of TTY devices. */
11760 #define CONS_MINOR 0
11761 #define LOG_MINOR 15
11762 #define RS232_MINOR 16
11763 #define TTYPX_MINOR 128
11764 #define PTYPX_MINOR 192
11765
11766 /* Macros for magic tty types. */
11767 #define isconsole(tp) ((tp) < tty_addr(NR_CONS))
11768
11769 /* Macros for magic tty structure pointers. */
11770 #define FIRST_TTY tty_addr(0)
11771 #define END_TTY tty_addr(sizeof(tty_table) / sizeof(tty_table[0]))
11772
11773 /* A device exists if at least its 'devread' function is defined. */
11774 #define tty_active(tp) ((tp)->tty_devread != NULL)
11775
11776 /* RS232 lines or pseudo terminals can be completely configured out. */
11777 #if NR_RS_LINES == 0
11778 #define rs_init(tp) ((void) 0)
11779 #endif
11780 #if NR_PTYS == 0
11781 #define pty_init(tp) ((void) 0)
11782 #define do_pty(tp, mp) ((void) 0)
11783 #endif
11784
11785 FORWARD _PROTOTYPE( void do_cancel, (tty_t *tp, message *m_ptr) );
11786 FORWARD _PROTOTYPE( void do_ioctl, (tty_t *tp, message *m_ptr) );
11787 FORWARD _PROTOTYPE( void do_open, (tty_t *tp, message *m_ptr) );
11788 FORWARD _PROTOTYPE( void do_close, (tty_t *tp, message *m_ptr) );
11789 FORWARD _PROTOTYPE( void do_read, (tty_t *tp, message *m_ptr) );
11790 FORWARD _PROTOTYPE( void do_write, (tty_t *tp, message *m_ptr) );
11791 FORWARD _PROTOTYPE( void in_transfer, (tty_t *tp) );
11792 FORWARD _PROTOTYPE( int echo, (tty_t *tp, int ch) );
11793 FORWARD _PROTOTYPE( void rawecho, (tty_t *tp, int ch) );
11794 FORWARD _PROTOTYPE( int back_over, (tty_t *tp) );
11795 FORWARD _PROTOTYPE( void reprint, (tty_t *tp) );
11796 FORWARD _PROTOTYPE( void dev_ioctl, (tty_t *tp) );
11797 FORWARD _PROTOTYPE( void setattr, (tty_t *tp) );
11798 FORWARD _PROTOTYPE( void tty_icancel, (tty_t *tp) );
11799 FORWARD _PROTOTYPE( void tty_init, (tty_t *tp) );
11800 FORWARD _PROTOTYPE( void settimer, (tty_t *tp, int on) );
11801
11802 /* Default attributes. */
11803 PRIVATE struct termios termios_defaults = {
11804 TINPUT_DEF, TOUTPUT_DEF, TCTRL_DEF, TLOCAL_DEF, TSPEED_DEF, TSPEED_DEF,
11805 {
11806 TEOF_DEF, TEOL_DEF, TERASE_DEF, TINTR_DEF, TKILL_DEF, TMIN_DEF,
11807 TQUIT_DEF, TTIME_DEF, TSUSP_DEF, TSTART_DEF, TSTOP_DEF,
11808 TREPRINT_DEF, TLNEXT_DEF, TDISCARD_DEF,
11809 },
11810 };
11811 PRIVATE struct winsize winsize_defaults; /* = all zeroes */
11812
11813
11814 /*===========================================================================*
11815 * tty_task *
11816 *===========================================================================*/
11817 PUBLIC void tty_task()
11818 {
11819 /* Main routine of the terminal task. */
11820
11821 message tty_mess; /* buffer for all incoming messages */
11822 register tty_t *tp;
11823 unsigned line;
11824
11825 /* Initialize the terminal lines. */
11826 for (tp = FIRST_TTY; tp < END_TTY; tp++) tty_init(tp);
11827
11828 /* Display the Minix startup banner. */
11829 printf("Minix %s.%s Copyright 1997 Prentice-Hall, Inc.nn",
11830 OS_RELEASE, OS_VERSION);
11831 printf("Executing in 32-bit protected modenn");
11832
11833 while (TRUE) {
11834 /* Handle any events on any of the ttys. */
11835 for (tp = FIRST_TTY; tp < END_TTY; tp++) {
11836 if (tp->tty_events) handle_events(tp);
11837 }
11838
11839 receive(ANY, &tty_mess);
11840
11841 /* A hardware interrupt is an invitation to check for events. */
11842 if (tty_mess.m_type == HARD_INT) continue;
11843
11844 /* Check the minor device number. */
11845 line = tty_mess.TTY_LINE;
11846 if ((line - CONS_MINOR) < NR_CONS) {
11847 tp = tty_addr(line - CONS_MINOR);
11848 } else
11849 if (line == LOG_MINOR) {
11850 tp = tty_addr(0);
11851 } else
11852 if ((line - RS232_MINOR) < NR_RS_LINES) {
11853 tp = tty_addr(line - RS232_MINOR + NR_CONS);
11854 } else
11855 if ((line - TTYPX_MINOR) < NR_PTYS) {
11856 tp = tty_addr(line - TTYPX_MINOR + NR_CONS + NR_RS_LINES);
11857 } else
11858 if ((line - PTYPX_MINOR) < NR_PTYS) {
11859 tp = tty_addr(line - PTYPX_MINOR + NR_CONS + NR_RS_LINES);
11860 do_pty(tp, &tty_mess);
11861 continue; /* this is a pty, not a tty */
11862 } else {
11863 tp = NULL;
11864 }
11865
11866 /* If the device doesn't exist or is not configured return ENXIO. */
11867 if (tp == NULL || !tty_active(tp)) {
11868 tty_reply(TASK_REPLY, tty_mess.m_source,
11869 tty_mess.PROC_NR, ENXIO);
11870 continue;
11871 }
11872
11873 /* Execute the requested function. */
11874 switch (tty_mess.m_type) {
11875 case DEV_READ: do_read(tp, &tty_mess); break;
11876 case DEV_WRITE: do_write(tp, &tty_mess); break;
11877 case DEV_IOCTL: do_ioctl(tp, &tty_mess); break;
11878 case DEV_OPEN: do_open(tp, &tty_mess); break;
11879 case DEV_CLOSE: do_close(tp, &tty_mess); break;
11880 case CANCEL: do_cancel(tp, &tty_mess); break;
11881 default: tty_reply(TASK_REPLY, tty_mess.m_source,
11882 tty_mess.PROC_NR, EINVAL);
11883 }
11884 }
11885 }
11888 /*===========================================================================*
11889 * do_read *
11890 *===========================================================================*/
11891 PRIVATE void do_read(tp, m_ptr)
11892 register tty_t *tp; /* pointer to tty struct */
11893 message *m_ptr; /* pointer to message sent to the task */
11894 {
11895 /* A process wants to read from a terminal. */
11896 int r;
11897
11898 /* Check if there is already a process hanging in a read, check if the
11899 * parameters are correct, do I/O.
11900 */
11901 if (tp->tty_inleft > 0) {
11902 r = EIO;
11903 } else
11904 if (m_ptr->COUNT <= 0) {
11905 r = EINVAL;
11906 } else
11907 if (numap(m_ptr->PROC_NR, (vir_bytes) m_ptr->ADDRESS, m_ptr->COUNT) == 0) {
11908 r = EFAULT;
11909 } else {
11910 /* Copy information from the message to the tty struct. */
11911 tp->tty_inrepcode = TASK_REPLY;
11912 tp->tty_incaller = m_ptr->m_source;
11913 tp->tty_inproc = m_ptr->PROC_NR;
11914 tp->tty_in_vir = (vir_bytes) m_ptr->ADDRESS;
11915 tp->tty_inleft = m_ptr->COUNT;
11916
11917 if (!(tp->tty_termios.c_lflag & ICANON)
11918 && tp->tty_termios.c_cc[VTIME] > 0) {
11919 if (tp->tty_termios.c_cc[VMIN] == 0) {
11920 /* MIN & TIME specify a read timer that finishes the
11921 * read in TIME/10 seconds if no bytes are available.
11922 */
11923 lock();
11924 settimer(tp, TRUE);
11925 tp->tty_min = 1;
11926 unlock();
11927 } else {
11928 /* MIN & TIME specify an inter-byte timer that may
11929 * have to be cancelled if there are no bytes yet.
11930 */
11931 if (tp->tty_eotct == 0) {
11932 lock();
11933 settimer(tp, FALSE);
11934 unlock();
11935 tp->tty_min = tp->tty_termios.c_cc[VMIN];
11936 }
11937 }
11938 }
11939
11940 /* Anything waiting in the input buffer? Clear it out... */
11941 in_transfer(tp);
11942 /* ...then go back for more */
11943 handle_events(tp);
11944 if (tp->tty_inleft == 0) return; /* already done */
11945
11946 /* There were no bytes in the input queue available, so either suspend
11947 * the caller or break off the read if nonblocking.
11948 */
11949 if (m_ptr->TTY_FLAGS & O_NONBLOCK) {
11950 r = EAGAIN; /* cancel the read */
11951 tp->tty_inleft = tp->tty_incum = 0;
11952 } else {
11953 r = SUSPEND; /* suspend the caller */
11954 tp->tty_inrepcode = REVIVE;
11955 }
11956 }
11957 tty_reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, r);
11958 }
11961 /*===========================================================================*
11962 * do_write *
11963 *===========================================================================*/
11964 PRIVATE void do_write(tp, m_ptr)
11965 register tty_t *tp;
11966 register message *m_ptr; /* pointer to message sent to the task */
11967 {
11968 /* A process wants to write on a terminal. */
11969 int r;
11970
11971 /* Check if there is already a process hanging in a write, check if the
11972 * parameters are correct, do I/O.
11973 */
11974 if (tp->tty_outleft > 0) {
11975 r = EIO;
11976 } else
11977 if (m_ptr->COUNT <= 0) {
11978 r = EINVAL;
11979 } else
11980 if (numap(m_ptr->PROC_NR, (vir_bytes) m_ptr->ADDRESS, m_ptr->COUNT) == 0) {
11981 r = EFAULT;
11982 } else {
11983 /* Copy message parameters to the tty structure. */
11984 tp->tty_outrepcode = TASK_REPLY;
11985 tp->tty_outcaller = m_ptr->m_source;
11986 tp->tty_outproc = m_ptr->PROC_NR;
11987 tp->tty_out_vir = (vir_bytes) m_ptr->ADDRESS;
11988 tp->tty_outleft = m_ptr->COUNT;
11989
11990 /* Try to write. */
11991 handle_events(tp);
11992 if (tp->tty_outleft == 0) return; /* already done */
11993
11994 /* None or not all the bytes could be written, so either suspend the
11995 * caller or break off the write if nonblocking.
