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capi-hacks/hdlr_spandsp.c

170 lines
4.2 KiB

/* soft-modem B-channel based on spandsp library */
#include <unistd.h>
#include <osmocom/core/utils.h>
#include <osmocom/core/bits.h>
#include <osmocom/core/logging.h>
#include <spandsp/telephony.h>
#include <spandsp/g711.h>
#include <spandsp/logging.h>
#include <spandsp/alloc.h>
#include <spandsp/at_interpreter.h>
#include <spandsp/async.h>
#include <spandsp/data_modems.h>
#include "bchan.h"
#include "errno.h"
/***********************************************************************
* spandsp callbacks
***********************************************************************/
static int cb_at_tx_handler(void *user_data, const uint8_t *buf, size_t len)
{
/* write to stdout for now */
return write(1, buf, len);
}
static int cb_modem_ctrl_hdlr(data_modems_state_t *ms, void *user_data, int op, const char *num)
{
printf("MODEM CONTROL: %s\n", at_modem_control_to_str(op));
switch (op) {
case AT_MODEM_CONTROL_CALL:
data_modems_call_event(ms, AT_CALL_EVENT_CONNECTED);
break;
case AT_MODEM_CONTROL_ANSWER:
data_modems_call_event(ms, AT_CALL_EVENT_ANSWERED);
break;
}
return 0;
}
static void cb_put_msg(void *user_data, const uint8_t msg[], int len)
{
if (len < 0)
printf("Status %s\n", signal_status_to_str(len));
else
printf("Put %d '%s'\n", len, msg);
}
static int cb_get_msg(void *user_data, uint8_t msg[], int len)
{
return 0;
}
/***********************************************************************
* bchan integration
***********************************************************************/
struct spandsp_priv {
data_modems_state_t *ms;
g711_state_t *g711;
};
static int spandsp_init(struct call_state *cst)
{
struct spandsp_priv *rpp;
logging_state_t *logging;
rpp = cst->priv = talloc_zero(cst, struct spandsp_priv);
if (!rpp)
return -ENOMEM;
rpp->ms = data_modems_init(NULL, false, cb_at_tx_handler, NULL, cb_modem_ctrl_hdlr,
NULL, cb_put_msg, cb_get_msg, rpp);
OSMO_ASSERT(rpp->ms);
logging = data_modems_get_logging_state(rpp->ms);
span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
span_log_set_tag(logging, "modem");
/* this is the default, but calling it now applies above-mentioned log level */
data_modems_set_modem_type(rpp->ms, DATA_MODEM_V8, 0, 0);
//data_modems_set_modem_type(rpp->ms, DATA_MODEM_BELL103, 0, 0);
rpp->g711 = g711_init(NULL, G711_ALAW);
data_modems_call_event(rpp->ms, AT_CALL_EVENT_ANSWERED);
return 0;
}
static void spandsp_rx(struct call_state *cst, const uint8_t *data, size_t len)
{
struct spandsp_priv *rpp = cst->priv;
int16_t s16_buf[len];
uint8_t tx_buf[len];
int rc;
/* mISDN/CAPI bit order != spandsp order */
osmo_revbytebits_buf((uint8_t *)data, len);
/* A-law -> S16 */
rc = g711_decode(rpp->g711, s16_buf, data, len);
OSMO_ASSERT(rc == len);
rc = data_modems_rx(rpp->ms, s16_buf, len);
OSMO_ASSERT(rc == 0);
/* generate respective number of output samples and transmit them */
rc = data_modems_tx(rpp->ms, s16_buf, len);
OSMO_ASSERT(rc == len);
/* A-law <- S16 */
rc = g711_encode(rpp->g711, tx_buf, s16_buf, len);
OSMO_ASSERT(rc == len);
/* mISDN/CAPI bit order != spandsp order */
osmo_revbytebits_buf(tx_buf, len);
bchan_call_tx(cst, tx_buf, len);
}
static void spandsp_fini(struct call_state *cst)
{
struct spandsp_priv *rpp = cst->priv;
g711_free(rpp->g711);
data_modems_free(rpp->ms);
talloc_free(rpp);
cst->priv = NULL;
}
static void spandsp_log_cb(void *user_data, int level, const char *text)
{
LOGP(DCAPI, LOGL_INFO, text);
}
static struct bchan_handler bch_spandsp = {
.name = "spandsp",
.cfg = {
.proto = { CAPI_B1_64k_TRANSPARENT, CAPI_B2_TRANSPARENT, CAPI_B3_TRANSPARENT },
.ncpi = NULL,
.max_b_data_blocks = 10,
.max_b_data_len = 32,
},
.ops = {
.init = spandsp_init,
.rx_data = spandsp_rx,
.fini = spandsp_fini,
},
};
static void *span_alloc_cb(size_t size)
{
return talloc_size(g_ctx, size);
}
static void span_free_cb(void *ptr)
{
talloc_free(ptr);
}
static __attribute__((constructor)) void hdlr_spandsp_init(void)
{
/* memory allocator */
span_mem_allocators(span_alloc_cb, NULL, span_free_cb, NULL, NULL);
/* logging */
//span_set_message_handler(spandsp_log_cb, NULL);
bchan_handler_register(&bch_spandsp);
}