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math.big: implement big.integer in V (#11352)
This commit is contained in:
Subhomoy Haldar
2
thirdparty/bignum/README.md
vendored
2
thirdparty/bignum/README.md
vendored
@ -1,2 +0,0 @@
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This folder contains bn.h and bn.c files
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from https://github.com/kokke/tiny-bignum-c
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664
thirdparty/bignum/bn.c
vendored
664
thirdparty/bignum/bn.c
vendored
@ -1,664 +0,0 @@
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/*
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Big number library - arithmetic on multiple-precision unsigned integers.
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This library is an implementation of arithmetic on arbitrarily large integers.
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The difference between this and other implementations, is that the data structure
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has optimal memory utilization (i.e. a 1024 bit integer takes up 128 bytes RAM),
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and all memory is allocated statically: no dynamic allocation for better or worse.
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Primary goals are correctness, clarity of code and clean, portable implementation.
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Secondary goal is a memory footprint small enough to make it suitable for use in
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embedded applications.
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The current state is correct functionality and adequate performance.
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There may well be room for performance-optimizations and improvements.
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*/
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#include <stdio.h>
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#include <stdbool.h>
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#include <assert.h>
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#include "bn.h"
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/* Functions for shifting number in-place. */
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static void _lshift_one_bit(struct bn* a);
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static void _rshift_one_bit(struct bn* a);
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static void _lshift_word(struct bn* a, int nwords);
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static void _rshift_word(struct bn* a, int nwords);
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/* Public / Exported functions. */
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void bignum_init(struct bn* n)
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{
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require(n, "n is null");
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int i;
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for (i = 0; i < BN_ARRAY_SIZE; ++i)
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{
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n->array[i] = 0;
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}
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}
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void bignum_from_int(struct bn* n, DTYPE_TMP i)
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{
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require(n, "n is null");
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bignum_init(n);
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/* Endianness issue if machine is not little-endian? */
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#ifdef WORD_SIZE
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#if (WORD_SIZE == 1)
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n->array[0] = (i & 0x000000ff);
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n->array[1] = (i & 0x0000ff00) >> 8;
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n->array[2] = (i & 0x00ff0000) >> 16;
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n->array[3] = (i & 0xff000000) >> 24;
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#elif (WORD_SIZE == 2)
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n->array[0] = (i & 0x0000ffff);
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n->array[1] = (i & 0xffff0000) >> 16;
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#elif (WORD_SIZE == 4)
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n->array[0] = i;
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DTYPE_TMP num_32 = 32;
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DTYPE_TMP tmp = i >> num_32; /* bit-shift with U64 operands to force 64-bit results */
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n->array[1] = tmp;
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#endif
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#endif
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}
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int bignum_to_int(struct bn* n)
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{
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require(n, "n is null");
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int ret = 0;
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/* Endianness issue if machine is not little-endian? */
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#if (WORD_SIZE == 1)
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ret += n->array[0];
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ret += n->array[1] << 8;
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ret += n->array[2] << 16;
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ret += n->array[3] << 24;
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#elif (WORD_SIZE == 2)
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ret += n->array[0];
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ret += n->array[1] << 16;
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#elif (WORD_SIZE == 4)
