• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
3  *
4  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation;
8  * version 2.1 of the License (not later!)
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with this program; if not,  see <http://www.gnu.org/licenses>
17  *
18  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
19  */
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <stdarg.h>
24 #include <errno.h>
25 #include <sys/types.h>
26 
27 #include "event-parse.h"
28 #include "event-utils.h"
29 
30 #define COMM "COMM"
31 
32 static struct format_field comm = {
33 	.name = "COMM",
34 };
35 
36 struct event_list {
37 	struct event_list	*next;
38 	struct event_format	*event;
39 };
40 
41 #define MAX_ERR_STR_SIZE 256
42 
show_error(char ** error_str,const char * fmt,...)43 static void show_error(char **error_str, const char *fmt, ...)
44 {
45 	unsigned long long index;
46 	const char *input;
47 	char *error;
48 	va_list ap;
49 	int len;
50 	int i;
51 
52 	if (!error_str)
53 		return;
54 
55 	input = pevent_get_input_buf();
56 	index = pevent_get_input_buf_ptr();
57 	len = input ? strlen(input) : 0;
58 
59 	error = malloc_or_die(MAX_ERR_STR_SIZE + (len*2) + 3);
60 
61 	if (len) {
62 		strcpy(error, input);
63 		error[len] = '\n';
64 		for (i = 1; i < len && i < index; i++)
65 			error[len+i] = ' ';
66 		error[len + i] = '^';
67 		error[len + i + 1] = '\n';
68 		len += i+2;
69 	}
70 
71 	va_start(ap, fmt);
72 	vsnprintf(error + len, MAX_ERR_STR_SIZE, fmt, ap);
73 	va_end(ap);
74 
75 	*error_str = error;
76 }
77 
free_token(char * token)78 static void free_token(char *token)
79 {
80 	pevent_free_token(token);
81 }
82 
read_token(char ** tok)83 static enum event_type read_token(char **tok)
84 {
85 	enum event_type type;
86 	char *token = NULL;
87 
88 	do {
89 		free_token(token);
90 		type = pevent_read_token(&token);
91 	} while (type == EVENT_NEWLINE || type == EVENT_SPACE);
92 
93 	/* If token is = or ! check to see if the next char is ~ */
94 	if (token &&
95 	    (strcmp(token, "=") == 0 || strcmp(token, "!") == 0) &&
96 	    pevent_peek_char() == '~') {
97 		/* append it */
98 		*tok = malloc_or_die(3);
99 		sprintf(*tok, "%c%c", *token, '~');
100 		free_token(token);
101 		/* Now remove the '~' from the buffer */
102 		pevent_read_token(&token);
103 		free_token(token);
104 	} else
105 		*tok = token;
106 
107 	return type;
108 }
109 
filter_cmp(const void * a,const void * b)110 static int filter_cmp(const void *a, const void *b)
111 {
112 	const struct filter_type *ea = a;
113 	const struct filter_type *eb = b;
114 
115 	if (ea->event_id < eb->event_id)
116 		return -1;
117 
118 	if (ea->event_id > eb->event_id)
119 		return 1;
120 
121 	return 0;
122 }
123 
124 static struct filter_type *
find_filter_type(struct event_filter * filter,int id)125 find_filter_type(struct event_filter *filter, int id)
126 {
127 	struct filter_type *filter_type;
128 	struct filter_type key;
129 
130 	key.event_id = id;
131 
132 	filter_type = bsearch(&key, filter->event_filters,
133 			      filter->filters,
134 			      sizeof(*filter->event_filters),
135 			      filter_cmp);
136 
137 	return filter_type;
138 }
139 
140 static struct filter_type *
add_filter_type(struct event_filter * filter,int id)141 add_filter_type(struct event_filter *filter, int id)
142 {
143 	struct filter_type *filter_type;
144 	int i;
145 
146 	filter_type = find_filter_type(filter, id);
147 	if (filter_type)
148 		return filter_type;
149 
150 	filter->event_filters =	realloc(filter->event_filters,
151 					sizeof(*filter->event_filters) *
152 					(filter->filters + 1));
153 	if (!filter->event_filters)
154 		die("Could not allocate filter");
155 
156 	for (i = 0; i < filter->filters; i++) {
157 		if (filter->event_filters[i].event_id > id)
158 			break;
159 	}
160 
161 	if (i < filter->filters)
162 		memmove(&filter->event_filters[i+1],
163 			&filter->event_filters[i],
164 			sizeof(*filter->event_filters) *
165 			(filter->filters - i));
166 
167 	filter_type = &filter->event_filters[i];
168 	filter_type->event_id = id;
169 	filter_type->event = pevent_find_event(filter->pevent, id);
170 	filter_type->filter = NULL;
171 
172 	filter->filters++;
173 
174 	return filter_type;
175 }
176 
177 /**
178  * pevent_filter_alloc - create a new event filter
179  * @pevent: The pevent that this filter is associated with
180  */
pevent_filter_alloc(struct pevent * pevent)181 struct event_filter *pevent_filter_alloc(struct pevent *pevent)
182 {
183 	struct event_filter *filter;
184 
185 	filter = malloc_or_die(sizeof(*filter));
186 	memset(filter, 0, sizeof(*filter));
187 	filter->pevent = pevent;
188 	pevent_ref(pevent);
189 
190 	return filter;
191 }
192 
allocate_arg(void)193 static struct filter_arg *allocate_arg(void)
194 {
195 	struct filter_arg *arg;
196 
197 	arg = malloc_or_die(sizeof(*arg));
198 	memset(arg, 0, sizeof(*arg));
199 
200 	return arg;
201 }
202 
free_arg(struct filter_arg * arg)203 static void free_arg(struct filter_arg *arg)
204 {
205 	if (!arg)
206 		return;
207 
208 	switch (arg->type) {
209 	case FILTER_ARG_NONE:
210 	case FILTER_ARG_BOOLEAN:
211 		break;
212 
213 	case FILTER_ARG_NUM:
214 		free_arg(arg->num.left);
215 		free_arg(arg->num.right);
216 		break;
217 
218 	case FILTER_ARG_EXP:
219 		free_arg(arg->exp.left);
220 		free_arg(arg->exp.right);
221 		break;
222 
223 	case FILTER_ARG_STR:
224 		free(arg->str.val);
225 		regfree(&arg->str.reg);
226 		free(arg->str.buffer);
227 		break;
228 
229 	case FILTER_ARG_VALUE:
230 		if (arg->value.type == FILTER_STRING ||
231 		    arg->value.type == FILTER_CHAR)
232 			free(arg->value.str);
233 		break;
234 
235 	case FILTER_ARG_OP:
236 		free_arg(arg->op.left);
237 		free_arg(arg->op.right);
238 	default:
239 		break;
240 	}
241 
242 	free(arg);
243 }
244 
add_event(struct event_list ** events,struct event_format * event)245 static void add_event(struct event_list **events,
246 		      struct event_format *event)
247 {
248 	struct event_list *list;
249 
250 	list = malloc_or_die(sizeof(*list));
251 	list->next = *events;
252 	*events = list;
253 	list->event = event;
254 }
255 
event_match(struct event_format * event,regex_t * sreg,regex_t * ereg)256 static int event_match(struct event_format *event,
257 		       regex_t *sreg, regex_t *ereg)
258 {
259 	if (sreg) {
260 		return !regexec(sreg, event->system, 0, NULL, 0) &&
261 			!regexec(ereg, event->name, 0, NULL, 0);
262 	}
263 
264 	return !regexec(ereg, event->system, 0, NULL, 0) ||
265 		!regexec(ereg, event->name, 0, NULL, 0);
266 }
267 
268 static int
find_event(struct pevent * pevent,struct event_list ** events,char * sys_name,char * event_name)269 find_event(struct pevent *pevent, struct event_list **events,
270 	   char *sys_name, char *event_name)
271 {
272 	struct event_format *event;
273 	regex_t ereg;
274 	regex_t sreg;
275 	int match = 0;
276 	char *reg;
277 	int ret;
278 	int i;
279 
280 	if (!event_name) {
281 		/* if no name is given, then swap sys and name */
282 		event_name = sys_name;
283 		sys_name = NULL;
284 	}
285 
286 	reg = malloc_or_die(strlen(event_name) + 3);
287 	sprintf(reg, "^%s$", event_name);
288 
289 	ret = regcomp(&ereg, reg, REG_ICASE|REG_NOSUB);
290 	free(reg);
291 
292 	if (ret)
293 		return -1;
294 
295 	if (sys_name) {
296 		reg = malloc_or_die(strlen(sys_name) + 3);
297 		sprintf(reg, "^%s$", sys_name);
298 		ret = regcomp(&sreg, reg, REG_ICASE|REG_NOSUB);
299 		free(reg);
300 		if (ret) {
301 			regfree(&ereg);
302 			return -1;
303 		}
304 	}
305 
306 	for (i = 0; i < pevent->nr_events; i++) {
307 		event = pevent->events[i];
