seperate host &* cart for wasi-sdk cart compile

.gitignore

@@ -1,2 +1,2 @@
 .DS_Store
-build
+build/

README.md

@@ -5,8 +5,7 @@ This should allow passing pointers back & forth between host & cart.
 ## build
 
 ```
-emcmake cmake -B build -GNinja
-cmake --build build
+./build.sh
 ```
 
 ## host
@@ -16,5 +15,5 @@ This is a web-based host, compiled with emscripten. It has it's memory exported.
 
 ## cart
 
-This is user-code, and must import it's memory (which comes from host.)
+This is user-code, and must import it's memory (which comes from host.) It is built with wasi-sdk, for a very low-level no-frills wasm.
 

build.sh

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+mkdir -p build
+
+cd host
+emcmake cmake -B build -GNinja
+cmake --build build
+mv build/host.* ../build
+
+cd ../cart
+cmake -B build -GNinja
+cmake --build build
+mv build/cart.* ../build

cart/CMakeLists.txt

@@ -0,0 +1,39 @@
+# build for carts
+
+cmake_minimum_required (VERSION 3.18)
+
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}")
+
+set(CMAKE_SYSTEM_NAME WASI)
+set(CMAKE_SYSTEM_VERSION 1)
+set(CMAKE_SYSTEM_PROCESSOR wasm32)
+set(triple wasm32-wasi)
+
+# When building from source, WASI_SDK_PREFIX represents the generated directory
+if(NOT WASI_SDK_PREFIX)
+    set(WASI_SDK_PREFIX /opt/wasi-sdk)
+endif()
+
+set(CMAKE_C_COMPILER ${WASI_SDK_PREFIX}/bin/clang${WASI_HOST_EXE_SUFFIX})
+set(CMAKE_CXX_COMPILER ${WASI_SDK_PREFIX}/bin/clang++${WASI_HOST_EXE_SUFFIX})
+set(CMAKE_ASM_COMPILER ${WASI_SDK_PREFIX}/bin/clang${WASI_HOST_EXE_SUFFIX})
+set(CMAKE_AR ${WASI_SDK_PREFIX}/bin/llvm-ar${WASI_HOST_EXE_SUFFIX})
+set(CMAKE_RANLIB ${WASI_SDK_PREFIX}/bin/llvm-ranlib${WASI_HOST_EXE_SUFFIX})
+set(CMAKE_C_COMPILER_TARGET ${triple})
+set(CMAKE_CXX_COMPILER_TARGET ${triple})
+set(CMAKE_ASM_COMPILER_TARGET ${triple})
+
+# use only sysroot
+set(HAVE_FLAG_SEARCH_PATHS_FIRST 0)
+set(CMAKE_C_LINK_FLAGS "")
+set(CMAKE_CXX_LINK_FLAGS "")
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
+
+include_directories(${CMAKE_CURRENT_SOURCE_DIR})
+set(CMAKE_EXECUTABLE_SUFFIX ".wasm")
+
+add_executable(cart cart.c)
+target_link_options(cart PRIVATE -Wl,--initial-memory=128057344 -Wl,--import-memory)

cart/cart.c

@@ -0,0 +1,9 @@
+#define WASM_IMPORT(n) __attribute__((import_module("env"), import_name(n)))
+
+WASM_IMPORT("logtest")
+void logtest(char* message);
+
+int main(int argc, char* argv[]) {
+  logtest("I am inside the cart!");
+  return 0;
+}

host/CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.18)
+
+project(wasm_shared-host
+  DESCRIPTION "null0 engine experiment: shared memory"
+  HOMEPAGE_URL "https://github.com/notnullgames/wasm-shared"
+  VERSION 0.0.1
+  LANGUAGES C
+)
+
+if(NOT EMSCRIPTEN)
+  message(FATAL_ERROR "You must compile with emscripten.")
+endif()
+
+set(CMAKE_EXECUTABLE_SUFFIX ".mjs")
+
+add_executable(host host.c)
+target_link_options(host PRIVATE -sINITIAL_MEMORY=128MB  -sEXPORTED_FUNCTIONS=_logtest -sEXPORTED_RUNTIME_METHODS=wasmMemory)

test.htm

@@ -7,12 +7,19 @@
 </body>
 
 <script type="module">
-import loadHost from './build/wasm_shared-host.mjs'
+import loadHost from './build/host.mjs'
 
 
 // this will take an emscripten host, and setup imports for plain-wasm cart
 function getImports(host) {
   const out = {
+    wasi_snapshot_preview1: {
+      args_get(){},
+      args_sizes_get() {
+        return 0
+      },
+      proc_exit(){}
+    },
     env: {
       memory: host.wasmMemory
     }
@@ -27,9 +34,9 @@
 }
 
 
-const cart = (await WebAssembly.instantiateStreaming(fetch("./build/wasm_shared-cart.wasm"), getImports(await loadHost()))).instance.exports
+const cart = (await WebAssembly.instantiateStreaming(fetch("./build/cart.wasm"), getImports(await loadHost()))).instance.exports
 
 // call cart's test, which will call host's logtest
-cart.test()
+cart._start()
 
 </script>