Systemd/src/udev/udevadm-util.c

50 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
#include <errno.h>
#include "alloc-util.h"
#include "device-private.h"
#include "path-util.h"
#include "udevadm-util.h"
#include "unit-name.h"
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. */
if (unit_name_is_valid(id, UNIT_NAME_PLAIN) &&
unit_name_to_type(id) == UNIT_DEVICE) {
r = unit_name_to_path(id, &path);
if (r < 0)
return log_debug_errno(r, "Failed to convert \"%s\" to a device path: %m", id);
id = path;
}
}
if (path_startswith(id, "/sys/"))
return sd_device_new_from_syspath(ret, id);
if (path_startswith(id, "/dev/")) {
struct stat st;
if (stat(id, &st) < 0)
return -errno;
return device_new_from_stat_rdev(ret, &st);
}
return -EINVAL;
}