trau_frame: New API
The old TRAU frame code in src/trau_frame.c (which is for some strange
reason part of libosmo-abis, and not libosmo-trau!) was introduced more
than a decade ago for the needs of bs11_abis AKA OpenBSC aka OsmoNITB.
It is too constrained to implement TRAU frame parsing in a generic way,
including:
* no way to add support for 8k sub-slots
* no way to handle CRC bits or UFI (i.e. no AMR)
* no real API design, it was just ripped out from OsmoNITB and moved into
a library (even the wrong one)
For those reasons, let's introduce a new API for TRAU frame
encoding/decoding - one that supports all the relevant use cases.
Change-Id: I5cf42e6c445d9224be18503cebc7584b3beba08c
diff --git a/include/Makefile.am b/include/Makefile.am
index 2048520..aa735c5 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -4,4 +4,5 @@
osmocom/abis/ipa_proxy.h osmocom/abis/ipaccess.h osmocom/abis/abis.h \
osmocom/abis/subchan_demux.h osmocom/abis/e1_input.h \
osmocom/abis/lapd.h osmocom/abis/lapd_pcap.h osmocom/trau/osmo_ortp.h \
- osmocom/abis/unixsocket_proto.h
+ osmocom/abis/unixsocket_proto.h \
+ osmocom/trau/trau_frame.h
diff --git a/include/osmocom/trau/trau_frame.h b/include/osmocom/trau/trau_frame.h
new file mode 100644
index 0000000..6784d1f
--- /dev/null
+++ b/include/osmocom/trau/trau_frame.h
@@ -0,0 +1,146 @@
+#pragma once
+/* TRAU frame handling according to GSM TS 48.060 / 48.061 */
+
+/* (C) 2020 by Harald Welte <laforge@gnumonks.org>
+ * All Rights Reserved
+ *
+ * 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 Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <osmocom/core/bits.h>
+#include <osmocom/core/utils.h>
+
+/*! \defgroup trau_frame TRAU frame handling
+ * @{
+ *
+ * \file trau_frame.h
+ */
+
+/*! \brief Maximum number of C-bits in a TRAU frame:
+ * 21 for FR/EFR, 25 for AMR, 15 for OM, 15 for data, 13 for E-data, 21 idle */
+#define MAX_C_BITS 25
+/*! \brief Maximum number of D-bits in a TRAU frame:
+ * 260 for FR/EFR, 256 for AMR, 264 for OM, 288 for E-data */
+#define MAX_D_BITS 288
+/*! \brief Maximum number of T-bits in a TRAU frame for all speech frames */
+#define MAX_T_BITS 4
+/*! \brief Maximum number of S-bits in a TRAU frame for OM */
+#define MAX_S_BITS 6
+/*! \brief Maximum number of M-bits in a TRAU frame for E-data */
+#define MAX_M_BITS 2
+/*! \brief Maximum number of XC-bits in a TRAU frame for 8k */
+#define MAX_XC_BITS 6
+
+/*! 16k sub-slot types: Bits C1..C5 */
+#define TRAU_FT_FR_UP 0x02 /* 0 0 0 1 0 - 3.5.1.1.1 */
+#define TRAU_FT_HR_UP 0x03 /* 0 0 0 1 1 - TS 08.61 5.1.4.1.1 */
+#define TRAU_FT_FR_DOWN 0x1c /* 1 1 1 0 0 - 3.5.1.1.1 */
+#define TRAU_FT_HR_DOWN 0x1d /* 1 1 1 0 1 - TS 08.61 5.1.4.1.1 */
+#define TRAU_FT_EFR 0x1a /* 1 1 0 1 0 - 3.5.1.1.1 */
+#define TRAU_FT_AMR 0x06 /* 0 0 1 1 0 - 3.5.1.2 */
+#define TRAU_FT_OM_UP 0x05 /* 0 0 1 0 1 - 3.5.2 */
+#define TRAU_FT_OM_DOWN 0x1b /* 1 1 0 1 1 - 3.5.2 */
+#define TRAU_FT_DATA_UP 0x08 /* 0 1 0 0 0 - 3.5.3 */
+#define TRAU_FT_DATA_UP_HR 0x09 /* 0 1 0 0 1 - TS 08.61 5.1.4.2 */
+#define TRAU_FT_DATA_DOWN 0x16 /* 1 0 1 1 0 - 3.5.3 */
+#define TRAU_FT_DATA_DOWN_HR 0x17 /* 1 0 1 1 1 - TS 08.61 5.1.4.2 */
+#define TRAU_FT_D145_SYNC 0x14 /* 1 0 1 0 0 - 3.5.3 */
+#define TRAU_FT_EDATA 0x1f /* 1 1 1 1 1 - 3.5.4 */
+#define TRAU_FT_IDLE_UP 0x10 /* 1 0 0 0 0 - 3.5.5 */
+#define TRAU_FT_IDLE_DOWN 0x0e /* 0 1 1 1 0 - 3.5.5 */
+
+/* 8k sub-slot types: Bits C1..C5*/
+#define TRAU8_FT_SPEECH_UP 0x02 /* 0 0 0 1 P - TS 08.61 5.2.4.1.1 */
+#define TRAU8_FT_DATA_UP 0x06 /* 0 0 1 1 P - TS 08.61 5.2.4.1.1 */
+#define TRAU8_FT_OM_UP 0x0a /* 0 1 0 1 P - TS 08.61 5.2.4.1.1 */
+#define TRAU8_FT_SPEECH_DOWN 0x00 /* 0 0 0 U P - TS 08.61 5.2.4.1.2 */
+#define TRAU8_FT_DATA_DOWN 0x04 /* 0 0 1 U P - TS 08.61 5.2.4.1.2 */
+#define TRAU8_FT_OM_DOWN 0x08 /* 0 1 0 U P - TS 08.61 5.2.4.1.2 */
+
+/*********************************************************************************
+ * New API
+ *********************************************************************************/
+
+enum osmo_trau_frame_type {
+ OSMO_TRAU_FT_NONE,
+ OSMO_TRAU16_FT_FR = 1,
+ OSMO_TRAU16_FT_HR,
+ OSMO_TRAU16_FT_EFR,
+ OSMO_TRAU16_FT_AMR,
+ OSMO_TRAU16_FT_OAM,
+ OSMO_TRAU16_FT_DATA,
+ OSMO_TRAU16_FT_EDATA,
+ OSMO_TRAU16_FT_D145_SYNC,
+ OSMO_TRAU16_FT_DATA_HR,
+ OSMO_TRAU16_FT_IDLE,
+
+ OSMO_TRAU8_SPEECH,
+ OSMO_TRAU8_DATA,
+ OSMO_TRAU8_OAM,
+ OSMO_TRAU8_AMR_LOW,
+ OSMO_TRAU8_AMR_6k7,
+ OSMO_TRAU8_AMR_7k4,
+};
+
+extern const struct value_string osmo_trau_frame_type_names[];
+static inline const char *osmo_trau_frame_type_name(enum osmo_trau_frame_type ft) {
+ return get_value_string(osmo_trau_frame_type_names, ft);
+}
+
+enum osmo_trau_frame_direction {
+ OSMO_TRAU_DIR_UL = 0,
+ OSMO_TRAU_DIR_DL = 1,
+};
+
+struct osmo_trau_frame {
+ enum osmo_trau_frame_type type;
+ enum osmo_trau_frame_direction dir;
+
+ ubit_t c_bits[MAX_C_BITS];
+ ubit_t d_bits[MAX_D_BITS];
+ ubit_t t_bits[MAX_T_BITS];
+ ubit_t s_bits[MAX_S_BITS];
+ ubit_t m_bits[MAX_M_BITS];
+ ubit_t ufi; /*!< Unreliable Frame Indication (HR) */
+ ubit_t crc_bits[3]; /*!< CRC0..CRC2 (HR) */
+ ubit_t xc_bits[MAX_XC_BITS]; /*!< XC1..XC6 (8k) */
+};
+
+/*! decode an 8k TRAU frame