11996 */
11997 if (m_ptr->TTY_FLAGS & O_NONBLOCK) { /* cancel the write */
11998 r = tp->tty_outcum > 0 ? tp->tty_outcum : EAGAIN;
11999 tp->tty_outleft = tp->tty_outcum = 0;
12000 } else {
12001 r = SUSPEND; /* suspend the caller */
12002 tp->tty_outrepcode = REVIVE;
12003 }
12004 }
12005 tty_reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, r);
12006 }
12009 /*===========================================================================*
12010 * do_ioctl *
12011 *===========================================================================*/
12012 PRIVATE void do_ioctl(tp, m_ptr)
12013 register tty_t *tp;
12014 message *m_ptr; /* pointer to message sent to task */
12015 {
12016 /* Perform an IOCTL on this terminal. Posix termios calls are handled
12017 * by the IOCTL system call
12018 */
12019
12020 int r;
12021 union {
12022 int i;
12023 /* these non-Posix params are not used now, but the union is retained
12024 * to minimize code differences with backward compatible version
12025 * struct sgttyb sg;
12026 * struct tchars tc;
12027 */
12028 } param;
12029 phys_bytes user_phys;
12030 size_t size;
12031
12032 /* Size of the ioctl parameter. */
12033 switch (m_ptr->TTY_REQUEST) {
12034 case TCGETS: /* Posix tcgetattr function */
12035 case TCSETS: /* Posix tcsetattr function, TCSANOW option */
12036 case TCSETSW: /* Posix tcsetattr function, TCSADRAIN option */
12037 case TCSETSF: /* Posix tcsetattr function, TCSAFLUSH option */
12038 size = sizeof(struct termios);
12039 break;
12040
12041 case TCSBRK: /* Posix tcsendbreak function */
12042 case TCFLOW: /* Posix tcflow function */
12043 case TCFLSH: /* Posix tcflush function */
12044 case TIOCGPGRP: /* Posix tcgetpgrp function */
12045 case TIOCSPGRP: /* Posix tcsetpgrp function */
12046 size = sizeof(int);
12047 break;
12048
12049 case TIOCGWINSZ: /* get window size (not Posix) */
12050 case TIOCSWINSZ: /* set window size (not Posix) */
12051 size = sizeof(struct winsize);
12052 break;
12053
12054 case KIOCSMAP: /* load keymap (Minix extension) */
12055 size = sizeof(keymap_t);
12056 break;
12057
12058 case TIOCSFON: /* load font (Minix extension) */
12059 size = sizeof(u8_t [8192]);
12060 break;
12061
12062 case TCDRAIN: /* Posix tcdrain function -- no parameter */
12063 default: size = 0;
12064 }
12065
12066 if (size != 0) {
12067 user_phys = numap(m_ptr->PROC_NR, (vir_bytes) m_ptr->ADDRESS, size);
12068 if (user_phys == 0) {
12069 tty_reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, EFAULT);
12070 return;
12071 }
12072 }
12073
12074 r = OK;
12075 switch (m_ptr->TTY_REQUEST) {
12076 case TCGETS:
12077 /* Get the termios attributes. */
12078 phys_copy(vir2phys(&tp->tty_termios), user_phys, (phys_bytes) size);
12079 break;
12080
12081 case TCSETSW:
12082 case TCSETSF:
12083 case TCDRAIN:
12084 if (tp->tty_outleft > 0) {
12085 /* Wait for all ongoing output processing to finish. */
12086 tp->tty_iocaller = m_ptr->m_source;
12087 tp->tty_ioproc = m_ptr->PROC_NR;
12088 tp->tty_ioreq = m_ptr->REQUEST;
12089 tp->tty_iovir = (vir_bytes) m_ptr->ADDRESS;
12090 r = SUSPEND;
12091 break;
12092 }
12093 if (m_ptr->TTY_REQUEST == TCDRAIN) break;
12094 if (m_ptr->TTY_REQUEST == TCSETSF) tty_icancel(tp);
12095 /*FALL THROUGH*/
12096 case TCSETS:
12097 /* Set the termios attributes. */
12098 phys_copy(user_phys, vir2phys(&tp->tty_termios), (phys_bytes) size);
12099 setattr(tp);
12100 break;
12101
12102 case TCFLSH:
12103 phys_copy(user_phys, vir2phys(&param.i), (phys_bytes) size);
12104 switch (param.i) {
12105 case TCIFLUSH: tty_icancel(tp); break;
12106 case TCOFLUSH: (*tp->tty_ocancel)(tp); break;
12107 case TCIOFLUSH: tty_icancel(tp); (*tp->tty_ocancel)(tp);break;
12108 default: r = EINVAL;
12109 }
12110 break;
12111
12112 case TCFLOW:
12113 phys_copy(user_phys, vir2phys(&param.i), (phys_bytes) size);
12114 switch (param.i) {
12115 case TCOOFF:
12116 case TCOON:
12117 tp->tty_inhibited = (param.i == TCOOFF);
12118 tp->tty_events = 1;
12119 break;
12120 case TCIOFF:
12121 (*tp->tty_echo)(tp, tp->tty_termios.c_cc[VSTOP]);
12122 break;
12123 case TCION:
12124 (*tp->tty_echo)(tp, tp->tty_termios.c_cc[VSTART]);
12125 break;
12126 default:
12127 r = EINVAL;
12128 }
12129 break;
12130
12131 case TCSBRK:
12132 if (tp->tty_break != NULL) (*tp->tty_break)(tp);
12133 break;
12134
12135 case TIOCGWINSZ:
12136 phys_copy(vir2phys(&tp->tty_winsize), user_phys, (phys_bytes) size);
12137 break;
12138
12139 case TIOCSWINSZ:
12140 phys_copy(user_phys, vir2phys(&tp->tty_winsize), (phys_bytes) size);
12141 /* SIGWINCH... */
12142 break;
12143
12144 case KIOCSMAP:
12145 /* Load a new keymap (only /dev/console). */
12146 if (isconsole(tp)) r = kbd_loadmap(user_phys);
12147 break;
12148
12149 case TIOCSFON:
12150 /* Load a font into an EGA or VGA card (hs@hck.hr) */
12151 if (isconsole(tp)) r = con_loadfont(user_phys);
12152 break;
12153
12154 /* These Posix functions are allowed to fail if _POSIX_JOB_CONTROL is
12155 * not defined.
12156 */
12157 case TIOCGPGRP:
12158 case TIOCSPGRP:
12159 default:
12160 r = ENOTTY;
12161 }
12162
12163 /* Send the reply. */
12164 tty_reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, r);
12165 }
12168 /*===========================================================================*
12169 * do_open *
12170 *===========================================================================*/
12171 PRIVATE void do_open(tp, m_ptr)
12172 register tty_t *tp;
12173 message *m_ptr; /* pointer to message sent to task */
12174 {
12175 /* A tty line has been opened. Make it the callers controlling tty if
12176 * O_NOCTTY is *not* set and it is not the log device. 1 is returned if
12177 * the tty is made the controlling tty, otherwise OK or an error code.
12178 */
12179 int r = OK;
12180
12181 if (m_ptr->TTY_LINE == LOG_MINOR) {
12182 /* The log device is a write-only diagnostics device. */
12183 if (m_ptr->COUNT & R_BIT) r = EACCES;
12184 } else {
12185 if (!(m_ptr->COUNT & O_NOCTTY)) {
12186 tp->tty_pgrp = m_ptr->PROC_NR;
12187 r = 1;
12188 }
12189 tp->tty_openct++;
12190 }
12191 tty_reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, r);
12192 }
12195 /*===========================================================================*
12196 * do_close *
12197 *===========================================================================*/
12198 PRIVATE void do_close(tp, m_ptr)
12199 register tty_t *tp;
12200 message *m_ptr; /* pointer to message sent to task */
12201 {
12202 /* A tty line has been closed. Clean up the line if it is the last close. */
12203
12204 if (m_ptr->TTY_LINE != LOG_MINOR && --tp->tty_openct == 0) {
12205 tp->tty_pgrp = 0;
12206 tty_icancel(tp);
12207 (*tp->tty_ocancel)(tp);
12208 (*tp->tty_close)(tp);
12209 tp->tty_termios = termios_defaults;
12210 tp->tty_winsize = winsize_defaults;
12211 setattr(tp);
12212 }
12213 tty_reply(TASK_REPLY, m_ptr->m_source, m_ptr->PROC_NR, OK);
12214 }
12217 /*===========================================================================*
12218 * do_cancel *
12219 *===========================================================================*/
12220 PRIVATE void do_cancel(tp, m_ptr)
12221 register tty_t *tp;
12222 message *m_ptr; /* pointer to message sent to task */
12223 {
12224 /* A signal has been sent to a process that is hanging trying to read or write.
12225 * The pending read or write must be finished off immediately.
12226 */
12227
12228 int proc_nr;
12229 int mode;
12230
12231 /* Check the parameters carefully, to avoid cancelling twice. */
12232 proc_nr = m_ptr->PROC_NR;
12233 mode = m_ptr->COUNT;
12234 if ((mode & R_BIT) && tp->tty_inleft != 0 && proc_nr == tp->tty_inproc) {
12235 /* Process was reading when killed. Clean up input. */
12236 tty_icancel(tp);
12237 tp->tty_inleft = tp->tty_incum = 0;
12238 }
12239 if ((mode & W_BIT) && tp->tty_outleft != 0 && proc_nr == tp->tty_outproc) {
12240 /* Process was writing when killed. Clean up output. */
12241 (*tp->tty_ocancel)(tp);
12242 tp->tty_outleft = tp->tty_outcum = 0;
12243 }
12244 if (tp->tty_ioreq != 0 && proc_nr == tp->tty_ioproc) {
12245 /* Process was waiting for output to drain. */
12246 tp->tty_ioreq = 0;
12247 }
12248 tp->tty_events = 1;
12249 tty_reply(TASK_REPLY, m_ptr->m_source, proc_nr, EINTR);
12250 }
12253 /*===========================================================================*
12254 * handle_events *
12255 *===========================================================================*/
12256 PUBLIC void handle_events(tp)
12257 tty_t *tp; /* TTY to check for events. */
12258 {
12259 /* Handle any events pending on a TTY. These events are usually device
12260 * interrupts.
