Portability guide for 0.28.0?

[0-wiz-0]

0.28.0 broke a couple of exiv2 users. Please advise how the code should be updated.

kfilemetadata5 (https://github.com/KDE/kfilemetadata/blob/master/src/extractors/exiv2extractor.cpp)

[ 40%] Building CXX object src/extractors/CMakeFiles/kfilemetadata_taglibextractor.dir/__/kfilemetadata_debug.cpp.o
/scratch/sysutils/kfilemetadata5/work/kfilemetadata-5.98.0/src/extractors/exiv2extractor.cpp: In function 'QVariant {anonymous}::toVariantLong(const Exiv2::Value&)':
/scratch/sysutils/kfilemetadata5/work/kfilemetadata-5.98.0/src/extractors/exiv2extractor.cpp:78:31: error: 'const class Exiv2::Value' has no member named 'toLong'
   78 |         qlonglong val = value.toLong();
      |                               ^~~~~~
/scratch/sysutils/kfilemetadata5/work/kfilemetadata-5.98.0/src/extractors/exiv2extractor.cpp: In member function 'double KFileMetaData::Exiv2Extractor::fetchGpsAltitude(const Exiv2::ExifData&)':
/scratch/sysutils/kfilemetadata5/work/kfilemetadata-5.98.0/src/extractors/exiv2extractor.cpp:313:39: error: 'const class Exiv2::Value' has no member named 'toLong'
  313 |             auto altRef = it->value().toLong();
      |                                       ^~~~~~

geeqie (https://github.com/BestImageViewer/geeqie/blob/master/src/exiv2.cc)
geeqie.log

gexiv2 (https://gitlab.gnome.org/GNOME/gexiv2/-/issues/74)
gexiv2.log

Thanks!

[0-wiz-0]

Here's the kfilemetadata5 issue for this:
https://bugs.kde.org/show_bug.cgi?id=469607

[0-wiz-0]

geeqie one: BestImageViewer/geeqie#1090

[neheb]

Use toInt64 instead

[0-wiz-0]

Thanks. Do you have suggestions for geeqie too?
(gexiv2 might be fixed in their git head.)

[neheb]

Partial: https://github.com/gerbera/gerbera/blob/master/src/metadata/exiv2_handler.cc#L45

[kevinbackhouse]

In 0.28.0, we have attempted to eliminate the long type because it is 32-bit on Windows and 64-bit on most other platforms. That's why toLong has been replaced by toInt64.

[kmilos]

Btw, this seems to be always true for me (MSYS2 UCRT64 GCC 12.2) now somehow for any type

exiv2/include/exiv2/xmp_exiv2.hpp

Lines 398 to 402 in 0a9b57a

	#ifdef __cpp_if_constexpr
	if constexpr (std::is_same_v<T, bool>) {
	#else
	if (std::is_same<T, bool>::value) {
	#endif

so e.g. this darktable code now fails:
xmp[regionKey + "/mwg-rs:Area/stArea:w"] = XmpTextValue(std::to_string(w));
with

C:/msys64/opt/exiv2/include/exiv2/xmp_exiv2.hpp:403:36: error: could not convert 'value' from 'const
 Exiv2::XmpTextValue' to 'bool'
  403 |     setValue(Exiv2::toString(value ? "True" : "False"));
      |                              ~~~~~~^~~~~~~~~~~~~~~~~~
      |                                    |
      |                                    const Exiv2::XmpTextValue
compilation terminated due to -Wfatal-errors.

[kmilos]

Also had to change Exiv2::AnyError to Exiv2::Error, and DataBuf access.

[neheb]

Thanks. Do you have suggestions for geeqie too?
(gexiv2 might be fixed in their git head.)

I have a patch for this.

[neheb]

Btw, this seems to be always true for me (MSYS2 UCRT64 GCC 12.2) now somehow for any type

exiv2/include/exiv2/xmp_exiv2.hpp

Lines 398 to 402 in 0a9b57a

	#ifdef __cpp_if_constexpr
	if constexpr (std::is_same_v<T, bool>) {
	#else
	if (std::is_same<T, bool>::value) {
	#endif

so e.g. this darktable code now fails: xmp[regionKey + "/mwg-rs:Area/stArea:w"] = XmpTextValue(std::to_string(w)); with

C:/msys64/opt/exiv2/include/exiv2/xmp_exiv2.hpp:403:36: error: could not convert 'value' from 'const
 Exiv2::XmpTextValue' to 'bool'
  403 |     setValue(Exiv2::toString(value ? "True" : "False"));
      |                              ~~~~~~^~~~~~~~~~~~~~~~~~
      |                                    |
      |                                    const Exiv2::XmpTextValue
compilation terminated due to -Wfatal-errors.

After speaking with ChatGPT, it seems if constexpr should be removed from headers.

[0-wiz-0]

Thanks. Do you have suggestions for geeqie too?
(gexiv2 might be fixed in their git head.)

I have a patch for this.

That's great! Is it for exiv2 or geeqie? If the latter, can you please share it with at BestImageViewer/geeqie#1090 ?

[kmilos]

Well, looks like Arch maintainers did it: https://archlinux.org/todo/exiv2-028/ 🚀

[neheb]

Great

[neheb]

geeqie is fixed. can this issue be closed?

[0-wiz-0]

Thanks for the help!