+ * \param[out] fr caller-allocated output data structure
+ * \param[in] bits unpacked input bits
+ * \param[in] dir direction
+ * \return 0 on success; negative in case of error */
+int osmo_trau_frame_decode_8k(struct osmo_trau_frame *fr, const ubit_t *bits,
+ enum osmo_trau_frame_direction dir);
+
+/*! decode an 16k TRAU frame
+ * \param[out] fr caller-allocated output data structure
+ * \param[in] bits unpacked input bits
+ * \param[in] dir direction
+ * \return 0 on success; negative in case of error */
+int osmo_trau_frame_decode_16k(struct osmo_trau_frame *fr, const ubit_t *bits,
+ enum osmo_trau_frame_direction dir);
+
+/*! encode a TRAU frame
+ * \param[out] bits caller-allocated memory for unpacked output bits
+ * \param[out] fr input data structure describing TRAU frame
+ * \return number of bits encoded */
+int osmo_trau_frame_encode(ubit_t *bits, size_t n_bits, const struct osmo_trau_frame *fr);
+
+
+/* }@ */
diff --git a/src/Makefile.am b/src/Makefile.am
index 3838a5a..d1743af 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -35,4 +35,5 @@
libosmotrau_la_CFLAGS = $(AM_CFLAGS) $(ORTP_CFLAGS)
libosmotrau_la_LDFLAGS = $(AM_LDFLAGS) -version-info $(TRAU_LIBVERSION)
libosmotrau_la_LIBADD = $(COMMONLIBS) $(ORTP_LIBS)
-libosmotrau_la_SOURCES = trau/osmo_ortp.c
+libosmotrau_la_SOURCES = trau/osmo_ortp.c \
+ trau/trau_frame.c
diff --git a/src/trau/trau_frame.c b/src/trau/trau_frame.c
new file mode 100644
index 0000000..a57d642
--- /dev/null
+++ b/src/trau/trau_frame.c
@@ -0,0 +1,1364 @@
+/* New (2020) TRAU frame handling according to GSM TS 48.060 + 48.061 */
+
+/* (C) 2020 by Harald Welte <laforge@gnumonks.org>
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: AGPL-3.0+
+ *
+ * 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 "internal.h"
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+
+#include <osmocom/trau/trau_frame.h>
+#include <osmocom/core/logging.h>
+
+/*! \addtogroup trau_frame
+ * @{
+ *
+ * \file trau_frame.c
+ */
+
+static uint32_t get_bits(const ubit_t *bitbuf, int offset, int num)
+{
+ int i;
+ uint32_t ret = 0;
+
+ for (i = offset; i < offset + num; i++) {
+ ret = ret << 1;
+ if (bitbuf[i])
+ ret |= 1;
+ }
+ return ret;
+}
+
+const struct value_string osmo_trau_frame_type_names[] = {
+ { OSMO_TRAU_FT_NONE, "NONE" },
+ { OSMO_TRAU16_FT_FR, "FR" },
+ { OSMO_TRAU16_FT_HR, "HR" },
+ { OSMO_TRAU16_FT_EFR, "EFR" },
+ { OSMO_TRAU16_FT_AMR, "AMR" },
+ { OSMO_TRAU16_FT_OAM, "OAM" },
+ { OSMO_TRAU16_FT_DATA, "DATA" },
+ { OSMO_TRAU16_FT_EDATA, "EDATA" },
+ { OSMO_TRAU16_FT_D145_SYNC, "D145_SYNC" },
+ { OSMO_TRAU16_FT_DATA_HR, "DATA_HR" },
+ { OSMO_TRAU16_FT_IDLE, "IDLE" },
+ { OSMO_TRAU8_SPEECH, "8SPEECH" },
+ { OSMO_TRAU8_DATA, "8DATA" },
+ { OSMO_TRAU8_OAM, "8OAM" },
+ { OSMO_TRAU8_AMR_LOW, "8AMR_LOW" },
+ { OSMO_TRAU8_AMR_6k7, "8AMR_6k7" },
+ { OSMO_TRAU8_AMR_7k4, "8AMR_7k4" },
+ { 0, NULL }
+};
+
+/*********************************************************************************
+ * New API; introduced in 2020 for use by osmo-mgw
+ *********************************************************************************/
+
+/* 16k sub-slots */
+static const ubit_t ft_fr_up_bits[5] = { 0, 0, 0, 1, 0 };
+static const ubit_t ft_fr_down_bits[5] = { 1, 1, 1, 0, 0 };
+static const ubit_t ft_data_up_bits[5] = { 0, 1, 0, 0, 0 };
+static const ubit_t ft_data_down_bits[5] = { 1, 0, 1, 1, 0 };
+static const ubit_t ft_idle_up_bits[5] = { 1, 0, 0, 0, 0 };
+static const ubit_t ft_idle_down_bits[5] = { 0, 1, 1, 1, 0 };
+static const ubit_t ft_efr_bits[5] = { 1, 1, 0, 1, 0 };
+static const ubit_t ft_amr_bits[5] = { 0, 0, 1, 1, 0 };
+static const ubit_t ft_oam_up_bits[5] = { 0, 0, 1, 0, 1 };
+static const ubit_t ft_oam_down_bits[5] = { 1, 1, 0, 1, 1 };
+static const ubit_t ft_d145s_bits[5] = { 1, 0, 1, 0, 0 };
+static const ubit_t ft_edata_bits[5] = { 1, 1, 1, 1, 1 };
+
+/* 8k sub-slots */
+static const ubit_t ft_hr_up_bits[5] = { 0, 0, 0, 1, 1 };
+static const ubit_t ft_hr_down_bits[5] = { 1, 1, 1, 0, 1 };
+static const ubit_t ft_data_hr_up_bits[5] = { 0, 1, 0, 0, 1 };
+static const ubit_t ft_data_hr_down_bits[5] = { 1, 0, 1, 1, 1 };
+
+
+/* generate the sync pattern described in TS 08.60 4.8.1 */
+static void encode_sync16(ubit_t *trau_bits)
+{
+ int i;
+
+ /* 16 '0' bits in header */
+ memset(trau_bits, 0, 16);
+ /* '1'-bit in regular intervals */
+ for (i = 16; i < 40*8; i += 16)
+ trau_bits[i] = 1;
+}
+
+#define T16_500us 8 /* 500 us = 8 bits */
+#define T16_250us 4 /* 250 us = 4 bits */
+
+/* How many 16k bits to delay / advance (TS 48.060 Section 5.5.1.1.1) */
+static int fr_efr_alignment_bitcount(uint8_t c6_11)
+{
+ if (c6_11 <= 0x27)
+ return c6_11 * T16_500us; /* delay frame N x 500us */
+ else if (c6_11 == 0x3e)
+ return T16_250us; /* delay frame 250us */
+ else if (c6_11 == 0x3f)
+ return -T16_250us; /* advance frame 250us */
+ else
+ return 0;
+}
+
+/* TS 08.60 Section 3.1.1 */
+static int encode16_fr(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ const ubit_t *cbits5;
+ int i;
+ int d_idx = 0;
+
+ switch (fr->type) {
+ case OSMO_TRAU16_FT_IDLE:
+ if (fr->dir == OSMO_TRAU_DIR_UL)
+ cbits5 = ft_idle_up_bits;
+ else