12261 *
12262 * Two kinds of events are prominent:
12263 * - a character has been received from the console or an RS232 line.
12264 * - an RS232 line has completed a write request (on behalf of a user).
12265 * The interrupt handler may delay the interrupt message at its discretion
12266 * to avoid swamping the TTY task. Messages may be overwritten when the
12267 * lines are fast or when there are races between different lines, input
12268 * and output, because MINIX only provides single buffering for interrupt
12269 * messages (in proc.c). This is handled by explicitly checking each line
12270 * for fresh input and completed output on each interrupt.
12271 */
12272 char *buf;
12273 unsigned count;
12274
12275 do {
12276 tp->tty_events = 0;
12277
12278 /* Read input and perform input processing. */
12279 (*tp->tty_devread)(tp);
12280
12281 /* Perform output processing and write output. */
12282 (*tp->tty_devwrite)(tp);
12283
12284 /* Ioctl waiting for some event? */
12285 if (tp->tty_ioreq != 0) dev_ioctl(tp);
12286 } while (tp->tty_events);
12287
12288 /* Transfer characters from the input queue to a waiting process. */
12289 in_transfer(tp);
12290
12291 /* Reply if enough bytes are available. */
12292 if (tp->tty_incum >= tp->tty_min && tp->tty_inleft > 0) {
12293 tty_reply(tp->tty_inrepcode, tp->tty_incaller, tp->tty_inproc,
12294 tp->tty_incum);
12295 tp->tty_inleft = tp->tty_incum = 0;
12296 }
12297 }
12300 /*===========================================================================*
12301 * in_transfer *
12302 *===========================================================================*/
12303 PRIVATE void in_transfer(tp)
12304 register tty_t *tp; /* pointer to terminal to read from */
12305 {
12306 /* Transfer bytes from the input queue to a process reading from a terminal. */
12307
12308 int ch;
12309 int count;
12310 phys_bytes buf_phys, user_base;
12311 char buf[64], *bp;
12312
12313 /* Anything to do? */
12314 if (tp->tty_inleft == 0 || tp->tty_eotct < tp->tty_min) return;
12315
12316 buf_phys = vir2phys(buf);
12317 user_base = proc_vir2phys(proc_addr(tp->tty_inproc), 0);
12318 bp = buf;
12319 while (tp->tty_inleft > 0 && tp->tty_eotct > 0) {
12320 ch = *tp->tty_intail;
12321
12322 if (!(ch & IN_EOF)) {
12323 /* One character to be delivered to the user. */
12324 *bp = ch & IN_CHAR;
12325 tp->tty_inleft--;
12326 if (++bp == bufend(buf)) {
12327 /* Temp buffer full, copy to user space. */
12328 phys_copy(buf_phys, user_base + tp->tty_in_vir,
12329 (phys_bytes) buflen(buf));
12330 tp->tty_in_vir += buflen(buf);
12331 tp->tty_incum += buflen(buf);
12332 bp = buf;
12333 }
12334 }
12335
12336 /* Remove the character from the input queue. */
12337 if (++tp->tty_intail == bufend(tp->tty_inbuf))
12338 tp->tty_intail = tp->tty_inbuf;
12339 tp->tty_incount--;
12340 if (ch & IN_EOT) {
12341 tp->tty_eotct--;
12342 /* Don't read past a line break in canonical mode. */
12343 if (tp->tty_termios.c_lflag & ICANON) tp->tty_inleft = 0;
12344 }
12345 }
12346
12347 if (bp > buf) {
12348 /* Leftover characters in the buffer. */
12349 count = bp - buf;
12350 phys_copy(buf_phys, user_base + tp->tty_in_vir, (phys_bytes) count);
12351 tp->tty_in_vir += count;
12352 tp->tty_incum += count;
12353 }
12354
12355 /* Usually reply to the reader, possibly even if incum == 0 (EOF). */
12356 if (tp->tty_inleft == 0) {
12357 tty_reply(tp->tty_inrepcode, tp->tty_incaller, tp->tty_inproc,
12358 tp->tty_incum);
12359 tp->tty_inleft = tp->tty_incum = 0;
12360 }
12361 }
12364 /*===========================================================================*
12365 * in_process *
12366 *===========================================================================*/
12367 PUBLIC int in_process(tp, buf, count)
12368 register tty_t *tp; /* terminal on which character has arrived */
12369 char *buf; /* buffer with input characters */
12370 int count; /* number of input characters */
12371 {
12372 /* Characters have just been typed in. Process, save, and echo them. Return
12373 * the number of characters processed.
12374 */
12375
12376 int ch, sig, ct;
12377 int timeset = FALSE;
12378 static unsigned char csize_mask[] = { 0x1F, 0x3F, 0x7F, 0xFF };
12379
12380 for (ct = 0; ct < count; ct++) {
12381 /* Take one character. */
12382 ch = *buf++ & BYTE;
12383
12384 /* Strip to seven bits? */
12385 if (tp->tty_termios.c_iflag & ISTRIP) ch &= 0x7F;
12386
12387 /* Input extensions? */
12388 if (tp->tty_termios.c_lflag & IEXTEN) {
12389
12390 /* Previous character was a character escape? */
12391 if (tp->tty_escaped) {
12392 tp->tty_escaped = NOT_ESCAPED;
12393 ch |= IN_ESC; /* protect character */
12394 }
12395
12396 /* LNEXT (^V) to escape the next character? */
12397 if (ch == tp->tty_termios.c_cc[VLNEXT]) {
12398 tp->tty_escaped = ESCAPED;
12399 rawecho(tp, '^');
12400 rawecho(tp, 'b');
12401 continue; /* do not store the escape */
12402 }
12403
12404 /* REPRINT (^R) to reprint echoed characters? */
12405 if (ch == tp->tty_termios.c_cc[VREPRINT]) {
12406 reprint(tp);
12407 continue;
12408 }
12409 }
12410
12411 /* _POSIX_VDISABLE is a normal character value, so better escape it. */
12412 if (ch == _POSIX_VDISABLE) ch |= IN_ESC;
12413
12414 /* Map CR to LF, ignore CR, or map LF to CR. */
12415 if (ch == 'r') {
12416 if (tp->tty_termios.c_iflag & IGNCR) continue;
12417 if (tp->tty_termios.c_iflag & ICRNL) ch = 'n';
12418 } else
12419 if (ch == 'n') {
12420 if (tp->tty_termios.c_iflag & INLCR) ch = 'r';
12421 }
12422
12423 /* Canonical mode? */
12424 if (tp->tty_termios.c_lflag & ICANON) {
12425
12426 /* Erase processing (rub out of last character). */
12427 if (ch == tp->tty_termios.c_cc[VERASE]) {
12428 (void) back_over(tp);
12429 if (!(tp->tty_termios.c_lflag & ECHOE)) {
12430 (void) echo(tp, ch);
12431 }
12432 continue;
12433 }
12434
12435 /* Kill processing (remove current line). */
12436 if (ch == tp->tty_termios.c_cc[VKILL]) {
12437 while (back_over(tp)) {}
12438 if (!(tp->tty_termios.c_lflag & ECHOE)) {
12439 (void) echo(tp, ch);
12440 if (tp->tty_termios.c_lflag & ECHOK)
12441 rawecho(tp, 'n');
12442 }
12443 continue;
12444 }
12445
12446 /* EOF (^D) means end-of-file, an invisible "line break". */
12447 if (ch == tp->tty_termios.c_cc[VEOF]) ch |= IN_EOT | IN_EOF;
12448
12449 /* The line may be returned to the user after an LF. */
12450 if (ch == 'n') ch |= IN_EOT;
12451
12452 /* Same thing with EOL, whatever it may be. */
12453 if (ch == tp->tty_termios.c_cc[VEOL]) ch |= IN_EOT;
12454 }
12455
12456 /* Start/stop input control? */
12457 if (tp->tty_termios.c_iflag & IXON) {
12458
12459 /* Output stops on STOP (^S). */
12460 if (ch == tp->tty_termios.c_cc[VSTOP]) {
12461 tp->tty_inhibited = STOPPED;
12462 tp->tty_events = 1;
12463 continue;
12464 }
12465
12466 /* Output restarts on START (^Q) or any character if IXANY. */
12467 if (tp->tty_inhibited) {
12468 if (ch == tp->tty_termios.c_cc[VSTART]
12469 || (tp->tty_termios.c_iflag & IXANY)) {
12470 tp->tty_inhibited = RUNNING;
12471 tp->tty_events = 1;
12472 if (ch == tp->tty_termios.c_cc[VSTART])
12473 continue;
12474 }
12475 }
12476 }
12477
12478 if (tp->tty_termios.c_lflag & ISIG) {
12479 /* Check for INTR (^?) and QUIT (^) characters. */
12480 if (ch == tp->tty_termios.c_cc[VINTR]
12481 || ch == tp->tty_termios.c_cc[VQUIT]) {
12482 sig = SIGINT;
12483 if (ch == tp->tty_termios.c_cc[VQUIT]) sig = SIGQUIT;
12484 sigchar(tp, sig);
12485 (void) echo(tp, ch);
12486 continue;
12487 }
12488 }
12489
12490 /* Is there space in the input buffer? */
12491 if (tp->tty_incount == buflen(tp->tty_inbuf)) {
12492 /* No space; discard in canonical mode, keep in raw mode. */
12493 if (tp->tty_termios.c_lflag & ICANON) continue;
12494 break;
12495 }
12496
12497 if (!(tp->tty_termios.c_lflag & ICANON)) {
12498 /* In raw mode all characters are "line breaks". */
12499 ch |= IN_EOT;
12500
12501 /* Start an inter-byte timer? */
12502 if (!timeset && tp->tty_termios.c_cc[VMIN] > 0
12503 && tp->tty_termios.c_cc[VTIME] > 0) {
12504 lock();
12505 settimer(tp, TRUE);
12506 unlock();
12507 timeset = TRUE;
12508 }
12509 }
12510
12511 /* Perform the intricate function of echoing. */
12512 if (tp->tty_termios.c_lflag & (ECHO|ECHONL)) ch = echo(tp, ch);
12513
12514 /* Save the character in the input queue. */
12515 *tp->tty_inhead++ = ch;
12516 if (tp->tty_inhead == bufend(tp->tty_inbuf))
12517 tp->tty_inhead = tp->tty_inbuf;
12518 tp->tty_incount++;
12519 if (ch & IN_EOT) tp->tty_eotct++;
12520
12521 /* Try to finish input if the queue threatens to overflow. */
12522 if (tp->tty_incount == buflen(tp->tty_inbuf)) in_transfer(tp);
12523 }
12524 return ct;
12525 }
12528 /*===========================================================================*
12529 * echo *
12530 *===========================================================================*/
12531 PRIVATE int echo(tp, ch)
12532 register tty_t *tp; /* terminal on which to echo */
12533 register int ch; /* pointer to character to echo */
12534 {
12535 /* Echo the character if echoing is on. Some control characters are echoed
12536 * with their normal effect, other control characters are echoed as "^X",
12537 * normal characters are echoed normally. EOF (^D) is echoed, but immediately
12538 * backspaced over. Return the character with the echoed length added to its
12539 * attributes.
