From 8f806bb1ea30f15db7ca36d1cfa79349f8115302 Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Thu, 6 Nov 2014 12:50:27 +0100 Subject: [PATCH] switch_root: improve statfs->f_type portability __SWORD_TYPE is not available everywhere, for example it's not defined by musl libc. It also seems that __SWORD_TYPE is not used for f_type on some architectures (s390x). Reported-by: Natanael Copa Signed-off-by: Karel Zak --- include/statfs_magic.h | 11 +++++++++++ sys-utils/switch_root.c | 4 ++-- 2 files changed, 13 insertions(+), 2 deletions(-) --- a/include/statfs_magic.h +++ b/include/statfs_magic.h @@ -1,6 +1,17 @@ #ifndef UTIL_LINUX_STATFS_MAGIC_H #define UTIL_LINUX_STATFS_MAGIC_H +#include + +/* + * If possible then don't depend on internal libc __SWORD_TYPE type. + */ +#ifdef __GNUC__ +typedef __typeof__( ((struct statfs *)0)->f_type ) ul_statfs_ftype_t; +#else +typedef __SWORD_TYPE ul_statfs_ftype_t; +#endif + /* * Unfortunately, Linux kernel hedeader file is incomplete * mess and kernel returns by statfs f_type many numbers that are nowhere --- a/sys-utils/switch_root.c +++ b/sys-utils/switch_root.c @@ -181,8 +181,8 @@ static int switchroot(const char *newroo if (pid <= 0) { struct statfs stfs; if (fstatfs(cfd, &stfs) == 0 && - (stfs.f_type == (__SWORD_TYPE)STATFS_RAMFS_MAGIC || - stfs.f_type == (__SWORD_TYPE)STATFS_TMPFS_MAGIC)) + (stfs.f_type == (ul_statfs_ftype_t) STATFS_RAMFS_MAGIC || + stfs.f_type == (ul_statfs_ftype_t) STATFS_TMPFS_MAGIC)) recursiveRemove(cfd); else warn(_("old root filesystem is not an initramfs"));