cmake: use pkg_check_modules() for GnuTLS

Remove the local cmake file and associated hacks used to manage GnuTLS.
This gives us less build-system glue code and makes it easier to enforce
a minimum version for GnuTLS.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>

CMakeLists.txt

@@ -211,11 +211,9 @@ include_directories(${LIBGCRYPT_INCLUDE_DIRS})
 list(APPEND EXTRA_LIBS ${LIBGCRYPT_LDFLAGS})
 
 # Check for GnuTLS
-find_package(GnuTLS REQUIRED)
-string(REGEX REPLACE "/[^/]*$" "" GNUTLS_LIBRARY_PATH "${GNUTLS_LIBRARY}")
-include_directories(${GNUTLS_INCLUDE_PATH})
-set(CMAKE_C_LINK_FLAGS "${CMAKE_C_LINK_FLAGS} -L${GNUTLS_LIBRARY_PATH}")
-list(APPEND EXTRA_LIBS gnutls)
+pkg_check_modules(GNUTLS REQUIRED gnutls)
+include_directories(${GNUTLS_INCLUDE_DIRS})
+list(APPEND EXTRA_LIBS ${GNUTLS_LDFLAGS})
 
 # Check for zlib
 find_package(ZLIB REQUIRED)

cmake/FindGnuTLS.cmake

@@ -1,75 +0,0 @@
-#
-# Copyright (C) 2003-2024 Sébastien Helleu <flashcode@flashtux.org>
-# Copyright (C) 2009 Emmanuel Bouthenot <kolter@openics.org>
-#
-# This file is part of WeeChat, the extensible chat client.
-#
-# WeeChat is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 3 of the License, or
-# (at your option) any later version.
-#
-# WeeChat is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with WeeChat.  If not, see <https://www.gnu.org/licenses/>.
-#
-
-# - Find GnuTLS
-# This module finds if libgnutls is installed and determines where
-# the include files and libraries are.
-#
-# This code sets the following variables:
-#
-#  GNUTLS_INCLUDE_PATH = path to where <gnutls/gnutls.h> can be found
-#  GNUTLS_LIBRARY = path to where libgnutls.so* can be found
-#  GNUTLS_CFLAGS = cflags to use to compile
-#  GNUTLS_LDFLAGS = ldflags to use to compile
-
-if(GNUTLS_INCLUDE_PATH AND GNUTLS_LIBRARY)
-  # Already in cache, be silent
-  set(GNUTLS_FIND_QUIETLY TRUE)
-endif()
-
-find_program(PKG_CONFIG_EXECUTABLE NAMES pkg-config)
-
-execute_process(COMMAND ${PKG_CONFIG_EXECUTABLE} --variable=prefix gnutls
-  OUTPUT_VARIABLE GNUTLS_PREFIX
-)
-
-execute_process(COMMAND ${PKG_CONFIG_EXECUTABLE} --cflags gnutls
-  OUTPUT_VARIABLE GNUTLS_CFLAGS
-)
-string(REGEX REPLACE "[\r\n]" "" GNUTLS_CFLAGS "${GNUTLS_CFLAGS}")
-
-execute_process(COMMAND ${PKG_CONFIG_EXECUTABLE} --libs gnutls
-  OUTPUT_VARIABLE GNUTLS_LDFLAGS
-)
-string(REGEX REPLACE "[\r\n]" "" GNUTLS_LDFLAGS "${GNUTLS_LDFLAGS}")
-
-set(GNUTLS_POSSIBLE_INCLUDE_PATH "${GNUTLS_PREFIX}/include")
-set(GNUTLS_POSSIBLE_LIB_DIR "${GNUTLS_PREFIX}/lib")
-
-find_path(GNUTLS_INCLUDE_PATH
-  NAMES gnutls/gnutls.h
-  PATHS GNUTLS_POSSIBLE_INCLUDE_PATH
-)
-
-find_library(GNUTLS_LIBRARY
-  NAMES gnutls
-  PATHS GNUTLS_POSSIBLE_LIB_DIR
-)
-
-if(NOT GNUTLS_INCLUDE_PATH OR NOT GNUTLS_LIBRARY)
-  message(FATAL_ERROR "GnuTLS was not found")
-endif()
-
-mark_as_advanced(
-  GNUTLS_INCLUDE_PATH
-  GNUTLS_LIBRARY
-  GNUTLS_CFLAGS
-  GNUTLS_LDFLAGS
-)

src/core/CMakeLists.txt

@@ -87,8 +87,6 @@ else()
   check_symbol_exists(backtrace "execinfo.h" HAVE_BACKTRACE)
 endif()
 
-include_directories(${GNUTLS_INCLUDE_PATH})
-
 if(ENABLE_ZSTD)
   include_directories(${LIBZSTD_INCLUDE_DIRS})
 endif()

src/plugins/irc/CMakeLists.txt

@@ -53,8 +53,7 @@ set_target_properties(irc PROPERTIES PREFIX "")
 
 set(LINK_LIBS)
 
-include_directories(${GNUTLS_INCLUDE_PATH})
-list(APPEND LINK_LIBS ${GNUTLS_LIBRARY})
+list(APPEND LINK_LIBS ${GNUTLS_LDFLAGS})
 
 list(APPEND LINK_LIBS ${LIBGCRYPT_LDFLAGS})
 

src/plugins/relay/CMakeLists.txt

@@ -61,8 +61,7 @@ set_target_properties(relay PROPERTIES PREFIX "")
 
 set(LINK_LIBS)
 
-include_directories(${GNUTLS_INCLUDE_PATH})
-list(APPEND LINK_LIBS ${GNUTLS_LIBRARY})
+list(APPEND LINK_LIBS ${GNUTLS_LDFLAGS})
 
 list(APPEND LINK_LIBS ${LIBGCRYPT_LDFLAGS})