1f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#include <tommath.h> 2f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef BN_MP_GET_INT_C 3f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* LibTomMath, multiple-precision integer library -- Tom St Denis 4f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 5f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * LibTomMath is a library that provides multiple-precision 6f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * integer arithmetic as well as number theoretic functionality. 7f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 8f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * The library was designed directly after the MPI library by 9f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * Michael Fromberger but has been written from scratch with 10f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * additional optimizations in place. 11f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 12f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * The library is free for all purposes without any express 13f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * guarantee it works. 14f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 15f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com 16f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project */ 17f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 18f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* get the lower 32-bits of an mp_int */ 19f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectunsigned long mp_get_int(mp_int * a) 20f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 21f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int i; 22f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project unsigned long res; 23f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 24f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (a->used == 0) { 25f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return 0; 26f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 27f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 28f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* get number of digits of the lsb we have to read */ 29f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project i = MIN(a->used,(int)((sizeof(unsigned long)*CHAR_BIT+DIGIT_BIT-1)/DIGIT_BIT))-1; 30f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 31f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* get most significant digit of result */ 32f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project res = DIGIT(a,i); 33f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 34f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project while (--i >= 0) { 35f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project res = (res << DIGIT_BIT) | DIGIT(a,i); 36f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 37f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 38f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project /* force result to 32-bits always so it is consistent on non 32-bit platforms */ 39f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return res & 0xFFFFFFFFUL; 40f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 41f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 42f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 43f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Source: /cvs/libtom/libtommath/bn_mp_get_int.c,v $ */ 44f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Revision: 1.3 $ */ 45f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Date: 2006/03/31 14:18:44 $ */ 46