source: mainline/kernel/generic/src/console/kconsole.c@ e98f1c3e

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since e98f1c3e was e98f1c3e, checked in by Martin Decky <martin@…>, 9 years ago

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1/*
2 * Copyright (c) 2005 Jakub Jermar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** @addtogroup genericconsole
30 * @{
31 */
32
33/**
34 * @file kconsole.c
35 * @brief Kernel console.
36 *
37 * This file contains kernel thread managing the kernel console.
38 *
39 */
40
41#include <console/kconsole.h>
42#include <console/console.h>
43#include <console/chardev.h>
44#include <console/cmd.h>
45#include <console/prompt.h>
46#include <print.h>
47#include <panic.h>
48#include <typedefs.h>
49#include <adt/list.h>
50#include <arch.h>
51#include <macros.h>
52#include <debug.h>
53#include <func.h>
54#include <str.h>
55#include <sysinfo/sysinfo.h>
56#include <ddi/device.h>
57#include <symtab.h>
58#include <errno.h>
59#include <putchar.h>
60#include <mm/slab.h>
61
62/** Simple kernel console.
63 *
64 * The console is realized by kernel thread kconsole.
65 * It doesn't understand any useful command on its own,
66 * but makes it possible for other kernel subsystems to
67 * register their own commands.
68 */
69
70/** Locking.
71 *
72 * There is a list of cmd_info_t structures. This list
73 * is protected by cmd_lock spinlock. Note that specially
74 * the link elements of cmd_info_t are protected by
75 * this lock.
76 *
77 * Each cmd_info_t also has its own lock, which protects
78 * all elements thereof except the link element.
79 *
80 * cmd_lock must be acquired before any cmd_info lock.
81 * When locking two cmd info structures, structure with
82 * lower address must be locked first.
83 */
84
85SPINLOCK_INITIALIZE(cmd_lock); /**< Lock protecting command list. */
86LIST_INITIALIZE(cmd_list); /**< Command list. */
87
88static wchar_t history[KCONSOLE_HISTORY][MAX_CMDLINE] = {};
89static size_t history_pos = 0;
90
91/** Initialize kconsole data structures
92 *
93 * This is the most basic initialization, almost no
94 * other kernel subsystem is ready yet.
95 *
96 */
97void kconsole_init(void)
98{
99 unsigned int i;
100
101 cmd_init();
102 for (i = 0; i < KCONSOLE_HISTORY; i++)
103 history[i][0] = 0;
104}
105
106/** Register kconsole command.
107 *
108 * @param cmd Structure describing the command.
109 *
110 * @return False on failure, true on success.
111 *
112 */
113bool cmd_register(cmd_info_t *cmd)
114{
115 spinlock_lock(&cmd_lock);
116
117 /*
118 * Make sure the command is not already listed.
119 */
120 list_foreach(cmd_list, link, cmd_info_t, hlp) {
121 if (hlp == cmd) {
122 /* The command is already there. */
123 spinlock_unlock(&cmd_lock);
124 return false;
125 }
126
127 /* Avoid deadlock. */
128 if (hlp < cmd) {
129 spinlock_lock(&hlp->lock);
130 spinlock_lock(&cmd->lock);
131 } else {
132 spinlock_lock(&cmd->lock);
133 spinlock_lock(&hlp->lock);
134 }
135
136 if (str_cmp(hlp->name, cmd->name) == 0) {
137 /* The command is already there. */
138 spinlock_unlock(&hlp->lock);
139 spinlock_unlock(&cmd->lock);
140 spinlock_unlock(&cmd_lock);
141 return false;
142 }
143
144 spinlock_unlock(&hlp->lock);
145 spinlock_unlock(&cmd->lock);
146 }
147
148 /*
149 * Now the command can be added.
