2068156 - Skip parsing a URI to look for a password the spec cannot hold

Status: RESOLVED FIXED

(DevTools :: Console, enhancement)

Comment 1

[Mayank Bansal]

Attachment: Bug 2067000 - Skip parsing a URI to look for a password the spec cannot hold. r?#necko-reviewers,#dom-core-reviewers

Console and nsScriptError both build an nsIURI out of a script filename on
every message, purely to ask whether it carries a password worth hiding. On
the console.clear() testcase in the bug that parse is 19% of the content
process main thread.

A password only reaches nsIURI through a userinfo component, and every
implementation that can report a non-empty one - nsStandardURL, DefaultURI,
and SubstitutingJARURI, which forwards to its source URL - derives it from a
literal '@'. Scanning for that byte first leaves the sanitizing path
unchanged and skips the parse otherwise.

Both call sites now share NS_GetSanitizedSpecFromSpec rather than spelling
the same check two different ways. That unifies one behaviour difference: on
a spec that has a password which cannot be hidden, Console used to fall back
to the raw spec, and nsScriptError to an empty string. The helper keeps
nsScriptError's behaviour, since emitting a spec known to contain a password
is the one outcome worth avoiding.

Console also had an NS_IsMainThread() check in front of the sanitizing,
added by bug 1246091 in 2016 when this code first became reachable from
workers and NS_NewURI was main thread only. Bug 1536744 renamed
NS_NewURIOnAnyThread to NS_NewURI in 2019, and nsIURI is immutable and
threadsafe, so the check has been dead weight since then. Dropping it also
means worker console events reaching a chrome console event handler - via
setConsoleEventHandler or retrieveConsoleEvents - get the same sanitizing
main thread ones already got.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/de09a5f0cc77
https://hg.mozilla.org/integration/autoland/rev/77f7147935b0
Bug 2067000 - Skip parsing a URI to look for a password the spec cannot hold. r=necko-reviewers,valentin

Comment 3

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/77f7147935b0