Add missing C file

webassembly/webp.c

@@ -0,0 +1,44 @@
+#include "emscripten.h"
+#include "src/webp/encode.h"
+#include <stdlib.h>
+
+EMSCRIPTEN_KEEPALIVE
+int version() {
+  return WebPGetEncoderVersion();
+}
+
+EMSCRIPTEN_KEEPALIVE
+uint8_t* create_buffer(int width, int height) {
+  return malloc(width * height * 4 * sizeof(uint8_t));
+}
+
+EMSCRIPTEN_KEEPALIVE
+void destroy_buffer(uint8_t* p) {
+  free(p);
+}
+
+int result[2];
+EMSCRIPTEN_KEEPALIVE
+void encode(uint8_t* img_in, int width, int height, float quality) {
+  uint8_t* img_out;
+  size_t size;
+  size = WebPEncodeRGBA(img_in, width, height, width * 4, quality, &img_out);
+  result[0] = (int)img_out;
+  result[1] = size;
+}
+
+EMSCRIPTEN_KEEPALIVE
+void free_result(uint8_t* result) {
+  WebPFree(result);
+}
+
+EMSCRIPTEN_KEEPALIVE
+int get_result_pointer() {
+  return result[0];
+}
+
+EMSCRIPTEN_KEEPALIVE
+int get_result_size() {
+  return result[1];
+}
+