4 files changed, 93 insertions, 4 deletions
diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
index 3a543ddf1cc45..9028043b532bb 100644
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -497,10 +497,13 @@ MLINKS+=setjmp.3 _longjmp.3 \
 MLINKS+=setmode.3 getmode.3
 MLINKS+=setproctitle.3 setproctitle_fast.3
 MLINKS+=sigsetops.3 sigaddset.3 \
+	sigsetops.3 sigandset.3 \
 	sigsetops.3 sigdelset.3 \
 	sigsetops.3 sigemptyset.3 \
 	sigsetops.3 sigfillset.3 \
-	sigsetops.3 sigismember.3
+	sigsetops.3 sigisemptyset.3 \
+	sigsetops.3 sigismember.3 \
+	sigsetops.3 sigorset.3
 MLINKS+=statvfs.3 fstatvfs.3
 MLINKS+=stringlist.3 sl_add.3 \
 	stringlist.3 sl_find.3 \
diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map
index 703cfe796a384..c6ecbc65f8494 100644
--- a/lib/libc/gen/Symbol.map
+++ b/lib/libc/gen/Symbol.map
@@ -422,6 +422,12 @@ FBSD_1.5 {
 	timespec_get;
 };
 
+FBSD_1.6 {
+	sigandset;
+	sigisemptyset;
+	sigorset;
+};
+
 FBSDprivate_1.0 {
 	/* needed by thread libraries */
 	__thr_jtable;
diff --git a/lib/libc/gen/sigsetops.3 b/lib/libc/gen/sigsetops.3
index 48c14106a4cc8..a184289aeb8a5 100644
--- a/lib/libc/gen/sigsetops.3
+++ b/lib/libc/gen/sigsetops.3
@@ -28,15 +28,18 @@
 .\"     @(#)sigsetops.3	8.1 (Berkeley) 6/4/93
 .\" $FreeBSD$
 .\"
-.Dd December 16, 2004
+.Dd October 29, 2019
 .Dt SIGSETOPS 3
 .Os
 .Sh NAME
 .Nm sigemptyset ,
 .Nm sigfillset ,
 .Nm sigaddset ,
+.Nm sigandset ,
 .Nm sigdelset ,
-.Nm sigismember
+.Nm sigisemptyset ,
+.Nm sigismember ,
+.Nm sigorset
 .Nd manipulate signal sets
 .Sh LIBRARY
 .Lb libc
@@ -49,9 +52,15 @@
 .Ft int
 .Fn sigaddset "sigset_t *set" "int signo"
 .Ft int
+.Fn sigandset "sigset_t *set" "const sigset_t *left" "const sigset_t *right"
+.Ft int
 .Fn sigdelset "sigset_t *set" "int signo"
 .Ft int
+.Fn sigisemptyset "const sigset_t *set"
+.Ft int
 .Fn sigismember "const sigset_t *set" "int signo"
+.Ft int
+.Fn sigorset "sigset_t *set" "const sigset_t *left" "const sigset_t *right"
 .Sh DESCRIPTION
 These functions manipulate signal sets stored in a
 .Fa sigset_t .
@@ -78,22 +87,54 @@ function adds the specified signal
 to the signal set.
 .Pp
 The
+.Fn sigandset
+function sets the specified
+.Fa set
+to the logical AND of all signals from the
+.Fa left
+and
+.Fa right
+signal sets.
+.Pp
+The
 .Fn sigdelset
 function deletes the specified signal
 .Fa signo
 from the signal set.
 .Pp
 The
+.Fn sigisemptyset
+function returns whether the specified
+.Fa set
+is empty or not.
+.Pp
+The
 .Fn sigismember
 function returns whether a specified signal
 .Fa signo
 is contained in the signal set.
+.Pp
+The
+.Fn sigorset
+function sets the specified
+.Fa set
+to the logical OR of all signals from the
+.Fa left
+and
+.Fa right
+signal sets.
 .Sh RETURN VALUES
 The
+.Fn sigisemptyset
+function returns 1
+if the set is empty, 0 otherwise.
+.Pp
+The
 .Fn sigismember
 function returns 1
 if the signal is a member of the set,
 0 otherwise.
+.Pp
 The other functions return 0 upon success.
 A \-1 return value
 indicates an error occurred and the global variable
@@ -113,5 +154,13 @@ has an invalid value.
 .Xr sigprocmask 2 ,
 .Xr sigsuspend 2
 .Sh STANDARDS
-These functions are defined by
+The
+.Fn sigandset ,
+.Fn sigisemptyset ,
+and
+.Fn sigorset
+functions are FreeBSD extensions, compatible with functions of the same name
+provided by both musl libc and GNU libc.
+.Pp
+The rest of these functions are defined by
 .St -p1003.1-88 .
diff --git a/lib/libc/gen/sigsetops.c b/lib/libc/gen/sigsetops.c
index 933bfa13ab01f..53a450c0e5f67 100644
--- a/lib/libc/gen/sigsetops.c
+++ b/lib/libc/gen/sigsetops.c
@@ -81,6 +81,37 @@ sigfillset(sigset_t *set)
 }
 
 int
+sigorset(sigset_t *dest, const sigset_t *left, const sigset_t *right)
+{
+	int i;
+
+	for (i = 0; i < _SIG_WORDS; i++)
+		dest->__bits[i] = left->__bits[i] | right->__bits[i];
+	return (0);
+}
+
+int
+sigandset(sigset_t *dest, const sigset_t *left, const sigset_t *right)
+{
+	int i;
+
+	for (i = 0; i < _SIG_WORDS; i++)
+		dest->__bits[i] = left->__bits[i] & right->__bits[i];
+	return (0);
+}
+
+int
+sigisemptyset(const sigset_t *set)
+{
+	int i;
+
+	for (i = 0; i < _SIG_WORDS; i++)
+		if (set->__bits[i] != 0)
+			return (0);
+	return (1);
+}
+
+int
 sigismember(const sigset_t *set, int signo)
 {