static int ffi_type_check(ktap_state_t *ks, csymbol_func *csf, int idx)
{
StkId arg;
csymbol *cs;
if (idx >= csymf_arg_nr(csf))
return 0;
arg = kp_arg(ks, idx + 1);
cs = csymf_arg(ks, csf, idx);
if (!kp_cdata_type_match(ks, cs, arg))
return 0;
else {
kp_error(ks, "Cannot convert to csymbol %s for arg %d\n",
csym_name(cs), idx);
return -1;
}
}
void __cp_symbol_dump_func(csymbol *cs)
{
int i;
csymbol *ncs;
csymbol_func *fcs = csym_func(cs);
printf("=== [%s] function definition =============\n", csym_name(cs));
ncs = cp_csymf_ret(fcs);
printf("address: %p\n", fcs->addr);
printf("return type: \n");
printf("\tcsym_id: %d, ffi_ctype: %d, %s\n",
fcs->ret_id, ncs->type, csym_name(ncs));
printf("args type (%d): \n", fcs->arg_nr);
for (i = 0; i < csymf_arg_nr(fcs); i++) {
printf("\t (%d) ", i);
printf("csym_id: %d, ", fcs->arg_ids[i]);
ncs = cp_csymf_arg(fcs, i);
printf("ffi_ctype: %d, %s\n", ncs->type, csym_name(ncs));
}
}
/*
* Call C into function
* First argument should be function symbol address, argument types
* and return type.
* Left arguments should be arguments for calling the C function.
* Types between Ktap and C are converted automatically.
* Only support x86_64 function call by now
*/
int ffi_call(ktap_state_t *ks, csymbol_func *csf)
{
int i;
int expected_arg_nr, arg_nr;
ktap_closure_t *cl;
void *rvalue;
expected_arg_nr = csymf_arg_nr(csf);
arg_nr = kp_arg_nr(ks);
/* check stack status for C call */
if (!csf->has_var_arg && expected_arg_nr != arg_nr) {
kp_error(ks, "wrong argument number %d, which should be %d\n",
arg_nr, expected_arg_nr);
goto out;
}
if (csf->has_var_arg && expected_arg_nr > arg_nr) {
kp_error(ks, "argument number %d, which should be bigger than %d\n",
arg_nr, expected_arg_nr);
goto out;
}
/* maybe useful later, leave it here first */
cl = clvalue(kp_arg(ks, arg_nr + 1));
/* check the argument types */
for (i = 0; i < arg_nr; i++) {
if (ffi_type_check(ks, csf, i) < 0)
goto out;
}
/* platform-specific calling workflow */
ffi_call_arch(ks, csf, &rvalue);
kp_verbose_printf(ks, "Finish FFI call\n");
out:
return ffi_set_return(ks, rvalue, csymf_ret_id(csf));
}
static csymbol *ffi_get_arg_csym(ktap_state_t *ks, csymbol_func *csf, int idx)
{
StkId arg;
csymbol *cs;
if (idx < csymf_arg_nr(csf))
return csymf_arg(ks, csf, idx);
arg = kp_arg(ks, idx + 1);
cs = id_to_csym(ks, ffi_get_csym_id(ks, "void *"));
switch (ttypenv(arg)) {
case KTAP_TYPE_LIGHTUSERDATA:
case KTAP_TYPE_BOOLEAN:
case KTAP_TYPE_NUMBER:
case KTAP_TYPE_STRING:
return cs;
case KTAP_TYPE_CDATA:
return cd_csym(ks, cdvalue(arg));
default:
kp_error(ks, "Error: Cannot get type for arg %d\n", idx);
return cs;
}
}