12540 */
12541 int len, rp;
12542
12543 ch &= ~IN_LEN;
12544 if (!(tp->tty_termios.c_lflag & ECHO)) {
12545 if (ch == ('n' | IN_EOT) && (tp->tty_termios.c_lflag
12546 & (ICANON|ECHONL)) == (ICANON|ECHONL))
12547 (*tp->tty_echo)(tp, 'n');
12548 return(ch);
12549 }
12550
12551 /* "Reprint" tells if the echo output has been messed up by other output. */
12552 rp = tp->tty_incount == 0 ? FALSE : tp->tty_reprint;
12553
12554 if ((ch & IN_CHAR) < ' ') {
12555 switch (ch & (IN_ESC|IN_EOF|IN_EOT|IN_CHAR)) {
12556 case 't':
12557 len = 0;
12558 do {
12559 (*tp->tty_echo)(tp, ' ');
12560 len++;
12561 } while (len < TAB_SIZE && (tp->tty_position & TAB_MASK) != 0);
12562 break;
12563 case 'r' | IN_EOT:
12564 case 'n' | IN_EOT:
12565 (*tp->tty_echo)(tp, ch & IN_CHAR);
12566 len = 0;
12567 break;
12568 default:
12569 (*tp->tty_echo)(tp, '^');
12570 (*tp->tty_echo)(tp, '@' + (ch & IN_CHAR));
12571 len = 2;
12572 }
12573 } else
12574 if ((ch & IN_CHAR) == '177') {
12575 /* A DEL prints as "^?". */
12576 (*tp->tty_echo)(tp, '^');
12577 (*tp->tty_echo)(tp, '?');
12578 len = 2;
12579 } else {
12580 (*tp->tty_echo)(tp, ch & IN_CHAR);
12581 len = 1;
12582 }
12583 if (ch & IN_EOF) while (len > 0) { (*tp->tty_echo)(tp, 'b'); len--; }
12584
12585 tp->tty_reprint = rp;
12586 return(ch | (len << IN_LSHIFT));
12587 }
12590 /*==========================================================================*
12591 * rawecho *
12592 *==========================================================================*/
12593 PRIVATE void rawecho(tp, ch)
12594 register tty_t *tp;
12595 int ch;
12596 {
12597 /* Echo without interpretation if ECHO is set. */
12598 int rp = tp->tty_reprint;
12599 if (tp->tty_termios.c_lflag & ECHO) (*tp->tty_echo)(tp, ch);
12600 tp->tty_reprint = rp;
12601 }
12604 /*==========================================================================*
12605 * back_over *
12606 *==========================================================================*/
12607 PRIVATE int back_over(tp)
12608 register tty_t *tp;
12609 {
12610 /* Backspace to previous character on screen and erase it. */
12611 u16_t *head;
12612 int len;
12613
12614 if (tp->tty_incount == 0) return(0); /* queue empty */
12615 head = tp->tty_inhead;
12616 if (head == tp->tty_inbuf) head = bufend(tp->tty_inbuf);
12617 if (*--head & IN_EOT) return(0); /* can't erase "line breaks" */
12618 if (tp->tty_reprint) reprint(tp); /* reprint if messed up */
12619 tp->tty_inhead = head;
12620 tp->tty_incount--;
12621 if (tp->tty_termios.c_lflag & ECHOE) {
12622 len = (*head & IN_LEN) >> IN_LSHIFT;
12623 while (len > 0) {
12624 rawecho(tp, 'b');
12625 rawecho(tp, ' ');
12626 rawecho(tp, 'b');
12627 len--;
12628 }
12629 }
12630 return(1); /* one character erased */
12631 }
12634 /*==========================================================================*
12635 * reprint *
12636 *==========================================================================*/
12637 PRIVATE void reprint(tp)
12638 register tty_t *tp; /* pointer to tty struct */
12639 {
12640 /* Restore what has been echoed to screen before if the user input has been
12641 * messed up by output, or if REPRINT (^R) is typed.
12642 */
12643 int count;
12644 u16_t *head;
12645
12646 tp->tty_reprint = FALSE;
12647
12648 /* Find the last line break in the input. */
12649 head = tp->tty_inhead;
12650 count = tp->tty_incount;
12651 while (count > 0) {
12652 if (head == tp->tty_inbuf) head = bufend(tp->tty_inbuf);
12653 if (head[-1] & IN_EOT) break;
12654 head--;
12655 count--;
12656 }
12657 if (count == tp->tty_incount) return; /* no reason to reprint */
12658
12659 /* Show REPRINT (^R) and move to a new line. */
12660 (void) echo(tp, tp->tty_termios.c_cc[VREPRINT] | IN_ESC);
12661 rawecho(tp, 'r');
12662 rawecho(tp, 'n');
12663
12664 /* Reprint from the last break onwards. */
12665 do {
12666 if (head == bufend(tp->tty_inbuf)) head = tp->tty_inbuf;
12667 *head = echo(tp, *head);
12668 head++;
12669 count++;
12670 } while (count < tp->tty_incount);
12671 }
12674 /*==========================================================================*
12675 * out_process *
12676 *==========================================================================*/
12677 PUBLIC void out_process(tp, bstart, bpos, bend, icount, ocount)
12678 tty_t *tp;
12679 char *bstart, *bpos, *bend; /* start/pos/end of circular buffer */
12680 int *icount; /* # input chars / input chars used */
12681 int *ocount; /* max output chars / output chars used */
12682 {
12683 /* Perform output processing on a circular buffer. *icount is the number of
12684 * bytes to process, and the number of bytes actually processed on return.
12685 * *ocount is the space available on input and the space used on output.
12686 * (Naturally *icount < *ocount.) The column position is updated modulo
12687 * the TAB size, because we really only need it for tabs.
12688 */
12689
12690 int tablen;
12691 int ict = *icount;
12692 int oct = *ocount;
12693 int pos = tp->tty_position;
12694
12695 while (ict > 0) {
12696 switch (*bpos) {
12697 case '7':
12698 break;
12699 case 'b':
12700 pos--;
12701 break;
12702 case 'r':
12703 pos = 0;
12704 break;
12705 case 'n':
12706 if ((tp->tty_termios.c_oflag & (OPOST|ONLCR))
12707 == (OPOST|ONLCR)) {
12708 /* Map LF to CR+LF if there is space. Note that the
12709 * next character in the buffer is overwritten, so
12710 * we stop at this point.
12711 */
12712 if (oct >= 2) {
12713 *bpos = 'r';
12714 if (++bpos == bend) bpos = bstart;
12715 *bpos = 'n';
12716 pos = 0;
12717 ict--;
12718 oct -= 2;
12719 }
12720 goto out_done; /* no space or buffer got changed */
12721 }
12722 break;
12723 case 't':
12724 /* Best guess for the tab length. */
12725 tablen = TAB_SIZE - (pos & TAB_MASK);
12726
12727 if ((tp->tty_termios.c_oflag & (OPOST|XTABS))
12728 == (OPOST|XTABS)) {
12729 /* Tabs must be expanded. */
12730 if (oct >= tablen) {
12731 pos += tablen;
12732 ict--;
12733 oct -= tablen;
12734 do {
12735 *bpos = ' ';
12736 if (++bpos == bend) bpos = bstart;
12737 } while (--tablen != 0);
12738 }
12739 goto out_done;
12740 }
12741 /* Tabs are output directly. */
12742 pos += tablen;
12743 break;
12744 default:
12745 /* Assume any other character prints as one character. */
12746 pos++;
12747 }
12748 if (++bpos == bend) bpos = bstart;
12749 ict--;
12750 oct--;
12751 }
12752 out_done:
12753 tp->tty_position = pos & TAB_MASK;
12754
12755 *icount -= ict; /* [io]ct are the number of chars not used */
12756 *ocount -= oct; /* *[io]count are the number of chars that are used */
12757 }
12760 /*===========================================================================*
12761 * dev_ioctl *
12762 *===========================================================================*/
12763 PRIVATE void dev_ioctl(tp)
12764 tty_t *tp;
12765 {
12766 /* The ioctl's TCSETSW, TCSETSF and TCDRAIN wait for output to finish to make
12767 * sure that an attribute change doesn't affect the processing of current
12768 * output. Once output finishes the ioctl is executed as in do_ioctl().
12769 */
12770 phys_bytes user_phys;
12771
12772 if (tp->tty_outleft > 0) return; /* output not finished */
12773
12774 if (tp->tty_ioreq != TCDRAIN) {
12775 if (tp->tty_ioreq == TCSETSF) tty_icancel(tp);
12776 user_phys = proc_vir2phys(proc_addr(tp->tty_ioproc), tp->tty_iovir);
12777 phys_copy(user_phys, vir2phys(&tp->tty_termios),
12778 (phys_bytes) sizeof(tp->tty_termios));
12779 setattr(tp);
12780 }
12781 tp->tty_ioreq = 0;
12782 tty_reply(REVIVE, tp->tty_iocaller, tp->tty_ioproc, OK);
12783 }
12786 /*===========================================================================*
12787 * setattr *
12788 *===========================================================================*/
12789 PRIVATE void setattr(tp)
12790 tty_t *tp;
12791 {
12792 /* Apply the new line attributes (raw/canonical, line speed, etc.) */
12793 u16_t *inp;
12794 int count;
12795
12796 if (!(tp->tty_termios.c_lflag & ICANON)) {
12797 /* Raw mode; put a "line break" on all characters in the input queue.
12798 * It is undefined what happens to the input queue when ICANON is
12799 * switched off, a process should use TCSAFLUSH to flush the queue.
