Fix memory growth problem.

3 files changed, 36 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index 4f21f0ff..3049827a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2014-11-11         Arnold D. Robbins     <arnold@skeeve.com>
+
+	Don't let memory used increase linearly in the size of
+	the input.  Problem reported by dragan legic
+	<dragan.legic@yandex.ru>.
+
+	* field.c (set_record): NUL-terminate the buffer.
+	* interpret.h (r_interpret): Op_field_spec: if it's $0, increment
+	the valref.  Op_store_var: if we got $0, handle it appropriately.
+
 2014-11-10         Arnold D. Robbins     <arnold@skeeve.com>
 
 	Reorder main.c activities so that we can set a locale on the
diff --git a/field.c b/field.c
index 4819ea94..7b4f2190 100644
--- a/field.c
+++ b/field.c
@@ -277,6 +277,12 @@ set_record(const char *buf, int cnt)
 	/* copy the data */
 	memcpy(databuf, buf, cnt);
 
+	/*
+	 * Add terminating '\0' so that C library routines 
+	 * will know when to stop.
+	 */
+	databuf[cnt] = '\0';
+
 	/* manage field 0: */
 	unref(fields_arr[0]);
 	getnode(n);
diff --git a/interpret.h b/interpret.h
index 28804330..593f11a6 100644
--- a/interpret.h
+++ b/interpret.h
@@ -340,7 +340,12 @@ uninitialized_scalar:
 			lhs = r_get_field(t1, (Func_ptr *) 0, true);
 			decr_sp();
 			DEREF(t1);
-			r = dupnode(*lhs);     /* can't use UPREF here */
+			/* only for $0, up ref count */
+			if (*lhs == fields_arr[0]) {
+				r = *lhs;
+				UPREF(r);
+			} else
+				r = dupnode(*lhs);
 			PUSH(r);
 			break;
 
@@ -649,11 +654,22 @@ mod:
 			lhs = get_lhs(pc->memory, false);
 			unref(*lhs);
 			r = pc->initval;	/* constant initializer */
-			if (r == NULL)
-				*lhs = POP_SCALAR();
-			else {
+			if (r != NULL) {
 				UPREF(r);
 				*lhs = r;
+			} else {
+				r = POP_SCALAR();
+
+				/* if was a field, turn it into a var */
+				if ((r->flags & FIELD) == 0) {
+					*lhs = r;
+				} else if (r->valref == 1) {
+					r->flags &= ~FIELD;
+					*lhs = r;
+				} else {
+					*lhs = dupnode(r);
+					DEREF(r);
+				}
 			}
 			break;