+ cbits5 = ft_idle_down_bits;
+ break;
+ case OSMO_TRAU16_FT_FR:
+ if (fr->dir == OSMO_TRAU_DIR_UL)
+ cbits5 = ft_fr_up_bits;
+ else
+ cbits5 = ft_fr_down_bits;
+ break;
+ case OSMO_TRAU16_FT_EFR:
+ cbits5 = ft_efr_bits;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ encode_sync16(trau_bits);
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 17, cbits5 + 0, 5);
+ /* C6 .. C15 */
+ memcpy(trau_bits + 17 + 5, fr->c_bits + 5, 15 - 5);
+ /* D1 .. D255 */
+ for (i = 32; i < 304; i += 16) {
+ trau_bits[i] = 1;
+ memcpy(trau_bits + i + 1, fr->d_bits + d_idx, 15);
+ d_idx += 15;
+ }
+ /* D256 .. D260 */
+ trau_bits[304] = 1;
+ memcpy(trau_bits + 305, fr->d_bits + d_idx, 5);
+ /* C16 .. C21 */
+ memcpy(trau_bits + 310, fr->c_bits + 15, 6);
+
+ /* T1 .. T4 */
+ memcpy(trau_bits + 316, fr->t_bits+0, 4);
+
+ /* handle timing adjustment */
+ if (fr->dir == OSMO_TRAU_DIR_DL) {
+ uint8_t cbits6_11 = get_bits(fr->c_bits, 5, 6);
+ int ta_bits = fr_efr_alignment_bitcount(cbits6_11);
+ if (ta_bits > 0) {
+ memset(trau_bits+320, 1, ta_bits);
+ return 320 + ta_bits;
+ } else if (ta_bits < 0)
+ return 320 - ta_bits;
+ }
+ return 40 * 8;
+}
+
+/* TS 08.60 Section 3.1.1 */
+static int decode16_fr(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i;
+ int d_idx = 0;
+
+ /* C1 .. C15 */
+ memcpy(fr->c_bits + 0, trau_bits + 17, 15);
+ /* C16 .. C21 */
+ memcpy(fr->c_bits + 15, trau_bits + 310, 6);
+ /* T1 .. T4 */
+ memcpy(fr->t_bits + 0, trau_bits + 316, 4);
+ /* D1 .. D255 */
+ for (i = 32; i < 304; i+= 16) {
+ memcpy(fr->d_bits + d_idx, trau_bits + i + 1, 15);
+ d_idx += 15;
+ }
+ /* D256 .. D260 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 305, 5);
+
+ return 0;
+}
+
+/* TS 08.60 Section 3.1.2 */
+static int encode16_amr(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ const ubit_t *cbits5 = ft_amr_bits;
+ int i, d_idx;
+
+ encode_sync16(trau_bits);
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 17, cbits5 + 0, 5);
+ /* C6 .. C15 */
+ memcpy(trau_bits + 17 + 5, fr->c_bits + 5, 15 - 5);
+
+ trau_bits[32] = 1;
+ /* C16 .. C25 */
+ memcpy(trau_bits + 33, fr->c_bits + 15, 10);
+ /* D1 .. D5 */
+ memcpy(trau_bits + 43, fr->d_bits + 0, 5);
+
+ /* D6 .. D256 */
+ for (i = 48, d_idx = 5; i <= 315; i += 16, d_idx += 15) {
+ trau_bits[i] = 1;
+ memcpy(trau_bits + i + 1, fr->d_bits + d_idx, 15);
+ }
+
+ /* T1 .. T4 */
+ memcpy(trau_bits + 316, fr->t_bits + 0, 4);
+
+ /* handle timing adjustment */
+ if (fr->dir == OSMO_TRAU_DIR_DL) {
+ uint8_t cbits6_11 = get_bits(fr->c_bits, 5, 6);
+ int ta_bits = fr_efr_alignment_bitcount(cbits6_11);
+ if (ta_bits > 0) {
+ memset(trau_bits+320, 1, ta_bits);
+ return 320 + ta_bits;
+ } else if (ta_bits < 0)
+ return 320 - ta_bits;
+ }
+ /* FIXME: handle TAE (Timing Alignment Extension) */
+ return 40 * 8;
+}
+
+/* TS 08.60 Section 3.1.2 */
+static int decode16_amr(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i;
+ int d_idx = 0;
+
+ /* C1 .. C15 */
+ memcpy(fr->c_bits + 0, trau_bits + 17, 15);
+ /* C16 .. C25 */
+ memcpy(fr->c_bits + 15, trau_bits + 33, 10);
+ /* T1 .. T4 */
+ memcpy(fr->t_bits + 0, trau_bits + 316, 4);
+ /* D1 .. D5 */
+ memcpy(fr->d_bits, trau_bits + 43, 5);
+ d_idx += 5;
+ /* D6 .. D245 */
+ for (i = 48; i < 304; i += 16) {
+ memcpy(fr->d_bits + d_idx, trau_bits + i + 1, 15);
+ d_idx += 15;
+ }
+ /* D246 .. D256 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 305, 11);
+
+ return 0;
+}
+
+/* TS 08.60 Section 3.2 */
+static int encode16_oam(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ const ubit_t *cbits5;
+ int i, d_idx;
+
+ if (fr->dir == OSMO_TRAU_DIR_UL)
+ cbits5 = ft_oam_up_bits;
+ else
+ cbits5 = ft_oam_down_bits;
+
+ encode_sync16(trau_bits);
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 17, cbits5, 5);
+ /* C6 .. C15 */
+ memcpy(trau_bits + 17 + 5, fr->c_bits, 15 - 5);
+
+ /* D1 .. D255 */
+ for (i = 32, d_idx = 0; i < 304; i += 16, d_idx += 15) {
+ trau_bits[i] = 1;
+ memcpy(trau_bits + i + 1, fr->d_bits + d_idx, 15);
+ }
+ /* D256 .. D264 */
+ memcpy(trau_bits + 305, fr->d_bits + 256, 9);
+
+ /* S1 .. S6 */
+ memcpy(trau_bits + 314, fr->s_bits, 6);
+
+ return 40 * 8;
+}
+
+/* TS 08.60 Section 3.2 */
+static int decode16_oam(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx;
+
+ /* C1 .. C15 */
+ memcpy(fr->c_bits + 0, trau_bits + 17, 15);
+
+ /* D1 .. D255 */
+ for (i = 33, d_idx = 0; i < 312; i+= 16, d_idx += 15)
+ memcpy(fr->d_bits + d_idx, trau_bits + i + 1, 15);
+ /* D256 .. D264 */
+ memcpy(fr->d_bits+d_idx, trau_bits + 305, 9);
+
+ /* S1 .. S6 */
+ memcpy(fr->s_bits, trau_bits + 314, 6);
+
+ return 0;
+}
+
+/* TS 08.61 Section 5.1.1.1 */
+static int encode16_hr(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ int d_idx = 0;
+ const ubit_t *cbits5;
+
+ if (fr->dir == OSMO_TRAU_DIR_UL)
+ cbits5 = ft_hr_up_bits;
+ else
+ cbits5 = ft_hr_down_bits;
+
+ encode_sync16(trau_bits);
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 17, cbits5, 5);
+ /* C6 .. C15 */
+ memcpy(trau_bits + 17 + 5, fr->c_bits + 5, 10);
+
+ /* UFI */
+ trau_bits[33] = fr->ufi;
+
+ /* D1 .. D14 */
+ memcpy(trau_bits + 4 * 8 + 2, fr->d_bits+d_idx, 14); d_idx += 14;
+ /* D15 .. D29 */
