From 8c44869f1dc2cdc7337d5a2a4f64e10494b0fb2f Mon Sep 17 00:00:00 2001 From: isaacs Date: Tue, 5 Mar 2013 22:09:27 -0800 Subject: [PATCH] stream: Increase highWaterMark on large reads If the consumer of a Readable is asking for N bytes, and N > hwm, then clearly we have set the hwm to low, and ought to increase it. Fix #4931 --- lib/_stream_readable.js | 5 ++ .../test-stream-readable-flow-recursion.js | 69 +++++++++++++++++++ 2 files changed, 74 insertions(+) create mode 100644 test/simple/test-stream-readable-flow-recursion.js diff --git a/lib/_stream_readable.js b/lib/_stream_readable.js index 17d186f9f3d..1131b24a2e1 100644 --- a/lib/_stream_readable.js +++ b/lib/_stream_readable.js @@ -181,6 +181,11 @@ function howMuchToRead(n, state) { if (n <= 0) return 0; + // If we're asking for more than the target buffer level, + // then raise the water mark. + if (n > state.highWaterMark) + state.highWaterMark = n; + // don't have that much. return null, unless we've ended. if (n > state.length) { if (!state.ended) { diff --git a/test/simple/test-stream-readable-flow-recursion.js b/test/simple/test-stream-readable-flow-recursion.js new file mode 100644 index 00000000000..3bad0d9f7ba --- /dev/null +++ b/test/simple/test-stream-readable-flow-recursion.js @@ -0,0 +1,69 @@ +// Copyright Joyent, Inc. and other Node contributors. +// +// Permission is hereby granted, free of charge, to any person obtaining a +// copy of this software and associated documentation files (the +// "Software"), to deal in the Software without restriction, including +// without limitation the rights to use, copy, modify, merge, publish, +// distribute, sublicense, and/or sell copies of the Software, and to permit +// persons to whom the Software is furnished to do so, subject to the +// following conditions: +// +// The above copyright notice and this permission notice shall be included +// in all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS +// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN +// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, +// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR +// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE +// USE OR OTHER DEALINGS IN THE SOFTWARE. + +var common = require('../common'); +var assert = require('assert'); + +// this test verifies that passing a huge number to read(size) +// will push up the highWaterMark, and cause the stream to read +// more data continuously, but without triggering a nextTick +// warning or RangeError. + +var Readable = require('stream').Readable; + +// throw an error if we trigger a nextTick warning. +process.throwDeprecation = true; + +var stream = new Readable({ highWaterMark: 2, bufferSize: 2 }); +var reads = 0; +stream._read = function(size) { + reads++; + stream.push(new Buffer(size)); +}; + +var depth = 0; + +function flow(stream, size, callback) { + depth += 1; + var chunk = stream.read(size); + + if (!chunk) + stream.once('readable', flow.bind(null, stream, size, callback)); + else + callback(chunk); + + depth -= 1; + console.log('flow(' + depth + '): exit'); +} + +flow(stream, 5000, function() { + console.log('complete (' + depth + ')'); +}); + +process.on('exit', function(code) { + assert.equal(reads, 5000); + // we pushed up the high water mark + assert.equal(stream._readableState.highWaterMark, 5000); + assert.equal(stream._readableState.length, 5000); + assert(!code); + assert.equal(depth, 0); + console.log('ok'); +});