cmake: create and install pkg-config files

[yegorich]

Automatically create and install *.pc files for selected components.

PocoFoundation.pc
PocoNet.pc
PocoUtil.pc
etc.

[yegorich]

This is just an RFC to agree on *.pc file names, what should go into Requires field etc.

Fixes #2037

[zosrothko]

That's ok for me. The only point is that on Windows, cmake should install the Poco binaries (lib, dll, pdb & includes) at the same place as the MSI installer.

[aleks-f]

@zosrothko is MSI documented somewhere?

[zosrothko]

@aleks-f No, that's missing. the directory structure has 2 majors subdivisions: the VS version and the Poco version like for the x86 architecture

C:\Program Files (x86)
          | Poco
                   | VS2017
                            | 1.8.1
                                   | bin
                                   | doc
                                   | inc
                                   | lib

and for the x64 architecture

C:\Program Files
          | Poco
                   | VS2017
                            | 1.8.1
                                   | bin
                                   | doc
                                   | inc
                                   | lib

This could be changed if needed

[yegorich]

So far I have created following *.pc.in files:

PocoCppUnit.pc.in
PocoCrypto.pc.in
PocoEncodings.pc.in
PocoFoundation.pc.in
PocoJSON.pc.in
PocoMongoDB.pc.in
PocoNet.pc.in
PocoNetSSL.pc.in
PocoPDF.pc.in
PocoRedis.pc.in
PocoSevenZip.pc.in
PocoSQL.pc.in
PocoUtil.pc.in
PocoXML.pc.in
PocoZip.pc.in

Following components are missing:

SQLite, ODBC and Co
CppParser
PocoDoc
PageCompiler
File2Page

so basically all components should have own *.pc.in file? Or some of them don't make sense?

What about NetSSL? Is it sufficient to have PocoNetSSL or should I also add PocoNetSSL_Win (I'm working with Linux only)?

As for Database libs, they won't be handled in the main CMakeLists.txt. Should I place related commands in their own CMakeLists.txt files?

[Bjoe]

Some questions...

[Bjoe]

@yegorich You created following *.pc.in files ... but I see only two files on the pull request :-)

[yegorich]

@Bjoe I haven't pushed v2, so you don't see the new *.pc.in files. I just wanted to get the answers to my questions prior to pushing v2.

[Bjoe]

I just wanted to get the answers to my questions

@yegorich ok.
For PocoNetSSL_Win ... I don't know if this make sense. I think on windows pkg-config is not really used there or?

As for Database libs, they won't be handled in the main CMakeLists.txt. Should I place related commands in their own CMakeLists.txt files?

Hm sorry I didn't get you...

[zosrothko]

@Bjoe I think on windows pkg-config is not really used ==>correct, but it could be used for the Cygwin platform which is a subsystem running on top of Windows

[yegorich]

@zosrothko as for Windows, should I install *.pc files to the same directory as cmake files? I.e. pkgconfig?

if (WIN32)
  set(PocoConfigPackageLocation "cmake")
else()
  set(PocoConfigPackageLocation "lib/cmake/${PROJECT_NAME}")
endif()

configure_file(cmake/${PROJECT_NAME}Config.cmake.in "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}/${PROJECT_NAME}Config.cmake" @ONLY)
install(
    FILES
        ${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}/${PROJECT_NAME}Config.cmake
        ${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}/${PROJECT_NAME}ConfigVersion.cmake
    DESTINATION
        "${PocoConfigPackageLocation}"
    COMPONENT
        Devel
)

[Bjoe]

@yegorich Cygwin is like a "Linux shell environment in Windows" I think, install the *.pc like under Linux/Unix...

[yegorich]

I've pushed v2. Now with SQLite, MySQL and PostgreSQL *.pc files.

[Bjoe]

I rebased your branch to the develop HEAD from friday and fixed the merge conflicts. When all is fine I will merge your branch in the next days. Thanks for your contribution.