/* * Copyright (C) 2000-2006 Erik Andersen <andersen@uclibc.org> * * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. */ /* truncate64 syscall. Copes with 64 bit and 32 bit machines * and on 32 bit machines this sends things into the kernel as * two 32-bit arguments (high and low 32 bits of length) that * are ordered based on endianess. It turns out endian.h has * just the macro we need to order things, __LONG_LONG_PAIR. */ #include <features.h> #include <unistd.h> #include <errno.h> #include <endian.h> #include <stdint.h> #include <sys/types.h> #include <sys/syscall.h> #if defined __UCLIBC_HAS_LFS__ #if defined __NR_truncate64 #if __WORDSIZE == 64 /* For a 64 bit machine, life is simple... */ _syscall2(int, truncate64, const char *, path, __off64_t, length); #elif __WORDSIZE == 32 #ifndef INLINE_SYSCALL #define INLINE_SYSCALL(name, nr, args...) __syscall_truncate64 (args) #define __NR___syscall_truncate64 __NR_truncate64 #if defined(__UCLIBC_TRUNCATE64_HAS_4_ARGS__) static __inline__ _syscall4(int, __syscall_truncate64, const char *, path, uint32_t, pad, unsigned long, high_length, unsigned long, low_length); #else static __inline__ _syscall3(int, __syscall_truncate64, const char *, path, unsigned long, high_length, unsigned long, low_length); #endif #endif /* The exported truncate64 function. */ int truncate64 (const char * path, __off64_t length) { uint32_t low = length & 0xffffffff; uint32_t high = length >> 32; #if defined(__UCLIBC_TRUNCATE64_HAS_4_ARGS__) return INLINE_SYSCALL(truncate64, 4, path, 0, __LONG_LONG_PAIR (high, low)); #else return INLINE_SYSCALL(truncate64, 3, path, __LONG_LONG_PAIR (high, low)); #endif } #else /* __WORDSIZE */ #error Your machine is not 64 bit nor 32 bit, I am dazed and confused. #endif /* __WORDSIZE */ #else /* __NR_truncate64 */ libc_hidden_proto(truncate) int truncate64 (const char * path, __off64_t length) { __off_t x = (__off_t) length; if (x == length) { return truncate(path, x); } __set_errno((x < 0) ? EINVAL : EFBIG); return -1; } #endif /* __NR_truncate64 */ #endif /* __UCLIBC_HAS_LFS__ */