source: mainline/kernel/generic/src/console/kconsole.c@ 63e27ef

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 63e27ef was 63e27ef, checked in by Jiri Svoboda <jiri@…>, 8 years ago

ASSERT → assert
  • Property mode set to 100644
File size: 18.9 KB
Line 
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 <assert.h>
42#include <console/kconsole.h>
43#include <console/console.h>
44#include <console/chardev.h>
45#include <console/cmd.h>
46#include <console/prompt.h>
47#include <print.h>
48#include <panic.h>
49#include <typedefs.h>
50#include <adt/list.h>
51#include <arch.h>
52#include <macros.h>
53#include <debug.h>
54#include <func.h>
55#include <str.h>
56#include <sysinfo/sysinfo.h>
57#include <ddi/device.h>
58#include <symtab.h>
59#include <errno.h>
60#include <putchar.h>
61#include <mm/slab.h>
62
63/** Simple kernel console.
64 *
65 * The console is realized by kernel thread kconsole.
66 * It doesn't understand any useful command on its own,
67 * but makes it possible for other kernel subsystems to
68 * register their own commands.
69 */
70
71/** Locking.
72 *
73 * There is a list of cmd_info_t structures. This list
74 * is protected by cmd_lock spinlock. Note that specially
75 * the link elements of cmd_info_t are protected by
76 * this lock.
77 *
78 * Each cmd_info_t also has its own lock, which protects
79 * all elements thereof except the link element.
80 *
81 * cmd_lock must be acquired before any cmd_info lock.
82 * When locking two cmd info structures, structure with
83 * lower address must be locked first.
84 */
85
86SPINLOCK_INITIALIZE(cmd_lock); /**< Lock protecting command list. */
87LIST_INITIALIZE(cmd_list); /**< Command list. */
88
89static wchar_t history[KCONSOLE_HISTORY][MAX_CMDLINE] = {};
90static size_t history_pos = 0;
91
92/** Initialize kconsole data structures
93 *
94 * This is the most basic initialization, almost no
95 * other kernel subsystem is ready yet.
96 *
97 */
98void kconsole_init(void)
99{
100 unsigned int i;
101
102 cmd_init();
103 for (i = 0; i < KCONSOLE_HISTORY; i++)
104 history[i][0] = 0;
105}
106
107/** Register kconsole command.
108 *
109 * @param cmd Structure describing the command.
110 *
111 * @return False on failure, true on success.
112 *
113 */
114bool cmd_register(cmd_info_t *cmd)
115{
116 spinlock_lock(&cmd_lock);
117
118 /*
119 * Make sure the command is not already listed.
120 */
121 list_foreach(cmd_list, link, cmd_info_t, hlp) {
122 if (hlp == cmd) {
123 /* The command is already there. */
124 spinlock_unlock(&cmd_lock);
125 return false;
126 }
127
128 /* Avoid deadlock. */
129 if (hlp < cmd) {
130 spinlock_lock(&hlp->lock);
131 spinlock_lock(&cmd->lock);
132 } else {
133 spinlock_lock(&cmd->lock);
134 spinlock_lock(&hlp->lock);
135 }
136
137 if (str_cmp(hlp->name, cmd->name) == 0) {
138 /* The command is already there. */
139 spinlock_unlock(&hlp->lock);
140 spinlock_unlock(&cmd->lock);
141 spinlock_unlock(&cmd_lock);
142 return false;
143 }
144
145 spinlock_unlock(&hlp->lock);
146 spinlock_unlock(&cmd->lock);
147 }
148
149 /*
150 * Now the command can be added.