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ret += n->array[0];
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#endif
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return ret;
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}
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void bignum_from_string(struct bn* n, char* str, int nbytes)
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{
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require(n, "n is null");
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require(str, "str is null");
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require(nbytes > 0, "nbytes must be positive");
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require((nbytes & 1) == 0, "string format must be in hex -> equal number of bytes");
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bignum_init(n);
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DTYPE tmp; /* DTYPE is defined in bn.h - uint{8,16,32,64}_t */
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int i = nbytes - (2 * WORD_SIZE); /* index into string */
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int j = 0; /* index into array */
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/* reading last hex-byte "MSB" from string first -> big endian */
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/* MSB ~= most significant byte / block ? :) */
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while (i >= 0)
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{
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tmp = 0;
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sscanf(&str[i], SSCANF_FORMAT_STR, &tmp);
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n->array[j] = tmp;
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i -= (2 * WORD_SIZE); /* step WORD_SIZE hex-byte(s) back in the string. */
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j += 1; /* step one element forward in the array. */
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}
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}
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void bignum_to_string(struct bn* n, char* str, int nbytes)
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{
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require(n, "n is null");
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require(str, "str is null");
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require(nbytes > 0, "nbytes must be positive");
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require((nbytes & 1) == 0, "string format must be in hex -> equal number of bytes");
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int j = BN_ARRAY_SIZE - 1; /* index into array - reading "MSB" first -> big-endian */
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int i = 0; /* index into string representation. */
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/* reading last array-element "MSB" first -> big endian */
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while ((j >= 0) && (nbytes > (i + 1)))
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{
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sprintf(&str[i], SPRINTF_FORMAT_STR, n->array[j]);
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i += (2 * WORD_SIZE); /* step WORD_SIZE hex-byte(s) forward in the string. */
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j -= 1; /* step one element back in the array. */
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}
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/* Count leading zeros: */
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j = 0;
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while (str[j] == '0')
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{
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j += 1;
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}
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/* Move string j places ahead, effectively skipping leading zeros */
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for (i = 0; i < (nbytes - j); ++i)
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{
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str[i] = str[i + j];
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}
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/* Zero-terminate string */
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str[i] = 0;
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}
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void bignum_dec(struct bn* n)
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{
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require(n, "n is null");
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DTYPE tmp; /* copy of n */
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DTYPE res;
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int i;
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for (i = 0; i < BN_ARRAY_SIZE; ++i)
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{
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tmp = n->array[i];
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res = tmp - 1;
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n->array[i] = res;
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if (!(res > tmp))
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{
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break;
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}
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}
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}
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void bignum_inc(struct bn* n)
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{
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require(n, "n is null");
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DTYPE res;
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DTYPE_TMP tmp; /* copy of n */
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int i;
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for (i = 0; i < BN_ARRAY_SIZE; ++i)
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{
