qr2

deno_wasm_qr/decodeqr/src/lib.rs

@@ -2,24 +2,33 @@ use std::ffi::CString;
 use std::os::raw::c_char;
 
 pub const SAMPLE_QR_BYTES: &[u8]   = std::include_bytes!("sample_qr.png");
+pub const SAMPLE_QR_BYTES_2: &[u8] = std::include_bytes!("sample_qr_2.png");
 
 #[no_mangle]
 pub extern "C" fn parse_default_qr() -> *mut c_char {
-    let s = CString::new(parse_qr()).unwrap();
+    let s = CString::new(parse_qr(SAMPLE_QR_BYTES)).unwrap();
     s.into_raw()
 }
 
-pub fn parse_qr() -> String {
-    let img = image::load_from_memory(SAMPLE_QR_BYTES).unwrap();
+#[no_mangle]
+pub extern "C" fn parse_default_qr_2() -> *mut c_char {
+    let s = CString::new(parse_qr(SAMPLE_QR_BYTES_2)).unwrap();
+    s.into_raw()
+}
+
+pub fn parse_qr(bs: &[u8]) -> String {
+    let img = match image::load_from_memory(bs) {
+        Ok(i) => i, Err(e) => return format!("Load image error: {}", e),
+    };
 
     let decoder = bardecoder::default_decoder();
 
     let mut ret = vec![];
     let results = decoder.decode(&img);
     for result in results {
-        let qr = result.unwrap();
+        let qr = result.unwrap_or_else(|e| format!("Decode QR error: {}", e));
         println!("{}", qr);
         ret.push(qr);
     }
-    ret.join(",")
+    ret.join("||")
 }

deno_wasm_qr/parse_qr.ts

@@ -4,6 +4,7 @@ const wasmInstance = new WebAssembly.Instance(wasmModule);
 
 const linearMemory = wasmInstance.exports.memory;
 
+// from https://tilman.xyz/blog/2019/12/building-webassembly-for-deno/
 function readString(memory, ptr) {
     const mem = new Uint8Array(memory.buffer, ptr);
     let length;
@@ -11,4 +12,5 @@ function readString(memory, ptr) {
     return new TextDecoder("utf-8").decode(new Uint8Array(mem.buffer, ptr, length));
 }
 
-console.log(readString(linearMemory, wasmInstance.exports.parse_default_qr()));
+console.log("DECODED:\n" + readString(linearMemory, wasmInstance.exports.parse_default_qr()));
+console.log("DECODED:\n" + readString(linearMemory, wasmInstance.exports.parse_default_qr_2()));