libudev-enumerate.c revision 065db052211d3bf08d9b0f698a79a8798faf11d2
/*
* libudev - interface to udev device information
*
* Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
*
* This library 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; either
* version 2.1 of the License, or (at your option) any later version.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <dirent.h>
#include <fnmatch.h>
#include <sys/stat.h>
#include "libudev.h"
#include "libudev-private.h"
static int devices_sort(struct udev_enumerate *udev_enumerate);
struct udev_enumerate {
struct udev *udev;
int refcount;
struct udev_list_node sysattr_match_list;
struct udev_list_node sysattr_nomatch_list;
struct udev_list_node subsystem_match_list;
struct udev_list_node subsystem_nomatch_list;
struct udev_list_node properties_match_list;
struct udev_list_node devices_list;
int devices_sorted;
};
/**
* udev_enumerate_new:
* @udev: udev library context
*
* Returns: an enumeration context
**/
struct udev_enumerate *udev_enumerate_new(struct udev *udev)
{
struct udev_enumerate *udev_enumerate;
udev_enumerate = calloc(1, sizeof(struct udev_enumerate));
if (udev_enumerate == NULL)
return NULL;
udev_enumerate->refcount = 1;
udev_enumerate->udev = udev;
udev_list_init(&udev_enumerate->devices_list);
udev_list_init(&udev_enumerate->sysattr_match_list);
udev_list_init(&udev_enumerate->sysattr_nomatch_list);
udev_list_init(&udev_enumerate->subsystem_match_list);
udev_list_init(&udev_enumerate->subsystem_nomatch_list);
udev_list_init(&udev_enumerate->properties_match_list);
return udev_enumerate;
}
struct udev_enumerate *udev_enumerate_ref(struct udev_enumerate *udev_enumerate)
{
if (udev_enumerate == NULL)
return NULL;
udev_enumerate->refcount++;
return udev_enumerate;
}
void udev_enumerate_unref(struct udev_enumerate *udev_enumerate)
{
if (udev_enumerate == NULL)
return;
udev_enumerate->refcount--;
if (udev_enumerate->refcount > 0)
return;
udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->devices_list);
udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysattr_match_list);
udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysattr_nomatch_list);
udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->subsystem_match_list);
udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->subsystem_nomatch_list);
udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->properties_match_list);
free(udev_enumerate);
}
struct udev *udev_enumerate_get_udev(struct udev_enumerate *udev_enumerate)
{
if (udev_enumerate == NULL)
return NULL;
return udev_enumerate->udev;
}
struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enumerate *udev_enumerate)
{
if (udev_enumerate == NULL)
return NULL;
if (!udev_enumerate->devices_sorted)
devices_sort(udev_enumerate);
return udev_list_get_entry(&udev_enumerate->devices_list);
}
int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
{
if (udev_enumerate == NULL)
return -EINVAL;
if (subsystem == NULL)
return 0;
if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
&udev_enumerate->subsystem_match_list, subsystem, NULL, 1, 0) == NULL)
return -ENOMEM;
return 0;
}
int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
{
if (udev_enumerate == NULL)
return -EINVAL;
if (subsystem == NULL)
return 0;
if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
&udev_enumerate->subsystem_nomatch_list, subsystem, NULL, 1, 0) == NULL)
return -ENOMEM;
return 0;
}
int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value)
{
if (udev_enumerate == NULL)
return -EINVAL;
if (sysattr == NULL)
return 0;
if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
&udev_enumerate->sysattr_match_list, sysattr, value, 1, 0) == NULL)
return -ENOMEM;
return 0;
}
int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value)
{
if (udev_enumerate == NULL)
return -EINVAL;
if (sysattr == NULL)
return 0;
if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
&udev_enumerate->sysattr_nomatch_list, sysattr, value, 1, 0) == NULL)
return -ENOMEM;
return 0;
}
static int match_sysattr_value(struct udev *udev, const char *syspath, const char *sysattr, const char *match_val)
{
struct udev_device *device;
const char *val = NULL;
int match = 0;
device = udev_device_new_from_syspath(udev, syspath);
if (device == NULL)
return -EINVAL;
val = udev_device_get_sysattr_value(device, sysattr);
if (val == NULL)
goto exit;
if (match_val == NULL) {
match = 1;
goto exit;
}
if (fnmatch(match_val, val, 0) == 0) {
match = 1;
goto exit;
}
exit:
udev_device_unref(device);
return match;
}