+ memcpy(trau_bits + 6 * 8 + 1, fr->d_bits+d_idx, 15); d_idx += 15;
+ /* D30 .. D44 */
+ memcpy(trau_bits + 8 * 8 + 1, fr->d_bits+d_idx, 15); d_idx += 15;
+ /* CRC */
+ memcpy(trau_bits + 10 * 8 + 1, fr->crc_bits, 3);
+ /* D45 .. D56 */
+ memcpy(trau_bits + 10 * 8 + 4, fr->d_bits+d_idx, 12); d_idx += 12;
+ /* D57 .. D71 */
+ memcpy(trau_bits + 12 * 8 + 1, fr->d_bits+d_idx, 15); d_idx += 15;
+ /* D72 .. D86 */
+ memcpy(trau_bits + 14 * 8 + 1, fr->d_bits+d_idx, 15); d_idx += 15;
+ /* D87 .. D101 */
+ memcpy(trau_bits + 16 * 8 + 1, fr->d_bits+d_idx, 15); d_idx += 15;
+ /* D102 .. D112 */
+ memcpy(trau_bits + 18 * 8 + 1, fr->d_bits+d_idx, 11); d_idx += 11;
+
+ memset(trau_bits + 19 * 8 + 4, 0x01, 4 + 18 * 8 + 6);
+ /* C16 .. C21 */
+ memcpy(trau_bits + 38 * 8 + 6, fr->c_bits + 15, 6);
+
+ /* T1 .. T4 */
+ memcpy(trau_bits + 39 * 8 + 4, fr->t_bits, 4);
+
+ /* handle timing adjustment */
+ if (fr->dir == OSMO_TRAU_DIR_DL) {
+ uint8_t cbits6_11 = get_bits(fr->c_bits, 5, 6);
+ int ta_bits = fr_efr_alignment_bitcount(cbits6_11);
+ if (ta_bits > 0) {
+ memset(trau_bits+320, 1, ta_bits);
+ return 320 + ta_bits;
+ } else if (ta_bits < 0)
+ return 320 - ta_bits;
+ }
+ return 40 * 8;
+}
+
+/* TS 08.61 Section 5.1.1.1 */
+static int decode16_hr(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int d_idx = 0;
+
+ /* C1 .. C15 */
+ memcpy(fr->c_bits + 0, trau_bits + 17, 15);
+ /* C16 .. C21 */
+ memcpy(fr->c_bits + 15, trau_bits + 38 * 8 + 6, 6);
+ /* T1 .. T4 */
+ memcpy(fr->t_bits + 0, trau_bits + 39 * 8 + 4, 4);
+
+ /* UFI */
+ fr->ufi = trau_bits[33];
+ /* D1 .. D14 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 4 * 8 + 2, 14); d_idx += 14;
+ /* D15 .. D29 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 6 * 8 + 1, 15); d_idx += 15;
+ /* D30 .. D44 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 8 * 8 + 1, 15); d_idx += 15;
+ /* CRC0..2 */
+ memcpy(fr->crc_bits, trau_bits + 10 * 8 + 1, 3);
+ /* D45 .. D56 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 10 * 8 + 4, 12); d_idx += 12;
+ /* D57 .. D71 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 12 * 8 + 1, 15); d_idx += 15;
+ /* D72 .. D86 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 14 * 8 + 1, 15); d_idx += 15;
+ /* D87 .. D101 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 16 * 8 + 1, 15); d_idx += 15;
+ /* D102 .. D112 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 18 * 8 + 1, 11); d_idx += 11;
+
+ return 0;
+}
+
+static struct osmo_trau_frame fr_idle_frame = {
+ .type = OSMO_TRAU16_FT_IDLE,
+ .dir = OSMO_TRAU_DIR_DL,
+ .t_bits = { 1, 1, 1, 1 },
+};
+#define TRAU_FRAME_BITS (40*8)
+static ubit_t encoded_idle_frame[TRAU_FRAME_BITS];
+static int dbits_initted = 0;
+
+/*! \brief return pointer to global buffer containing a TRAU idle frame */
+static ubit_t *trau_idle_frame(void)
+{
+ /* only initialize during the first call */
+ if (!dbits_initted) {
+ /* set all D-bits to 1 */
+ memset(&fr_idle_frame.d_bits, 0x01, 260);
+
+ memset(&fr_idle_frame.c_bits, 0x01, 25); /* spare are set to 1 */
+ /* set Downlink Idle Speech Frame pattern */
+ fr_idle_frame.c_bits[0] = 0; /* C1 */
+ fr_idle_frame.c_bits[1] = 1; /* C2 */
+ fr_idle_frame.c_bits[2] = 1; /* C3 */
+ fr_idle_frame.c_bits[3] = 1; /* C4 */
+ fr_idle_frame.c_bits[4] = 0; /* C5 */
+ /* set no Time Alignment pattern */
+ fr_idle_frame.c_bits[5] = 0; /* C6 */
+ fr_idle_frame.c_bits[6] = 0; /* C7 */
+ fr_idle_frame.c_bits[7] = 0; /* C8 */
+ fr_idle_frame.c_bits[8] = 0; /* C9 */
+ fr_idle_frame.c_bits[9] = 0; /* C10 */
+ fr_idle_frame.c_bits[10] = 0; /* C11 */
+ /* already set to 1, but maybe we need to modify it in the future */
+ fr_idle_frame.c_bits[11] = 1; /* C12 (UFE), good frame */
+ fr_idle_frame.c_bits[15] = 1; /* C16 (SP), no DTX */
+
+ encode16_fr(encoded_idle_frame, &fr_idle_frame);
+ dbits_initted = 1; /* set it to 1 to not call it again */
+ }
+ return encoded_idle_frame;
+}
+
+/* TS 08.60 Section 3.4 */
+static int encode16_idle(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ memcpy(trau_bits, trau_idle_frame(), 40*8);
+ return 40 * 8;
+}
+
+/* TS 08.60 Section 3.3.1 */
+static int decode16_data(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx = 0;
+
+ /* C1 .. C15 */
+ memcpy(fr->c_bits + 0, trau_bits + 17, 15);
+
+ /* D1 .. D63 */
+ for (i = 0; i < 9; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + (4 + i) * 8 + 1, 7);
+ d_idx += 7;
+ }
+ /* D64 .. D126 */
+ for (i = 0; i < 9; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + (13 + i) * 8 + 1, 7);
+ d_idx += 7;
+ }
+
+ /* D127 .. D189 */
+ for (i = 0; i < 9; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + (22 + i) * 8 + 1, 7);
+ d_idx += 7;
+ }
+
+ /* D190 .. D252 */
+ for (i = 0; i < 9; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + (31 + i) * 8 + 1, 7);
+ d_idx += 7;
+ }
+
+ return 0;
+}
+
+/* TS 08.60 Section 3.3.1 */
+static int encode16_data(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ const ubit_t *cbits5;
+ int i, d_idx = 0;
+
+ if (fr->dir == OSMO_TRAU_DIR_UL)
+ cbits5 = ft_data_up_bits;
+ else
+ cbits5 = ft_data_down_bits;
+
+ encode_sync16(trau_bits);
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 17, cbits5, 5);
