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compress.js
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compress.js
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var brotli = require('./build/encode');
/**
* Compresses the given buffer
* The second parameter is optional and specifies whether the buffer is
* text or binary data (the default is binary).
* Returns null on error
*/
module.exports = function(buffer, opts) {
// default to binary data
var quality = 11;
var mode = 0;
var lgwin = 22;
var dictionary = "";
if (typeof opts === 'boolean') {
mode = opts ? 0 : 1;
} else if (typeof opts === 'object') {
quality = opts.quality || 11;
mode = opts.mode || 0;
lgwin = opts.lgwin || 22;
dictionary = opts.dictionary || "";
}
// allocate input buffer and copy data to it
var buf = brotli._malloc(buffer.length);
brotli.HEAPU8.set(buffer, buf);
// allocate dictionary buffer and copy data to it
var dict = brotli._malloc(dictionary.length);
brotli.HEAPU8.set(dictionary, dict);
// allocate output buffer (same size + some padding to be sure it fits), and encode
var outBuf = brotli._malloc(buffer.length + 1024);
var encodedSize = brotli._encodeWithDictionary(quality, lgwin, mode, buffer.length, buf, dictionary.length, dict, buffer.length + 1024, outBuf);
var outBuffer = null;
if (encodedSize !== -1) {
// allocate and copy data to an output buffer
outBuffer = new Uint8Array(encodedSize);
outBuffer.set(brotli.HEAPU8.subarray(outBuf, outBuf + encodedSize));
}
// free malloc'd buffers
brotli._free(buf);
brotli._free(outBuf);
return outBuffer;
};