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tmp = n->array[i];
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res = tmp + 1;
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n->array[i] = res;
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if (res > tmp)
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{
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break;
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}
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}
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}
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void bignum_add(struct bn* a, struct bn* b, struct bn* c)
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{
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require(a, "a is null");
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require(b, "b is null");
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require(c, "c is null");
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DTYPE_TMP tmp;
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int carry = 0;
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int i;
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for (i = 0; i < BN_ARRAY_SIZE; ++i)
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{
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tmp = (DTYPE_TMP)a->array[i] + b->array[i] + carry;
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carry = (tmp > MAX_VAL);
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c->array[i] = (tmp & MAX_VAL);
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}
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}
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void bignum_sub(struct bn* a, struct bn* b, struct bn* c)
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{
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require(a, "a is null");
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require(b, "b is null");
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require(c, "c is null");
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DTYPE_TMP res;
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DTYPE_TMP tmp1;
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DTYPE_TMP tmp2;
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int borrow = 0;
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int i;
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for (i = 0; i < BN_ARRAY_SIZE; ++i)
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{
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tmp1 = (DTYPE_TMP)a->array[i] + (MAX_VAL + 1); /* + number_base */
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tmp2 = (DTYPE_TMP)b->array[i] + borrow;;
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res = (tmp1 - tmp2);
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c->array[i] = (DTYPE)(res & MAX_VAL); /* "modulo number_base" == "% (number_base - 1)" if number_base is 2^N */
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borrow = (res <= MAX_VAL);
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}
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}
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void bignum_mul(struct bn* a, struct bn* b, struct bn* c)
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{
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require(a, "a is null");
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require(b, "b is null");
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require(c, "c is null");
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struct bn row;
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struct bn tmp;
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int i, j;
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bignum_init(c);
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for (i = 0; i < BN_ARRAY_SIZE; ++i)
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{
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bignum_init(&row);
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for (j = 0; j < BN_ARRAY_SIZE; ++j)
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{
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if (i + j < BN_ARRAY_SIZE)
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{
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bignum_init(&tmp);
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DTYPE_TMP intermediate = ((DTYPE_TMP)a->array[i] * (DTYPE_TMP)b->array[j]);
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bignum_from_int(&tmp, intermediate);
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_lshift_word(&tmp, i + j);
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bignum_add(&tmp, &row, &row);
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}
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}
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bignum_add(c, &row, c);
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}
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}
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void bignum_div(struct bn* a, struct bn* b, struct bn* c)
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{
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require(a, "a is null");
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require(b, "b is null");
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require(c, "c is null");
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struct bn current;
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struct bn denom;
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struct bn tmp;
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bignum_from_int(¤t, 1); // int current = 1;
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bignum_assign(&denom, b); // denom = b
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bignum_assign(&tmp, a); // tmp = a
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const DTYPE_TMP half_max = 1 + (DTYPE_TMP)(MAX_VAL / 2);
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bool overflow = false;
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while (bignum_cmp(&denom, a) != LARGER) // while (denom <= a) {