150 */
151 list_append(&cmd->link, &cmd_list);
152
153 spinlock_unlock(&cmd_lock);
154 return true;
155}
156
157/** Print count times a character */
158NO_TRACE static void print_cc(wchar_t ch, size_t count)
159{
160 size_t i;
161 for (i = 0; i < count; i++)
162 putchar(ch);
163}
164
165/** Try to find a command beginning with prefix */
166const char *cmdtab_enum(const char *name, const char **h, void **ctx)
167{
168 link_t **startpos = (link_t**) ctx;
169 size_t namelen = str_length(name);
170
171 spinlock_lock(&cmd_lock);
172
173 if (*startpos == NULL)
174 *startpos = cmd_list.head.next;
175
176 for (; *startpos != &cmd_list.head; *startpos = (*startpos)->next) {
177 cmd_info_t *hlp = list_get_instance(*startpos, cmd_info_t, link);
178
179 const char *curname = hlp->name;
180 if (str_length(curname) < namelen)
181 continue;
182
183 if (str_lcmp(curname, name, namelen) == 0) {
184 *startpos = (*startpos)->next;
185 if (h)
186 *h = hlp->description;
187
188 spinlock_unlock(&cmd_lock);
189 return (curname + str_lsize(curname, namelen));
190 }
191 }
192
193 spinlock_unlock(&cmd_lock);
194 return NULL;
195}
196
197/** Command completion of the commands
198 *
199 * @param name String to match, changed to hint on exit
200 * @param size Input buffer size
201 *
202 * @return Number of found matches
203 *
204 */
205NO_TRACE static int cmdtab_compl(char *input, size_t size, indev_t *indev,
206 hints_enum_func_t hints_enum)
207{
208 const char *name = input;
209
210 size_t found = 0;
211
212 /*
213 * Maximum Match Length: Length of longest matching common
214 * substring in case more than one match is found.
215 */
216 size_t max_match_len = size;
217 size_t max_match_len_tmp = size;
218 void *pos = NULL;
219 const char *hint;
220 const char *help;
221 char *output = malloc(MAX_CMDLINE, 0);
222 size_t hints_to_show = MAX_TAB_HINTS - 1;
223 size_t total_hints_shown = 0;
224 bool continue_showing_hints = true;
225
226 output[0] = 0;
227
228 while ((hint = hints_enum(name, NULL, &pos))) {
229 if ((found == 0) || (str_length(hint) > str_length(output)))
230 str_cpy(output, MAX_CMDLINE, hint);
231
232 found++;
233 }
234
235 /*
236 * If the number of possible completions is more than MAX_TAB_HINTS,
237 * ask the user whether to display them or not.
238 */
239 if (found > MAX_TAB_HINTS) {
240 printf("\n");
241 continue_showing_hints =
242 console_prompt_display_all_hints(indev, found);
243 }
244
245 if ((found > 1) && (str_length(output) != 0)) {
246 printf("\n");
247 pos = NULL;
248 while ((hint = hints_enum(name, &help, &pos))) {
249
250 if (continue_showing_hints) {
251 if (help)
252 printf("%s%s (%s)\n", name, hint, help);
253 else
254 printf("%s%s\n", name, hint);
255
256 --hints_to_show;
257 ++total_hints_shown;
258
259 if ((hints_to_show == 0) && (total_hints_shown != found)) {
260 /* Ask user to continue */
261 continue_showing_hints =
262 console_prompt_more_hints(indev, &hints_to_show);
263 }
264 }
265
266 for (max_match_len_tmp = 0;
267 (output[max_match_len_tmp] ==
268 hint[max_match_len_tmp]) &&
269 (max_match_len_tmp < max_match_len); ++max_match_len_tmp);
270
