diff options
Diffstat (limited to 'src/codec/ecu.c')
| -rw-r--r-- | src/codec/ecu.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/src/codec/ecu.c b/src/codec/ecu.c new file mode 100644 index 00000000..db7148ce --- /dev/null +++ b/src/codec/ecu.c @@ -0,0 +1,118 @@ +/* Core infrastructure for ECU implementations */ + +/* (C) 2019 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 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. + * + */ + +/* As the developer and copyright holder of the related code, I hereby + * state that any ECU implementation using 'struct osmo_ecu_ops' and + * registering with the 'osmo_ecu_register()' function shall not be + * considered as a derivative work under any applicable copyright law; + * the copyleft terms of GPLv2 shall hence not apply to any such ECU + * implementation. + * + * The intent of the above exception is to allow anyone to combine third + * party Error Concealment Unit implementations with libosmocodec. + * including but not limited to such published by ETSI. + * + * -- Harald Welte <laforge@gnumonks.org> on August 1, 2019. + */ + +#include <string.h> +#include <errno.h> + +#include <osmocom/codec/ecu.h> +#include <osmocom/core/talloc.h> + +static const struct osmo_ecu_ops *g_ecu_ops[_NUM_OSMO_ECU_CODECS]; + +/*********************************************************************** + * high-level API for users + ***********************************************************************/ + +/*! initialize an ECU instance for given codec. + * \param[in] ctx talloc context from which to allocate + * \parma[in] codec codec for which to initialize/create ECU */ +struct osmo_ecu_state *osmo_ecu_init(void *ctx, enum osmo_ecu_codec codec) +{ + if (codec >= ARRAY_SIZE(g_ecu_ops)) + return NULL; + if (!g_ecu_ops[codec] || !g_ecu_ops[codec]->init) + return NULL; + return g_ecu_ops[codec]->init(ctx, codec); +} + +/*! destroy an ECU instance */ +void osmo_ecu_destroy(struct osmo_ecu_state *st) +{ + if (st->codec >= ARRAY_SIZE(g_ecu_ops)) + return; + if (!g_ecu_ops[st->codec]) + return; + + if (!g_ecu_ops[st->codec]->destroy) + talloc_free(st); + else + g_ecu_ops[st->codec]->destroy(st); +} + +/*! process a received frame a substitute/erroneous frame. + * \param[in] st ECU state/instance on which to operate + * \param[in] bfi Bad Frame Indication + * \param[in] frame received codec frame to be processed + * \param[in] frame_bytes number of bytes available in frame */ +int osmo_ecu_frame_in(struct osmo_ecu_state *st, bool bfi, + const uint8_t *frame, unsigned int frame_bytes) +{ + if (st->codec >= ARRAY_SIZE(g_ecu_ops)) + return -EINVAL; + if (!g_ecu_ops[st->codec]) + return -EBUSY; + return g_ecu_ops[st->codec]->frame_in(st, bfi, frame, frame_bytes); +} + +/*! generate output data for a substitute/erroneous frame. + * \param[in] st ECU state/instance on which to operate + * \param[out] frame_out buffer for generated output frame + * \return number of bytes written to frame_out; negative on error */ +int osmo_ecu_frame_out(struct osmo_ecu_state *st, uint8_t *frame_out) +{ + if (st->codec >= ARRAY_SIZE(g_ecu_ops)) + return -EINVAL; + if (!g_ecu_ops[st->codec]) + return -EBUSY; + return g_ecu_ops[st->codec]->frame_out(st, frame_out); +} + +/*********************************************************************** + * low-level API for ECU implementations + ***********************************************************************/ + +/*! register an ECU implementation for a given codec */ +int osmo_ecu_register(const struct osmo_ecu_ops *ops, enum osmo_ecu_codec codec) +{ + if (codec >= ARRAY_SIZE(g_ecu_ops)) + return -EINVAL; + if (g_ecu_ops[codec]) + return -EBUSY; + + g_ecu_ops[codec] = ops; + + return 0; +} |