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-rw-r--r--src/osmo-bsc/arfcn_range_encode.c340
1 files changed, 0 insertions, 340 deletions
diff --git a/src/osmo-bsc/arfcn_range_encode.c b/src/osmo-bsc/arfcn_range_encode.c
deleted file mode 100644
index 54d98a967..000000000
--- a/src/osmo-bsc/arfcn_range_encode.c
+++ /dev/null
@@ -1,340 +0,0 @@
-/* gsm 04.08 system information (si) encoding and decoding
- * 3gpp ts 04.08 version 7.21.0 release 1998 / etsi ts 100 940 v7.21.0 */
-
-/*
- * (C) 2012 Holger Hans Peter Freyther
- * (C) 2012 by On-Waves
- * All Rights Reserved
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as published by
- * the Free Software Foundation; either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program 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 Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <osmocom/bsc/arfcn_range_encode.h>
-#include <osmocom/bsc/debug.h>
-
-#include <osmocom/gsm/protocol/gsm_04_08.h>
-
-#include <osmocom/core/utils.h>
-
-#include <errno.h>
-
-static inline int greatest_power_of_2_lesser_or_equal_to(int index)
-{
- int power_of_2 = 1;
-
- do {
- power_of_2 *= 2;
- } while (power_of_2 <= index);
-
- /* now go back one step */
- return power_of_2 / 2;
-}
-
-static inline int mod(int data, int range)
-{
- int res = data % range;
- while (res < 0)
- res += range;
- return res;
-}
-
-/**
- * Determine at which index to split the ARFCNs to create an
- * equally size partition for the given range. Return -1 if
- * no such partition exists.
- */
-int range_enc_find_index(enum gsm48_range range, const int *freqs, const int size)
-{
- int i, j, n;
-
- const int RANGE_DELTA = (range - 1) / 2;
-
- for (i = 0; i < size; ++i) {
- n = 0;
- for (j = 0; j < size; ++j) {
- if (mod(freqs[j] - freqs[i], range) <= RANGE_DELTA)
- n += 1;
- }
-
- if (n - 1 == (size - 1) / 2)
- return i;
- }
-
- return -1;
-}
-
-/* Worker for range_enc_arfcns(), do not call directly. */
-int _range_enc_arfcns(enum gsm48_range range,
- const int *arfcns, int size, int *out,
- const int index)
-{
- int split_at;
- int i;
-
- /*
- * The below is a GNU extension and we can remove it when
- * we move to a quicksort like in-situ swap with the pivot.
- */
- int arfcns_left[size / 2];
- int arfcns_right[size / 2];
- int l_size;
- int r_size;
- int l_origin;
- int r_origin;
-
- /* Now do the processing */
- split_at = range_enc_find_index(range, arfcns, size);
- if (split_at < 0)
- return -EINVAL;
-
- /* we now know where to split */
- out[index] = 1 + arfcns[split_at];
-
- /* calculate the work that needs to be done for the leafs */
- l_origin = mod(arfcns[split_at] + ((range - 1) / 2) + 1, range);
- r_origin = mod(arfcns[split_at] + 1, range);
- for (i = 0, l_size = 0, r_size = 0; i < size; ++i) {
- if (mod(arfcns[i] - l_origin, range) < range / 2)
- arfcns_left[l_size++] = mod(arfcns[i] - l_origin, range);
- if (mod(arfcns[i] - r_origin, range) < range / 2)
- arfcns_right[r_size++] = mod(arfcns[i] - r_origin, range);
- }
-
- /*
- * Now recurse and we need to make this iterative... but as the
- * tree is balanced the stack will not be too deep.
- */
- if (l_size)
- range_enc_arfcns(range / 2, arfcns_left, l_size,
- out, index + greatest_power_of_2_lesser_or_equal_to(index + 1));
- if (r_size)
- range_enc_arfcns((range - 1) / 2, arfcns_right, r_size,
- out, index + (2 * greatest_power_of_2_lesser_or_equal_to(index + 1)));
- return 0;
-}
-
-/**
- * Range encode the ARFCN list.
- * \param range The range to use.
- * \param arfcns The list of ARFCNs
- * \param size The size of the list of ARFCNs
- * \param out Place to store the W(i) output.
- */
-int range_enc_arfcns(enum gsm48_range range,
- const int *arfcns, int size, int *out,
- const int index)
-{
- if (size <= 0)
- return 0;
-
- if (size == 1) {
- out[index] = 1 + arfcns[0];
- return 0;
- }
-
- return _range_enc_arfcns(range, arfcns, size, out, index);
-}
-
-/*
- * The easiest is to use f0 == arfcns[0]. This means that under certain
- * circumstances we can encode less ARFCNs than possible with an optimal f0.
- *
- * TODO: Solve the optimisation problem and pick f0 so that the max distance
- * is the smallest. Taking into account the modulo operation. I think picking
- * size/2 will be the optimal arfcn.
- */
-/**
- * This implements the range determination as described in GSM 04.08 J4. The
- * result will be a base frequency f0 and the range to use. Note that for range
- * 1024 encoding f0 always refers to ARFCN 0 even if it is not an element of
- * the arfcns list.
