From dfc81828f7ab41da08f744c44117a1bb20a05749 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Thu, 18 Jul 2019 21:46:33 -0400 Subject: implement fstatat with SYS_statx, conditional on undersized kstat time this commit adds a new backend for fstatat (and thereby the whole stat family) using the SYS_statx syscall, but conditions the new code on the kernel stat structure's time fields being smaller than time_t. in principle that should make it all dead code at present, but mips64 has a broken stat structure with 32-bit time fields despite having 64-bit time_t elsewhere, so on mips64 it is a functional change that makes post-Y2038 filesystem timestamps accessible. whenever the 32-bit archs end up getting 64-bit time_t, regardless of how that happens, the changes in this commit will automatically take effect for them too. --- src/stat/fstatat.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 68 insertions(+), 2 deletions(-) (limited to 'src/stat') diff --git a/src/stat/fstatat.c b/src/stat/fstatat.c index 29d63343..31907e98 100644 --- a/src/stat/fstatat.c +++ b/src/stat/fstatat.c @@ -3,10 +3,65 @@ #include #include #include +#include +#include #include "syscall.h" #include "kstat.h" -int fstatat(int fd, const char *restrict path, struct stat *restrict st, int flag) +struct statx { + uint32_t stx_mask; + uint32_t stx_blksize; + uint64_t stx_attributes; + uint32_t stx_nlink; + uint32_t stx_uid; + uint32_t stx_gid; + uint16_t stx_mode; + uint16_t pad1; + uint64_t stx_ino; + uint64_t stx_size; + uint64_t stx_blocks; + uint64_t stx_attributes_mask; + struct { + int64_t tv_sec; + uint32_t tv_nsec; + int32_t pad; + } stx_atime, stx_btime, stx_ctime, stx_mtime; + uint32_t stx_rdev_major; + uint32_t stx_rdev_minor; + uint32_t stx_dev_major; + uint32_t stx_dev_minor; + uint64_t spare[14]; +} stx; + +static int fstatat_statx(int fd, const char *restrict path, struct stat *restrict st, int flag) +{ + struct statx stx; + + int ret = __syscall(SYS_statx, fd, path, flag, 0x7ff, &stx); + if (ret) return ret; + + *st = (struct stat){ + .st_dev = makedev(stx.stx_dev_major, stx.stx_dev_minor), + .st_ino = stx.stx_ino, + .st_mode = stx.stx_mode, + .st_nlink = stx.stx_nlink, + .st_uid = stx.stx_uid, + .st_gid = stx.stx_gid, + .st_rdev = makedev(stx.stx_rdev_major, stx.stx_rdev_minor), + .st_size = stx.stx_size, + .st_blksize = stx.stx_blksize, + .st_blocks = stx.stx_blocks, + .st_atim.tv_sec = stx.stx_atime.tv_sec, + .st_atim.tv_nsec = stx.stx_atime.tv_nsec, + .st_mtim.tv_sec = stx.stx_mtime.tv_sec, + .st_mtim.tv_nsec = stx.stx_mtime.tv_nsec, + .st_ctim.tv_sec = stx.stx_ctime.tv_sec, + .st_ctim.tv_nsec = stx.stx_ctime.tv_nsec, + }; + return 0; +} + +static int fstatat_kstat(int fd, const char *restrict path, struct stat *restrict st, int flag) { int ret; struct kstat kst; @@ -36,7 +91,7 @@ int fstatat(int fd, const char *restrict path, struct stat *restrict st, int fla #endif else ret = __syscall(SYS_fstatat, fd, path, &kst, flag); - if (ret) return __syscall_ret(ret); + if (ret) return ret; *st = (struct stat){ .st_dev = kst.st_dev, @@ -60,4 +115,15 @@ int fstatat(int fd, const char *restrict path, struct stat *restrict st, int fla return 0; } +int fstatat(int fd, const char *restrict path, struct stat *restrict st, int flag) +{ + int ret; + if (sizeof((struct kstat){0}.st_atime_sec) < sizeof(time_t)) { + ret = fstatat_statx(fd, path, st, flag); + if (ret!=-ENOSYS) return __syscall_ret(ret); + } + ret = fstatat_kstat(fd, path, st, flag); + return __syscall_ret(ret); +} + weak_alias(fstatat, fstatat64); -- cgit v1.2.1