308 		if (event_match(event, sys_name ? &sreg : NULL, &ereg)) {
309 			match = 1;
310 			add_event(events, event);
311 		}
312 	}
313 
314 	regfree(&ereg);
315 	if (sys_name)
316 		regfree(&sreg);
317 
318 	if (!match)
319 		return -1;
320 
321 	return 0;
322 }
323 
free_events(struct event_list * events)324 static void free_events(struct event_list *events)
325 {
326 	struct event_list *event;
327 
328 	while (events) {
329 		event = events;
330 		events = events->next;
331 		free(event);
332 	}
333 }
334 
335 static struct filter_arg *
create_arg_item(struct event_format * event,const char * token,enum event_type type,char ** error_str)336 create_arg_item(struct event_format *event, const char *token,
337 		enum event_type type, char **error_str)
338 {
339 	struct format_field *field;
340 	struct filter_arg *arg;
341 
342 	arg = allocate_arg();
343 
344 	switch (type) {
345 
346 	case EVENT_SQUOTE:
347 	case EVENT_DQUOTE:
348 		arg->type = FILTER_ARG_VALUE;
349 		arg->value.type =
350 			type == EVENT_DQUOTE ? FILTER_STRING : FILTER_CHAR;
351 		arg->value.str = strdup(token);
352 		if (!arg->value.str)
353 			die("malloc string");
354 		break;
355 	case EVENT_ITEM:
356 		/* if it is a number, then convert it */
357 		if (isdigit(token[0])) {
358 			arg->type = FILTER_ARG_VALUE;
359 			arg->value.type = FILTER_NUMBER;
360 			arg->value.val = strtoull(token, NULL, 0);
361 			break;
362 		}
363 		/* Consider this a field */
364 		field = pevent_find_any_field(event, token);
365 		if (!field) {
366 			if (strcmp(token, COMM) != 0) {
367 				/* not a field, Make it false */
368 				arg->type = FILTER_ARG_BOOLEAN;
369 				arg->boolean.value = FILTER_FALSE;
370 				break;
371 			}
372 			/* If token is 'COMM' then it is special */
373 			field = &comm;
374 		}
375 		arg->type = FILTER_ARG_FIELD;
376 		arg->field.field = field;
377 		break;
378 	default:
379 		free_arg(arg);
380 		show_error(error_str, "expected a value but found %s",
381 			   token);
382 		return NULL;
383 	}
384 	return arg;
385 }
386 
387 static struct filter_arg *
create_arg_op(enum filter_op_type btype)388 create_arg_op(enum filter_op_type btype)
389 {
390 	struct filter_arg *arg;
391 
392 	arg = allocate_arg();
393 	arg->type = FILTER_ARG_OP;
394 	arg->op.type = btype;
395 
396 	return arg;
397 }
398 
399 static struct filter_arg *
create_arg_exp(enum filter_exp_type etype)400 create_arg_exp(enum filter_exp_type etype)
401 {
402 	struct filter_arg *arg;
403 
404 	arg = allocate_arg();
405 	arg->type = FILTER_ARG_EXP;
406 	arg->op.type = etype;
407 
408 	return arg;
409 }
410 
411 static struct filter_arg *
create_arg_cmp(enum filter_exp_type etype)412 create_arg_cmp(enum filter_exp_type etype)
413 {
414 	struct filter_arg *arg;
415 
416 	arg = allocate_arg();
417 	/* Use NUM and change if necessary */
418 	arg->type = FILTER_ARG_NUM;
419 	arg->op.type = etype;
420 
421 	return arg;
422 }
423 
add_right(struct filter_arg * op,struct filter_arg * arg,char ** error_str)424 static int add_right(struct filter_arg *op, struct filter_arg *arg,
425 		     char **error_str)
426 {
427 	struct filter_arg *left;
428 	char *str;
429 	int op_type;
430 	int ret;
431 
432 	switch (op->type) {
433 	case FILTER_ARG_EXP:
434 		if (op->exp.right)
435 			goto out_fail;
436 		op->exp.right = arg;
437 		break;
438 
439 	case FILTER_ARG_OP:
440 		if (op->op.right)
441 			goto out_fail;
442 		op->op.right = arg;
443 		break;
444 
445 	case FILTER_ARG_NUM:
446 		if (op->op.right)
447 			goto out_fail;
448 		/*
449 		 * The arg must be num, str, or field
450 		 */
451 		switch (arg->type) {
452 		case FILTER_ARG_VALUE:
453 		case FILTER_ARG_FIELD:
454 			break;
455 		default:
456 			show_error(error_str,
457 				   "Illegal rvalue");
458 			return -1;
459 		}
460 
461 		/*
462 		 * Depending on the type, we may need to
463 		 * convert this to a string or regex.
464 		 */
465 		switch (arg->value.type) {
466 		case FILTER_CHAR:
467 			/*
468 			 * A char should be converted to number if
469 			 * the string is 1 byte, and the compare
470 			 * is not a REGEX.
471 			 */
472 			if (strlen(arg->value.str) == 1 &&
473 			    op->num.type != FILTER_CMP_REGEX &&
474 			    op->num.type != FILTER_CMP_NOT_REGEX) {
475 				arg->value.type = FILTER_NUMBER;
476 				goto do_int;
477 			}
478 			/* fall through */
479 		case FILTER_STRING:
480 
481 			/* convert op to a string arg */
482 			op_type = op->num.type;
483 			left = op->num.left;
484 			str = arg->value.str;
485 
486 			/* reset the op for the new field */
487 			memset(op, 0, sizeof(*op));
488 
489 			/*
490 			 * If left arg was a field not found then
491 			 * NULL the entire op.
492 			 */
493 			if (left->type == FILTER_ARG_BOOLEAN) {
494 				free_arg(left);
495 				free_arg(arg);
496 				op->type = FILTER_ARG_BOOLEAN;
497 				op->boolean.value = FILTER_FALSE;
498 				break;
499 			}
500 
501 			/* Left arg must be a field */
502 			if (left->type != FILTER_ARG_FIELD) {
503 				show_error(error_str,
504 					   "Illegal lvalue for string comparison");
505 				return -1;
506 			}
507 
508 			/* Make sure this is a valid string compare */
509 			switch (op_type) {
510 			case FILTER_CMP_EQ:
511 				op_type = FILTER_CMP_MATCH;
512 				break;
513 			case FILTER_CMP_NE:
514 				op_type = FILTER_CMP_NOT_MATCH;
515 				break;
516 
517 			case FILTER_CMP_REGEX:
518 			case FILTER_CMP_NOT_REGEX:
519 				ret = regcomp(&op->str.reg, str, REG_ICASE|REG_NOSUB);
520 				if (ret) {
521 					show_error(error_str,
522 						   "RegEx '%s' did not compute",
523 						   str);
524 					return -1;
525 				}
526 				break;
527 			default:
528 				show_error(error_str,
529 					   "Illegal comparison for string");
530 				return -1;
531 			}
532 
533 			op->type = FILTER_ARG_STR;
534 			op->str.type = op_type;
535 			op->str.field = left->field.field;
536 			op->str.val = strdup(str);
537 			if (!op->str.val)
538 				die("malloc string");
539 			/*
540 			 * Need a buffer to copy data for tests
541 			 */
542 			op->str.buffer = malloc_or_die(op->str.field->size + 1);
543 			/* Null terminate this buffer */
544 			op->str.buffer[op->str.field->size] = 0;
545 
546 			/* We no longer have left or right args */
547 			free_arg(arg);
548 			free_arg(left);
549 
550 			break;
551 
552 		case FILTER_NUMBER:
553 
554  do_int:
555 			switch (op->num.type) {
556 			case FILTER_CMP_REGEX:
557 			case FILTER_CMP_NOT_REGEX:
558 				show_error(error_str,
559 					   "Op not allowed with integers");
560 				return -1;
561 
562 			default:
563 				break;
564 			}
565 
566 			/* numeric compare */
567 			op->num.right = arg;
568 			break;
569 		default:
570 			goto out_fail;
571 		}
572 		break;
573 	default:
574 		goto out_fail;
575 	}
576 
577 	return 0;
578 
579  out_fail:
580 	show_error(error_str,
581 		   "Syntax error");
582 	return -1;
583 }
584 
585 static struct filter_arg *
rotate_op_right(struct filter_arg * a,struct filter_arg * b)586 rotate_op_right(struct filter_arg *a, struct filter_arg *b)
587 {
588 	struct filter_arg *arg;
589 
590 	arg = a->op.right;
591 	a->op.right = b;
592 	return arg;
593 }
594 
add_left(struct filter_arg * op,struct filter_arg * arg)595 static int add_left(struct filter_arg *op, struct filter_arg *arg)
596 {
597 	switch (op->type) {
598 	case FILTER_ARG_EXP:
599 		if (arg->type == FILTER_ARG_OP)
600 			arg = rotate_op_right(arg, op);
601 		op->exp.left = arg;
602 		break;
603 
604 	case FILTER_ARG_OP:
605 		op->op.left = arg;
606 		break;
607 	case FILTER_ARG_NUM:
608 		if (arg->type == FILTER_ARG_OP)
609 			arg = rotate_op_right(arg, op);
610 
