Emulate sigaction() using sigvec()

diff --git a/sigaction.c b/sigaction.c
new file mode 100644 (file)
index 0000000..bfa06d4
--- /dev/null
+++ b/sigaction.c
@@ -0,0 +1,155 @@
+/*
+ * Copyright (c) 2001 Todd C. Miller <Todd.Miller@courtesan.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * 4. Products derived from this software may not be called "Sudo" nor
+ *    may "Sudo" appear in their names without specific prior written
+ *    permission from the author.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
+ * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <signal.h>
+#include <errno.h>
+
+#include <compat.h>
+
+#ifndef lint
+static const char rcsid[] = "$Sudo$";
+#endif /* lint */
+
+int
+sigaction(signo, sa, osa)
+    int signo;
+    const sigaction_t *sa;
+    sigaction_t *osa;
+{
+    sigaction_t nsa;
+    int error;
+
+    /* We must reverse SV_INTERRUPT since it is the opposite of SA_RESTART */
+    if (sa) {
+       nsa = *sa;
+       nsa.sa_flags ^= SV_INTERRUPT;
+       sa = &nsa;
+    }
+
+    error = sigvec(signo, sa, osa)
+    if (!error && osa)
+       osa->sa_flags ^= SV_INTERRUPT;          /* flip SV_INTERRUPT as above */
+
+    return(error);
+}
+
+int
+sigemptyset(set)
+    sigset_t *set;
+{
+
+    *set = 0;
+    return(0);
+}
+
+int
+sigfillset(set)
+    sigset_t *set;
+{
+
+    *set = ~0;;
+    return(0);
+}
+
+int
+sigaddset(set, signo)
+    sigset_t *set;
+    int signo;
+{
+
+    if (signo <= 0 || signo >= NSIG) {
+       errno = EINVAL;
+       return(-1);
+    }
+
+    *set |= sigmask(signo);
+    return(0);
+}
+
+int
+sigdelset(set, signo)
+    sigset_t *set;
+    int signo;
+{
+
+    if (signo <= 0 || signo >= NSIG) {
+       errno = EINVAL;
+       return(-1);
+    }
+
+    *set &= ~(sigmask(signo));
+    return(0);
+}
+
+int
+sigismember(set, signo)
+    sigset_t *set;
+    int signo;
+{
+
+    return(*set & sigmask(signo));
+}
+
+int
+sigprocmask(how, set, oset)
+    int how;
+    const sigset_t *set;
+    sigset_t *oset;
+{
+    int mask;
+
+    /* If 'set' is NULL the user just wants the current signal mask. */
+    if (set == NULL)
+       mask = sigblock(0);
+    else
+       switch (how) {
+           case SIG_BLOCK:
+               mask = sigblock(*set);
+               break;
+           case SIG_UNBLOCK:
+               mask = sigsetmask(~*set);
+               break;
+           case SIG_SETMASK:
+               mask = sigsetmask(*set);
+               break;
+           default:
+               return(-1);
+       }
+
+    if (mask == -1)
+       return(-1);
+    if (oset)
+       *oset = mask;
+    return(0);
+}