[Fontconfig] Query for default config without force initialization if absent

[Francesco Pretto]

On Sat, 12 Feb 2022 at 20:22, Behdad Esfahbod <behdad at behdad.org> wrote:
> You might find this blogpost of mine useful:
>   http://mces.blogspot.com/2015/05/how-to-use-custom-application-fonts.html
>

Hi Behdad,

yes, I am really finding your article very useful and I am archiving
it immediately for future reference! Actually I was very close in the
sense I was already able to create a custom fontconfig configuration
and add lookup folders, but I didn't understood the usefulness of
using FcInitLoadConfig() and FcInitLoadConfigAndFonts() for creating a
local configuration based on existing configuration files/fallback
config. I guess I was confused by the "default" configuration that can
be retrieved with FcConfigGetCurrent, which is really a shared
singleton.

On Sat, 12 Feb 2022 at 20:20, Lawrence D'Oliveiro
<ldo at geek-central.gen.nz> wrote:
> Better idea: use the default config, unless the caller specifies
> alternate settings for you instead.

It's something I was already doing, but somehow I don't know if
trusting fontconfig system settings in some architectures, especially
the ones that don't use fontonfig as a common tool (eg.
Windows/iOS/android). Also, since I need to alter font search paths, I
will end create my custom configurations or
FcInitLoadConfigAndFonts/FcInitLoadConfig as suggested by Behdad where
I feel I can trust system settings/fallbacks, possibly checking first
the existence of a configuration file with FcConfigGetFilename(NULL,
NULL), and forget about the default configuration that can be
retrieved with FcConfigGetCurrent.

I think my case can be considered closed. Digressing more, I wonder if
there could have been a different model where the one always copy its
local configuration from a read-only singleton. There's no
"FcConfigCopy" so the design was clearly different.

Cheers,
Francesco