1486386 - cairo-type1-subset.c uses isxdigit()

Status: RESOLVED FIXED

(Core :: Graphics, defect, P3)

Description

[Henri Sivonen (:hsivonen)]

cairo-type1-subset.c uses isxdigit(). This has 2 bugs:

1) On platforms where char is signed, calling isxdigit() with a char argument is UB when the most-significant bit of the char is set.

2) According to MSDN, isxdigit() is locale-sensitive. According to glibc sources, isxdigit() does a lookup from locale-dependent tables, but I didn't check if the that part of the tables actually varies by locale.

Instead of using isxdigit(), Cairo should have a function that does
('0' <= c && c <= '9') || ('A' <= c && c <= 'f') || ('A' <= c && c <= 'F')

Comment 1

[Henri Sivonen (:hsivonen)]

Upstream issue:
https://gitlab.freedesktop.org/cairo/cairo/issues/335

Comment 2

[Henri Sivonen (:hsivonen)]

(In reply to Henri Sivonen (:hsivonen) from comment #0)
> Instead of using isxdigit(), Cairo should have a function that does
> ('0' <= c && c <= '9') || ('A' <= c && c <= 'f') || ('A' <= c && c <= 'F')

'a' instead of 'A' the first time.

Comment 3

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1486386 - Cherry-pick cairo commit 30a0ae56d8eaf7735d6f4a8a889e9c54bc0debc1 to fix isxdigit issue. r=jrmuizel

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/ae62445f52a2
Cherry-pick cairo commit 30a0ae56d8eaf7735d6f4a8a889e9c54bc0debc1 to fix isxdigit issue. r=jrmuizel

Comment 5

[Noemi Erli[:noemi_erli]]

https://hg.mozilla.org/mozilla-central/rev/ae62445f52a2