Portability fix: Adding local partial copy of libosmocore (TODO: minimize it)
diff --git a/lib/decoding/osmocom/core/bits.c b/lib/decoding/osmocom/core/bits.c
new file mode 100644
index 0000000..8837c1f
--- /dev/null
+++ b/lib/decoding/osmocom/core/bits.c
@@ -0,0 +1,311 @@
+/*
+ * (C) 2011 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2011 by Sylvain Munaut <tnt@246tNt.com>
+ *
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program 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.
+ *
+ * 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 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <stdint.h>
+
+#include <osmocom/core/bits.h>
+
+/*! \addtogroup bits
+ * @{
+ * Osmocom bit level support code.
+ *
+ * This module implements the notion of different bit-fields, such as
+ * - unpacked bits (\ref ubit_t), i.e. 1 bit per byte
+ * - packed bits (\ref pbit_t), i.e. 8 bits per byte
+ * - soft bits (\ref sbit_t), 1 bit per byte from -127 to 127
+ *
+ * \file bits.c */
+
+/*! convert unpacked bits to packed bits, return length in bytes
+ * \param[out] out output buffer of packed bits
+ * \param[in] in input buffer of unpacked bits
+ * \param[in] num_bits number of bits
+ */
+int osmo_ubit2pbit(pbit_t *out, const ubit_t *in, unsigned int num_bits)
+{
+ unsigned int i;
+ uint8_t curbyte = 0;
+ pbit_t *outptr = out;
+
+ for (i = 0; i < num_bits; i++) {
+ uint8_t bitnum = 7 - (i % 8);
+
+ curbyte |= (in[i] << bitnum);
+
+ if(i % 8 == 7){
+ *outptr++ = curbyte;
+ curbyte = 0;
+ }
+ }
+ /* we have a non-modulo-8 bitcount */
+ if (i % 8)
+ *outptr++ = curbyte;
+
+ return outptr - out;
+}
+
+/*! Shift unaligned input to octet-aligned output
+ * \param[out] out output buffer, unaligned
+ * \param[in] in input buffer, octet-aligned
+ * \param[in] num_nibbles number of nibbles
+ */
+void osmo_nibble_shift_right(uint8_t *out, const uint8_t *in,
+ unsigned int num_nibbles)
+{
+ unsigned int i, num_whole_bytes = num_nibbles / 2;
+ if (!num_whole_bytes)
+ return;
+
+ /* first byte: upper nibble empty, lower nibble from src */
+ out[0] = (in[0] >> 4);
+
+ /* bytes 1.. */
+ for (i = 1; i < num_whole_bytes; i++)
+ out[i] = ((in[i - 1] & 0xF) << 4) | (in[i] >> 4);
+
+ /* shift the last nibble, in case there's an odd count */
+ i = num_whole_bytes;
+ if (num_nibbles & 1)
+ out[i] = ((in[i - 1] & 0xF) << 4) | (in[i] >> 4);
+ else
+ out[i] = (in[i - 1] & 0xF) << 4;
+}
+
+/*! Shift unaligned input to octet-aligned output
+ * \param[out] out output buffer, octet-aligned
+ * \param[in] in input buffer, unaligned
+ * \param[in] num_nibbles number of nibbles
+ */
+void osmo_nibble_shift_left_unal(uint8_t *out, const uint8_t *in,
+ unsigned int num_nibbles)
+{
+ unsigned int i, num_whole_bytes = num_nibbles / 2;
+ if (!num_whole_bytes)
+ return;
+
+ for (i = 0; i < num_whole_bytes; i++)
+ out[i] = ((in[i] & 0xF) << 4) | (in[i + 1] >> 4);
+
