little size compeitino

1 files changed, 15 insertions, 0 deletions

diff --git a/examples/wasm-tiny-png/src/lib.rs b/examples/wasm-tiny-png/src/lib.rs
new file mode 100644
index 0000000..ff553f1
--- /dev/null
+++ b/examples/wasm-tiny-png/src/lib.rs
@@ -0,0 +1,15 @@
+#[no_mangle]
+pub unsafe fn decode_png(input: *const u8, input_len: usize, output: *mut u8, output_len: usize) -> usize {
+	let mut input = core::slice::from_raw_parts(input, input_len);
+	let output = core::slice::from_raw_parts_mut(output, output_len);
+	let Ok(header) = tiny_png::read_png_header(&mut input) else {
+		return 0;
+	};
+	let required_bytes = header.required_bytes();
+	if output_len >= required_bytes {
+		if tiny_png::read_png(&mut input, Some(&header), output).is_err() {
+			return 0;
+		}
+	}
+	required_bytes
+}