#include "d0_bignum.h"
#include <gmp.h>
+#include <string.h>
struct d0_bignum_s
{
return bignum;
}
+ssize_t d0_bignum_export_unsigned(const d0_bignum_t *bignum, void *buf, size_t bufsize)
+{
+ size_t count;
+ count = (mpz_sizeinbase(bignum->z, 2) + 7) / 8;
+ if(count > bufsize)
+ return -1;
+ if(bufsize > count)
+ {
+ // pad from left (big endian numbers!)
+ memset(buf, 0, bufsize - count);
+ buf += bufsize - count;
+ }
+ bufsize = count;
+ mpz_export(buf, &bufsize, 1, 1, 0, 0, bignum->z);
+ if(bufsize > count)
+ {
+ // REALLY BAD
+ // mpz_sizeinbase lied to us
+ // buffer overflow
+ // there is no sane way whatsoever to handle this
+ abort();
+ }
+ if(bufsize < count)
+ {
+ // BAD
+ // mpz_sizeinbase lied to us
+ // move the number
+ if(bufsize == 0)
+ {
+ memset(buf, 0, count);
+ }
+ else
+ {
+ memmove(buf + count - bufsize, buf, bufsize);
+ memset(buf, 0, count - bufsize);
+ }
+ }
+ return bufsize;
+}
+
+d0_bignum_t *d0_bignum_import_unsigned(d0_bignum_t *bignum, const void *buf, size_t bufsize)
+{
+ size_t count;
+ if(!bignum) bignum = d0_bignum_new(); if(!bignum) return NULL;
+ mpz_import(bignum->z, bufsize, 1, 1, 0, 0, buf);
+ return bignum;
+}
+
d0_bignum_t *d0_bignum_new(void)
{
d0_bignum_t *b = d0_malloc(sizeof(d0_bignum_t));