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{
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if (denom.array[BN_ARRAY_SIZE - 1] >= half_max)
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{
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overflow = true;
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break;
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}
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_lshift_one_bit(¤t); // current <<= 1;
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_lshift_one_bit(&denom); // denom <<= 1;
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}
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if (!overflow)
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{
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_rshift_one_bit(&denom); // denom >>= 1;
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_rshift_one_bit(¤t); // current >>= 1;
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}
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bignum_init(c); // int answer = 0;
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while (!bignum_is_zero(¤t)) // while (current != 0)
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{
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if (bignum_cmp(&tmp, &denom) != SMALLER) // if (dividend >= denom)
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{
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bignum_sub(&tmp, &denom, &tmp); // dividend -= denom;
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bignum_or(c, ¤t, c); // answer |= current;
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}
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_rshift_one_bit(¤t); // current >>= 1;
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_rshift_one_bit(&denom); // denom >>= 1;
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} // return answer;
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}
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void bignum_lshift(struct bn* a, struct bn* b, int nbits)
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{
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require(a, "a is null");
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require(b, "b is null");
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require(nbits >= 0, "no negative shifts");
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bignum_assign(b, a);
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/* Handle shift in multiples of word-size */
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const int nbits_pr_word = (WORD_SIZE * 8);
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int nwords = nbits / nbits_pr_word;
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if (nwords != 0)
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{
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_lshift_word(b, nwords);
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nbits -= (nwords * nbits_pr_word);
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}
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if (nbits != 0)
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{
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int i;
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for (i = (BN_ARRAY_SIZE - 1); i > 0; --i)
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{
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b->array[i] = (b->array[i] << nbits) | (b->array[i - 1] >> ((8 * WORD_SIZE) - nbits));
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}
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b->array[i] <<= nbits;
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}
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}
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void bignum_rshift(struct bn* a, struct bn* b, int nbits)
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{
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require(a, "a is null");
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require(b, "b is null");
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require(nbits >= 0, "no negative shifts");
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bignum_assign(b, a);
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/* Handle shift in multiples of word-size */
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const int nbits_pr_word = (WORD_SIZE * 8);
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int nwords = nbits / nbits_pr_word;
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if (nwords != 0)
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{
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_rshift_word(b, nwords);
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nbits -= (nwords * nbits_pr_word);
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}
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||||
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||||
if (nbits != 0)
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{
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int i;
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for (i = 0; i < (BN_ARRAY_SIZE - 1); ++i)
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{
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b->array[i] = (b->array[i] >> nbits) | (b->array[i + 1] << ((8 * WORD_SIZE) - nbits));
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}
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b->array[i] >>= nbits;
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}
|
||||
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||||
}
|
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|
||||
|
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void bignum_mod(struct bn* a, struct bn* b, struct bn* c)
|
||||
{
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||||
/*
|
||||
Take divmod and throw away div part
|
||||
*/
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
require(c, "c is null");
|
||||
|
||||
struct bn tmp;
|
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|
||||
bignum_divmod(a,b,&tmp,c);
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}
