build: drop WIN32 exclusion from http_output, webserver, and metrics gates

Rely solely on MINIMAL_BUILD and EMSCRIPTEN as semantic guards instead of explicit platform checks. MSVC builds are unaffected since  CompilerFlags.cmake forces MINIMAL_BUILD=ON, keeping these features  disabled. Non-MSVC Windows toolchains (MinGW, clang) can now build with http_output if curl and OpenSSL are available.

Signed-off-by: Leonardo Grasso <me@leonardograsso.com>

CMakeLists.txt

@@ -175,18 +175,14 @@ include(njson)
 # yaml-cpp
 include(yaml-cpp)
 
-if(NOT WIN32
-   AND NOT APPLE
-   AND NOT MINIMAL_BUILD
-   AND NOT EMSCRIPTEN
-)
+if(NOT MINIMAL_BUILD AND NOT EMSCRIPTEN)
 	# OpenSSL
 	include(openssl)
 
 	# libcurl
 	include(curl)
 
-	# todo(jasondellaluce,rohith-raju): support webserver for non-linux builds too cpp-httlib
+	# cpp-httplib
 	include(cpp-httplib)
 endif()
 
@@ -202,14 +198,6 @@ include(valijson)
 if(USE_GPERFTOOLS)
 	include(gperftools)
 endif()
-if(NOT MINIMAL_BUILD)
-	if(NOT WIN32
-	   AND NOT APPLE
-	   AND NOT EMSCRIPTEN
-	)
-		include(cares)
-	endif()
-endif()
 
 # Installation
 if(WIN32)

cmake/modules/cares.cmake

@@ -1,78 +0,0 @@
-# SPDX-License-Identifier: Apache-2.0
-#
-# Copyright (C) 2023 The Falco Authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
-# in compliance with the License. You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software distributed under the License
-# is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
-# or implied. See the License for the specific language governing permissions and limitations under
-# the License.
-#
-
-option(USE_BUNDLED_CARES "Enable building of the bundled c-ares" ${USE_BUNDLED_DEPS})
-
-if(CARES_INCLUDE)
-	# we already have c-ares
-elseif(NOT USE_BUNDLED_CARES)
-	find_path(CARES_INCLUDE NAMES cares/ares.h ares.h)
-	find_library(CARES_LIB NAMES cares)
-	if(CARES_INCLUDE AND CARES_LIB)
-		message(STATUS "Found c-ares: include: ${CARES_INCLUDE}, lib: ${CARES_LIB}")
-	else()
-		message(FATAL_ERROR "Couldn't find system c-ares")
-	endif()
-else()
-	if(BUILD_SHARED_LIBS)
-		set(CARES_LIB_SUFFIX ${CMAKE_SHARED_LIBRARY_SUFFIX})
-		set(CARES_STATIC_OPTION "Off")
-	else()
-		set(CARES_LIB_SUFFIX ${CMAKE_STATIC_LIBRARY_SUFFIX})
-		set(CARES_STATIC_OPTION "On")
-	endif()
-	set(CARES_SRC "${PROJECT_BINARY_DIR}/c-ares-prefix/src/c-ares")
-	set(CARES_INCLUDE "${CARES_SRC}/include/")
-	set(CARES_LIB "${CARES_SRC}/lib/libcares${CARES_LIB_SUFFIX}")
-
-	if(NOT TARGET c-ares)
-		message(STATUS "Using bundled c-ares in '${CARES_SRC}'")
-		ExternalProject_Add(
-			c-ares
-			PREFIX "${PROJECT_BINARY_DIR}/c-ares-prefix"
-			URL "https://github.com/c-ares/c-ares/releases/download/v1.33.1/c-ares-1.33.1.tar.gz"
-			URL_HASH "SHA256=06869824094745872fa26efd4c48e622b9bd82a89ef0ce693dc682a23604f415"
-			BUILD_IN_SOURCE 1
-			CMAKE_ARGS -DCMAKE_POLICY_DEFAULT_CMP0091:STRING=NEW
-					   -DCMAKE_MSVC_RUNTIME_LIBRARY=${CMAKE_MSVC_RUNTIME_LIBRARY}
-					   -DCMAKE_INSTALL_LIBDIR=lib
-					   -DCARES_SHARED=${BUILD_SHARED_LIBS}
-					   -DCARES_STATIC=${CARES_STATIC_OPTION}
-					   -DCARES_STATIC_PIC=${ENABLE_PIC}
-					   -DCARES_BUILD_TOOLS=Off
-					   -DCARES_INSTALL=Off
-					   -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}
-			BUILD_BYPRODUCTS ${CARES_INCLUDE} ${CARES_LIB}
-			INSTALL_COMMAND ""
-		)
-		install(
-			FILES "${CARES_LIB}"
-			DESTINATION "${CMAKE_INSTALL_LIBDIR}/${LIBS_PACKAGE_NAME}"
-			COMPONENT "libs-deps"
-		)
-		install(
-			DIRECTORY "${CARES_INCLUDE}"
-			DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/${LIBS_PACKAGE_NAME}"
-			COMPONENT "libs-deps"
-		)
-	endif()
-
-endif()
-
-if(NOT TARGET c-ares)
-	add_custom_target(c-ares)
-endif()
-
-include_directories("${CARES_INCLUDE}")

