#include #include "../wasmer.h" #include #include #include static bool print_str_called = false; static int memory_len = 0; static int ptr_len = 0; static char actual_str[14] = {}; void print_str(wasmer_instance_context_t *ctx, int32_t ptr, int32_t len) { const wasmer_memory_t *memory = wasmer_instance_context_memory(ctx, 0); uint32_t mem_len = wasmer_memory_length(memory); uint8_t *mem_bytes = wasmer_memory_data(memory); for (int32_t idx = 0; idx < len; idx++) { actual_str[idx] = mem_bytes[ptr + idx]; } actual_str[13] = '\0'; printf("In print_str, memory len: %d, ptr_len: %d\n, str %s", mem_len, len, actual_str); print_str_called = true; memory_len = mem_len; ptr_len = len; } int main() { wasmer_value_tag params_sig[] = {WASM_I32, WASM_I32}; wasmer_value_tag returns_sig[] = {}; printf("Creating new func\n"); wasmer_import_func_t *func = wasmer_import_func_new((void (*)(void *)) print_str, params_sig, 2, returns_sig, 0); wasmer_import_t import; char *module_name = "env"; wasmer_byte_array module_name_bytes; module_name_bytes.bytes = (const uint8_t *) module_name; module_name_bytes.bytes_len = strlen(module_name); char *import_name = "print_str"; wasmer_byte_array import_name_bytes; import_name_bytes.bytes = (const uint8_t *) import_name; import_name_bytes.bytes_len = strlen(import_name); import.module_name = module_name_bytes; import.import_name = import_name_bytes; import.tag = WASM_FUNCTION; import.value.func = func; wasmer_import_t imports[] = {import}; // Read the wasm file bytes FILE *file = fopen("wasm_sample_app.wasm", "r"); fseek(file, 0, SEEK_END); long len = ftell(file); uint8_t *bytes = malloc(len); fseek(file, 0, SEEK_SET); fread(bytes, 1, len, file); fclose(file); printf("Instantiating\n"); wasmer_instance_t *instance = NULL; wasmer_result_t compile_result = wasmer_instantiate(&instance, bytes, len, imports, 1); printf("Compile result: %d\n", compile_result); assert(compile_result == WASMER_OK); wasmer_value_t params[] = {}; wasmer_value_t results[] = {}; wasmer_result_t call_result = wasmer_instance_call(instance, "hello_wasm", params, 0, results, 0); printf("Call result: %d\n", call_result); int error_len = wasmer_last_error_length(); printf("Error len: `%d`\n", error_len); char *error_str = malloc(error_len); wasmer_last_error_message(error_str, error_len); printf("Error str: `%s`\n", error_str); assert(call_result == WASMER_OK); assert(print_str_called); assert(memory_len == 17); assert(ptr_len == 13); assert(0 == strcmp(actual_str, "Hello, World!")); printf("Destroying func\n"); wasmer_import_func_destroy(func); printf("Destroy instance\n"); wasmer_instance_destroy(instance); return 0; }