blob: 0144b3d1bb77ac63441c77e1bb24e3405cfe3d8f [file] [log] [blame]
/*
* Copyright (C) 2010 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License (not later!)
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, see <http://www.gnu.org/licenses>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <errno.h>
#include <sys/types.h>
#include "event-parse.h"
#include "event-utils.h"
#define COMM "COMM"
static struct format_field comm = {
.name = "COMM",
};
struct event_list {
struct event_list *next;
struct event_format *event;
};
static void show_error(char *error_buf, const char *fmt, ...)
{
unsigned long long index;
const char *input;
va_list ap;
int len;
int i;
input = pevent_get_input_buf();
index = pevent_get_input_buf_ptr();
len = input ? strlen(input) : 0;
if (len) {
strcpy(error_buf, input);
error_buf[len] = '\n';
for (i = 1; i < len && i < index; i++)
error_buf[len+i] = ' ';
error_buf[len + i] = '^';
error_buf[len + i + 1] = '\n';
len += i+2;
}
va_start(ap, fmt);
vsnprintf(error_buf + len, PEVENT_FILTER_ERROR_BUFSZ - len, fmt, ap);
va_end(ap);
}
static void free_token(char *token)
{
pevent_free_token(token);
}
static enum event_type read_token(char **tok)
{
enum event_type type;
char *token = NULL;
do {
free_token(token);
type = pevent_read_token(&token);
} while (type == EVENT_NEWLINE || type == EVENT_SPACE);
/* If token is = or ! check to see if the next char is ~ */
if (token &&
(strcmp(token, "=") == 0 || strcmp(token, "!") == 0) &&
pevent_peek_char() == '~') {
/* append it */
*tok = malloc(3);
if (*tok == NULL) {
free_token(token);
return EVENT_ERROR;
}
sprintf(*tok, "%c%c", *token, '~');
free_token(token);
/* Now remove the '~' from the buffer */
pevent_read_token(&token);
free_token(token);
} else
*tok = token;
return type;
}
static int filter_cmp(const void *a, const void *b)
{
const struct filter_type *ea = a;
const struct filter_type *eb = b;
if (ea->event_id < eb->event_id)
return -1;
if (ea->event_id > eb->event_id)
return 1;
return 0;
}
static struct filter_type *
find_filter_type(struct event_filter *filter, int id)
{
struct filter_type *filter_type;
struct filter_type key;
key.event_id = id;
filter_type = bsearch(&key, filter->event_filters,
filter->filters,
sizeof(*filter->event_filters),
filter_cmp);
return filter_type;
}
static struct filter_type *
add_filter_type(struct event_filter *filter, int id)
{
struct filter_type *filter_type;
int i;
filter_type = find_filter_type(filter, id);
if (filter_type)
return filter_type;
filter_type = realloc(filter->event_filters,
sizeof(*filter->event_filters) *
(filter->filters + 1));
if (!filter_type)
return NULL;
filter->event_filters = filter_type;
for (i = 0; i < filter->filters; i++) {
if (filter->event_filters[i].event_id > id)
break;
}
if (i < filter->filters)
memmove(&filter->event_filters[i+1],
&filter->event_filters[i],
sizeof(*filter->event_filters) *
(filter->filters - i));
filter_type = &filter->event_filters[i];
filter_type->event_id = id;
filter_type->event = pevent_find_event(filter->pevent, id);
filter_type->filter = NULL;
filter->filters++;
return filter_type;
}
/**
* pevent_filter_alloc - create a new event filter
* @pevent: The pevent that this filter is associated with
*/
struct event_filter *pevent_filter_alloc(struct pevent *pevent)
{
struct event_filter *filter;
filter = malloc(sizeof(*filter));
if (filter == NULL)
return NULL;
memset(filter, 0, sizeof(*filter));
filter->pevent = pevent;
pevent_ref(pevent);
return filter;
}
static struct filter_arg *allocate_arg(void)
{
return calloc(1, sizeof(struct filter_arg));
}
static void free_arg(struct filter_arg *arg)
{
if (!arg)
return;
switch (arg->type) {
case FILTER_ARG_NONE:
case FILTER_ARG_BOOLEAN:
break;
case FILTER_ARG_NUM:
free_arg(arg->num.left);
free_arg(arg->num.right);
break;
case FILTER_ARG_EXP:
free_arg(arg->exp.left);
free_arg(arg->exp.right);
break;
case FILTER_ARG_STR:
free(arg->str.val);
regfree(&arg->str.reg);
free(arg->str.buffer);
break;
case FILTER_ARG_VALUE:
if (arg->value.type == FILTER_STRING ||
arg->value.type == FILTER_CHAR)
free(arg->value.str);
break;
case FILTER_ARG_OP:
free_arg(arg->op.left);
free_arg(arg->op.right);
default:
break;
}
free(arg);
}
static int add_event(struct event_list **events,
struct event_format *event)
{
struct event_list *list;
list = malloc(sizeof(*list));
if (list == NULL)
return -1;
list->next = *events;
*events = list;
list->event = event;
return 0;
}
static int event_match(struct event_format *event,
regex_t *sreg, regex_t *ereg)
{
if (sreg) {
return !regexec(sreg, event->system, 0, NULL, 0) &&
!regexec(ereg, event->name, 0, NULL, 0);
}
return !regexec(ereg, event->system, 0, NULL, 0) ||
!regexec(ereg, event->name, 0, NULL, 0);
}
static enum pevent_errno
find_event(struct pevent *pevent, struct event_list **events,
char *sys_name, char *event_name)
{
struct event_format *event;
regex_t ereg;
regex_t sreg;
int match = 0;
int fail = 0;
char *reg;
int ret;
int i;
if (!event_name) {
/* if no name is given, then swap sys and name */
event_name = sys_name;
sys_name = NULL;
}
reg = malloc(strlen(event_name) + 3);
if (reg == NULL)
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
sprintf(reg, "^%s$", event_name);
ret = regcomp(&ereg, reg, REG_ICASE|REG_NOSUB);
free(reg);
if (ret)
return PEVENT_ERRNO__INVALID_EVENT_NAME;
if (sys_name) {
reg = malloc(strlen(sys_name) + 3);
if (reg == NULL) {
regfree(&ereg);
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
}
sprintf(reg, "^%s$", sys_name);
ret = regcomp(&sreg, reg, REG_ICASE|REG_NOSUB);
free(reg);
if (ret) {
regfree(&ereg);
return PEVENT_ERRNO__INVALID_EVENT_NAME;
}
}
for (i = 0; i < pevent->nr_events; i++) {
event = pevent->events[i];
if (event_match(event, sys_name ? &sreg : NULL, &ereg)) {
match = 1;
if (add_event(events, event) < 0) {
fail = 1;
break;
}
}
}
regfree(&ereg);
if (sys_name)
regfree(&sreg);
if (!match)
return PEVENT_ERRNO__EVENT_NOT_FOUND;
if (fail)
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
return 0;
}
static void free_events(struct event_list *events)
{
struct event_list *event;
while (events) {
event = events;