151 */
152 list_append(&cmd->link, &cmd_list);
153
154 spinlock_unlock(&cmd_lock);
155 return true;
156}
157
158/** Print count times a character */
159NO_TRACE static void print_cc(wchar_t ch, size_t count)
160{
161 size_t i;
162 for (i = 0; i < count; i++)
163 putchar(ch);
164}
165
166/** Try to find a command beginning with prefix */
167const char *cmdtab_enum(const char *name, const char **h, void **ctx)
168{
169 link_t **startpos = (link_t**) ctx;
170 size_t namelen = str_length(name);
171
172 spinlock_lock(&cmd_lock);
173
174 if (*startpos == NULL)
175 *startpos = cmd_list.head.next;
176
177 for (; *startpos != &cmd_list.head; *startpos = (*startpos)->next) {
178 cmd_info_t *hlp = list_get_instance(*startpos, cmd_info_t, link);
179
180 const char *curname = hlp->name;
181 if (str_length(curname) < namelen)
182 continue;
183
184 if (str_lcmp(curname, name, namelen) == 0) {
185 *startpos = (*startpos)->next;
186 if (h)
187 *h = hlp->description;
188
189 spinlock_unlock(&cmd_lock);
190 return (curname + str_lsize(curname, namelen));
191 }
192 }
193
194 spinlock_unlock(&cmd_lock);
195 return NULL;
196}
197
198/** Command completion of the commands
199 *
200 * @param name String to match, changed to hint on exit
201 * @param size Input buffer size
202 *
203 * @return Number of found matches
204 *
205 */
206NO_TRACE static int cmdtab_compl(char *input, size_t size, indev_t *indev,
207 hints_enum_func_t hints_enum)
208{
209 const char *name = input;
210
211 size_t found = 0;
212
213 /*
214 * Maximum Match Length: Length of longest matching common
215 * substring in case more than one match is found.
216 */
217 size_t max_match_len = size;
218 size_t max_match_len_tmp = size;
219 void *pos = NULL;
220 const char *hint;
221 const char *help;
222 char *output = malloc(MAX_CMDLINE, 0);
223 size_t hints_to_show = MAX_TAB_HINTS - 1;
224 size_t total_hints_shown = 0;
225 bool continue_showing_hints = true;
226
227 output[0] = 0;
228
229 while ((hint = hints_enum(name, NULL, &pos))) {
230 if ((found == 0) || (str_length(hint) > str_length(output)))
231 str_cpy(output, MAX_CMDLINE, hint);
232
233 found++;
234 }
235
236 /*
237 * If the number of possible completions is more than MAX_TAB_HINTS,
238 * ask the user whether to display them or not.
239 */
240 if (found > MAX_TAB_HINTS) {
241 printf("\n");
242 continue_showing_hints =
243 console_prompt_display_all_hints(indev, found);
244 }
245
246 if ((found > 1) && (str_length(output) != 0)) {
247 printf("\n");
248 pos = NULL;
249 while ((hint = hints_enum(name, &help, &pos))) {
250
251 if (continue_showing_hints) {
252 if (help)
253 printf("%s%s (%s)\n", name, hint, help);
254 else
255 printf("%s%s\n", name, hint);
256
257 --hints_to_show;
258 ++total_hints_shown;
259
260 if ((hints_to_show == 0) && (total_hints_shown != found)) {
261 /* Ask user to continue */
262 continue_showing_hints =
263 console_prompt_more_hints(indev, &hints_to_show);
264 }
265 }
266
267 for (max_match_len_tmp = 0;
268 (output[max_match_len_tmp] ==
269 hint[max_match_len_tmp]) &&
270 (max_match_len_tmp < max_match_len); ++max_match_len_tmp);
271