userspace/engine/falco_utils.cpp

@@ -22,7 +22,7 @@ limitations under the License.
 #include <libsinsp/utils.h>
 
 #include <re2/re2.h>
-#if defined(__linux__) and !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
+#if !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
 #include <openssl/evp.h>
 #endif
 #include <cstring>
@@ -136,7 +136,7 @@ uint64_t parse_prometheus_interval(std::string interval_str) {
 	return interval;
 }
 
-#if defined(__linux__) and !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
+#if !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
 std::string calculate_file_sha256sum(const std::string& filename) {
 	std::ifstream file(filename, std::ios::binary);
 	if(!file.is_open()) {

userspace/engine/falco_utils.h

@@ -26,7 +26,7 @@ limitations under the License.
 namespace falco::utils {
 uint64_t parse_prometheus_interval(std::string interval_str);
 
-#if defined(__linux__) and !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
+#if !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
 std::string calculate_file_sha256sum(const std::string& filename);
 #endif
 

userspace/falco/CMakeLists.txt

@@ -83,22 +83,16 @@ if(NOT WIN32)
 	target_sources(falco_application PRIVATE outputs_program.cpp outputs_syslog.cpp)
 endif()
 
-if(CMAKE_SYSTEM_NAME MATCHES "Linux" AND NOT MINIMAL_BUILD)
+if(NOT EMSCRIPTEN AND NOT MINIMAL_BUILD)
 	target_sources(falco_application PRIVATE outputs_http.cpp falco_metrics.cpp webserver.cpp)
 
-	list(APPEND FALCO_INCLUDE_DIRECTORIES FALCO_INCLUDE_DIRECTORIES "${OPENSSL_INCLUDE_DIR}"
-		 "${CARES_INCLUDE}"
-	)
+	list(APPEND FALCO_INCLUDE_DIRECTORIES FALCO_INCLUDE_DIRECTORIES "${OPENSSL_INCLUDE_DIR}")
 
-	if(TARGET c-ares)
-		list(APPEND FALCO_DEPENDENCIES c-ares)
-	endif()
-
-	if(CMAKE_SYSTEM_NAME MATCHES "Linux" AND USE_BUNDLED_CURL)
+	if(USE_BUNDLED_CURL)
 		list(APPEND FALCO_DEPENDENCIES curl)
 	endif()
 
