meta: replace cmake mono-build system with a custom build co-ordinator

every system component now has its own self-contained build system, and a
seed file describing the component and its build system and dependencies.

a new tool, meadow, collects and uses these seed files to build the
components into a full system. meadow also manages the target system root
and a host prefix where toolchain tools are installed to.

the build system has also been updated to use a new $ARCH-rosetta-gcc
compiler, and the patches files necessary to build it have been
added to toolchain/cross-compiler.

lib/libc/CMakeLists.txt

@@ -1,10 +1,12 @@
+cmake_minimum_required(VERSION 3.31)
+project(libc C ASM)
+
 set(source_dirs core malloc io exec)
 
+set(LIBC_STANDALONE FALSE)
 set(public_include_dirs
 	${CMAKE_CURRENT_SOURCE_DIR}/include)
 
-add_subdirectory(runtime)
-
 foreach (dir ${source_dirs})
 	add_subdirectory(${dir})
 	set(sources ${sources} ${component_sources})
@@ -12,22 +14,11 @@ foreach (dir ${source_dirs})
 	set(public_include_dirs ${public_include_dirs} ${component_public_include_dirs})
 endforeach (dir)
 
-rosetta_add_library(SHARED
-	NAME libc
-	PUBLIC_INCLUDE_DIRS ${public_include_dirs}
-	SOURCES ${sources}
-	HEADERS ${headers})
-
-sysroot_add_library(
-	NAME libc
-	HEADER_DIR /usr/include
-	LIB_DIR /usr/lib)
-bsp_add_library(
-	NAME libc
-	LIB_DIR /usr/lib)
-
-target_link_libraries(libc PRIVATE librosetta libxpc-static liblaunch-static interface::fs)
-target_link_libraries(libc PUBLIC libmagenta)
-target_compile_definitions(libc PRIVATE ENABLE_GLOBAL_HEAP=1)
-
-add_subdirectory(pthread)
+add_library(libc SHARED ${sources} ${headers})
+target_include_directories(libc PUBLIC ${public_include_dirs})
+target_link_libraries(libc PRIVATE rosetta libxpc.a liblaunch.a libmagenta.a)
+target_compile_options(libc PRIVATE -ffreestanding -nostdlib)
+target_link_options(libc PRIVATE -ffreestanding -nostdlib)
+target_compile_definitions(libc PRIVATE ENABLE_GLOBAL_HEAP=1 BUILD_SHARED=1)
+set_target_properties(libc PROPERTIES PREFIX "")
+install(TARGETS libc)