glibc/sysdeps/unix/sysv/linux/kstat_cp.h

/* Empty, it is overridden by an architecture which might require copy to or
   from a kernel_stat stat struct to glibc export stat{64}.  */
linux: Disentangle fstatat from fxstatat It implements all the required syscall for the all Linux kABIS on fstatat{64} instead of calling fxstatat{64}. On non-LFS implementation, it handles 3 cases: 1. New kABIs which uses generic pre 64-bit time Linux ABI (csky and nios): it issues __NR_fstat64 plus handle the overflow on st_ino, st_size, or st_blocks. 2. Old KABIs with old non-LFS support (arm, i386, hppa, m68k, microblaze, mips32, s390, sh, powerpc, and sparc32): it issues __NR_fstatat64 and convert the result to struct stat. 3. 64-bit kABI outliers (mips64 and mips64-n32): it issues __NR_newfstatat and convert the result to struct stat. The generic LFS implementation handles multiple cases: 1. XSTAT_IS_XSTAT64 being 1: 1.1. 64-bit kABI (aarch64, ia64, powerpc64*, s390x, riscv64, and x86_64): it issues __NR_newfstatat. 1.2. 64-bit kABI outlier (alpha): it issues __NR_fstatat64. 1.3. 64-bit kABI outlier where struct stat64 does not match kernel one (sparc64): it issues __NR_fstatat64 and convert the result to struct stat64. 1.4. 32-bit kABI with default 64-bit time_t (arc, riscv32): it issues __NR_statx and convert the result to struct stat64. 2. Old ABIs with XSTAT_IS_XSTAT64 being 0: 2.1. All kABIs with non-LFS support (arm, csky, i386, hppa, m68k, microblaze, nios2, sh, powerpc32, and sparc32): it issues __NR_fstatat64. 2.2. 64-bit kABI outliers (mips64 and mips64-n32): it issues __NR_newfstatat and convert the result to struct stat64. It allows to remove all the hidden definitions from the {f,l}xstat{64} (some are still kept because Hurd requires it). Checked with a build for all affected ABIs. I also checked on x86_64, i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x. Reviewed-by: Lukasz Majewski <lukma@denx.de> 2020-07-18 11:20:46 +00:00			`/* Empty, it is overridden by an architecture which might require copy to or`
			`from a kernel_stat stat struct to glibc export stat{64}. */`