list_readers.c

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/*
 * This file is part of the Fun programming language.
 * https://fun-lang.xyz/
 *
 * Copyright 2025 Johannes Findeisen <you@hanez.org>
 * Licensed under the terms of the Apache-2.0 license.
 * https://opensource.org/license/apache-2-0
 */



/* PCSC list_readers */
case OP_PCSC_LIST_READERS: {
#ifdef FUN_WITH_PCSC
 /* Pop context id; return [] if anything goes wrong */
 Value vid = pop_value(vm);
 int id = (int)vid.i;
 free_value(vid);

 pcsc_ctx_entry *e = pcsc_get_ctx(id);
 if (!e) {
 push_value(vm, make_array_from_values(NULL, 0));
 break;
 }

 DWORD sz = 0;
 LONG rv = SCardListReaders(e->ctx, NULL, NULL, &sz);
 if (rv != SCARD_S_SUCCESS || sz == 0) {
 push_value(vm, make_array_from_values(NULL, 0));
 break;
 }

 char *msz = (char *)malloc(sz);
 if (!msz) {
 push_value(vm, make_array_from_values(NULL, 0));
 break;
 }

 rv = SCardListReaders(e->ctx, NULL, msz, &sz);
 if (rv != SCARD_S_SUCCESS) {
 free(msz);
 push_value(vm, make_array_from_values(NULL, 0));
 break;
 }

 Value vals[64];
 int count = 0;
 char *p = msz;
 while (*p && count < (int)(sizeof(vals) / sizeof(vals[0]))) {
 size_t n = strlen(p);
 vals[count++] = make_string(p);
 p += n + 1;
 }
 Value arr = make_array_from_values(vals, count);
 for (int i = 0; i < count; ++i)
 free_value(vals[i]);
 free(msz);

 if (arr.type != VAL_ARRAY) {
 push_value(vm, make_array_from_values(NULL, 0));
 } else {
 push_value(vm, arr);
 }
#else
 /* Fallback (no PCSC): consume ctx id and return [] to keep the stack consistent */
 Value vid = pop_value(vm);
 free_value(vid);
 push_value(vm, make_array_from_values(NULL, 0));
#endif
 break;
}