271 max_match_len = max_match_len_tmp;
272 }
273
274 /* Keep only the characters common in all completions */
275 output[max_match_len] = 0;
276 }
277
278 if (found > 0)
279 str_cpy(input, size, output);
280
281 free(output);
282 return found;
283}
284
285NO_TRACE static cmd_info_t *parse_cmd(const wchar_t *cmdline)
286{
287 size_t start = 0;
288 size_t end;
289 char *tmp;
290
291 while (isspace(cmdline[start]))
292 start++;
293
294 end = start + 1;
295
296 while (!isspace(cmdline[end]))
297 end++;
298
299 tmp = malloc(STR_BOUNDS(end - start + 1), 0);
300
301 wstr_to_str(tmp, end - start + 1, &cmdline[start]);
302
303 spinlock_lock(&cmd_lock);
304
305 list_foreach(cmd_list, link, cmd_info_t, hlp) {
306 spinlock_lock(&hlp->lock);
307
308 if (str_cmp(hlp->name, tmp) == 0) {
309 spinlock_unlock(&hlp->lock);
310 spinlock_unlock(&cmd_lock);
311 free(tmp);
312 return hlp;
313 }
314
315 spinlock_unlock(&hlp->lock);
316 }
317
318 free(tmp);
319 spinlock_unlock(&cmd_lock);
320
321 return NULL;
322}
323
324NO_TRACE static wchar_t *clever_readline(const char *prompt, indev_t *indev)
325{
326 printf("%s> ", prompt);
327
328 size_t position = 0;
329 wchar_t *current = history[history_pos];
330 current[0] = 0;
331 char *tmp = malloc(STR_BOUNDS(MAX_CMDLINE), 0);
332
333 while (true) {
334 wchar_t ch = indev_pop_character(indev);
335
336 if (ch == '\n') {
337 /* Enter */
338 putchar(ch);
339 break;
340 }
341
342 if (ch == '\b') {
343 /* Backspace */
344 if (position == 0)
345 continue;
346
347 if (wstr_remove(current, position - 1)) {
348 position--;
349 putchar('\b');
350 printf("%ls ", current + position);
351 print_cc('\b', wstr_length(current) - position + 1);
352 continue;
353 }
354 }
355
356 if (ch == '\t') {
357 /* Tab completion */
358
359 /* Move to the end of the word */
360 for (; (current[position] != 0) && (!isspace(current[position]));
361 position++)
362 putchar(current[position]);
363
364
365 /*
366 * Find the beginning of the word
367 * and copy it to tmp
368 */
369 size_t beg;
370 unsigned narg = 0;
371 if (position == 0) {
372 tmp[0] = '\0';
373 beg = 0;
374 } else {
375 for (beg = position - 1;
376 (beg > 0) && (!isspace(current[beg]));
377 beg--);
378
379 if (isspace(current[beg]))
380 beg++;
381
382 wstr_to_str(tmp, position - beg + 1, current + beg);
383 }
384
385 /* Count which argument number are we tabbing (narg=0 is cmd) */
386 bool sp = false;
387 for (; beg > 0; beg--) {
388 if (isspace(current[beg])) {
389 if (!sp) {
390 narg++;
391 sp = true;
392 }
393 } else
394 sp = false;
395 }
396
397 if (narg && isspace(current[0]))
398 narg--;
399
400 int found;
401 if (narg == 0) {
402 /* Command completion */
403 found = cmdtab_compl(tmp, STR_BOUNDS(MAX_CMDLINE), indev,
404 cmdtab_enum);
405 } else {
406 /* Arguments completion */
407 cmd_info_t *cmd = parse_cmd(current);
408 if (!cmd || !cmd->hints_enum || cmd->argc < narg)
409 continue;
410 found = cmdtab_compl(tmp, STR_BOUNDS(MAX_CMDLINE), indev,
411 cmd->hints_enum);
412 }
413
414 if (found == 0)
415 continue;
416
417 /*
418 * We have hints, possibly many. In case of more than one hint,
419 * tmp will contain the common prefix.
