cmake: add CMake Config-based dependency detection

After limiting `find_package()`/`find_dependency()` calls to curl local Find modules via the `MODULES` keyword, it became possible to detect dependencies via CMake Configs from within those local Find modules, by calling `find_package()` again with the `CONFIG` keyword. This patch implements this. Then maps detection results to the result variables and curl-specific imported targets the rest of the build expects. Also honor recently introduced `*_USE_STATIC_LIBS` (experimental) flags to map to the static target when requested. This adds CMake Configs as an alternative to the existing `pkg-config` and `find_path()`/`find_library()` auto-detection methods. Enabled by default for MSVC, outside vcpkg and when not cross-building. To enable for other cases, or override the default, you can use `-DCURL_USE_CMAKECONFIG=ON` or `OFF`. When enabled, Config detection happens after `pkg-config` and before `find_path()`/`find_library()`. Using CMake's built-in options, you may also manually point to the absolute directory holding Config files: `Libssh2_DIR`, `MbedTLS_DIR`, `NGHTTP2_DIR`, `NGHTTP3_DIR`, `NGTCP2_DIR` v1.19.0+ (with non-fork OpenSSL only), `Zstd_DIR` v1.4.5+ E.g. `-DMbedTLS_DIR=/path/to/mbedtls/lib/cmake/MbedTLS` These dependencies typically need to be built with CMake to support this. Tagged as experimental. Refs: #20013 #19156 #19117 https://github.com/curl/curl/pull/20784#issuecomment-3984318492 Depends-on: fad1ebaecc #20840 Follow-up to 91e06fde1b #20784 Follow-up to 26c39d8df1 #20015 Closes #20814
2026-04-11 12:01:42 +08:00 · 2026-03-03 14:48:32 +01:00 · 2026-03-03 14:48:32 +01:00 · 8fce3e17e6
commit 8fce3e17e6
parent aef8fd00c8
11 changed files with 142 additions and 29 deletions
--- a/.github/workflows/configure-vs-cmake.yml
+++ b/.github/workflows/configure-vs-cmake.yml
@ -52,7 +52,7 @@ jobs:
          mkdir bld-am && cd bld-am && ../configure --enable-static=no --with-openssl --without-libpsl

      - name: 'run cmake'
-        run: cmake -B bld-cm -DCURL_WERROR=ON -DCURL_USE_LIBPSL=OFF
+        run: cmake -B bld-cm -DCURL_WERROR=ON -DCURL_USE_CMAKECONFIG=OFF -DCURL_USE_LIBPSL=OFF

      - name: 'configure log'
        run: cat bld-am/config.log 2>/dev/null || true
@ -101,7 +101,7 @@ jobs:

      - name: 'run cmake'
        run: |
-          cmake -B bld-cm -DCURL_WERROR=ON -DCURL_USE_LIBPSL=OFF -DCURL_DISABLE_LDAP=ON \
+          cmake -B bld-cm -DCURL_WERROR=ON -DCURL_USE_CMAKECONFIG=OFF -DCURL_USE_LIBPSL=OFF -DCURL_DISABLE_LDAP=ON \
            -DCMAKE_C_COMPILER_TARGET="$(uname -m | sed 's/arm64/aarch64/')-apple-darwin$(uname -r)" \
            -DCURL_USE_LIBSSH2=OFF -DUSE_APPLE_SECTRUST=ON

@ -148,7 +148,7 @@ jobs:

      - name: 'run cmake'
        run: |
-          cmake -B bld-cm -DCURL_WERROR=ON -DCURL_USE_SCHANNEL=ON -DCURL_USE_LIBPSL=OFF \
+          cmake -B bld-cm -DCURL_WERROR=ON -DCURL_USE_CMAKECONFIG=OFF -DCURL_USE_SCHANNEL=ON -DCURL_USE_LIBPSL=OFF \
            -DCMAKE_SYSTEM_NAME=Windows \
            -DCMAKE_C_COMPILER_TARGET="${TRIPLET}" \
            -DCMAKE_C_COMPILER="${TRIPLET}-gcc"
--- a/CMake/FindLibssh2.cmake
+++ b/CMake/FindLibssh2.cmake
@ -37,11 +37,15 @@

 set(_libssh2_pc_requires "libssh2")

