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-rw-r--r--src/device.c471
1 files changed, 471 insertions, 0 deletions
diff --git a/src/device.c b/src/device.c
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index 0000000000..e67d0a6c2d
--- /dev/null
+++ b/src/device.c
@@ -0,0 +1,471 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd 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; either version 2 of the License, or
+ (at your option) any later version.
+
+ systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <sys/epoll.h>
+#include <libudev.h>
+
+#include "unit.h"
+#include "device.h"
+#include "strv.h"
+#include "log.h"
+#include "unit-name.h"
+#include "dbus-device.h"
+
+static const UnitActiveState state_translation_table[_DEVICE_STATE_MAX] = {
+ [DEVICE_DEAD] = UNIT_INACTIVE,
+ [DEVICE_AVAILABLE] = UNIT_ACTIVE
+};
+
+static void device_done(Unit *u) {
+ Device *d = DEVICE(u);
+
+ assert(d);
+
+ free(d->sysfs);
+ d->sysfs = NULL;
+}
+
+static void device_set_state(Device *d, DeviceState state) {
+ DeviceState old_state;
+ assert(d);
+
+ old_state = d->state;
+ d->state = state;
+
+ if (state != old_state)
+ log_debug("%s changed %s -> %s",
+ UNIT(d)->meta.id,
+ device_state_to_string(old_state),
+ device_state_to_string(state));
+
+ unit_notify(UNIT(d), state_translation_table[old_state], state_translation_table[state]);
+}
+
+static int device_coldplug(Unit *u) {
+ Device *d = DEVICE(u);
+
+ assert(d);
+ assert(d->state == DEVICE_DEAD);
+
+ if (d->sysfs)
+ device_set_state(d, DEVICE_AVAILABLE);
+
+ return 0;
+}
+
+static void device_dump(Unit *u, FILE *f, const char *prefix) {
+ Device *d = DEVICE(u);
+
+ assert(d);
+
+ fprintf(f,
+ "%sDevice State: %s\n"
+ "%sSysfs Path: %s\n",
+ prefix, device_state_to_string(d->state),
+ prefix, strna(d->sysfs));
+}
+
+static UnitActiveState device_active_state(Unit *u) {
+ assert(u);
+
+ return state_translation_table[DEVICE(u)->state];
+}
+
+static const char *device_sub_state_to_string(Unit *u) {
+ assert(u);
+
+ return device_state_to_string(DEVICE(u)->state);
+}
+
+static int device_add_escaped_name(Unit *u, const char *dn, bool make_id) {
+ char *e;
+ int r;
+
+ assert(u);
+ assert(dn);
+ assert(dn[0] == '/');
+
+ if (!(e = unit_name_from_path(dn, ".device")))
+ return -ENOMEM;
+
+ r = unit_add_name(u, e);
+
+ if (r >= 0 && make_id)
+ unit_choose_id(u, e);
+
+ free(e);
+
+ if (r < 0 && r != -EEXIST)
+ return r;
+
+ return 0;
+}
+
+static int device_find_escape_name(Manager *m, const char *dn, Unit **_u) {
+ char *e;
+ Unit *u;
+
+ assert(m);
+ assert(dn);
+ assert(dn[0] == '/');
+ assert(_u);
+
+ if (!(e = unit_name_from_path(dn, ".device")))
+ return -ENOMEM;
+
+ u = manager_get_unit(m, e);
+ free(e);
+
+ if (u) {
+ *_u = u;
+ return 1;
+ }
+
+ return 0;
+}
+
+static int device_process_new_device(Manager *m, struct udev_device *dev, bool update_state) {
+ const char *dn, *wants, *sysfs, *expose, *model, *alias;
+ Unit *u = NULL;
+ int r;
+ char *w, *state;
+ size_t l;
+ bool delete;
+ struct udev_list_entry *item = NULL, *first = NULL;
+ int b;
+
+ assert(m);
+
+ if (!(sysfs = udev_device_get_syspath(dev)))
+ return -ENOMEM;
+
+ if (!(expose = udev_device_get_property_value(dev, "SYSTEMD_EXPOSE")))
+ return 0;
+
+ if ((b = parse_boolean(expose)) < 0) {
