1 files changed, 27 insertions, 0 deletions
diff --git a/image/png/iend.ha b/image/png/iend.ha
new file mode 100644
index 0000000..97651a3
--- /dev/null
+++ b/image/png/iend.ha
@@ -0,0 +1,27 @@
+use bufio;
+use io;
+use memio;
+
+// Reads an IEND chunk from a [[reader]]. This function simply performs a sanity
+// check and verifies the chunk checksum.
+export fn iend_read(src: *reader) (void | error) = {
+	assert(chunk_type(src) == IEND,
+		"Attempted to call iend_read on non-IEND chunk");
+	io::copy(io::empty, src)?;
+};
+
+@test fn iend_reader() void = {
+	const src = memio::fixed(simple_png);
+	const read = newreader(&src) as reader;
+	assert(nextchunk(&read) as u32 == IHDR);
+	io::copy(io::empty, &read)!;
+
+	for (true) {
+		if (nextchunk(&read) as u32 == IEND) {
+			break;
+		};
+		io::copy(io::empty, &read)!;
+	};
+
+	iend_read(&read)!;
+};