-if(CURL_USE_PKGCONFIG AND
-   NOT DEFINED LIBSSH2_INCLUDE_DIR AND
+if(NOT DEFINED LIBSSH2_INCLUDE_DIR AND
   NOT DEFINED LIBSSH2_LIBRARY)
-  find_package(PkgConfig QUIET)
-  pkg_check_modules(_libssh2 ${_libssh2_pc_requires})
+  if(CURL_USE_PKGCONFIG)
+    find_package(PkgConfig QUIET)
+    pkg_check_modules(_libssh2 ${_libssh2_pc_requires})
+  endif()
+  if(NOT _libssh2_FOUND AND CURL_USE_CMAKECONFIG)
+    find_package(libssh2 CONFIG QUIET)
+  endif()
 endif()

 if(_libssh2_FOUND AND _libssh2_INCLUDE_DIRS)
@ -55,6 +59,16 @@ if(_libssh2_FOUND AND _libssh2_INCLUDE_DIRS)
    set(_libssh2_LIBRARIES    "${_libssh2_STATIC_LIBRARIES}")
  endif()
  message(STATUS "Found Libssh2 (via pkg-config): ${_libssh2_INCLUDE_DIRS} (found version \"${LIBSSH2_VERSION}\")")
+elseif(libssh2_CONFIG)
+  set(Libssh2_FOUND TRUE)
+  set(LIBSSH2_FOUND TRUE)
+  set(LIBSSH2_VERSION ${libssh2_VERSION})
+  if(LIBSSH2_USE_STATIC_LIBS)
+    set(_libssh2_LIBRARIES libssh2::libssh2_static)
+  else()
+    set(_libssh2_LIBRARIES libssh2::libssh2)
+  endif()
+  message(STATUS "Found Libssh2 (via CMake Config): ${libssh2_CONFIG} (found version \"${LIBSSH2_VERSION}\")")
 else()
  find_path(LIBSSH2_INCLUDE_DIR NAMES "libssh2.h")
  if(LIBSSH2_USE_STATIC_LIBS)
--- a/CMake/FindMbedTLS.cmake
+++ b/CMake/FindMbedTLS.cmake
@ -45,13 +45,17 @@ endif()

 set(_mbedtls_pc_requires "mbedtls" "mbedx509" "mbedcrypto")

-if(CURL_USE_PKGCONFIG AND
-   NOT DEFINED MBEDTLS_INCLUDE_DIR AND
+if(NOT DEFINED MBEDTLS_INCLUDE_DIR AND
   NOT DEFINED MBEDTLS_LIBRARY AND
   NOT DEFINED MBEDX509_LIBRARY AND
   NOT DEFINED MBEDCRYPTO_LIBRARY)
-  find_package(PkgConfig QUIET)
-  pkg_check_modules(_mbedtls ${_mbedtls_pc_requires})
+  if(CURL_USE_PKGCONFIG)
+    find_package(PkgConfig QUIET)
+    pkg_check_modules(_mbedtls ${_mbedtls_pc_requires})
+  endif()
+  if(NOT _mbedtls_FOUND AND CURL_USE_CMAKECONFIG)
+    find_package(MbedTLS CONFIG QUIET)
+  endif()
 endif()

