hare

commit b6df30cf544f96796e536f65e70db9dfc73e7d5b
parent b2f9cad339eb3c6d48df27267304a24aad39253d
Author: Eyal Sawady <ecs@d2evs.net>
Date:   Thu,  4 Feb 2021 14:28:43 -0500

rt: add rt::ensure

Diffstat:
A
rt/ensure.ha
 | 
15
+++++++++++++++

1 file changed, 15 insertions(+), 0 deletions(-)
diff --git a/rt/ensure.ha b/rt/ensure.ha
@@ -0,0 +1,15 @@
+export type slice = struct {
+	data: *void,
+	length: size,
+	capacity: size,
+};
+
+export fn ensure(s: *slice, membsz: size, length: size) void = {
+	// TODO: make sure length * membsz < SIZE_MAX
+	for (s.capacity < length) {
+		s.capacity *= 2z;
+	};
+	let data = realloc(s.data, s.capacity * membsz);
+	assert(data != null: nullable *void);
+	s.data = data;
+};