611 		/* left arg of compares must be a field */
612 		if (arg->type != FILTER_ARG_FIELD &&
613 		    arg->type != FILTER_ARG_BOOLEAN)
614 			return -1;
615 		op->num.left = arg;
616 		break;
617 	default:
618 		return -1;
619 	}
620 	return 0;
621 }
622 
623 enum op_type {
624 	OP_NONE,
625 	OP_BOOL,
626 	OP_NOT,
627 	OP_EXP,
628 	OP_CMP,
629 };
630 
process_op(const char * token,enum filter_op_type * btype,enum filter_cmp_type * ctype,enum filter_exp_type * etype)631 static enum op_type process_op(const char *token,
632 			       enum filter_op_type *btype,
633 			       enum filter_cmp_type *ctype,
634 			       enum filter_exp_type *etype)
635 {
636 	*btype = FILTER_OP_NOT;
637 	*etype = FILTER_EXP_NONE;
638 	*ctype = FILTER_CMP_NONE;
639 
640 	if (strcmp(token, "&&") == 0)
641 		*btype = FILTER_OP_AND;
642 	else if (strcmp(token, "||") == 0)
643 		*btype = FILTER_OP_OR;
644 	else if (strcmp(token, "!") == 0)
645 		return OP_NOT;
646 
647 	if (*btype != FILTER_OP_NOT)
648 		return OP_BOOL;
649 
650 	/* Check for value expressions */
651 	if (strcmp(token, "+") == 0) {
652 		*etype = FILTER_EXP_ADD;
653 	} else if (strcmp(token, "-") == 0) {
654 		*etype = FILTER_EXP_SUB;
655 	} else if (strcmp(token, "*") == 0) {
656 		*etype = FILTER_EXP_MUL;
657 	} else if (strcmp(token, "/") == 0) {
658 		*etype = FILTER_EXP_DIV;
659 	} else if (strcmp(token, "%") == 0) {
660 		*etype = FILTER_EXP_MOD;
661 	} else if (strcmp(token, ">>") == 0) {
662 		*etype = FILTER_EXP_RSHIFT;
663 	} else if (strcmp(token, "<<") == 0) {
664 		*etype = FILTER_EXP_LSHIFT;
665 	} else if (strcmp(token, "&") == 0) {
666 		*etype = FILTER_EXP_AND;
667 	} else if (strcmp(token, "|") == 0) {
668 		*etype = FILTER_EXP_OR;
669 	} else if (strcmp(token, "^") == 0) {
670 		*etype = FILTER_EXP_XOR;
671 	} else if (strcmp(token, "~") == 0)
672 		*etype = FILTER_EXP_NOT;
673 
674 	if (*etype != FILTER_EXP_NONE)
675 		return OP_EXP;
676 
677 	/* Check for compares */
678 	if (strcmp(token, "==") == 0)
679 		*ctype = FILTER_CMP_EQ;
680 	else if (strcmp(token, "!=") == 0)
681 		*ctype = FILTER_CMP_NE;
682 	else if (strcmp(token, "<") == 0)
683 		*ctype = FILTER_CMP_LT;
684 	else if (strcmp(token, ">") == 0)
685 		*ctype = FILTER_CMP_GT;
686 	else if (strcmp(token, "<=") == 0)
687 		*ctype = FILTER_CMP_LE;
688 	else if (strcmp(token, ">=") == 0)
689 		*ctype = FILTER_CMP_GE;
690 	else if (strcmp(token, "=~") == 0)
691 		*ctype = FILTER_CMP_REGEX;
692 	else if (strcmp(token, "!~") == 0)
693 		*ctype = FILTER_CMP_NOT_REGEX;
694 	else
695 		return OP_NONE;
696 
697 	return OP_CMP;
698 }
699 
check_op_done(struct filter_arg * arg)700 static int check_op_done(struct filter_arg *arg)
701 {
702 	switch (arg->type) {
703 	case FILTER_ARG_EXP:
704 		return arg->exp.right != NULL;
705 
706 	case FILTER_ARG_OP:
707 		return arg->op.right != NULL;
708 
709 	case FILTER_ARG_NUM:
710 		return arg->num.right != NULL;
711 
712 	case FILTER_ARG_STR:
713 		/* A string conversion is always done */
714 		return 1;
715 
716 	case FILTER_ARG_BOOLEAN:
717 		/* field not found, is ok */
718 		return 1;
719 
720 	default:
721 		return 0;
722 	}
723 }
724 
725 enum filter_vals {
726 	FILTER_VAL_NORM,
727 	FILTER_VAL_FALSE,
728 	FILTER_VAL_TRUE,
729 };
730 
reparent_op_arg(struct filter_arg * parent,struct filter_arg * old_child,struct filter_arg * arg)731 void reparent_op_arg(struct filter_arg *parent, struct filter_arg *old_child,
732 		  struct filter_arg *arg)
733 {
734 	struct filter_arg *other_child;
735 	struct filter_arg **ptr;
736 
737 	if (parent->type != FILTER_ARG_OP &&
738 	    arg->type != FILTER_ARG_OP)
739 		die("can not reparent other than OP");
740 
741 	/* Get the sibling */
742 	if (old_child->op.right == arg) {
743 		ptr = &old_child->op.right;
744 		other_child = old_child->op.left;
745 	} else if (old_child->op.left == arg) {
746 		ptr = &old_child->op.left;
747 		other_child = old_child->op.right;
748 	} else
749 		die("Error in reparent op, find other child");
750 
751 	/* Detach arg from old_child */
752 	*ptr = NULL;
753 
754 	/* Check for root */
755 	if (parent == old_child) {
756 		free_arg(other_child);
757 		*parent = *arg;
758 		/* Free arg without recussion */
759 		free(arg);
760 		return;
761 	}
762 
763 	if (parent->op.right == old_child)
764 		ptr = &parent->op.right;
765 	else if (parent->op.left == old_child)
766 		ptr = &parent->op.left;
767 	else
768 		die("Error in reparent op");
769 	*ptr = arg;
770 
771 	free_arg(old_child);
772 }
773 
test_arg(struct filter_arg * parent,struct filter_arg * arg)774 enum filter_vals test_arg(struct filter_arg *parent, struct filter_arg *arg)
775 {
776 	enum filter_vals lval, rval;
777 
778 	switch (arg->type) {
779 
780 		/* bad case */
781 	case FILTER_ARG_BOOLEAN:
782 		return FILTER_VAL_FALSE + arg->boolean.value;
783 
784 		/* good cases: */
785 	case FILTER_ARG_STR:
786 	case FILTER_ARG_VALUE:
787 	case FILTER_ARG_FIELD:
788 		return FILTER_VAL_NORM;
789 
790 	case FILTER_ARG_EXP:
791 		lval = test_arg(arg, arg->exp.left);
792 		if (lval != FILTER_VAL_NORM)
793 			return lval;
794 		rval = test_arg(arg, arg->exp.right);
795 		if (rval != FILTER_VAL_NORM)
796 			return rval;
797 		return FILTER_VAL_NORM;
798 
799 	case FILTER_ARG_NUM:
800 		lval = test_arg(arg, arg->num.left);
801 		if (lval != FILTER_VAL_NORM)
802 			return lval;
803 		rval = test_arg(arg, arg->num.right);
804 		if (rval != FILTER_VAL_NORM)
805 			return rval;
806 		return FILTER_VAL_NORM;
807 
808 	case FILTER_ARG_OP:
809 		if (arg->op.type != FILTER_OP_NOT) {
810 			lval = test_arg(arg, arg->op.left);
811 			switch (lval) {
812 			case FILTER_VAL_NORM:
813 				break;
814 			case FILTER_VAL_TRUE:
815 				if (arg->op.type == FILTER_OP_OR)
816 					return FILTER_VAL_TRUE;
817 				rval = test_arg(arg, arg->op.right);
818 				if (rval != FILTER_VAL_NORM)
819 					return rval;
820 
821 				reparent_op_arg(parent, arg, arg->op.right);
822 				return FILTER_VAL_NORM;
823 
824 			case FILTER_VAL_FALSE:
825 				if (arg->op.type == FILTER_OP_AND)
826 					return FILTER_VAL_FALSE;
827 				rval = test_arg(arg, arg->op.right);
828 				if (rval != FILTER_VAL_NORM)
829 					return rval;
830 
831 				reparent_op_arg(parent, arg, arg->op.right);
832 				return FILTER_VAL_NORM;
833 			}
834 		}
835 
836 		rval = test_arg(arg, arg->op.right);
837 		switch (rval) {
838 		case FILTER_VAL_NORM:
839 			break;
840 		case FILTER_VAL_TRUE:
841 			if (arg->op.type == FILTER_OP_OR)
842 				return FILTER_VAL_TRUE;
843 			if (arg->op.type == FILTER_OP_NOT)
844 				return FILTER_VAL_FALSE;
845 
846 			reparent_op_arg(parent, arg, arg->op.left);
847 			return FILTER_VAL_NORM;
848 
849 		case FILTER_VAL_FALSE:
850 			if (arg->op.type == FILTER_OP_AND)
851 				return FILTER_VAL_FALSE;
852 			if (arg->op.type == FILTER_OP_NOT)
853 				return FILTER_VAL_TRUE;
854 
855 			reparent_op_arg(parent, arg, arg->op.left);
856 			return FILTER_VAL_NORM;
857 		}
858 
859 		return FILTER_VAL_NORM;
860 	default:
861 		die("bad arg in filter tree");
862 	}
863 	return FILTER_VAL_NORM;
864 }
865 
866 /* Remove any unknown event fields */
collapse_tree(struct filter_arg * arg)867 static struct filter_arg *collapse_tree(struct filter_arg *arg)
868 {
869 	enum filter_vals ret;
870 
871 	ret = test_arg(arg, arg);
872 	switch (ret) {
873 	case FILTER_VAL_NORM:
874 		return arg;
875 
876 	case FILTER_VAL_TRUE:
877 	case FILTER_VAL_FALSE:
878 		free_arg(arg);
879 		arg = allocate_arg();
880 		arg->type = FILTER_ARG_BOOLEAN;
881 		arg->boolean.value = ret == FILTER_VAL_TRUE;
882 	}
883 
884 	return arg;
885 }
886 
887 static int