 if(_mbedtls_FOUND)
@ -65,6 +69,17 @@ if(_mbedtls_FOUND)
    set(_mbedtls_LIBRARIES    "${_mbedtls_STATIC_LIBRARIES}")
  endif()
  message(STATUS "Found MbedTLS (via pkg-config): ${_mbedtls_INCLUDE_DIRS} (found version \"${MBEDTLS_VERSION}\")")
+elseif(MbedTLS_CONFIG)
+  set(MbedTLS_FOUND TRUE)
+  set(MBEDTLS_FOUND TRUE)
+  set(MBEDTLS_VERSION ${MbedTLS_VERSION})
+  if(MBEDTLS_VERSION GREATER_EQUAL 4.0.0)
+    set(_mbedtls_LIBRARIES MbedTLS::tfpsacrypto)
+  else()
+    set(_mbedtls_LIBRARIES MbedTLS::mbedcrypto)
+  endif()
+  list(APPEND _mbedtls_LIBRARIES MbedTLS::mbedx509 MbedTLS::mbedtls)
+  message(STATUS "Found MbedTLS (via CMake Config): ${MbedTLS_CONFIG} (found version \"${MBEDTLS_VERSION}\")")
 else()
  set(_mbedtls_pc_requires "")  # Depend on pkg-config only when found via pkg-config

--- a/CMake/FindNGHTTP2.cmake
+++ b/CMake/FindNGHTTP2.cmake
@ -37,11 +37,15 @@

 set(_nghttp2_pc_requires "libnghttp2")

-if(CURL_USE_PKGCONFIG AND
-   NOT DEFINED NGHTTP2_INCLUDE_DIR AND
+if(NOT DEFINED NGHTTP2_INCLUDE_DIR AND
   NOT DEFINED NGHTTP2_LIBRARY)
-  find_package(PkgConfig QUIET)
-  pkg_check_modules(_nghttp2 ${_nghttp2_pc_requires})
+  if(CURL_USE_PKGCONFIG)
+    find_package(PkgConfig QUIET)
+    pkg_check_modules(_nghttp2 ${_nghttp2_pc_requires})
+  endif()
+  if(NOT _nghttp2_FOUND AND CURL_USE_CMAKECONFIG)
+    find_package(nghttp2 CONFIG QUIET)
+  endif()
 endif()

 if(_nghttp2_FOUND)
@ -54,6 +58,15 @@ if(_nghttp2_FOUND)
    set(_nghttp2_LIBRARIES    "${_nghttp2_STATIC_LIBRARIES}")
  endif()
  message(STATUS "Found NGHTTP2 (via pkg-config): ${_nghttp2_INCLUDE_DIRS} (found version \"${NGHTTP2_VERSION}\")")
+elseif(nghttp2_CONFIG)
+  set(NGHTTP2_FOUND TRUE)
+  set(NGHTTP2_VERSION ${nghttp2_VERSION})
+  if(NGHTTP2_USE_STATIC_LIBS)
+    set(_nghttp2_LIBRARIES nghttp2::nghttp2_static)
+  else()
+    set(_nghttp2_LIBRARIES nghttp2::nghttp2)
+  endif()
+  message(STATUS "Found NGHTTP2 (via CMake Config): ${nghttp2_CONFIG} (found version \"${NGHTTP2_VERSION}\")")
 else()
  find_path(NGHTTP2_INCLUDE_DIR NAMES "nghttp2/nghttp2.h")
  if(NGHTTP2_USE_STATIC_LIBS)
--- a/CMake/FindNGHTTP3.cmake
+++ b/CMake/FindNGHTTP3.cmake
@ -37,11 +37,15 @@

 set(_nghttp3_pc_requires "libnghttp3")

