1514393 - Export nsJPEGEncoder and isolate its internals

Status: RESOLVED FIXED

(Core :: Graphics, enhancement)

Description

[Barret Rennie [:barret] (they/them)]

nsJPEGEncoder is currently in an unexported header, which means to acquire a JPEG encoder we need to use XPCOM `do_CreateInstance`. Additionally, exposing this header for use in, e.g., the compositor to capture screenshots results in duplicate type definitions on Windows (from libjpeg and windows.h). This can be mitigated by not presenting the callbacks that libjpeg uses in the public header.

Comment 1

[Barret Rennie [:barret] (they/them)]

Attachment: Bug 1514393 - Isolate internals of nsJPEGEncoder r?aosmond

Both libjpeg and windows.h typedef `boolean` to different types (`int` and
`unsiched char` respectively) and nsJPEGEncoder's public definition includes a
function that returns a `boolean`. Exposing this header results in type
conflicts.

We now isolate the internals of nsJPEGEncoder into a friend class whose
internals are hidden from the publica, allowing the header to exported.

Comment 2

[Barret Rennie [:barret] (they/them)]

Attachment: Bug 1514393 - Export nsJPEGEncoder header r?aosmond

Comment 3

[Barret Rennie [:barret] (they/them)]

Try run: https://treeherder.mozilla.org/#/jobs?repo=try&revision=a147bb7b5de9123fcf3e46d93c9f031aa0381c0d&selectedJob=217124300

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/d81fe57537cb
Isolate internals of nsJPEGEncoder r=aosmond
https://hg.mozilla.org/integration/autoland/rev/9d5088dfe7d3
Export nsJPEGEncoder header r=aosmond

Comment 5

[Barret Rennie [:barret] (they/them)]

Attachment: Bug 1514393 - Correct formatting in nsJPEGEncoder.cpp r?aosmond

Comment 6

[Arthur Iakab [arthur_iakab]]

https://hg.mozilla.org/mozilla-central/rev/d81fe57537cb
https://hg.mozilla.org/mozilla-central/rev/9d5088dfe7d3

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b350b5b4781e
Correct formatting in nsJPEGEncoder.cpp r=aosmond

Comment 8

[Arthur Iakab [arthur_iakab]]

https://hg.mozilla.org/mozilla-central/rev/d81fe57537cb
https://hg.mozilla.org/mozilla-central/rev/9d5088dfe7d3

Comment 9

[Arthur Iakab [arthur_iakab]]

https://hg.mozilla.org/mozilla-central/rev/b350b5b4781e