events = events->next;
free(event);
}
}
static enum pevent_errno
create_arg_item(struct event_format *event, const char *token,
enum event_type type, struct filter_arg **parg, char *error_str)
{
struct format_field *field;
struct filter_arg *arg;
arg = allocate_arg();
if (arg == NULL) {
show_error(error_str, "failed to allocate filter arg");
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
}
switch (type) {
case EVENT_SQUOTE:
case EVENT_DQUOTE:
arg->type = FILTER_ARG_VALUE;
arg->value.type =
type == EVENT_DQUOTE ? FILTER_STRING : FILTER_CHAR;
arg->value.str = strdup(token);
if (!arg->value.str) {
free_arg(arg);
show_error(error_str, "failed to allocate string filter arg");
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
}
break;
case EVENT_ITEM:
/* if it is a number, then convert it */
if (isdigit(token[0])) {
arg->type = FILTER_ARG_VALUE;
arg->value.type = FILTER_NUMBER;
arg->value.val = strtoull(token, NULL, 0);
break;
}
/* Consider this a field */
field = pevent_find_any_field(event, token);
if (!field) {
if (strcmp(token, COMM) != 0) {
/* not a field, Make it false */
arg->type = FILTER_ARG_BOOLEAN;
arg->boolean.value = FILTER_FALSE;
break;
}
/* If token is 'COMM' then it is special */
field = &comm;
}
arg->type = FILTER_ARG_FIELD;
arg->field.field = field;
break;
default:
free_arg(arg);
show_error(error_str, "expected a value but found %s", token);
return PEVENT_ERRNO__UNEXPECTED_TYPE;
}
*parg = arg;
return 0;
}
static struct filter_arg *
create_arg_op(enum filter_op_type btype)
{
struct filter_arg *arg;
arg = allocate_arg();
if (!arg)
return NULL;
arg->type = FILTER_ARG_OP;
arg->op.type = btype;
return arg;
}
static struct filter_arg *
create_arg_exp(enum filter_exp_type etype)
{
struct filter_arg *arg;
arg = allocate_arg();
if (!arg)
return NULL;
arg->type = FILTER_ARG_EXP;
arg->op.type = etype;
return arg;
}
static struct filter_arg *
create_arg_cmp(enum filter_exp_type etype)
{
struct filter_arg *arg;
arg = allocate_arg();
if (!arg)
return NULL;
/* Use NUM and change if necessary */
arg->type = FILTER_ARG_NUM;
arg->op.type = etype;
return arg;
}
static enum pevent_errno
add_right(struct filter_arg *op, struct filter_arg *arg, char *error_str)
{
struct filter_arg *left;
char *str;
int op_type;
int ret;
switch (op->type) {
case FILTER_ARG_EXP:
if (op->exp.right)
goto out_fail;
op->exp.right = arg;
break;
case FILTER_ARG_OP:
if (op->op.right)
goto out_fail;
op->op.right = arg;
break;
case FILTER_ARG_NUM:
if (op->op.right)
goto out_fail;
/*
* The arg must be num, str, or field
*/
switch (arg->type) {
case FILTER_ARG_VALUE:
case FILTER_ARG_FIELD:
break;
default:
show_error(error_str, "Illegal rvalue");
return PEVENT_ERRNO__ILLEGAL_RVALUE;
}
/*
* Depending on the type, we may need to
* convert this to a string or regex.
*/
switch (arg->value.type) {
case FILTER_CHAR:
/*
* A char should be converted to number if
* the string is 1 byte, and the compare
* is not a REGEX.
*/
if (strlen(arg->value.str) == 1 &&
op->num.type != FILTER_CMP_REGEX &&
op->num.type != FILTER_CMP_NOT_REGEX) {
arg->value.type = FILTER_NUMBER;
goto do_int;
}
/* fall through */
case FILTER_STRING:
/* convert op to a string arg */
op_type = op->num.type;
left = op->num.left;
str = arg->value.str;
/* reset the op for the new field */
memset(op, 0, sizeof(*op));
/*
* If left arg was a field not found then
* NULL the entire op.
*/
if (left->type == FILTER_ARG_BOOLEAN) {
free_arg(left);
free_arg(arg);
op->type = FILTER_ARG_BOOLEAN;
op->boolean.value = FILTER_FALSE;
break;
}
/* Left arg must be a field */
if (left->type != FILTER_ARG_FIELD) {
show_error(error_str,
"Illegal lvalue for string comparison");
return PEVENT_ERRNO__ILLEGAL_LVALUE;
}
/* Make sure this is a valid string compare */
switch (op_type) {
case FILTER_CMP_EQ:
op_type = FILTER_CMP_MATCH;
break;
case FILTER_CMP_NE:
op_type = FILTER_CMP_NOT_MATCH;
break;
case FILTER_CMP_REGEX:
case FILTER_CMP_NOT_REGEX:
ret = regcomp(&op->str.reg, str, REG_ICASE|REG_NOSUB);
if (ret) {
show_error(error_str,
"RegEx '%s' did not compute",
str);
return PEVENT_ERRNO__INVALID_REGEX;
}
break;
default:
show_error(error_str,
"Illegal comparison for string");
return PEVENT_ERRNO__ILLEGAL_STRING_CMP;
}
op->type = FILTER_ARG_STR;
op->str.type = op_type;
op->str.field = left->field.field;
op->str.val = strdup(str);
if (!op->str.val) {
show_error(error_str, "Failed to allocate string filter");
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
}
/*
* Need a buffer to copy data for tests
*/
op->str.buffer = malloc(op->str.field->size + 1);
if (!op->str.buffer) {
show_error(error_str, "Failed to allocate string filter");
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
}
/* Null terminate this buffer */
op->str.buffer[op->str.field->size] = 0;
/* We no longer have left or right args */
free_arg(arg);
free_arg(left);
break;
case FILTER_NUMBER:
do_int:
switch (op->num.type) {
case FILTER_CMP_REGEX:
case FILTER_CMP_NOT_REGEX:
show_error(error_str,
"Op not allowed with integers");
return PEVENT_ERRNO__ILLEGAL_INTEGER_CMP;
default:
break;
}
/* numeric compare */
op->num.right = arg;
break;
default:
goto out_fail;
}
break;
default:
goto out_fail;
}
return 0;
out_fail:
show_error(error_str, "Syntax error");
return PEVENT_ERRNO__SYNTAX_ERROR;
}
static struct filter_arg *
rotate_op_right(struct filter_arg *a, struct filter_arg *b)
{
struct filter_arg *arg;
arg = a->op.right;
a->op.right = b;
return arg;
}
static enum pevent_errno add_left(struct filter_arg *op, struct filter_arg *arg)
{
switch (op->type) {
case FILTER_ARG_EXP:
if (arg->type == FILTER_ARG_OP)
arg = rotate_op_right(arg, op);
op->exp.left = arg;
break;
case FILTER_ARG_OP:
op->op.left = arg;
break;
case FILTER_ARG_NUM:
if (arg->type == FILTER_ARG_OP)
arg = rotate_op_right(arg, op);
/* left arg of compares must be a field */
if (arg->type != FILTER_ARG_FIELD &&
arg->type != FILTER_ARG_BOOLEAN)
return PEVENT_ERRNO__INVALID_ARG_TYPE;
op->num.left = arg;
break;
default:
return PEVENT_ERRNO__INVALID_ARG_TYPE;
}
return 0;
}
enum op_type {
OP_NONE,
OP_BOOL,
OP_NOT,
OP_EXP,
OP_CMP,
};
