Commit 95c09828 authored by Richard Henderson's avatar Richard Henderson
Browse files

alpha-linux-user: Fix the getpriority syscall 



Alpha uses unbiased priority values in the syscall, with the a3
return value signaling error conditions.  Therefore, properly
interpret the libc getpriority as needed for the guest rather
than passing the host value through unchanged.

Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
parent 0229f5a3

linux-user/syscall.c

+15 −5
Original line number Diff line number Diff line
@@ -218,7 +218,6 @@ _syscall3(int, sys_getdents, uint, fd, struct linux_dirent *, dirp, uint, count) 
#if defined(TARGET_NR_getdents64) && defined(__NR_getdents64)

_syscall3(int, sys_getdents64, uint, fd, struct linux_dirent64 *, dirp, uint, count);

#endif

_syscall2(int, sys_getpriority, int, which, int, who);

#if defined(TARGET_NR__llseek) && defined(__NR_llseek)

_syscall5(int, _llseek,  uint,  fd, ulong, hi, ulong, lo,

          loff_t *, res, uint, wh);
@@ -6445,10 +6444,21 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, 
        break;

#endif

    case TARGET_NR_getpriority:

        /* libc does special remapping of the return value of

         * sys_getpriority() so it's just easiest to call

         * sys_getpriority() directly rather than through libc. */

        ret = get_errno(sys_getpriority(arg1, arg2));

        /* Note that negative values are valid for getpriority, so we must

           differentiate based on errno settings.  */

        errno = 0;

        ret = getpriority(arg1, arg2);

        if (ret == -1 && errno != 0) {

            ret = -host_to_target_errno(errno);

            break;

        }

#ifdef TARGET_ALPHA

        /* Return value is the unbiased priority.  Signal no error.  */

        ((CPUAlphaState *)cpu_env)->ir[IR_V0] = 0;

#else

        /* Return value is a biased priority to avoid negative numbers.  */

        ret = 20 - ret;

#endif

        break;

    case TARGET_NR_setpriority:

        ret = get_errno(setpriority(arg1, arg2, arg3));