272 max_match_len = max_match_len_tmp;
273 }
274
275 /* Keep only the characters common in all completions */
276 output[max_match_len] = 0;
277 }
278
279 if (found > 0)
280 str_cpy(input, size, output);
281
282 free(output);
283 return found;
284}
285
286NO_TRACE static cmd_info_t *parse_cmd(const wchar_t *cmdline)
287{
288 size_t start = 0;
289 size_t end;
290 char *tmp;
291
292 while (isspace(cmdline[start]))
293 start++;
294
295 end = start + 1;
296
297 while (!isspace(cmdline[end]))
298 end++;
299
300 tmp = malloc(STR_BOUNDS(end - start + 1), 0);
301
302 wstr_to_str(tmp, end - start + 1, &cmdline[start]);
303
304 spinlock_lock(&cmd_lock);
305
306 list_foreach(cmd_list, link, cmd_info_t, hlp) {
307 spinlock_lock(&hlp->lock);
308
309 if (str_cmp(hlp->name, tmp) == 0) {
310 spinlock_unlock(&hlp->lock);
311 spinlock_unlock(&cmd_lock);
312 free(tmp);
313 return hlp;
314 }
315
316 spinlock_unlock(&hlp->lock);
317 }
318
319 free(tmp);
320 spinlock_unlock(&cmd_lock);
321
322 return NULL;
323}
324
325NO_TRACE static wchar_t *clever_readline(const char *prompt, indev_t *indev)
326{
327 printf("%s> ", prompt);
328
329 size_t position = 0;
330 wchar_t *current = history[history_pos];
331 current[0] = 0;
332 char *tmp = malloc(STR_BOUNDS(MAX_CMDLINE), 0);
333
334 while (true) {
335 wchar_t ch = indev_pop_character(indev);
336
337 if (ch == '\n') {
338 /* Enter */
339 putchar(ch);
340 break;
341 }
342
343 if (ch == '\b') {
344 /* Backspace */
345 if (position == 0)
346 continue;
347
348 if (wstr_remove(current, position - 1)) {
349 position--;
350 putchar('\b');
351 printf("%ls ", current + position);
352 print_cc('\b', wstr_length(current) - position + 1);
353 continue;
354 }
355 }
356
357 if (ch == '\t') {
358 /* Tab completion */
359
360 /* Move to the end of the word */
361 for (; (current[position] != 0) && (!isspace(current[position]));
362 position++)
363 putchar(current[position]);
364
365
366 /*
367 * Find the beginning of the word
368 * and copy it to tmp
369 */
370 size_t beg;
371 unsigned narg = 0;
372 if (position == 0) {
373 tmp[0] = '\0';
374 beg = 0;
375 } else {
376 for (beg = position - 1;
377 (beg > 0) && (!isspace(current[beg]));
378 beg--);
379
380 if (isspace(current[beg]))
381 beg++;
382
383 wstr_to_str(tmp, position - beg + 1, current + beg);
384 }
385
386 /* Count which argument number are we tabbing (narg=0 is cmd) */
387 bool sp = false;
388 for (; beg > 0; beg--) {
389 if (isspace(current[beg])) {
390 if (!sp) {
391 narg++;
392 sp = true;
393 }
394 } else
395 sp = false;
396 }
397
398 if (narg && isspace(current[0]))
399 narg--;
400
401 int found;
402 if (narg == 0) {
403 /* Command completion */
404 found = cmdtab_compl(tmp, STR_BOUNDS(MAX_CMDLINE), indev,
405 cmdtab_enum);
406 } else {
407 /* Arguments completion */
408 cmd_info_t *cmd = parse_cmd(current);
409 if (!cmd || !cmd->hints_enum || cmd->argc < narg)
410 continue;
411 found = cmdtab_compl(tmp, STR_BOUNDS(MAX_CMDLINE), indev,
412 cmd->hints_enum);
413 }
414
415 if (found == 0)
416 continue;
417
418 /*
419 * We have hints, possibly many. In case of more than one hint,
420 * tmp will contain the common prefix.