-if(CURL_USE_PKGCONFIG AND
-   NOT DEFINED NGHTTP3_INCLUDE_DIR AND
+if(NOT DEFINED NGHTTP3_INCLUDE_DIR AND
   NOT DEFINED NGHTTP3_LIBRARY)
-  find_package(PkgConfig QUIET)
-  pkg_check_modules(_nghttp3 ${_nghttp3_pc_requires})
+  if(CURL_USE_PKGCONFIG)
+    find_package(PkgConfig QUIET)
+    pkg_check_modules(_nghttp3 ${_nghttp3_pc_requires})
+  endif()
+  if(NOT _nghttp3_FOUND AND CURL_USE_CMAKECONFIG)
+    find_package(nghttp3 CONFIG QUIET)
+  endif()
 endif()

 if(_nghttp3_FOUND)
@ -54,6 +58,15 @@ if(_nghttp3_FOUND)
    set(_nghttp3_LIBRARIES    "${_nghttp3_STATIC_LIBRARIES}")
  endif()
  message(STATUS "Found NGHTTP3 (via pkg-config): ${_nghttp3_INCLUDE_DIRS} (found version \"${NGHTTP3_VERSION}\")")
+elseif(nghttp3_CONFIG)
+  set(NGHTTP3_FOUND TRUE)
+  set(NGHTTP3_VERSION ${nghttp3_VERSION})
+  if(NGHTTP3_USE_STATIC_LIBS)
+    set(_nghttp3_LIBRARIES nghttp3::nghttp3_static)
+  else()
+    set(_nghttp3_LIBRARIES nghttp3::nghttp3)
+  endif()
+  message(STATUS "Found NGHTTP3 (via CMake Config): ${nghttp3_CONFIG} (found version \"${NGHTTP3_VERSION}\")")
 else()
  find_path(NGHTTP3_INCLUDE_DIR NAMES "nghttp3/nghttp3.h")
  if(NGHTTP3_USE_STATIC_LIBS)
--- a/CMake/FindNGTCP2.cmake
+++ b/CMake/FindNGTCP2.cmake
@ -74,12 +74,22 @@ if(_ngtcp2_crypto_backend)
 endif()

 set(_tried_pkgconfig FALSE)
-if(CURL_USE_PKGCONFIG AND
-   NOT DEFINED NGTCP2_INCLUDE_DIR AND
+if(NOT DEFINED NGTCP2_INCLUDE_DIR AND
   NOT DEFINED NGTCP2_LIBRARY)
-  find_package(PkgConfig QUIET)
-  pkg_check_modules(_ngtcp2 ${_ngtcp2_pc_requires})
-  set(_tried_pkgconfig TRUE)
+  if(CURL_USE_PKGCONFIG)
+    find_package(PkgConfig QUIET)
+    pkg_check_modules(_ngtcp2 ${_ngtcp2_pc_requires})
+    set(_tried_pkgconfig TRUE)
+  endif()
+  if(NOT _ngtcp2_FOUND AND CURL_USE_CMAKECONFIG)
+    find_package(ngtcp2 CONFIG QUIET)
+    # Skip using it if the crypto library target is not available
+    if(ngtcp2_CONFIG AND
+       NOT TARGET ngtcp2::${_crypto_library_lower}_static AND
+       NOT TARGET ngtcp2::${_crypto_library_lower})
+      unset(ngtcp2_CONFIG)
+    endif()
+  endif()
 endif()

 if(_ngtcp2_FOUND)
@ -92,6 +102,15 @@ if(_ngtcp2_FOUND)
    set(_ngtcp2_LIBRARIES    "${_ngtcp2_STATIC_LIBRARIES}")
  endif()
  message(STATUS "Found NGTCP2 (via pkg-config): ${_ngtcp2_INCLUDE_DIRS} (found version \"${NGTCP2_VERSION}\")")
+elseif(ngtcp2_CONFIG)
+  set(NGTCP2_FOUND TRUE)
+  set(NGTCP2_VERSION ${ngtcp2_VERSION})
+  if(NGTCP2_USE_STATIC_LIBS)
+    set(_ngtcp2_LIBRARIES ngtcp2::ngtcp2_static ngtcp2::${_crypto_library_lower}_static)
+  else()
+    set(_ngtcp2_LIBRARIES ngtcp2::ngtcp2 ngtcp2::${_crypto_library_lower})
+  endif()
+  message(STATUS "Found NGTCP2 (via CMake Config): ${ngtcp2_CONFIG} (found version \"${NGTCP2_VERSION}\")")
 else()
  find_path(NGTCP2_INCLUDE_DIR NAMES "ngtcp2/ngtcp2.h")
  if(NGTCP2_USE_STATIC_LIBS)
--- a/CMake/FindZstd.cmake
+++ b/CMake/FindZstd.cmake
@ -46,11 +46,21 @@ endif()

 set(_zstd_pc_requires "libzstd")

