Cleanup lv_port_linux

[etag4048]

Split backends into separate files, adding the capability of linking to multiple backends at once and select which one to use at runtime. This also avoids EXCESSIVE conditional compilation soup in main.c - it is irritating for a tool that I use daily.

The next step is to find a clean way of configuring CMAKE or GNU make based on the options found
in lv_conf.h

[kisvegabor]

Thank you!

I made a quick review, mainly to find formatting and naming issues.

[etag4048]

@kisvegabor I've adjusted the code.

[etag4048]

For the failing CI see this : #74

[shaleh]

Parsing lv_conf.h for cmake could be a hassle. What if instead you made lv_conf.h.in and wrote out the desired values based on inputs to the initial cmake setup command? -DUSE_WAYLAND for instance.

Edited. Nevermind. I see EDGEMTech ran into the same thing I did with scripts/backend_conf not being run in the correct place. They fixed it by forcing the path in the script. I posted over in #57 (comment) that the ideal fix is passing in WORKING_DIRECTORY to execute_process.

This same idea could be replicated. Read out the value and update the CMake logic. I thought this could get ugly because I was thinking of running a compiled program with #ifdefs from the header.

[shaleh]

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 19c08dd..321b0b3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,11 +1,10 @@
 cmake_minimum_required(VERSION 3.10)
 project(lvgl)
 
-
-set(CONF_PATH "${PROJECT_SOURCE_DIR}/lv_conf.h")
-
 foreach(BACKEND_NAME "SDL" "LINUX_DRM" "LINUX_FBDEV" "X11" "WAYLAND" "OPENGLES" "EVDEV")
-    execute_process(COMMAND "${PROJECT_SOURCE_DIR}/scripts/backend_conf.sh" ${BACKEND_NAME} ${CONF_PATH} OUTPUT_VARIABLE IS_BACKEND_ENABLED)
+    execute_process(COMMAND "scripts/backend_conf.sh" ${BACKEND_NAME}
+                    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+                    OUTPUT_VARIABLE IS_BACKEND_ENABLED)
     set("LV_USE_${BACKEND_NAME}" ${IS_BACKEND_ENABLED})
 endforeach()
 
diff --git a/scripts/backend_conf.sh b/scripts/backend_conf.sh
index ce1c721..750a3a3 100755
--- a/scripts/backend_conf.sh
+++ b/scripts/backend_conf.sh
@@ -1,15 +1,2 @@
 #!/bin/sh
-
-# Temporary solution called by CMake to determine what features
-# are enabled in lv_conf.h - This will replaced by a solution that can also
-# be used with GNU make or CMake
-# It also currently doesn't handle an alternate location for lv_conf.h
-# other than the one in repository
-
-if test $# -ne 2
-then
-    echo "usage: backend_conf.sh FEATURE_NAME lv_conf_path"
-    exit 1
-fi
-
-grep "^#define LV_USE_$1" "$2" | sed 's/#define //g' | awk '{ if ($2=="1") { printf "ON" } else { printf "OFF" }}'
+grep "^#define LV_USE_$1" lv_conf.h | sed 's/#define //g' | awk '{ if ($2=="1") { printf "ON" } else { printf "OFF" }}'

[etag4048]

@shaleh
I posted over in #57 (comment) that the ideal fix is passing in WORKING_DIRECTORY to execute_process.

Ok thanks for suggestion