421 */
422 size_t off = 0;
423 size_t i = 0;
424 while ((ch = str_decode(tmp, &off, STR_NO_LIMIT)) != 0) {
425 if (!wstr_linsert(current, ch, position + i, MAX_CMDLINE))
426 break;
427
428 i++;
429 }
430
431 if (found > 1) {
432 /* No unique hint, list was printed */
433 printf("%s> ", prompt);
434 printf("%ls", current);
435 position += str_length(tmp);
436 print_cc('\b', wstr_length(current) - position);
437 continue;
438 }
439
440 /* We have a hint */
441
442 printf("%ls", current + position);
443 position += str_length(tmp);
444 print_cc('\b', wstr_length(current) - position);
445
446 if (position == wstr_length(current)) {
447 /* Insert a space after the last completed argument */
448 if (wstr_linsert(current, ' ', position, MAX_CMDLINE)) {
449 printf("%ls", current + position);
450 position++;
451 }
452 }
453 continue;
454 }
455
456 if (ch == U_LEFT_ARROW) {
457 /* Left */
458 if (position > 0) {
459 putchar('\b');
460 position--;
461 }
462 continue;
463 }
464
465 if (ch == U_RIGHT_ARROW) {
466 /* Right */
467 if (position < wstr_length(current)) {
468 putchar(current[position]);
469 position++;
470 }
471 continue;
472 }
473
474 if ((ch == U_UP_ARROW) || (ch == U_DOWN_ARROW)) {
475 /* Up, down */
476 print_cc('\b', position);
477 print_cc(' ', wstr_length(current));
478 print_cc('\b', wstr_length(current));
479
480 if (ch == U_UP_ARROW) {
481 /* Up */
482 if (history_pos == 0)
483 history_pos = KCONSOLE_HISTORY - 1;
484 else
485 history_pos--;
486 } else {
487 /* Down */
488 history_pos++;
489 history_pos = history_pos % KCONSOLE_HISTORY;
490 }
491 current = history[history_pos];
492 printf("%ls", current);
493 position = wstr_length(current);
494 continue;
495 }
496
497 if (ch == U_HOME_ARROW) {
498 /* Home */
499 print_cc('\b', position);
500 position = 0;
501 continue;
502 }
503
504 if (ch == U_END_ARROW) {
505 /* End */
506 printf("%ls", current + position);
507 position = wstr_length(current);
508 continue;
509 }
510
511 if (ch == U_DELETE) {
512 /* Delete */
513 if (position == wstr_length(current))
514 continue;
515
516 if (wstr_remove(current, position)) {
517 printf("%ls ", current + position);
518 print_cc('\b', wstr_length(current) - position + 1);
519 }
520 continue;
521 }
522
523 if (wstr_linsert(current, ch, position, MAX_CMDLINE)) {
524 printf("%ls", current + position);
525 position++;
526 print_cc('\b', wstr_length(current) - position);
527 }
528 }
529
530 if (wstr_length(current) > 0) {
531 history_pos++;
532 history_pos = history_pos % KCONSOLE_HISTORY;
533 }
534
535 free(tmp);
536 return current;
537}
538
539bool kconsole_check_poll(void)
540{
541 return check_poll(stdin);
542}
543
544NO_TRACE static bool parse_int_arg(const char *text, size_t len,
545 sysarg_t *result)
546{
547 bool isaddr = false;
548 bool isptr = false;
549
550 /* If we get a name, try to find it in symbol table */
551 if (text[0] == '&') {
552 isaddr = true;
553 text++;
554 len--;
555 } else if (text[0] == '*') {
556 isptr = true;
557 text++;
558 len--;
559 }
560
561 if ((text[0] < '0') || (text[0] > '9')) {
562 char symname[MAX_SYMBOL_NAME];
563 str_ncpy(symname, MAX_SYMBOL_NAME, text, len + 1);
564
565 uintptr_t symaddr;
566 int rc = symtab_addr_lookup(symname, &symaddr);
567 switch (rc) {
568 case ENOENT:
569 printf("Symbol %s not found.\n", symname);
570 return false;
571 case EOVERFLOW:
572 printf("Duplicate symbol %s.\n", symname);
573 symtab_print_search(symname);
574 return false;
575 case ENOTSUP:
576 printf("No symbol information available.\n");
577 return false;
578 case EOK:
579 if (isaddr)
580 *result = (sysarg_t) symaddr;
581 else if (isptr)
582 *result = **((sysarg_t **) symaddr);
583 else
584 *result = *((sysarg_t *) symaddr);
585 break;
586 default:
587 printf("Unknown error.\n");
588 return false;
589 }
590 } else {
591 /* It's a number - convert it */
592 uint64_t value;
593 char *end;
594 int rc = str_uint64_t(text, &end, 0, false, &value);
595 if (end != text + len)
596 rc = EINVAL;
597 switch (rc) {
598 case EINVAL:
599 printf("Invalid number '%s'.\n", text);
600 return false;
601 case EOVERFLOW:
602 printf("Integer overflow in '%s'.\n", text);
603 return false;
604 case EOK:
605 *result = (sysarg_t) value;
606 if (isptr)
607 *result = *((sysarg_t *) *result);
608 break;
609 default:
610 printf("Unknown error parsing '%s'.\n", text);
611 return false;
612 }
613 }
614
615 return true;
616}
617
618/** Parse argument.
