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mirror of https://github.com/systemd/systemd-stable.git synced 2024-10-31 07:51:08 +03:00
systemd-stable/udev_rules_parse.c
kay.sievers@vrfy.org 821d0ec803 [PATCH] add RUN key to be able to run rule based notification
SUBSYSTEM=="block", RUN="/sbin/program"
  will execute the program only for block device events.

ACTION="remove", SUBSYSTEM=="block", RUN"/sbin/program"
  will execute the program, if a block device is removed.
2005-04-26 23:55:00 -07:00

481 lines
11 KiB
C

/*
* udev_rules_parse.c
*
* Userspace devfs
*
* Copyright (C) 2003,2004 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2003-2005 Kay Sievers <kay.sievers@vrfy.org>
*
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation version 2 of the License.
*
* 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <ctype.h>
#include <unistd.h>
#include <sys/stat.h>
#include <errno.h>
#include "udev_libc_wrapper.h"
#include "udev.h"
#include "udev_utils.h"
#include "logging.h"
#include "udev_rules.h"
LIST_HEAD(udev_rule_list);
static int add_config_dev(struct udev_rule *rule)
{
struct udev_rule *tmp_rule;
tmp_rule = malloc(sizeof(*tmp_rule));
if (tmp_rule == NULL)
return -ENOMEM;
memcpy(tmp_rule, rule, sizeof(struct udev_rule));
list_add_tail(&tmp_rule->node, &udev_rule_list);
dbg("name='%s', symlink='%s', bus='%s', id='%s', "
"sysfs_file[0]='%s', sysfs_value[0]='%s', "
"kernel='%s', program='%s', result='%s', "
"owner='%s', group='%s', mode=%#o, "
"all_partions=%u, ignore_remove=%u, ignore_device=%u, last_rule=%u",
rule->name, rule->symlink, rule->bus, rule->id,
rule->sysfs_pair[0].name, rule->sysfs_pair[0].value,
rule->kernel, rule->program, rule->result, rule->owner, rule->group, rule->mode,
rule->partitions, rule->ignore_remove, rule->ignore_device, rule->last_rule);
return 0;
}
static int get_key(char **line, char **key, enum key_operation *operation, char **value)
{
char *linepos;
char *temp;
linepos = *line;
if (!linepos)
return -1;
/* skip whitespace */
while (isspace(linepos[0]) || linepos[0] == ',')
linepos++;
/* get the key */
*key = linepos;
while (1) {
linepos++;
if (linepos[0] == '\0')
return -1;
if (isspace(linepos[0]))
break;
if (linepos[0] == '=')
break;
if (linepos[0] == '+')
break;
if (linepos[0] == '!')
break;
}
/* remember end of key */
temp = linepos;
/* skip whitespace after key */
while (isspace(linepos[0]))
linepos++;
/* get operation type */
if (linepos[0] == '=' && linepos[1] == '=') {
*operation = KEY_OP_MATCH;
linepos += 2;
dbg("operator=match");
} else if (linepos[0] == '!' && linepos[1] == '=') {
*operation = KEY_OP_NOMATCH;
linepos += 2;
dbg("operator=nomatch");
} else if (linepos[0] == '+' && linepos[1] == '=') {
*operation = KEY_OP_ADD;
linepos += 2;
dbg("operator=add");
} else if (linepos[0] == '=') {
*operation = KEY_OP_ASSIGN;
linepos++;
dbg("operator=assign");
} else
return -1;
/* terminate key */
temp[0] = '\0';
dbg("key='%s'", *key);
/* skip whitespace after operator */
while (isspace(linepos[0]))
linepos++;
/* get the value*/
if (linepos[0] == '"')
linepos++;
else
return -1;
*value = linepos;
temp = strchr(linepos, '"');
if (!temp)
return -1;
temp[0] = '\0';
temp++;
dbg("value='%s'", *value);
/* move line to next key */
*line = temp;
return 0;
}
/* extract possible KEY{attr} */
static char *get_key_attribute(char *str)
{
char *pos;
char *attr;
attr = strchr(str, '{');
if (attr != NULL) {
