ltt/branches/poly/lttv/lttv/filter.h

   1 /* This file is part of the Linux Trace Toolkit viewer
   2  * Copyright (C) 2003-2004 Michel Dagenais
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License Version 2 as
   6  * published by the Free Software Foundation;
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  16  * MA 02111-1307, USA.
  17  */
  18
  19 #ifndef FILTER_H
  20 #define FILTER_H
  21
  22 #include <lttv/traceset.h>
  23
  24 /* A filter expression consists in nested AND, OR and NOT expressions
  25    involving boolean relation (>, >=, =, !=, <, <=) between event fields and
  26    specific values. It is compiled into an efficient data structure which
  27    is used in functions to check if a given event or tracefile satisfies the
  28    filter.
  29
  30    The grammar for filters is:
  31
  32    filter = expression
  33
  34    expression = "(" expression ")" | "!" expression |
  35                 expression "&&" expression | expression "||" expression |
  36                 simpleExpression
  37
  38    simpleExpression = fieldPath op value
  39
  40    fieldPath = fieldComponent [ "." fieldPath ]
  41
  42    fieldComponent = name [ "[" integer "]" ]
  43
  44    value = integer | double | string
  45
  46 */
  47
  48 /**
  49  * @struct lttv_filter
  50  * ( will later contain a binary tree of filtering options )
  51  */
  52 typedef struct _lttv_filter lttv_filter;
  53
  54 /* Compile the filter expression into an efficient data structure */
  55
  56 lttv_filter *lttv_filter_new(char *expression, LttvTrace *t);
  57
  58
  59 /* Check if the tracefile or event satisfies the filter. The arguments are
  60    declared as void * to allow these functions to be used as hooks. */
  61
  62 gboolean lttv_filter_tracefile(lttv_filter *filter, void *tracefile);
  63
  64 gboolean lttv_filter_event(lttv_filter *filter, void *event);
  65
  66 #endif // FILTER_H
  67