static enum op_type process_op(const char *token,
enum filter_op_type *btype,
enum filter_cmp_type *ctype,
enum filter_exp_type *etype)
{
*btype = FILTER_OP_NOT;
*etype = FILTER_EXP_NONE;
*ctype = FILTER_CMP_NONE;
if (strcmp(token, "&&") == 0)
*btype = FILTER_OP_AND;
else if (strcmp(token, "||") == 0)
*btype = FILTER_OP_OR;
else if (strcmp(token, "!") == 0)
return OP_NOT;
if (*btype != FILTER_OP_NOT)
return OP_BOOL;
/* Check for value expressions */
if (strcmp(token, "+") == 0) {
*etype = FILTER_EXP_ADD;
} else if (strcmp(token, "-") == 0) {
*etype = FILTER_EXP_SUB;
} else if (strcmp(token, "*") == 0) {
*etype = FILTER_EXP_MUL;
} else if (strcmp(token, "/") == 0) {
*etype = FILTER_EXP_DIV;
} else if (strcmp(token, "%") == 0) {
*etype = FILTER_EXP_MOD;
} else if (strcmp(token, ">>") == 0) {
*etype = FILTER_EXP_RSHIFT;
} else if (strcmp(token, "<<") == 0) {
*etype = FILTER_EXP_LSHIFT;
} else if (strcmp(token, "&") == 0) {
*etype = FILTER_EXP_AND;
} else if (strcmp(token, "|") == 0) {
*etype = FILTER_EXP_OR;
} else if (strcmp(token, "^") == 0) {
*etype = FILTER_EXP_XOR;
} else if (strcmp(token, "~") == 0)
*etype = FILTER_EXP_NOT;
if (*etype != FILTER_EXP_NONE)
return OP_EXP;
/* Check for compares */
if (strcmp(token, "==") == 0)
*ctype = FILTER_CMP_EQ;
else if (strcmp(token, "!=") == 0)
*ctype = FILTER_CMP_NE;
else if (strcmp(token, "<") == 0)
*ctype = FILTER_CMP_LT;
else if (strcmp(token, ">") == 0)
*ctype = FILTER_CMP_GT;
else if (strcmp(token, "<=") == 0)
*ctype = FILTER_CMP_LE;
else if (strcmp(token, ">=") == 0)
*ctype = FILTER_CMP_GE;
else if (strcmp(token, "=~") == 0)
*ctype = FILTER_CMP_REGEX;
else if (strcmp(token, "!~") == 0)
*ctype = FILTER_CMP_NOT_REGEX;
else
return OP_NONE;
return OP_CMP;
}
static int check_op_done(struct filter_arg *arg)
{
switch (arg->type) {
case FILTER_ARG_EXP:
return arg->exp.right != NULL;
case FILTER_ARG_OP:
return arg->op.right != NULL;
case FILTER_ARG_NUM:
return arg->num.right != NULL;
case FILTER_ARG_STR:
/* A string conversion is always done */
return 1;
case FILTER_ARG_BOOLEAN:
/* field not found, is ok */
return 1;
default:
return 0;
}
}
enum filter_vals {
FILTER_VAL_NORM,
FILTER_VAL_FALSE,
FILTER_VAL_TRUE,
};
static enum pevent_errno
reparent_op_arg(struct filter_arg *parent, struct filter_arg *old_child,
struct filter_arg *arg, char *error_str)
{
struct filter_arg *other_child;
struct filter_arg **ptr;
if (parent->type != FILTER_ARG_OP &&
arg->type != FILTER_ARG_OP) {
show_error(error_str, "can not reparent other than OP");
return PEVENT_ERRNO__REPARENT_NOT_OP;
}
/* Get the sibling */
if (old_child->op.right == arg) {
ptr = &old_child->op.right;
other_child = old_child->op.left;
} else if (old_child->op.left == arg) {
ptr = &old_child->op.left;
other_child = old_child->op.right;
} else {
show_error(error_str, "Error in reparent op, find other child");
return PEVENT_ERRNO__REPARENT_FAILED;
}
/* Detach arg from old_child */
*ptr = NULL;
/* Check for root */
if (parent == old_child) {
free_arg(other_child);
*parent = *arg;
/* Free arg without recussion */
free(arg);
return 0;
}
if (parent->op.right == old_child)
ptr = &parent->op.right;
else if (parent->op.left == old_child)
ptr = &parent->op.left;
else {
show_error(error_str, "Error in reparent op");
return PEVENT_ERRNO__REPARENT_FAILED;
}
*ptr = arg;
free_arg(old_child);
return 0;
}
/* Returns either filter_vals (success) or pevent_errno (failfure) */
static int test_arg(struct filter_arg *parent, struct filter_arg *arg,
char *error_str)
{
int lval, rval;
switch (arg->type) {
/* bad case */
case FILTER_ARG_BOOLEAN:
return FILTER_VAL_FALSE + arg->boolean.value;
/* good cases: */
case FILTER_ARG_STR:
case FILTER_ARG_VALUE:
case FILTER_ARG_FIELD:
return FILTER_VAL_NORM;
case FILTER_ARG_EXP:
lval = test_arg(arg, arg->exp.left, error_str);
if (lval != FILTER_VAL_NORM)
return lval;
rval = test_arg(arg, arg->exp.right, error_str);
if (rval != FILTER_VAL_NORM)
return rval;
return FILTER_VAL_NORM;
case FILTER_ARG_NUM:
lval = test_arg(arg, arg->num.left, error_str);
if (lval != FILTER_VAL_NORM)
return lval;
rval = test_arg(arg, arg->num.right, error_str);
if (rval != FILTER_VAL_NORM)
return rval;
return FILTER_VAL_NORM;
case FILTER_ARG_OP:
if (arg->op.type != FILTER_OP_NOT) {
lval = test_arg(arg, arg->op.left, error_str);
switch (lval) {
case FILTER_VAL_NORM:
break;
case FILTER_VAL_TRUE:
if (arg->op.type == FILTER_OP_OR)
return FILTER_VAL_TRUE;
rval = test_arg(arg, arg->op.right, error_str);
if (rval != FILTER_VAL_NORM)
return rval;
return reparent_op_arg(parent, arg, arg->op.right,
error_str);
case FILTER_VAL_FALSE:
if (arg->op.type == FILTER_OP_AND)
return FILTER_VAL_FALSE;
rval = test_arg(arg, arg->op.right, error_str);
if (rval != FILTER_VAL_NORM)
return rval;
return reparent_op_arg(parent, arg, arg->op.right,
error_str);
default:
return lval;
}
}
rval = test_arg(arg, arg->op.right, error_str);
switch (rval) {
case FILTER_VAL_NORM:
default:
break;
case FILTER_VAL_TRUE:
if (arg->op.type == FILTER_OP_OR)
return FILTER_VAL_TRUE;
if (arg->op.type == FILTER_OP_NOT)
return FILTER_VAL_FALSE;
return reparent_op_arg(parent, arg, arg->op.left,
error_str);
case FILTER_VAL_FALSE:
if (arg->op.type == FILTER_OP_AND)
return FILTER_VAL_FALSE;
if (arg->op.type == FILTER_OP_NOT)
return FILTER_VAL_TRUE;
return reparent_op_arg(parent, arg, arg->op.left,
error_str);
}
return rval;
default:
show_error(error_str, "bad arg in filter tree");
return PEVENT_ERRNO__BAD_FILTER_ARG;
}
return FILTER_VAL_NORM;
}
/* Remove any unknown event fields */
static int collapse_tree(struct filter_arg *arg,
struct filter_arg **arg_collapsed, char *error_str)
{
int ret;
ret = test_arg(arg, arg, error_str);
switch (ret) {
case FILTER_VAL_NORM:
break;
case FILTER_VAL_TRUE:
case FILTER_VAL_FALSE:
free_arg(arg);
arg = allocate_arg();
if (arg) {
arg->type = FILTER_ARG_BOOLEAN;
arg->boolean.value = ret == FILTER_VAL_TRUE;
} else {
show_error(error_str, "Failed to allocate filter arg");
ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
}
break;
default:
/* test_arg() already set the error_str */
free_arg(arg);
arg = NULL;
break;
}
*arg_collapsed = arg;