-	list(APPEND FALCO_LIBRARIES httplib::httplib "${CURL_LIBRARIES}" "${CARES_LIB}")
+	list(APPEND FALCO_LIBRARIES httplib::httplib "${CURL_LIBRARIES}")
 endif()
 
 if(EMSCRIPTEN)

userspace/falco/app/actions/load_rules_files.cpp

@@ -82,7 +82,7 @@ falco::app::run_result falco::app::actions::load_rules_files(falco::app::state&
 		if(res->has_warnings()) {
 			falco_logger::log(falco_logger::level::WARNING, res->as_string(true, rc) + "\n");
 		}
-#if defined(__linux__) and !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
+#if !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
 		s.config->m_loaded_rules_filenames_sha256sum.insert(
 		        {filename, falco::utils::calculate_file_sha256sum(filename)});
 #endif

userspace/falco/app/actions/start_webserver.cpp

@@ -17,7 +17,7 @@ limitations under the License.
 
 #include "actions.h"
 
-#if defined(__linux__) && !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
+#if !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
 #include "webserver.h"
 #endif
 
@@ -25,7 +25,7 @@ using namespace falco::app;
 using namespace falco::app::actions;
 
 falco::app::run_result falco::app::actions::start_webserver(falco::app::state& state) {
-#if defined(__linux__) && !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
+#if !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
 	if(state.is_capture_mode() || !state.config->m_webserver_enabled) {
 		return run_result::ok();
 	}
@@ -50,7 +50,7 @@ falco::app::run_result falco::app::actions::start_webserver(falco::app::state& s
 }
 
 falco::app::run_result falco::app::actions::stop_webserver(falco::app::state& state) {
-#if defined(__linux__) && !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
+#if !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
 	if(state.is_capture_mode() || !state.config->m_webserver_enabled) {
 		return run_result::ok();
 	}

userspace/falco/app/state.h

@@ -23,7 +23,7 @@ limitations under the License.
 #include "restart_handler.h"
 #include "../configuration.h"
 #include "../stats_writer.h"
-#if defined(__linux__) && !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
+#if !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
 #include "../webserver.h"
 #endif
 
@@ -109,7 +109,7 @@ struct state {
 	// Helper responsible for watching of handling hot application restarts
 	std::shared_ptr<restart_handler> restarter;
 
-#if defined(__linux__) && !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
+#if !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
 	falco_webserver webserver;
 #endif
 	// Set by start_webserver to start prometheus metrics

userspace/falco/configuration.cpp

@@ -211,7 +211,7 @@ void falco_configuration::merge_config_files(const std::string &config_name,
 		}
 	}
 
-#if defined(__linux__) and !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
+#if !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
 	for(auto &filename : m_loaded_configs_filenames) {
 		m_loaded_configs_filenames_sha256sum.insert(
 		        {filename, falco::utils::calculate_file_sha256sum(filename)});

userspace/falco/falco_metrics.cpp

@@ -115,7 +115,7 @@ std::string falco_metrics::falco_to_text_prometheus(
 	        "falco",
 	        {{"version", FALCO_VERSION}});
 
-#if defined(__linux__) and !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
+#if !defined(MINIMAL_BUILD) and !defined(__EMSCRIPTEN__)
 	// Note that the rule counter metrics are retrieved from the state, not from any inspector
 	// Distinguish between config and rules files using labels, following Prometheus best
 	// practices: https://prometheus.io/docs/practices/naming/#labels

userspace/falco/falco_outputs.cpp

@@ -28,7 +28,7 @@ limitations under the License.
 #include "outputs_program.h"
 #include "outputs_syslog.h"
 #endif
-#if defined(__linux__) && !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
+#if !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
 #include "outputs_http.h"
 #endif
 
@@ -93,7 +93,7 @@ void falco_outputs::add_output(const falco::outputs::config &oc) {
 		oo = std::make_unique<falco::outputs::output_syslog>();
 	}
 #endif
-#if defined(__linux__) && !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
+#if !defined(__EMSCRIPTEN__) && !defined(MINIMAL_BUILD)
 	else if(oc.name == "http") {
 		oo = std::make_unique<falco::outputs::output_http>();
 	}