420 */
421 size_t off = 0;
422 size_t i = 0;
423 while ((ch = str_decode(tmp, &off, STR_NO_LIMIT)) != 0) {
424 if (!wstr_linsert(current, ch, position + i, MAX_CMDLINE))
425 break;
426
427 i++;
428 }
429
430 if (found > 1) {
431 /* No unique hint, list was printed */
432 printf("%s> ", prompt);
433 printf("%ls", current);
434 position += str_length(tmp);
435 print_cc('\b', wstr_length(current) - position);
436 continue;
437 }
438
439 /* We have a hint */
440
441 printf("%ls", current + position);
442 position += str_length(tmp);
443 print_cc('\b', wstr_length(current) - position);
444
445 if (position == wstr_length(current)) {
446 /* Insert a space after the last completed argument */
447 if (wstr_linsert(current, ' ', position, MAX_CMDLINE)) {
448 printf("%ls", current + position);
449 position++;
450 }
451 }
452 continue;
453 }
454
455 if (ch == U_LEFT_ARROW) {
456 /* Left */
457 if (position > 0) {
458 putchar('\b');
459 position--;
460 }
461 continue;
462 }
463
464 if (ch == U_RIGHT_ARROW) {
465 /* Right */
466 if (position < wstr_length(current)) {
467 putchar(current[position]);
468 position++;
469 }
470 continue;
471 }
472
473 if ((ch == U_UP_ARROW) || (ch == U_DOWN_ARROW)) {
474 /* Up, down */
475 print_cc('\b', position);
476 print_cc(' ', wstr_length(current));
477 print_cc('\b', wstr_length(current));
478
479 if (ch == U_UP_ARROW) {
480 /* Up */
481 if (history_pos == 0)
482 history_pos = KCONSOLE_HISTORY - 1;
483 else
484 history_pos--;
485 } else {
486 /* Down */
487 history_pos++;
488 history_pos = history_pos % KCONSOLE_HISTORY;
489 }
490 current = history[history_pos];
491 printf("%ls", current);
492 position = wstr_length(current);
493 continue;
494 }
495
496 if (ch == U_HOME_ARROW) {
497 /* Home */
498 print_cc('\b', position);
499 position = 0;
500 continue;
501 }
502
503 if (ch == U_END_ARROW) {
504 /* End */
505 printf("%ls", current + position);
506 position = wstr_length(current);
507 continue;
508 }
509
510 if (ch == U_DELETE) {
511 /* Delete */
512 if (position == wstr_length(current))
513 continue;
514
515 if (wstr_remove(current, position)) {
516 printf("%ls ", current + position);
517 print_cc('\b', wstr_length(current) - position + 1);
518 }
519 continue;
520 }
521
522 if (wstr_linsert(current, ch, position, MAX_CMDLINE)) {
523 printf("%ls", current + position);
524 position++;
525 print_cc('\b', wstr_length(current) - position);
526 }
527 }
528
529 if (wstr_length(current) > 0) {
530 history_pos++;
531 history_pos = history_pos % KCONSOLE_HISTORY;
532 }
533
534 free(tmp);
535 return current;
536}
537
538bool kconsole_check_poll(void)
539{
540 return check_poll(stdin);
541}
542
543NO_TRACE static bool parse_int_arg(const char *text, size_t len,
544 sysarg_t *result)
545{
546 bool isaddr = false;
547 bool isptr = false;
548
549 /* If we get a name, try to find it in symbol table */
550 if (text[0] == '&') {
551 isaddr = true;
552 text++;
553 len--;
554 } else if (text[0] == '*') {
555 isptr = true;
556 text++;
557 len--;
558 }
559
560 if ((text[0] < '0') || (text[0] > '9')) {
561 char symname[MAX_SYMBOL_NAME];
562 str_ncpy(symname, MAX_SYMBOL_NAME, text, len + 1);
563
564 uintptr_t symaddr;
565 int rc = symtab_addr_lookup(symname, &symaddr);
566 switch (rc) {
567 case ENOENT:
568 printf("Symbol %s not found.\n", symname);
569 return false;
570 case EOVERFLOW:
571 printf("Duplicate symbol %s.\n", symname);
572 symtab_print_search(symname);
573 return false;
574 case ENOTSUP:
575 printf("No symbol information available.\n");
576 return false;
577 case EOK:
578 if (isaddr)
579 *result = (sysarg_t) symaddr;
580 else if (isptr)
581 *result = **((sysarg_t **) symaddr);
582 else
583 *result = *((sysarg_t *) symaddr);
584 break;
585 default:
586 printf("Unknown error.\n");
587 return false;
588 }
589 } else {
590 /* It's a number - convert it */
591 uint64_t value;
592 char *end;
593 int rc = str_uint64_t(text, &end, 0, false, &value);
594 if (end != text + len)
595 rc = EINVAL;
596 switch (rc) {
597 case EINVAL:
598 printf("Invalid number '%s'.\n", text);
599 return false;
600 case EOVERFLOW:
601 printf("Integer overflow in '%s'.\n", text);
602 return false;
603 case EOK:
604 *result = (sysarg_t) value;
605 if (isptr)
606 *result = *((sysarg_t *) *result);
607 break;
608 default:
609 printf("Unknown error parsing '%s'.\n", text);
610 return false;
611 }
612 }
613
614 return true;
615}
616
617/** Parse argument.
