diff options
Diffstat (limited to 'src/libudev/libudev-enumerate.c')
| -rw-r--r-- | src/libudev/libudev-enumerate.c | 936 |
1 files changed, 936 insertions, 0 deletions
diff --git a/src/libudev/libudev-enumerate.c b/src/libudev/libudev-enumerate.c new file mode 100644 index 0000000000..7b9a732ce6 --- /dev/null +++ b/src/libudev/libudev-enumerate.c @@ -0,0 +1,936 @@ +/* + * libudev - interface to udev device information + * + * Copyright (C) 2008-2010 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 <stdbool.h> +#include <sys/stat.h> +#include <sys/param.h> + +#include "libudev.h" +#include "libudev-private.h" + +/** + * SECTION:libudev-enumerate + * @short_description: lookup and sort sys devices + * + * Lookup devices in the sys filesystem, filter devices by properties, + * and return a sorted list of devices. + */ + +struct syspath { + char *syspath; + size_t len; +}; + +/** + * udev_enumerate: + * + * Opaque object representing one device lookup/sort context. + */ +struct udev_enumerate { + struct udev *udev; + int refcount; + struct udev_list sysattr_match_list; + struct udev_list sysattr_nomatch_list; + struct udev_list subsystem_match_list; + struct udev_list subsystem_nomatch_list; + struct udev_list sysname_match_list; + struct udev_list properties_match_list; + struct udev_list tags_match_list; + struct udev_device *parent_match; + struct udev_list devices_list; + struct syspath *devices; + unsigned int devices_cur; + unsigned int devices_max; + bool devices_uptodate:1; + bool match_is_initialized; +}; + +/** + * udev_enumerate_new: + * @udev: udev library context + * + * Returns: an enumeration context + **/ +_public_ 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, &udev_enumerate->sysattr_match_list, false); + udev_list_init(udev, &udev_enumerate->sysattr_nomatch_list, false); + udev_list_init(udev, &udev_enumerate->subsystem_match_list, true); + udev_list_init(udev, &udev_enumerate->subsystem_nomatch_list, true); + udev_list_init(udev, &udev_enumerate->sysname_match_list, true); + udev_list_init(udev, &udev_enumerate->properties_match_list, false); + udev_list_init(udev, &udev_enumerate->tags_match_list, true); + udev_list_init(udev, &udev_enumerate->devices_list, false); + return udev_enumerate; +} + +/** + * udev_enumerate_ref: + * @udev_enumerate: context + * + * Take a reference of a enumeration context. + * + * Returns: the passed enumeration context + **/ +_public_ struct udev_enumerate *udev_enumerate_ref(struct udev_enumerate *udev_enumerate) +{ + if (udev_enumerate == NULL) + return NULL; + udev_enumerate->refcount++; + return udev_enumerate; +} + +/** + * udev_enumerate_unref: + * @udev_enumerate: context + * + * Drop a reference of an enumeration context. If the refcount reaches zero, + * all resources of the enumeration context will be released. + **/ +_public_ void udev_enumerate_unref(struct udev_enumerate *udev_enumerate) +{ + unsigned int i; + + if (udev_enumerate == NULL) + return; + udev_enumerate->refcount--; + if (udev_enumerate->refcount > 0) + return; + udev_list_cleanup(&udev_enumerate->sysattr_match_list); + udev_list_cleanup(&udev_enumerate->sysattr_nomatch_list); + udev_list_cleanup(&udev_enumerate->subsystem_match_list); + udev_list_cleanup(&udev_enumerate->subsystem_nomatch_list); + udev_list_cleanup(&udev_enumerate->sysname_match_list); + udev_list_cleanup(&udev_enumerate->properties_match_list); + udev_list_cleanup(&udev_enumerate->tags_match_list); + udev_device_unref(udev_enumerate->parent_match); + udev_list_cleanup(&udev_enumerate->devices_list); + for (i = 0; i < udev_enumerate->devices_cur; i++) + free(udev_enumerate->devices[i].syspath); + free(udev_enumerate->devices); + free(udev_enumerate); +} + +/** + * udev_enumerate_get_udev: + * @udev_enumerate: context + * + * Returns: the udev library context. + */ +_public_ struct udev *udev_enumerate_get_udev(struct udev_enumerate *udev_enumerate) +{ + if (udev_enumerate == NULL) + return NULL; + return udev_enumerate->udev; +} + +static int syspath_add(struct udev_enumerate *udev_enumerate, const char *syspath) +{ + char *path; + struct syspath *entry; + + /* double array size if needed */ + if (udev_enumerate->devices_cur >= udev_enumerate->devices_max) { + struct syspath *buf; + unsigned int add; + + add = udev_enumerate->devices_max; + if (add < 1024) + add = 1024; + buf = realloc(udev_enumerate->devices, (udev_enumerate->devices_max + add) * sizeof(struct syspath)); + if (buf == NULL) + return -ENOMEM; + udev_enumerate->devices = buf; + udev_enumerate->devices_max += add; + } + + path = strdup(syspath); + if (path == NULL) + return -ENOMEM; + entry = &udev_enumerate->devices[udev_enumerate->devices_cur]; + entry->syspath = path; + entry->len = strlen(path); + udev_enumerate->devices_cur++; + udev_enumerate->devices_uptodate = false; + return 0; +} + +static int syspath_cmp(const void *p1, const void *p2) +{ + const struct syspath *path1 = p1; + const struct syspath *path2 = p2; + size_t len; + int ret; + + len = MIN(path1->len, path2->len); + ret = memcmp(path1->syspath, path2->syspath, len); + if (ret == 0) { + if (path1->len < path2->len) + ret = -1; + else if (path1->len > path2->len) + ret = 1; + } + return ret; +} + +/* For devices that should be moved to the absolute end of the list */ +static bool devices_delay_end(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) + return true; + } + return false; +} + +/* For devices that should just be moved a little bit later, just + * before the point where some common path prefix changes. Returns the + * number of characters that make up that common prefix */ +static size_t devices_delay_later(struct udev *udev, const char *syspath) +{ + const char *c; + + /* For sound cards the control device must be enumerated last + * to make sure it's the final device node that gets ACLs + * applied. Applications rely on this fact and use ACL changes + * on the control node as an indicator that the ACL change of + * the entire sound card completed. The kernel makes this + * guarantee when creating those devices, and hence we should + * too when enumerating them. */ + + if ((c = strstr(syspath, "/sound/card"))) { + c += 11; + c += strcspn(c, "/"); + + if (strncmp(c, "/controlC", 9) == 0) + return c - syspath + 1; + } + + return 0; +} + +/** + * udev_enumerate_get_list_entry: + * @udev_enumerate: context + * + * Returns: the first entry of the sorted list of device paths. + */ +_public_ struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enumerate *udev_enumerate) +{ + if (udev_enumerate == NULL) + return NULL; + if (!udev_enumerate->devices_uptodate) { + unsigned int i; + unsigned int max; + struct syspath *prev = NULL, *move_later = NULL; + size_t move_later_prefix = 0; + + udev_list_cleanup(&udev_enumerate->devices_list); + qsort(udev_enumerate->devices, udev_enumerate->devices_cur, sizeof(struct syspath), syspath_cmp); + + max = udev_enumerate->devices_cur; + for (i = 0; i < max; i++) { + struct syspath *entry = &udev_enumerate->devices[i]; + + /* skip duplicated entries */ + if (prev != NULL && + entry->len == prev->len && + memcmp(entry->syspath, prev->syspath, entry->len) == 0) + continue; + prev = entry; + + /* skip to be delayed devices, and add them to the end of the list */ + if (devices_delay_end(udev_enumerate->udev, entry->syspath)) { + syspath_add(udev_enumerate, entry->syspath); + /* need to update prev here for the case realloc() gives a different address */ + prev = &udev_enumerate->devices[i]; + continue; + } + + /* skip to be delayed devices, and move the to + * the point where the prefix changes. We can + * only move one item at a time. */ + if (!move_later) { + move_later_prefix = devices_delay_later(udev_enumerate->udev, entry->syspath); + + if (move_later_prefix > 0) { + move_later = entry; + continue; + } + } + + if (move_later && + strncmp(entry->syspath, move_later->syspath, move_later_prefix) != 0) { + + udev_list_entry_add(&udev_enumerate->devices_list, move_later->syspath, NULL); + move_later = NULL; + } + + udev_list_entry_add(&udev_enumerate->devices_list, entry->syspath, NULL); + } + + if (move_later) + udev_list_entry_add(&udev_enumerate->devices_list, move_later->syspath, NULL); + + /* add and cleanup delayed devices from end of list */ + for (i = max; i < udev_enumerate->devices_cur; i++) { + struct syspath *entry = &udev_enumerate->devices[i]; + + udev_list_entry_add(&udev_enumerate->devices_list, entry->syspath, NULL); + free(entry->syspath); + } + udev_enumerate->devices_cur = max; + + udev_enumerate->devices_uptodate = true; + } + return udev_list_get_entry(&udev_enumerate->devices_list); +} + +/** + * udev_enumerate_add_match_subsystem: + * @udev_enumerate: context + * @subsystem: filter for a subsystem of the device to include in the list + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ 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->subsystem_match_list, subsystem, NULL) == NULL) + return -ENOMEM; + return 0; +} + +/** + * udev_enumerate_add_nomatch_subsystem: + * @udev_enumerate: context + * @subsystem: filter for a subsystem of the device to exclude from the list + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ 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->subsystem_nomatch_list, subsystem, NULL) == NULL) + return -ENOMEM; + return 0; +} + +/** + * udev_enumerate_add_match_sysattr: + * @udev_enumerate: context + * @sysattr: filter for a sys attribute at the device to include in the list + * @value: optional value of the sys attribute + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ 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->sysattr_match_list, sysattr, value) == NULL) + return -ENOMEM; + return 0; +} + +/** + * udev_enumerate_add_nomatch_sysattr: + * @udev_enumerate: context + * @sysattr: filter for a sys attribute at the device to exclude from the list + * @value: optional value of the sys attribute + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ 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->sysattr_nomatch_list, sysattr, value) == NULL) + return -ENOMEM; + return 0; +} + +static int match_sysattr_value(struct udev_device *dev, const char *sysattr, const char *match_val) +{ + const char *val = NULL; + bool match = false; + + val = udev_device_get_sysattr_value(dev, sysattr); + if (val == NULL) + goto exit; + if (match_val == NULL) { + match = true; + goto exit; + } + if (fnmatch(match_val, val, 0) == 0) { + match = true; + goto exit; + } +exit: + return match; +} + +/** + * udev_enumerate_add_match_property: + * @udev_enumerate: context + * @property: filter for a property of the device to include in the list + * @value: value of the property + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ 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->properties_match_list, property, value) == NULL) + return -ENOMEM; + return 0; +} + +/** + * udev_enumerate_add_match_tag: + * @udev_enumerate: context + * @tag: filter for a tag of the device to include in the list + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumerate, const char *tag) +{ + if (udev_enumerate == NULL) + return -EINVAL; + if (tag == NULL) + return 0; + if (udev_list_entry_add(&udev_enumerate->tags_match_list, tag, NULL) == NULL) + return -ENOMEM; + return 0; +} + +/** + * udev_enumerate_add_match_parent: + * @udev_enumerate: context + * @parent: parent device where to start searching + * + * Return the devices on the subtree of one given device. The parent + * itself is included in the list. + * + * A reference for the device is held until the udev_enumerate context + * is cleaned up. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *parent) +{ + if (udev_enumerate == NULL) + return -EINVAL; + if (parent == NULL) + return 0; + if (udev_enumerate->parent_match != NULL) + udev_device_unref(udev_enumerate->parent_match); + udev_enumerate->parent_match = udev_device_ref(parent); + return 0; +} + +/** + * udev_enumerate_add_match_is_initialized: + * @udev_enumerate: context + * + * Match only devices which udev has set up already. This makes + * sure, that the device node permissions and context are properly set + * and that network devices are fully renamed. + * + * Usually, devices which are found in the kernel but not already + * handled by udev, have still pending events. Services should subscribe + * to monitor events and wait for these devices to become ready, instead + * of using uninitialized devices. + * + * For now, this will not affect devices which do not have a device node + * and are not network interfaces. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_is_initialized(struct udev_enumerate *udev_enumerate) +{ + if (udev_enumerate == NULL) + return -EINVAL; + udev_enumerate->match_is_initialized = true; + return 0; +} + +/** + * udev_enumerate_add_match_sysname: + * @udev_enumerate: context + * @sysname: filter for the name of the device to include in the list + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname) +{ + if (udev_enumerate == NULL) + return -EINVAL; + if (sysname == NULL) + return 0; + if (udev_list_entry_add(&udev_enumerate->sysname_match_list, sysname, NULL) == NULL) + return -ENOMEM; + return 0; +} + +static bool match_sysattr(struct udev_enumerate *udev_enumerate, struct udev_device *dev) +{ + 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(dev, udev_list_entry_get_name(list_entry), + udev_list_entry_get_value(list_entry))) + return false; + } + /* 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(dev, udev_list_entry_get_name(list_entry), + udev_list_entry_get_value(list_entry))) + return false; + } + return true; + } + return true; +} + +static bool match_property(struct udev_enumerate *udev_enumerate, struct udev_device *dev) +{ + struct