process_filter(struct event_format * event,struct filter_arg ** parg,char ** error_str,int not)888 process_filter(struct event_format *event, struct filter_arg **parg,
889 	       char **error_str, int not)
890 {
891 	enum event_type type;
892 	char *token = NULL;
893 	struct filter_arg *current_op = NULL;
894 	struct filter_arg *current_exp = NULL;
895 	struct filter_arg *left_item = NULL;
896 	struct filter_arg *arg = NULL;
897 	enum op_type op_type;
898 	enum filter_op_type btype;
899 	enum filter_exp_type etype;
900 	enum filter_cmp_type ctype;
901 	int ret;
902 
903 	*parg = NULL;
904 
905 	do {
906 		free(token);
907 		type = read_token(&token);
908 		switch (type) {
909 		case EVENT_SQUOTE:
910 		case EVENT_DQUOTE:
911 		case EVENT_ITEM:
912 			arg = create_arg_item(event, token, type, error_str);
913 			if (!arg)
914 				goto fail;
915 			if (!left_item)
916 				left_item = arg;
917 			else if (current_exp) {
918 				ret = add_right(current_exp, arg, error_str);
919 				if (ret < 0)
920 					goto fail;
921 				left_item = NULL;
922 				/* Not's only one one expression */
923 				if (not) {
924 					arg = NULL;
925 					if (current_op)
926 						goto fail_print;
927 					free(token);
928 					*parg = current_exp;
929 					return 0;
930 				}
931 			} else
932 				goto fail_print;
933 			arg = NULL;
934 			break;
935 
936 		case EVENT_DELIM:
937 			if (*token == ',') {
938 				show_error(error_str,
939 					   "Illegal token ','");
940 				goto fail;
941 			}
942 
943 			if (*token == '(') {
944 				if (left_item) {
945 					show_error(error_str,
946 						   "Open paren can not come after item");
947 					goto fail;
948 				}
949 				if (current_exp) {
950 					show_error(error_str,
951 						   "Open paren can not come after expression");
952 					goto fail;
953 				}
954 
955 				ret = process_filter(event, &arg, error_str, 0);
956 				if (ret != 1) {
957 					if (ret == 0)
958 						show_error(error_str,
959 							   "Unbalanced number of '('");
960 					goto fail;
961 				}
962 				ret = 0;
963 
964 				/* A not wants just one expression */
965 				if (not) {
966 					if (current_op)
967 						goto fail_print;
968 					*parg = arg;
969 					return 0;
970 				}
971 
972 				if (current_op)
973 					ret = add_right(current_op, arg, error_str);
974 				else
975 					current_exp = arg;
976 
977 				if (ret < 0)
978 					goto fail;
979 
980 			} else { /* ')' */
981 				if (!current_op && !current_exp)
982 					goto fail_print;
983 
984 				/* Make sure everything is finished at this level */
985 				if (current_exp && !check_op_done(current_exp))
986 					goto fail_print;
987 				if (current_op && !check_op_done(current_op))
988 					goto fail_print;
989 
990 				if (current_op)
991 					*parg = current_op;
992 				else
993 					*parg = current_exp;
994 				return 1;
995 			}
996 			break;
997 
998 		case EVENT_OP:
999 			op_type = process_op(token, &btype, &ctype, &etype);
1000 
1001 			/* All expect a left arg except for NOT */
1002 			switch (op_type) {
1003 			case OP_BOOL:
1004 				/* Logic ops need a left expression */
1005 				if (!current_exp && !current_op)
1006 					goto fail_print;
1007 				/* fall through */
1008 			case OP_NOT:
1009 				/* logic only processes ops and exp */
1010 				if (left_item)
1011 					goto fail_print;
1012 				break;
1013 			case OP_EXP:
1014 			case OP_CMP:
1015 				if (!left_item)
1016 					goto fail_print;
1017 				break;
1018 			case OP_NONE:
1019 				show_error(error_str,
1020 					   "Unknown op token %s", token);
1021 				goto fail;
1022 			}
1023 
1024 			ret = 0;
1025 			switch (op_type) {
1026 			case OP_BOOL:
1027 				arg = create_arg_op(btype);
1028 				if (current_op)
1029 					ret = add_left(arg, current_op);
1030 				else
1031 					ret = add_left(arg, current_exp);
1032 				current_op = arg;
1033 				current_exp = NULL;
1034 				break;
1035 
1036 			case OP_NOT:
1037 				arg = create_arg_op(btype);
1038 				if (current_op)
1039 					ret = add_right(current_op, arg, error_str);
1040 				if (ret < 0)
1041 					goto fail;
1042 				current_exp = arg;
1043 				ret = process_filter(event, &arg, error_str, 1);
1044 				if (ret < 0)
1045 					goto fail;
1046 				ret = add_right(current_exp, arg, error_str);
1047 				if (ret < 0)
1048 					goto fail;
1049 				break;
1050 
1051 			case OP_EXP:
1052 			case OP_CMP:
1053 				if (op_type == OP_EXP)
1054 					arg = create_arg_exp(etype);
1055 				else
1056 					arg = create_arg_cmp(ctype);
1057 
1058 				if (current_op)
1059 					ret = add_right(current_op, arg, error_str);
1060 				if (ret < 0)
1061 					goto fail;
1062 				ret = add_left(arg, left_item);
1063 				if (ret < 0) {
1064 					arg = NULL;
1065 					goto fail_print;
1066 				}
1067 				current_exp = arg;
1068 				break;
1069 			default:
1070 				break;
1071 			}
1072 			arg = NULL;
1073 			if (ret < 0)
1074 				goto fail_print;
1075 			break;
1076 		case EVENT_NONE:
1077 			break;
1078 		default:
1079 			goto fail_print;
1080 		}
1081 	} while (type != EVENT_NONE);
1082 
1083 	if (!current_op && !current_exp)
1084 		goto fail_print;
1085 
1086 	if (!current_op)
1087 		current_op = current_exp;
1088 
1089 	current_op = collapse_tree(current_op);
1090 
1091 	*parg = current_op;
1092 
1093 	return 0;
1094 
1095  fail_print:
1096 	show_error(error_str, "Syntax error");
1097  fail:
1098 	free_arg(current_op);
1099 	free_arg(current_exp);
1100 	free_arg(arg);
1101 	free(token);
1102 	return -1;
1103 }
1104 
1105 static int
process_event(struct event_format * event,const char * filter_str,struct filter_arg ** parg,char ** error_str)1106 process_event(struct event_format *event, const char *filter_str,
1107 	      struct filter_arg **parg, char **error_str)
1108 {
1109 	int ret;
1110 
1111 	pevent_buffer_init(filter_str, strlen(filter_str));
1112 
1113 	ret = process_filter(event, parg, error_str, 0);
1114 	if (ret == 1) {
1115 		show_error(error_str,
1116 			   "Unbalanced number of ')'");
1117 		return -1;
1118 	}
1119 	if (ret < 0)
1120 		return ret;
1121 
1122 	/* If parg is NULL, then make it into FALSE */
1123 	if (!*parg) {
1124 		*parg = allocate_arg();
1125 		(*parg)->type = FILTER_ARG_BOOLEAN;
1126 		(*parg)->boolean.value = FILTER_FALSE;
1127 	}
1128 
1129 	return 0;
1130 }
1131 
filter_event(struct event_filter * filter,struct event_format * event,const char * filter_str,char ** error_str)1132 static int filter_event(struct event_filter *filter,
1133 			struct event_format *event,
1134 			const char *filter_str, char **error_str)
1135 {
1136 	struct filter_type *filter_type;
1137 	struct filter_arg *arg;
1138 	int ret;
1139 
1140 	if (filter_str) {
1141 		ret = process_event(event, filter_str, &arg, error_str);
1142 		if (ret < 0)
1143 			return ret;
1144 
1145 	} else {
1146 		/* just add a TRUE arg */
1147 		arg = allocate_arg();
1148 		arg->type = FILTER_ARG_BOOLEAN;
1149 		arg->boolean.value = FILTER_TRUE;
1150 	}
1151 
1152 	filter_type = add_filter_type(filter, event->id);
1153 	if (filter_type->filter)
1154 		free_arg(filter_type->filter);
1155 	filter_type->filter = arg;
1156 
1157 	return 0;
1158 }
1159 
1160 /**
1161  * pevent_filter_add_filter_str - add a new filter
1162  * @filter: the event filter to add to
1163  * @filter_str: the filter string that contains the filter
1164  * @error_str: string containing reason for failed filter
1165  *
1166  * Returns 0 if the filter was successfully added
1167  *   -1 if there was an error.
1168  *
1169  * On error, if @error_str points to a string pointer,
1170  * it is set to the reason that the filter failed.
1171  * This string must be freed with "free".