return ret;
}
static enum pevent_errno
process_filter(struct event_format *event, struct filter_arg **parg,
char *error_str, int not)
{
enum event_type type;
char *token = NULL;
struct filter_arg *current_op = NULL;
struct filter_arg *current_exp = NULL;
struct filter_arg *left_item = NULL;
struct filter_arg *arg = NULL;
enum op_type op_type;
enum filter_op_type btype;
enum filter_exp_type etype;
enum filter_cmp_type ctype;
enum pevent_errno ret;
*parg = NULL;
do {
free(token);
type = read_token(&token);
switch (type) {
case EVENT_SQUOTE:
case EVENT_DQUOTE:
case EVENT_ITEM:
ret = create_arg_item(event, token, type, &arg, error_str);
if (ret < 0)
goto fail;
if (!left_item)
left_item = arg;
else if (current_exp) {
ret = add_right(current_exp, arg, error_str);
if (ret < 0)
goto fail;
left_item = NULL;
/* Not's only one one expression */
if (not) {
arg = NULL;
if (current_op)
goto fail_syntax;
free(token);
*parg = current_exp;
return 0;
}
} else
goto fail_syntax;
arg = NULL;
break;
case EVENT_DELIM:
if (*token == ',') {
show_error(error_str, "Illegal token ','");
ret = PEVENT_ERRNO__ILLEGAL_TOKEN;
goto fail;
}
if (*token == '(') {
if (left_item) {
show_error(error_str,
"Open paren can not come after item");
ret = PEVENT_ERRNO__INVALID_PAREN;
goto fail;
}
if (current_exp) {
show_error(error_str,
"Open paren can not come after expression");
ret = PEVENT_ERRNO__INVALID_PAREN;
goto fail;
}
ret = process_filter(event, &arg, error_str, 0);
if (ret != PEVENT_ERRNO__UNBALANCED_PAREN) {
if (ret == 0) {
show_error(error_str,
"Unbalanced number of '('");
ret = PEVENT_ERRNO__UNBALANCED_PAREN;
}
goto fail;
}
ret = 0;
/* A not wants just one expression */
if (not) {
if (current_op)
goto fail_syntax;
*parg = arg;
return 0;
}
if (current_op)
ret = add_right(current_op, arg, error_str);
else
current_exp = arg;
if (ret < 0)
goto fail;
} else { /* ')' */
if (!current_op && !current_exp)
goto fail_syntax;
/* Make sure everything is finished at this level */
if (current_exp && !check_op_done(current_exp))
goto fail_syntax;
if (current_op && !check_op_done(current_op))
goto fail_syntax;
if (current_op)
*parg = current_op;
else
*parg = current_exp;
free(token);
return PEVENT_ERRNO__UNBALANCED_PAREN;
}
break;
case EVENT_OP:
op_type = process_op(token, &btype, &ctype, &etype);
/* All expect a left arg except for NOT */
switch (op_type) {
case OP_BOOL:
/* Logic ops need a left expression */
if (!current_exp && !current_op)
goto fail_syntax;
/* fall through */
case OP_NOT:
/* logic only processes ops and exp */
if (left_item)
goto fail_syntax;
break;
case OP_EXP:
case OP_CMP:
if (!left_item)
goto fail_syntax;
break;
case OP_NONE:
show_error(error_str,
"Unknown op token %s", token);
ret = PEVENT_ERRNO__UNKNOWN_TOKEN;
goto fail;
}
ret = 0;
switch (op_type) {
case OP_BOOL:
arg = create_arg_op(btype);
if (arg == NULL)
goto fail_alloc;
if (current_op)
ret = add_left(arg, current_op);
else
ret = add_left(arg, current_exp);
current_op = arg;
current_exp = NULL;
break;
case OP_NOT:
arg = create_arg_op(btype);
if (arg == NULL)
goto fail_alloc;
if (current_op)
ret = add_right(current_op, arg, error_str);
if (ret < 0)
goto fail;
current_exp = arg;
ret = process_filter(event, &arg, error_str, 1);
if (ret < 0)
goto fail;
ret = add_right(current_exp, arg, error_str);
if (ret < 0)
goto fail;
break;
case OP_EXP:
case OP_CMP:
if (op_type == OP_EXP)
arg = create_arg_exp(etype);
else
arg = create_arg_cmp(ctype);
if (arg == NULL)
goto fail_alloc;
if (current_op)
ret = add_right(current_op, arg, error_str);
if (ret < 0)
goto fail;
ret = add_left(arg, left_item);
if (ret < 0) {
arg = NULL;
goto fail_syntax;
}
current_exp = arg;
break;
default:
break;
}
arg = NULL;
if (ret < 0)
goto fail_syntax;
break;
case EVENT_NONE:
break;
case EVENT_ERROR:
goto fail_alloc;
default:
goto fail_syntax;
}
} while (type != EVENT_NONE);
if (!current_op && !current_exp)
goto fail_syntax;
if (!current_op)
current_op = current_exp;
ret = collapse_tree(current_op, parg, error_str);
if (ret < 0)
goto fail;
*parg = current_op;
free(token);
return 0;
fail_alloc:
show_error(error_str, "failed to allocate filter arg");
ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
goto fail;
fail_syntax:
show_error(error_str, "Syntax error");
ret = PEVENT_ERRNO__SYNTAX_ERROR;
fail:
free_arg(current_op);
free_arg(current_exp);
free_arg(arg);
free(token);
return ret;
}
static enum pevent_errno
process_event(struct event_format *event, const char *filter_str,
struct filter_arg **parg, char *error_str)
{
int ret;
pevent_buffer_init(filter_str, strlen(filter_str));
ret = process_filter(event, parg, error_str, 0);
if (ret < 0)
return ret;
/* If parg is NULL, then make it into FALSE */
if (!*parg) {
*parg = allocate_arg();
if (*parg == NULL)
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
(*parg)->type = FILTER_ARG_BOOLEAN;
(*parg)->boolean.value = FILTER_FALSE;
}
return 0;
}
static enum pevent_errno
filter_event(struct event_filter *filter, struct event_format *event,
const char *filter_str, char *error_str)
{
struct filter_type *filter_type;
struct filter_arg *arg;
enum pevent_errno ret;
if (filter_str) {
ret = process_event(event, filter_str, &arg, error_str);
if (ret < 0)
return ret;
} else {
/* just add a TRUE arg */
arg = allocate_arg();
if (arg == NULL)
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
arg->type = FILTER_ARG_BOOLEAN;
arg->boolean.value = FILTER_TRUE;
}
filter_type = add_filter_type(filter, event->id);
if (filter_type == NULL)
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
if (filter_type->filter)
free_arg(filter_type->filter);
filter_type->filter = arg;
return 0;
}
static void filter_init_error_buf(struct event_filter *filter)
{
/* clear buffer to reset show error */
pevent_buffer_init("", 0);
filter->error_buffer[0] = '\0';
}
/**
* pevent_filter_add_filter_str - add a new filter
* @filter: the event filter to add to
* @filter_str: the filter string that contains the filter
*
* Returns 0 if the filter was successfully added or a
* negative error code. Use pevent_filter_strerror() to see
* actual error message in case of error.
