lukechilds/node - node - Gitea: Git with a cup of tea

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isaacs b0de1e4a41 stream: Fix unshift() race conditions Fix #5272 The consumption of a readable stream is a dance with 3 partners. 1. The specific stream Author (A) 2. The Stream Base class (B), and 3. The Consumer of the stream (C) When B calls the _read() method that A implements, it sets a 'reading' flag, so that parallel calls to _read() can be avoided. When A calls stream.push(), B knows that it's safe to start calling _read() again. If the consumer C is some kind of parser that wants in some cases to pass the source stream off to some other party, but not before "putting back" some bit of previously consumed data (as in the case of Node's websocket http upgrade implementation). So, stream.unshift() will generally never be called by A, but only called by C. Prior to this patch, stream.unshift() also unset the state.reading flag, meaning that C could indicate the end of a read, and B would dutifully fire off another _read() call to A. This is inappropriate. In the case of fs streams, and other variably-laggy streams that don't tolerate overlapped _read() calls, this causes big problems. Also, calling stream.shift() after the 'end' event did not raise any kind of error, but would cause very strange behavior indeed. Calling it after the EOF chunk was seen, but before the 'end' event was fired would also cause weird behavior, and could lead to data being lost, since it would not emit another 'readable' event. This change makes it so that: 1. stream.unshift() does not set state.reading = false 2. stream.unshift() is allowed up until the 'end' event. 3. unshifting onto a EOF-encountered and zero-length (but not yet end-emitted) stream will defer the 'end' event until the new data is consumed. 4. pushing onto a EOF-encountered stream is now an error. So, if you read(), you have that single tick to safely unshift() data back into the stream, even if the null chunk was pushed, and the length was 0.		12 years ago
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addons	test: modify async native test.js to test for #4820	12 years ago
disabled	Merge remote-tracking branch 'ry/v0.8' into master	12 years ago
fixtures	test: Fix debugger repl tests	12 years ago
gc	test: use the debug build of node-weak when necessary	13 years ago
internet	DNS: Support NAPTR queries	12 years ago
message	process: separate nextTick domain logic	12 years ago
pummel	test: Pass cli flags in pummel/test-regress-GH-892	12 years ago
simple	stream: Fix unshift() race conditions	12 years ago
common.js	test: optionally set common.PORT via env variable	12 years ago