add statx interface using syscall, fallback to fstatat

include/sys/stat.h

@@ -18,6 +18,13 @@ extern "C" {
 #define __NEED_blkcnt_t
 #define __NEED_struct_timespec
 
+#ifdef _GNU_SOURCE
+#define __NEED_int64_t
+#define __NEED_uint64_t
+#define __NEED_uint32_t
+#define __NEED_uint16_t
+#endif
+
 #include <bits/alltypes.h>
 
 #include <bits/stat.h>
@@ -98,6 +105,54 @@ int lchmod(const char *, mode_t);
 #define S_IEXEC S_IXUSR
 #endif
 
+#if defined(_GNU_SOURCE)
+#define STATX_TYPE 1U
+#define STATX_MODE 2U
+#define STATX_NLINK 4U
+#define STATX_UID 8U
+#define STATX_GID 0x10U
+#define STATX_ATIME 0x20U
+#define STATX_MTIME 0x40U
+#define STATX_CTIME 0x80U
+#define STATX_INO 0x100U
+#define STATX_SIZE 0x200U
+#define STATX_BLOCKS 0x400U
+#define STATX_BASIC_STATS 0x7ffU
+#define STATX_BTIME 0x800U
+#define STATX_ALL 0xfffU
+
+struct statx_timestamp {
+	int64_t tv_sec;
+	uint32_t tv_nsec, __pad;
+};
+
+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 __pad0[1];
+	uint64_t stx_ino;
+	uint64_t stx_size;
+	uint64_t stx_blocks;
+	uint64_t stx_attributes_mask;
+	struct statx_timestamp stx_atime;
+	struct statx_timestamp stx_btime;
+	struct statx_timestamp stx_ctime;
+	struct statx_timestamp stx_mtime;
+	uint32_t stx_rdev_major;
+	uint32_t stx_rdev_minor;
+	uint32_t stx_dev_major;
+	uint32_t stx_dev_minor;
+	uint64_t __pad1[14];
+};
+
+int statx(int, const char *__restrict, int, unsigned, struct statx *__restrict);
+#endif
+
 #if defined(_LARGEFILE64_SOURCE)
 #define stat64 stat
 #define fstat64 fstat

src/linux/statx.c

@@ -0,0 +1,42 @@
+#define _GNU_SOURCE
+#include <sys/stat.h>
+#include <string.h>
+#include <syscall.h>
+#include <sys/sysmacros.h>
+#include <errno.h>
+
+int statx(int dirfd, const char *restrict path, int flags, unsigned mask, struct statx *restrict stx)
+{
+	int ret = __syscall(SYS_statx, dirfd, path, flags, mask, stx);
+
+#ifndef SYS_fstatat
+	return __syscall_ret(ret);
+#endif
+
+	if (ret != -ENOSYS) return __syscall_ret(ret);
+
+	struct stat st;
+	ret = fstatat(dirfd, path, &st, flags);
+	if (ret) return ret;
+
+	stx->stx_dev_major = major(st.st_dev);
+	stx->stx_dev_minor = minor(st.st_dev);
+	stx->stx_ino = st.st_ino;
+	stx->stx_mode = st.st_mode;
+	stx->stx_nlink = st.st_nlink;
+	stx->stx_uid = st.st_uid;
+	stx->stx_gid = st.st_gid;
+	stx->stx_size = st.st_size;
+	stx->stx_blksize = st.st_blksize;
+	stx->stx_blocks = st.st_blocks;
+	stx->stx_atime.tv_sec = st.st_atim.tv_sec;
+	stx->stx_atime.tv_nsec = st.st_atim.tv_nsec;
+	stx->stx_mtime.tv_sec = st.st_mtim.tv_sec;
+	stx->stx_mtime.tv_nsec = st.st_mtim.tv_nsec;
+	stx->stx_ctime.tv_sec = st.st_ctim.tv_sec;
+	stx->stx_ctime.tv_nsec = st.st_ctim.tv_nsec;
+	stx->stx_btime = (struct statx_timestamp){.tv_sec=0, .tv_nsec=0};
+	stx->stx_mask = STATX_BASIC_STATS;
+
+	return 0;
+}