|
||||
|
||||
void bignum_divmod(struct bn* a, struct bn* b, struct bn* c, struct bn* d)
|
||||
{
|
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/*
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Puts a%b in d
|
||||
and a/b in c
|
||||
|
||||
mod(a,b) = a - ((a / b) * b)
|
||||
|
||||
example:
|
||||
mod(8, 3) = 8 - ((8 / 3) * 3) = 2
|
||||
*/
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
require(c, "c is null");
|
||||
|
||||
struct bn tmp;
|
||||
|
||||
/* c = (a / b) */
|
||||
bignum_div(a, b, c);
|
||||
|
||||
/* tmp = (c * b) */
|
||||
bignum_mul(c, b, &tmp);
|
||||
|
||||
/* c = a - tmp */
|
||||
bignum_sub(a, &tmp, d);
|
||||
}
|
||||
|
||||
|
||||
void bignum_and(struct bn* a, struct bn* b, struct bn* c)
|
||||
{
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
require(c, "c is null");
|
||||
|
||||
int i;
|
||||
for (i = 0; i < BN_ARRAY_SIZE; ++i)
|
||||
{
|
||||
c->array[i] = (a->array[i] & b->array[i]);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
void bignum_or(struct bn* a, struct bn* b, struct bn* c)
|
||||
{
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
require(c, "c is null");
|
||||
|
||||
int i;
|
||||
for (i = 0; i < BN_ARRAY_SIZE; ++i)
|
||||
{
|
||||
c->array[i] = (a->array[i] | b->array[i]);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
void bignum_xor(struct bn* a, struct bn* b, struct bn* c)
|
||||
{
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
require(c, "c is null");
|
||||
|
||||
int i;
|
||||
for (i = 0; i < BN_ARRAY_SIZE; ++i)
|
||||
{
|
||||
c->array[i] = (a->array[i] ^ b->array[i]);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
int bignum_cmp(struct bn* a, struct bn* b)
|
||||
{
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
|
||||
int i = BN_ARRAY_SIZE;
|
||||
do
|
||||
{
|
||||
i -= 1; /* Decrement first, to start with last array element */
|
||||
if (a->array[i] > b->array[i])
|
||||
{
|
||||
return LARGER;
|
||||
}
|
||||
else if (a->array[i] < b->array[i])
|
||||
{
|
||||
return SMALLER;
|
||||
}
|
||||
}
|
||||
while (i != 0);
|
||||
|
||||
return EQUAL;
|
||||
}
|
||||
|
||||
|
||||
int bignum_is_zero(struct bn* n)
|
||||
{
|
||||
require(n, "n is null");
|
||||
|
||||
int i;
|
||||
for (i = 0; i < BN_ARRAY_SIZE; ++i)
|
||||
{
|
||||
if (n->array[i])
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
|
||||
void bignum_pow(struct bn* a, struct bn* b, struct bn* c)
|
||||
{
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
require(c, "c is null");
|
||||
|
||||
struct bn tmp;
|
||||
|
||||
bignum_init(c);
|
||||
|
||||
if (bignum_cmp(b, c) == EQUAL)
|
||||
{
|
||||
/* Return 1 when exponent is 0 -- n^0 = 1 */
|
||||
bignum_inc(c);
|
||||
}
|
||||
else
|
||||
{
|
||||
struct bn bcopy;
|
||||
bignum_assign(&bcopy, b);
|
||||
|
||||
/* Copy a -> tmp */
|
||||
bignum_assign(&tmp, a);
|
||||
|
||||
bignum_dec(&bcopy);
|
||||
|
||||
/* Begin summing products: */
|
||||
while (!bignum_is_zero(&bcopy))
|
||||
{
|
||||
|
||||
/* c = tmp * tmp */
|
||||
bignum_mul(&tmp, a, c);
|
||||
/* Decrement b by one */
|
||||
bignum_dec(&bcopy);
|
||||
|
||||
bignum_assign(&tmp, c);
|
||||
}
|
||||
|
||||
/* c = tmp */
|
||||
bignum_assign(c, &tmp);
|
||||
}
|
||||
}
|
||||
|
||||
void bignum_isqrt(struct bn *a, struct bn* b)
|
||||
{
|
||||
require(a, "a is null");
|
||||
require(b, "b is null");
|
||||
|
||||
struct bn low, high, mid, tmp;
|
||||
|
||||
bignum_init(&low);
|
||||
bignum_assign(&high, a);
|
||||
bignum_rshift(&high, &mid, 1);
|
||||
bignum_inc(&mid);
|
||||
|
||||
while (bignum_cmp(&high, &low) > 0)
|
||||
{
|
||||
bignum_mul(&mid, &mid, &tmp);
|
||||
if (bignum_cmp(&tmp, a) > 0)
|
||||
{
|
||||
bignum_assign(&high, &mid);
|
||||
bignum_dec(&high);
|
||||
}
|
||||
else
|
||||
{
|
||||
bignum_assign(&low, &mid);
|
||||
}
|
||||
bignum_sub(&high,&low,&mid);
|
||||
_rshift_one_bit(&mid);
|
||||
bignum_add(&low,&mid,&mid);
|
||||
bignum_inc(&mid);
|
||||
}
|
||||
bignum_assign(b,&low);
|
||||
}
|
||||
|
||||
|
||||
void bignum_assign(struct bn* dst, struct bn* src)
|
||||
{
|
||||
require(dst, "dst is null");
|
||||
require(src, "src is null");
|
||||
|
||||
int i;
|
||||
for (i = 0; i < BN_ARRAY_SIZE; ++i)
|
||||
{
|
||||
dst->array[i] = src->array[i];
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/* Private / Static functions. */
|
||||
static void _rshift_word(struct bn* a, int nwords)
|
||||
{
|
||||
/* Naive method: */
|
||||
require(a, "a is null");
|
||||
require(nwords >= 0, "no negative shifts");
|
||||
|
||||
int i;
|
||||
if (nwords >= BN_ARRAY_SIZE)
|
||||
{
|
||||
for (i = 0; i < BN_ARRAY_SIZE; ++i)
|
||||
{
|
||||
a->array[i] = 0;
|
||||
}
|
||||
return;
|
||||
}
|
||||
|
||||
for (i = 0; i < BN_ARRAY_SIZE - nwords; ++i)
|
||||
{
|
||||
a->array[i] = a->array[i + nwords];
|
||||
}
|
||||
for (; i < BN_ARRAY_SIZE; ++i)
|
||||
{
|
||||
a->array[i] = 0;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void _lshift_word(struct bn* a, int nwords)
|
||||
{
|
||||
require(a, "a is null");
|
||||
require(nwords >= 0, "no negative shifts");
|
||||
|
||||
int i;
|
||||
/* Shift whole words */
|
||||
for (i = (BN_ARRAY_SIZE - 1); i >= nwords; --i)
|
||||
{
|
||||
a->array[i] = a->array[i - nwords];
|
||||
}
|
||||
/* Zero pad shifted words. */
|
||||
for (; i >= 0; --i)
|
||||
{
|
||||
a->array[i] = 0;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void _lshift_one_bit(struct bn* a)
|
||||
{
|
||||
require(a, "a is null");
|
||||
|
||||
int i;
|
||||
for (i = (BN_ARRAY_SIZE - 1); i > 0; --i)
|
||||
{
|
||||
a->array[i] = (a->array[i] << 1) | (a->array[i - 1] >> ((8 * WORD_SIZE) - 1));
|
||||
}
|
||||
a->array[0] <<= 1;
|
||||
}
|
||||
|
||||
|
||||
static void _rshift_one_bit(struct bn* a)
|
||||
{
|
||||
require(a, "a is null");
|
||||
|
||||
int i;
|
||||
for (i = 0; i < (BN_ARRAY_SIZE - 1); ++i)
|
||||
{
|
||||
a->array[i] = (a->array[i] >> 1) | (a->array[i + 1] << ((8 * WORD_SIZE) - 1));
|
||||
}
|
||||
a->array[BN_ARRAY_SIZE - 1] >>= 1;
|
||||
}
|
||||
|
||||
|
||||
123
thirdparty/bignum/bn.h
vendored
123
thirdparty/bignum/bn.h
vendored
@ -1,123 +0,0 @@
|
||||
#ifndef __BIGNUM_H__
|
||||
#define __BIGNUM_H__
|
||||
/*
|
||||
|
||||
Big number library - arithmetic on multiple-precision unsigned integers.
