serializer_macros.c

#include <stdio.h>
#include <string.h>

// serializing macros
#define serialize1(name, t1) void name(char* buffer, t1 a) { \
  memcpy(buffer, &a, sizeof(t1)); }
#define serialize2(name, t1,t2) void name(char* buffer, t1 a, t2 b) { \
  memcpy(buffer, &a, sizeof(t1)); \
  memcpy(buffer + sizeof(t1), &b, sizeof(t1)); }

serialize1(foo, int);        // define serializer foo(int)
serialize2(bar, char, int);  // define serializer bar(char, int)

int main(void) {
  char buffer[255] = {0};  // serialize bytes into this buffer

  foo(buffer, 97);  // serialize (int) 97 into buffer
  bar(buffer + sizeof(int), 'b', 99);  // serialize (char)'b' and (int)99 into buffer

  // print buffer (in hex) to check it
  int length = sizeof(int) + sizeof(char) + sizeof(int);
  for (int i=0; i<length; i++) printf("%p ", buffer[i]);
  printf("\n");

  // output:
  // 0x61 0x0 0x0 0x0 0x62 0x63 0x0 0x0 0x0

  return 0;
}