udev_list_entry *list_entry; + bool match = false; + + /* no match always matches */ + if (udev_list_get_entry(&udev_enumerate->properties_match_list) == NULL) + return true; + + /* loop over matches */ + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->properties_match_list)) { + const char *match_key = udev_list_entry_get_name(list_entry); + const char *match_value = udev_list_entry_get_value(list_entry); + struct udev_list_entry *property_entry; + + /* loop over device properties */ + udev_list_entry_foreach(property_entry, udev_device_get_properties_list_entry(dev)) { + const char *dev_key = udev_list_entry_get_name(property_entry); + const char *dev_value = udev_list_entry_get_value(property_entry); + + if (fnmatch(match_key, dev_key, 0) != 0) + continue; + if (match_value == NULL && dev_value == NULL) { + match = true; + goto out; + } + if (match_value == NULL || dev_value == NULL) + continue; + if (fnmatch(match_value, dev_value, 0) == 0) { + match = true; + goto out; + } + } + } +out: + return match; +} + +static bool match_tag(struct udev_enumerate *udev_enumerate, struct udev_device *dev) +{ + struct udev_list_entry *list_entry; + + /* no match always matches */ + if (udev_list_get_entry(&udev_enumerate->tags_match_list) == NULL) + return true; + + /* loop over matches */ + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->tags_match_list)) + if (!udev_device_has_tag(dev, udev_list_entry_get_name(list_entry))) + return false; + + return true; +} + +static bool match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *dev) +{ + const char *parent; + + if (udev_enumerate->parent_match == NULL) + return true; + + parent = udev_device_get_devpath(udev_enumerate->parent_match); + return strncmp(parent, udev_device_get_devpath(dev), strlen(parent)) == 0; +} + +static bool match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname) +{ + struct udev_list_entry *list_entry; + + if (udev_list_get_entry(&udev_enumerate->sysname_match_list) == NULL) + return true; + + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysname_match_list)) { + if (fnmatch(udev_list_entry_get_name(list_entry), sysname, 0) != 0) + continue; + return true; + } + return false; +} + +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) + util_strpcpyl(&s, l, "/", subdir2, NULL); + dir = opendir(path); + if (dir == NULL) + return -ENOENT; + for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) { + char syspath[UTIL_PATH_SIZE]; + struct udev_device *dev; + + if (dent->d_name[0] == '.') + continue; + + if (!match_sysname(udev_enumerate, dent->d_name)) + continue; + + util_strscpyl(syspath, sizeof(syspath), path, "/", dent->d_name, NULL); + dev = udev_device_new_from_syspath(udev_enumerate->udev, syspath); + if (dev == NULL) + continue; + + if (udev_enumerate->match_is_initialized) { + /* + * All devices with a device node or network interfaces + * possibly need udev to adjust the device node permission + * or context, or rename the interface before it can be + * reliably used from other processes. + * + * For now, we can only check these types of devices, we + * might not store a database, and have no way to find out + * for all other types of devices. + */ + if (!udev_device_get_is_initialized(dev) && + (major(udev_device_get_devnum(dev)) > 0 || udev_device_get_ifindex(dev) > 0)) + goto nomatch; + } + if (!match_parent(udev_enumerate, dev)) + goto nomatch; + if (!match_tag(udev_enumerate, dev)) + goto nomatch; + if (!match_property(udev_enumerate, dev)) + goto nomatch; + if (!match_sysattr(udev_enumerate, dev)) + goto nomatch; + + syspath_add(udev_enumerate, udev_device_get_syspath(dev)); +nomatch: + udev_device_unref(dev); + } + closedir(dir); + return 0; +} + +static bool 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 false; + } + 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 true; + } + return false; + } + return true; +} + +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; +} + +/** + * udev_enumerate_add_syspath: + * @udev_enumerate: context + * @syspath: path of a device + * + * Add a device to the list of devices, to retrieve it back sorted in dependency order. + * + * Returns: 0 on success, otherwise a negative error value. + */ +_public_ int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath) +{ + 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; + syspath_add(udev_enumerate, udev_device_get_syspath(udev_device)); + udev_device_unref(udev_device); + return 0; +} + +static int scan_devices_tags(struct udev_enumerate *udev_enumerate) +{ + struct udev *udev = udev_enumerate_get_udev(udev_enumerate); + struct