Makefile / library path modifications to make M1 building work (#1570)

See koreader/koreader#8797

Makefile.defs

@@ -8,6 +8,7 @@ else
 endif
 
 UNAME:=$(shell uname -s)
+UNAME_ARCH:=$(shell uname -m)
 
 # use MAKEFILE_DIR instead of CURDIR for variables that are exported through -include
 MAKEFILE_DIR=$(dir $(abspath $(lastword $(MAKEFILE_LIST))))
@@ -189,8 +190,14 @@ endif
 
 ifneq (,$(filter $(UNAME), Darwin))
 	export DARWINHOST=1
+	ifneq (,$(filter $(UNAME_ARCH), arm64))
+		export DARWIN_AARCH64_HOST=1
+	endif
 	ifdef EMULATE_READER
 		export DARWIN=1
+		ifdef DARWIN_AARCH64_HOST
+			export DARWIN_AARCH64=1
+		endif
 	endif
 endif
 
@@ -500,6 +507,16 @@ ifdef MACOS
 	HOST_ARCH:=-mtune=generic
 endif
 
+ifdef DARWIN_AARCH64_HOST
+# At the moment of writing, apple-m1 is the lowest common denominator for Apple silicon chips. Should work for M2 as well
+	HOST_ARCH:=-mcpu=apple-m1
+	BREW_PREFIX:=$(shell command brew --prefix 2>/dev/null)
+	ifneq (,$(BREW_PREFIX))
+		export DARWIN_AARCH64_HOST_CFLAG:=-I$(BREW_PREFIX)/include
+		export DARWIN_AARCH64_HOST_LDFLAG:=-L$(BREW_PREFIX)/lib
+	endif
+endif
+
 # Anything below GCC 6 gets to be forcefully switched to decent standards, because some of our deps require C11 & C++11 support.
 # NOTE: Technically, this also means we require Clang >= 3.2, but that should more or less hold true on our end, because that's truly ancient.
 # Tests heavily inspired from Linux's build system ;).

Makefile.third

@@ -610,7 +610,7 @@ $(OPENSSL_LIB) $(OPENSSL_DIR): $(THIRDPARTY_DIR)/openssl/*.*
 		-DRANLIB="$(RANLIB)" \
 		-DCHOST="$(CHOST)" \
 		$(if $(ANDROID),-DNDKABI=$(NDKABI),) \
-		-DCONFIG_SCRIPT="$(if $(EMULATE_READER),$(if $(DARWIN),Configure darwin64-x86_64-cc,config),Configure $(if $(WIN32),mingw,))" \
+		-DCONFIG_SCRIPT="$(if $(EMULATE_READER),$(if $(DARWIN),Configure $(if $(DARWIN_AARCH64),darwin64-arm64-cc,darwin64-x86_64-cc),config),Configure $(if $(WIN32),mingw,))" \
 		$(CURDIR)/$(THIRDPARTY_DIR)/openssl && \
 		$(CMAKE_MAKE_PROGRAM) $(CMAKE_MAKE_PROGRAM_FLAGS)
 

ffi/SDL2_0.lua

@@ -25,6 +25,7 @@ local SDL = util.ffiLoadCandidates{
     -- this unfortunately needs to be written in full due to the . in the name
     "libSDL2-2.0.so",
     "libSDL2-2.0.so.0",
+    util.KO_DYLD_PREFIX .. "/lib/libSDL2.dylib",
 }
 
 -- Some features (like SDL_GameControllerRumble) may require a minimum version

ffi/util.lua

@@ -60,10 +60,27 @@ int WideCharToMultiByte(
 );
 ]]
 
+local getlibprefix = function()
+    -- Apple M1 homebrew installs libraries outside of default searchpaths,
+    -- and dyld environment variables are sip-protected on MacOS, cf. https://github.com/Homebrew/brew/issues/13481#issuecomment-1181592842
+    local libprefix = os.getenv("KO_DYLD_PREFIX")
+
+    if not libprefix then
+        local std_out = io.popen("brew --prefix", "r")
+            if std_out then
+                libprefix = std_out:read("*line")
+                std_out:close()
+            end
+    end
+
+    return libprefix
+end
+
 require("ffi/posix_h")
 
 local util = {}
 
+util.KO_DYLD_PREFIX = getlibprefix()
 
 if ffi.os == "Windows" then
     util.gettime = function()
@@ -634,7 +651,7 @@ function util.haveSDL2()
     if haveSDL2 == nil then
         local candidates
         if ffi.os == "OSX" then
-            candidates = {"libs/libSDL2.dylib", "SDL2"}
+            candidates = {"libs/libSDL2.dylib", "SDL2", util.KO_DYLD_PREFIX .. "/lib/libSDL2.dylib"}
         else
             candidates = {"SDL2", "libSDL2-2.0.so", "libSDL2-2.0.so.0"}
         end

thirdparty/glib/CMakeLists.txt

@@ -69,8 +69,8 @@ endif()
 if(NOT DEFINED ENV{DARWIN})
     set(LDFLAGS "${LDFLAGS} -Wl,-rpath-link,${ZLIB_DIR}/lib -Wl,-rpath-link,${LIBFFI_DIR}/.libs -Wl,-rpath-link,${BINARY_DIR}/gmodule/.libs")
 else()
-    set(CFLAGS "-I/usr/local/opt/gettext/include ${CFLAGS}")
-    set(LDFLAGS "${LDFLAGS} -L/usr/local/opt/gettext/lib -L${LIBICONV_DIR}/lib -L${ZLIB_DIR}/lib -L${LIBFFI_DIR}/.libs -L${BINARY_DIR}/gmodule/.libs")
+    set(CFLAGS "-I/usr/local/opt/gettext/include $ENV{DARWIN_AARCH64_HOST_CFLAG} ${CFLAGS}")
+    set(LDFLAGS "${LDFLAGS} -L/usr/local/opt/gettext/lib $ENV{DARWIN_AARCH64_HOST_LDFLAG} -L${LIBICONV_DIR}/lib -L${ZLIB_DIR}/lib -L${LIBFFI_DIR}/.libs -L${BINARY_DIR}/gmodule/.libs")
 endif()
 
 set(CFG_OPTS "${CFG_OPTS} CFLAGS=\"${CFLAGS}\" LDFLAGS=\"${LDFLAGS}\" ${HOST_OPTS}")