+ /* C6 .. C15 */
+ memcpy(trau_bits + 17 + 5, fr->c_bits + 5, 15 - 5);
+
+ /* D1 .. D63 */
+ for (i = 0; i < 9; i++) {
+ unsigned int offset = (4 + i) * 8;
+ trau_bits[offset] = 1;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+
+ /* D64 .. D126 */
+ for (i = 0; i < 9; i++) {
+ unsigned int offset = (13 + i) * 8;
+ trau_bits[offset] = 1;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+
+ /* D127 .. D189 */
+ for (i = 0; i < 9; i++) {
+ unsigned int offset = (22 + i) * 8;
+ trau_bits[offset] = 1;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+
+ /* D190 .. D252 */
+ for (i = 0; i < 9; i++) {
+ unsigned int offset = (31 + i) * 8;
+ trau_bits[offset] = 1;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+
+ return 40 * 8;
+}
+
+/* TS 08.60 3.3.2 */
+static int decode16_edata(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ /* C1 .. C13 */
+ memcpy(fr->c_bits, trau_bits + 17, 13);
+
+ /* M1 .. M2 */
+ memcpy(fr->m_bits, trau_bits + 30, 2);
+
+ /* D1 .. D288 */
+ memcpy(fr->d_bits, trau_bits + 4 * 8, 288);
+
+ return 0;
+}
+
+/* TS 08.60 Section 3.3.2 */
+static int encode16_edata(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ const ubit_t *cbits5;
+
+ if (fr->type == OSMO_TRAU16_FT_D145_SYNC)
+ cbits5 = ft_d145s_bits;
+ else
+ cbits5 = ft_edata_bits;
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 17, cbits5, 5);
+
+ /* C6 .. C13 */
+ memcpy(trau_bits + 17 + 5, fr->c_bits + 5, 8);
+
+ /* M1 .. M2 */
+ memcpy(trau_bits + 30, fr->m_bits, 2);
+
+ /* D1 .. D288 */
+ memcpy(trau_bits + 4 * 8, fr->d_bits, 288);
+
+ return 40 * 8;
+}
+
+/* TS 08.61 Section 5.1.2 */
+static int decode16_data_hr(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx = 0;
+
+ /* C1 .. C15 */
+ memcpy(fr->c_bits+0, trau_bits + 17, 15);
+
+ /* D1 .. D63 */
+ for (i = 0; i < 9; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + (4 + i) * 8 + 1, 7);
+ d_idx += 7;
+ }
+
+ /* D'1 .. D'63 (mapped to D64..D127) */
+ for (i = 0; i < 9; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + (22 + i) * 8 + 1, 7);
+ d_idx += 7;
+ }
+
+ return 0;
+}
+
+/* TS 08.61 Section 5.1.2 */
+static int encode16_data_hr(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ const ubit_t *cbits5;
+ int i, d_idx = 0;
+
+ if (fr->dir == OSMO_TRAU_DIR_UL)
+ cbits5 = ft_data_hr_up_bits;
+ else
+ cbits5 = ft_data_hr_down_bits;
+
+ encode_sync16(trau_bits);
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 17, cbits5, 5);
+ /* C6 .. C15 */
+ memcpy(trau_bits + 17 + 5, fr->c_bits + 5, 15 - 5);
+
+ /* D1 .. D63 */
+ for (i = 4; i < 4 + 9; i++) {
+ unsigned int offset = i * 8;
+ trau_bits[offset] = 1;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+
+ memset(trau_bits + 13*8, 1, 9*8);
+
+ /* D'1 .. D'63 (mapped to D64..D127) */
+ for (i = 22; i < 22 + 9; i++) {
+ unsigned int offset = i * 8;
+ trau_bits[offset] = 1;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+
+ memset(trau_bits + 31*8, 1, 9*8);
+
+ return 40 * 8;
+}
+
+/* TS 08.61 Section 5.2.1.1 */
+static int decode8_hr(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx = 0;
+
+ /* C1 .. C5 */
+ memcpy(fr->c_bits, trau_bits + 9, 5);
+ /* XC1 .. XC2 */
+ memcpy(fr->xc_bits, trau_bits + 8 + 6, 2);
+ /* XC3 .. XC6 */
+ memcpy(fr->xc_bits + 2, trau_bits + 2 * 8 + 2, 4);
+ /* D1 .. D2 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 2 * 8 + 6, 2);
+ d_idx += 2;
+
+ /* D1 .. D44 */
+ for (i = 3; i < 3 + 6; i++) {
+ int offset = i * 8;
+ memcpy(fr->d_bits + d_idx, trau_bits + offset + 1, 7);
+ d_idx += 7;
+ }
+
+ /* CRC0 .. CRC2 */
+ fr->crc_bits[2] = trau_bits[82];
+ fr->crc_bits[1] = trau_bits[83];
+ fr->crc_bits[0] = trau_bits[84];
+
+ /* D45 .. D48 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 85, 4);
+
+ /* D49 .. D111 */
+ for (i = 10; i < 10 + 10; i++) {
+ int offset = i * 8;
+ memcpy(fr->d_bits + d_idx, trau_bits + offset + 1, 7);
+ d_idx += 7;
+ }
+ /* D112 */
+ fr->d_bits[d_idx++] = trau_bits[19 * 8 + 1];
+
+ /* C6 .. C9 */
+ memcpy(fr->c_bits + 5, trau_bits + 19 * 8 + 2, 4);
+
+ /* T1 .. T2 */
+ fr->t_bits[0] = trau_bits[19 * 8 + 6];
+ fr->t_bits[1] = trau_bits[19 * 8 + 7];
+
+ return 0;
+}
+
+/* compute the odd parity bit of the given input bit sequence */
+static ubit_t compute_odd_parity(const ubit_t *in, unsigned int num_bits)
+{
+ int i;
+ unsigned int sum = 0;
+
+ for (i = 0; i < num_bits; i++) {
+ if (in[i])
+ sum++;
+ }
+
+ if (sum % 1)
+ return 0;
+ else
+ return 1;
+}
+
+/* TS 08.61 Section 5.2.1.1 */
+static int encode8_hr(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ int i, d_idx = 0;
+
+ /* sync pattern */
+ memset(trau_bits, 0, 8);
+ trau_bits[8] = 1;
+ trau_bits[16] = 0;
+ trau_bits[17] = 1;
+ for (i = 3; i < 20; i++)
+ trau_bits[i * 8] = 1;
+
+ /* C1 .. C5 */
+ ubit_t *cbits_out = trau_bits + 1 * 8 + 1;
+ if (fr->dir == OSMO_TRAU_DIR_UL) {
+ cbits_out[0] = 0;
+ cbits_out[1] = 0;
+ cbits_out[2] = 0;
+ cbits_out[3] = 1;
+ cbits_out[4] = 1;
+ } else {
+ cbits_out[0] = 0;
+ cbits_out[1] = 0;
+ cbits_out[2] = 0;
+ cbits_out[3] = fr->c_bits[3];
+ cbits_out[4] = compute_odd_parity(cbits_out, 4);
+ }
+
+ /* XC1 .. XC2 */