*/
enum pevent_errno pevent_filter_add_filter_str(struct event_filter *filter,
const char *filter_str)
{
struct pevent *pevent = filter->pevent;
struct event_list *event;
struct event_list *events = NULL;
const char *filter_start;
const char *next_event;
char *this_event;
char *event_name = NULL;
char *sys_name = NULL;
char *sp;
enum pevent_errno rtn = 0; /* PEVENT_ERRNO__SUCCESS */
int len;
int ret;
filter_init_error_buf(filter);
filter_start = strchr(filter_str, ':');
if (filter_start)
len = filter_start - filter_str;
else
len = strlen(filter_str);
do {
next_event = strchr(filter_str, ',');
if (next_event &&
(!filter_start || next_event < filter_start))
len = next_event - filter_str;
else if (filter_start)
len = filter_start - filter_str;
else
len = strlen(filter_str);
this_event = malloc(len + 1);
if (this_event == NULL) {
/* This can only happen when events is NULL, but still */
free_events(events);
return PEVENT_ERRNO__MEM_ALLOC_FAILED;
}
memcpy(this_event, filter_str, len);
this_event[len] = 0;
if (next_event)
next_event++;
filter_str = next_event;
sys_name = strtok_r(this_event, "/", &sp);
event_name = strtok_r(NULL, "/", &sp);
if (!sys_name) {
/* This can only happen when events is NULL, but still */
free_events(events);
free(this_event);
return PEVENT_ERRNO__FILTER_NOT_FOUND;
}
/* Find this event */
ret = find_event(pevent, &events, strim(sys_name), strim(event_name));
if (ret < 0) {
free_events(events);
free(this_event);
return ret;
}
free(this_event);
} while (filter_str);
/* Skip the ':' */
if (filter_start)
filter_start++;
/* filter starts here */
for (event = events; event; event = event->next) {
ret = filter_event(filter, event->event, filter_start,
filter->error_buffer);
/* Failures are returned if a parse error happened */
if (ret < 0)
rtn = ret;
if (ret >= 0 && pevent->test_filters) {
char *test;
test = pevent_filter_make_string(filter, event->event->id);
if (test) {
printf(" '%s: %s'\n", event->event->name, test);
free(test);
}
}
}
free_events(events);
if (rtn >= 0 && pevent->test_filters)
exit(0);
return rtn;
}
static void free_filter_type(struct filter_type *filter_type)
{
free_arg(filter_type->filter);
}
/**
* pevent_filter_strerror - fill error message in a buffer
* @filter: the event filter contains error
* @err: the error code
* @buf: the buffer to be filled in
* @buflen: the size of the buffer
*
* Returns 0 if message was filled successfully, -1 if error
*/
int pevent_filter_strerror(struct event_filter *filter, enum pevent_errno err,
char *buf, size_t buflen)
{
if (err <= __PEVENT_ERRNO__START || err >= __PEVENT_ERRNO__END)
return -1;
if (strlen(filter->error_buffer) > 0) {
size_t len = snprintf(buf, buflen, "%s", filter->error_buffer);
if (len > buflen)
return -1;
return 0;
}
return pevent_strerror(filter->pevent, err, buf, buflen);
}
/**
* pevent_filter_remove_event - remove a filter for an event
* @filter: the event filter to remove from
* @event_id: the event to remove a filter for
*
* Removes the filter saved for an event defined by @event_id
* from the @filter.
*
* Returns 1: if an event was removed
* 0: if the event was not found
*/
int pevent_filter_remove_event(struct event_filter *filter,
int event_id)
{
struct filter_type *filter_type;
unsigned long len;
if (!filter->filters)
return 0;
filter_type = find_filter_type(filter, event_id);
if (!filter_type)
return 0;
free_filter_type(filter_type);
/* The filter_type points into the event_filters array */
len = (unsigned long)(filter->event_filters + filter->filters) -
(unsigned long)(filter_type + 1);
memmove(filter_type, filter_type + 1, len);
filter->filters--;
memset(&filter->event_filters[filter->filters], 0,
sizeof(*filter_type));
return 1;
}
/**
* pevent_filter_reset - clear all filters in a filter
* @filter: the event filter to reset
*
* Removes all filters from a filter and resets it.
*/
void pevent_filter_reset(struct event_filter *filter)
{
int i;
for (i = 0; i < filter->filters; i++)
free_filter_type(&filter->event_filters[i]);
free(filter->event_filters);
filter->filters = 0;
filter->event_filters = NULL;
}
void pevent_filter_free(struct event_filter *filter)
{
pevent_unref(filter->pevent);
pevent_filter_reset(filter);
free(filter);
}
static char *arg_to_str(struct event_filter *filter, struct filter_arg *arg);
static int copy_filter_type(struct event_filter *filter,
struct event_filter *source,
struct filter_type *filter_type)
{
struct filter_arg *arg;
struct event_format *event;
const char *sys;
const char *name;
char *str;
/* Can't assume that the pevent's are the same */
sys = filter_type->event->system;
name = filter_type->event->name;
event = pevent_find_event_by_name(filter->pevent, sys, name);
if (!event)
return -1;
str = arg_to_str(source, filter_type->filter);
if (!str)
return -1;
if (strcmp(str, "TRUE") == 0 || strcmp(str, "FALSE") == 0) {
/* Add trivial event */
arg = allocate_arg();
if (arg == NULL)
return -1;
arg->type = FILTER_ARG_BOOLEAN;
if (strcmp(str, "TRUE") == 0)
arg->boolean.value = 1;
else
arg->boolean.value = 0;
filter_type = add_filter_type(filter, event->id);
if (filter_type == NULL)
return -1;
filter_type->filter = arg;
free(str);
return 0;
}
filter_event(filter, event, str, NULL);
free(str);
return 0;
}
/**
* pevent_filter_copy - copy a filter using another filter
* @dest - the filter to copy to
* @source - the filter to copy from
*
* Returns 0 on success and -1 if not all filters were copied
*/
int pevent_filter_copy(struct event_filter *dest, struct event_filter *source)
{
int ret = 0;
int i;
pevent_filter_reset(dest);
for (i = 0; i < source->filters; i++) {
if (copy_filter_type(dest, source, &source->event_filters[i]))
ret = -1;
}
return ret;
}
/**
* pevent_update_trivial - update the trivial filters with the given filter
* @dest - the filter to update
* @source - the filter as the source of the update
* @type - the type of trivial filter to update.
