nptl: SIGCANCEL, SIGTIMER, SIGSETXID are always defined

All nptl targets have these signal definitions nowadays.  This
changes also replaces the nptl-generic version of pthread_sigmask
with the Linux version.

Tested on x86_64-linux-gnu and i686-linux-gnu.  Built with
build-many-glibcs.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

8 files changed, 29 insertions, 50 deletions

diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
index 64a9ae6066..086efb75ec 100644
--- a/nptl/allocatestack.c
+++ b/nptl/allocatestack.c
@@ -963,7 +963,6 @@ __reclaim_stacks (void)
 }
 
 
-#ifdef SIGSETXID
 static void
 setxid_mark_thread (struct xid_command *cmdp, struct pthread *t)
 {
@@ -1174,8 +1173,6 @@ __nptl_setxid (struct xid_command *cmdp)
   lll_unlock (stack_cache_lock, LLL_PRIVATE);
   return result;
 }
-#endif  /* SIGSETXID.  */
-
 
 static inline void __attribute__((always_inline))
 init_one_static_tls (struct pthread *curp, struct link_map *map)
diff --git a/nptl/nptl-init.c b/nptl/nptl-init.c
index ea91b9e138..acc0f3672b 100644
--- a/nptl/nptl-init.c
+++ b/nptl/nptl-init.c
@@ -114,9 +114,7 @@ static const struct pthread_functions pthread_functions =
     .ptr_nthreads = &__nptl_nthreads,
     .ptr___pthread_unwind = &__pthread_unwind,
     .ptr__nptl_deallocate_tsd = __nptl_deallocate_tsd,
-# ifdef SIGSETXID
     .ptr__nptl_setxid = __nptl_setxid,
-# endif
     .ptr_set_robust = __nptl_set_robust
   };
 # define ptr_pthread_functions &pthread_functions
@@ -139,7 +137,6 @@ __nptl_set_robust (struct pthread *self)
 }
 
 
-#ifdef SIGCANCEL
 /* For asynchronous cancellation we use a signal.  This is the handler.  */
 static void
 sigcancel_handler (int sig, siginfo_t *si, void *ctx)
@@ -185,10 +182,8 @@ sigcancel_handler (int sig, siginfo_t *si, void *ctx)
       oldval = curval;
     }
 }
-#endif
 
 
-#ifdef SIGSETXID
 struct xid_command *__xidcmd attribute_hidden;
 
 /* We use the SIGSETXID signal in the setuid, setgid, etc. implementations to
@@ -234,7 +229,6 @@ sighandler_setxid (int sig, siginfo_t *si, void *ctx)
   if (atomic_decrement_val (&__xidcmd->cntr) == 0)
     futex_wake ((unsigned int *) &__xidcmd->cntr, 1, FUTEX_PRIVATE);
 }
-#endif
 
 
 /* When using __thread for this, we do it in libc so as not
@@ -285,41 +279,31 @@ __pthread_initialize_minimal_internal (void)
      had to set __nptl_initial_report_events.  Propagate its setting.  */
   THREAD_SETMEM (pd, report_events, __nptl_initial_report_events);
 
-#if defined SIGCANCEL || defined SIGSETXID
   struct sigaction sa;
   __sigemptyset (&sa.sa_mask);
 
-# ifdef SIGCANCEL
   /* Install the cancellation signal handler.  If for some reason we
      cannot install the handler we do not abort.  Maybe we should, but
      it is only asynchronous cancellation which is affected.  */
   sa.sa_sigaction = sigcancel_handler;
   sa.sa_flags = SA_SIGINFO;
   (void) __libc_sigaction (SIGCANCEL, &sa, NULL);
-# endif
 
-# ifdef SIGSETXID
   /* Install the handle to change the threads' uid/gid.  */
   sa.sa_sigaction = sighandler_setxid;
   sa.sa_flags = SA_SIGINFO | SA_RESTART;
   (void) __libc_sigaction (SIGSETXID, &sa, NULL);
-# endif
 
   /* The parent process might have left the signals blocked.  Just in
      case, unblock it.  We reuse the signal mask in the sigaction
      structure.  It is already cleared.  */
-# ifdef SIGCANCEL
   __sigaddset (&sa.sa_mask, SIGCANCEL);
-# endif
-# ifdef SIGSETXID
   __sigaddset (&sa.sa_mask, SIGSETXID);
-# endif
   {
     INTERNAL_SYSCALL_DECL (err);
     (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &sa.sa_mask,
 			     NULL, _NSIG / 8);
   }
-#endif
 
   /* Get the size of the static and alignment requirements for the TLS
      block.  */
diff --git a/nptl/pthread_cancel.c b/nptl/pthread_cancel.c
index 64ac12e60a..f6be8c1dd6 100644
--- a/nptl/pthread_cancel.c
+++ b/nptl/pthread_cancel.c
@@ -63,7 +63,6 @@ __pthread_cancel (pthread_t th)
 						    oldval))
 	    goto again;
 
-#ifdef SIGCANCEL
 	  /* The cancellation handler will take care of marking the
 	     thread as canceled.  */
 	  pid_t pid = __getpid ();
@@ -73,12 +72,6 @@ __pthread_cancel (pthread_t th)
 					   SIGCANCEL);
 	  if (INTERNAL_SYSCALL_ERROR_P (val, err))
 	    result = INTERNAL_SYSCALL_ERRNO (val, err);
-#else
-          /* It should be impossible to get here at all, since
-             pthread_setcanceltype should never have allowed
-             PTHREAD_CANCEL_ASYNCHRONOUS to be set.  */
-          abort ();
-#endif
 
 	  break;
 	}
diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c
index 130937c3c4..5682c9c2c0 100644
--- a/nptl/pthread_create.c
+++ b/nptl/pthread_create.c
@@ -402,7 +402,6 @@ START_THREAD_DEFN
     }
 #endif
 
