Add sigtimedwait and sigprocmask wrappers

The existing sigprocmask wrappers are consolidated into a single
definition using rt_sigprocmask and no longer checks for ENOSYS.
These system calls should exist on Linux 2.2+. Support for older
kernels will require callers to handle ENOSYS themselves.

Bug: crashpad:265
Change-Id: I25bc8c811c2f93aa20ff64fe3bacdcd017ff10c6
Reviewed-on: https://chromium-review.googlesource.com/c/linux-syscall-support/+/1914504
Reviewed-by: Mike Frysinger <vapier@chromium.org>
diff --git a/linux_syscall_support.h b/linux_syscall_support.h
index 9276f56..8e0cc38 100644
--- a/linux_syscall_support.h
+++ b/linux_syscall_support.h
@@ -3509,6 +3509,8 @@
                        struct kernel_sigset_t*,        o, size_t, c)
   LSS_INLINE _syscall2(int, rt_sigsuspend,
                        const struct kernel_sigset_t*, s,  size_t, c)
+  LSS_INLINE _syscall4(int, rt_sigtimedwait, const struct kernel_sigset_t*, s,
+                       siginfo_t*, i, const struct timespec*, t, size_t, c)
   LSS_INLINE _syscall3(int,     sched_getaffinity,pid_t,      p,
                        unsigned int,   l, unsigned long *, m)
   LSS_INLINE _syscall3(int,     sched_setaffinity,pid_t,      p,
@@ -3704,14 +3706,22 @@
       return LSS_NAME(rt_sigpending)(set, (KERNEL_NSIG+7)/8);
     }
 
+    LSS_INLINE int LSS_NAME(sigsuspend)(const struct kernel_sigset_t *set) {
+      return LSS_NAME(rt_sigsuspend)(set, (KERNEL_NSIG+7)/8);
+    }
+  #endif
+  #if defined(__NR_rt_sigprocmask)
     LSS_INLINE int LSS_NAME(sigprocmask)(int how,
                                          const struct kernel_sigset_t *set,
                                          struct kernel_sigset_t *oldset) {
       return LSS_NAME(rt_sigprocmask)(how, set, oldset, (KERNEL_NSIG+7)/8);
     }
-
-    LSS_INLINE int LSS_NAME(sigsuspend)(const struct kernel_sigset_t *set) {
-      return LSS_NAME(rt_sigsuspend)(set, (KERNEL_NSIG+7)/8);
+  #endif
+  #if defined(__NR_rt_sigtimedwait)
+    LSS_INLINE int LSS_NAME(sigtimedwait)(const struct kernel_sigset_t *set,
+                                          siginfo_t *info,
+                                          const struct timespec *timeout) {
+      return LSS_NAME(rt_sigtimedwait)(set, info, timeout, (KERNEL_NSIG+7)/8);
     }
   #endif
   #if defined(__NR_wait4)
@@ -3887,7 +3897,6 @@
      (defined(__s390__) && !defined(__s390x__))
     #define __NR__sigaction   __NR_sigaction
     #define __NR__sigpending  __NR_sigpending
-    #define __NR__sigprocmask __NR_sigprocmask
     #define __NR__sigsuspend  __NR_sigsuspend
     #define __NR__socketcall  __NR_socketcall
     LSS_INLINE _syscall2(int, fstat64,             int, f,
@@ -3916,9 +3925,6 @@
                          const struct kernel_old_sigaction*,  a,
                          struct kernel_old_sigaction*,        o)
     LSS_INLINE _syscall1(int,   _sigpending, unsigned long*, s)
-    LSS_INLINE _syscall3(int,   _sigprocmask,      int,   h,
-                         const unsigned long*,     s,
-                         unsigned long*,           o)
     #ifdef __PPC__
     LSS_INLINE _syscall1(int, _sigsuspend,         unsigned long, s)
     #else
@@ -4002,23 +4008,6 @@
       return rc;
     }
 
-    LSS_INLINE int LSS_NAME(sigprocmask)(int how,
-                                         const struct kernel_sigset_t *set,
-                                         struct kernel_sigset_t *oldset) {
-      int olderrno = LSS_ERRNO;
-      int rc = LSS_NAME(rt_sigprocmask)(how, set, oldset, (KERNEL_NSIG+7)/8);
-      if (rc < 0 && LSS_ERRNO == ENOSYS) {
-        LSS_ERRNO = olderrno;
-        if (oldset) {
-          LSS_NAME(sigemptyset)(oldset);
-        }
-        rc = LSS_NAME(_sigprocmask)(how,
-                                    set ? &set->sig[0] : NULL,
-                                    oldset ? &oldset->sig[0] : NULL);
-      }
-      return rc;
-    }
-
     LSS_INLINE int LSS_NAME(sigsuspend)(const struct kernel_sigset_t *set) {
       int olderrno = LSS_ERRNO;
       int rc = LSS_NAME(rt_sigsuspend)(set, (KERNEL_NSIG+7)/8);