| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| |
| #include <errno.h> |
| |
| #include "alloc-util.h" |
| #include "bus-error.h" |
| #include "bus-util.h" |
| #include "device-private.h" |
| #include "path-util.h" |
| #include "udevadm-util.h" |
| #include "unit-name.h" |
| |
| static int find_device_from_path(const char *path, sd_device **ret) { |
| if (path_startswith(path, "/sys/")) |
| return sd_device_new_from_syspath(ret, path); |
| |
| if (path_startswith(path, "/dev/")) { |
| struct stat st; |
| |
| if (stat(path, &st) < 0) |
| return -errno; |
| |
| return sd_device_new_from_stat_rdev(ret, &st); |
| } |
| |
| return -EINVAL; |
| } |
| |
| static int find_device_from_unit(const char *unit_name, sd_device **ret) { |
| _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; |
| _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; |
| _cleanup_free_ char *unit_path = NULL, *syspath = NULL; |
| int r; |
| |
| if (!unit_name_is_valid(unit_name, UNIT_NAME_PLAIN)) |
| return -EINVAL; |
| |
| if (unit_name_to_type(unit_name) != UNIT_DEVICE) |
| return -EINVAL; |
| |
| r = bus_connect_system_systemd(&bus); |
| if (r < 0) { |
| _cleanup_free_ char *path = NULL; |
| |
| log_debug_errno(r, "Failed to open connection to systemd, using unit name as syspath: %m"); |
| |
| r = unit_name_to_path(unit_name, &path); |
| if (r < 0) |
| return log_debug_errno(r, "Failed to convert \"%s\" to a device path: %m", unit_name); |
| |
| return find_device_from_path(path, ret); |
| } |
| |
| unit_path = unit_dbus_path_from_name(unit_name); |
| if (!unit_path) |
| return -ENOMEM; |
| |
| r = sd_bus_get_property_string( |
| bus, |
| "org.freedesktop.systemd1", |
| unit_path, |
| "org.freedesktop.systemd1.Device", |
| "SysFSPath", |
| &error, |
| &syspath); |
| if (r < 0) |
| return log_debug_errno(r, "Failed to get SysFSPath= dbus property for %s: %s", |
| unit_name, bus_error_message(&error, r)); |
| |
| return sd_device_new_from_syspath(ret, syspath); |
| } |
| |
| int find_device(const char *id, const char *prefix, sd_device **ret) { |
| _cleanup_free_ char *path = NULL; |
| int r; |
| |
| assert(id); |
| assert(ret); |
| |
| if (prefix) { |
| if (!path_startswith(id, prefix)) { |
| id = path = path_join(prefix, id); |
| if (!path) |
| return -ENOMEM; |
| } |
| } else { |
| /* In cases where the argument is generic (no prefix specified), |
| * check if the argument looks like a device unit name. */ |
| r = find_device_from_unit(id, ret); |
| if (r >= 0) |
| return r; |
| } |
| |
| return find_device_from_path(id, ret); |
| } |