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// Write/Read data to/from an ArrayBuffer
class ArrayBufferDataStream {
constructor(arrayBuffer) {
this.dataView = new DataView(arrayBuffer);
this.pos = 0;
}
readUint8() {
let rv = this.dataView.getUint8(this.pos);
this.pos += 1;
return rv;
}
writeUint8(value) {
this.dataView.setUint8(this.pos, value);
this.pos += 1;
}
readUint16() {
let rv = this.dataView.getUint16(this.pos);
this.pos += 2;
return rv;
}
writeUint16(value) {
this.dataView.setUint16(this.pos, value);
this.pos += 2;
}
readUint32() {
let rv = this.dataView.getUint32(this.pos);
this.pos += 4;
return rv;
}
writeUint32(value) {
this.dataView.setUint32(this.pos, value);
this.pos += 4;
}
readUint64() {
let rv = this.dataView.getBigUint64(this.pos);
this.pos += 8;
return Number(rv);
}
writeUint64(value) {
this.dataView.setBigUint64(this.pos, BigInt(value));
this.pos += 8;
}
readInt8() {
let rv = this.dataView.getInt8(this.pos);
this.pos += 1;
return rv;
}
writeInt8(value) {
this.dataView.setInt8(this.pos, value);
this.pos += 1;
}
readInt16() {
let rv = this.dataView.getInt16(this.pos);
this.pos += 2;
return rv;
}
writeInt16(value) {
this.dataView.setInt16(this.pos, value);
this.pos += 2;
}
readInt32() {
let rv = this.dataView.getInt32(this.pos);
this.pos += 4;
return rv;
}
writeInt32(value) {
this.dataView.setInt32(this.pos, value);
this.pos += 4;
}
readInt64() {
let rv = this.dataView.getBigInt64(this.pos);
this.pos += 8;
return Number(rv);
}
writeInt64(value) {
this.dataView.setBigInt64(this.pos, BigInt(value));
this.pos += 8;
}
readFloat32() {
let rv = this.dataView.getFloat32(this.pos);
this.pos += 4;
return rv;
}
writeFloat32(value) {
this.dataView.setFloat32(this.pos, value);
this.pos += 4;
}
readFloat64() {
let rv = this.dataView.getFloat64(this.pos);
this.pos += 8;
return rv;
}
writeFloat64(value) {
this.dataView.setFloat64(this.pos, value);
this.pos += 8;
}
writeString(value) {
const encoder = new TextEncoder();
// Note: in order to efficiently write this data, we first write the
// string data, reserving 4 bytes for the size.
const dest = new Uint8Array(this.dataView.buffer, this.pos + 4);
const encodeResult = encoder.encodeInto(value, dest);
if (encodeResult.read != value.length) {
throw new UniFFIError(
"writeString: out of space when writing to ArrayBuffer. Did the computeSize() method returned the wrong result?"
);
}
const size = encodeResult.written;
// Next, go back and write the size before the string data
this.dataView.setUint32(this.pos, size);
// Finally, advance our position past both the size and string data
this.pos += size + 4;
}
readString() {
const decoder = new TextDecoder();
const size = this.readUint32();
const source = new Uint8Array(this.dataView.buffer, this.pos, size)
const value = decoder.decode(source);
this.pos += size;
return value;
}
readBytes() {
const size = this.readInt32();
const bytes = new Uint8Array(this.dataView.buffer, this.pos, size);
this.pos += size;
return bytes
}
writeBytes(uint8Array) {
this.writeUint32(uint8Array.length);
value.forEach((elt) => {
dataStream.writeUint8(elt);
})
}
{%- for object in ci.object_definitions() %}
// Reads a {{ object.js_name() }} pointer from the data stream
// UniFFI Pointers are **always** 8 bytes long. That is enforced
// by the C++ and Rust Scaffolding code.
readPointer{{ object.js_name() }}() {
const pointerId = {{ object_ids.get(ci, object) }}; // {{ object_ids.name(ci, object) }}
const res = UniFFIScaffolding.readPointer(pointerId, this.dataView.buffer, this.pos);
this.pos += 8;
return res;
}
// Writes a {{ object.js_name() }} pointer into the data stream
// UniFFI Pointers are **always** 8 bytes long. That is enforced
// by the C++ and Rust Scaffolding code.
writePointer{{ object.js_name() }}(value) {
const pointerId = {{ object_ids.get(ci, object) }}; // {{ object_ids.name(ci, object) }}
UniFFIScaffolding.writePointer(pointerId, value, this.dataView.buffer, this.pos);
this.pos += 8;
}
{% endfor %}
}
function handleRustResult(result, liftCallback, liftErrCallback) {
switch (result.code) {
case "success":
return liftCallback(result.data);
case "error":
throw liftErrCallback(result.data);
case "internal-error":
if (result.data) {
throw new UniFFIInternalError(FfiConverterString.lift(result.data));
} else {
throw new UniFFIInternalError("Unknown error");
}
default:
throw new UniFFIError(`Unexpected status code: ${result.code}`);
}
}
class UniFFIError {
constructor(message) {
this.message = message;
}
toString() {
return `UniFFIError: ${this.message}`
}
}
class UniFFIInternalError extends UniFFIError {}
// Base class for FFI converters
class FfiConverter {
// throw `UniFFITypeError` if a value to be converted has an invalid type
static checkType(value) {
if (value === undefined ) {
throw new UniFFITypeError(`undefined`);
}
if (value === null ) {
throw new UniFFITypeError(`null`);
}
}
}
// Base class for FFI converters that lift/lower by reading/writing to an ArrayBuffer
class FfiConverterArrayBuffer extends FfiConverter {
static lift(buf) {
return this.read(new ArrayBufferDataStream(buf));
}
static lower(value) {
const buf = new ArrayBuffer(this.computeSize(value));
const dataStream = new ArrayBufferDataStream(buf);
this.write(dataStream, value);
return buf;
}
}
// Symbols that are used to ensure that Object constructors
// can only be used with a proper UniFFI pointer
const uniffiObjectPtr = Symbol("uniffiObjectPtr");
const constructUniffiObject = Symbol("constructUniffiObject");
UnitTestObjs.uniffiObjectPtr = uniffiObjectPtr;