diff options
Diffstat (limited to 'libc/sysdeps/linux/common/truncate64.c')
-rw-r--r-- | libc/sysdeps/linux/common/truncate64.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/common/truncate64.c b/libc/sysdeps/linux/common/truncate64.c new file mode 100644 index 000000000..8c7d8bb5a --- /dev/null +++ b/libc/sysdeps/linux/common/truncate64.c @@ -0,0 +1,39 @@ +/* + * 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). + * + * Copyright (C) 2002 Erik Andersen <andersen@codepoet.org> + * + * This file is subject to the terms and conditions of the GNU + * Lesser General Public License. See the file COPYING.LIB in + * the main directory of this archive for more details. + */ + +#include <features.h> +#include <unistd.h> +#include <errno.h> +#include <endian.h> +#include <stdint.h> +#include <sys/syscall.h> + +#if defined __UCLIBC_HAVE_LFS__ && 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 +#define __NR___truncate64 __NR_truncate64 +static inline _syscall3(int, __truncate64, const char *, path, int, high_length, int, low_length); +/* The exported truncate64 function. */ +int truncate64 (const char * path, __off64_t length) +{ + unsigned int low = length & 0xffffffff; + unsigned int high = length >> 32; + return __truncate64(path, __LONG_LONG_PAIR (high, low)); +} +#else +#error Your machine is not 64 bit or 32 bit, I am dazed and confused. +#endif +#endif /* __UCLIBC_HAVE_LFS__ */ |