+ /* shift the last nibble, in case there's an odd count */
+ i = num_whole_bytes;
+ if (num_nibbles & 1)
+ out[i] = (in[i] & 0xF) << 4;
+}
+
+/*! convert unpacked bits to soft bits
+ * \param[out] out output buffer of soft bits
+ * \param[in] in input buffer of unpacked bits
+ * \param[in] num_bits number of bits
+ */
+void osmo_ubit2sbit(sbit_t *out, const ubit_t *in, unsigned int num_bits)
+{
+ unsigned int i;
+ for (i = 0; i < num_bits; i++)
+ out[i] = in[i] ? -127 : 127;
+}
+
+/*! convert soft bits to unpacked bits
+ * \param[out] out output buffer of unpacked bits
+ * \param[in] in input buffer of soft bits
+ * \param[in] num_bits number of bits
+ */
+void osmo_sbit2ubit(ubit_t *out, const sbit_t *in, unsigned int num_bits)
+{
+ unsigned int i;
+ for (i = 0; i < num_bits; i++)
+ out[i] = in[i] < 0;
+}
+
+/*! convert packed bits to unpacked bits, return length in bytes
+ * \param[out] out output buffer of unpacked bits
+ * \param[in] in input buffer of packed bits
+ * \param[in] num_bits number of bits
+ * \return number of bytes used in \ref out
+ */
+int osmo_pbit2ubit(ubit_t *out, const pbit_t *in, unsigned int num_bits)
+{
+ unsigned int i;
+ ubit_t *cur = out;
+ ubit_t *limit = out + num_bits;
+
+ for (i = 0; i < (num_bits/8)+1; i++) {
+ pbit_t byte = in[i];
+ *cur++ = (byte >> 7) & 1;
+ if (cur >= limit)
+ break;
+ *cur++ = (byte >> 6) & 1;
+ if (cur >= limit)
+ break;
+ *cur++ = (byte >> 5) & 1;
+ if (cur >= limit)
+ break;
+ *cur++ = (byte >> 4) & 1;
+ if (cur >= limit)
+ break;
+ *cur++ = (byte >> 3) & 1;
+ if (cur >= limit)
+ break;
+ *cur++ = (byte >> 2) & 1;
+ if (cur >= limit)
+ break;
+ *cur++ = (byte >> 1) & 1;
+ if (cur >= limit)
+ break;
+ *cur++ = (byte >> 0) & 1;
+ if (cur >= limit)
+ break;
+ }
+ return cur - out;
+}
+
+/*! convert unpacked bits to packed bits (extended options)
+ * \param[out] out output buffer of packed bits
+ * \param[in] out_ofs offset into output buffer
+ * \param[in] in input buffer of unpacked bits
+ * \param[in] in_ofs offset into input buffer
+ * \param[in] num_bits number of bits
+ * \param[in] lsb_mode Encode bits in LSB orde instead of MSB
+ * \returns length in bytes (max written offset of output buffer + 1)
+ */
+int osmo_ubit2pbit_ext(pbit_t *out, unsigned int out_ofs,
+ const ubit_t *in, unsigned int in_ofs,
+ unsigned int num_bits, int lsb_mode)
+{
+ int i, op, bn;
+ for (i=0; i<num_bits; i++) {
+ op = out_ofs + i;
+ bn = lsb_mode ? (op&7) : (7-(op&7));
+ if (in[in_ofs+i])
+ out[op>>3] |= 1 << bn;
+ else
+ out[op>>3] &= ~(1 << bn);
+ }
+ return ((out_ofs + num_bits - 1) >> 3) + 1;
+}
+
+/*! convert packed bits to unpacked bits (extended options)
+ * \param[out] out output buffer of unpacked bits
+ * \param[in] out_ofs offset into output buffer
+ * \param[in] in input buffer of packed bits
+ * \param[in] in_ofs offset into input buffer
+ * \param[in] num_bits number of bits