619 *
620 * Find start and end positions of command line argument.
621 *
622 * @param cmdline Command line as read from the input device.
623 * @param size Size (in bytes) of the string.
624 * @param start On entry, 'start' contains pointer to the offset
625 * of the first unprocessed character of cmdline.
626 * On successful exit, it marks beginning of the next argument.
627 * @param end Undefined on entry. On exit, 'end' is the offset of the first
628 * character behind the next argument.
629 *
630 * @return False on failure, true on success.
631 *
632 */
633NO_TRACE static bool parse_argument(const char *cmdline, size_t size,
634 size_t *start, size_t *end)
635{
636 assert(start != NULL);
637 assert(end != NULL);
638
639 bool found_start = false;
640 size_t offset = *start;
641 size_t prev = *start;
642 wchar_t ch;
643
644 while ((ch = str_decode(cmdline, &offset, size)) != 0) {
645 if (!found_start) {
646 if (!isspace(ch)) {
647 *start = prev;
648 found_start = true;
649 }
650 } else {
651 if (isspace(ch))
652 break;
653 }
654
655 prev = offset;
656 }
657 *end = prev;
658
659 return found_start;
660}
661
662/** Parse command line.
663 *
664 * @param cmdline Command line as read from input device.
665 * @param size Size (in bytes) of the string.
666 *
667 * @return Structure describing the command.
668 *
669 */
670NO_TRACE static cmd_info_t *parse_cmdline(const char *cmdline, size_t size)
671{
672 size_t start = 0;
673 size_t end = 0;
674 if (!parse_argument(cmdline, size, &start, &end)) {
675 /* Command line did not contain alphanumeric word. */
676 return NULL;
677 }
678 spinlock_lock(&cmd_lock);
679
680 cmd_info_t *cmd = NULL;
681
682 list_foreach(cmd_list, link, cmd_info_t, hlp) {
683 spinlock_lock(&hlp->lock);
684
685 if (str_lcmp(hlp->name, cmdline + start,
686 max(str_length(hlp->name),
687 str_nlength(cmdline + start, (size_t) (end - start)))) == 0) {
688 cmd = hlp;
689 break;
690 }
691
692 spinlock_unlock(&hlp->lock);
693 }
694
695 spinlock_unlock(&cmd_lock);
696
697 if (!cmd) {
698 /* Unknown command. */
699 printf("Unknown command.\n");
700 return NULL;
701 }
702
703 /* cmd == hlp is locked */
704
705 /*
706 * The command line must be further analyzed and
707 * the parameters therefrom must be matched and
708 * converted to those specified in the cmd info
709 * structure.