- *
- * \param[in] arfcns The input frequencies, they must be sorted, lowest number first
- * \param[in] size The length of the array
- * \param[out] f0 The selected F0 base frequency. It might not be inside the list
- */
-int range_enc_determine_range(const int *arfcns, const int size, int *f0)
-{
- int max = 0;
-
- /* don't dereference arfcns[] array if size is 0 */
- if (size == 0)
- return ARFCN_RANGE_128;
-
- /*
- * Go for the easiest. And pick arfcns[0] == f0.
- */
- max = arfcns[size - 1] - arfcns[0];
- *f0 = arfcns[0];
-
- if (max < 128 && size <= 29)
- return ARFCN_RANGE_128;
- if (max < 256 && size <= 22)
- return ARFCN_RANGE_256;
- if (max < 512 && size <= 18)
- return ARFCN_RANGE_512;
- if (max < 1024 && size <= 17) {
- *f0 = 0;
- return ARFCN_RANGE_1024;
- }
-
- return ARFCN_RANGE_INVALID;
-}
-
-static void write_orig_arfcn(uint8_t *chan_list, int f0)
-{
- chan_list[0] |= (f0 >> 9) & 1;
- chan_list[1] = (f0 >> 1);
- chan_list[2] = (f0 & 1) << 7;
-}
-
-static void write_all_wn(uint8_t *chan_list, int bit_offs,
- int *w, int w_size, int w1_len)
-{
- int octet_offs = 0; /* offset into chan_list */
- int wk_len = w1_len; /* encoding size in bits of w[k] */
- int k; /* 1 based */
- int level = 0; /* tree level, top level = 0 */
- int lvl_left = 1; /* nodes per tree level */
-
- /* W(2^i) to W(2^(i+1)-1) are on w1_len-i bits when present */
-
- for (k = 1; k <= w_size; k++) {
- int wk_left = wk_len;
- DEBUGP(DRR,
- "k=%d, wk_len=%d, offs=%d:%d, level=%d, "
- "lvl_left=%d\n",
- k, wk_len, octet_offs, bit_offs, level, lvl_left);
-
- while (wk_left > 0) {
- int cur_bits = 8 - bit_offs;
- int cur_mask;
- int wk_slice;
-
- if (cur_bits > wk_left)
- cur_bits = wk_left;
-
- cur_mask = ((1 << cur_bits) - 1);
-
- DEBUGP(DRR,
- " wk_left=%d, cur_bits=%d, offs=%d:%d\n",
- wk_left, cur_bits, octet_offs, bit_offs);
-
- /* advance */
- wk_left -= cur_bits;
- bit_offs += cur_bits;
-
- /* right aligned wk data for current out octet */
- wk_slice = (w[k-1] >> wk_left) & cur_mask;
-
- /* cur_bits now contains the number of bits
- * that are to be copied from wk to the chan_list.
- * wk_left is set to the number of bits that must
- * not yet be copied.
- * bit_offs points after the bit area that is going to
- * be overwritten:
- *
- * wk_left
- * |
- * v
- * wk: WWWWWWWWWWW
- * |||||<-- wk_slice, cur_bits=5
- * --WWWWW-
- * ^
- * |
- * bit_offs
- */
-
- DEBUGP(DRR,
- " wk=%02x, slice=%02x/%02x, cl=%02x\n",
- w[k-1], wk_slice, cur_mask, wk_slice << (8 - bit_offs));
-
- chan_list[octet_offs] &= ~(cur_mask << (8 - bit_offs));
- chan_list[octet_offs] |= wk_slice << (8 - bit_offs);
-
- /* adjust output */
- if (bit_offs == 8) {
- bit_offs = 0;
- octet_offs += 1;
- }
- }
-
- /* adjust bit sizes */
- lvl_left -= 1;
- if (!lvl_left) {
- /* completed tree level, advance to next */
- level += 1;
- lvl_left = 1 << level;
- wk_len -= 1;
- }
- }
-}
-
-int range_enc_range128(uint8_t *chan_list, int f0, int *w)
-{
- chan_list[0] = 0x8C;
- write_orig_arfcn(chan_list, f0);
-
- write_all_wn(&chan_list[2], 1, w, 28, 7);
- return 0;
-}
-
-int range_enc_range256(uint8_t *chan_list, int f0, int *w)
-{
- chan_list[0] = 0x8A;
- write_orig_arfcn(chan_list, f0);
-
- write_all_wn(&chan_list[2], 1, w, 21, 8);
- return 0;
-}
-
-int range_enc_range512(uint8_t *chan_list, int f0, int *w)
-{
- chan_list[0] = 0x88;
- write_orig_arfcn(chan_list, f0);
-
- write_all_wn(&chan_list[2], 1, w, 17, 9);
- return 0;
-}
-
-int range_enc_range1024(uint8_t *chan_list, int f0, int f0_included, int *w)
-{
- chan_list[0] = 0x80 | (f0_included << 2);
-
- write_all_wn(&chan_list[0], 6, w, 16, 10);
- return 0;
-}
-
-int range_enc_filter_arfcns(int *arfcns,
- const int size, const int f0, int *f0_included)
-{
- int i, j = 0;
- *f0_included = 0;
-
- for (i = 0; i < size; ++i) {
- /*
- * Appendix J.4 says the following:
- * All frequencies except F(0), minus F(0) + 1.
- * I assume we need to exclude it here.
- */
- if (arfcns[i] == f0) {
- *f0_included = 1;
- continue;
- }
-
- arfcns[j++] = mod(arfcns[i] - (f0 + 1), 1024);
- }
-
- return j;
-}