618 *
619 * Find start and end positions of command line argument.
620 *
621 * @param cmdline Command line as read from the input device.
622 * @param size Size (in bytes) of the string.
623 * @param start On entry, 'start' contains pointer to the offset
624 * of the first unprocessed character of cmdline.
625 * On successful exit, it marks beginning of the next argument.
626 * @param end Undefined on entry. On exit, 'end' is the offset of the first
627 * character behind the next argument.
628 *
629 * @return False on failure, true on success.
630 *
631 */
632NO_TRACE static bool parse_argument(const char *cmdline, size_t size,
633 size_t *start, size_t *end)
634{
635 ASSERT(start != NULL);
636 ASSERT(end != NULL);
637
638 bool found_start = false;
639 size_t offset = *start;
640 size_t prev = *start;
641 wchar_t ch;
642
643 while ((ch = str_decode(cmdline, &offset, size)) != 0) {
644 if (!found_start) {
645 if (!isspace(ch)) {
646 *start = prev;
647 found_start = true;
648 }
649 } else {
650 if (isspace(ch))
651 break;
652 }
653
654 prev = offset;
655 }
656 *end = prev;
657
658 return found_start;
659}
660
661/** Parse command line.
662 *
663 * @param cmdline Command line as read from input device.
664 * @param size Size (in bytes) of the string.
665 *
666 * @return Structure describing the command.
667 *
668 */
669NO_TRACE static cmd_info_t *parse_cmdline(const char *cmdline, size_t size)
670{
671 size_t start = 0;
672 size_t end = 0;
673 if (!parse_argument(cmdline, size, &start, &end)) {
674 /* Command line did not contain alphanumeric word. */
675 return NULL;
676 }
677 spinlock_lock(&cmd_lock);
678
679 cmd_info_t *cmd = NULL;
680
681 list_foreach(cmd_list, link, cmd_info_t, hlp) {
682 spinlock_lock(&hlp->lock);
683
684 if (str_lcmp(hlp->name, cmdline + start,
685 max(str_length(hlp->name),
686 str_nlength(cmdline + start, (size_t) (end - start)))) == 0) {
687 cmd = hlp;
688 break;
689 }
690
691 spinlock_unlock(&hlp->lock);
692 }
693
694 spinlock_unlock(&cmd_lock);
695
696 if (!cmd) {
697 /* Unknown command. */
698 printf("Unknown command.\n");
699 return NULL;
700 }
701
702 /* cmd == hlp is locked */
703
704 /*
705 * The command line must be further analyzed and
706 * the parameters therefrom must be matched and
707 * converted to those specified in the cmd info
708 * structure.