*
* Scan dest for trivial events matching @type to replace with the source.
*
* Returns 0 on success and -1 if there was a problem updating, but
* events may have still been updated on error.
*/
int pevent_update_trivial(struct event_filter *dest, struct event_filter *source,
enum filter_trivial_type type)
{
struct pevent *src_pevent;
struct pevent *dest_pevent;
struct event_format *event;
struct filter_type *filter_type;
struct filter_arg *arg;
char *str;
int i;
src_pevent = source->pevent;
dest_pevent = dest->pevent;
/* Do nothing if either of the filters has nothing to filter */
if (!dest->filters || !source->filters)
return 0;
for (i = 0; i < dest->filters; i++) {
filter_type = &dest->event_filters[i];
arg = filter_type->filter;
if (arg->type != FILTER_ARG_BOOLEAN)
continue;
if ((arg->boolean.value && type == FILTER_TRIVIAL_FALSE) ||
(!arg->boolean.value && type == FILTER_TRIVIAL_TRUE))
continue;
event = filter_type->event;
if (src_pevent != dest_pevent) {
/* do a look up */
event = pevent_find_event_by_name(src_pevent,
event->system,
event->name);
if (!event)
return -1;
}
str = pevent_filter_make_string(source, event->id);
if (!str)
continue;
/* Don't bother if the filter is trivial too */
if (strcmp(str, "TRUE") != 0 && strcmp(str, "FALSE") != 0)
filter_event(dest, event, str, NULL);
free(str);
}
return 0;
}
/**
* pevent_filter_clear_trivial - clear TRUE and FALSE filters
* @filter: the filter to remove trivial filters from
* @type: remove only true, false, or both
*
* Removes filters that only contain a TRUE or FALES boolean arg.
*
* Returns 0 on success and -1 if there was a problem.
*/
int pevent_filter_clear_trivial(struct event_filter *filter,
enum filter_trivial_type type)
{
struct filter_type *filter_type;
int count = 0;
int *ids = NULL;
int i;
if (!filter->filters)
return 0;
/*
* Two steps, first get all ids with trivial filters.
* then remove those ids.
*/
for (i = 0; i < filter->filters; i++) {
int *new_ids;
filter_type = &filter->event_filters[i];
if (filter_type->filter->type != FILTER_ARG_BOOLEAN)
continue;
switch (type) {
case FILTER_TRIVIAL_FALSE:
if (filter_type->filter->boolean.value)
continue;
case FILTER_TRIVIAL_TRUE:
if (!filter_type->filter->boolean.value)
continue;
default:
break;
}
new_ids = realloc(ids, sizeof(*ids) * (count + 1));
if (!new_ids) {
free(ids);
return -1;
}
ids = new_ids;
ids[count++] = filter_type->event_id;
}
if (!count)
return 0;
for (i = 0; i < count; i++)
pevent_filter_remove_event(filter, ids[i]);
free(ids);
return 0;
}
/**
* pevent_filter_event_has_trivial - return true event contains trivial filter
* @filter: the filter with the information
* @event_id: the id of the event to test
* @type: trivial type to test for (TRUE, FALSE, EITHER)
*
* Returns 1 if the event contains a matching trivial type
* otherwise 0.
*/
int pevent_filter_event_has_trivial(struct event_filter *filter,
int event_id,
enum filter_trivial_type type)
{
struct filter_type *filter_type;
if (!filter->filters)
return 0;
filter_type = find_filter_type(filter, event_id);
if (!filter_type)
return 0;
if (filter_type->filter->type != FILTER_ARG_BOOLEAN)
return 0;
switch (type) {
case FILTER_TRIVIAL_FALSE:
return !filter_type->filter->boolean.value;
case FILTER_TRIVIAL_TRUE:
return filter_type->filter->boolean.value;
default:
return 1;
}
}
static int test_filter(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err);
static const char *
get_comm(struct event_format *event, struct pevent_record *record)
{
const char *comm;
int pid;
pid = pevent_data_pid(event->pevent, record);
comm = pevent_data_comm_from_pid(event->pevent, pid);
return comm;
}
static unsigned long long
get_value(struct event_format *event,
struct format_field *field, struct pevent_record *record)
{
unsigned long long val;
/* Handle our dummy "comm" field */
if (field == &comm) {
const char *name;
name = get_comm(event, record);
return (unsigned long)name;
}
pevent_read_number_field(field, record->data, &val);
if (!(field->flags & FIELD_IS_SIGNED))
return val;
switch (field->size) {
case 1:
return (char)val;
case 2:
return (short)val;
case 4:
return (int)val;
case 8:
return (long long)val;
}
return val;
}
static unsigned long long
get_arg_value(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err);
static unsigned long long
get_exp_value(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err)
{
unsigned long long lval, rval;
lval = get_arg_value(event, arg->exp.left, record, err);
rval = get_arg_value(event, arg->exp.right, record, err);
if (*err) {
/*
* There was an error, no need to process anymore.
*/
return 0;
}
switch (arg->exp.type) {
case FILTER_EXP_ADD:
return lval + rval;
case FILTER_EXP_SUB:
return lval - rval;
case FILTER_EXP_MUL:
return lval * rval;
case FILTER_EXP_DIV:
return lval / rval;
case FILTER_EXP_MOD:
return lval % rval;
case FILTER_EXP_RSHIFT:
return lval >> rval;
case FILTER_EXP_LSHIFT:
return lval << rval;
case FILTER_EXP_AND:
return lval & rval;
case FILTER_EXP_OR:
return lval | rval;
case FILTER_EXP_XOR:
return lval ^ rval;
case FILTER_EXP_NOT:
default:
if (!*err)
*err = PEVENT_ERRNO__INVALID_EXP_TYPE;
}
return 0;
}
static unsigned long long
get_arg_value(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err)
{
switch (arg->type) {
case FILTER_ARG_FIELD:
return get_value(event, arg->field.field, record);
case FILTER_ARG_VALUE:
if (arg->value.type != FILTER_NUMBER) {
if (!*err)
*err = PEVENT_ERRNO__NOT_A_NUMBER;
}
return arg->value.val;
case FILTER_ARG_EXP:
return get_exp_value(event, arg, record, err);
default:
if (!*err)
*err = PEVENT_ERRNO__INVALID_ARG_TYPE;
}
return 0;
}
static int test_num(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err)
{
unsigned long long lval, rval;
lval = get_arg_value(event, arg->num.left, record, err);
rval = get_arg_value(event, arg->num.right, record, err);
if (*err) {
/*
* There was an error, no need to process anymore.
