add documentation

1 files changed, 24 insertions, 2 deletions

diff --git a/src/setjmp/sigsetjmp.c b/src/setjmp/sigsetjmp.c
index 37c9727f..46eebeba 100644
--- a/src/setjmp/sigsetjmp.c
+++ b/src/setjmp/sigsetjmp.c
@@ -1,10 +1,32 @@
 #include <setjmp.h>
+#include "signal.h"
+
+/** save program state with signal mask **/
 
 int sigsetjmp(sigjmp_buf env, int savemask)
 {
-	(void)env; (void)savemask;
-	return 0;
+	if (savemask) {
+		/* save mask to env */
+	}
+	return setjmp(env);
 }
+
+/***
+saves the current state of the calling environment in the
+TYPEDEF(sigjmp_buf) ARGUMENT(env). If ARGUMENT(savemask) is nonzero, the saved
+environment includes the signal mask of the current thread.
+***/
+
 /*
+CONSTRAINT: entire controlling expression of a selection or iteration statement
+CONSTRAINT: one operand of a relational or equality operator which is the entire controlling expression of a selction or iteration statement
+CONSTRAINT: the operand of a unary ! as the entire controlling expression of a selection or iteration statement
+CONSTRAINT: an entire expression statement
+
+UNSPECIFIED(Whether THIS() is a macro or identifier with external linkage)
+
+UNDEFINED(A macro definition of THIS() is suppressed in order to access an actual function)
+UNDEFINED(A program defines an external identifier named LITERAL(setjmp))
+
 POSIX(1)
 */