You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
121 lines
3.7 KiB
121 lines
3.7 KiB
/*
|
|
Example of instantiating a WebAssembly which uses WASI imports.
|
|
|
|
You can compile and run this example on Linux with:
|
|
|
|
cargo build --release -p wasmtime-c-api
|
|
cc examples/wasi/main.c \
|
|
-I crates/c-api/include \
|
|
-I crates/c-api/wasm-c-api/include \
|
|
target/release/libwasmtime.a \
|
|
-lpthread -ldl -lm \
|
|
-o wasi
|
|
./wasi
|
|
|
|
Note that on Windows and macOS the command will be similar, but you'll need
|
|
to tweak the `-lpthread` and such annotations.
|
|
*/
|
|
|
|
#include <assert.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <wasm.h>
|
|
#include <wasi.h>
|
|
#include <wasmtime.h>
|
|
|
|
#define MIN(a, b) ((a) < (b) ? (a) : (b))
|
|
|
|
static void exit_with_error(const char *message, wasmtime_error_t *error, wasm_trap_t *trap);
|
|
|
|
int main() {
|
|
int ret = 0;
|
|
// Set up our context
|
|
wasm_engine_t *engine = wasm_engine_new();
|
|
assert(engine != NULL);
|
|
wasm_store_t *store = wasm_store_new(engine);
|
|
assert(store != NULL);
|
|
|
|
wasm_byte_vec_t wasm;
|
|
// Load our input file to parse it next
|
|
FILE* file = fopen("target/wasm32-wasi/debug/wasi.wasm", "rb");
|
|
if (!file) {
|
|
printf("> Error loading file!\n");
|
|
exit(1);
|
|
}
|
|
fseek(file, 0L, SEEK_END);
|
|
size_t file_size = ftell(file);
|
|
wasm_byte_vec_new_uninitialized(&wasm, file_size);
|
|
fseek(file, 0L, SEEK_SET);
|
|
if (fread(wasm.data, file_size, 1, file) != 1) {
|
|
printf("> Error loading module!\n");
|
|
exit(1);
|
|
}
|
|
fclose(file);
|
|
|
|
// Compile our modules
|
|
wasm_module_t *module = NULL;
|
|
wasmtime_error_t *error = wasmtime_module_new(engine, &wasm, &module);
|
|
if (!module)
|
|
exit_with_error("failed to compile module", error, NULL);
|
|
wasm_byte_vec_delete(&wasm);
|
|
|
|
// Instantiate wasi
|
|
wasi_config_t *wasi_config = wasi_config_new();
|
|
assert(wasi_config);
|
|
wasi_config_inherit_argv(wasi_config);
|
|
wasi_config_inherit_env(wasi_config);
|
|
wasi_config_inherit_stdin(wasi_config);
|
|
wasi_config_inherit_stdout(wasi_config);
|
|
wasi_config_inherit_stderr(wasi_config);
|
|
wasm_trap_t *trap = NULL;
|
|
wasi_instance_t *wasi = wasi_instance_new(store, "wasi_snapshot_preview1", wasi_config, &trap);
|
|
if (wasi == NULL)
|
|
exit_with_error("failed to instantiate WASI", NULL, trap);
|
|
|
|
wasmtime_linker_t *linker = wasmtime_linker_new(store);
|
|
error = wasmtime_linker_define_wasi(linker, wasi);
|
|
if (error != NULL)
|
|
exit_with_error("failed to link wasi", error, NULL);
|
|
|
|
// Instantiate the module
|
|
wasm_name_t empty;
|
|
wasm_name_new_from_string(&empty, "");
|
|
wasm_instance_t *instance = NULL;
|
|
error = wasmtime_linker_module(linker, &empty, module);
|
|
if (error != NULL)
|
|
exit_with_error("failed to instantiate module", error, NULL);
|
|
|
|
// Run it.
|
|
wasm_func_t* func;
|
|
wasmtime_linker_get_default(linker, &empty, &func);
|
|
if (error != NULL)
|
|
exit_with_error("failed to locate default export for module", error, NULL);
|
|
|
|
wasm_val_vec_t args_vec = WASM_EMPTY_VEC;
|
|
wasm_val_vec_t results_vec = WASM_EMPTY_VEC;
|
|
error = wasmtime_func_call(func, &args_vec, &results_vec, &trap);
|
|
if (error != NULL)
|
|
exit_with_error("error calling default export", error, trap);
|
|
|
|
// Clean up after ourselves at this point
|
|
wasm_name_delete(&empty);
|
|
wasm_module_delete(module);
|
|
wasm_store_delete(store);
|
|
wasm_engine_delete(engine);
|
|
return 0;
|
|
}
|
|
|
|
static void exit_with_error(const char *message, wasmtime_error_t *error, wasm_trap_t *trap) {
|
|
fprintf(stderr, "error: %s\n", message);
|
|
wasm_byte_vec_t error_message;
|
|
if (error != NULL) {
|
|
wasmtime_error_message(error, &error_message);
|
|
wasmtime_error_delete(error);
|
|
} else {
|
|
wasm_trap_message(trap, &error_message);
|
|
wasm_trap_delete(trap);
|
|
}
|
|
fprintf(stderr, "%.*s\n", (int) error_message.size, error_message.data);
|
|
wasm_byte_vec_delete(&error_message);
|
|
exit(1);
|
|
}
|
|
|