Guidelines to move to API v2
After updating to API v2, the old code stops compiling, and it takes some contemplation to fix the errors. It would be good to have some guidelines for common problems.
This, for example, doesn't compile anymore:
auto caps = Gst::Caps::new_empty_simple("video/x-raw");
caps.set_value("format", "Y444");I had to change it to
namespace GObj {
using namespace gi::repository::GObject;
}
auto caps = Gst::Caps::new_empty_simple("video/x-raw");
caps.set_value("format", GObj::Value("Y444"));Is it a bug or intended? Is there a less verbose v2 special syntax?
This stopped compiling, and I don't know what to do:
auto appsrc = Gst::AppSrc{};
// ...
appsrc.property_caps().set(caps);I tried
auto appsrc = Gst::AppSrc{};
// ...
appsrc.property_caps().set(caps.copy_());It didn't help.
Activity
mentioned in commit 5dfb55db
The
caps.set_value()is neither intended nor a bug, but it is known. It is one of few (if not the only) adjustment that had to be made in the examples when moving to v2 API. There is no real alternative, but the examples use e.g.namespace GObject_ = gi::repository::GObject(and thenGObject_::Value), which makes it not all that verbose.The other one is a bug with a fix coming up.
I have problems porting to the V2 API, too. It throws creepy errors related to concatenating gi:cstring-s. Is this an incompatibility with Qt headers?
In file included from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/gi.hpp:35, from /usr/src/tdesktop/out/gen/mpris/mpris.hpp:9, from /usr/src/tdesktop/Telegram/lib_base/base/platform/linux/base_system_media_controls_linux.cpp:12: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/object.hpp: In member function ‘R gi::repository::GObject::Object::emit(gi::detail::cstring_v, Args&& ...)’: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/object.hpp:470:67: error: ambiguous overload for ‘operator+’ (operand types are ‘const char [22]’ and ‘const gi::detail::cstring_v’ {aka ‘const gi::detail::cstring_v_d<>’}) 470 | detail::try_throw(std::out_of_range("unknown signal name: " + signal)); | ~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~ | | | | const char [22] const gi::detail::cstring_v {aka const gi::detail::cstring_v_d<>} In file included from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/QByteArray:1, from /usr/src/tdesktop/Telegram/lib_base/base/base_pch.h:8, from /usr/src/tdesktop/out/Telegram/lib_base/CMakeFiles/lib_base.dir/Release/cmake_pch.hxx:5, from <command-line>: /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:593:19: note: candidate: ‘QByteArray operator+(const QByteArray&, const QByteArray&)’ 593 | inline QByteArray operator+(const QByteArray &a1, const QByteArray &a2) | ^~~~~~~~ /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:595:19: note: candidate: ‘QByteArray operator+(QByteArray&&, const QByteArray&)’ 595 | inline QByteArray operator+(QByteArray &&lhs, const QByteArray &rhs) | ^~~~~~~~ /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:605:19: note: candidate: ‘QByteArray operator+(const char*, const QByteArray&)’ 605 | inline QByteArray operator+(const char *a1, const QByteArray &a2) | ^~~~~~~~ In file included from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/QString:1, from /usr/src/tdesktop/Telegram/lib_base/base/base_pch.h:9: /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qstring.h:1310:35: note: candidate: ‘QString operator+(const QString&, const QByteArray&)’ 1310 | QT_ASCII_CAST_WARN inline QString operator+(const QString &s, const QByteArray &ba) | ^~~~~~~~ /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qstring.h:1312:35: note: candidate: ‘QString operator+(QString&&, const QByteArray&)’ 1312 | QT_ASCII_CAST_WARN inline QString operator+(QString &&lhs, const QByteArray &rhs) | ^~~~~~~~ In file included from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/wrap.hpp:5, from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/container.hpp:5, from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/gi.hpp:31: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/string.hpp:674:1: note: candidate: ‘gi::detail::cstring gi::detail::operator+(_string_view, _string_view)’ 674 | operator+(const _string_view x, const _string_view y) noexcept | ^~~~~~~~ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/object.hpp: In member function ‘gi::signal_proxy<void(Base, gi::repository::GObject::ParamSpec)> gi::property_proxy<T, Base>::signal_notify() const’: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/object.hpp:604:44: error: ambiguous overload for ‘operator+’ (operand types are ‘gi::detail::cstring_v’ {aka ‘gi::detail::cstring_v_d<>’} and ‘const gchar*’ {aka ‘const char*’}) 604 | object_, gi::cstring_v("notify::") + pspec_.name_()); | ~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~ | | | | | const gchar* {aka const char*} | gi::detail::cstring_v {aka gi::detail::cstring_v_d<>} /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:593:19: note: candidate: ‘QByteArray operator+(const QByteArray&, const QByteArray&)’ 593 | inline QByteArray operator+(const QByteArray &a1, const QByteArray &a2) | ^~~~~~~~ /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:595:19: note: candidate: ‘QByteArray operator+(QByteArray&&, const QByteArray&)’ 595 | inline QByteArray operator+(QByteArray &&lhs, const QByteArray &rhs) | ^~~~~~~~ /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:597:19: note: candidate: ‘QByteArray operator+(const QByteArray&, const char*)’ 597 | inline QByteArray operator+(const QByteArray &a1, const char *a2) | ^~~~~~~~ /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:599:19: note: candidate: ‘QByteArray operator+(QByteArray&&, const char*)’ 599 | inline QByteArray operator+(QByteArray &&lhs, const char *rhs) | ^~~~~~~~ /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qstring.h:1308:35: note: candidate: ‘QString operator+(const QByteArray&, const QString&)’ 1308 | QT_ASCII_CAST_WARN inline QString operator+(const QByteArray &ba, const QString &s) | ^~~~~~~~ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/string.hpp:674:1: note: candidate: ‘gi::detail::cstring gi::detail::operator+(_string_view, _string_view)’ 674 | operator+(const _string_view x, const _string_view y) noexcept | ^~~~~~~~More creepy errors:
In file included from /opt/rh/gcc-toolset-13/root/usr/include/c++/13/bits/stl_pair.h:60, from /opt/rh/gcc-toolset-13/root/usr/include/c++/13/utility:69, from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qcompilerdetection.h:864, from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qgenericatomic.h:8, from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qatomic_cxx11.h:8, from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbasicatomic.h:8, from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qatomic.h:8, from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qrefcount.h:7, from /usr/local/desktop-app/Qt-6.6.1/include/QtCore/qbytearray.h:8: /opt/rh/gcc-toolset-13/root/usr/include/c++/13/type_traits: In instantiation of ‘struct std::is_convertible<_GHashTable, std::pair<gi::detail::cstring_d<>, gi::detail::cstring_d<> > >’: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/container.hpp:1548:63: required by substitution of ‘template<class InputT, class Check> gi::detail::Collection<_GHashTable, std::pair<char*, char*>, gi::transfer_full_t>::Collection(InputT*, size_t) [with InputT = _GHashTable; Check = <missing>]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/container.hpp:1723:15: required from ‘static CppType gi::detail::Collection<ListType, T, Transfer, Notify, ExtraBase>::_wrap(const ListType*, const ReqTransfer&) [with CppType = gi::detail::Collection<_GHashTable, std::pair<char*, char*>, gi::transfer_full_t>; ReqTransfer = gi::transfer_full_t; typename std::enable_if<(std::is_same<Transfer, ReqTransfer>::value && (! _detail::is_span))>::type* <anonymous> = 0; ListType = _GHashTable; T = std::pair<char*, char*>; Transfer = gi::transfer_full_t; Notify = gi::detail::Notifier<void>; ExtraBase = gi::detail::Container]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/wrap.hpp:134:48: required from ‘TargetType gi::wrap_to(CType, const Transfer&) [with TargetType = detail::Collection<_GHashTable, std::pair<char*, char*>, transfer_full_t>; CType = _GHashTable*; Transfer = transfer_full_t; typename TargetType::_detail::DataType* <anonymous> = 0]’ /usr/src/tdesktop/out/gen/glib/uri_impl.hpp:446:95: required from here /opt/rh/gcc-toolset-13/root/usr/include/c++/13/type_traits:1417:30: error: invalid use of incomplete type ‘struct _GHashTable’ [-fpermissive] 1417 | : public __bool_constant<__is_convertible(_From, _To)> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from /usr/local/include/glib-2.0/glib.h:52, from /usr/local/include/glib-2.0/gobject/gbinding.h:30, from /usr/local/include/glib-2.0/glib-object.h:24, from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/boxed.hpp:6, from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/base.hpp:29, from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/gi.hpp:30: /usr/local/include/glib-2.0/glib/ghash.h:40:16: note: forward declaration of ‘struct _GHashTable’ 40 | typedef struct _GHashTable GHashTable; | ^~~~~~~~~~~ /opt/rh/gcc-toolset-13/root/usr/include/c++/13/type_traits: In instantiation of ‘struct std::is_convertible<_GHashTable, std::pair<gi::detail::cstring_d<>, gi::repository::GLib::Variant> >’: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/container.hpp:1548:63: required by substitution of ‘template<class InputT, class Check> gi::detail::Collection<_GHashTable, std::pair<char*, _GVariant*>, gi::transfer_full_t>::Collection(InputT*, size_t) [with InputT = _GHashTable; Check = <missing>]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/container.hpp:1723:15: required from ‘static CppType gi::detail::Collection<ListType, T, Transfer, Notify, ExtraBase>::_wrap(const ListType*, const ReqTransfer&) [with CppType = gi::detail::Collection<_GHashTable, std::pair<char*, _GVariant*>, gi::transfer_full_t>; ReqTransfer = gi::transfer_full_t; typename std::enable_if<(std::is_same<Transfer, ReqTransfer>::value && (! _detail::is_span))>::type* <anonymous> = 0; ListType = _GHashTable; T = std::pair<char*, _GVariant*>; Transfer = gi::transfer_full_t; Notify = gi::detail::Notifier<void>; ExtraBase = gi::detail::Container]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/wrap.hpp:134:48: required from ‘TargetType gi::wrap_to(CType, const Transfer&) [with TargetType = detail::Collection<_GHashTable, std::pair<char*, _GVariant*>, transfer_full_t>; CType = _GHashTable*; Transfer = transfer_full_t; typename TargetType::_detail::DataType* <anonymous> = 0]’ /usr/src/tdesktop/out/gen/gio/menumodel_impl.hpp:183:107: required from here /opt/rh/gcc-toolset-13/root/usr/include/c++/13/type_traits:1417:30: error: invalid use of incomplete type ‘struct _GHashTable’ [-fpermissive] 1417 | : public __bool_constant<__is_convertible(_From, _To)> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ /usr/local/include/glib-2.0/glib/ghash.h:40:16: note: forward declaration of ‘struct _GHashTable’ 40 | typedef struct _GHashTable GHashTable; | ^~~~~~~~~~~ /opt/rh/gcc-toolset-13/root/usr/include/c++/13/type_traits: In instantiation of ‘struct std::is_convertible<_GHashTable, std::pair<gi::detail::cstring_d<>, gi::repository::Gio::MenuModel> >’: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/container.hpp:1548:63: required by substitution of ‘template<class InputT, class Check> gi::detail::Collection<_GHashTable, std::pair<char*, _GMenuModel*>, gi::transfer_full_t>::Collection(InputT*, size_t) [with InputT = _GHashTable; Check = <missing>]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/container.hpp:1723:15: required from ‘static CppType gi::detail::Collection<ListType, T, Transfer, Notify, ExtraBase>::_wrap(const ListType*, const ReqTransfer&) [with CppType = gi::detail::Collection<_GHashTable, std::pair<char*, _GMenuModel*>, gi::transfer_full_t>; ReqTransfer = gi::transfer_full_t; typename std::enable_if<(std::is_same<Transfer, ReqTransfer>::value && (! _detail::is_span))>::type* <anonymous> = 0; ListType = _GHashTable; T = std::pair<char*, _GMenuModel*>; Transfer = gi::transfer_full_t; Notify = gi::detail::Notifier<void>; ExtraBase = gi::detail::Container]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/wrap.hpp:134:48: required from ‘TargetType gi::wrap_to(CType, const Transfer&) [with TargetType = detail::Collection<_GHashTable, std::pair<char*, _GMenuModel*>, transfer_full_t>; CType = _GHashTable*; Transfer = transfer_full_t; typename TargetType::_detail::DataType* <anonymous> = 0]’ /usr/src/tdesktop/out/gen/gio/menumodel_impl.hpp:209:104: required from here /opt/rh/gcc-toolset-13/root/usr/include/c++/13/type_traits:1417:30: error: invalid use of incomplete type ‘struct _GHashTable’ [-fpermissive] 1417 | : public __bool_constant<__is_convertible(_From, _To)> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ /usr/local/include/glib-2.0/glib/ghash.h:40:16: note: forward declaration of ‘struct _GHashTable’ 40 | typedef struct _GHashTable GHashTable; | ^~~~~~~~~~~ In file included from /usr/src/tdesktop/cmake/external/glib/cppgir/gi/gi.hpp:36: /usr/src/tdesktop/out/gen/gio/dbusinterfaceskeleton.hpp: In instantiation of ‘static constexpr bool gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::TypeInitData::has_definition(const get_info_t*, const SubClass*) [with SubClass = base::Platform::SystemMediaControls::Private::Player; get_info_t = gi::detail::member_type<get_info_tag>]’: /usr/src/tdesktop/cmake/external/glib/cppgir/gi/objectclass.hpp:239:26: required from ‘static constexpr gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::TypeInitData gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::TypeInitData::factory() [with SubClass = base::Platform::SystemMediaControls::Private::Player]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/objectclass.hpp:209:10: required from ‘void (* gi::detail::make_type_init_data())() [with BaseDef = gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef; SubClass = base::Platform::SystemMediaControls::Private::Player; typename std::enable_if<(! std::is_same<SubClass, void>::value)>::type* <anonymous> = 0; type_init_data_factory_t = void (*)()]’ /usr/src/tdesktop/cmake/external/glib/cppgir/gi/objectclass.hpp:577:76: required from ‘gi::detail::ClassTemplate<ClassDef, BaseClass, Interfaces>::ClassTemplate(const SubClass*, GType, gi::detail::cstring_v, const gi::detail::ObjectClass::ClassInitNode&, const gi::repository::GObject::construct_params&, const gi::detail::properties&) [with SubClass = base::Platform::SystemMediaControls::Private::Player; ClassDef = gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef; BaseClass = gi::detail::ObjectClass; Interfaces = {gi::repository::Gio::impl::internal::DBusInterfaceIfaceClassImpl}; GType = long unsigned int; gi::detail::cstring_v = gi::detail::cstring_v_d<>; gi::repository::GObject::construct_params = std::vector<gi::detail::Parameter>; gi::detail::properties = std::map<std::__cxx11::basic_string<char>, std::pair<gi::detail::PropertyBase*, gi::repository::GObject::ParamSpec> >]’ /usr/src/tdesktop/out/gen/gio/dbusinterfaceskeleton.hpp:215:14: required from ‘gi::detail::ClassTemplate<ClassDef, BaseClass, Interfaces>::ClassTemplate(const SubClass*, const gi::repository::GObject::construct_params&, const gi::detail::properties&) [with SubClass = base::Platform::SystemMediaControls::Private::Player; ClassDef = gi::repository::Mpris::impl::internal::MediaPlayer2PlayerSkeletonClassDef; BaseClass = gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClass; Interfaces = {gi::repository::Mpris::impl::internal::MediaPlayer2PlayerIfaceClassImpl}; gi::repository::GObject::construct_params = std::vector<gi::detail::Parameter>; gi::detail::properties = std::map<std::__cxx11::basic_string<char>, std::pair<gi::detail::PropertyBase*, gi::repository::GObject::ParamSpec> >]’ /usr/src/tdesktop/out/gen/mpris/mediaplayer2playerskeleton.hpp:125:14: required from ‘gi::detail::ObjectImpl<ObjectT, ClassT>::ObjectImpl(const SubClass*, const gi::repository::GObject::construct_params&, const gi::detail::properties&) [with SubClass = base::Platform::SystemMediaControls::Private::Player; ObjectT = gi::repository::Mpris::MediaPlayer2PlayerSkeleton; ClassT = gi::repository::Mpris::impl::internal::MediaPlayer2PlayerSkeletonClass; gi::repository::GObject::construct_params = std::vector<gi::detail::Parameter>; gi::detail::properties = std::map<std::__cxx11::basic_string<char>, std::pair<gi::detail::PropertyBase*, gi::repository::GObject::ParamSpec> >]’ /usr/src/tdesktop/Telegram/lib_base/base/platform/linux/base_system_media_controls_linux.cpp:133:19: required from here /usr/src/tdesktop/out/gen/gio/dbusinterfaceskeleton.hpp:266:5: in ‘constexpr’ expansion of ‘gi::detail::Combine<gi::detail::ObjectClass::DefinitionData, gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::TypeInitData>::defines<gi::detail::member_type<gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::TypeInitData::get_info_tag>, base::Platform::SystemMediaControls::Private::Player>(((const gi::detail::member_type<gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::TypeInitData::get_info_tag>*)0), ((const base::Platform::SystemMediaControls::Private::Player*)0))’ /usr/src/tdesktop/out/gen/gio/dbusinterfaceskeleton.hpp:255:3: error: lookup of ‘_check_member_conflict_get_info’ in ‘base::Platform::SystemMediaControls::Private::Player’ is ambiguous 255 | GI_MEMBER_DEFINE(DBusInterfaceSkeletonClass, get_info) | ^~~~~~~~~~~~~~~~ /usr/src/tdesktop/out/gen/gio/dbusinterface.hpp:116:7: note: candidates are: ‘using gi::repository::Gio::impl::internal::DBusInterfaceIfaceDef::_check_member_conflict_get_info = gi::repository::Gio::impl::internal::DBusInterfaceIfaceDef::self’ 116 | using GI_MEMBER_CHECK_CONFLICT(get_info) = self; | ^~~~~~~~~~~~~~~~~~~~~~~~ /usr/src/tdesktop/out/gen/gio/dbusinterfaceskeleton.hpp:172:7: note: ‘using gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::_check_member_conflict_get_info = gi::repository::Gio::impl::internal::DBusInterfaceSkeletonClassDef::self’ 172 | using GI_MEMBER_CHECK_CONFLICT(get_info) = self; | ^~~~~~~~~~~~~~~~~~~~~~~~And it seems something happened to nullable strings?
/usr/src/tdesktop/Telegram/lib_base/base/platform/linux/base_system_media_controls_linux.cpp: In lambda function: /usr/src/tdesktop/Telegram/lib_base/base/platform/linux/base_system_media_controls_linux.cpp:241:80: error: ‘using gi::detail::cstring_v = class gi::detail::cstring_v_d<>’ {aka ‘class gi::detail::cstring_v_d<>’} has no member named ‘value_or’; did you mean ‘value_type’? 241 | LoopStatusToCommand(player().get_loop_status().value_or(""))); | ^~~~~~~~ | value_typeEdited by Ilya FedinAs far as I understand it's supposed to be converted implicitly: https://gitlab.com/mnauw/cppgir/-/blob/master/gi/string.hpp?ref_type=heads#L236-243
And apparently it should then use std::string's operator+ that can concatenate C strings: https://en.cppreference.com/w/cpp/string/basic_string/operator%2BBut it seem to fail to deduce which type is Destination in the template due to Qt's QByteArray that has operator+ for C strings as well
Edited by Ilya FedinAs far as I understand it's supposed to be converted implicitly: https://gitlab.com/mnauw/cppgir/-/blob/master/gi/string.hpp?ref_type=heads#L236-243
How is this supposed to be instantiated implicitly? Correct me if I am wrong, but it will hypothetically require the compiler to try all possible types available in the translation unit as a
Destination.When Qt is not involved, the only operator+ candidate would be
inline cstring operator+(const _string_view x, const _string_view y) noexceptso both the C string (char*) literal and the gi::cstring variable will be converted to a _string_view (using _string_view = cstr<transfer_none_t>;) for concatenation and the result is a gi::cstring. Given that std::out_of_range accepts a std::string, the templated operator Destination will get instantiated into aoperator std::stringso it will get implicitly converted to std::string in the end.Do you have an MWE demonstrating such a templated conversion can be implicitly instantiated? I have an MWE showing it cannot: https://godbolt.org/z/jPGqj1Pvn. Feel free to modify it to illustrate your point.