1172  */
pevent_filter_add_filter_str(struct event_filter * filter,const char * filter_str,char ** error_str)1173 int pevent_filter_add_filter_str(struct event_filter *filter,
1174 				 const char *filter_str,
1175 				 char **error_str)
1176 {
1177 	struct pevent *pevent = filter->pevent;
1178 	struct event_list *event;
1179 	struct event_list *events = NULL;
1180 	const char *filter_start;
1181 	const char *next_event;
1182 	char *this_event;
1183 	char *event_name = NULL;
1184 	char *sys_name = NULL;
1185 	char *sp;
1186 	int rtn = 0;
1187 	int len;
1188 	int ret;
1189 
1190 	/* clear buffer to reset show error */
1191 	pevent_buffer_init("", 0);
1192 
1193 	if (error_str)
1194 		*error_str = NULL;
1195 
1196 	filter_start = strchr(filter_str, ':');
1197 	if (filter_start)
1198 		len = filter_start - filter_str;
1199 	else
1200 		len = strlen(filter_str);
1201 
1202 
1203 	do {
1204 		next_event = strchr(filter_str, ',');
1205 		if (next_event &&
1206 		    (!filter_start || next_event < filter_start))
1207 			len = next_event - filter_str;
1208 		else if (filter_start)
1209 			len = filter_start - filter_str;
1210 		else
1211 			len = strlen(filter_str);
1212 
1213 		this_event = malloc_or_die(len + 1);
1214 		memcpy(this_event, filter_str, len);
1215 		this_event[len] = 0;
1216 
1217 		if (next_event)
1218 			next_event++;
1219 
1220 		filter_str = next_event;
1221 
1222 		sys_name = strtok_r(this_event, "/", &sp);
1223 		event_name = strtok_r(NULL, "/", &sp);
1224 
1225 		if (!sys_name) {
1226 			show_error(error_str, "No filter found");
1227 			/* This can only happen when events is NULL, but still */
1228 			free_events(events);
1229 			free(this_event);
1230 			return -1;
1231 		}
1232 
1233 		/* Find this event */
1234 		ret = find_event(pevent, &events, strim(sys_name), strim(event_name));
1235 		if (ret < 0) {
1236 			if (event_name)
1237 				show_error(error_str,
1238 					   "No event found under '%s.%s'",
1239 					   sys_name, event_name);
1240 			else
1241 				show_error(error_str,
1242 					   "No event found under '%s'",
1243 					   sys_name);
1244 			free_events(events);
1245 			free(this_event);
1246 			return -1;
1247 		}
1248 		free(this_event);
1249 	} while (filter_str);
1250 
1251 	/* Skip the ':' */
1252 	if (filter_start)
1253 		filter_start++;
1254 
1255 	/* filter starts here */
1256 	for (event = events; event; event = event->next) {
1257 		ret = filter_event(filter, event->event, filter_start,
1258 				   error_str);
1259 		/* Failures are returned if a parse error happened */
1260 		if (ret < 0)
1261 			rtn = ret;
1262 
1263 		if (ret >= 0 && pevent->test_filters) {
1264 			char *test;
1265 			test = pevent_filter_make_string(filter, event->event->id);
1266 			printf(" '%s: %s'\n", event->event->name, test);
1267 			free(test);
1268 		}
1269 	}
1270 
1271 	free_events(events);
1272 
1273 	if (rtn >= 0 && pevent->test_filters)
1274 		exit(0);
1275 
1276 	return rtn;
1277 }
1278 
free_filter_type(struct filter_type * filter_type)1279 static void free_filter_type(struct filter_type *filter_type)
1280 {
1281 	free_arg(filter_type->filter);
1282 }
1283 
1284 /**
1285  * pevent_filter_remove_event - remove a filter for an event
1286  * @filter: the event filter to remove from
1287  * @event_id: the event to remove a filter for
1288  *
1289  * Removes the filter saved for an event defined by @event_id
1290  * from the @filter.
1291  *
1292  * Returns 1: if an event was removed
1293  *   0: if the event was not found
1294  */
pevent_filter_remove_event(struct event_filter * filter,int event_id)1295 int pevent_filter_remove_event(struct event_filter *filter,
1296 			       int event_id)
1297 {
1298 	struct filter_type *filter_type;
1299 	unsigned long len;
1300 
1301 	if (!filter->filters)
1302 		return 0;
1303 
1304 	filter_type = find_filter_type(filter, event_id);
1305 
1306 	if (!filter_type)
1307 		return 0;
1308 
1309 	free_filter_type(filter_type);
1310 
1311 	/* The filter_type points into the event_filters array */
1312 	len = (unsigned long)(filter->event_filters + filter->filters) -
1313 		(unsigned long)(filter_type + 1);
1314 
1315 	memmove(filter_type, filter_type + 1, len);
1316 	filter->filters--;
1317 
1318 	memset(&filter->event_filters[filter->filters], 0,
1319 	       sizeof(*filter_type));
1320 
1321 	return 1;
1322 }
1323 
1324 /**
1325  * pevent_filter_reset - clear all filters in a filter
1326  * @filter: the event filter to reset
1327  *
1328  * Removes all filters from a filter and resets it.
1329  */
pevent_filter_reset(struct event_filter * filter)1330 void pevent_filter_reset(struct event_filter *filter)
1331 {
1332 	int i;
1333 
1334 	for (i = 0; i < filter->filters; i++)
1335 		free_filter_type(&filter->event_filters[i]);
1336 
1337 	free(filter->event_filters);
1338 	filter->filters = 0;
1339 	filter->event_filters = NULL;
1340 }
1341 
pevent_filter_free(struct event_filter * filter)1342 void pevent_filter_free(struct event_filter *filter)
1343 {
1344 	pevent_unref(filter->pevent);
1345 
1346 	pevent_filter_reset(filter);
1347 
1348 	free(filter);
1349 }
1350 
1351 static char *arg_to_str(struct event_filter *filter, struct filter_arg *arg);
1352 
copy_filter_type(struct event_filter * filter,struct event_filter * source,struct filter_type * filter_type)1353 static int copy_filter_type(struct event_filter *filter,
1354 			     struct event_filter *source,
1355 			     struct filter_type *filter_type)
1356 {
1357 	struct filter_arg *arg;
1358 	struct event_format *event;
1359 	const char *sys;
1360 	const char *name;
1361 	char *str;
1362 
1363 	/* Can't assume that the pevent's are the same */
1364 	sys = filter_type->event->system;
1365 	name = filter_type->event->name;
1366 	event = pevent_find_event_by_name(filter->pevent, sys, name);
1367 	if (!event)
1368 		return -1;
1369 
1370 	str = arg_to_str(source, filter_type->filter);
1371 	if (!str)
1372 		return -1;
1373 
1374 	if (strcmp(str, "TRUE") == 0 || strcmp(str, "FALSE") == 0) {
1375 		/* Add trivial event */
1376 		arg = allocate_arg();
1377 		arg->type = FILTER_ARG_BOOLEAN;
1378 		if (strcmp(str, "TRUE") == 0)
1379 			arg->boolean.value = 1;
1380 		else
1381 			arg->boolean.value = 0;
1382 
1383 		filter_type = add_filter_type(filter, event->id);
1384 		filter_type->filter = arg;
1385 
1386 		free(str);
1387 		return 0;
1388 	}
1389 
1390 	filter_event(filter, event, str, NULL);
1391 	free(str);
1392 
1393 	return 0;
1394 }
1395 
1396 /**
1397  * pevent_filter_copy - copy a filter using another filter
1398  * @dest - the filter to copy to
1399  * @source - the filter to copy from
1400  *
1401  * Returns 0 on success and -1 if not all filters were copied
1402  */
pevent_filter_copy(struct event_filter * dest,struct event_filter * source)1403 int pevent_filter_copy(struct event_filter *dest, struct event_filter *source)
1404 {
1405 	int ret = 0;
1406 	int i;
1407 
1408 	pevent_filter_reset(dest);
1409 
1410 	for (i = 0; i < source->filters; i++) {
1411 		if (copy_filter_type(dest, source, &source->event_filters[i]))
1412 			ret = -1;
1413 	}
1414 	return ret;
1415 }
1416 
1417 
1418 /**
1419  * pevent_update_trivial - update the trivial filters with the given filter
1420  * @dest - the filter to update
1421  * @source - the filter as the source of the update
1422  * @type - the type of trivial filter to update.
1423  *
1424  * Scan dest for trivial events matching @type to replace with the source.
1425  *
1426  * Returns 0 on success and -1 if there was a problem updating, but
1427  *   events may have still been updated on error.
1428  */
pevent_update_trivial(struct event_filter * dest,struct event_filter * source,enum filter_trivial_type type)1429 int pevent_update_trivial(struct event_filter *dest, struct event_filter *source,
1430 			  enum filter_trivial_type type)
1431 {
1432 	struct pevent *src_pevent;
1433 	struct pevent *dest_pevent;
1434 	struct event_format *event;
1435 	struct filter_type *filter_type;
1436 	struct filter_arg *arg;
1437 	char *str;
1438 	int i;
1439 
1440 	src_pevent = source->pevent;
1441 	dest_pevent = dest->pevent;
1442 
1443 	/* Do nothing if either of the filters has nothing to filter */
1444 	if (!dest->filters || !source->filters)
1445 		return 0;
1446 
1447 	for (i = 0; i < dest->filters; i++) {
1448 		filter_type = &dest->event_filters[i];
1449 		arg = filter_type->filter;
1450 		if (arg->type != FILTER_ARG_BOOLEAN)
1451 			continue;
1452 		if ((arg->boolean.value && type == FILTER_TRIVIAL_FALSE) ||
1453 		    (!arg->boolean.value && type == FILTER_TRIVIAL_TRUE))
1454 			continue;
1455 
1456 		event = filter_type->event;
1457 
1458 		if (src_pevent != dest_pevent) {
1459 			/* do a look up */
1460 			event = pevent_find_event_by_name(src_pevent,
1461 							  event->system,
1462 							  event->name);
1463 			if (!event)
1464 				return -1;
1465 		}
1466 
1467 		str = pevent_filter_make_string(source, event->id);
1468 		if (!str)
1469 			continue;
1470 
1471 		/* Don't bother if the filter is trivial too */
1472 		if (strcmp(str, "TRUE") != 0 && strcmp(str, "FALSE") != 0)
1473 			filter_event(dest, event, str, NULL);
1474 		free(str);
1475 	}
1476 	return 0;
1477 }
1478 
1479 /**
1480  * pevent_filter_clear_trivial - clear TRUE and FALSE filters
1481  * @filter: the filter to remove trivial filters from
1482  * @type: remove only true, false, or both
1483  *
1484  * Removes filters that only contain a TRUE or FALES boolean arg.
