fix sigaltstack to ignore ss_size with SS_DISABLE, per POSIX

[android-x86/external-musl-libc.git] / src / signal / sigaltstack.c

diff --git a/src/signal/sigaltstack.c b/src/signal/sigaltstack.c
index 6e46d09..d3a6e82 100644 (file)
--- a/src/signal/sigaltstack.c
+++ b/src/signal/sigaltstack.c
@@ -2,17 +2,17 @@
 #include <errno.h>
 #include "syscall.h"
 
-int sigaltstack(const stack_t *ss, stack_t *old)
+int sigaltstack(const stack_t *restrict ss, stack_t *restrict old)
 {
        if (ss) {
-               if (ss->ss_size < MINSIGSTKSZ) {
+               if (!(ss->ss_flags & SS_DISABLE) && ss->ss_size < MINSIGSTKSZ) {
                        errno = ENOMEM;
                        return -1;
                }
-               if (ss->ss_flags & ~SS_DISABLE) {
+               if (ss->ss_flags & SS_ONSTACK) {
                        errno = EINVAL;
                        return -1;
                }
        }
-       return syscall2(__NR_sigaltstack, (long)ss, (long)old);
+       return syscall(SYS_sigaltstack, ss, old);
 }