Commit 68baa431 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Arnaldo Carvalho de Melo
Browse files

perf tools: Add strfilter for general purpose string filter 



Add strfilter for general purpose string filter.

Every filter rules are descrived by glob matching pattern and '!' prefix
which means Logical NOT.

A strfilter consists of those filter rules connected with '&' and '|'.

A set of rules can be folded by using '(' and ')'.

It also accepts spaces around rules and those operators.

Format:
<rule> ::= <glob-exp> | "!" <rule> | <rule> <op> <rule> | "(" <rule> ")"
<op> ::= "&" | "|"

e.g.:

 "(add* | del*) & *timer" filter rules pass strings which start with add
 or del and end with timer.

This will be used by perf probe --filter.

Changes in V2:
 - Fix to check result of strdup() and strfilter__alloc().
 - Encapsulate and simplify interfaces as like regex(3).

Cc: 2nddept-manager@sdl.hitachi.co.jp
Cc: Franck Bui-Huu <fbuihuu@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20110120141530.25915.12673.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: default avatarMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent d380eaae

tools/perf/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -417,6 +417,7 @@ LIB_H += util/help.h 
LIB_H += util/session.h

LIB_H += util/strbuf.h

LIB_H += util/strlist.h

LIB_H += util/strfilter.h

LIB_H += util/svghelper.h

LIB_H += util/run-command.h

LIB_H += util/sigchain.h
@@ -458,6 +459,7 @@ LIB_OBJS += $(OUTPUT)util/quote.o 
LIB_OBJS += $(OUTPUT)util/strbuf.o

LIB_OBJS += $(OUTPUT)util/string.o

LIB_OBJS += $(OUTPUT)util/strlist.o

LIB_OBJS += $(OUTPUT)util/strfilter.o

LIB_OBJS += $(OUTPUT)util/usage.o

LIB_OBJS += $(OUTPUT)util/wrapper.o

LIB_OBJS += $(OUTPUT)util/sigchain.o

tools/perf/util/strfilter.c

0 → 100644
+200 −0
Original line number Diff line number Diff line 
#include <ctype.h>

#include "util.h"

#include "string.h"

#include "strfilter.h"



/* Operators */

static const char *OP_and	= "&";	/* Logical AND */

static const char *OP_or	= "|";	/* Logical OR */

static const char *OP_not	= "!";	/* Logical NOT */



#define is_operator(c)	((c) == '|' || (c) == '&' || (c) == '!')

#define is_separator(c)	(is_operator(c) || (c) == '(' || (c) == ')')



static void strfilter_node__delete(struct strfilter_node *self)

{

	if (self) {

		if (self->p && !is_operator(*self->p))

			free((char *)self->p);

		strfilter_node__delete(self->l);

		strfilter_node__delete(self->r);

		free(self);

	}

}



void strfilter__delete(struct strfilter *self)

{

	if (self) {

		strfilter_node__delete(self->root);

		free(self);

	}

}



static const char *get_token(const char *s, const char **e)

{

	const char *p;



	while (isspace(*s))	/* Skip spaces */

		s++;



	if (*s == '\0') {

		p = s;

		goto end;

	}



	p = s + 1;

	if (!is_separator(*s)) {

		/* End search */

retry:

		while (*p && !is_separator(*p) && !isspace(*p))

			p++;

		/* Escape and special case: '!' is also used in glob pattern */

		if (*(p - 1) == '\\' || (*p == '!' && *(p - 1) == '[')) {

			p++;

			goto retry;

		}

	}

end:

	*e = p;

	return s;

}



static struct strfilter_node *strfilter_node__alloc(const char *op,

						    struct strfilter_node *l,

						    struct strfilter_node *r)

{

	struct strfilter_node *ret = zalloc(sizeof(struct strfilter_node));



	if (ret) {

		ret->p = op;

		ret->l = l;

		ret->r = r;

	}



	return ret;

}



static struct strfilter_node *strfilter_node__new(const char *s,

						  const char **ep)