|
||||
|
||||
This library is an implementation of arithmetic on arbitrarily large integers.
|
||||
|
||||
The difference between this and other implementations, is that the data structure
|
||||
has optimal memory utilization (i.e. a 1024 bit integer takes up 128 bytes RAM),
|
||||
and all memory is allocated statically: no dynamic allocation for better or worse.
|
||||
|
||||
Primary goals are correctness, clarity of code and clean, portable implementation.
|
||||
Secondary goal is a memory footprint small enough to make it suitable for use in
|
||||
embedded applications.
|
||||
|
||||
|
||||
The current state is correct functionality and adequate performance.
|
||||
There may well be room for performance-optimizations and improvements.
|
||||
|
||||
*/
|
||||
|
||||
#include <stdint.h>
|
||||
#include <assert.h>
|
||||
|
||||
|
||||
/* This macro defines the word size in bytes of the array that constitues the big-number data structure. */
|
||||
#ifndef WORD_SIZE
|
||||
#define WORD_SIZE 4
|
||||
#endif
|
||||
|
||||
/* Size of big-numbers in bytes */
|
||||
#define BN_ARRAY_SIZE (128 / WORD_SIZE)
|
||||
|
||||
|
||||
/* Here comes the compile-time specialization for how large the underlying array size should be. */
|
||||
/* The choices are 1, 2 and 4 bytes in size with uint32, uint64 for WORD_SIZE==4, as temporary. */
|
||||
#ifndef WORD_SIZE
|
||||
#error Must define WORD_SIZE to be 1, 2, 4
|
||||
#elif (WORD_SIZE == 1)
|
||||
/* Data type of array in structure */
|
||||
#define DTYPE uint8_t
|
||||
/* bitmask for getting MSB */
|
||||
#define DTYPE_MSB ((DTYPE_TMP)(0x80))
|
||||
/* Data-type larger than DTYPE, for holding intermediate results of calculations */
|
||||
#define DTYPE_TMP uint32_t
|
||||
/* sprintf format string */
|
||||
#define SPRINTF_FORMAT_STR "%.02x"
|
||||
#define SSCANF_FORMAT_STR "%2hhx"
|
||||
/* Max value of integer type */
|
||||
#define MAX_VAL ((DTYPE_TMP)0xFF)
|
||||
#elif (WORD_SIZE == 2)
|
||||
#define DTYPE uint16_t
|
||||
#define DTYPE_TMP uint32_t
|
||||
#define DTYPE_MSB ((DTYPE_TMP)(0x8000))
|
||||
#define SPRINTF_FORMAT_STR "%.04x"
|
||||
#define SSCANF_FORMAT_STR "%4hx"
|
||||
#define MAX_VAL ((DTYPE_TMP)0xFFFF)
|
||||
#elif (WORD_SIZE == 4)
|
||||
#define DTYPE uint32_t
|
||||
#define DTYPE_TMP uint64_t
|
||||
#define DTYPE_MSB ((DTYPE_TMP)(0x80000000))
|
||||
#define SPRINTF_FORMAT_STR "%.08x"
|
||||
#define SSCANF_FORMAT_STR "%8x"
|
||||
#define MAX_VAL ((DTYPE_TMP)0xFFFFFFFF)
|
||||
#endif
|
||||
#ifndef DTYPE
|
||||
#error DTYPE must be defined to uint8_t, uint16_t uint32_t or whatever
