vcpkg compliant CMake example project for shared/static cross-platform builds?

[SamuelMarks]

Given (essentially) this directory layout:

|-- CMakeLists.txt
|-- libcurl-simple-https
|   |-- CMakeLists.txt
|   |-- curl_simple_https.c
|   `-- curl_simple_https.h
`-- vcpkg.json

For reuse as boilerplate across my decent number of C projects, I took https://gitlab.kitware.com/cmake/cmake/-/blob/master/Help/guide/tutorial/Complete :

• replaced literal names with variables;
• removed functionality irrelevant to my purposes;
• added stronger use strict style guards:
  • set(CMAKE_C_STANDARD 90)
  • set(CMAKE_C_VISIBILITY_PRESET hidden)
  • set(CMAKE_VISIBILITY_INLINES_HIDDEN YES)
  • "$<${gcc_like}:$<BUILD_INTERFACE:-Wall;-Wextra;-Wshadow;-Wformat=2;-Wunused;-pedantic>>"
  • "$<${msvc}:$<BUILD_INTERFACE:-W3;-WX;-Zi;-permissive->>"
• generated export headers with GenerateExportHeader;
• set separate Source_Files and Header_Files vars [with source_groups] for installation [and IDE assist]
• added the INSTALL(EXPORT lines.

Unfortunately where I've got up to so far isn't far enough…

CMakeLists.txt

# control where the static and shared libraries are built so that on windows
# we don't need to tinker with the path to run the executable
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}")
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}")
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${PROJECT_BINARY_DIR}")

if (NOT DEFINED CMAKE_BUILD_TYPE)
    if (DEFINED CMAKE_RC_FLAGS_RELEASE)
        set(CMAKE_BUILD_TYPE "Release")
    else ()
        set(CMAKE_BUILD_TYPE "Debug")
    endif ()
endif (NOT DEFINED CMAKE_BUILD_TYPE)

if (CMAKE_SYSTEM_NAME STREQUAL "Windows")
    set(INSTALL_LIB_DESTINATION "bin")
    if (CMAKE_BUILD_TYPE STREQUAL "Debug")
        set(INSTALL_LIB_DESTINATION "${CMAKE_BUILD_TYPE}/${INSTALL_LIB_DESTINATION}")
    endif (CMAKE_BUILD_TYPE STREQUAL "Debug")
else()
    set(INSTALL_LIB_DESTINATION "lib")
endif (CMAKE_SYSTEM_NAME STREQUAL "Windows")

libcurl-simple-https/CMakeLists.txt:

set(installable_libs
        "${LIBRARY_NAME}" "${PROJECT_NAME}_compiler_flags" "${PROJECT_NAME}_utils" "${PROJECT_NAME}_google_auth")
if (TARGET "${DEPENDANT_LIBRARY}")
  list(APPEND installable_libs "${DEPENDANT_LIBRARY}")
endif (TARGET "${DEPENDANT_LIBRARY}")
install(TARGETS ${installable_libs}
        DESTINATION "${INSTALL_LIB_DESTINATION}"
        EXPORT "${LIBRARY_NAME}Targets")
install(FILES "${_export_file}" "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}_configure.h" ${Header_Files}
        DESTINATION "include")
install(EXPORT "${LIBRARY_NAME}Targets" DESTINATION "share/${LIBRARY_NAME}")

All my attempts at creating simple C projects that were subsequently offered as vcpkg ports:

• https://github.com/SamuelMarks/curl-simple-https
• https://github.com/offscale/cauthflow (see its CMakeLists.txt I tried setting RUNTIME/LIBRARY/ARCHIVE DESTINATION and different global OUTPUT_DIRECTORY)
• https://github.com/offscale/c89randomstr (works but is header-only)
• https://github.com/offscale/c89stringutils (works but is header-only)

What am I doing wrong? - Is there an example project boilerplate I can follow? - Even the oft-copied file(REMOVE_RECURSE "${CURRENT_PACKAGES_DIR}/debug") in my portfile.cmake seems wrong…

Thanks for suggestions

[Neumann-A]

• Use https://cmake.org/cmake/help/latest/module/GNUInstallDirs.html
• Use install(FILES) with the TYPE signature
• Use install(EXPORT) to generate targets.cmake
• use https://cmake.org/cmake/help/latest/module/CMakePackageConfigHelpers.html

Don't do

• target based compiler interface helpers: "${PROJECT_NAME}_compiler_flags"
• don't set CMAKE_BUILD_TYPE. leave this up to the user.
• no need for config aware INSTALL_LIB_DESTINATION. (vcpkg automatically runs for both buildtypes and adjust the prefix so you are not helping here)

Notes:

• generated export headers with GenerateExportHeader; Might require a vcpkg_string_replace to hardcode static vs shared builds. (Mostly static because shared is the common default )

file(REMOVE_RECURSE "${CURRENT_PACKAGES_DIR}/debug")

This is required by header only ports. Alternatively you can set VCPKG_BUILD_TYPE in the portfile to release but you need to make sure that your exported targets are aware of that and configuration independent. .

[SamuelMarks]

Ok thanks. I think I've got the hang of that… maybe, just updated my PR: #22917

[SamuelMarks]

@Neumann-A No, I am still getting:

The following dlls were found in /lib or /debug/lib. Please move them to /bin or /debug/bin, respectively.

    D:/packages/libcurl-simple-https_x86-windows/lib/libcurl-simple-https.dll

Mismatching number of debug and release binaries. Found 0 for debug but 1 for release.
Debug binaries


Release binaries

    D:/packages/libcurl-simple-https_x86-windows/lib/libcurl-simple-https.lib

Debug binaries were not found

[Neumann-A]

Your

install(TARGETS ${installable_libs}
        DESTINATION "${INSTALL_LIB_DESTINATION}"
        EXPORT "${LIBRARY_NAME}Targets")

is not enough to install targets/libraries/executables correctly.
You can try without DESTINATION

install(TARGETS ${installable_libs} EXPORT "${LIBRARY_NAME}Targets")

and hope cmake does the right thing or use
ARCHIVE|LIBRARY|RUNTIME

install(TARGETS ${installable_libs} EXPORT "${LIBRARY_NAME}Targets"
          ARCHIVE DESTINATION <libdir>
          LIBRARY DESTINATION <libdir>
          RUNTIME DESTINATION <bindir>
          )

Please watch https://www.youtube.com/watch?v=m0DwB4OvDXk (the install stuff is around 30 min)

[SamuelMarks]

Updated both ports [libcurl-simple-https, cauthflow] with open PRs. Didn't fix the bug. Will watch that YouTube video later tonight.

[Neumann-A]

cmake_minimum_required(VERSION 3.0) .... but that is not the issue here.

It cannot work if you still delete the /debug folder in the portfile.cmake .....dlls are now in /bin and not in /lib.....