12800 * Keeping the queue to preserve typeahead is the Right Thing, however
12801 * when a process does use TCSANOW to switch to raw mode.
12802 */
12803 count = tp->tty_eotct = tp->tty_incount;
12804 inp = tp->tty_intail;
12805 while (count > 0) {
12806 *inp |= IN_EOT;
12807 if (++inp == bufend(tp->tty_inbuf)) inp = tp->tty_inbuf;
12808 --count;
12809 }
12810 }
12811
12812 /* Inspect MIN and TIME. */
12813 lock();
12814 settimer(tp, FALSE);
12815 unlock();
12816 if (tp->tty_termios.c_lflag & ICANON) {
12817 /* No MIN & TIME in canonical mode. */
12818 tp->tty_min = 1;
12819 } else {
12820 /* In raw mode MIN is the number of chars wanted, and TIME how long
12821 * to wait for them. With interesting exceptions if either is zero.
12822 */
12823 tp->tty_min = tp->tty_termios.c_cc[VMIN];
12824 if (tp->tty_min == 0 && tp->tty_termios.c_cc[VTIME] > 0)
12825 tp->tty_min = 1;
12826 }
12827
12828 if (!(tp->tty_termios.c_iflag & IXON)) {
12829 /* No start/stop output control, so don't leave output inhibited. */
12830 tp->tty_inhibited = RUNNING;
12831 tp->tty_events = 1;
12832 }
12833
12834 /* Setting the output speed to zero hangs up the phone. */
12835 if (tp->tty_termios.c_ospeed == B0) sigchar(tp, SIGHUP);
12836
12837 /* Set new line speed, character size, etc at the device level. */
12838 (*tp->tty_ioctl)(tp);
12839 }
12842 /*===========================================================================*
12843 * tty_reply *
12844 *===========================================================================*/
12845 PUBLIC void tty_reply(code, replyee, proc_nr, status)
12846 int code; /* TASK_REPLY or REVIVE */
12847 int replyee; /* destination address for the reply */
12848 int proc_nr; /* to whom should the reply go? */
12849 int status; /* reply code */
12850 {
12851 /* Send a reply to a process that wanted to read or write data. */
12852
12853 message tty_mess;
12854
12855 tty_mess.m_type = code;
12856 tty_mess.REP_PROC_NR = proc_nr;
12857 tty_mess.REP_STATUS = status;
12858 if ((status = send(replyee, &tty_mess)) != OK)
12859 panic("tty_reply failed, statusn", status);
12860 }
12863 /*===========================================================================*
12864 * sigchar *
12865 *===========================================================================*/
12866 PUBLIC void sigchar(tp, sig)
12867 register tty_t *tp;
12868 int sig; /* SIGINT, SIGQUIT, SIGKILL or SIGHUP */
12869 {
12870 /* Process a SIGINT, SIGQUIT or SIGKILL char from the keyboard or SIGHUP from
12871 * a tty close, "stty 0", or a real RS-232 hangup. MM will send the signal to
12872 * the process group (INT, QUIT), all processes (KILL), or the session leader
12873 * (HUP).
12874 */
12875
12876 if (tp->tty_pgrp != 0) cause_sig(tp->tty_pgrp, sig);
12877
12878 if (!(tp->tty_termios.c_lflag & NOFLSH)) {
12879 tp->tty_incount = tp->tty_eotct = 0; /* kill earlier input */
12880 tp->tty_intail = tp->tty_inhead;
12881 (*tp->tty_ocancel)(tp); /* kill all output */
12882 tp->tty_inhibited = RUNNING;
12883 tp->tty_events = 1;
12884 }
12885 }
12888 /*==========================================================================*
12889 * tty_icancel *
12890 *==========================================================================*/
12891 PRIVATE void tty_icancel(tp)
12892 register tty_t *tp;
12893 {
12894 /* Discard all pending input, tty buffer or device. */
12895
12896 tp->tty_incount = tp->tty_eotct = 0;
12897 tp->tty_intail = tp->tty_inhead;
12898 (*tp->tty_icancel)(tp);
12899 }
12902 /*==========================================================================*
12903 * tty_init *
12904 *==========================================================================*/
12905 PRIVATE void tty_init(tp)
12906 tty_t *tp; /* TTY line to initialize. */
12907 {
12908 /* Initialize tty structure and call device initialization routines. */
12909
12910 tp->tty_intail = tp->tty_inhead = tp->tty_inbuf;
12911 tp->tty_min = 1;
12912 tp->tty_termios = termios_defaults;
12913 tp->tty_icancel = tp->tty_ocancel = tp->tty_ioctl = tp->tty_close =
12914 tty_devnop;
12915 if (tp < tty_addr(NR_CONS)) {
12916 scr_init(tp);
12917 } else
12918 if (tp < tty_addr(NR_CONS+NR_RS_LINES)) {
12919 rs_init(tp);
12920 } else {
12921 pty_init(tp);
12922 }
12923 }
12926 /*==========================================================================*
12927 * tty_wakeup *
12928 *==========================================================================*/
12929 PUBLIC void tty_wakeup(now)
12930 clock_t now; /* current time */
12931 {
12932 /* Wake up TTY when something interesting is happening on one of the terminal
12933 * lines, like a character arriving on an RS232 line, a key being typed, or
12934 * a timer on a line expiring by TIME.
12935 */
12936 tty_t *tp;
12937
12938 /* Scan the timerlist for expired timers and compute the next timeout time. */
12939 tty_timeout = TIME_NEVER;
12940 while ((tp = tty_timelist) != NULL) {
12941 if (tp->tty_time > now) {
12942 tty_timeout = tp->tty_time; /* this timer is next */
12943 break;
12944 }
12945 tp->tty_min = 0; /* force read to succeed */
12946 tp->tty_events = 1;
12947 tty_timelist = tp->tty_timenext;
12948 }
12949
12950 /* Let TTY know there is something afoot. */
12951 interrupt(TTY);
12952 }
12955 /*===========================================================================*
12956 * settimer *
12957 *===========================================================================*/
12958 PRIVATE void settimer(tp, on)
12959 tty_t *tp; /* line to set or unset a timer on */
12960 int on; /* set timer if true, otherwise unset */
12961 {
12962 /* Set or unset a TIME inspired timer. This function is interrupt sensitive
12963 * due to tty_wakeup(), so it must be called from within lock()/unlock().
12964 */
12965 tty_t **ptp;
12966
12967 /* Take tp out of the timerlist if present. */
12968 for (ptp = &tty_timelist; *ptp != NULL; ptp = &(*ptp)->tty_timenext) {
12969 if (tp == *ptp) {
12970 *ptp = tp->tty_timenext; /* take tp out of the list */
12971 break;
12972 }
12973 }
12974 if (!on) return; /* unsetting it is enough */
12975
12976 /* Timeout occurs TIME deciseconds from now. */
12977 tp->tty_time = get_uptime() + tp->tty_termios.c_cc[VTIME] * (HZ/10);
12978
12979 /* Find a new place in the list. */
12980 for (ptp = &tty_timelist; *ptp != NULL; ptp = &(*ptp)->tty_timenext) {
12981 if (tp->tty_time <= (*ptp)->tty_time) break;
12982 }
12983 tp->tty_timenext = *ptp;
12984 *ptp = tp;
12985 if (tp->tty_time < tty_timeout) tty_timeout = tp->tty_time;
12986 }
12989 /*==========================================================================*
12990 * tty_devnop *
12991 *==========================================================================*/
12992 PUBLIC void tty_devnop(tp)
12993 tty_t *tp;
12994 {
12995 /* Some functions need not be implemented at the device level. */
12996 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/keyboard.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
13000 /* Keyboard driver for PC's and AT's.