709 */
710
711 bool error = false;
712 size_t i;
713 for (i = 0; i < cmd->argc; i++) {
714 char *buf;
715
716 start = end;
717 if (!parse_argument(cmdline, size, &start, &end)) {
718 if (cmd->argv[i].type == ARG_TYPE_STRING_OPTIONAL) {
719 buf = (char *) cmd->argv[i].buffer;
720 str_cpy(buf, cmd->argv[i].len, "");
721 continue;
722 }
723
724 printf("Too few arguments.\n");
725 spinlock_unlock(&cmd->lock);
726 return NULL;
727 }
728
729 switch (cmd->argv[i].type) {
730 case ARG_TYPE_STRING:
731 case ARG_TYPE_STRING_OPTIONAL:
732 buf = (char *) cmd->argv[i].buffer;
733 str_ncpy(buf, cmd->argv[i].len, cmdline + start,
734 end - start);
735 break;
736 case ARG_TYPE_INT:
737 if (!parse_int_arg(cmdline + start, end - start,
738 &cmd->argv[i].intval))
739 error = true;
740 break;
741 case ARG_TYPE_VAR:
742 if ((start < end - 1) && (cmdline[start] == '"')) {
743 if (cmdline[end - 1] == '"') {
744 buf = (char *) cmd->argv[i].buffer;
745 str_ncpy(buf, cmd->argv[i].len,
746 cmdline + start + 1,
747 (end - start) - 1);
748 cmd->argv[i].intval = (sysarg_t) buf;
749 cmd->argv[i].vartype = ARG_TYPE_STRING;
750 } else {
751 printf("Wrong syntax.\n");
752 error = true;
753 }
754 } else if (parse_int_arg(cmdline + start,
755 end - start, &cmd->argv[i].intval)) {
756 cmd->argv[i].vartype = ARG_TYPE_INT;
757 } else {
758 printf("Unrecognized variable argument.\n");
759 error = true;
760 }
761 break;
762 case ARG_TYPE_INVALID:
763 default:
764 printf("Invalid argument type\n");
765 error = true;
766 break;
767 }
768 }
769
770 if (error) {
771 spinlock_unlock(&cmd->lock);
772 return NULL;
773 }
774
775 start = end;
776 if (parse_argument(cmdline, size, &start, &end)) {
777 printf("Too many arguments.\n");
778 spinlock_unlock(&cmd->lock);
779 return NULL;
780 }
781
782 spinlock_unlock(&cmd->lock);
783 return cmd;
784}
785
786/** Kernel console prompt.
787 *
788 * @param prompt Kernel console prompt (e.g kconsole/panic).
789 * @param msg Message to display in the beginning.
790 * @param kcon Wait for keypress to show the prompt
791 * and never exit.
792 *
793 */
794void kconsole(const char *prompt, const char *msg, bool kcon)
795{
796 if (!stdin) {
797 LOG("No stdin for kernel console");
798 return;
799 }
800
801 if (msg)
802 printf("%s", msg);
803
804 if (kcon)
805 indev_pop_character(stdin);
806 else
807 printf("Type \"exit\" to leave the console.\n");
808
809 char *cmdline = malloc(STR_BOUNDS(MAX_CMDLINE), 0);
810 while (true) {
811 wchar_t *tmp = clever_readline((char *) prompt, stdin);
812 size_t len = wstr_length(tmp);
813 if (!len)
814 continue;
815
816 wstr_to_str(cmdline, STR_BOUNDS(MAX_CMDLINE), tmp);
817
818 if ((!kcon) && (len == 4) && (str_lcmp(cmdline, "exit", 4) == 0))
819 break;
820
821 cmd_info_t *cmd_info = parse_cmdline(cmdline, STR_BOUNDS(MAX_CMDLINE));
822 if (!cmd_info)
823 continue;
824
825 (void) cmd_info->func(cmd_info->argv);
826 }
827 free(cmdline);
828}
829
830/** Kernel console managing thread.
831 *
832 */
833void kconsole_thread(void *data)
834{
835 kconsole("kconsole", "Kernel console ready (press any key to activate)\n", true);
836}
837
838/** @}
839 */
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