+ memcpy(trau_bits + 1 * 8 + 6, fr->xc_bits, 2);
+ /* XC3 .. XC6 */
+ memcpy(trau_bits + 2 * 8 + 2, fr->xc_bits, 4);
+ /* D1 .. D2 */
+ memcpy(trau_bits + 2 * 8 + 6, fr->d_bits, 2);
+ d_idx += 2;
+
+ /* D1 .. D44 */
+ for (i = 3; i < 3 + 6; i++) {
+ int offset = i * 8;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ };
+
+ /* CRC0 .. CRC2 */
+ trau_bits[82] = fr->crc_bits[2];
+ trau_bits[83] = fr->crc_bits[1];
+ trau_bits[84] = fr->crc_bits[0];
+
+ /* D49 .. D111 */
+ for (i = 10; i < 10 + 10; i++) {
+ int offset = i * 8;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+ /* D112 */
+ trau_bits[19 * 8 + 1] = fr->d_bits[d_idx++];
+
+ /* C6 .. C9 */
+ memcpy(trau_bits + 19 * 8 + 2, fr->c_bits + 5, 4);
+
+ /* FIXME: handle timing adjustment */
+ /* T1 .. T2 */
+ trau_bits[19 * 8 + 6] = fr->t_bits[0];
+ trau_bits[19 * 8 + 7] = fr->t_bits[1];
+
+ return 20 * 8;
+}
+
+/* TS 08.61 Section 5.2.1.2.1 */
+static int decode8_amr_low(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx = 0;
+
+ /* D1 .. D7 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 1 * 8 + 1, 7);
+ d_idx += 7;
+ /* C1 .. C5 */
+ memcpy(fr->c_bits, trau_bits + 2 * 8 + 1, 5);
+ /* D8 .. D9 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 2 * 8 + 6, 2);
+ d_idx += 2;
+ /* D10 .. D15 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 3 * 8 + 2, 6);
+ d_idx += 6;
+ /* D16 .. D120 */
+ for (i = 4; i < 19; i++) {
+ int offset = i * 8;
+ memcpy(fr->d_bits + d_idx, trau_bits + offset + 1, 7);
+ d_idx += 7;
+ }
+ /* D121 .. D126 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 19 * 8 + 1, 6);
+ d_idx += 6;
+
+ /* T1 */
+ fr->t_bits[0] = trau_bits[19 * 8 + 7];
+
+ return 0;
+}
+
+/* TS 08.61 Section 5.2.1.2.1 */
+static int encode8_amr_low(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ int i, d_idx = 0;
+
+ /* sync pattern */
+ memset(trau_bits, 0, 8);
+ trau_bits[8] = 1;
+ trau_bits[16] = 1;
+ trau_bits[24] = 0;
+ trau_bits[25] = 1;
+ for (i = 4; i < 20; i++)
+ trau_bits[i * 8] = 1;
+
+ /* D1 .. D7 */
+ memcpy(trau_bits + 1 * 8 + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ /* C1 .. C5 */
+ memcpy(trau_bits + 2 * 8 + 1, fr->c_bits, 5);
+ /* D8 .. D9 */
+ memcpy(trau_bits + 2 * 8 + 6, fr->d_bits + d_idx, 2);
+ d_idx += 2;
+ /* D10 .. D15 */
+ memcpy(trau_bits + 3 * 8 + 2, fr->d_bits + d_idx, 6);
+ d_idx += 6;
+ /* D16 .. D120 */
+ for (i = 4; i < 19; i++) {
+ int offset = i * 8;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+ /* D121 .. D126 */
+ memcpy(trau_bits + 19 * 8 + 1, fr->d_bits + d_idx, 6);
+ d_idx += 6;
+
+ /* T1 */
+ trau_bits[19 * 8 + 7] = fr->t_bits[0];
+
+ return 20 * 8;
+}
+
+/* TS 08.61 Section 5.2.1.2.2 */
+static int decode8_amr_67(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx = 0;
+
+ /* D1 .. D7 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 1 * 8 + 1, 7);
+ d_idx += 7;
+ /* C1 .. C3 */
+ memcpy(fr->c_bits, trau_bits + 2 * 8 + 1, 3);
+ /* D8 .. D11 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 2 * 8 + 4, 4);
+ d_idx += 4;
+ /* D12 .. D39 */
+ for (i = 3; i < 7; i++) {
+ int offset = i * 8;
+ memcpy(fr->d_bits + d_idx, trau_bits + offset + 2, 7);
+ d_idx += 7;
+ }
+
+ /* D40 .. D137 */
+ for (i = 7; i < 20; i+= 2) {
+ int offset = i * 8;
+ memcpy(fr->d_bits + d_idx, trau_bits + offset + 1, 15);
+ d_idx += 15;
+ }
+
+ return 0;
+}
+
+/* TS 08.61 Section 5.1.2.2 */
+static int encode8_amr_67(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ int i, d_idx = 0;
+
+ /* sync pattern */
+ memset(trau_bits, 0, 8);
+ trau_bits[1 * 8] = 1;
+ trau_bits[2 * 8] = 1;
+ trau_bits[3 * 8] = 1;
+ trau_bits[4 * 8] = 1;
+ trau_bits[5 * 8] = 0;
+ for (i = 5; i < 20; i += 2)
+ trau_bits[i * 8] = 1;
+
+ /* D1 .. D7 */
+ memcpy(trau_bits + 1 * 8 + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ /* C1 .. C3 */
+ memcpy(trau_bits + 2 * 8 + 1, fr->c_bits, 3);
+ /* D8 .. D11 */
+ memcpy(trau_bits + 2 * 8 + 4, fr->d_bits + d_idx, 4);
+ d_idx += 4;
+ /* D12 .. D39 */
+ for (i = 3; i < 7; i++) {
+ int offset = i * 8;
+ memcpy(trau_bits + offset + 2, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+
+ /* D40 .. D137 */
+ for (i = 7; i < 20; i+= 2) {
+ int offset = i * 8;
+ memcpy(trau_bits + offset + 1, fr->d_bits + d_idx, 15);
+ d_idx += 15;
+ }
+
+ return 20 * 8;
+}
+
+/* TS 08.61 Section 5.1.2.3 */
+static int decode8_amr_74(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int d_idx = 0;
+
+ /* D1 .. D5 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 3, 5);
+ d_idx += 5;
+ /* D6 .. D12 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 1 * 8 + 1, 7);
+ d_idx += 7;
+ /* C1.. C3 */
+ memcpy(fr->c_bits, trau_bits + 2 * 8 + 1, 3);
+ /* D13 .. D16 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 2 * 8 + 4, 4);
+ d_idx += 4;
+ /* D17 .. D23 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 3 * 8 + 1, 7);
+ d_idx += 7;
+ /* D24 .. D151 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 4 * 8, 16 * 8);
+
+ return 0;
+}
+
+/* TS 08.61 Section 5.1.2.3 */
+static int encode8_amr_74(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ int d_idx = 0;
+
+ /* sync pattern */
+ trau_bits[0] = 0;
+ trau_bits[1] = 0;
+ trau_bits[2] = 1;
