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Brandon Fish bjfish

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View wasmer-c-api-8.c
// Call the exported "hello_wasm" function of our instance
wasmer_value_t params[] = {};
wasmer_value_t result_one;
wasmer_value_t results[] = {result_one};
wasmer_result_t call_result = wasmer_instance_call(instance, "_hello_wasm", params, 0, results, 1);
printf("Call result: %d\n", call_result);
assert(call_result == WASMER_OK);
assert(print_str_called);
// Use *_destroy methods to cleanup as specified in the header documentation
View wasmer-c-api-7.c
// Call the exported "hello_wasm" function of our instance
wasmer_value_t params[] = {};
wasmer_value_t result_one;
wasmer_value_t results[] = {result_one};
wasmer_result_t call_result = wasmer_instance_call(instance, "_hello_wasm", params, 0, results, 1);
printf("Call result: %d\n", call_result);
assert(call_result == WASMER_OK);
assert(print_str_called);
// Use *_destroy methods to cleanup as specified in the header documentation
View wasmer-c-api-6.c
// Read the wasm file bytes
FILE *file = fopen("wasm-sample-app/target.wasm", "r");
fseek(file, 0, SEEK_END);
long len = ftell(file);
uint8_t *bytes = malloc(len);
fseek(file, 0, SEEK_SET);
fread(bytes, 1, len, file);
fclose(file);
// Creates a WebAssembly Instance from wasm bytes and imports
View wasmer-c-api-5.c
// Create module name for our imports
// represented in bytes for UTF-8 compatability
char *module_name = "env";
wasmer_byte_array module_name_bytes;
module_name_bytes.bytes = module_name;
module_name_bytes.bytes_len = strlen(module_name);
// Define a function import
char *import_name = "_print_str";
wasmer_byte_array import_name_bytes;
View wasmer-c-api-4.c
int main()
{
wasmer_value_tag params_sig[] = {WASM_I32, WASM_I32};
wasmer_value_tag returns_sig[] = {};
wasmer_import_func_t *func = wasmer_import_func_new(print_str, params_sig, 2, returns_sig, 0);
View wasmer-c-api-3.c
void print_wasmer_error()
{
int error_len = wasmer_last_error_length();
printf("Error len: `%d`\n", error_len);
char *error_str = malloc(error_len);
wasmer_last_error_message(error_str, error_len);
printf("Error str: `%s`\n", error_str);
}
View wasmer-c-api-2.c
void print_str(wasmer_instance_context_t *ctx, int32_t ptr, int32_t len)
{
print_str_called = true;
wasmer_memory_t *memory = wasmer_instance_context_memory(ctx, 0);
uint32_t mem_len = wasmer_memory_length(memory);
uint8_t *mem_bytes = wasmer_memory_data(memory);
printf("%.*s", len, mem_bytes + ptr);
}
@bjfish
bjfish / source.c
Created Mar 3, 2019
Hello World C Wasm Example App
View source.c
extern void print_str(char *ptr, int len);
int hello_wasm()
{
char *str = "Hello, World!";
print_str(str, 13);
return 0;
}
@bjfish
bjfish / wasmer-c-api-example.c
Last active Mar 3, 2019
Wasmer C API Example
View wasmer-c-api-example.c
#include <stdio.h>
#include "rust-build/src/wasmer-runtime-c-api/lib/runtime-c-api/wasmer.h"
#include <assert.h>
#include <stdint.h>
static print_str_called = false;
// Host function that will be imported into the Web Assembly Instance
void print_str(wasmer_instance_context_t *ctx, int32_t ptr, int32_t len)
{
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