cregit-Linux how code gets into the kernel

Release 4.12 lib/mpi/generic_mpih-lshift.c

Directory: lib/mpi
/* mpihelp-lshift.c  -  MPI helper functions
 * Copyright (C) 1994, 1996, 1998, 2001 Free Software Foundation, Inc.
 * This file is part of GnuPG.
 * GnuPG is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * GnuPG is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * GNU General Public License for more details.
 * You should have received a copy of the GNU 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
 * Note: This code is heavily based on the GNU MP Library.
 *       Actually it's the same code with only minor changes in the
 *       way the data is stored; this is to support the abstraction
 *       of an optional secure memory allocation which may be used
 *       to avoid revealing of sensitive data due to paging etc.
 *       The GNU MP Library itself is published under the LGPL;
 *       however I decided to publish this code under the plain GPL.

#include "mpi-internal.h"

/* Shift U (pointed to by UP and USIZE digits long) CNT bits to the left
 * and store the USIZE least significant digits of the result at WP.
 * Return the bits shifted out from the most significant digit.
 * Argument constraints:
 * 1. 0 < CNT < BITS_PER_MP_LIMB
 * 2. If the result is to be written over the input, WP must be >= UP.

mpi_limb_t mpihelp_lshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned int cnt) { mpi_limb_t high_limb, low_limb; unsigned sh_1, sh_2; mpi_size_t i; mpi_limb_t retval; sh_1 = cnt; wp += 1; sh_2 = BITS_PER_MPI_LIMB - sh_1; i = usize - 1; low_limb = up[i]; retval = low_limb >> sh_2; high_limb = low_limb; while (--i >= 0) { low_limb = up[i]; wp[i] = (high_limb << sh_1) | (low_limb >> sh_2); high_limb = low_limb; } wp[i] = high_limb << sh_1; return retval; }


Dmitry Kasatkin120100.00%1100.00%

Overall Contributors

Dmitry Kasatkin125100.00%1100.00%
Directory: lib/mpi
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.