1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <inttypes.h>
5
6 #include "wasm.h"
7
8 #define own
9
10 // A function to be called from Wasm code.
fail_callback(void * env,const wasm_val_t args[],wasm_val_t results[])11 own wasm_trap_t* fail_callback(
12 void* env, const wasm_val_t args[], wasm_val_t results[]
13 ) {
14 printf("Calling back...\n");
15 own wasm_name_t message;
16 wasm_name_new_from_string(&message, "callback abort");
17 own wasm_trap_t* trap = wasm_trap_new((wasm_store_t*)env, &message);
18 wasm_name_delete(&message);
19 return trap;
20 }
21
22
print_frame(wasm_frame_t * frame)23 void print_frame(wasm_frame_t* frame) {
24 printf("> %p @ 0x%zx = %"PRIu32".0x%zx\n",
25 wasm_frame_instance(frame),
26 wasm_frame_module_offset(frame),
27 wasm_frame_func_index(frame),
28 wasm_frame_func_offset(frame)
29 );
30 }
31
32
main(int argc,const char * argv[])33 int main(int argc, const char* argv[]) {
34 // Initialize.
35 printf("Initializing...\n");
36 wasm_engine_t* engine = wasm_engine_new();
37 wasm_store_t* store = wasm_store_new(engine);
38
39 // Load binary.
40 printf("Loading binary...\n");
41 FILE* file = fopen("trap.wasm", "r");
42 if (!file) {
43 printf("> Error loading module!\n");
44 return 1;
45 }
46 fseek(file, 0L, SEEK_END);
47 size_t file_size = ftell(file);
48 fseek(file, 0L, SEEK_SET);
49 wasm_byte_vec_t binary;
50 wasm_byte_vec_new_uninitialized(&binary, file_size);
51 if (fread(binary.data, file_size, 1, file) != 1) {
52 printf("> Error loading module!\n");
53 return 1;
54 }
55 fclose(file);
56
57 // Compile.
58 printf("Compiling module...\n");
59 own wasm_module_t* module = wasm_module_new(store, &binary);
60 if (!module) {
61 printf("> Error compiling module!\n");
62 return 1;
63 }
64
65 wasm_byte_vec_delete(&binary);
66
67 // Create external print functions.
68 printf("Creating callback...\n");
69 own wasm_functype_t* fail_type =
70 wasm_functype_new_0_1(wasm_valtype_new_i32());
71 own wasm_func_t* fail_func =
72 wasm_func_new_with_env(store, fail_type, fail_callback, store, NULL);
73
74 wasm_functype_delete(fail_type);
75
76 // Instantiate.
77 printf("Instantiating module...\n");
78 const wasm_extern_t* imports[] = { wasm_func_as_extern(fail_func) };
79 own wasm_instance_t* instance =
80 wasm_instance_new(store, module, imports, NULL);
81 if (!instance) {
82 printf("> Error instantiating module!\n");
83 return 1;
84 }
85
86 wasm_func_delete(fail_func);
87
88 // Extract export.
89 printf("Extracting exports...\n");
90 own wasm_extern_vec_t exports;
91 wasm_instance_exports(instance, &exports);
92 if (exports.size < 2) {
93 printf("> Error accessing exports!\n");
94 return 1;
95 }
96
97 wasm_module_delete(module);
98 wasm_instance_delete(instance);
99
100 // Call.
101 for (int i = 0; i < 2; ++i) {
102 const wasm_func_t* func = wasm_extern_as_func(exports.data[i]);
103 if (func == NULL) {
104 printf("> Error accessing export!\n");
105 return 1;
106 }
107
108 printf("Calling export %d...\n", i);
109 own wasm_trap_t* trap = wasm_func_call(func, NULL, NULL);
110 if (!trap) {
111 printf("> Error calling function, expected trap!\n");
112 return 1;
113 }
114
115 printf("Printing message...\n");
116 own wasm_name_t message;
117 wasm_trap_message(trap, &message);
118 printf("> %s\n", message.data);
119
120 printf("Printing origin...\n");
121 own wasm_frame_t* frame = wasm_trap_origin(trap);
122 if (frame) {
123 print_frame(frame);
124 wasm_frame_delete(frame);
125 } else {
126 printf("> Empty origin.\n");
127 }
128
129 printf("Printing trace...\n");
130 own wasm_frame_vec_t trace;
131 wasm_trap_trace(trap, &trace);
132 if (trace.size > 0) {
133 for (size_t i = 0; i < trace.size; ++i) {
134 print_frame(trace.data[i]);
135 }
136 } else {
137 printf("> Empty trace.\n");
138 }
139
140 wasm_frame_vec_delete(&trace);
141 wasm_trap_delete(trap);
142 wasm_name_delete(&message);
143 }
144
145 wasm_extern_vec_delete(&exports);
146
147 // Shut down.
148 printf("Shutting down...\n");
149 wasm_store_delete(store);
150 wasm_engine_delete(engine);
151
152 // All done.
153 printf("Done.\n");
154 return 0;
155 }
156