Lighttpd

There was also this part I think you missed..

Trying out CMake I see there is not an equivalent of the lua_version
option to select a specific release of Lua.

Both autoconf and meson have this functionality.

Yes, sorry, I overlooked that. I'll see if I can do something similar for cmake.

I figured as much. Thanks.

Another issue I noticed with CMake.

-- found mysql_config: /usr/local/bin/mysql_config
-- Looking for include file mysql.h
-- Looking for include file mysql.h - not found

xconfig(mysql_config MYSQL_LDFLAGS MYSQL_CFLAGS)

set(CMAKE_REQUIRED_INCLUDES /usr/include/mysql)
check_include_files(mysql.h HAVE_MYSQL_H)
set(CMAKE_REQUIRED_INCLUDES)

With the hardcoded path. Instead of using the path that I see would be retrieved via mysql_config.

With the removal years ago of mod_authn_mysql and the requirement to specify --with-mysql or equivalent to build lighttpd modules which depend on mysql, this patch is probably simpler:

--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -333,15 +333,8 @@ endif()

 if(WITH_MYSQL)
        xconfig(mysql_config MYSQL_LDFLAGS MYSQL_CFLAGS)
-
-       set(CMAKE_REQUIRED_INCLUDES /usr/include/mysql)
-       check_include_files(mysql.h HAVE_MYSQL_H)
-       set(CMAKE_REQUIRED_INCLUDES)
-       if(HAVE_MYSQL_H)
-               check_library_exists(mysqlclient mysql_real_connect "" HAVE_MYSQL)
-       endif()
+       check_library_exists(mysqlclient mysql_real_connect "" HAVE_MYSQL)
 else()
-       unset(HAVE_MYSQL_H)
        unset(HAVE_MYSQL)
 endif()

@@ -1003,7 +996,7 @@ if(WITH_MAXMINDDB)
        target_link_libraries(mod_maxminddb maxminddb)
 endif()

-if(HAVE_MYSQL_H AND HAVE_MYSQL)
+if(HAVE_MYSQL)
        add_and_install_library(mod_vhostdb_mysql "mod_vhostdb_mysql.c")
        target_link_libraries(mod_vhostdb_mysql mysqlclient)
        include_directories(/usr/include/mysql)

cmake -DWITH_LUA_VERSION=...

--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -37,6 +37,7 @@ option(WITH_KRB5 "with Kerberos5-support for mod_auth [default: off]")
 option(WITH_LDAP "with LDAP-support for mod_auth mod_vhostdb_ldap [default: off]")
 option(WITH_PAM "with PAM-support for mod_auth [default: off]")
 option(WITH_LUA "with lua for mod_magnet [default: off]")
+option(WITH_LUA_VERSION "specify lua version for mod_magnet")
 # option(WITH_VALGRIND "with internal support for valgrind [default: off]")
 option(WITH_FAM "fam/gamin for reducing number of stat() calls [default: off]")
 option(WITH_LIBDEFLATE "with libdeflate-support for mod_deflate [default: off]")
@@ -757,7 +758,11 @@ else()
 endif()

 if(WITH_LUA)
-       pkg_search_module(LUA REQUIRED lua5.4 lua-5.4 lua5.3 lua-5.3 lua5.2 lua-5.2 lua5.1 lua-5.1 lua)
+       if(WITH_LUA_VERSION)
+               pkg_search_module(LUA REQUIRED ${WITH_LUA_VERSION})
+       else()
+               pkg_search_module(LUA REQUIRED lua5.4 lua-5.4 lua5.3 lua-5.3 lua5.2 lua-5.2 lua5.1 lua-5.1 lua)
+       endif()
        message(STATUS "found lua at: INCDIR: ${LUA_INCLUDE_DIRS} LIBDIR: ${LUA_LIBRARY_DIRS} LDFLAGS: ${LUA_LDFLAGS} CFLAGS: ${LUA_CFLAGS}")
        set(HAVE_LUA_H  1 "Have liblua header")
 else()

That's IMO worse (than fixing the hardcoded path). autoconf will look for libmariadb, then fallback to libmysqlclient and then mysql_config, but the more important part when looking for the libraries is utilizing the pkg-config file. CMake just looks for libmariadb.

The Lua diff works and does as expected. Thanks.

That's IMO worse (than fixing the hardcoded path). autoconf will look for libmariadb, then fallback to libmysqlclient and then mysql_config, but the more important part when looking for the libraries is utilizing the pkg-config file. CMake just looks for libmariadb.

The code in lighttpd src/CMakeLists.txt uses a custom macro named XCONFIG defined earlier in src/CMakeLists.txt.
In the case of mysql, the macro looks for mysql_config and uses that. mysql_config is present on my system and configurd to use mariadb.
Maybe the XCONFIG macro could be extended if not sufficient? (Patches welcome.)

I think you're referring to the line
check_library_exists(mysqlclient mysql_real_connect "" HAVE_MYSQL)
which did not change in the path other than leading whitespace indenting, so the limitation has not changed.

My Fedora Linux system provides the following for compatibility

/usr/lib64/libmysqlclient_r.so -> libmariadb.so.3
/usr/lib64/libmysqlclient.so -> libmariadb.so.3

Can CMake use ${MYSQL_LDFLAGS} returned from mysql_config --libs when checking for mysql_real_connect?
Alternatively, is the test largely redundant due to the existence (or not) of mysql_config?

Would you prefer this?

--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -334,7 +334,9 @@ endif()

 if(WITH_MYSQL)
        xconfig(mysql_config MYSQL_LDFLAGS MYSQL_CFLAGS)
-       check_library_exists(mysqlclient mysql_real_connect "" HAVE_MYSQL)
+       if(MYSQL_LDFLAGS)
+               set(HAVE_MYSQL TRUE)
+       endif()
 else()
        unset(HAVE_MYSQL)
 endif()

With that it finds mysql_config and then does nothing with MYSQL_CFLAGS / MYSQL_LDFLAGS; the module is enabled but the builds fails.

Oh, also staring at the CMake file I noticed this line..

        include_directories(/usr/include/mysql)

Sigh. More historical hard-coding of mysqlclient.

--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1003,8 +1005,8 @@ endif()

 if(HAVE_MYSQL)
        add_and_install_library(mod_vhostdb_mysql "mod_vhostdb_mysql.c")
-       target_link_libraries(mod_vhostdb_mysql mysqlclient)
-       include_directories(/usr/include/mysql)
+       add_target_properties(mod_vhostdb_mysql COMPILE_FLAGS ${MYSQL_CFLAGS})
+       target_link_libraries(mod_vhostdb_mysql ${MYSQL_LDFLAGS})
 endif()

 if(HAVE_PGSQL)

Thank you. The updated bit for CFLAGS handling does the trick.