+ trau_bits[1*8] = 0;
+ trau_bits[2*8] = 1;
+ trau_bits[3*8] = 0;
+
+ /* D1 .. D5 */
+ memcpy(trau_bits + 3, fr->d_bits + d_idx, 5);
+ d_idx += 5;
+ /* D6 .. D12 */
+ memcpy(trau_bits + 1 * 8 + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ /* C1.. C3 */
+ memcpy(trau_bits + 2 * 8 + 1, fr->c_bits, 3);
+ /* D13 .. D16 */
+ memcpy(trau_bits + 2 * 8 + 4, fr->d_bits + d_idx, 4);
+ d_idx += 4;
+ /* D17 .. D23 */
+ memcpy(trau_bits + 3 * 8 + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ /* D24 .. D151 */
+ memcpy(trau_bits + 4 * 8, fr->d_bits + d_idx, 16 * 8);
+
+ return 20 * 8;
+}
+
+/* TS 08.61 Section 5.2.2 */
+static int decode8_data(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx = 0;
+
+ /* C1 .. C5 */
+ memcpy(fr->c_bits, trau_bits + 1 * 8 + 1, 5);
+ /* D1 .. D2 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 1 * 8 + 6, 2);
+ d_idx += 2;
+ /* D3 .. D8 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 2 * 8 + 2, 6);
+ /* D9 .. D57 + D'1 .. D'57 */
+ for (i = 3; i < 20; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + i * 8 + 1, 7);
+ d_idx += 7;
+ }
+ /* D'58 .. D'62 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 19 * 8 + 1, 6);
+ d_idx += 6;
+
+ return 0;
+}
+
+/* TS 08.61 Section 5.2.2 */
+static int encode8_data(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ int i, d_idx = 0;
+
+ /* sync pattern */
+ memset(trau_bits, 0, 8);
+ trau_bits[1 * 8] = 1;
+ trau_bits[2 * 8] = 0;
+ trau_bits[2 * 8 + 1] = 1;
+ for (i = 3; i < 19; i++)
+ trau_bits[i * 8] = 1;
+ trau_bits[19 * 8 + 7] = 1;
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 1 * 8 + 1, fr->c_bits, 5);
+ /* D1 .. D2 */
+ memcpy(trau_bits + 1 * 8 + 6, fr->d_bits + d_idx, 2);
+ d_idx += 2;
+ /* D3 .. D8 */
+ memcpy(trau_bits + 2 * 8 + 2, fr->d_bits + d_idx, 6);
+ /* D9 .. D57 + D'1 .. D'57 */
+ for (i = 3; i < 20; i++) {
+ memcpy(trau_bits + i * 8 + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+ /* D'58 .. D'62 */
+ memcpy(trau_bits + 19 * 8 + 1, fr->d_bits + d_idx, 6);
+ d_idx += 6;
+
+ return 20 * 8;
+}
+
+/* TS 08.61 Section 5.2.3 */
+static int decode8_oam(struct osmo_trau_frame *fr, const ubit_t *trau_bits,
+ enum osmo_trau_frame_direction dir)
+{
+ int i, d_idx = 0;
+
+ /* C1 .. C5 */
+ memcpy(fr->c_bits, trau_bits + 1 * 8 + 1, 5);
+ /* XC1 .. XC2 */
+ memcpy(fr->xc_bits, trau_bits + 1 * 8 + 6, 2);
+ /* XC3 .. XC6 */
+ memcpy(fr->xc_bits + 2, trau_bits + 2 * 8 + 2, 4);
+ /* D1 .. D2 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 2 * 8 + 6, 2);
+ d_idx += 2;
+ /* D3 .. D114 */
+ for (i = 3; i < 19; i++) {
+ memcpy(fr->d_bits + d_idx, trau_bits + i * 8 + 1, 7);
+ d_idx += 7;
+ }
+ /* D115 .. D120 */
+ memcpy(fr->d_bits + d_idx, trau_bits + 19 * 8 + 1, 6);
+ d_idx += 7;
+
+ return 0;
+}
+
+/* TS 08.61 Section 5.2.3 */
+static int encode8_oam(ubit_t *trau_bits, const struct osmo_trau_frame *fr)
+{
+ int i, d_idx = 0;
+
+ /* sync pattern */
+ memset(trau_bits, 0, 8);
+ trau_bits[1 * 8 + 0] = 1;
+ trau_bits[2 * 8 + 0] = 0;
+ trau_bits[2 * 8 + 1] = 1;
+ for (i = 3; i < 20; i++)
+ trau_bits[i * 8] = 1;
+
+ /* C1 .. C5 */
+ memcpy(trau_bits + 1 * 8 + 1, fr->c_bits, 5);
+ /* XC1 .. XC2 */
+ memcpy(trau_bits + 1 * 8 + 6, fr->xc_bits, 2);
+ /* XC3 .. XC6 */
+ memcpy(trau_bits + 2 * 8 + 2, fr->xc_bits + 2, 4);
+ /* D1 .. D2 */
+ memcpy(trau_bits + 2 * 8 + 6, fr->d_bits + d_idx, 2);
+ d_idx += 2;
+ /* D3 .. D114 */
+ for (i = 3; i < 19; i++) {
+ memcpy(trau_bits + i * 8 + 1, fr->d_bits + d_idx, 7);
+ d_idx += 7;
+ }
+ /* D115 .. D120 */
+ memcpy(trau_bits + 19 * 8 + 1, fr->d_bits + d_idx, 6);
+ d_idx += 7;
+
+ return 20 * 8;
+}
+
+
+/*! Encode a TRAU frame from its decoded representation to a sequence of unpacked bits.
+ * \param[out] bits caller-allocated buffer for unpacked outpud bits
+ * \param[in] n_bits size of 'bits' oputput buffer in number of unpacked bits
+ * \param[in] fr decoded representation of TRAU frame to be encoded
+ * \return 0 number of unpacked output bits generated; negative in case of error */
+int osmo_trau_frame_encode(ubit_t *bits, size_t n_bits, const struct osmo_trau_frame *fr)
+{
+ switch (fr->type) {
+ case OSMO_TRAU16_FT_FR:
+ case OSMO_TRAU16_FT_EFR:
+ return encode16_fr(bits, fr);
+ case OSMO_TRAU16_FT_HR:
+ return encode16_hr(bits, fr);
+ case OSMO_TRAU16_FT_AMR:
+ return encode16_amr(bits, fr);
+ case OSMO_TRAU16_FT_OAM:
+ return encode16_oam(bits, fr);
+ case OSMO_TRAU16_FT_IDLE:
+ return encode16_idle(bits, fr);
+ case OSMO_TRAU16_FT_DATA_HR:
+ return encode16_data_hr(bits, fr);
+ case OSMO_TRAU16_FT_DATA:
+ return encode16_data(bits, fr);
+ case OSMO_TRAU16_FT_D145_SYNC:
+ case OSMO_TRAU16_FT_EDATA:
+ return encode16_edata(bits, fr);
+ case OSMO_TRAU8_SPEECH:
+ return encode8_hr(bits, fr);
+ case OSMO_TRAU8_DATA:
+ return encode8_data(bits, fr);
+ case OSMO_TRAU8_OAM:
+ return encode8_oam(bits, fr);
+ case OSMO_TRAU8_AMR_LOW:
+ return encode8_amr_low(bits, fr);
+ case OSMO_TRAU8_AMR_6k7:
+ return encode8_amr_67(bits, fr);
+ case OSMO_TRAU8_AMR_7k4:
+ return encode8_amr_74(bits, fr);
+ case OSMO_TRAU_FT_NONE:
+ default:
+ return -EINVAL;
+ }
+}
+
+/*! Decode/parse a 16k TRAU frame from unpacked bits to decoded format.
