mpi-genesis 1
mpi-genesis 2 * Copyright (C) 1994, 1996, 1998, 1999 Free Software Foundation, Inc.
mpi-genesis 3 *
mpi-genesis 4 * This file is part of GnuPG.
mpi-genesis 5 *
mpi-genesis 6 * GnuPG is free software; you can redistribute it and/or modify
mpi-genesis 7 * it under the terms of the GNU General Public License as published by
mpi-genesis 8 * the Free Software Foundation; either version 3 of the License, or
mpi-genesis 9 * (at your option) any later version.
mpi-genesis 10 *
mpi-genesis 11 * GnuPG is distributed in the hope that it will be useful,
mpi-genesis 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
mpi-genesis 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
mpi-genesis 14 * GNU General Public License for more details.
mpi-genesis 15 *
mpi-genesis 16 * You should have received a copy of the GNU General Public License
mpi-genesis 17 * along with this program; if not, see <http:
mpi-genesis 18 *
mpi-genesis 19 * Note: This code is heavily based on the GNU MP Library.
mpi-genesis 20 * Actually it's the same code with only minor changes in the
mpi-genesis 21 * way the data is stored; this is to support the abstraction
mpi-genesis 22 * of an optional secure memory allocation which may be used
mpi-genesis 23 * to avoid revealing of sensitive data due to paging etc.
mpi-genesis 24 * The GNU MP Library itself is published under the LGPL;
mpi-genesis 25 * however I decided to publish this code under the plain GPL.
mpi-genesis 26 */
mpi-genesis 27
mpi-genesis 28 #ifndef G10_MPI_INLINE_H
mpi-genesis 29 #define G10_MPI_INLINE_H
mpi-genesis 30
mpi-genesis 31 #ifndef G10_MPI_INLINE_DECL
mpi-genesis 32 #define G10_MPI_INLINE_DECL extern __inline__
mpi-genesis 33 #endif
mpi-genesis 34
mpi-genesis 35 G10_MPI_INLINE_DECL mpi_limb_t
mpi-genesis 36 mpihelp_add_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi-genesis 37 mpi_size_t s1_size, mpi_limb_t s2_limb)
mpi-genesis 38 {
mpi-genesis 39 mpi_limb_t x;
mpi-genesis 40
mpi-genesis 41 x = *s1_ptr++;
mpi-genesis 42 s2_limb += x;
mpi-genesis 43 *res_ptr++ = s2_limb;
mpi-genesis 44 if( s2_limb < x ) {
mpi-genesis 45 while( --s1_size ) {
mpi-genesis 46 x = *s1_ptr++ + 1;
mpi-genesis 47 *res_ptr++ = x;
mpi-genesis 48 if( x )
mpi-genesis 49 goto leave;
mpi-genesis 50 }
mpi-genesis 51 return 1;
mpi-genesis 52 }
mpi-genesis 53
mpi-genesis 54 leave:
mpi-genesis 55 if( res_ptr != s1_ptr ) {
mpi-genesis 56 mpi_size_t i;
mpi-genesis 57 for( i=0; i < s1_size-1; i++ )
mpi-genesis 58 res_ptr[i] = s1_ptr[i];
mpi-genesis 59 }
mpi-genesis 60 return 0;
mpi-genesis 61 }
mpi-genesis 62
mpi-genesis 63
mpi-genesis 64
mpi-genesis 65 G10_MPI_INLINE_DECL mpi_limb_t
mpi-genesis 66 mpihelp_add(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
mpi-genesis 67 mpi_ptr_t s2_ptr, mpi_size_t s2_size)
mpi-genesis 68 {
mpi-genesis 69 mpi_limb_t cy = 0;
mpi-genesis 70
mpi-genesis 71 if( s2_size )
mpi-genesis 72 cy = mpihelp_add_n( res_ptr, s1_ptr, s2_ptr, s2_size );
mpi-genesis 73
mpi-genesis 74 if( s1_size - s2_size )
mpi-genesis 75 cy = mpihelp_add_1( res_ptr + s2_size, s1_ptr + s2_size,
mpi-genesis 76 s1_size - s2_size, cy);
mpi-genesis 77 return cy;
mpi-genesis 78 }
mpi-genesis 79
mpi-genesis 80
mpi-genesis 81 G10_MPI_INLINE_DECL mpi_limb_t
mpi-genesis 82 mpihelp_sub_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
mpi-genesis 83 mpi_size_t s1_size, mpi_limb_t s2_limb )
mpi-genesis 84 {
mpi-genesis 85 mpi_limb_t x;
mpi-genesis 86
mpi-genesis 87 x = *s1_ptr++;
mpi-genesis 88 s2_limb = x - s2_limb;
mpi-genesis 89 *res_ptr++ = s2_limb;
mpi-genesis 90 if( s2_limb > x ) {
mpi-genesis 91 while( --s1_size ) {
mpi-genesis 92 x = *s1_ptr++;
mpi-genesis 93 *res_ptr++ = x - 1;
mpi-genesis 94 if( x )
mpi-genesis 95 goto leave;
mpi-genesis 96 }
mpi-genesis 97 return 1;
mpi-genesis 98 }
mpi-genesis 99
mpi-genesis 100 leave:
mpi-genesis 101 if( res_ptr != s1_ptr ) {
mpi-genesis 102 mpi_size_t i;
mpi-genesis 103 for( i=0; i < s1_size-1; i++ )
mpi-genesis 104 res_ptr[i] = s1_ptr[i];
mpi-genesis 105 }
mpi-genesis 106 return 0;
mpi-genesis 107 }
mpi-genesis 108
mpi-genesis 109
mpi-genesis 110
mpi-genesis 111 G10_MPI_INLINE_DECL mpi_limb_t
mpi-genesis 112 mpihelp_sub( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size,
mpi-genesis 113 mpi_ptr_t s2_ptr, mpi_size_t s2_size)
mpi-genesis 114 {
mpi-genesis 115 mpi_limb_t cy = 0;
mpi-genesis 116
mpi-genesis 117 if( s2_size )
mpi-genesis 118 cy = mpihelp_sub_n(res_ptr, s1_ptr, s2_ptr, s2_size);
mpi-genesis 119
mpi-genesis 120 if( s1_size - s2_size )
mpi-genesis 121 cy = mpihelp_sub_1(res_ptr + s2_size, s1_ptr + s2_size,
mpi-genesis 122 s1_size - s2_size, cy);
mpi-genesis 123 return cy;
mpi-genesis 124 }
mpi-genesis 125
mpi-genesis 126 #endif /*G10_MPI_INLINE_H*/