|
||||
#endif
|
||||
|
||||
|
||||
/* Custom assert macro - easy to disable */
|
||||
#define require(p, msg) assert(p && #msg)
|
||||
|
||||
|
||||
/* Data-holding structure: array of DTYPEs */
|
||||
struct bn
|
||||
{
|
||||
DTYPE array[BN_ARRAY_SIZE];
|
||||
};
|
||||
|
||||
|
||||
|
||||
/* Tokens returned by bignum_cmp() for value comparison */
|
||||
enum { SMALLER = -1, EQUAL = 0, LARGER = 1 };
|
||||
|
||||
|
||||
|
||||
/* Initialization functions: */
|
||||
void bignum_init(struct bn* n);
|
||||
void bignum_from_int(struct bn* n, DTYPE_TMP i);
|
||||
int bignum_to_int(struct bn* n);
|
||||
void bignum_from_string(struct bn* n, char* str, int nbytes);
|
||||
void bignum_to_string(struct bn* n, char* str, int maxsize);
|
||||
|
||||
/* Basic arithmetic operations: */
|
||||
void bignum_add(struct bn* a, struct bn* b, struct bn* c); /* c = a + b */
|
||||
void bignum_sub(struct bn* a, struct bn* b, struct bn* c); /* c = a - b */
|
||||
void bignum_mul(struct bn* a, struct bn* b, struct bn* c); /* c = a * b */
|
||||
void bignum_div(struct bn* a, struct bn* b, struct bn* c); /* c = a / b */
|
||||
void bignum_mod(struct bn* a, struct bn* b, struct bn* c); /* c = a % b */
|
||||
void bignum_divmod(struct bn* a, struct bn* b, struct bn* c, struct bn* d); /* c = a/b, d = a%b */
|
||||
|
||||
/* Bitwise operations: */
|
||||
void bignum_and(struct bn* a, struct bn* b, struct bn* c); /* c = a & b */
|
||||
void bignum_or(struct bn* a, struct bn* b, struct bn* c); /* c = a | b */
|
||||
void bignum_xor(struct bn* a, struct bn* b, struct bn* c); /* c = a ^ b */
|
||||
void bignum_lshift(struct bn* a, struct bn* b, int nbits); /* b = a << nbits */
|
||||
void bignum_rshift(struct bn* a, struct bn* b, int nbits); /* b = a >> nbits */
|
||||
|
||||
/* Special operators and comparison */
|
||||
int bignum_cmp(struct bn* a, struct bn* b); /* Compare: returns LARGER, EQUAL or SMALLER */
|
||||
int bignum_is_zero(struct bn* n); /* For comparison with zero */
|
||||
void bignum_inc(struct bn* n); /* Increment: add one to n */
|
||||
void bignum_dec(struct bn* n); /* Decrement: subtract one from n */
|
||||
void bignum_pow(struct bn* a, struct bn* b, struct bn* c); /* Calculate a^b -- e.g. 2^10 => 1024 */
|
||||
void bignum_isqrt(struct bn* a, struct bn* b); /* Integer square root -- e.g. isqrt(5) => 2*/
|
||||
void bignum_assign(struct bn* dst, struct bn* src); /* Copy src into dst -- dst := src */
|
||||
|
||||
|
||||
#endif /* #ifndef __BIGNUM_H__ */
|
||||
|
||||
|
||||
Reference in New Issue
Block a user