Icard/angular-clarity-master(work.../node_modules/pngjs/lib/sync-reader.js

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2024-07-16 14:55:36 +00:00
"use strict";
let SyncReader = (module.exports = function (buffer) {
this._buffer = buffer;
this._reads = [];
});
SyncReader.prototype.read = function (length, callback) {
this._reads.push({
length: Math.abs(length), // if length < 0 then at most this length
allowLess: length < 0,
func: callback,
});
};
SyncReader.prototype.process = function () {
// as long as there is any data and read requests
while (this._reads.length > 0 && this._buffer.length) {
let read = this._reads[0];
if (
this._buffer.length &&
(this._buffer.length >= read.length || read.allowLess)
) {
// ok there is any data so that we can satisfy this request
this._reads.shift(); // == read
let buf = this._buffer;
this._buffer = buf.slice(read.length);
read.func.call(this, buf.slice(0, read.length));
} else {
break;
}
}
if (this._reads.length > 0) {
return new Error("There are some read requests waitng on finished stream");
}
if (this._buffer.length > 0) {
return new Error("unrecognised content at end of stream");
}
};