+ * \param[in] lsb_mode Encode bits in LSB orde instead of MSB
+ * \returns length in bytes (max written offset of output buffer + 1)
+ */
+int osmo_pbit2ubit_ext(ubit_t *out, unsigned int out_ofs,
+ const pbit_t *in, unsigned int in_ofs,
+ unsigned int num_bits, int lsb_mode)
+{
+ int i, ip, bn;
+ for (i=0; i<num_bits; i++) {
+ ip = in_ofs + i;
+ bn = lsb_mode ? (ip&7) : (7-(ip&7));
+ out[out_ofs+i] = !!(in[ip>>3] & (1<<bn));
+ }
+ return out_ofs + num_bits;
+}
+
+/*! generalized bit reversal function
+ * \param[in] x the 32bit value to be reversed
+ * \param[in] k the type of reversal requested
+ * \returns the reversed 32bit dword
+ *
+ * This function reverses the bit order within a 32bit word. Depending
+ * on "k", it either reverses all bits in a 32bit dword, or the bytes in
+ * the dword, or the bits in each byte of a dword, or simply swaps the
+ * two 16bit words in a dword. See Chapter 7 "Hackers Delight"
+ */
+uint32_t osmo_bit_reversal(uint32_t x, enum osmo_br_mode k)
+{
+ if (k & 1) x = (x & 0x55555555) << 1 | (x & 0xAAAAAAAA) >> 1;
+ if (k & 2) x = (x & 0x33333333) << 2 | (x & 0xCCCCCCCC) >> 2;
+ if (k & 4) x = (x & 0x0F0F0F0F) << 4 | (x & 0xF0F0F0F0) >> 4;
+ if (k & 8) x = (x & 0x00FF00FF) << 8 | (x & 0xFF00FF00) >> 8;
+ if (k & 16) x = (x & 0x0000FFFF) << 16 | (x & 0xFFFF0000) >> 16;
+
+ return x;
+}
+
+/*! reverse the bit-order in each byte of a dword
+ * \param[in] x 32bit input value
+ * \returns 32bit value where bits of each byte have been reversed
+ *
+ * See Chapter 7 "Hackers Delight"
+ */
+uint32_t osmo_revbytebits_32(uint32_t x)
+{
+ x = (x & 0x55555555) << 1 | (x & 0xAAAAAAAA) >> 1;
+ x = (x & 0x33333333) << 2 | (x & 0xCCCCCCCC) >> 2;
+ x = (x & 0x0F0F0F0F) << 4 | (x & 0xF0F0F0F0) >> 4;
+
+ return x;
+}
+
+/*! reverse the bit order in a byte
+ * \param[in] x 8bit input value
+ * \returns 8bit value where bits order has been reversed
+ *
+ * See Chapter 7 "Hackers Delight"
+ */
+uint32_t osmo_revbytebits_8(uint8_t x)
+{
+ x = (x & 0x55) << 1 | (x & 0xAA) >> 1;
+ x = (x & 0x33) << 2 | (x & 0xCC) >> 2;
+ x = (x & 0x0F) << 4 | (x & 0xF0) >> 4;
+
+ return x;
+}
+
+/*! reverse bit-order of each byte in a buffer
+ * \param[in] buf buffer containing bytes to be bit-reversed
+ * \param[in] len length of buffer in bytes
+ *
+ * This function reverses the bits in each byte of the buffer
+ */
+void osmo_revbytebits_buf(uint8_t *buf, int len)
+{
+ unsigned int i;
+ unsigned int unaligned_cnt;
+ int len_remain = len;
+
+ unaligned_cnt = ((unsigned long)buf & 3);
+ for (i = 0; i < unaligned_cnt; i++) {
+ buf[i] = osmo_revbytebits_8(buf[i]);
+ len_remain--;
+ if (len_remain <= 0)
+ return;
+ }
+
+ for (i = unaligned_cnt; i + 3 < len; i += 4) {
+ osmo_store32be(osmo_revbytebits_32(osmo_load32be(buf + i)), buf + i);
+ len_remain -= 4;
+ }
+
+ for (i = len - len_remain; i < len; i++) {
+ buf[i] = osmo_revbytebits_8(buf[i]);
+ len_remain--;
+ }
+}
+
+/*! @} */