1 #include <inttypes.h> 2 #include <stdio.h> 3 #include <stdlib.h> 4 #include <string.h> 5 #include <wasm.h> 6 #include <wasmtime.h> 7 8 #define own 9 10 static void exit_with_error(const char *message, wasmtime_error_t *error, 11 wasm_trap_t *trap); 12 13 int main(int argc, const char *argv[]) { 14 // Configuring engine to support generating of DWARF info. 15 // lldb can be used to attach to the program and observe 16 // original fib-wasm.c source code and variables. 17 wasm_config_t *config = wasm_config_new(); 18 wasmtime_config_debug_info_set(config, true); 19 20 // Initialize. 21 printf("Initializing...\n"); 22 wasm_engine_t *engine = wasm_engine_new_with_config(config); 23 wasmtime_store_t *store = wasmtime_store_new(engine, NULL, NULL); 24 wasmtime_context_t *context = wasmtime_store_context(store); 25 26 // Load binary. 27 printf("Loading binary...\n"); 28 FILE *file = fopen("target/wasm32-unknown-unknown/debug/fib.wasm", "rb"); 29 if (!file) { 30 printf("> Error opening module!\n"); 31 return 1; 32 } 33 fseek(file, 0L, SEEK_END); 34 size_t file_size = ftell(file); 35 fseek(file, 0L, SEEK_SET); 36 wasm_byte_vec_t binary; 37 wasm_byte_vec_new_uninitialized(&binary, file_size); 38 if (fread(binary.data, file_size, 1, file) != 1) { 39 printf("> Error reading module!\n"); 40 return 1; 41 } 42 fclose(file); 43 44 // Compile. 45 printf("Compiling module...\n"); 46 wasmtime_module_t *module = NULL; 47 wasmtime_error_t *error = 48 wasmtime_module_new(engine, (uint8_t *)binary.data, binary.size, &module); 49 if (!module) 50 exit_with_error("failed to compile module", error, NULL); 51 wasm_byte_vec_delete(&binary); 52 53 // Instantiate. 54 printf("Instantiating module...\n"); 55 wasmtime_instance_t instance; 56 wasm_trap_t *trap = NULL; 57 error = wasmtime_instance_new(context, module, NULL, 0, &instance, &trap); 58 if (error != NULL || trap != NULL) 59 exit_with_error("failed to instantiate", error, trap); 60 wasmtime_module_delete(module); 61 62 // Extract export. 63 wasmtime_extern_t fib; 64 bool ok = wasmtime_instance_export_get(context, &instance, "fib", 3, &fib); 65 assert(ok); 66 67 // Call. 68 printf("Calling fib...\n"); 69 wasmtime_val_t params[1]; 70 params[0].kind = WASMTIME_I32; 71 params[0].of.i32 = 6; 72 wasmtime_val_t results[1]; 73 error = 74 wasmtime_func_call(context, &fib.of.func, params, 1, results, 1, &trap); 75 if (error != NULL || trap != NULL) 76 exit_with_error("failed to call function", error, trap); 77 78 assert(results[0].kind == WASMTIME_I32); 79 printf("> fib(6) = %d\n", results[0].of.i32); 80 81 // Shut down. 82 printf("Shutting down...\n"); 83 wasmtime_store_delete(store); 84 wasm_engine_delete(engine); 85 86 // All done. 87 printf("Done.\n"); 88 return 0; 89 } 90 91 static void exit_with_error(const char *message, wasmtime_error_t *error, 92 wasm_trap_t *trap) { 93 fprintf(stderr, "error: %s\n", message); 94 wasm_byte_vec_t error_message; 95 if (error != NULL) { 96 wasmtime_error_message(error, &error_message); 97 } else { 98 wasm_trap_message(trap, &error_message); 99 } 100 fprintf(stderr, "%.*s\n", (int)error_message.size, error_message.data); 101 wasm_byte_vec_delete(&error_message); 102 exit(1); 103 } 104