1485  */
pevent_filter_clear_trivial(struct event_filter * filter,enum filter_trivial_type type)1486 void pevent_filter_clear_trivial(struct event_filter *filter,
1487 				 enum filter_trivial_type type)
1488 {
1489 	struct filter_type *filter_type;
1490 	int count = 0;
1491 	int *ids = NULL;
1492 	int i;
1493 
1494 	if (!filter->filters)
1495 		return;
1496 
1497 	/*
1498 	 * Two steps, first get all ids with trivial filters.
1499 	 *  then remove those ids.
1500 	 */
1501 	for (i = 0; i < filter->filters; i++) {
1502 		filter_type = &filter->event_filters[i];
1503 		if (filter_type->filter->type != FILTER_ARG_BOOLEAN)
1504 			continue;
1505 		switch (type) {
1506 		case FILTER_TRIVIAL_FALSE:
1507 			if (filter_type->filter->boolean.value)
1508 				continue;
1509 		case FILTER_TRIVIAL_TRUE:
1510 			if (!filter_type->filter->boolean.value)
1511 				continue;
1512 		default:
1513 			break;
1514 		}
1515 
1516 		ids = realloc(ids, sizeof(*ids) * (count + 1));
1517 		if (!ids)
1518 			die("Can't allocate ids");
1519 		ids[count++] = filter_type->event_id;
1520 	}
1521 
1522 	if (!count)
1523 		return;
1524 
1525 	for (i = 0; i < count; i++)
1526 		pevent_filter_remove_event(filter, ids[i]);
1527 
1528 	free(ids);
1529 }
1530 
1531 /**
1532  * pevent_filter_event_has_trivial - return true event contains trivial filter
1533  * @filter: the filter with the information
1534  * @event_id: the id of the event to test
1535  * @type: trivial type to test for (TRUE, FALSE, EITHER)
1536  *
1537  * Returns 1 if the event contains a matching trivial type
1538  *  otherwise 0.
1539  */
pevent_filter_event_has_trivial(struct event_filter * filter,int event_id,enum filter_trivial_type type)1540 int pevent_filter_event_has_trivial(struct event_filter *filter,
1541 				    int event_id,
1542 				    enum filter_trivial_type type)
1543 {
1544 	struct filter_type *filter_type;
1545 
1546 	if (!filter->filters)
1547 		return 0;
1548 
1549 	filter_type = find_filter_type(filter, event_id);
1550 
1551 	if (!filter_type)
1552 		return 0;
1553 
1554 	if (filter_type->filter->type != FILTER_ARG_BOOLEAN)
1555 		return 0;
1556 
1557 	switch (type) {
1558 	case FILTER_TRIVIAL_FALSE:
1559 		return !filter_type->filter->boolean.value;
1560 
1561 	case FILTER_TRIVIAL_TRUE:
1562 		return filter_type->filter->boolean.value;
1563 	default:
1564 		return 1;
1565 	}
1566 }
1567 
1568 static int test_filter(struct event_format *event,
1569 		       struct filter_arg *arg, struct pevent_record *record);
1570 
1571 static const char *
get_comm(struct event_format * event,struct pevent_record * record)1572 get_comm(struct event_format *event, struct pevent_record *record)
1573 {
1574 	const char *comm;
1575 	int pid;
1576 
1577 	pid = pevent_data_pid(event->pevent, record);
1578 	comm = pevent_data_comm_from_pid(event->pevent, pid);
1579 	return comm;
1580 }
1581 
1582 static unsigned long long
get_value(struct event_format * event,struct format_field * field,struct pevent_record * record)1583 get_value(struct event_format *event,
1584 	  struct format_field *field, struct pevent_record *record)
1585 {
1586 	unsigned long long val;
1587 
1588 	/* Handle our dummy "comm" field */
1589 	if (field == &comm) {
1590 		const char *name;
1591 
1592 		name = get_comm(event, record);
1593 		return (unsigned long)name;
1594 	}
1595 
1596 	pevent_read_number_field(field, record->data, &val);
1597 
1598 	if (!(field->flags & FIELD_IS_SIGNED))
1599 		return val;
1600 
1601 	switch (field->size) {
1602 	case 1:
1603 		return (char)val;
1604 	case 2:
1605 		return (short)val;
1606 	case 4:
1607 		return (int)val;
1608 	case 8:
1609 		return (long long)val;
1610 	}
1611 	return val;
1612 }
1613 
1614 static unsigned long long
1615 get_arg_value(struct event_format *event, struct filter_arg *arg, struct pevent_record *record);
1616 
1617 static unsigned long long
get_exp_value(struct event_format * event,struct filter_arg * arg,struct pevent_record * record)1618 get_exp_value(struct event_format *event, struct filter_arg *arg, struct pevent_record *record)
1619 {
1620 	unsigned long long lval, rval;
1621 
1622 	lval = get_arg_value(event, arg->exp.left, record);
1623 	rval = get_arg_value(event, arg->exp.right, record);
1624 
1625 	switch (arg->exp.type) {
1626 	case FILTER_EXP_ADD:
1627 		return lval + rval;
1628 
1629 	case FILTER_EXP_SUB:
1630 		return lval - rval;
1631 
1632 	case FILTER_EXP_MUL:
1633 		return lval * rval;
1634 
1635 	case FILTER_EXP_DIV:
1636 		return lval / rval;
1637 
1638 	case FILTER_EXP_MOD:
1639 		return lval % rval;
1640 
1641 	case FILTER_EXP_RSHIFT:
1642 		return lval >> rval;
1643 
1644 	case FILTER_EXP_LSHIFT:
1645 		return lval << rval;
1646 
1647 	case FILTER_EXP_AND:
1648 		return lval & rval;
1649 
1650 	case FILTER_EXP_OR:
1651 		return lval | rval;
1652 
1653 	case FILTER_EXP_XOR:
1654 		return lval ^ rval;
1655 
1656 	case FILTER_EXP_NOT:
1657 	default:
1658 		die("error in exp");
1659 	}
1660 	return 0;
1661 }
1662 
1663 static unsigned long long
get_arg_value(struct event_format * event,struct filter_arg * arg,struct pevent_record * record)1664 get_arg_value(struct event_format *event, struct filter_arg *arg, struct pevent_record *record)
1665 {
1666 	switch (arg->type) {
1667 	case FILTER_ARG_FIELD:
1668 		return get_value(event, arg->field.field, record);
1669 
1670 	case FILTER_ARG_VALUE:
1671 		if (arg->value.type != FILTER_NUMBER)
1672 			die("must have number field!");
1673 		return arg->value.val;
1674 
1675 	case FILTER_ARG_EXP:
1676 		return get_exp_value(event, arg, record);
1677 
1678 	default:
1679 		die("oops in filter");
1680 	}
1681 	return 0;
1682 }
1683 
test_num(struct event_format * event,struct filter_arg * arg,struct pevent_record * record)1684 static int test_num(struct event_format *event,
1685 		    struct filter_arg *arg, struct pevent_record *record)
1686 {
1687 	unsigned long long lval, rval;
1688 
1689 	lval = get_arg_value(event, arg->num.left, record);
1690 	rval = get_arg_value(event, arg->num.right, record);
1691 
1692 	switch (arg->num.type) {
1693 	case FILTER_CMP_EQ:
1694 		return lval == rval;
1695 
1696 	case FILTER_CMP_NE:
1697 		return lval != rval;
1698 
1699 	case FILTER_CMP_GT:
1700 		return lval > rval;
1701 
1702 	case FILTER_CMP_LT:
1703 		return lval < rval;
1704 
1705 	case FILTER_CMP_GE:
1706 		return lval >= rval;
1707 
1708 	case FILTER_CMP_LE:
1709 		return lval <= rval;
1710 
1711 	default:
1712 		/* ?? */
1713 		return 0;
1714 	}
1715 }
1716 
get_field_str(struct filter_arg * arg,struct pevent_record * record)1717 static const char *get_field_str(struct filter_arg *arg, struct pevent_record *record)
1718 {
1719 	struct event_format *event;
1720 	struct pevent *pevent;
1721 	unsigned long long addr;
1722 	const char *val = NULL;
1723 	char hex[64];
1724 
1725 	/* If the field is not a string convert it */
1726 	if (arg->str.field->flags & FIELD_IS_STRING) {
1727 		val = record->data + arg->str.field->offset;
1728 
1729 		/*
1730 		 * We need to copy the data since we can't be sure the field
1731 		 * is null terminated.