-if(CURL_USE_PKGCONFIG AND
-   NOT DEFINED ZSTD_INCLUDE_DIR AND
+if(NOT DEFINED ZSTD_INCLUDE_DIR AND
   NOT DEFINED ZSTD_LIBRARY)
-  find_package(PkgConfig QUIET)
-  pkg_check_modules(_zstd ${_zstd_pc_requires})
+  if(CURL_USE_PKGCONFIG)
+    find_package(PkgConfig QUIET)
+    pkg_check_modules(_zstd ${_zstd_pc_requires})
+  endif()
+  if(NOT _zstd_FOUND AND CURL_USE_CMAKECONFIG)
+    find_package(Zstd CONFIG QUIET)
+    # Skip using if older than v1.4.5
+    if(Zstd_CONFIG AND
+       NOT TARGET zstd::libzstd_static AND
+       NOT TARGET zstd::libzstd_shared)
+      unset(Zstd_CONFIG)
+    endif()
+  endif()
 endif()

 if(_zstd_FOUND)
@ -64,6 +74,17 @@ if(_zstd_FOUND)
    set(_zstd_LIBRARIES    "${_zstd_STATIC_LIBRARIES}")
  endif()
  message(STATUS "Found Zstd (via pkg-config): ${_zstd_INCLUDE_DIRS} (found version \"${ZSTD_VERSION}\")")
+elseif(Zstd_CONFIG)
+  set(ZSTD_FOUND TRUE)
+  set(ZSTD_VERSION ${Zstd_VERSION})
+  if(ZSTD_USE_STATIC_LIBS)
+    set(_zstd_LIBRARIES zstd::libzstd_static)
+  elseif(TARGET zstd::libzstd)
+    set(_zstd_LIBRARIES zstd::libzstd)  # v1.5.6+
+  else()
+    set(_zstd_LIBRARIES zstd::libzstd_shared)
+  endif()
+  message(STATUS "Found Zstd (via CMake Config): ${Zstd_CONFIG} (found version \"${ZSTD_VERSION}\")")
 else()
  find_path(ZSTD_INCLUDE_DIR NAMES "zstd.h")
  if(ZSTD_USE_STATIC_LIBS)
--- a/CMake/curl-config.in.cmake
+++ b/CMake/curl-config.in.cmake
@ -23,6 +23,8 @@
 ###########################################################################
@PACKAGE_INIT@

+option(CURL_USE_CMAKECONFIG "Enable detecting @PROJECT_NAME@ dependencies via CMake Config. Default: @CURL_USE_CMAKECONFIG@"
+  "@CURL_USE_CMAKECONFIG@")
 option(CURL_USE_PKGCONFIG "Enable pkg-config to detect @PROJECT_NAME@ dependencies. Default: @CURL_USE_PKGCONFIG@"
  "@CURL_USE_PKGCONFIG@")

--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -385,6 +385,14 @@ if(WIN32)
  endif()
 endif()