13001 *
13002 * Changed by Marcus Hampel (04/02/1994)
13003 * - Loadable keymaps
13004 */
13005
13006 #include "kernel.h"
13007 #include <termios.h>
13008 #include <signal.h>
13009 #include <unistd.h>
13010 #include <minix/callnr.h>
13011 #include <minix/com.h>
13012 #include <minix/keymap.h>
13013 #include "tty.h"
13014 #include "keymaps/us-std.src"
13015
13016 /* Standard and AT keyboard. (PS/2 MCA implies AT throughout.) */
13017 #define KEYBD 0x60 /* I/O port for keyboard data */
13018
13019 /* AT keyboard. */
13020 #define KB_COMMAND 0x64 /* I/O port for commands on AT */
13021 #define KB_GATE_A20 0x02 /* bit in output port to enable A20 line */
13022 #define KB_PULSE_OUTPUT 0xF0 /* base for commands to pulse output port */
13023 #define KB_RESET 0x01 /* bit in output port to reset CPU */
13024 #define KB_STATUS 0x64 /* I/O port for status on AT */
13025 #define KB_ACK 0xFA /* keyboard ack response */
13026 #define KB_BUSY 0x02 /* status bit set when KEYBD port ready */
13027 #define LED_CODE 0xED /* command to keyboard to set LEDs */
13028 #define MAX_KB_ACK_RETRIES 0x1000 /* max #times to wait for kb ack */
13029 #define MAX_KB_BUSY_RETRIES 0x1000 /* max #times to loop while kb busy */
13030 #define KBIT 0x80 /* bit used to ack characters to keyboard */
13031
13032 /* Miscellaneous. */
13033 #define ESC_SCAN 1 /* Reboot key when panicking */
13034 #define SLASH_SCAN 53 /* to recognize numeric slash */
13035 #define HOME_SCAN 71 /* first key on the numeric keypad */
13036 #define DEL_SCAN 83 /* DEL for use in CTRL-ALT-DEL reboot */
13037 #define CONSOLE 0 /* line number for console */
13038 #define MEMCHECK_ADR 0x472 /* address to stop memory check after reboot */
13039 #define MEMCHECK_MAG 0x1234 /* magic number to stop memory check */
13040
13041 #define kb_addr() (&kb_lines[0]) /* there is only one keyboard */
13042 #define KB_IN_BYTES 32 /* size of keyboard input buffer */
13043
13044 PRIVATE int alt1; /* left alt key state */
13045 PRIVATE int alt2; /* right alt key state */
13046 PRIVATE int capslock; /* caps lock key state */
13047 PRIVATE int esc; /* escape scan code detected? */
13048 PRIVATE int control; /* control key state */
13049 PRIVATE int caps_off; /* 1 = normal position, 0 = depressed */
13050 PRIVATE int numlock; /* number lock key state */
13051 PRIVATE int num_off; /* 1 = normal position, 0 = depressed */
13052 PRIVATE int slock; /* scroll lock key state */
13053 PRIVATE int slock_off; /* 1 = normal position, 0 = depressed */
13054 PRIVATE int shift; /* shift key state */
13055
13056 PRIVATE char numpad_map[] =
13057 {'H', 'Y', 'A', 'B', 'D', 'C', 'V', 'U', 'G', 'S', 'T', '@'};
13058
13059 /* Keyboard structure, 1 per console. */
13060 struct kb_s {
13061 char *ihead; /* next free spot in input buffer */
13062 char *itail; /* scan code to return to TTY */
13063 int icount; /* # codes in buffer */
13064 char ibuf[KB_IN_BYTES]; /* input buffer */
13065 };
13066
13067 PRIVATE struct kb_s kb_lines[NR_CONS];
13068
13069 FORWARD _PROTOTYPE( int kb_ack, (void) );
13070 FORWARD _PROTOTYPE( int kb_wait, (void) );
13071 FORWARD _PROTOTYPE( int func_key, (int scode) );
13072 FORWARD _PROTOTYPE( int scan_keyboard, (void) );
13073 FORWARD _PROTOTYPE( unsigned make_break, (int scode) );
13074 FORWARD _PROTOTYPE( void set_leds, (void) );
13075 FORWARD _PROTOTYPE( int kbd_hw_int, (int irq) );
13076 FORWARD _PROTOTYPE( void kb_read, (struct tty *tp) );
13077 FORWARD _PROTOTYPE( unsigned map_key, (int scode) );
13078
13079
13080 /*===========================================================================*
13081 * map_key0 *
13082 *===========================================================================*/
13083 /* Map a scan code to an ASCII code ignoring modifiers. */
13084 #define map_key0(scode)
13085 ((unsigned) keymap[(scode) * MAP_COLS])
13086
13087
13088 /*===========================================================================*
13089 * map_key *
13090 *===========================================================================*/
13091 PRIVATE unsigned map_key(scode)
13092 int scode;
13093 {
13094 /* Map a scan code to an ASCII code. */
13095
13096 int caps, column;
13097 u16_t *keyrow;
13098
13099 if (scode == SLASH_SCAN && esc) return '/'; /* don't map numeric slash */
13100
13101 keyrow = &keymap[scode * MAP_COLS];
13102
13103 caps = shift;
13104 if (numlock && HOME_SCAN <= scode && scode <= DEL_SCAN) caps = !caps;
13105 if (capslock && (keyrow[0] & HASCAPS)) caps = !caps;
13106
13107 if (alt1 || alt2) {
13108 column = 2;
13109 if (control || alt2) column = 3; /* Ctrl + Alt1 == Alt2 */
13110 if (caps) column = 4;
13111 } else {
13112 column = 0;
13113 if (caps) column = 1;
13114 if (control) column = 5;
13115 }
13116 return keyrow[column] & ~HASCAPS;
13117 }
13120 /*===========================================================================*
13121 * kbd_hw_int *
13122 *===========================================================================*/
13123 PRIVATE int kbd_hw_int(irq)
13124 int irq;
13125 {
13126 /* A keyboard interrupt has occurred. Process it. */
13127
13128 int code;
13129 unsigned km;
13130 register struct kb_s *kb;
13131
13132 /* Fetch the character from the keyboard hardware and acknowledge it. */
13133 code = scan_keyboard();
13134
13135 /* The IBM keyboard interrupts twice per key, once when depressed, once when
13136 * released. Filter out the latter, ignoring all but the shift-type keys.
13137 * The shift-type keys 29, 42, 54, 56, 58, and 69 must be processed normally.
13138 */
13139
13140 if (code & 0200) {
13141 /* A key has been released (high bit is set). */
13142 km = map_key0(code & 0177);
13143 if (km != CTRL && km != SHIFT && km != ALT && km != CALOCK
13144 && km != NLOCK && km != SLOCK && km != EXTKEY)
13145 return 1;
13146 }
13147
13148 /* Store the character in memory so the task can get at it later. */
13149 kb = kb_addr();
13150 if (kb->icount < KB_IN_BYTES) {
13151 *kb->ihead++ = code;
13152 if (kb->ihead == kb->ibuf + KB_IN_BYTES) kb->ihead = kb->ibuf;
13153 kb->icount++;
13154 tty_table[current].tty_events = 1;
13155 force_timeout();
13156 }
13157 /* Else it doesn't fit - discard it. */
13158 return 1; /* Reenable keyboard interrupt */
13159 }
13162 /*==========================================================================*
13163 * kb_read *
13164 *==========================================================================*/
13165 PRIVATE void kb_read(tp)
13166 tty_t *tp;
13167 {
13168 /* Process characters from the circular keyboard buffer. */
13169
13170 struct kb_s *kb;
13171 char buf[3];
13172 int scode;
13173 unsigned ch;
13174
13175 kb = kb_addr();
13176 tp = &tty_table[current]; /* always use the current console */
13177
13178 while (kb->icount > 0) {
13179 scode = *kb->itail++; /* take one key scan code */
13180 if (kb->itail == kb->ibuf + KB_IN_BYTES) kb->itail = kb->ibuf;
13181 lock();
13182 kb->icount--;
13183 unlock();
13184
13185 /* Function keys are being used for debug dumps. */
13186 if (func_key(scode)) continue;
13187
13188 /* Perform make/break processing. */
13189 ch = make_break(scode);
13190
13191 if (ch <= 0xFF) {
13192 /* A normal character. */
13193 buf[0] = ch;
13194 (void) in_process(tp, buf, 1);
13195 } else
13196 if (HOME <= ch && ch <= INSRT) {
13197 /* An ASCII escape sequence generated by the numeric pad. */
13198 buf[0] = ESC;
13199 buf[1] = '[';
13200 buf[2] = numpad_map[ch - HOME];
13201 (void) in_process(tp, buf, 3);
13202 } else
13203 if (ch == ALEFT) {
13204 /* Choose lower numbered console as current console. */
13205 select_console(current - 1);
13206 } else
13207 if (ch == ARIGHT) {
13208 /* Choose higher numbered console as current console. */
13209 select_console(current + 1);
13210 } else
13211 if (AF1 <= ch && ch <= AF12) {
13212 /* Alt-F1 is console, Alt-F2 is ttyc1, etc. */
13213 select_console(ch - AF1);
13214 }
13215 }
13216 }
13219 /*===========================================================================*
13220 * make_break *
13221 *===========================================================================*/
13222 PRIVATE unsigned make_break(scode)
13223 int scode; /* scan code of key just struck or released */
13224 {
13225 /* This routine can handle keyboards that interrupt only on key depression,
13226 * as well as keyboards that interrupt on key depression and key release.
13227 * For efficiency, the interrupt routine filters out most key releases.
13228 */
13229 int ch, make;
13230 static int CAD_count = 0;
13231
13232 /* Check for CTRL-ALT-DEL, and if found, halt the computer. This would
13233 * be better done in keyboard() in case TTY is hung, except control and
13234 * alt are set in the high level code.
13235 */
13236 if (control && (alt1 || alt2) && scode == DEL_SCAN)
13237 {
13238 if (++CAD_count == 3) wreboot(RBT_HALT);
13239 cause_sig(INIT_PROC_NR, SIGABRT);
13240 return -1;
13241 }
13242
13243 /* High-order bit set on key release. */
13244 make = (scode & 0200 ? 0 : 1); /* 0 = release, 1 = press */
13245
13246 ch = map_key(scode & 0177); /* map to ASCII */
13247
13248 switch (ch) {
13249 case CTRL:
13250 control = make;
13251 ch = -1;
13252 break;
13253 case SHIFT:
13254 shift = make;
13255 ch = -1;
13256 break;
13257 case ALT:
13258 if (make) {
13259 if (esc) alt2 = 1; else alt1 = 1;
13260 } else {
13261 alt1 = alt2 = 0;
13262 }
13263 ch = -1;
13264 break;
13265 case CALOCK:
13266 if (make && caps_off) {
13267 capslock = 1 - capslock;
13268 set_leds();
13269 }
13270 caps_off = 1 - make;
