ppdc decimal separator is locale-dependent (dot or comma)

[ValdikSS]

Describe the bug

ppdc PPD file compiler fails to parse the HWMargins (and possibly other) floating point data when . is used as a separator on a system where locale uses , as a separator, and vice versa.

HWMargins 12.5 12.5 12.5 12.5 in the .drv file would be handled as 0 0 0 0 when ppdc is run with LC_NUMERIC=ru_RU.UTF-8 (comma separator), resulting in incorrect ImageableArea in the final ppd file.

To Reproduce

Use this minimal .drv file:

Manufacturer "Test"
Version "1.0.0"

#include <font.defs>
Font *

HWMargins 12.5 12.5 12.5 12.5

#include <media.defs>
*MediaSize Letter
MediaSize Legal
MediaSize A4

*Resolution k 1 0 0 0 "600dpi/600 DPI"

ModelName "TEST-01"
PCFileName "test01.ppd"

1. Run with Russian locale: LC_NUMERIC=ru_RU.UTF-8 ./ppdc -v -I ../data/ -d ppd-test simple.drv
2. Check ImageableArea:

*ImageableArea Letter/US Letter: "0 0 612 792"

1. Run with US locale: LC_NUMERIC=en_US.UTF-8 ./ppdc -v -I ../data/ -d ppd-test simple.drv
2. Check ImageableArea:

*ImageableArea Letter/US Letter: "12.5 12.5 599.5 779.5"

Expected behavior

ppdc should not be locale-dependent, should give the same result on any locale.
I assume that all .drv files use dot as a separator, so it should be sufficient to force either US or C locale.

System Information:
Tested on CUPS 2.4.2, CUPS 2.4.13, current git master (7765ca9)

[ValdikSS]

As an alternative, LC_NUMERIC could be set in _cupsSetLocale().

[michaelrsweet]

We actually have a private API for this but weren't using it:

[master 3507bb9] Use locale-insensitive decoding of real numbers (Issue #1263)

[2.4.x 0f381a0] Use locale-insensitive decoding of real numbers (Issue #1263)