int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value)
{
if (udev_enumerate == NULL)
return -EINVAL;
if (property == NULL)
return 0;
if (udev_list_entry_add(udev_enumerate_get_udev(udev_enumerate),
&udev_enumerate->properties_match_list, property, value, 1, 0) == NULL)
return -ENOMEM;
return 0;
}
static int match_sysattr(struct udev_enumerate *udev_enumerate, const char *syspath)
{
struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
struct udev_list_entry *list_entry;
/* skip list */
udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysattr_nomatch_list)) {
if (match_sysattr_value(udev, syspath,
udev_list_entry_get_name(list_entry),
udev_list_entry_get_value(list_entry)))
return 0;
}
/* include list */
if (udev_list_get_entry(&udev_enumerate->sysattr_match_list) != NULL) {
udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysattr_match_list)) {
/* anything that does not match, will make it FALSE */
if (!match_sysattr_value(udev, syspath,
udev_list_entry_get_name(list_entry),
udev_list_entry_get_value(list_entry)))
return 0;
}
return 1;
}
return 1;
}
static int match_property(struct udev_enumerate *udev_enumerate, const char *syspath)
{
struct udev_device *dev;
struct udev_list_entry *list_entry;
int match = 0;
/* no match always matches */
if (udev_list_get_entry(&udev_enumerate->properties_match_list) == NULL)
return 1;
/* no device does not match */
dev = udev_device_new_from_syspath(udev_enumerate->udev, syspath);
if (dev == NULL)
return 0;
/* loop over matches */
udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->properties_match_list)) {
struct udev_list_entry *property_entry;
/* loop over device properties */
udev_list_entry_foreach(property_entry, udev_device_get_properties_list_entry(dev)) {
if (fnmatch(udev_list_entry_get_name(list_entry), udev_list_entry_get_name(property_entry), 0) == 0) {
const char *match_value;
const char *dev_value;
match_value = udev_list_entry_get_value(list_entry);
dev_value = udev_list_entry_get_value(property_entry);
if (match_value == NULL && dev_value == NULL) {
match = 1;
goto out;
}
if (match_value == NULL || dev_value == NULL)
continue;
if (fnmatch(match_value, dev_value, 0) == 0) {
match = 1;
goto out;
}
}
}
}
out:
udev_device_unref(dev);
return match;
}
static int scan_dir_and_add_devices(struct udev_enumerate *udev_enumerate,
const char *basedir, const char *subdir1, const char *subdir2)
{
struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
char path[UTIL_PATH_SIZE];
size_t l;
char *s;
DIR *dir;
struct dirent *dent;
s = path;
l = util_strpcpyl(&s, sizeof(path), udev_get_sys_path(udev), "/", basedir, NULL);
if (subdir1 != NULL)
l = util_strpcpyl(&s, l, "/", subdir1, NULL);
if (subdir2 != NULL)
l = util_strpcpyl(&s, l, "/", subdir2, NULL);
dir = opendir(path);
if (dir == NULL)
return -1;
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
char syspath[UTIL_PATH_SIZE];
char filename[UTIL_PATH_SIZE];
struct stat statbuf;
if (dent->d_name[0] == '.')
continue;
util_strscpyl(syspath, sizeof(syspath), path, "/", dent->d_name, NULL);
if (lstat(syspath, &statbuf) != 0)
continue;
if (S_ISREG(statbuf.st_mode))
continue;
if (S_ISLNK(statbuf.st_mode))
util_resolve_sys_link(udev, syspath, sizeof(syspath));
util_strscpyl(filename, sizeof(filename), syspath, "/uevent", NULL);
if (stat(filename, &statbuf) != 0)
continue;
if (!match_sysattr(udev_enumerate, syspath))
continue;
if (!match_property(udev_enumerate, syspath))
continue;
udev_list_entry_add(udev, &udev_enumerate->devices_list, syspath, NULL, 1, 1);
}
closedir(dir);
return 0;
}
static int match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
{
struct udev_list_entry *list_entry;
udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->subsystem_nomatch_list)) {
if (fnmatch(udev_list_entry_get_name(list_entry), subsystem, 0) == 0)
return 0;
}
if (udev_list_get_entry(&udev_enumerate->subsystem_match_list) != NULL) {
udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->subsystem_match_list)) {
if (fnmatch(udev_list_entry_get_name(list_entry), subsystem, 0) == 0)
return 1;
}
return 0;
}
return 1;
}
static int scan_dir(struct udev_enumerate *udev_enumerate, const char *basedir, const char *subdir, const char *subsystem)
{
struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
char path[UTIL_PATH_SIZE];
DIR *dir;
struct dirent *dent;
util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), "/", basedir, NULL);
dir = opendir(path);
if (dir == NULL)
return -1;
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
if (dent->d_name[0] == '.')
