From 6bf0a5cb5034a7e684dcc3500e841785237ce2dd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 19:32:43 +0200 Subject: Adding upstream version 1:115.7.0. Signed-off-by: Daniel Baumann --- comm/third_party/libgcrypt/mpi/mpi-scan.c | 130 ++++++++++++++++++++++++++++++ 1 file changed, 130 insertions(+) create mode 100644 comm/third_party/libgcrypt/mpi/mpi-scan.c (limited to 'comm/third_party/libgcrypt/mpi/mpi-scan.c') diff --git a/comm/third_party/libgcrypt/mpi/mpi-scan.c b/comm/third_party/libgcrypt/mpi/mpi-scan.c new file mode 100644 index 0000000000..e27f7faa99 --- /dev/null +++ b/comm/third_party/libgcrypt/mpi/mpi-scan.c @@ -0,0 +1,130 @@ +/* mpi-scan.c - MPI functions + * Copyright (C) 1998, 2001, 2002, 2003 Free Software Foundation, Inc. + * + * This file is part of Libgcrypt. + * + * Libgcrypt is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * Libgcrypt is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include +#include +#include +#include "mpi-internal.h" +#include "longlong.h" + +/**************** + * Scan through an mpi and return byte for byte. a -1 is returned to indicate + * the end of the mpi. Scanning is done from the lsb to the msb, returned + * values are in the range of 0 .. 255. + * + * FIXME: This code is VERY ugly! + */ +/* int */ +/* _gcry_mpi_getbyte( gcry_mpi_t a, unsigned idx ) */ +/* { */ +/* int i, j; */ +/* unsigned n; */ +/* mpi_ptr_t ap; */ +/* mpi_limb_t limb; */ + +/* ap = a->d; */ +/* for(n=0,i=0; i < a->nlimbs; i++ ) { */ +/* limb = ap[i]; */ +/* for( j=0; j < BYTES_PER_MPI_LIMB; j++, n++ ) */ +/* if( n == idx ) */ +/* return (limb >> j*8) & 0xff; */ +/* } */ +/* return -1; */ +/* } */ + + +/**************** + * Put a value at position IDX into A. idx counts from lsb to msb + */ +/* void */ +/* _gcry_mpi_putbyte( gcry_mpi_t a, unsigned idx, int xc ) */ +/* { */ +/* int i, j; */ +/* unsigned n; */ +/* mpi_ptr_t ap; */ +/* mpi_limb_t limb, c; */ + +/* c = xc & 0xff; */ +/* ap = a->d; */ +/* for(n=0,i=0; i < a->alloced; i++ ) { */ +/* limb = ap[i]; */ +/* for( j=0; j < BYTES_PER_MPI_LIMB; j++, n++ ) */ +/* if( n == idx ) { */ +/* #if BYTES_PER_MPI_LIMB == 4 */ +/* if( j == 0 ) */ +/* limb = (limb & 0xffffff00) | c; */ +/* else if( j == 1 ) */ +/* limb = (limb & 0xffff00ff) | (c<<8); */ +/* else if( j == 2 ) */ +/* limb = (limb & 0xff00ffff) | (c<<16); */ +/* else */ +/* limb = (limb & 0x00ffffff) | (c<<24); */ +/* #elif BYTES_PER_MPI_LIMB == 8 */ +/* if( j == 0 ) */ +/* limb = (limb & 0xffffffffffffff00) | c; */ +/* else if( j == 1 ) */ +/* limb = (limb & 0xffffffffffff00ff) | (c<<8); */ +/* else if( j == 2 ) */ +/* limb = (limb & 0xffffffffff00ffff) | (c<<16); */ +/* else if( j == 3 ) */ +/* limb = (limb & 0xffffffff00ffffff) | (c<<24); */ +/* else if( j == 4 ) */ +/* limb = (limb & 0xffffff00ffffffff) | (c<<32); */ +/* else if( j == 5 ) */ +/* limb = (limb & 0xffff00ffffffffff) | (c<<40); */ +/* else if( j == 6 ) */ +/* limb = (limb & 0xff00ffffffffffff) | (c<<48); */ +/* else */ +/* limb = (limb & 0x00ffffffffffffff) | (c<<56); */ +/* #else */ +/* #error please enhance this function, its ugly - i know. */ +/* #endif */ +/* if( a->nlimbs <= i ) */ +/* a->nlimbs = i+1; */ +/* ap[i] = limb; */ +/* return; */ +/* } */ +/* } */ +/* abort(); /\* index out of range *\/ */ +/* } */ + + +/**************** + * Count the number of zerobits at the low end of A + */ +unsigned +_gcry_mpi_trailing_zeros( gcry_mpi_t a ) +{ + unsigned n, count = 0; + + for(n=0; n < a->nlimbs; n++ ) { + if( a->d[n] ) { + unsigned nn; + mpi_limb_t alimb = a->d[n]; + + count_trailing_zeros( nn, alimb ); + count += nn; + break; + } + count += BITS_PER_MPI_LIMB; + } + return count; + +} -- cgit v1.2.3