13271 ch = -1;
13272 break;
13273 case NLOCK:
13274 if (make && num_off) {
13275 numlock = 1 - numlock;
13276 set_leds();
13277 }
13278 num_off = 1 - make;
13279 ch = -1;
13280 break;
13281 case SLOCK:
13282 if (make & slock_off) {
13283 slock = 1 - slock;
13284 set_leds();
13285 }
13286 slock_off = 1 - make;
13287 ch = -1;
13288 break;
13289 case EXTKEY:
13290 esc = 1;
13291 return(-1);
13292 default:
13293 if (!make) ch = -1;
13294 }
13295 esc = 0;
13296 return(ch);
13297 }
13300 /*===========================================================================*
13301 * set_leds *
13302 *===========================================================================*/
13303 PRIVATE void set_leds()
13304 {
13305 /* Set the LEDs on the caps lock and num lock keys */
13306
13307 unsigned leds;
13308
13309 if (!pc_at) return; /* PC/XT doesn't have LEDs */
13310
13311 /* encode LED bits */
13312 leds = (slock << 0) | (numlock << 1) | (capslock << 2);
13313
13314 kb_wait(); /* wait for buffer empty */
13315 out_byte(KEYBD, LED_CODE); /* prepare keyboard to accept LED values */
13316 kb_ack(); /* wait for ack response */
13317
13318 kb_wait(); /* wait for buffer empty */
13319 out_byte(KEYBD, leds); /* give keyboard LED values */
13320 kb_ack(); /* wait for ack response */
13321 }
13324 /*==========================================================================*
13325 * kb_wait *
13326 *==========================================================================*/
13327 PRIVATE int kb_wait()
13328 {
13329 /* Wait until the controller is ready; return zero if this times out. */
13330
13331 int retries;
13332
13333 retries = MAX_KB_BUSY_RETRIES + 1;
13334 while (--retries != 0 && in_byte(KB_STATUS) & KB_BUSY)
13335 ; /* wait until not busy */
13336 return(retries); /* nonzero if ready */
13337 }
13340 /*==========================================================================*
13341 * kb_ack *
13342 *==========================================================================*/
13343 PRIVATE int kb_ack()
13344 {
13345 /* Wait until kbd acknowledges last command; return zero if this times out. */
13346
13347 int retries;
13348
13349 retries = MAX_KB_ACK_RETRIES + 1;
13350 while (--retries != 0 && in_byte(KEYBD) != KB_ACK)
13351 ; /* wait for ack */
13352 return(retries); /* nonzero if ack received */
13353 }
13356 /*===========================================================================*
13357 * kb_init *
13358 *===========================================================================*/
13359 PUBLIC void kb_init(tp)
13360 tty_t *tp;
13361 {
13362 /* Initialize the keyboard driver. */
13363
13364 register struct kb_s *kb;
13365
13366 /* Input function. */
13367 tp->tty_devread = kb_read;
13368
13369 kb = kb_addr();
13370
13371 /* Set up input queue. */
13372 kb->ihead = kb->itail = kb->ibuf;
13373
13374 /* Set initial values. */
13375 caps_off = 1;
13376 num_off = 1;
13377 slock_off = 1;
13378 esc = 0;
13379
13380 set_leds(); /* turn off numlock led */
13381
13382 scan_keyboard(); /* stop lockup from leftover keystroke */
13383
13384 put_irq_handler(KEYBOARD_IRQ, kbd_hw_int); /* set the interrupt handler */
13385 enable_irq(KEYBOARD_IRQ); /* safe now everything initialised! */
13386 }
13389 /*===========================================================================*
13390 * kbd_loadmap *
13391 *===========================================================================*/
13392 PUBLIC int kbd_loadmap(user_phys)
13393 phys_bytes user_phys;
13394 {
13395 /* Load a new keymap. */
13396
13397 phys_copy(user_phys, vir2phys(keymap), (phys_bytes) sizeof(keymap));
13398 return(OK);
13399 }
13402 /*===========================================================================*
13403 * func_key *
13404 *===========================================================================*/
13405 PRIVATE int func_key(scode)
13406 int scode; /* scan code for a function key */
13407 {
13408 /* This procedure traps function keys for debugging and control purposes. */
13409
13410 unsigned code;
13411
13412 code = map_key0(scode); /* first ignore modifiers */
13413 if (code < F1 || code > F12) return(FALSE); /* not our job */
13414
13415 switch (map_key(scode)) { /* include modifiers */
13416
13417 case F1: p_dmp(); break; /* print process table */
13418 case F2: map_dmp(); break; /* print memory map */
13419 case F3: toggle_scroll(); break; /* hardware vs. software scrolling */
13420 case CF7: sigchar(&tty_table[CONSOLE], SIGQUIT); break;
13421 case CF8: sigchar(&tty_table[CONSOLE], SIGINT); break;
13422 case CF9: sigchar(&tty_table[CONSOLE], SIGKILL); break;
13423 default: return(FALSE);
13424 }
13425 return(TRUE);
13426 }
13429 /*==========================================================================*
13430 * scan_keyboard *
13431 *==========================================================================*/
13432 PRIVATE int scan_keyboard()
13433 {
13434 /* Fetch the character from the keyboard hardware and acknowledge it. */
13435
13436 int code;
13437 int val;
13438
13439 code = in_byte(KEYBD); /* get the scan code for the key struck */
13440 val = in_byte(PORT_B); /* strobe the keyboard to ack the char */
13441 out_byte(PORT_B, val | KBIT); /* strobe the bit high */
13442 out_byte(PORT_B, val); /* now strobe it low */
13443 return code;
13444 }
13447 /*==========================================================================*
13448 * wreboot *
13449 *==========================================================================*/
13450 PUBLIC void wreboot(how)
13451 int how; /* 0 = halt, 1 = reboot, 2 = panic!, ... */
13452 {
13453 /* Wait for keystrokes for printing debugging info and reboot. */
13454
13455 int quiet, code;
13456 static u16_t magic = MEMCHECK_MAG;
13457 struct tasktab *ttp;
13458
13459 /* Mask all interrupts. */
13460 out_byte(INT_CTLMASK, ~0);
13461
13462 /* Tell several tasks to stop. */
13463 cons_stop();
13464 floppy_stop();
13465 clock_stop();
13466
13467 if (how == RBT_HALT) {
13468 printf("System Haltedn");
13469 if (!mon_return) how = RBT_PANIC;
13470 }
13471
13472 if (how == RBT_PANIC) {
13473 /* A panic! */
13474 printf("Hit ESC to reboot, F-keys for debug dumpsn");
13475
13476 (void) scan_keyboard(); /* ack any old input */
13477 quiet = scan_keyboard();/* quiescent value (0 on PC, last code on AT)*/
13478 for (;;) {
13479 milli_delay(100); /* pause for a decisecond */
13480 code = scan_keyboard();
13481 if (code != quiet) {
13482 /* A key has been pressed. */
13483 if (code == ESC_SCAN) break; /* reboot if ESC typed */
13484 (void) func_key(code); /* process function key */
13485 quiet = scan_keyboard();
13486 }
13487 }
13488 how = RBT_REBOOT;
13489 }
13490
13491 if (how == RBT_REBOOT) printf("Rebootingn");
13492
13493 if (mon_return && how != RBT_RESET) {
13494 /* Reinitialize the interrupt controllers to the BIOS defaults. */
13495 intr_init(0);
13496 out_byte(INT_CTLMASK, 0);
13497 out_byte(INT2_CTLMASK, 0);
13498
13499 /* Return to the boot monitor. */
13500 if (how == RBT_HALT) {
13501 reboot_code = vir2phys("");
13502 } else
13503 if (how == RBT_REBOOT) {
13504 reboot_code = vir2phys("delay;boot");
13505 }
13506 level0(monitor);
13507 }
13508
13509 /* Stop BIOS memory test. */
13510 phys_copy(vir2phys(&magic), (phys_bytes) MEMCHECK_ADR,
13511 (phys_bytes) sizeof(magic));
13512
13513 if (protected_mode) {
13514 /* Use the AT keyboard controller to reset the processor.
13515 * The A20 line is kept enabled in case this code is ever
13516 * run from extended memory, and because some machines
13517 * appear to drive the fake A20 high instead of low just
13518 * after reset, leading to an illegal opode trap. This bug
13519 * is more of a problem if the fake A20 is in use, as it
13520 * would be if the keyboard reset were used for real mode.
13521 */
13522 kb_wait();
13523 out_byte(KB_COMMAND,
13524 KB_PULSE_OUTPUT | (0x0F & ~(KB_GATE_A20 | KB_RESET)));
13525 milli_delay(10);
13526
13527 /* If the nice method fails then do a reset. In protected
13528 * mode this means a processor shutdown.
13529 */
13530 printf("Hard reset...n");
13531 milli_delay(250);
13532 }
13533 /* In real mode, jumping to the reset address is good enough. */
13534 level0(reset);
13535 }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/kernel/console.c
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
13600 /* Code and data for the IBM console driver.
13601 *
13602 * The 6845 video controller used by the IBM PC shares its video memory with
13603 * the CPU somewhere in the 0xB0000 memory bank. To the 6845 this memory
13604 * consists of 16-bit words. Each word has a character code in the low byte
13605 * and a so-called attribute byte in the high byte. The CPU directly modifies
13606 * video memory to display characters, and sets two registers on the 6845 that
13607 * specify the video origin and the cursor position. The video origin is the
13608 * place in video memory where the first character (upper left corner) can
13609 * be found. Moving the origin is a fast way to scroll the screen. Some
13610 * video adapters wrap around the top of video memory, so the origin can
13611 * move without bounds. For other adapters screen memory must sometimes be
13612 * moved to reset the origin. All computations on video memory use character
13613 * (word) addresses for simplicity and assume there is no wrapping. The
13614 * assembly support functions translate the word addresses to byte addresses
13615 * and the scrolling function worries about wrapping.
