add simple sum example

examples/embed/host.c

@@ -0,0 +1,75 @@
+// https://github.com/bytecodealliance/wasm-micro-runtime/blob/WAMR-2.4.4/doc/embed_wamr.md
+
+// #include <stdio.h>
+#include <string.h>
+
+#include "lib.c"
+
+// #include "bh_read_file.h"
+#include "bh_platform.h"
+#include "wasm_export.h"
+
+#include "__WASM_ARRAY_FILE__"
+
+#define STACK_SIZE (8 * 1024)
+#define HEAP_SIZE (8 * 1024)
+
+// TODO: Set this up so the lsp actually finds the includes...
+
+MAIN() {
+  char error_buf[128];
+  wasm_module_t module;
+  wasm_module_inst_t module_inst;
+  wasm_function_inst_t func;
+  wasm_exec_env_t exec_env;
+  uint32 stack_size = 8 * 1024;
+  uint32 heap_size = 8 * 1024;
+
+  /* initialize the wasm runtime */
+  RuntimeInitArgs init_args;
+  memset(&init_args, 0, sizeof(init_args));
+
+  init_args.mem_alloc_type = Alloc_With_System_Allocator;
+  if (!wasm_runtime_full_init(&init_args)) {
+    return;
+  }
+
+  /* parse the WASM file from buffer and create a WASM module */
+  module = wasm_runtime_load(__WASM_ARRAY__, __WASM_ARRAY_LEN__, error_buf,
+                             sizeof(error_buf));
+
+  /* create an instance of the WASM module (WASM linear memory is ready) */
+  module_inst = wasm_runtime_instantiate(module, stack_size, heap_size,
+                                         error_buf, sizeof(error_buf));
+
+  /* lookup a WASM function by its name, the function signature can NULL here */
+  func = wasm_runtime_lookup_function(module_inst, "wasm_module");
+
+  /* create an execution environment to execute arbitrary WASM functions */
+  exec_env = wasm_runtime_create_exec_env(module_inst, stack_size);
+
+  /* arguments are always transferred in 32-bit element */
+  uint32 args[1];
+
+  /* call an arbitrary WASM function */
+  MARKER(start_trace);
+  if (!wasm_runtime_call_wasm(exec_env, func, 0, args)) {
+    /* function wasn't called correctly */
+    POSIX_PRINTF("Failed to call function 'wasm_module'!\n");
+  }
+  MARKER(stop_trace);
+
+  POSIX_PRINTF("Sum: %d\n!", args[0]);
+
+  /* the return value is stored in args[0] */
+  if (args[0] == 100) {
+    MARKER(ok_marker);
+  } else {
+    MARKER(fail_marker);
+  }
+
+  wasm_runtime_destroy_exec_env(exec_env);
+  wasm_runtime_deinstantiate(module_inst);
+  wasm_runtime_unload(module);
+  wasm_runtime_destroy();
+}