-#ifdef SIGCANCEL
   /* If the parent was running cancellation handlers while creating
      the thread the new thread inherited the signal mask.  Reset the
      cancellation signal mask.  */
@@ -415,7 +414,6 @@ START_THREAD_DEFN
       (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &mask,
 			       NULL, _NSIG / 8);
     }
-#endif
 
   /* This is where the try/finally block should be created.  For
      compilers without that support we do use setjmp.  */
diff --git a/nptl/pthread_setcanceltype.c b/nptl/pthread_setcanceltype.c
index d771c31e46..99bc13e993 100644
--- a/nptl/pthread_setcanceltype.c
+++ b/nptl/pthread_setcanceltype.c
@@ -27,11 +27,6 @@ __pthread_setcanceltype (int type, int *oldtype)
   if (type < PTHREAD_CANCEL_DEFERRED || type > PTHREAD_CANCEL_ASYNCHRONOUS)
     return EINVAL;
 
-#ifndef SIGCANCEL
-  if (type == PTHREAD_CANCEL_ASYNCHRONOUS)
-    return ENOTSUP;
-#endif
-
   volatile struct pthread *self = THREAD_SELF;
 
   int oldval = THREAD_GETMEM (self, cancelhandling);
diff --git a/nptl/pthread_sigmask.c b/nptl/pthread_sigmask.c
index c8df527995..4aa774d01d 100644
--- a/nptl/pthread_sigmask.c
+++ b/nptl/pthread_sigmask.c
@@ -1,6 +1,6 @@
-/* Examine and change blocked signals for a thread.  Generic POSIX version.
-   Copyright (C) 2014-2019 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2019 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
    The GNU C Library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
@@ -19,18 +19,36 @@
 #include <errno.h>
 #include <signal.h>
 #include <pthreadP.h>
+#include <sysdep.h>
 
-#if defined SIGCANCEL || defined SIGTIMER || defined SIGSETXID
-# error "This implementation assumes no internal-only signal numbers."
-#endif
 
 int
 pthread_sigmask (int how, const sigset_t *newmask, sigset_t *oldmask)
 {
-  /* Here we assume that sigprocmask actually does everything right.
-     The only difference is the return value protocol.  */
-  int result = sigprocmask (how, newmask, oldmask);
-  if (result < 0)
-    result = errno;
-  return result;
+  sigset_t local_newmask;
+
+  /* The only thing we have to make sure here is that SIGCANCEL and
+     SIGSETXID is not blocked.  */
+  if (newmask != NULL
+      && (__builtin_expect (__sigismember (newmask, SIGCANCEL), 0)
+	  || __builtin_expect (__sigismember (newmask, SIGSETXID), 0)))
+    {
+      local_newmask = *newmask;
+      __sigdelset (&local_newmask, SIGCANCEL);
+      __sigdelset (&local_newmask, SIGSETXID);
+      newmask = &local_newmask;
+    }
+
+#ifdef INTERNAL_SYSCALL
+  /* We know that realtime signals are available if NPTL is used.  */
+  INTERNAL_SYSCALL_DECL (err);
+  int result = INTERNAL_SYSCALL (rt_sigprocmask, err, 4, how, newmask,
+				 oldmask, _NSIG / 8);
+
+  return (INTERNAL_SYSCALL_ERROR_P (result, err)
+	  ? INTERNAL_SYSCALL_ERRNO (result, err)
+	  : 0);
+#else
+  return sigprocmask (how, newmask, oldmask) == -1 ? errno : 0;
+#endif
 }
diff --git a/nptl/tst-cancel25.c b/nptl/tst-cancel25.c
index 24ddd3c01c..c6e1c23c02 100644
--- a/nptl/tst-cancel25.c
+++ b/nptl/tst-cancel25.c
@@ -12,7 +12,6 @@ static pthread_t th2;
 static void *
 tf2 (void *arg)
 {
-#ifdef SIGCANCEL
   sigset_t mask;
   if (pthread_sigmask (SIG_SETMASK, NULL, &mask) != 0)
     {
@@ -24,7 +23,6 @@ tf2 (void *arg)
       puts ("SIGCANCEL blocked in new thread");
       exit (1);
     }
-#endif
 
   /* Sync with the main thread so that we do not test anything else.  */
   int e = pthread_barrier_wait (&b);
diff --git a/nptl/tst-signal7.c b/nptl/tst-signal7.c
index de67ab493c..f42ff6887a 100644
--- a/nptl/tst-signal7.c
+++ b/nptl/tst-signal7.c
@@ -27,7 +27,6 @@ do_test (void)
 {
   int result = 0;
 
-#ifdef SIGCANCEL
   errno = 0;
   if (sigaction (SIGCANCEL, NULL, NULL) == 0)
     {
@@ -39,9 +38,7 @@ do_test (void)
       puts ("sigaction(SIGCANCEL) did not set errno to EINVAL");
       result = 1;
     }
-#endif
 
-#ifdef SIGSETXID
   errno = 0;
   if (sigaction (SIGSETXID, NULL, NULL) == 0)
     {
@@ -53,7 +50,6 @@ do_test (void)
       puts ("sigaction(SIGSETXID) did not set errno to EINVAL");
       result = 1;
     }
-#endif
 
   return result;
 }