{

	struct strfilter_node root, *cur, *last_op;

	const char *e;



	if (!s)

		return NULL;



	memset(&root, 0, sizeof(root));

	last_op = cur = &root;



	s = get_token(s, &e);

	while (*s != '\0' && *s != ')') {

		switch (*s) {

		case '&':	/* Exchg last OP->r with AND */

			if (!cur->r || !last_op->r)

				goto error;

			cur = strfilter_node__alloc(OP_and, last_op->r, NULL);

			if (!cur)

				goto nomem;

			last_op->r = cur;

			last_op = cur;

			break;

		case '|':	/* Exchg the root with OR */

			if (!cur->r || !root.r)

				goto error;

			cur = strfilter_node__alloc(OP_or, root.r, NULL);

			if (!cur)

				goto nomem;

			root.r = cur;

			last_op = cur;

			break;

		case '!':	/* Add NOT as a leaf node */

			if (cur->r)

				goto error;

			cur->r = strfilter_node__alloc(OP_not, NULL, NULL);

			if (!cur->r)

				goto nomem;

			cur = cur->r;

			break;

		case '(':	/* Recursively parses inside the parenthesis */

			if (cur->r)

				goto error;

			cur->r = strfilter_node__new(s + 1, &s);

			if (!s)

				goto nomem;

			if (!cur->r || *s != ')')

				goto error;

			e = s + 1;

			break;

		default:

			if (cur->r)

				goto error;

			cur->r = strfilter_node__alloc(NULL, NULL, NULL);

			if (!cur->r)

				goto nomem;

			cur->r->p = strndup(s, e - s);

			if (!cur->r->p)

				goto nomem;

		}

		s = get_token(e, &e);

	}

	if (!cur->r)

		goto error;

	*ep = s;

	return root.r;

nomem:

	s = NULL;

error:

	*ep = s;

	strfilter_node__delete(root.r);

	return NULL;

}



/*

 * Parse filter rule and return new strfilter.

 * Return NULL if fail, and *ep == NULL if memory allocation failed.

 */

struct strfilter *strfilter__new(const char *rules, const char **err)

{

	struct strfilter *ret = zalloc(sizeof(struct strfilter));

	const char *ep = NULL;



	if (ret)

		ret->root = strfilter_node__new(rules, &ep);



	if (!ret || !ret->root || *ep != '\0') {

		if (err)

			*err = ep;

		strfilter__delete(ret);

		ret = NULL;

	}



	return ret;

}



static bool strfilter_node__compare(struct strfilter_node *self,

				    const char *str)

{

	if (!self || !self->p)

		return false;



	switch (*self->p) {

	case '|':	/* OR */

		return strfilter_node__compare(self->l, str) ||

			strfilter_node__compare(self->r, str);

	case '&':	/* AND */

		return strfilter_node__compare(self->l, str) &&

			strfilter_node__compare(self->r, str);

	case '!':	/* NOT */

		return !strfilter_node__compare(self->r, str);

	default:

		return strglobmatch(str, self->p);

	}

}



/* Return true if STR matches the filter rules */

bool strfilter__compare(struct strfilter *self, const char *str)

{

	if (!self)

		return false;

	return strfilter_node__compare(self->root, str);

}

tools/perf/util/strfilter.h

0 → 100644
+48 −0
Original line number Diff line number Diff line 
#ifndef __PERF_STRFILTER_H

#define __PERF_STRFILTER_H

/* General purpose glob matching filter */



#include <linux/list.h>

#include <stdbool.h>



/* A node of string filter */

struct strfilter_node {

	struct strfilter_node *l;	/* Tree left branche (for &,|) */

	struct strfilter_node *r;	/* Tree right branche (for !,&,|) */

	const char *p;		/* Operator or rule */

};



/* String filter */

struct strfilter {

	struct strfilter_node *root;

};



/**

 * strfilter__new - Create a new string filter

 * @rules: Filter rule, which is a combination of glob expressions.

 * @err: Pointer which points an error detected on @rules

 *

 * Parse @rules and return new strfilter. Return NULL if an error detected.

 * In that case, *@err will indicate where it is detected, and *@err is NULL

 * if a memory allocation is failed.

 */

struct strfilter *strfilter__new(const char *rules, const char **err);



/**

 * strfilter__compare - compare given string and a string filter

 * @self: String filter

 * @str: target string

 *

 * Compare @str and @self. Return true if the str match the rule

 */

bool strfilter__compare(struct strfilter *self, const char *str);



/**

 * strfilter__delete - delete a string filter

 * @self: String filter to delete

 *

 * Delete @self.

 */

void strfilter__delete(struct strfilter *self);



#endif

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