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// This is https://github.com/pyodide/pyodide/blob/main/src/core/sentinel.ts.
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// It goes into `pyodide.js` not `pyodide.asm.js`. We don't use `pyodide.js` so we have to reproduce
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// it here.
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import { wasmInstantiate } from 'pyodide-internal:pool/builtin_wrappers';
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// Per https://github.com/tc39/proposal-arraybuffer-base64/issues/51#issuecomment-3010378969, we
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// should be able to replace `decodeBase64()` with `Uint8Array.fromBase64()` once we update to a v8
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// released after September 2nd.
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const base64Lookup = new Uint8Array(128);
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for (let t = 0; t < 64; t++) {
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  let idx;
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  if (t < 26) {
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    idx = t + 65;
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  } else if (t < 52) {
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    idx = t + 71;
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  } else if (t < 62) {
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    idx = t - 4;
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  } else {
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    idx = t * 4 - 205;
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  }
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  base64Lookup[idx] = t;
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}
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function decodeBase64(input: string): Uint8Array {
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  const outputSize = ((input.length * 3) / 4) | 0;
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  const output = new Uint8Array(outputSize);
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  let inIdx = 0;
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  let outIdx = 0;
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  while (inIdx < input.length) {
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    const chunk1 = base64Lookup[input.charCodeAt(inIdx++)]!;
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    const chunk2 = base64Lookup[input.charCodeAt(inIdx++)]!;
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    const chunk3 = base64Lookup[input.charCodeAt(inIdx++)]!;
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    const chunk4 = base64Lookup[input.charCodeAt(inIdx++)]!;
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    output[outIdx++] = (chunk1 << 2) | (chunk2 >> 4);
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    output[outIdx++] = (chunk2 << 4) | (chunk3 >> 2);
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    output[outIdx++] = (chunk3 << 6) | chunk4;
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  }
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  return output;
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}
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// This string is https://github.com/pyodide/pyodide/blob/main/src/core/sentinel.wat assembled and
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// hex encoded.
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const sentinelWasm = decodeBase64(
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  'AGFzbQEAAAABDANfAGAAAW9gAW8BfwMDAgECByECD2NyZWF0ZV9zZW50aW5lbAAAC2lzX3NlbnRpbmVsAAEKEwIHAPsBAPsbCwkAIAD7GvsUAAs'
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);
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export async function getSentinelImport() {
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  const imports = {};
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  const { instance } = await wasmInstantiate(sentinelWasm, imports);
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  return instance.exports;
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}