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// Win32 Compatibility Code added by Yulian Kalev and Stefan Georg Weber.
#include <stdio.h>
#include <stdint.h> // for intptr_t
#include <stdlib.h>
#include <windows.h>
#include <wincrypt.h>
#include <gmp.h>
#include "pbc_random.h"
#include "pbc_utils.h"
#include "pbc_memory.h"
static void win32_mpz_random(mpz_t r, mpz_t limit, void *data) {
UNUSED_VAR (data);
HCRYPTPROV phProv;
unsigned int error;
if (!CryptAcquireContext(&phProv,NULL,NULL,PROV_RSA_FULL,0)) {
error = GetLastError();
if (error == 0x80090016) { //need to create a new keyset
if (!CryptAcquireContext(&phProv,NULL,NULL,PROV_RSA_FULL,CRYPT_NEWKEYSET)) {
pbc_error("Couldn't create CryptContext: %x", (int)GetLastError());
return;
}
} else {
pbc_error("Couldn't create CryptContext: %x", error);
return;
}
}
int n, bytecount, leftover;
unsigned char *bytes;
mpz_t z;
mpz_init(z);
n = mpz_sizeinbase(limit, 2);
bytecount = (n + 7) / 8;
leftover = n % 8;
bytes = (unsigned char *) pbc_malloc(bytecount);
for (;;) {
CryptGenRandom(phProv,bytecount,(byte *)bytes);
if (leftover) {
*bytes = *bytes % (1 << leftover);
}
mpz_import(z, bytecount, 1, 1, 0, 0, bytes);
if (mpz_cmp(z, limit) < 0) break;
}
CryptReleaseContext(phProv,0);
mpz_set(r, z);
mpz_clear(z);
pbc_free(bytes);
}
void pbc_init_random(void) {
pbc_random_set_function(win32_mpz_random, NULL);
}
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