attr++;
pos = strchr(attr, '}');
if (pos == NULL) {
err("missing closing brace for format");
return NULL;
}
pos[0] = '\0';
dbg("attribute='%s'", attr);
return attr;
}
return NULL;
}
static int rules_parse(const char *filename)
{
char line[LINE_SIZE];
char *bufline;
int lineno;
char *linepos;
char *attr;
char *buf;
size_t bufsize;
size_t cur;
size_t count;
int program_given = 0;
int valid;
int retval = 0;
struct udev_rule rule;
if (file_map(filename, &buf, &bufsize) != 0) {
err("can't open '%s' as rules file", filename);
return -1;
}
dbg("reading '%s' as rules file", filename);
/* loop through the whole file */
cur = 0;
lineno = 0;
while (cur < bufsize) {
unsigned int i, j;
count = buf_get_line(buf, bufsize, cur);
bufline = &buf[cur];
cur += count+1;
lineno++;
if (count >= sizeof(line)) {
info("line too long, rule skipped %s, line %d", filename, lineno);
continue;
}
/* eat the whitespace */
while ((count > 0) && isspace(bufline[0])) {
bufline++;
count--;
}
if (count == 0)
continue;
/* see if this is a comment */
if (bufline[0] == COMMENT_CHARACTER)
continue;
/* skip backslash and newline from multi line rules */
for (i = j = 0; i < count; i++) {
if (bufline[i] == '\\' && bufline[i+1] == '\n')
continue;
line[j++] = bufline[i];
}
line[j] = '\0';
dbg("read '%s'", line);
/* get all known keys */
memset(&rule, 0x00, sizeof(struct udev_rule));
linepos = line;
valid = 0;
while (1) {
char *key;
char *value;
enum key_operation operation = KEY_OP_UNSET;
retval = get_key(&linepos, &key, &operation, &value);
if (retval)
break;
if (strcasecmp(key, KEY_KERNEL) == 0) {
strlcpy(rule.kernel, value, sizeof(rule.kernel));
rule.kernel_operation = operation;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_SUBSYSTEM) == 0) {
strlcpy(rule.subsystem, value, sizeof(rule.subsystem));
rule.subsystem_operation = operation;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_ACTION) == 0) {
strlcpy(rule.action, value, sizeof(rule.action));
rule.action_operation = operation;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_BUS) == 0) {
strlcpy(rule.bus, value, sizeof(rule.bus));
rule.bus_operation = operation;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_ID) == 0) {
strlcpy(rule.id, value, sizeof(rule.id));
rule.id_operation = operation;
valid = 1;
continue;
}
if (strncasecmp(key, KEY_SYSFS, sizeof(KEY_SYSFS)-1) == 0) {
struct key_pair *pair;
if (rule.sysfs_pair_count >= KEY_SYSFS_PAIRS_MAX) {
err("skip rule, to many " KEY_SYSFS " keys in a single rule");
goto error;
}
pair = &rule.sysfs_pair[rule.sysfs_pair_count];
attr = get_key_attribute(key + sizeof(KEY_SYSFS)-1);
if (attr == NULL) {
err("error parsing " KEY_SYSFS " attribute");
goto error;
}
strlcpy(pair->name, attr, sizeof(pair->name));
strlcpy(pair->value, value, sizeof(pair->value));
pair->operation = operation;
rule.sysfs_pair_count++;
valid = 1;
continue;
}
if (strncasecmp(key, KEY_ENV, sizeof(KEY_ENV)-1) == 0) {
struct key_pair *pair;
if (rule.env_pair_count >= KEY_ENV_PAIRS_MAX) {
err("skip rule, to many " KEY_ENV " keys in a single rule");
goto error;
}
pair = &rule.env_pair[rule.env_pair_count];
attr = get_key_attribute(key + sizeof(KEY_ENV)-1);
if (attr == NULL) {
err("error parsing " KEY_ENV " attribute");
continue;
}
strlcpy(pair->name, attr, sizeof(pair->name));
strlcpy(pair->value, value, sizeof(pair->value));
pair->operation = operation;
rule.env_pair_count++;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_DRIVER) == 0) {