+ log_error("Failed to parse SYSTEMD_EXPOSE udev property for device %s: %s", sysfs, expose);
+ return 0;
+ }
+
+ if (!b)
+ return 0;
+
+ /* Check whether this entry is even relevant for us. */
+ dn = udev_device_get_devnode(dev);
+ wants = udev_device_get_property_value(dev, "SYSTEMD_WANTS");
+ alias = udev_device_get_property_value(dev, "SYSTEMD_ALIAS");
+
+ /* We allow exactly one alias to be configured a this time and
+ * it must be a path */
+
+ if (alias && !is_path(alias)) {
+ log_warning("SYSTEMD_ALIAS for %s is not a path, ignoring: %s", sysfs, alias);
+ alias = NULL;
+ }
+
+ if ((r = device_find_escape_name(m, sysfs, &u)) < 0)
+ return r;
+
+ if (r == 0 && dn)
+ if ((r = device_find_escape_name(m, dn, &u)) < 0)
+ return r;
+
+ if (r == 0) {
+ first = udev_device_get_devlinks_list_entry(dev);
+ udev_list_entry_foreach(item, first) {
+ if ((r = device_find_escape_name(m, udev_list_entry_get_name(item), &u)) < 0)
+ return r;
+
+ if (r > 0)
+ break;
+ }
+ }
+
+ if (r == 0 && alias)
+ if ((r = device_find_escape_name(m, alias, &u)) < 0)
+ return r;
+
+ /* FIXME: this needs proper merging */
+
+ assert((r > 0) == !!u);
+
+ /* If this is a different unit, then let's not merge things */
+ if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs))
+ u = NULL;
+
+ if (!u) {
+ delete = true;
+
+ if (!(u = unit_new(m)))
+ return -ENOMEM;
+
+ if ((r = device_add_escaped_name(u, sysfs, true)) < 0)
+ goto fail;
+
+ unit_add_to_load_queue(u);
+ } else
+ delete = false;
+
+ if (!(DEVICE(u)->sysfs))
+ if (!(DEVICE(u)->sysfs = strdup(sysfs))) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ if (alias)
+ if ((r = device_add_escaped_name(u, alias, true)) < 0)
+ goto fail;
+
+ if (dn)
+ if ((r = device_add_escaped_name(u, dn, true)) < 0)
+ goto fail;
+
+ first = udev_device_get_devlinks_list_entry(dev);
+ udev_list_entry_foreach(item, first)
+ if ((r = device_add_escaped_name(u, udev_list_entry_get_name(item), false)) < 0)
+ goto fail;
+
+ if ((model = udev_device_get_property_value(dev, "ID_MODEL_FROM_DATABASE")) ||
+ (model = udev_device_get_property_value(dev, "ID_MODEL"))) {
+ if ((r = unit_set_description(u, model)) < 0)
+ goto fail;
+ } else if (dn) {
+ if ((r = unit_set_description(u, dn)) < 0)
+ goto fail;
+ } else
+ if ((r = unit_set_description(u, sysfs)) < 0)
+ goto fail;
+
+ if (wants) {
+ FOREACH_WORD(w, l, wants, state) {
+ char *e;
+
+ if (!(e = strndup(w, l))) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ r = unit_add_dependency_by_name(u, UNIT_WANTS, NULL, e, true);
+ free(e);
+
+ if (r < 0)
+ goto fail;
+ }
+ }
+
+ if (update_state) {
+ manager_dispatch_load_queue(u->meta.manager);
+ device_set_state(DEVICE(u), DEVICE_AVAILABLE);
+ }
+
+ unit_add_to_dbus_queue(u);
+
+ return 0;
+
+fail:
+ if (delete && u)
+ unit_free(u);
+ return r;
+}
+
+static int device_process_path(Manager *m, const char *path, bool update_state) {
+ int r;
+ struct udev_device *dev;
+
+ assert(m);
+ assert(path);
+
+ if (!(dev = udev_device_new_from_syspath(m->udev, path))) {
+ log_warning("Failed to get udev device object from udev for path %s.", path);
+ return -ENOMEM;
+ }
+
+ r = device_process_new_device(m, dev, update_state);
+ udev_device_unref(dev);
+ return r;
+}
+
+static int device_process_removed_device(Manager *m, struct udev_device *dev) {
+ const char *sysfs;