+# Override to force-disable or force-enable the use of CMake Configs.
+if(MSVC AND NOT VCPKG_TOOLCHAIN AND NOT CMAKE_CROSSCOMPILING)
+  set(_curl_use_cmakeconfig_default ON)
+else()
+  set(_curl_use_cmakeconfig_default OFF)
+endif()
+option(CURL_USE_CMAKECONFIG "Enable detecting dependencies via CMake Config" ${_curl_use_cmakeconfig_default})
+
 # Override to force-disable or force-enable the use of pkg-config.
 if((UNIX AND NOT ANDROID AND (NOT APPLE OR CMAKE_SYSTEM_NAME STREQUAL "Darwin")) OR
   VCPKG_TOOLCHAIN OR
@ -2325,6 +2333,7 @@ if(NOT CURL_DISABLE_INSTALL)
  #   TARGETS_EXPORT_NAME
  #   CURL_SUPPORTED_FEATURES_LIST
  #   CURL_SUPPORTED_PROTOCOLS_LIST
+  #   CURL_USE_CMAKECONFIG
  #   CURL_USE_PKGCONFIG
  #   HAVE_BROTLI
  #   HAVE_GSSAPI
--- a/docs/INSTALL-CMAKE.md
+++ b/docs/INSTALL-CMAKE.md
@ -347,6 +347,7 @@ Details via CMake
 ## Dependencies

 - `CURL_BROTLI`:                            Use brotli (`ON`, `OFF` or `AUTO`). Default: `AUTO`
+- `CURL_USE_CMAKECONFIG`:                   Enable detecting dependencies via CMake Config. Default: `ON` for MSVC (except under vcpkg), if not cross-compiling. (experimental)
 - `CURL_USE_GNUTLS`:                        Enable GnuTLS for SSL/TLS. Default: `OFF`
 - `CURL_USE_GSASL`:                         Use libgsasl. Default: `OFF`
 - `CURL_USE_GSSAPI`:                        Use GSSAPI implementation. Default: `OFF`
@ -383,6 +384,11 @@ Details via CMake
 - `ZLIB_INCLUDE_DIR`:                       Absolute path to zlib include directory.
 - `ZLIB_LIBRARY`:                           Absolute path to `zlib` library.
 - `ZLIB_USE_STATIC_LIBS`:                   Look for static `zlib` library (requires CMake v3.24).
+- `<PackageName>_DIR`:                      Absolute path to `<PackageName>` CMake Config directory where `*.cmake` files reside. Used when `CURL_USE_CMAKECONFIG` is enabled.
+                                            `<PackageName>` may be:
+                                            `Libssh2`, `MbedTLS`, `NGHTTP2`, `NGHTTP3`,
+                                            `NGTCP2` 1.19.0+ (with non-fork OpenSSL only),
+                                            `Zstd` 1.4.5+.

 ## Dependency options (tools)

--- a/tests/cmake/CMakeLists.txt
+++ b/tests/cmake/CMakeLists.txt
@ -92,7 +92,8 @@ elseif(TEST_INTEGRATION_MODE STREQUAL "ExternalProject")
    URL "${FROM_ARCHIVE}" URL_HASH "SHA256=${FROM_HASH}"
    ${_download_extract_timestamp}
    PREFIX "${CMAKE_BINARY_DIR}/curl-external"
-    CMAKE_ARGS "-DCMAKE_INSTALL_PREFIX=${_curl_install_dir}" -DBUILD_SHARED_LIBS=OFF -DCURL_USE_LIBPSL=OFF -DCURL_USE_PKGCONFIG=OFF
+    CMAKE_ARGS "-DCMAKE_INSTALL_PREFIX=${_curl_install_dir}" -DBUILD_SHARED_LIBS=OFF -DCURL_USE_LIBPSL=OFF
+      -DCURL_USE_CMAKECONFIG=OFF -DCURL_USE_PKGCONFIG=OFF
      -DCURL_ENABLE_SSL=OFF -DCURL_ENABLE_SSL=OFF -DCURL_DISABLE_LDAP=ON -DCURL_USE_LIBSSH2=OFF -DUSE_NGHTTP2=OFF
      -DCURL_BROTLI=OFF -DCURL_ZLIB=OFF -DCURL_ZSTD=OFF -DUSE_LIBIDN2=OFF -DENABLE_IPV6=OFF
      ${CURL_TEST_OPTS}