xref: /wasmtime-44.0.1/examples/fib-debug/main.c (revision 331b0dee)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <inttypes.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, wasm_trap_t *trap);
11 
12 int main(int argc, const char* argv[]) {
13   // Configuring engine to support generating of DWARF info.
14   // lldb can be used to attach to the program and observe
15   // original fib-wasm.c source code and variables.
16   wasm_config_t* config = wasm_config_new();
17   wasmtime_config_debug_info_set(config, true);
18 
19   // Initialize.
20   printf("Initializing...\n");
21   wasm_engine_t* engine = wasm_engine_new_with_config(config);
22   wasmtime_store_t* store = wasmtime_store_new(engine, NULL, NULL);
23   wasmtime_context_t* context = wasmtime_store_context(store);
24 
25   // Load binary.
26   printf("Loading binary...\n");
27   FILE* file = fopen("target/wasm32-unknown-unknown/debug/fib.wasm", "rb");
28   if (!file) {
29     printf("> Error opening module!\n");
30     return 1;
31   }
32   fseek(file, 0L, SEEK_END);
33   size_t file_size = ftell(file);
34   fseek(file, 0L, SEEK_SET);
35   wasm_byte_vec_t binary;
36   wasm_byte_vec_new_uninitialized(&binary, file_size);
37   if (fread(binary.data, file_size, 1, file) != 1) {
38     printf("> Error reading module!\n");
39     return 1;
40   }
41   fclose(file);
42 
43   // Compile.
44   printf("Compiling module...\n");
45   wasmtime_module_t *module = NULL;
46   wasmtime_error_t* error = wasmtime_module_new(engine, (uint8_t*) binary.data, binary.size, &module);
47   if (!module)
48     exit_with_error("failed to compile module", error, NULL);
49   wasm_byte_vec_delete(&binary);
50 
51   // Instantiate.
52   printf("Instantiating module...\n");
53   wasmtime_instance_t instance;
54   wasm_trap_t *trap = NULL;
55   error = wasmtime_instance_new(context, module, NULL, 0, &instance, &trap);
56   if (error != NULL || trap != NULL)
57     exit_with_error("failed to instantiate", error, trap);
58   wasmtime_module_delete(module);
59 
60   // Extract export.
61   wasmtime_extern_t fib;
62   bool ok = wasmtime_instance_export_get(context, &instance, "fib", 3, &fib);
63   assert(ok);
64 
65   // Call.
66   printf("Calling fib...\n");
67   wasmtime_val_t params[1];
68   params[0].kind = WASMTIME_I32;
69   params[0].of.i32 = 6;
70   wasmtime_val_t results[1];
71   error = wasmtime_func_call(context, &fib.of.func, params, 1, results, 1, &trap);
72   if (error != NULL || trap != NULL)
73     exit_with_error("failed to call function", error, trap);
74 
75   assert(results[0].kind == WASMTIME_I32);
76   printf("> fib(6) = %d\n", results[0].of.i32);
77 
78   // Shut down.
79   printf("Shutting down...\n");
80   wasmtime_store_delete(store);
81   wasm_engine_delete(engine);
82 
83   // All done.
84   printf("Done.\n");
85   return 0;
86 }
87 
88 static void exit_with_error(const char *message, wasmtime_error_t *error, wasm_trap_t *trap) {
89   fprintf(stderr, "error: %s\n", message);
90   wasm_byte_vec_t error_message;
91   if (error != NULL) {
92     wasmtime_error_message(error, &error_message);
93   } else {
94     wasm_trap_message(trap, &error_message);
95   }
96   fprintf(stderr, "%.*s\n", (int) error_message.size, error_message.data);
97   wasm_byte_vec_delete(&error_message);
98   exit(1);
99 }
100