strlcpy(rule.driver, value, sizeof(rule.driver));
rule.driver_operation = operation;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_RESULT) == 0) {
strlcpy(rule.result, value, sizeof(rule.result));
rule.result_operation = operation;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_PROGRAM) == 0) {
strlcpy(rule.program, value, sizeof(rule.program));
rule.program_operation = operation;
program_given = 1;
valid = 1;
continue;
}
if (strncasecmp(key, KEY_NAME, sizeof(KEY_NAME)-1) == 0) {
attr = get_key_attribute(key + sizeof(KEY_NAME)-1);
/* FIXME: remove old style options and make OPTIONS= mandatory */
if (attr != NULL) {
if (strstr(attr, OPTION_PARTITIONS) != NULL) {
dbg("creation of partition nodes requested");
rule.partitions = DEFAULT_PARTITIONS_COUNT;
}
if (strstr(attr, OPTION_IGNORE_REMOVE) != NULL) {
dbg("remove event should be ignored");
rule.ignore_remove = 1;
}
}
if (value[0] != '\0')
strlcpy(rule.name, value, sizeof(rule.name));
else
rule.ignore_device = 1;
valid = 1;
continue;
}
if (strcasecmp(key, KEY_SYMLINK) == 0) {
strlcpy(rule.symlink, value, sizeof(rule.symlink));
valid = 1;
continue;
}
if (strcasecmp(key, KEY_OWNER) == 0) {
strlcpy(rule.owner, value, sizeof(rule.owner));
valid = 1;
continue;
}
if (strcasecmp(key, KEY_GROUP) == 0) {
strlcpy(rule.group, value, sizeof(rule.group));
valid = 1;
continue;
}
if (strcasecmp(key, KEY_MODE) == 0) {
rule.mode = strtol(value, NULL, 8);
valid = 1;
continue;
}
if (strcasecmp(key, KEY_RUN) == 0) {
strlcpy(rule.run, value, sizeof(rule.run));
valid = 1;
continue;
}
if (strcasecmp(key, KEY_OPTIONS) == 0) {
if (strstr(value, OPTION_LAST_RULE) != NULL) {
dbg("last rule to be applied");
rule.last_rule = 1;
}
if (strstr(value, OPTION_IGNORE_DEVICE) != NULL) {
dbg("device should be ignored");
rule.ignore_device = 1;
}
if (strstr(value, OPTION_IGNORE_REMOVE) != NULL) {
dbg("remove event should be ignored");
rule.ignore_remove = 1;
}
if (strstr(value, OPTION_PARTITIONS) != NULL) {
dbg("creation of partition nodes requested");
rule.partitions = DEFAULT_PARTITIONS_COUNT;
}
valid = 1;
continue;
}
err("unknown key '%s'", key);
goto error;
}
/* skip line if not any valid key was found */
if (!valid)
goto error;
if ((rule.result[0] != '\0') && (program_given == 0)) {
info(KEY_RESULT " is only useful when " KEY_PROGRAM " is called in any rule before");
goto error;
}
rule.config_line = lineno;
strlcpy(rule.config_file, filename, sizeof(rule.config_file));
retval = add_config_dev(&rule);
if (retval) {
dbg("add_config_dev returned with error %d", retval);
continue;
error:
err("parse error %s, line %d:%d, rule skipped",
filename, lineno, (int) (linepos - line));
}
}
file_unmap(buf, bufsize);
return retval;
}
int udev_rules_init(void)
{
struct stat stats;
int retval;
if (stat(udev_rules_filename, &stats) != 0)
return -1;
if ((stats.st_mode & S_IFMT) != S_IFDIR)
retval = rules_parse(udev_rules_filename);
else {
struct name_entry *name_loop, *name_tmp;
LIST_HEAD(name_list);
retval = add_matching_files(&name_list, udev_rules_filename, RULEFILE_SUFFIX);
list_for_each_entry_safe(name_loop, name_tmp, &name_list, node) {
rules_parse(name_loop->name);
list_del(&name_loop->node);
}
}
return retval;
}
void udev_rules_close(void)
{
struct udev_rule *rule;
struct udev_rule *temp_rule;
list_for_each_entry_safe(rule, temp_rule, &udev_rule_list, node) {
list_del(&rule->node);
free(rule);
}
}