summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorRich Felker <dalias@aerifal.cx>2019-07-18 21:46:33 -0400
committerRich Felker <dalias@aerifal.cx>2019-07-18 21:46:33 -0400
commitdfc81828f7ab41da08f744c44117a1bb20a05749 (patch)
tree98f334767e4e146b96ba40dc5f094528003a18e9
parent67bf602f14249ff1757c54f071faa3f778279c02 (diff)
downloadmusl-dfc81828f7ab41da08f744c44117a1bb20a05749.tar.gz
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.
-rw-r--r--src/stat/fstatat.c70
1 files changed, 68 insertions, 2 deletions
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 <string.h>
#include <fcntl.h>
#include <errno.h>
+#include <stdint.h>
+#include <sys/sysmacros.h>
#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);