@recaptime-dev's working patches + fork for Phorge, a community fork of Phabricator. (Upstream dev and stable branches are at upstream/main and upstream/stable respectively.)
hq.recaptime.dev/wiki/Phorge
phorge
phabricator
Add a couple of clarifying comments to the Mercurial protocol parser
Summary: See D18857. Ref T13036. See PHI275. Explain what's going on here a little better since it isn't entirely obvious and debugging these stream parsers is a gigantic pain.
Test Plan: Read text.
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13036
Differential Revision: https://secure.phabricator.com/D18859
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+19
src/applications/diffusion/ssh/DiffusionMercurialWireClientSSHProtocolChannel.php
+19
src/applications/diffusion/ssh/DiffusionMercurialWireClientSSHProtocolChannel.php
···
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$this->state = 'arguments';
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}
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} else if ($this->state == 'data-length') {
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// We're reading the length of a chunk of raw data. It looks like
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// this:
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//
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// <length-in-bytes>\n
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//
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// The length is human-readable text (for example, "4096"), and
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// may be 0.
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$line = $this->readProtocolLine();
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if ($line === null) {
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break;
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$this->state = 'data-bytes';
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}
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} else if ($this->state == 'data-bytes') {
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// We're reading some known, nonzero number of raw bytes of data.
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// If we don't have any more bytes on the buffer yet, just bail:
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// otherwise, we'll emit a pointless and possibly harmful 0-byte data
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// frame. See T13036 for discussion.
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$bytes = substr($this->buffer, 0, $this->expectBytes);
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$this->buffer = substr($this->buffer, strlen($bytes));
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$this->expectBytes -= strlen($bytes);
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// NOTE: We emit a data frame as soon as we read some data. This can
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// cause us to repackage frames: for example, if we receive one large
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// frame slowly, we may emit it as several smaller frames. In theory
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// this is good; in practice, Mercurial never seems to select a frame
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// size larger than 4096 bytes naturally and this may be more
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// complexity and trouble than it is worth. See T13036.
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$messages[] = $this->newDataMessage($bytes);
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