+ * \param[out] fr caller-allocated output data structure
+ * \param[in] bits unpacked bits containing raw TRAU frame; must be aligned
+ * \param[in] dir direction (uplink/downlink)
+ * \returns 0 in case of success; negative on error */
+int osmo_trau_frame_decode_16k(struct osmo_trau_frame *fr, const ubit_t *bits,
+ enum osmo_trau_frame_direction dir)
+{
+ uint8_t cbits5 = get_bits(bits, 17, 5);
+
+ fr->type = OSMO_TRAU_FT_NONE;
+ fr->dir = dir;
+
+ switch (cbits5) {
+ case TRAU_FT_FR_UP:
+ case TRAU_FT_FR_DOWN:
+ fr->type = OSMO_TRAU16_FT_FR;
+ return decode16_fr(fr, bits, dir);
+ case TRAU_FT_IDLE_UP:
+ case TRAU_FT_IDLE_DOWN:
+ fr->type = OSMO_TRAU16_FT_IDLE;
+ return decode16_fr(fr, bits, dir);
+ case TRAU_FT_EFR:
+ fr->type = OSMO_TRAU16_FT_EFR;
+ return decode16_fr(fr, bits, dir);
+ case TRAU_FT_AMR:
+ fr->type = OSMO_TRAU16_FT_AMR;
+ return decode16_amr(fr, bits, dir);
+ case TRAU_FT_OM_UP:
+ case TRAU_FT_OM_DOWN:
+ fr->type = OSMO_TRAU16_FT_OAM;
+ return decode16_oam(fr, bits, dir);
+ case TRAU_FT_DATA_UP:
+ case TRAU_FT_DATA_DOWN:
+ fr->type = OSMO_TRAU16_FT_DATA;
+ return decode16_data(fr, bits, dir);
+ case TRAU_FT_HR_UP:
+ case TRAU_FT_HR_DOWN:
+ fr->type = OSMO_TRAU16_FT_HR;
+ return decode16_hr(fr, bits, dir);
+ case TRAU_FT_DATA_UP_HR:
+ case TRAU_FT_DATA_DOWN_HR:
+ fr->type = OSMO_TRAU16_FT_DATA_HR;
+ return decode16_data_hr(fr, bits, dir);
+ case TRAU_FT_EDATA:
+ fr->type = OSMO_TRAU16_FT_EDATA;
+ return decode16_edata(fr, bits, dir);
+ case TRAU_FT_D145_SYNC:
+ fr->type = OSMO_TRAU16_FT_D145_SYNC;
+ return decode16_edata(fr, bits, dir);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+#define TRAU8_FT_AMR_NO_SPEECH_CMI 0x10 /* 1, 0, 0, 0, 0 */
+#define TRAU8_FT_AMR_NO_SPEECH_CMR 0x14 /* 1, 0, 1, 0, 0 */
+#define TRAU8_FT_AMR_475_515_590 0..7
+
+const uint8_t bit8_0[16] = { 0, };
+
+/*!< check sync pattern for hr/data/oam */
+static bool is_hr(const ubit_t *bits)
+{
+ int i;
+
+ /* TS 08.61 Section 6.8.2.1.1 */
+ if (memcmp(bits, bit8_0, sizeof(bit8_0)))
+ return false;
+ if (bits[8] != 1)
+ return false;
+ if (bits[16] != 0 || bits[17] != 1)
+ return false;
+ for (i = 24; i < 20 * 8; i += 16) {
+ if (bits[i] != 1)
+ return false;
+ }
+ return true;
+}
+
+
+/*!< check sync pattern for AMR No_Speech + low bit rate */
+static bool is_amr_low(const ubit_t *bits)
+{
+ int i;
+
+ /* TS 08.61 Section 6.8.2.1.2 */
+ if (memcmp(bits, bit8_0, sizeof(bit8_0)))
+ return false;
+ if (bits[8] != 1)
+ return false;
+ if (bits[16] != 1)
+ return false;
+ if (bits[24] != 0 || bits[25] != 1)
+ return false;
+ for (i = 32; i < 20 * 8; i += 16) {
+ if (bits[i] != 1)
+ return false;
+ }
+ return true;
+}
+
+/*!< check sync pattern for AMR 6.7kBit/s */
+static bool is_amr_67(const ubit_t *bits)
+{
+ int i;
+
+ /* TS 08.61 Section 6.8.2.1.3 */
+ if (memcmp(bits, bit8_0, sizeof(bit8_0)))
+ return false;
+ if (bits[8] != 1)
+ return false;
+ if (bits[16] != 1)
+ return false;
+ if (bits[24] != 1)
+ return false;
+ if (bits[32] != 1)
+ return false;
+ if (bits[40] != 0)
+ return false;
+ for (i = 48; i < 20 * 8; i+= 16)
+ if (bits[i] != 1)
+ return false;
+
+ return true;
+}
+
+/*!< check sync pattern for AMR 7.4kBit/s */
+static bool is_amr_74(const ubit_t *bits)
+{
+ if (bits[0] != 0 || bits[1] != 0 || bits[2] != 0)
+ return false;
+ if (bits[8] != 0)
+ return false;
+ if (bits[16] != 1)
+ return false;
+ if (bits[24] != 0)
+ return false;
+
+ return true;
+}
+
+/*! Decode/parse a 8k TRAU frame from unpacked bits to decoded format.
+ * \param[out] fr caller-allocated output data structure
+ * \param[in] bits unpacked bits containing raw TRAU frame; must be aligned
+ * \param[in] dir direction (uplink/downlink)
+ * \returns 0 in case of success; negative on error */
+int osmo_trau_frame_decode_8k(struct osmo_trau_frame *fr, const ubit_t *bits,
+ enum osmo_trau_frame_direction dir)
+{
+ fr->type = OSMO_TRAU_FT_NONE;
+ fr->dir = dir;
+
+ if (is_hr(bits)) {
+ /* normal sync pattern */
+ uint8_t cbits5 = get_bits(bits, 9, 5);
+ if (dir == OSMO_TRAU_DIR_UL) {
+ switch (cbits5) { /* Section 5.2.4.1.1 */
+ case 0x02:
+ return decode8_hr(fr, bits, dir);
+ case 0x07:
+ return decode8_data(fr, bits, dir);
+ case 0x13:
+ return decode8_oam(fr, bits, dir);
+ }
+ } else {
+ /* Downlink */
+ switch (cbits5 >> 2) { /* Section 5.2.4.1.2 */
+ case 0:
+ return decode8_hr(fr, bits, dir);
+ case 1:
+ return decode8_data(fr, bits, dir);
+ case 2:
+ return decode8_oam(fr, bits, dir);
+ }
+ }
+ } else if (is_amr_low(bits)) {
+ return decode8_amr_low(fr, bits, dir);
+ } else if (is_amr_67(bits)) {
+ return decode8_amr_67(fr, bits, dir);
+ } else if (is_amr_74(bits)) {
+ return decode8_amr_74(fr, bits, dir);
+ }
+
+ return -EINVAL;
+}
+
+/* }@ */