+ char *e;
+ Unit *u;
+ Device *d;
+
+ assert(m);
+ assert(dev);
+
+ if (!(sysfs = udev_device_get_syspath(dev)))
+ return -ENOMEM;
+
+ assert(sysfs[0] == '/');
+ if (!(e = unit_name_from_path(sysfs, ".device")))
+ return -ENOMEM;
+
+ u = manager_get_unit(m, e);
+ free(e);
+
+ if (!u)
+ return 0;
+
+ d = DEVICE(u);
+ free(d->sysfs);
+ d->sysfs = NULL;
+
+ device_set_state(d, DEVICE_DEAD);
+ return 0;
+}
+
+static void device_shutdown(Manager *m) {
+ assert(m);
+
+ if (m->udev_monitor) {
+ udev_monitor_unref(m->udev_monitor);
+ m->udev_monitor = NULL;
+ }
+
+ if (m->udev) {
+ udev_unref(m->udev);
+ m->udev = NULL;
+ }
+}
+
+static int device_enumerate(Manager *m) {
+ struct epoll_event ev;
+ int r;
+ struct udev_enumerate *e = NULL;
+ struct udev_list_entry *item = NULL, *first = NULL;
+
+ assert(m);
+
+ if (!m->udev) {
+ if (!(m->udev = udev_new()))
+ return -ENOMEM;
+
+ if (!(m->udev_monitor = udev_monitor_new_from_netlink(m->udev, "udev"))) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ if (udev_monitor_enable_receiving(m->udev_monitor) < 0) {
+ r = -EIO;
+ goto fail;
+ }
+
+ m->udev_watch.type = WATCH_UDEV;
+ m->udev_watch.fd = udev_monitor_get_fd(m->udev_monitor);
+
+ zero(ev);
+ ev.events = EPOLLIN;
+ ev.data.ptr = &m->udev_watch;
+
+ if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->udev_watch.fd, &ev) < 0)
+ return -errno;
+ }
+
+ if (!(e = udev_enumerate_new(m->udev))) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ if (udev_enumerate_scan_devices(e) < 0) {
+ r = -EIO;
+ goto fail;
+ }
+
+ first = udev_enumerate_get_list_entry(e);
+ udev_list_entry_foreach(item, first)
+ device_process_path(m, udev_list_entry_get_name(item), false);
+
+ udev_enumerate_unref(e);
+ return 0;
+
+fail:
+ if (e)
+ udev_enumerate_unref(e);
+
+ device_shutdown(m);
+ return r;
+}
+
+void device_fd_event(Manager *m, int events) {
+ struct udev_device *dev;
+ int r;
+ const char *action;
+
+ assert(m);
+ assert(events == EPOLLIN);
+
+ if (!(dev = udev_monitor_receive_device(m->udev_monitor))) {
+ log_error("Failed to receive device.");
+ return;
+ }
+
+ if (!(action = udev_device_get_action(dev))) {
+ log_error("Failed to get udev action string.");
+ goto fail;
+ }
+
+ if (streq(action, "remove")) {
+ if ((r = device_process_removed_device(m, dev)) < 0) {
+ log_error("Failed to process udev device event: %s", strerror(-r));
+ goto fail;
+ }
+ } else {
+ if ((r = device_process_new_device(m, dev, true)) < 0) {
+ log_error("Failed to process udev device event: %s", strerror(-r));
+ goto fail;
+ }
+ }
+
+fail:
+ udev_device_unref(dev);
+}
+
+static const char* const device_state_table[_DEVICE_STATE_MAX] = {
+ [DEVICE_DEAD] = "dead",
+ [DEVICE_AVAILABLE] = "available"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(device_state, DeviceState);
+
+const UnitVTable device_vtable = {
+ .suffix = ".device",
+
+ .no_requires = true,
+ .no_instances = true,
+ .no_snapshots = true,
+ .no_isolate = true,
+
+ .load = unit_load_fragment_and_dropin_optional,
+ .done = device_done,
+ .coldplug = device_coldplug,
+
+ .dump = device_dump,
+
+ .active_state = device_active_state,
+ .sub_state_to_string = device_sub_state_to_string,
+
+ .bus_message_handler = bus_device_message_handler,
+
+ .enumerate = device_enumerate,
+ .shutdown = device_shutdown
+};