efivar-0.21 fails to create boot entry when device min number > 127

[ssten]

No need to reproduce I guess, just see into linux.c:62:

set_disk_and_part_name(struct disk_info *info)
…
rc = sysfs_readlink(&linkbuf, "/sys/dev/block/%"PRIu64":%hhd",
info->major, info->minor);

%hhd prints unsigned info->minor as signed, which causes wrong device path if info->minor is greater than 127:

lsblk | grep sdj

sdj 8:144 1 29.8G 0 disk
├─sdj1 8:145 1 1G 0 part /boot
└─sdj2 8:146 1 28.8G 0 part /

strace efibootmgr -c -d /dev/sdj -p 1 -L … -l … -u … :
open("/dev/sdj", O_RDONLY) = 3
fstat(3, {st_mode=S_IFBLK|0660, st_rdev=makedev(8, 144), ...}) = 0
readlink("/sys/dev/block/8:-112", 0x7ffd5a0f9080, 4096) = -1 ENOENT

simple patch:

--- src/linux.c.old 2015-08-24 16:34:13.606782416 +0600
+++ src/linux.c 2015-08-24 16:34:21.366845626 +0600
@@ -59,7 +59,7 @@
char *linkbuf;
ssize_t rc;

- rc = sysfs_readlink(&linkbuf, "/sys/dev/block/%"PRIu64":%hhd",

•   rc = sysfs_readlink(&linkbuf, "/sys/dev/block/%"PRIu64":%hhu",
                  info->major, info->minor);
    if (rc < 0)
            return -1;