710 */
711
712 bool error = false;
713 size_t i;
714 for (i = 0; i < cmd->argc; i++) {
715 char *buf;
716
717 start = end;
718 if (!parse_argument(cmdline, size, &start, &end)) {
719 if (cmd->argv[i].type == ARG_TYPE_STRING_OPTIONAL) {
720 buf = (char *) cmd->argv[i].buffer;
721 str_cpy(buf, cmd->argv[i].len, "");
722 continue;
723 }
724
725 printf("Too few arguments.\n");
726 spinlock_unlock(&cmd->lock);
727 return NULL;
728 }
729
730 switch (cmd->argv[i].type) {
731 case ARG_TYPE_STRING:
732 case ARG_TYPE_STRING_OPTIONAL:
733 buf = (char *) cmd->argv[i].buffer;
734 str_ncpy(buf, cmd->argv[i].len, cmdline + start,
735 end - start);
736 break;
737 case ARG_TYPE_INT:
738 if (!parse_int_arg(cmdline + start, end - start,
739 &cmd->argv[i].intval))
740 error = true;
741 break;
742 case ARG_TYPE_VAR:
743 if ((start < end - 1) && (cmdline[start] == '"')) {
744 if (cmdline[end - 1] == '"') {
745 buf = (char *) cmd->argv[i].buffer;
746 str_ncpy(buf, cmd->argv[i].len,
747 cmdline + start + 1,
748 (end - start) - 1);
749 cmd->argv[i].intval = (sysarg_t) buf;
750 cmd->argv[i].vartype = ARG_TYPE_STRING;
751 } else {
752 printf("Wrong syntax.\n");
753 error = true;
754 }
755 } else if (parse_int_arg(cmdline + start,
756 end - start, &cmd->argv[i].intval)) {
757 cmd->argv[i].vartype = ARG_TYPE_INT;
758 } else {
759 printf("Unrecognized variable argument.\n");
760 error = true;
761 }
762 break;
763 case ARG_TYPE_INVALID:
764 default:
765 printf("Invalid argument type\n");
766 error = true;
767 break;
768 }
769 }
770
771 if (error) {
772 spinlock_unlock(&cmd->lock);
773 return NULL;
774 }
775
776 start = end;
777 if (parse_argument(cmdline, size, &start, &end)) {
778 printf("Too many arguments.\n");
779 spinlock_unlock(&cmd->lock);
780 return NULL;
781 }
782
783 spinlock_unlock(&cmd->lock);
784 return cmd;
785}
786
787/** Kernel console prompt.
788 *
789 * @param prompt Kernel console prompt (e.g kconsole/panic).
790 * @param msg Message to display in the beginning.
791 * @param kcon Wait for keypress to show the prompt
792 * and never exit.
793 *
794 */
795void kconsole(const char *prompt, const char *msg, bool kcon)
796{
797 if (!stdin) {
798 LOG("No stdin for kernel console");
799 return;
800 }
801
802 if (msg)
803 printf("%s", msg);
804
805 if (kcon)
806 indev_pop_character(stdin);
807 else
808 printf("Type \"exit\" to leave the console.\n");
809
810 char *cmdline = malloc(STR_BOUNDS(MAX_CMDLINE), 0);
811 while (true) {
812 wchar_t *tmp = clever_readline((char *) prompt, stdin);
813 size_t len = wstr_length(tmp);
814 if (!len)
815 continue;
816
817 wstr_to_str(cmdline, STR_BOUNDS(MAX_CMDLINE), tmp);
818
819 if ((!kcon) && (len == 4) && (str_lcmp(cmdline, "exit", 4) == 0))
820 break;
821
822 cmd_info_t *cmd_info = parse_cmdline(cmdline, STR_BOUNDS(MAX_CMDLINE));
823 if (!cmd_info)
824 continue;
825
826 (void) cmd_info->func(cmd_info->argv);
827 }
828 free(cmdline);
829}
830
831/** Kernel console managing thread.
832 *
833 */
834void kconsole_thread(void *data)
835{
836 kconsole("kconsole", "Kernel console ready (press any key to activate)\n", true);
837}
838
839/** @}
840 */
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