Make built-in font data read-only

[Alexandre Julliard]

Ian Pilcher <ian.pilcher at home.com> writes:

> If all pointers have to be eliminated, I can't see any way to do it.
> In order for the code to have any kind of sanity, built-in font metrics
> and dynamically loaded font metrics have to use the same data model, and
> I don't think it's even remotely practical to get rid of the pointers in
> the case of the dynamically loaded metrics.

Well, if it's not feasible so be it. But if it's at all possible I
think it's worth some reasonable amount of trouble.

> I'm open to suggestions, but I think that the effort involved in doing
> this (assuming a sane way could be found) probably far outweighs the
> benefit (less swap usage if the data is paged out; is there any other
> benefit?).

The main benefit is sharing between processes; so if you have 10
processes that want to print you only have one copy of the font data
in memory. Plus it gets loaded on-demand so data that isn't used
doesn't need to be loaded from disk at all.

> Just in case I get inspired, though, what tool/command are you using to
> determine read-only vs. read/write data sizes?  Can I just go by what
> objdump says about .data and .rodata?

objdump is fine yes. size works too, though I seem to remember some
versions not counting .rodata correctly.

-- 
Alexandre Julliard
julliard at winehq.com