continue;
if (!match_subsystem(udev_enumerate, subsystem != NULL ? subsystem : dent->d_name))
continue;
scan_dir_and_add_devices(udev_enumerate, basedir, dent->d_name, subdir);
}
closedir(dir);
return 0;
}
static int devices_delay(struct udev *udev, const char *syspath)
{
static const char *delay_device_list[] = {
"/block/md",
"/block/dm-",
NULL
};
size_t len;
int i;
len = strlen(udev_get_sys_path(udev));
for (i = 0; delay_device_list[i] != NULL; i++) {
if (strstr(&syspath[len], delay_device_list[i]) != NULL) {
dbg(udev, "delaying: %s\n", syspath);
return 1;
}
}
return 0;
}
/* sort delayed devices to the end of the list */
static int devices_sort(struct udev_enumerate *udev_enumerate)
{
struct udev_list_entry *entry_loop;
struct udev_list_entry *entry_tmp;
struct udev_list_node devices_list;
udev_list_init(&devices_list);
/* move delayed to delay list */
udev_list_entry_foreach_safe(entry_loop, entry_tmp, udev_list_get_entry(&udev_enumerate->devices_list)) {
if (devices_delay(udev_enumerate->udev, udev_list_entry_get_name(entry_loop))) {
udev_list_entry_remove(entry_loop);
udev_list_entry_append(entry_loop, &devices_list);
}
}
/* move delayed back to end of list */
udev_list_entry_foreach_safe(entry_loop, entry_tmp, udev_list_get_entry(&devices_list)) {
udev_list_entry_remove(entry_loop);
udev_list_entry_append(entry_loop, &udev_enumerate->devices_list);
}
udev_enumerate->devices_sorted = 1;
return 0;
}
int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath)
{
struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
struct udev_device *udev_device;
if (udev_enumerate == NULL)
return -EINVAL;
if (syspath == NULL)
return 0;
/* resolve to real syspath */
udev_device = udev_device_new_from_syspath(udev_enumerate->udev, syspath);
if (udev_device == NULL)
return -EINVAL;
udev_list_entry_add(udev, &udev_enumerate->devices_list,
udev_device_get_syspath(udev_device), NULL, 1, 1);
udev_device_unref(udev_device);
return 0;
}
/**
* udev_enumerate_scan_devices:
* @udev_enumerate: udev enumeration context
*
* Returns: a negative value on error.
**/
int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate)
{
struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
char base[UTIL_PATH_SIZE];
struct stat statbuf;
if (udev_enumerate == NULL)
return -EINVAL;
util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
if (stat(base, &statbuf) == 0) {
/* we have /subsystem/, forget all the old stuff */
dbg(udev, "searching '/subsystem/*/devices/*' dir\n");
scan_dir(udev_enumerate, "subsystem", "devices", NULL);
} else {
dbg(udev, "searching '/bus/*/devices/*' dir\n");
scan_dir(udev_enumerate, "bus", "devices", NULL);
dbg(udev, "searching '/class/*' dir\n");
scan_dir(udev_enumerate, "class", NULL, NULL);
/* if block isn't a class, scan /block/ */
util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/class/block", NULL);
if (stat(base, &statbuf) != 0) {
if (match_subsystem(udev_enumerate, "block")) {
dbg(udev, "searching '/block/*' dir\n");
/* scan disks */
scan_dir_and_add_devices(udev_enumerate, "block", NULL, NULL);
/* scan partitions */
dbg(udev, "searching '/block/*/*' dir\n");
scan_dir(udev_enumerate, "block", NULL, "block");
}
}
}
return 0;
}
/**
* udev_enumerate_scan_subsystems:
* @udev_enumerate: udev enumeration context
*
* Returns: a negative value on error.
**/
int udev_enumerate_scan_subsystems(struct udev_enumerate *udev_enumerate)
{
struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
char base[UTIL_PATH_SIZE];
struct stat statbuf;
const char *subsysdir;
if (udev_enumerate == NULL)
return -EINVAL;
util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
if (stat(base, &statbuf) == 0)
subsysdir = "subsystem";
else
subsysdir = "bus";
if (match_subsystem(udev_enumerate, "subsystem")) {
dbg(udev, "searching '%s/*' dir\n", subsysdir);
scan_dir_and_add_devices(udev_enumerate, subsysdir, NULL, NULL);
}
if (match_subsystem(udev_enumerate, "drivers")) {
dbg(udev, "searching '%s/*/drivers/*' dir\n", subsysdir);
scan_dir(udev_enumerate, subsysdir, "drivers", "drivers");
}
return 0;
}