1732 		 */
1733 		if (*(val + arg->str.field->size - 1)) {
1734 			/* copy it */
1735 			memcpy(arg->str.buffer, val, arg->str.field->size);
1736 			/* the buffer is already NULL terminated */
1737 			val = arg->str.buffer;
1738 		}
1739 
1740 	} else {
1741 		event = arg->str.field->event;
1742 		pevent = event->pevent;
1743 		addr = get_value(event, arg->str.field, record);
1744 
1745 		if (arg->str.field->flags & (FIELD_IS_POINTER | FIELD_IS_LONG))
1746 			/* convert to a kernel symbol */
1747 			val = pevent_find_function(pevent, addr);
1748 
1749 		if (val == NULL) {
1750 			/* just use the hex of the string name */
1751 			snprintf(hex, 64, "0x%llx", addr);
1752 			val = hex;
1753 		}
1754 	}
1755 
1756 	return val;
1757 }
1758 
test_str(struct event_format * event,struct filter_arg * arg,struct pevent_record * record)1759 static int test_str(struct event_format *event,
1760 		    struct filter_arg *arg, struct pevent_record *record)
1761 {
1762 	const char *val;
1763 
1764 	if (arg->str.field == &comm)
1765 		val = get_comm(event, record);
1766 	else
1767 		val = get_field_str(arg, record);
1768 
1769 	switch (arg->str.type) {
1770 	case FILTER_CMP_MATCH:
1771 		return strcmp(val, arg->str.val) == 0;
1772 
1773 	case FILTER_CMP_NOT_MATCH:
1774 		return strcmp(val, arg->str.val) != 0;
1775 
1776 	case FILTER_CMP_REGEX:
1777 		/* Returns zero on match */
1778 		return !regexec(&arg->str.reg, val, 0, NULL, 0);
1779 
1780 	case FILTER_CMP_NOT_REGEX:
1781 		return regexec(&arg->str.reg, val, 0, NULL, 0);
1782 
1783 	default:
1784 		/* ?? */
1785 		return 0;
1786 	}
1787 }
1788 
test_op(struct event_format * event,struct filter_arg * arg,struct pevent_record * record)1789 static int test_op(struct event_format *event,
1790 		   struct filter_arg *arg, struct pevent_record *record)
1791 {
1792 	switch (arg->op.type) {
1793 	case FILTER_OP_AND:
1794 		return test_filter(event, arg->op.left, record) &&
1795 			test_filter(event, arg->op.right, record);
1796 
1797 	case FILTER_OP_OR:
1798 		return test_filter(event, arg->op.left, record) ||
1799 			test_filter(event, arg->op.right, record);
1800 
1801 	case FILTER_OP_NOT:
1802 		return !test_filter(event, arg->op.right, record);
1803 
1804 	default:
1805 		/* ?? */
1806 		return 0;
1807 	}
1808 }
1809 
test_filter(struct event_format * event,struct filter_arg * arg,struct pevent_record * record)1810 static int test_filter(struct event_format *event,
1811 		       struct filter_arg *arg, struct pevent_record *record)
1812 {
1813 	switch (arg->type) {
1814 	case FILTER_ARG_BOOLEAN:
1815 		/* easy case */
1816 		return arg->boolean.value;
1817 
1818 	case FILTER_ARG_OP:
1819 		return test_op(event, arg, record);
1820 
1821 	case FILTER_ARG_NUM:
1822 		return test_num(event, arg, record);
1823 
1824 	case FILTER_ARG_STR:
1825 		return test_str(event, arg, record);
1826 
1827 	case FILTER_ARG_EXP:
1828 	case FILTER_ARG_VALUE:
1829 	case FILTER_ARG_FIELD:
1830 		/*
1831 		 * Expressions, fields and values evaluate
1832 		 * to true if they return non zero
1833 		 */
1834 		return !!get_arg_value(event, arg, record);
1835 
1836 	default:
1837 		die("oops!");
1838 		/* ?? */
1839 		return 0;
1840 	}
1841 }
1842 
1843 /**
1844  * pevent_event_filtered - return true if event has filter
1845  * @filter: filter struct with filter information
1846  * @event_id: event id to test if filter exists
1847  *
1848  * Returns 1 if filter found for @event_id
1849  *   otherwise 0;
1850  */
pevent_event_filtered(struct event_filter * filter,int event_id)1851 int pevent_event_filtered(struct event_filter *filter,
1852 			  int event_id)
1853 {
1854 	struct filter_type *filter_type;
1855 
1856 	if (!filter->filters)
1857 		return 0;
1858 
1859 	filter_type = find_filter_type(filter, event_id);
1860 
1861 	return filter_type ? 1 : 0;
1862 }
1863 
1864 /**
1865  * pevent_filter_match - test if a record matches a filter
1866  * @filter: filter struct with filter information
1867  * @record: the record to test against the filter
1868  *
1869  * Returns:
1870  *  1 - filter found for event and @record matches
1871  *  0 - filter found for event and @record does not match
1872  * -1 - no filter found for @record's event
1873  * -2 - if no filters exist
1874  */
pevent_filter_match(struct event_filter * filter,struct pevent_record * record)1875 int pevent_filter_match(struct event_filter *filter,
1876 			struct pevent_record *record)
1877 {
1878 	struct pevent *pevent = filter->pevent;
1879 	struct filter_type *filter_type;
1880 	int event_id;
1881 
1882 	if (!filter->filters)
1883 		return FILTER_NONE;
1884 
1885 	event_id = pevent_data_type(pevent, record);
1886 
1887 	filter_type = find_filter_type(filter, event_id);
1888 
1889 	if (!filter_type)
1890 		return FILTER_NOEXIST;
1891 
1892 	return test_filter(filter_type->event, filter_type->filter, record) ?
1893 		FILTER_MATCH : FILTER_MISS;
1894 }
1895 
op_to_str(struct event_filter * filter,struct filter_arg * arg)1896 static char *op_to_str(struct event_filter *filter, struct filter_arg *arg)
1897 {
1898 	char *str = NULL;
1899 	char *left = NULL;
1900 	char *right = NULL;
1901 	char *op = NULL;
1902 	int left_val = -1;
1903 	int right_val = -1;
1904 	int val;
1905 	int len;
1906 
1907 	switch (arg->op.type) {
1908 	case FILTER_OP_AND:
1909 		op = "&&";
1910 		/* fall through */
1911 	case FILTER_OP_OR:
1912 		if (!op)
1913 			op = "||";
1914 
1915 		left = arg_to_str(filter, arg->op.left);
1916 		right = arg_to_str(filter, arg->op.right);
1917 		if (!left || !right)
1918 			break;
1919 
1920 		/* Try to consolidate boolean values */
1921 		if (strcmp(left, "TRUE") == 0)
1922 			left_val = 1;
1923 		else if (strcmp(left, "FALSE") == 0)
1924 			left_val = 0;
1925 
1926 		if (strcmp(right, "TRUE") == 0)
1927 			right_val = 1;
1928 		else if (strcmp(right, "FALSE") == 0)
1929 			right_val = 0;
1930 
1931 		if (left_val >= 0) {
1932 			if ((arg->op.type == FILTER_OP_AND && !left_val) ||
1933 			    (arg->op.type == FILTER_OP_OR && left_val)) {
1934 				/* Just return left value */
1935 				str = left;
1936 				left = NULL;
1937 				break;
1938 			}
1939 			if (right_val >= 0) {
1940 				/* just evaluate this. */
1941 				val = 0;
1942 				switch (arg->op.type) {
1943 				case FILTER_OP_AND:
1944 					val = left_val && right_val;
1945 					break;
1946 				case FILTER_OP_OR:
1947 					val = left_val || right_val;
1948 					break;
1949 				default:
1950 					break;
1951 				}
1952 				str = malloc_or_die(6);
1953 				if (val)
1954 					strcpy(str, "TRUE");
1955 				else
1956 					strcpy(str, "FALSE");
1957 				break;
1958 			}
1959 		}
1960 		if (right_val >= 0) {
1961 			if ((arg->op.type == FILTER_OP_AND && !right_val) ||
1962 			    (arg->op.type == FILTER_OP_OR && right_val)) {
1963 				/* Just return right value */
1964 				str = right;
1965 				right = NULL;
1966 				break;
1967 			}
1968 			/* The right value is meaningless */
1969 			str = left;
1970 			left = NULL;
1971 			break;
1972 		}
1973 
1974 		len = strlen(left) + strlen(right) + strlen(op) + 10;
1975 		str = malloc_or_die(len);
1976 		snprintf(str, len, "(%s) %s (%s)",
1977 			 left, op, right);
1978 		break;
1979 
1980 	case FILTER_OP_NOT:
1981 		op = "!";
1982 		right = arg_to_str(filter, arg->op.right);
1983 		if (!right)
1984 			break;
1985 
1986 		/* See if we can consolidate */
1987 		if (strcmp(right, "TRUE") == 0)
1988 			right_val = 1;
1989 		else if (strcmp(right, "FALSE") == 0)
1990 			right_val = 0;
1991 		if (right_val >= 0) {
1992 			/* just return the opposite */
1993 			str = malloc_or_die(6);
1994 			if (right_val)
1995 				strcpy(str, "FALSE");
1996 			else
1997 				strcpy(str, "TRUE");
1998 			break;
1999 		}
2000 		len = strlen(right) + strlen(op) + 3;
2001 		str = malloc_or_die(len);
