According to official standard POSIX.1-2001. pread64 and pwrite64 should return 0 for zero-length buffers as mentioned at
http://pubs.opengroup.org/onlinepubs/009695399/functions/read.html http://pubs.opengroup.org/onlinepubs/009695399/functions/write.html Change-Id: Icd66ea29658329fbd5e6461d1def0c78c81d2671 Signed-off-by: Ilya Palachev <i.palac...@samsung.com> --- linux-user/syscall.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index a41dd43..a08f5ef 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -8127,6 +8127,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_ulong arg1, arg4 = arg5; arg5 = arg6; } + if (!arg3) { + ret = 0; + break; + } if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0))) goto efault; ret = get_errno(pread64(arg1, p, arg3, target_offset64(arg4, arg5))); @@ -8137,6 +8141,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_ulong arg1, arg4 = arg5; arg5 = arg6; } + if (!arg3) { + ret = 0; + break; + } if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1))) goto efault; ret = get_errno(pwrite64(arg1, p, arg3, target_offset64(arg4, arg5))); -- 2.1.3