udev_list_entry *list_entry; + + /* scan only tagged devices, use tags reverse-index, instead of searching all devices in /sys */ + udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->tags_match_list)) { + DIR *dir; + struct dirent *dent; + char path[UTIL_PATH_SIZE]; + + util_strscpyl(path, sizeof(path), udev_get_run_path(udev), "/tags/", + udev_list_entry_get_name(list_entry), NULL); + dir = opendir(path); + if (dir == NULL) + continue; + for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) { + struct udev_device *dev; + + if (dent->d_name[0] == '.') + continue; + + dev = udev_device_new_from_id_filename(udev_enumerate->udev, dent->d_name); + if (dev == NULL) + continue; + + if (!match_subsystem(udev_enumerate, udev_device_get_subsystem(dev))) + goto nomatch; + if (!match_sysname(udev_enumerate, udev_device_get_sysname(dev))) + goto nomatch; + if (!match_parent(udev_enumerate, dev)) + goto nomatch; + if (!match_property(udev_enumerate, dev)) + goto nomatch; + if (!match_sysattr(udev_enumerate, dev)) + goto nomatch; + + syspath_add(udev_enumerate, udev_device_get_syspath(dev)); +nomatch: + udev_device_unref(dev); + } + closedir(dir); + } + return 0; +} + +static int parent_add_child(struct udev_enumerate *enumerate, const char *path) +{ + struct udev_device *dev; + + dev = udev_device_new_from_syspath(enumerate->udev, path); + if (dev == NULL) + return -ENODEV; + + if (!match_subsystem(enumerate, udev_device_get_subsystem(dev))) + return 0; + if (!match_sysname(enumerate, udev_device_get_sysname(dev))) + return 0; + if (!match_property(enumerate, dev)) + return 0; + if (!match_sysattr(enumerate, dev)) + return 0; + + syspath_add(enumerate, udev_device_get_syspath(dev)); + udev_device_unref(dev); + return 1; +} + +static int parent_crawl_children(struct udev_enumerate *enumerate, const char *path, int maxdepth) +{ + DIR *d; + struct dirent *dent; + + d = opendir(path); + if (d == NULL) + return -errno; + + for (dent = readdir(d); dent != NULL; dent = readdir(d)) { + char *child; + + if (dent->d_name[0] == '.') + continue; + if (dent->d_type != DT_DIR) + continue; + if (asprintf(&child, "%s/%s", path, dent->d_name) < 0) + continue; + parent_add_child(enumerate, child); + if (maxdepth > 0) + parent_crawl_children(enumerate, child, maxdepth-1); + free(child); + } + + closedir(d); + return 0; +} + +static int scan_devices_children(struct udev_enumerate *enumerate) +{ + const char *path; + + path = udev_device_get_syspath(enumerate->parent_match); + parent_add_child(enumerate, path); + return parent_crawl_children(enumerate, path, 256); +} + +static int scan_devices_all(struct udev_enumerate *udev_enumerate) +{ + struct udev *udev = udev_enumerate_get_udev(udev_enumerate); + char base[UTIL_PATH_SIZE]; + struct stat statbuf; + + 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 */ + scan_dir(udev_enumerate, "subsystem", "devices", NULL); + } else { + scan_dir(udev_enumerate, "bus", "devices", NULL); + scan_dir(udev_enumerate, "class", NULL, NULL); + } + return 0; +} + +/** + * udev_enumerate_scan_devices: + * @udev_enumerate: udev enumeration context + * + * Returns: 0 on success, otherwise a negative error value. + **/ +_public_ int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate) +{ + if (udev_enumerate == NULL) + return -EINVAL; + + /* efficiently lookup tags only, we maintain a reverse-index */ + if (udev_list_get_entry(&udev_enumerate->tags_match_list) != NULL) + return scan_devices_tags(udev_enumerate); + + /* walk the subtree of one parent device only */ + if (udev_enumerate->parent_match != NULL) + return scan_devices_children(udev_enumerate); + + /* scan devices of all subsystems */ + return scan_devices_all(udev_enumerate); +} + +/** + * udev_enumerate_scan_subsystems: + * @udev_enumerate: udev enumeration context + * + * Returns: 0 on success, otherwise a negative error value. + **/ +_public_ 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; + + /* all kernel modules */ + if (match_subsystem(udev_enumerate, "module")) + scan_dir_and_add_devices(udev_enumerate, "module", NULL, NULL); + + util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL); + if (stat(base, &statbuf) == 0) + subsysdir = "subsystem"; + else + subsysdir = "bus"; + + /* all subsystems (only buses support coldplug) */ + if (match_subsystem(udev_enumerate, "subsystem")) + scan_dir_and_add_devices(udev_enumerate, subsysdir, NULL, NULL); + + /* all subsystem drivers */ + if (match_subsystem(udev_enumerate, "drivers")) + scan_dir(udev_enumerate, subsysdir, "drivers", "drivers"); + return 0; +} |