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authorMauro Carvalho Chehab <mchehab@redhat.com>2012-03-23 08:06:43 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2012-03-23 08:06:43 -0300
commit7483d45f0aee3afc0646d185cabd4af9f6cab58c (patch)
treea312f7d77c34748bec62f0431df33007b10e4e7f /lib/mpi/generic_mpih-rshift.c
parent3e85fc1b9fc1c7e20b9a01f2314bb633bb10501a (diff)
parentf92c97c8bd77992ff8bd6ef29a23dc82dca799cb (diff)
Merge branch 'staging/for_v3.4' into v4l_for_linus
* staging/for_v3.4: (10117 commits) [media] update CARDLIST.em28xx [media] partially reverts changeset fa5527c [media] stb0899: fix the limits for signal strength values [media] em28xx: support for 2304:0242 PCTV QuatroStick (510e) [media] em28xx: support for 2013:0251 PCTV QuatroStick nano (520e) [media] -EINVAL -> -ENOTTY [media] gspca - sn9c20x: Cleanup source [media] gspca - sn9c20x: Simplify register write for capture start/stop [media] gspca - sn9c20x: Add automatic JPEG compression mechanism [media] gspca - sn9c20x: Greater delay in case of sensor no response [media] gspca - sn9c20x: Optimize the code of write sequences [media] gspca - sn9c20x: Add the JPEG compression quality control [media] gspca - sn9c20x: Add a delay after Omnivision sensor reset [media] gspca - sn9c20x: Propagate USB errors to higher level [media] gspca - sn9c20x: Use the new video control mechanism [media] gspca - sn9c20x: Fix loss of frame start [media] gspca - zc3xx: Lack of register 08 value for sensor cs2102k [media] gspca - ov534_9: Add brightness to OmniVision 5621 sensor [media] gspca - zc3xx: Add V4L2_CID_JPEG_COMPRESSION_QUALITY control support [media] pvrusb2: fix 7MHz & 8MHz DVB-T tuner support for HVR1900 rev D1F5 ...
Diffstat (limited to 'lib/mpi/generic_mpih-rshift.c')
-rw-r--r--lib/mpi/generic_mpih-rshift.c63
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diff --git a/lib/mpi/generic_mpih-rshift.c b/lib/mpi/generic_mpih-rshift.c
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+/* mpih-rshift.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1998, 1999,
+ * 2000, 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
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * 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 limbs long) CNT bits to the right
+ * and store the USIZE least significant limbs of the result at WP.
+ * The bits shifted out to the right are returned.
+ *
+ * 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_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned 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;
+ high_limb = up[0];
+ retval = high_limb << sh_2;
+ low_limb = high_limb;
+ for (i = 1; i < usize; i++) {
+ high_limb = up[i];
+ wp[i] = (low_limb >> sh_1) | (high_limb << sh_2);
+ low_limb = high_limb;
+ }
+ wp[i] = low_limb >> sh_1;
+
+ return retval;
+}