build: cmake multi-pkg-config detection improvements (brotli, ldap, mbedtls)

Apply downstream patch from the vcpkg project:

- cmake/FindBrotli: streamline detecting multiple pkg-config modules.
  Add `libbrotlicommon` to `Requires.private` in `libcurl.pc`.

Apply the above idea to the rest of multi-module dependencies:

- cmake/FindMbedTLS: streamline detecting multiple pkg-config modules
  Add `mbedx509`, `mbedcrypto` to `Requires.private` in `libcurl.pc`.

- cmake/FindLDAP: streamline detecting multiple pkg-config modules

And sync these changes with autotools, and add `libbrotlicommon`,
`mbedx509`, `mbedcrypto` to `Requires.private`.

Co-authored-by: Kai Pastor
Ref: https://github.com/microsoft/vcpkg/pull/43819

Closes #16479

CMake/FindBrotli.cmake

@@ -39,24 +39,18 @@
 # - `BROTLI_CFLAGS`:         Required compiler flags.
 # - `BROTLI_VERSION`:        Version of brotli.
 
-set(BROTLI_PC_REQUIRES "libbrotlidec")
+set(BROTLI_PC_REQUIRES "libbrotlidec" "libbrotlicommon")  # order is significant: brotlidec then brotlicommon
 
 if(CURL_USE_PKGCONFIG AND
    NOT DEFINED BROTLI_INCLUDE_DIR AND
    NOT DEFINED BROTLICOMMON_LIBRARY AND
    NOT DEFINED BROTLIDEC_LIBRARY)
   find_package(PkgConfig QUIET)
-  pkg_check_modules(BROTLI "libbrotlicommon")
-  pkg_check_modules(BROTLIDEC ${BROTLI_PC_REQUIRES})
+  pkg_check_modules(BROTLI ${BROTLI_PC_REQUIRES})
 endif()
 
-if(BROTLI_FOUND AND BROTLIDEC_FOUND)
+if(BROTLI_FOUND)
   set(Brotli_FOUND TRUE)
-  list(APPEND BROTLIDEC_LIBRARIES ${BROTLI_LIBRARIES})  # order is significant: brotlidec then brotlicommon
-  list(REVERSE BROTLIDEC_LIBRARIES)
-  list(REMOVE_DUPLICATES BROTLIDEC_LIBRARIES)
-  list(REVERSE BROTLIDEC_LIBRARIES)
-  set(BROTLI_LIBRARIES ${BROTLIDEC_LIBRARIES})
   string(REPLACE ";" " " BROTLI_CFLAGS "${BROTLI_CFLAGS}")
   message(STATUS "Found Brotli (via pkg-config): ${BROTLI_INCLUDE_DIRS} (found version \"${BROTLI_VERSION}\")")
 else()

CMake/FindLDAP.cmake

@@ -39,7 +39,7 @@
 # - `LDAP_CFLAGS`:        Required compiler flags.
 # - `LDAP_VERSION`:       Version of ldap.
 
-set(LDAP_PC_REQUIRES "ldap")
+set(LDAP_PC_REQUIRES "ldap" "lber")
 
 if(CURL_USE_PKGCONFIG AND
    NOT DEFINED LDAP_INCLUDE_DIR AND
@@ -47,14 +47,9 @@ if(CURL_USE_PKGCONFIG AND
    NOT DEFINED LDAP_LBER_LIBRARY)
   find_package(PkgConfig QUIET)
   pkg_check_modules(LDAP ${LDAP_PC_REQUIRES})
-  pkg_check_modules(LDAP_LBER "lber")
 endif()
 
-if(LDAP_FOUND AND LDAP_LBER_FOUND)
-  list(APPEND LDAP_LIBRARIES ${LDAP_LBER_LIBRARIES})
-  list(REVERSE LDAP_LIBRARIES)
-  list(REMOVE_DUPLICATES LDAP_LIBRARIES)
-  list(REVERSE LDAP_LIBRARIES)
+if(LDAP_FOUND)
   string(REPLACE ";" " " LDAP_CFLAGS "${LDAP_CFLAGS}")
   message(STATUS "Found LDAP (via pkg-config): ${LDAP_INCLUDE_DIRS} (found version \"${LDAP_VERSION}\")")
 else()

CMake/FindMbedTLS.cmake

@@ -46,7 +46,7 @@ if(DEFINED MBEDTLS_INCLUDE_DIRS AND NOT DEFINED MBEDTLS_INCLUDE_DIR)
   unset(MBEDTLS_INCLUDE_DIRS)
 endif()
 
-set(MBEDTLS_PC_REQUIRES "mbedtls")
+set(MBEDTLS_PC_REQUIRES "mbedtls" "mbedx509" "mbedcrypto")
 
 if(CURL_USE_PKGCONFIG AND
    NOT DEFINED MBEDTLS_INCLUDE_DIR AND
@@ -55,16 +55,10 @@ if(CURL_USE_PKGCONFIG AND
    NOT DEFINED MBEDCRYPTO_LIBRARY)
   find_package(PkgConfig QUIET)
   pkg_check_modules(MBEDTLS ${MBEDTLS_PC_REQUIRES})
-  pkg_check_modules(MBEDX509 "mbedx509")
-  pkg_check_modules(MBEDCRYPTO "mbedcrypto")
 endif()
 
-if(MBEDTLS_FOUND AND MBEDX509_FOUND AND MBEDCRYPTO_FOUND)
+if(MBEDTLS_FOUND)
   set(MbedTLS_FOUND TRUE)
-  list(APPEND MBEDTLS_LIBRARIES ${MBEDX509_LIBRARIES} ${MBEDCRYPTO_LIBRARIES})
-  list(REVERSE MBEDTLS_LIBRARIES)
-  list(REMOVE_DUPLICATES MBEDTLS_LIBRARIES)
-  list(REVERSE MBEDTLS_LIBRARIES)
   string(REPLACE ";" " " MBEDTLS_CFLAGS "${MBEDTLS_CFLAGS}")
   message(STATUS "Found MbedTLS (via pkg-config): ${MBEDTLS_INCLUDE_DIRS} (found version \"${MBEDTLS_VERSION}\")")
 else()

configure.ac

@@ -1522,7 +1522,7 @@ if test X"$OPT_BROTLI" != Xno; then
         AC_MSG_NOTICE([Added $DIR_BROTLI to CURL_LIBRARY_PATH])
       fi
     fi
-    LIBCURL_PC_REQUIRES_PRIVATE="$LIBCURL_PC_REQUIRES_PRIVATE libbrotlidec"
+    LIBCURL_PC_REQUIRES_PRIVATE="$LIBCURL_PC_REQUIRES_PRIVATE libbrotlidec libbrotlicommon"
   else
     dnl no brotli, revert back to clean variables
     LDFLAGS=$CLEANLDFLAGS

m4/curl-mbedtls.m4

@@ -104,7 +104,7 @@ if test "x$OPT_MBEDTLS" != xno; then
       fi
       dnl FIXME: Enable when mbedTLS was detected via pkg-config
       if false; then
-        LIBCURL_PC_REQUIRES_PRIVATE="$LIBCURL_PC_REQUIRES_PRIVATE mbedtls"
+        LIBCURL_PC_REQUIRES_PRIVATE="$LIBCURL_PC_REQUIRES_PRIVATE mbedtls mbedx509 mbedcrypto"
       fi
     fi