xref: /wasmtime-44.0.1/examples/fib-debug/main.c (revision adff9d9d)
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 #ifdef WASMTIME_TEST_ONLY
9 // These are the declarations provided from GDB documentation, used to validate
10 // that we actually added some DWARF info:
11 // https://sourceware.org/gdb/current/onlinedocs/gdb.html/Declarations.html#Declarations
12 //
13 // NOTE: These are not required in your code, rather they are used for wasmtime
14 // testing only.
15 typedef enum {
16   JIT_NOACTION = 0,
17   JIT_REGISTER_FN,
18   JIT_UNREGISTER_FN
19 } jit_actions_t;
20 
21 struct jit_code_entry {
22   struct jit_code_entry *next_entry;
23   struct jit_code_entry *prev_entry;
24   const char *symfile_addr;
25   uint64_t symfile_size;
26 };
27 
28 struct jit_descriptor {
29   uint32_t version;
30   /* This type should be jit_actions_t, but we use uint32_t
31      to be explicit about the bitwidth.  */
32   uint32_t action_flag;
33   struct jit_code_entry *relevant_entry;
34   struct jit_code_entry *first_entry;
35 };
36 
37 /*
38  * Import the descriptor, defined elsewhere in wasmtime
39  */
40 extern struct jit_descriptor __jit_debug_descriptor;
41 #endif
42 
43 #define own
44 
45 static void exit_with_error(const char *message, wasmtime_error_t *error,
46                             wasm_trap_t *trap);
47 
main()48 int main() {
49   // Configuring engine to support generating of DWARF info.
50   // lldb can be used to attach to the program and observe
51   // original fib-wasm.c source code and variables.
52   wasm_config_t *config = wasm_config_new();
53   wasmtime_config_debug_info_set(config, true);
54   wasmtime_config_cranelift_opt_level_set(config, WASMTIME_OPT_LEVEL_NONE);
55 
56   // Initialize.
57   printf("Initializing...\n");
58   wasm_engine_t *engine = wasm_engine_new_with_config(config);
59   wasmtime_store_t *store = wasmtime_store_new(engine, NULL, NULL);
60   wasmtime_context_t *context = wasmtime_store_context(store);
61 
62 #ifdef WASMTIME_TEST_ONLY
63   // NOTE: This validation is for wasmtime testing and should not be included in
64   // your code.
65   if (__jit_debug_descriptor.first_entry != NULL) {
66     fprintf(stderr, "FAIL: JIT descriptor is already initialized\n");
67     return 1;
68   }
69 #endif
70 
71   // Load binary.
72   printf("Loading binary...\n");
73   FILE *file = fopen("target/wasm32-unknown-unknown/debug/fib.wasm", "rb");
74   if (!file) {
75     printf("> Error opening module!\n");
76     return 1;
77   }
78   fseek(file, 0L, SEEK_END);
79   size_t file_size = ftell(file);
80   fseek(file, 0L, SEEK_SET);
81   wasm_byte_vec_t binary;
82   wasm_byte_vec_new_uninitialized(&binary, file_size);
83   if (fread(binary.data, file_size, 1, file) != 1) {
84     printf("> Error reading module!\n");
85     return 1;
86   }
87   fclose(file);
88 
89   // Compile.
90   printf("Compiling module...\n");
91   wasmtime_module_t *module = NULL;
92   wasmtime_error_t *error =
93       wasmtime_module_new(engine, (uint8_t *)binary.data, binary.size, &module);
94   if (!module)
95     exit_with_error("failed to compile module", error, NULL);
96   wasm_byte_vec_delete(&binary);
97 
98   // Instantiate.
99   printf("Instantiating module...\n");
100   wasmtime_instance_t instance;
101   wasm_trap_t *trap = NULL;
102   error = wasmtime_instance_new(context, module, NULL, 0, &instance, &trap);
103   if (error != NULL || trap != NULL)
104     exit_with_error("failed to instantiate", error, trap);
105   wasmtime_module_delete(module);
106 
107 #ifdef WASMTIME_TEST_ONLY
108   // NOTE: This validation is for wasmtime testing and should not be included in
109   // your code.
110   if (__jit_debug_descriptor.first_entry == NULL) {
111     fprintf(stderr, "FAIL: JIT descriptor is NOT initialized\n");
112     return 1;
113   }
114 #endif
115 
116   // Extract export.
117   wasmtime_extern_t fib;
118   bool ok = wasmtime_instance_export_get(context, &instance, "fib", 3, &fib);
119   assert(ok);
120 
121   // Call.
122   printf("Calling fib...\n");
123   wasmtime_val_t params[1];
124   params[0].kind = WASMTIME_I32;
125   params[0].of.i32 = 6;
126   wasmtime_val_t results[1];
127   error =
128       wasmtime_func_call(context, &fib.of.func, params, 1, results, 1, &trap);
129   if (error != NULL || trap != NULL)
130     exit_with_error("failed to call function", error, trap);
131 
132   assert(results[0].kind == WASMTIME_I32);
133   printf("> fib(6) = %d\n", results[0].of.i32);
134 
135   // Shut down.
136   printf("Shutting down...\n");
137   wasmtime_store_delete(store);
138   wasm_engine_delete(engine);
139 
140   // All done.
141   printf("Done.\n");
142   return 0;
143 }
144 
exit_with_error(const char * message,wasmtime_error_t * error,wasm_trap_t * trap)145 static void exit_with_error(const char *message, wasmtime_error_t *error,
146                             wasm_trap_t *trap) {
147   fprintf(stderr, "error: %s\n", message);
148   wasm_byte_vec_t error_message;
149   if (error != NULL) {
150     wasmtime_error_message(error, &error_message);
151   } else {
152     wasm_trap_message(trap, &error_message);
153   }
154   fprintf(stderr, "%.*s\n", (int)error_message.size, error_message.data);
155   wasm_byte_vec_delete(&error_message);
156   exit(1);
157 }
158