13616 */
13617
13618 #include "kernel.h"
13619 #include <termios.h>
13620 #include <minix/callnr.h>
13621 #include <minix/com.h>
13622 #include "protect.h"
13623 #include "tty.h"
13624 #include "proc.h"
13625
13626 /* Definitions used by the console driver. */
13627 #define MONO_BASE 0xB0000L /* base of mono video memory */
13628 #define COLOR_BASE 0xB8000L /* base of color video memory */
13629 #define MONO_SIZE 0x1000 /* 4K mono video memory */
13630 #define COLOR_SIZE 0x4000 /* 16K color video memory */
13631 #define EGA_SIZE 0x8000 /* EGA & VGA have at least 32K */
13632 #define BLANK_COLOR 0x0700 /* determines cursor color on blank screen */
13633 #define SCROLL_UP 0 /* scroll forward */
13634 #define SCROLL_DOWN 1 /* scroll backward */
13635 #define BLANK_MEM ((u16_t *) 0) /* tells mem_vid_copy() to blank the screen */
13636 #define CONS_RAM_WORDS 80 /* video ram buffer size */
13637 #define MAX_ESC_PARMS 2 /* number of escape sequence params allowed */
13638
13639 /* Constants relating to the controller chips. */
13640 #define M_6845 0x3B4 /* port for 6845 mono */
13641 #define C_6845 0x3D4 /* port for 6845 color */
13642 #define EGA 0x3C4 /* port for EGA or VGA card */
13643 #define INDEX 0 /* 6845's index register */
13644 #define DATA 1 /* 6845's data register */
13645 #define VID_ORG 12 /* 6845's origin register */
13646 #define CURSOR 14 /* 6845's cursor register */
13647
13648 /* Beeper. */
13649 #define BEEP_FREQ 0x0533 /* value to put into timer to set beep freq */
13650 #define B_TIME 3 /* length of CTRL-G beep is ticks */
13651
13652 /* definitions used for font management */
13653 #define GA_SEQUENCER_INDEX 0x3C4
13654 #define GA_SEQUENCER_DATA 0x3C5
13655 #define GA_GRAPHICS_INDEX 0x3CE
13656 #define GA_GRAPHICS_DATA 0x3CF
13657 #define GA_VIDEO_ADDRESS 0xA0000L
13658 #define GA_FONT_SIZE 8192
13659
13660 /* Global variables used by the console driver. */
13661 PUBLIC unsigned vid_seg; /* video ram selector (0xB0000 or 0xB8000) */
13662 PUBLIC unsigned vid_size; /* 0x2000 for color or 0x0800 for mono */
13663 PUBLIC unsigned vid_mask; /* 0x1FFF for color or 0x07FF for mono */
13664 PUBLIC unsigned blank_color = BLANK_COLOR; /* display code for blank */
13665
13666 /* Private variables used by the console driver. */
13667 PRIVATE int vid_port; /* I/O port for accessing 6845 */
13668 PRIVATE int wrap; /* hardware can wrap? */
13669 PRIVATE int softscroll; /* 1 = software scrolling, 0 = hardware */
13670 PRIVATE unsigned vid_base; /* base of video ram (0xB000 or 0xB800) */
13671 PRIVATE int beeping; /* speaker is beeping? */
13672 #define scr_width 80 /* # characters on a line */
13673 #define scr_lines 25 /* # lines on the screen */
13674 #define scr_size (80*25) /* # characters on the screen */
13675
13676 /* Per console data. */
13677 typedef struct console {
13678 tty_t *c_tty; /* associated TTY struct */
13679 int c_column; /* current column number (0-origin) */
13680 int c_row; /* current row (0 at top of screen) */
13681 int c_rwords; /* number of WORDS (not bytes) in outqueue */
13682 unsigned c_start; /* start of video memory of this console */
13683 unsigned c_limit; /* limit of this console's video memory */
13684 unsigned c_org; /* location in RAM where 6845 base points */
13685 unsigned c_cur; /* current position of cursor in video RAM */
13686 unsigned c_attr; /* character attribute */
13687 unsigned c_blank; /* blank attribute */
13688 char c_esc_state; /* 0=normal, 1=ESC, 2=ESC[ */
13689 char c_esc_intro; /* Distinguishing character following ESC */
13690 int *c_esc_parmp; /* pointer to current escape parameter */
13691 int c_esc_parmv[MAX_ESC_PARMS]; /* list of escape parameters */
13692 u16_t c_ramqueue[CONS_RAM_WORDS]; /* buffer for video RAM */
13693 } console_t;
13694
13695 PRIVATE int nr_cons= 1; /* actual number of consoles */
13696 PRIVATE console_t cons_table[NR_CONS];
13697 PRIVATE console_t *curcons; /* currently visible */
13698
13699 /* Color if using a color controller. */
13700 #define color (vid_port == C_6845)
13701
13702 /* Map from ANSI colors to the attributes used by the PC */
13703 PRIVATE int ansi_colors[8] = {0, 4, 2, 6, 1, 5, 3, 7};
13704
13705 /* Structure used for font management */
13706 struct sequence {
13707 unsigned short index;
13708 unsigned char port;
13709 unsigned char value;
13710 };
13711
13712 FORWARD _PROTOTYPE( void cons_write, (struct tty *tp) );
13713 FORWARD _PROTOTYPE( void cons_echo, (tty_t *tp, int c) );
13714 FORWARD _PROTOTYPE( void out_char, (console_t *cons, int c) );
13715 FORWARD _PROTOTYPE( void beep, (void) );
13716 FORWARD _PROTOTYPE( void do_escape, (console_t *cons, int c) );
13717 FORWARD _PROTOTYPE( void flush, (console_t *cons) );
13718 FORWARD _PROTOTYPE( void parse_escape, (console_t *cons, int c) );
13719 FORWARD _PROTOTYPE( void scroll_screen, (console_t *cons, int dir) );
13720 FORWARD _PROTOTYPE( void set_6845, (int reg, unsigned val) );
13721 FORWARD _PROTOTYPE( void stop_beep, (void) );
13722 FORWARD _PROTOTYPE( void cons_org0, (void) );
13723 FORWARD _PROTOTYPE( void ga_program, (struct sequence *seq) );
13724
13725
13726 /*===========================================================================*
13727 * cons_write *
13728 *===========================================================================*/
13729 PRIVATE void cons_write(tp)
13730 register struct tty *tp; /* tells which terminal is to be used */
13731 {
13732 /* Copy as much data as possible to the output queue, then start I/O. On
13733 * memory-mapped terminals, such as the IBM console, the I/O will also be
13734 * finished, and the counts updated. Keep repeating until all I/O done.
13735 */
13736
13737 int count;
13738 register char *tbuf;
13739 char buf[64];
13740 phys_bytes user_phys;
13741 console_t *cons = tp->tty_priv;
13742
13743 /* Check quickly for nothing to do, so this can be called often without
13744 * unmodular tests elsewhere.
13745 */
13746 if ((count = tp->tty_outleft) == 0 || tp->tty_inhibited) return;
13747
13748 /* Copy the user bytes to buf[] for decent addressing. Loop over the
13749 * copies, since the user buffer may be much larger than buf[].
13750 */
13751 do {
13752 if (count > sizeof(buf)) count = sizeof(buf);
13753 user_phys = proc_vir2phys(proc_addr(tp->tty_outproc), tp->tty_out_vir);
13754 phys_copy(user_phys, vir2phys(buf), (phys_bytes) count);
13755 tbuf = buf;
13756
13757 /* Update terminal data structure. */
13758 tp->tty_out_vir += count;
13759 tp->tty_outcum += count;
13760 tp->tty_outleft -= count;
13761
13762 /* Output each byte of the copy to the screen. Avoid calling
13763 * out_char() for the "easy" characters, put them into the buffer
13764 * directly.
13765 */
13766 do {
13767 if ((unsigned) *tbuf < ' ' || cons->c_esc_state > 0
13768 || cons->c_column >= scr_width
13769 || cons->c_rwords >= buflen(cons->c_ramqueue))
13770 {
13771 out_char(cons, *tbuf++);
13772 } else {
13773 cons->c_ramqueue[cons->c_rwords++] =
13774 cons->c_attr | (*tbuf++ & BYTE);
13775 cons->c_column++;
13776 }
13777 } while (--count != 0);
13778 } while ((count = tp->tty_outleft) != 0 && !tp->tty_inhibited);
13779
13780 flush(cons); /* transfer anything buffered to the screen */
13781
13782 /* Reply to the writer if all output is finished. */
13783 if (tp->tty_outleft == 0) {
13784 tty_reply(tp->tty_outrepcode, tp->tty_outcaller, tp->tty_outproc,
13785 tp->tty_outcum);
13786 tp->tty_outcum = 0;
13787 }
13788 }
13791 /*===========================================================================*
13792 * cons_echo *
13793 *===========================================================================*/
13794 PRIVATE void cons_echo(tp, c)
13795 register tty_t *tp; /* pointer to tty struct */
13796 int c; /* character to be echoed */
13797 {
13798 /* Echo keyboard input (print & flush). */
13799 console_t *cons = tp->tty_priv;
13800
13801 out_char(cons, c);
13802 flush(cons);
13803 }
13806 /*===========================================================================*
13807 * out_char *
13808 *===========================================================================*/
13809 PRIVATE void out_char(cons, c)
13810 register console_t *cons; /* pointer to console struct */
13811 int c; /* character to be output */
13812 {
13813 /* Output a character on the console. Check for escape sequences first. */
13814 if (cons->c_esc_state > 0) {
13815 parse_escape(cons, c);
13816 return;
13817 }
13818
13819 switch(c) {
13820 case 000: /* null is typically used for padding */
13821 return; /* better not do anything */
13822
13823 case 007: /* ring the bell */
13824 flush(cons); /* print any chars queued for output */
13825 beep();
13826 return;
13827
13828 case 'b': /* backspace */
13829 if (--cons->c_column < 0) {
13830 if (--cons->c_row >= 0) cons->c_column += scr_width;
13831 }
13832 flush(cons);
13833 return;
13834
13835 case 'n': /* line feed */
13836 if ((cons->c_tty->tty_termios.c_oflag & (OPOST|ONLCR))
13837 == (OPOST|ONLCR)) {
13838 cons->c_column = 0;
13839 }
13840 /*FALL THROUGH*/
13841 case 013: /* CTRL-K */
13842 case 014: /* CTRL-L */
13843 if (cons->c_row == scr_lines-1) {
13844 scroll_screen(cons, SCROLL_UP);
13845 } else {
13846 cons->c_row++;
13847 }
13848 flush(cons);
13849 return;
13850
13851 case 'r': /* carriage return */
13852 cons->c_column = 0;
13853 flush(cons);
13854 return;
13855
13856 case 't': /* tab */
13857 cons->c_column = (cons->c_column + TAB_SIZE) & ~TAB_MASK;
13858 if (cons->c_column > scr_width) {
13859 cons->c_column -= scr_width;
13860 if (cons->c_row == scr_lines-1) {
13861 scroll_screen(cons, SCROLL_UP);
13862 } else {
13863 cons->c_row++;
13864 }
13865 }
13866 flush(cons);
13867 return;
13868
13869 case 033: /* ESC - start of an escape sequence */
13870 flush(cons); /* print any chars queued for output */
13871 cons->c_esc_state = 1; /* mark ESC as seen */
13872 return;
13873
13874 default: /* printable chars are stored in ramqueue */
13875 if (cons->c_column >= scr_width) {
13876 if (!LINEWRAP) return;
13877 if (cons->c_row == scr_lines-1) {
13878 scroll_screen(cons, SCROLL_UP);
13879 } else {
13880 cons->c_row++;
13881 }
13882 cons->c_column = 0;
13883 flush(cons);
13884 }
13885 if (cons->c_rwords == buflen(cons->c_ramqueue)) flush(cons);
13886 cons->c_ramqueue[cons->c_rwords++] = cons->c_attr | (c & BYTE);
13887 cons->c_column++; /* next column */
13888 return;
13889 }
13890 }
13893 /*===========================================================================*
13894 * scroll_screen *
13895 *===========================================================================*/
13896 PRIVATE void scroll_screen(cons, dir)
13897 register console_t *cons; /* pointer to console struct */
13898 int dir; /* SCROLL_UP or SCROLL_DOWN */
13899 {
13900 unsigned new_line, new_org, chars;
13901
13902 flush(cons);
13903 chars = scr_size - scr_width; /* one screen minus one line */
13904
13905 /* Scrolling the screen is a real nuisance due to the various incompatible
13906 * video cards. This driver supports software scrolling (Hercules?),
13907 * hardware scrolling (mono and CGA cards) and hardware scrolling without
13908 * wrapping (EGA and VGA cards). In the latter case we must make sure that
13909 * c_start <= c_org && c_org + scr_size <= c_limit
13910 * holds, because EGA and VGA don't wrap around the end of video memory.
13911 */
13912 if (dir == SCROLL_UP) {
13913 /* Scroll one line up in 3 ways: soft, avoid wrap, use origin. */
13914 if (softscroll) {
13915 vid_vid_copy(cons->c_start + scr_width, cons->c_start, chars);
13916 } else
13917 if (!wrap && cons->c_org + scr_size + scr_width >= cons->c_limit) {
13918 vid_vid_copy(cons->c_org + scr_width, cons->c_start, chars);