Not minimal, no. But this cppgir code works if I include it in a file not using Qt headers. Your example lacks the operator+ implementation cppgir has which is important.
Edited by Ilya FedinI'm here to report the bug with cppgir+Qt headers combo, not to argue. You have the cppgir code, you can explore it to find how it works despite it doesn't make sense to you.
Edited by Ilya Fedin
This is indeed due to a surprising incompatibility with Qt headers, as might happen with a conversion function template. So the allowed cases will be restricted (quite) some more to avoid this ambiguity.
The
std::optional<std::string>was introduced asstd::stringcould not express/convey theNULLpointer case. Nowgi::cstringis used as a more tight/simple wrapper of achar*and it also accepts theNULLcase. As such, there is no more need forstd::optional<std::string>(though it still supports some conversion to that case).No idea yet on the
uri_impl.hppcase (?), suffice it to say there is no such error in my builds. Differences in compiler and/or in GLib version (TBD)? The other could be a conflict check on "duplicate members". That is, some situation where inherited interfaces/classes have a conflicting member definition. TheSUBCLASS IMPLEMENTATION APIin documentation elaborates a bit on that.gcc-toolset-13 from Rocky Linux 8 + self-built GLib 2.78.1 + self-built gobject-introspection 1.78.1
Edited by Ilya FedinGI_MEMBER_CHECK_CONFLICTchecks if some method member is defined in multiple superclasses and arranges for hard failure if that is the case. In this case it looks like there is aget_infomember inDBusInterfaceSkeletonClass(Def)andDBusInterfaceIface(Def). This could/should be resolved by manual specification ofDefinitionData, e.g. as in (dummy example) https://gitlab.com/mnauw/cppgir/-/blob/master/examples/gst.cpp?ref_type=heads#L329.I am guessing in this case it might be in
base::Platform::SystemMediaControls::Private::Player? But there seems be user code and then also glib-generated skeleton code in play here (which I do not have at hand here).
mentioned in commit ce6d4c9a
mentioned in commit 59f0ded3
mentioned in commit 13276585
I eventually rolled back to e856d763. I had a queue of VideoFrame, which worked quite well. At the moment, I don't have time to explore why it doesn't work and what changes I have to make. And there is no guarantee it's the last one. Maybe sometime in the future, I will switch to v2 of cppgir.
Thanks for the update, even though a somewhat unfortunate one.
AFAIK, there has only been a minor change in that
CBoxedtype area; theallocatemethod has been rename toallocate_.Besides/beyond that, a
CBoxedtype is and always has been a tricky kind. In this case, e.g.[gst_video_frame_]mapis even more tricky, as the instance parameter is actually (sort-of) an output parameter (though not so annotated). In any case, it would have to be explicitly allocated (using thatallocate_method) before callingmap. And it would also have to be explicitlyunmaped again prior to destruction.I moved on with API v2. It turned out that the problem with VideoFrame was that it was not copyable. I used
boost::lockfree::spsc_queue, which will support non-copyable objects only in Boost 1.86. I don't know why it worked in v1. I changed to storing plain C GstVideoFrame in the queue. map/unmap anyway take care of reference counting. An additional benefit is that GstVideoFrame is now not allocated on the heap.
mentioned in commit 8ab63570
Posting another incompatibility. Before you could have had the following code:
auto bus = pipeline.get_bus(); bus.add_signal_watch(); bus.signal_message().connect([&](Gst::Bus, Gst::Message msg) { // ... }It has to be changed to
auto bus = pipeline.get_bus(); bus.add_signal_watch(); bus.signal_message().connect([&](Gst::Bus, Gst::Message_Ref msg) { // ... }Since many methods return now non-standard strings, you must change all of your instances of
std::format,fmt::print,fmt::format. For example, this worked before:auto oldstatename = Gst::Element::state_get_name(oldstate); auto newstatename = Gst::Element::state_get_name(newstate); auto graph_name = fmt::format("pipeline-{}-{}", oldstatename, newstatename);Now it must be
auto oldstatename = Gst::Element::state_get_name(oldstate); auto newstatename = Gst::Element::state_get_name(newstate); auto graph_name = fmt::format("pipeline-{}-{}", oldstatename.c_str(), newstatename.c_str());