*/
return 0;
}
switch (arg->num.type) {
case FILTER_CMP_EQ:
return lval == rval;
case FILTER_CMP_NE:
return lval != rval;
case FILTER_CMP_GT:
return lval > rval;
case FILTER_CMP_LT:
return lval < rval;
case FILTER_CMP_GE:
return lval >= rval;
case FILTER_CMP_LE:
return lval <= rval;
default:
if (!*err)
*err = PEVENT_ERRNO__ILLEGAL_INTEGER_CMP;
return 0;
}
}
static const char *get_field_str(struct filter_arg *arg, struct pevent_record *record)
{
struct event_format *event;
struct pevent *pevent;
unsigned long long addr;
const char *val = NULL;
char hex[64];
/* If the field is not a string convert it */
if (arg->str.field->flags & FIELD_IS_STRING) {
val = record->data + arg->str.field->offset;
/*
* We need to copy the data since we can't be sure the field
* is null terminated.
*/
if (*(val + arg->str.field->size - 1)) {
/* copy it */
memcpy(arg->str.buffer, val, arg->str.field->size);
/* the buffer is already NULL terminated */
val = arg->str.buffer;
}
} else {
event = arg->str.field->event;
pevent = event->pevent;
addr = get_value(event, arg->str.field, record);
if (arg->str.field->flags & (FIELD_IS_POINTER | FIELD_IS_LONG))
/* convert to a kernel symbol */
val = pevent_find_function(pevent, addr);
if (val == NULL) {
/* just use the hex of the string name */
snprintf(hex, 64, "0x%llx", addr);
val = hex;
}
}
return val;
}
static int test_str(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err)
{
const char *val;
if (arg->str.field == &comm)
val = get_comm(event, record);
else
val = get_field_str(arg, record);
switch (arg->str.type) {
case FILTER_CMP_MATCH:
return strcmp(val, arg->str.val) == 0;
case FILTER_CMP_NOT_MATCH:
return strcmp(val, arg->str.val) != 0;
case FILTER_CMP_REGEX:
/* Returns zero on match */
return !regexec(&arg->str.reg, val, 0, NULL, 0);
case FILTER_CMP_NOT_REGEX:
return regexec(&arg->str.reg, val, 0, NULL, 0);
default:
if (!*err)
*err = PEVENT_ERRNO__ILLEGAL_STRING_CMP;
return 0;
}
}
static int test_op(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err)
{
switch (arg->op.type) {
case FILTER_OP_AND:
return test_filter(event, arg->op.left, record, err) &&
test_filter(event, arg->op.right, record, err);
case FILTER_OP_OR:
return test_filter(event, arg->op.left, record, err) ||
test_filter(event, arg->op.right, record, err);
case FILTER_OP_NOT:
return !test_filter(event, arg->op.right, record, err);
default:
if (!*err)
*err = PEVENT_ERRNO__INVALID_OP_TYPE;
return 0;
}
}
static int test_filter(struct event_format *event, struct filter_arg *arg,
struct pevent_record *record, enum pevent_errno *err)
{
if (*err) {
/*
* There was an error, no need to process anymore.
*/
return 0;
}
switch (arg->type) {
case FILTER_ARG_BOOLEAN:
/* easy case */
return arg->boolean.value;
case FILTER_ARG_OP:
return test_op(event, arg, record, err);
case FILTER_ARG_NUM:
return test_num(event, arg, record, err);
case FILTER_ARG_STR:
return test_str(event, arg, record, err);
case FILTER_ARG_EXP:
case FILTER_ARG_VALUE:
case FILTER_ARG_FIELD:
/*
* Expressions, fields and values evaluate
* to true if they return non zero
*/
return !!get_arg_value(event, arg, record, err);
default:
if (!*err)
*err = PEVENT_ERRNO__INVALID_ARG_TYPE;
return 0;
}
}
/**
* pevent_event_filtered - return true if event has filter
* @filter: filter struct with filter information
* @event_id: event id to test if filter exists
*
* Returns 1 if filter found for @event_id
* otherwise 0;
*/
int pevent_event_filtered(struct event_filter *filter, int event_id)
{
struct filter_type *filter_type;
if (!filter->filters)
return 0;
filter_type = find_filter_type(filter, event_id);
return filter_type ? 1 : 0;
}
/**
* pevent_filter_match - test if a record matches a filter
* @filter: filter struct with filter information
* @record: the record to test against the filter
*
* Returns: match result or error code (prefixed with PEVENT_ERRNO__)
* FILTER_MATCH - filter found for event and @record matches
* FILTER_MISS - filter found for event and @record does not match
* FILTER_NOT_FOUND - no filter found for @record's event
* NO_FILTER - if no filters exist
* otherwise - error occurred during test
*/
enum pevent_errno pevent_filter_match(struct event_filter *filter,
struct pevent_record *record)
{
struct pevent *pevent = filter->pevent;
struct filter_type *filter_type;
int event_id;
int ret;
enum pevent_errno err = 0;
filter_init_error_buf(filter);
if (!filter->filters)
return PEVENT_ERRNO__NO_FILTER;
event_id = pevent_data_type(pevent, record);
filter_type = find_filter_type(filter, event_id);
if (!filter_type)
return PEVENT_ERRNO__FILTER_NOT_FOUND;
ret = test_filter(filter_type->event, filter_type->filter, record, &err);
if (err)
return err;
return ret ? PEVENT_ERRNO__FILTER_MATCH : PEVENT_ERRNO__FILTER_MISS;
}
static char *op_to_str(struct event_filter *filter, struct filter_arg *arg)
{
char *str = NULL;
char *left = NULL;
char *right = NULL;
char *op = NULL;
int left_val = -1;
int right_val = -1;
int val;
switch (arg->op.type) {
case FILTER_OP_AND:
op = "&&";
/* fall through */
case FILTER_OP_OR:
if (!op)
op = "||";
left = arg_to_str(filter, arg->op.left);
right = arg_to_str(filter, arg->op.right);
if (!left || !right)
break;
/* Try to consolidate boolean values */
if (strcmp(left, "TRUE") == 0)
left_val = 1;
else if (strcmp(left, "FALSE") == 0)
left_val = 0;
if (strcmp(right, "TRUE") == 0)
right_val = 1;
else if (strcmp(right, "FALSE") == 0)
right_val = 0;
if (left_val >= 0) {
if ((arg->op.type == FILTER_OP_AND && !left_val) ||
(arg->op.type == FILTER_OP_OR && left_val)) {
/* Just return left value */
str = left;
left = NULL;
break;
}
if (right_val >= 0) {
/* just evaluate this. */
val = 0;
switch (arg->op.type) {
case FILTER_OP_AND:
val = left_val && right_val;
break;
case FILTER_OP_OR:
val = left_val || right_val;
break;
default:
break;
}
asprintf(&str, val ? "TRUE" : "FALSE");
break;
}
}
if (right_val >= 0) {
if ((arg->op.type == FILTER_OP_AND && !right_val) ||
(arg->op.type == FILTER_OP_OR && right_val)) {
/* Just return right value */
str = right;
right = NULL;
break;
}
/* The right value is meaningless */
str = left;
left = NULL;
break;
}
asprintf(&str, "(%s) %s (%s)", left, op, right);
break;
case FILTER_OP_NOT:
op = "!";
right = arg_to_str(filter, arg->op.right);
if (!right)
break;
/* See if we can consolidate */
if (strcmp(right, "TRUE") == 0)
right_val = 1;
else if (strcmp(right, "FALSE") == 0)
right_val = 0;
if (right_val >= 0) {
/* just return the opposite */
asprintf(&str, right_val ? "FALSE" : "TRUE");
break;
}
asprintf(&str, "%s(%s)", op, right);
break;
default:
/* ?? */
break;
}
free(left);
free(right);
return str;
}
static char *val_to_str(struct event_filter *filter, struct filter_arg *arg)
{
char *str = NULL;
asprintf(&str, "%lld", arg->value.val);
return str;
}
static char *field_to_str(struct event_filter *filter, struct filter_arg *arg)
{
return strdup(arg->field.field->name);
}
static char *exp_to_str(struct event_filter *filter, struct filter_arg *arg)
{
char *lstr;
char *rstr;
char *op;
char *str = NULL;
lstr = arg_to_str(filter, arg->exp.left);
rstr = arg_to_str(filter, arg->exp.right);
if (!lstr || !rstr)
goto out;
switch (arg->exp.type) {
case FILTER_EXP_ADD:
op = "+";
break;
case FILTER_EXP_SUB:
op = "-";
break;
case FILTER_EXP_MUL:
op = "*";
break;
case FILTER_EXP_DIV:
op = "/";
break;
case FILTER_EXP_MOD:
op = "%";
break;
case FILTER_EXP_RSHIFT:
op = ">>";
break;
case FILTER_EXP_LSHIFT:
op = "<<";
break;
case FILTER_EXP_AND:
op = "&";
break;
case FILTER_EXP_OR:
op = "|";
break;
case FILTER_EXP_XOR:
op = "^";
break;
default:
op = "[ERROR IN EXPRESSION TYPE]";
break;
}
asprintf(&str, "%s %s %s", lstr, op, rstr);
out:
free(lstr);
free(rstr);
return str;
}
static char *num_to_str(struct event_filter *filter, struct filter_arg *arg)
{
char *lstr;
char *rstr;
char *str = NULL;
char *op = NULL;
lstr = arg_to_str(filter, arg->num.left);
rstr = arg_to_str(filter, arg->num.right);
if (!lstr || !rstr)
goto out;
switch (arg->num.type) {
case FILTER_CMP_EQ:
op = "==";
/* fall through */
case FILTER_CMP_NE:
if (!op)
op = "!=";
/* fall through */
case FILTER_CMP_GT:
if (!op)
op = ">";
/* fall through */
case FILTER_CMP_LT:
if (!op)
op = "<";
/* fall through */
case FILTER_CMP_GE:
if (!op)
op = ">=";
/* fall through */
case FILTER_CMP_LE:
if (!op)
op = "<=";
asprintf(&str, "%s %s %s", lstr, op, rstr);
break;
default:
/* ?? */
break;
}
out:
free(lstr);
free(rstr);
return str;
}
static char *str_to_str(struct event_filter *filter, struct filter_arg *arg)
{
char *str = NULL;
char *op = NULL;
switch (arg->str.type) {
case FILTER_CMP_MATCH:
op = "==";
/* fall through */
case FILTER_CMP_NOT_MATCH:
if (!op)
op = "!=";
/* fall through */
case FILTER_CMP_REGEX:
if (!op)
op = "=~";
/* fall through */
case FILTER_CMP_NOT_REGEX:
if (!op)
op = "!~";
asprintf(&str, "%s %s \"%s\"",
arg->str.field->name, op, arg->str.val);
break;
default:
/* ?? */
break;
}
return str;
}
static char *arg_to_str(struct event_filter *filter, struct filter_arg *arg)
{
char *str = NULL;
switch (arg->type) {
case FILTER_ARG_BOOLEAN:
asprintf(&str, arg->boolean.value ? "TRUE" : "FALSE");
return str;
case FILTER_ARG_OP:
return op_to_str(filter, arg);
case FILTER_ARG_NUM:
return num_to_str(filter, arg);
case FILTER_ARG_STR:
return str_to_str(filter, arg);
case FILTER_ARG_VALUE:
return val_to_str(filter, arg);
case FILTER_ARG_FIELD:
return field_to_str(filter, arg);
case FILTER_ARG_EXP:
return exp_to_str(filter, arg);
default:
/* ?? */
return NULL;
}
}
/**
* pevent_filter_make_string - return a string showing the filter
* @filter: filter struct with filter information
* @event_id: the event id to return the filter string with
*
* Returns a string that displays the filter contents.
* This string must be freed with free(str).
* NULL is returned if no filter is found or allocation failed.
*/
char *
pevent_filter_make_string(struct event_filter *filter, int event_id)
{
struct filter_type *filter_type;
if (!filter->filters)
return NULL;
filter_type = find_filter_type(filter, event_id);
if (!filter_type)
return NULL;
return arg_to_str(filter, filter_type->filter);
}
/**
* pevent_filter_compare - compare two filters and return if they are the same
* @filter1: Filter to compare with @filter2
* @filter2: Filter to compare with @filter1
*
* Returns:
* 1 if the two filters hold the same content.
* 0 if they do not.
*/
int pevent_filter_compare(struct event_filter *filter1, struct event_filter *filter2)
{
struct filter_type *filter_type1;
struct filter_type *filter_type2;
char *str1, *str2;
int result;
int i;
/* Do the easy checks first */
if (filter1->filters != filter2->filters)
return 0;
if (!filter1->filters && !filter2->filters)
return 1;
/*
* Now take a look at each of the events to see if they have the same
* filters to them.
*/
for (i = 0; i < filter1->filters; i++) {
filter_type1 = &filter1->event_filters[i];
filter_type2 = find_filter_type(filter2, filter_type1->event_id);
if (!filter_type2)
break;
if (filter_type1->filter->type != filter_type2->filter->type)
break;
switch (filter_type1->filter->type) {
case FILTER_TRIVIAL_FALSE:
case FILTER_TRIVIAL_TRUE:
/* trivial types just need the type compared */
continue;
default:
break;
}
/* The best way to compare complex filters is with strings */
str1 = arg_to_str(filter1, filter_type1->filter);
str2 = arg_to_str(filter2, filter_type2->filter);
if (str1 && str2)
result = strcmp(str1, str2) != 0;
else
/* bail out if allocation fails */
result = 1;
free(str1);
free(str2);
if (result)
break;
}
if (i < filter1->filters)
return 0;
return 1;
}