2002 		snprintf(str, len, "%s(%s)", op, right);
2003 		break;
2004 
2005 	default:
2006 		/* ?? */
2007 		break;
2008 	}
2009 	free(left);
2010 	free(right);
2011 	return str;
2012 }
2013 
val_to_str(struct event_filter * filter,struct filter_arg * arg)2014 static char *val_to_str(struct event_filter *filter, struct filter_arg *arg)
2015 {
2016 	char *str;
2017 
2018 	str = malloc_or_die(30);
2019 
2020 	snprintf(str, 30, "%lld", arg->value.val);
2021 
2022 	return str;
2023 }
2024 
field_to_str(struct event_filter * filter,struct filter_arg * arg)2025 static char *field_to_str(struct event_filter *filter, struct filter_arg *arg)
2026 {
2027 	return strdup(arg->field.field->name);
2028 }
2029 
exp_to_str(struct event_filter * filter,struct filter_arg * arg)2030 static char *exp_to_str(struct event_filter *filter, struct filter_arg *arg)
2031 {
2032 	char *lstr;
2033 	char *rstr;
2034 	char *op;
2035 	char *str = NULL;
2036 	int len;
2037 
2038 	lstr = arg_to_str(filter, arg->exp.left);
2039 	rstr = arg_to_str(filter, arg->exp.right);
2040 	if (!lstr || !rstr)
2041 		goto out;
2042 
2043 	switch (arg->exp.type) {
2044 	case FILTER_EXP_ADD:
2045 		op = "+";
2046 		break;
2047 	case FILTER_EXP_SUB:
2048 		op = "-";
2049 		break;
2050 	case FILTER_EXP_MUL:
2051 		op = "*";
2052 		break;
2053 	case FILTER_EXP_DIV:
2054 		op = "/";
2055 		break;
2056 	case FILTER_EXP_MOD:
2057 		op = "%";
2058 		break;
2059 	case FILTER_EXP_RSHIFT:
2060 		op = ">>";
2061 		break;
2062 	case FILTER_EXP_LSHIFT:
2063 		op = "<<";
2064 		break;
2065 	case FILTER_EXP_AND:
2066 		op = "&";
2067 		break;
2068 	case FILTER_EXP_OR:
2069 		op = "|";
2070 		break;
2071 	case FILTER_EXP_XOR:
2072 		op = "^";
2073 		break;
2074 	default:
2075 		die("oops in exp");
2076 	}
2077 
2078 	len = strlen(op) + strlen(lstr) + strlen(rstr) + 4;
2079 	str = malloc_or_die(len);
2080 	snprintf(str, len, "%s %s %s", lstr, op, rstr);
2081 out:
2082 	free(lstr);
2083 	free(rstr);
2084 
2085 	return str;
2086 }
2087 
num_to_str(struct event_filter * filter,struct filter_arg * arg)2088 static char *num_to_str(struct event_filter *filter, struct filter_arg *arg)
2089 {
2090 	char *lstr;
2091 	char *rstr;
2092 	char *str = NULL;
2093 	char *op = NULL;
2094 	int len;
2095 
2096 	lstr = arg_to_str(filter, arg->num.left);
2097 	rstr = arg_to_str(filter, arg->num.right);
2098 	if (!lstr || !rstr)
2099 		goto out;
2100 
2101 	switch (arg->num.type) {
2102 	case FILTER_CMP_EQ:
2103 		op = "==";
2104 		/* fall through */
2105 	case FILTER_CMP_NE:
2106 		if (!op)
2107 			op = "!=";
2108 		/* fall through */
2109 	case FILTER_CMP_GT:
2110 		if (!op)
2111 			op = ">";
2112 		/* fall through */
2113 	case FILTER_CMP_LT:
2114 		if (!op)
2115 			op = "<";
2116 		/* fall through */
2117 	case FILTER_CMP_GE:
2118 		if (!op)
2119 			op = ">=";
2120 		/* fall through */
2121 	case FILTER_CMP_LE:
2122 		if (!op)
2123 			op = "<=";
2124 
2125 		len = strlen(lstr) + strlen(op) + strlen(rstr) + 4;
2126 		str = malloc_or_die(len);
2127 		sprintf(str, "%s %s %s", lstr, op, rstr);
2128 
2129 		break;
2130 
2131 	default:
2132 		/* ?? */
2133 		break;
2134 	}
2135 
2136 out:
2137 	free(lstr);
2138 	free(rstr);
2139 	return str;
2140 }
2141 
str_to_str(struct event_filter * filter,struct filter_arg * arg)2142 static char *str_to_str(struct event_filter *filter, struct filter_arg *arg)
2143 {
2144 	char *str = NULL;
2145 	char *op = NULL;
2146 	int len;
2147 
2148 	switch (arg->str.type) {
2149 	case FILTER_CMP_MATCH:
2150 		op = "==";
2151 		/* fall through */
2152 	case FILTER_CMP_NOT_MATCH:
2153 		if (!op)
2154 			op = "!=";
2155 		/* fall through */
2156 	case FILTER_CMP_REGEX:
2157 		if (!op)
2158 			op = "=~";
2159 		/* fall through */
2160 	case FILTER_CMP_NOT_REGEX:
2161 		if (!op)
2162 			op = "!~";
2163 
2164 		len = strlen(arg->str.field->name) + strlen(op) +
2165 			strlen(arg->str.val) + 6;
2166 		str = malloc_or_die(len);
2167 		snprintf(str, len, "%s %s \"%s\"",
2168 			 arg->str.field->name,
2169 			 op, arg->str.val);
2170 		break;
2171 
2172 	default:
2173 		/* ?? */
2174 		break;
2175 	}
2176 	return str;
2177 }
2178 
arg_to_str(struct event_filter * filter,struct filter_arg * arg)2179 static char *arg_to_str(struct event_filter *filter, struct filter_arg *arg)
2180 {
2181 	char *str;
2182 
2183 	switch (arg->type) {
2184 	case FILTER_ARG_BOOLEAN:
2185 		str = malloc_or_die(6);
2186 		if (arg->boolean.value)
2187 			strcpy(str, "TRUE");
2188 		else
2189 			strcpy(str, "FALSE");
2190 		return str;
2191 
2192 	case FILTER_ARG_OP:
2193 		return op_to_str(filter, arg);
2194 
2195 	case FILTER_ARG_NUM:
2196 		return num_to_str(filter, arg);
2197 
2198 	case FILTER_ARG_STR:
2199 		return str_to_str(filter, arg);
2200 
2201 	case FILTER_ARG_VALUE:
2202 		return val_to_str(filter, arg);
2203 
2204 	case FILTER_ARG_FIELD:
2205 		return field_to_str(filter, arg);
2206 
2207 	case FILTER_ARG_EXP:
2208 		return exp_to_str(filter, arg);
2209 
2210 	default:
2211 		/* ?? */
2212 		return NULL;
2213 	}
2214 
2215 }
2216 
2217 /**
2218  * pevent_filter_make_string - return a string showing the filter
2219  * @filter: filter struct with filter information
2220  * @event_id: the event id to return the filter string with
2221  *
2222  * Returns a string that displays the filter contents.
2223  *  This string must be freed with free(str).
2224  *  NULL is returned if no filter is found.
2225  */
2226 char *
pevent_filter_make_string(struct event_filter * filter,int event_id)2227 pevent_filter_make_string(struct event_filter *filter, int event_id)
2228 {
2229 	struct filter_type *filter_type;
2230 
2231 	if (!filter->filters)
2232 		return NULL;
2233 
2234 	filter_type = find_filter_type(filter, event_id);
2235 
2236 	if (!filter_type)
2237 		return NULL;
2238 
2239 	return arg_to_str(filter, filter_type->filter);
2240 }
2241 
2242 /**
2243  * pevent_filter_compare - compare two filters and return if they are the same
2244  * @filter1: Filter to compare with @filter2
2245  * @filter2: Filter to compare with @filter1
2246  *
2247  * Returns:
2248  *  1 if the two filters hold the same content.
2249  *  0 if they do not.
2250  */
pevent_filter_compare(struct event_filter * filter1,struct event_filter * filter2)2251 int pevent_filter_compare(struct event_filter *filter1, struct event_filter *filter2)
2252 {
2253 	struct filter_type *filter_type1;
2254 	struct filter_type *filter_type2;
2255 	char *str1, *str2;
2256 	int result;
2257 	int i;
2258 
2259 	/* Do the easy checks first */
2260 	if (filter1->filters != filter2->filters)
2261 		return 0;
2262 	if (!filter1->filters && !filter2->filters)
2263 		return 1;
2264 
2265 	/*
2266 	 * Now take a look at each of the events to see if they have the same
2267 	 * filters to them.
2268 	 */
2269 	for (i = 0; i < filter1->filters; i++) {
2270 		filter_type1 = &filter1->event_filters[i];
2271 		filter_type2 = find_filter_type(filter2, filter_type1->event_id);
2272 		if (!filter_type2)
2273 			break;
2274 		if (filter_type1->filter->type != filter_type2->filter->type)
2275 			break;
2276 		switch (filter_type1->filter->type) {
2277 		case FILTER_TRIVIAL_FALSE:
2278 		case FILTER_TRIVIAL_TRUE:
2279 			/* trivial types just need the type compared */
2280 			continue;
2281 		default:
2282 			break;
2283 		}
2284 		/* The best way to compare complex filters is with strings */
2285 		str1 = arg_to_str(filter1, filter_type1->filter);
2286 		str2 = arg_to_str(filter2, filter_type2->filter);
2287 		if (str1 && str2)
2288 			result = strcmp(str1, str2) != 0;
2289 		else
2290 			/* bail out if allocation fails */
2291 			result = 1;
2292 
2293 		free(str1);
2294 		free(str2);
2295 		if (result)
2296 			break;
2297 	}
2298 
2299 	if (i < filter1->filters)
2300 		return 0;
2301 	return 1;
2302 }
2303 
2304