Provide IRT process interface

src/untrusted/nacl/sigprocmask.c

Index: src/untrusted/nacl/sigprocmask.c
diff --git a/src/untrusted/nacl/access.c b/src/untrusted/nacl/sigprocmask.c
similarity index 54%
copy from src/untrusted/nacl/access.c
copy to src/untrusted/nacl/sigprocmask.c
index 2469613350cfd15e8f921ebd121e5cb87a2962b6..fb6d62a780e4017a01fa5186ea2fb9bee00849a6 100644
--- a/src/untrusted/nacl/access.c
+++ b/src/untrusted/nacl/sigprocmask.c
@@ -5,17 +5,17 @@
  */
 
 #include <errno.h>
-#include <unistd.h>
+#include <signal.h>
 
 #include "native_client/src/untrusted/nacl/nacl_irt.h"
 
-int access(const char *pathname, int mode) {
-  if (!__libnacl_irt_init_fn(&__libnacl_irt_dev_filename.access,
-                             __libnacl_irt_dev_filename_init)) {
+int sigprocmask(int how, const sigset_t *set, sigset_t *oldset) {
+  if (!__libnacl_irt_init_fn(&__libnacl_irt_dev_process.sigprocmask,
+                             __libnacl_irt_dev_process_init)) {
     return -1;
   }
 
-  int error = __libnacl_irt_dev_filename.access(pathname, mode);
+  int error = __libnacl_irt_dev_process.sigprocmask(how, set, oldset);
   if (error) {
     errno = error;
     return -1;