cvsd.c

只有C源代码的一部分

                {
                        st_fail_errno(ft,errno,"debugging");
                        return (0);
                }
                fprintf(dbg.f1, "\"input\"\n");
        }
        if (!dbg.f2) {
                if (!(dbg.f2 = fopen("dbg2", "w")))
                {
                        st_fail_errno(ft,errno,"debugging");
                        return (0);
                }
                fprintf(dbg.f2, "\"recon\"\n");
        }
#endif
        for(;;) {
                /*
                 * check if the next input is due
                 */
                if (p->com.phase >= 4) {
                        if (done >= nsamp)
                                return done;
                        memmove(p->c.enc.input_filter+1, p->c.enc.input_filter,
                                sizeof(p->c.enc.input_filter)-sizeof(float));
                        p->c.enc.input_filter[0] = (*buf++) /
                                ((float)ST_SAMPLE_MAX);
                        done++;
                }
                p->com.phase &= 3;
                /* insert input filter here! */
                inval = float_conv(p->c.enc.input_filter,
                                   (p->cvsd_rate < 24000) ?
                                   (enc_filter_16[(p->com.phase >= 2)]) :
                                   (enc_filter_32[p->com.phase]),
                                   ENC_FILTERLEN);
                /*
                 * encode one bit
                 */
                p->com.overload = (((p->com.overload << 1) |
                                    (inval >  p->c.enc.recon_int)) & 7);
                p->com.mla_int *= p->com.mla_tc0;
                if ((p->com.overload == 0) || (p->com.overload == 7))
                        p->com.mla_int += p->com.mla_tc1;
                if (p->com.mla_int > p->com.v_max)
                        p->com.v_max = p->com.mla_int;
                if (p->com.mla_int < p->com.v_min)
                        p->com.v_min = p->com.mla_int;
                if (p->com.overload & 1) {
                        p->c.enc.recon_int += p->com.mla_int;
                        p->bit.shreg |= p->bit.mask;
                } else
                        p->c.enc.recon_int -= p->com.mla_int;
                if ((++(p->bit.cnt)) >= 8) {
                        st_writeb(ft, p->bit.shreg);
                        p->bytes_written++;
                        p->bit.shreg = p->bit.cnt = 0;
                        p->bit.mask = p->swapbits ? 0x80 : 1;
                } else {
                        if (p->swapbits)
                                p->bit.mask >>= 1;
                        else
                                p->bit.mask <<= 1;
                }
                p->com.phase += p->com.phase_inc;
#ifdef DEBUG
                fprintf(dbg.f1, "%f %f\n", (double)dbg.cnt, (double)inval);
                fprintf(dbg.f2, "%f %f\n", (double)dbg.cnt,
                        (double)p->c.enc.recon_int);
                dbg.cnt++;
#endif
        }
}

/* ---------------------------------------------------------------------- */
/*
 * DVMS file header
 */
struct dvms_header {
        char          Filename[14];
        unsigned      Id;
        unsigned      State;
        time_t        Unixtime;
        unsigned      Usender;
        unsigned      Ureceiver;
        st_size_t     Length;
        unsigned      Srate;
        unsigned      Days;
        unsigned      Custom1;
        unsigned      Custom2;
        char          Info[16];
        char          extend[64];
        unsigned      Crc;
};

#define DVMS_HEADER_LEN 120

/* ---------------------------------------------------------------------- */
/* FIXME: Move these to misc.c */
static uint32_t get32(unsigned char **p)
{
        uint32_t val = (((*p)[3]) << 24) | (((*p)[2]) << 16) |
                (((*p)[1]) << 8) | (**p);
        (*p) += 4;
        return val;
}

static uint16_t get16(unsigned char **p)
{
        unsigned val = (((*p)[1]) << 8) | (**p);
        (*p) += 2;
        return val;
}

static void put32(unsigned char **p, uint32_t val)
{
        *(*p)++ = val & 0xff;
        *(*p)++ = (val >> 8) & 0xff;
        *(*p)++ = (val >> 16) & 0xff;
        *(*p)++ = (val >> 24) & 0xff;
}

static void put16(unsigned char **p, int16_t val)
{
        *(*p)++ = val & 0xff;
        *(*p)++ = (val >> 8) & 0xff;
}

/* ---------------------------------------------------------------------- */

static int dvms_read_header(FILE *f, struct dvms_header *hdr)
{
        unsigned char hdrbuf[DVMS_HEADER_LEN];
        unsigned char *pch = hdrbuf;
        int i;
        unsigned sum;

        if (fread(hdrbuf, sizeof(hdrbuf), 1, f) != 1)
        {
                return (ST_EOF);
        }
        for(i = sizeof(hdrbuf), sum = 0; i > /*2*/3; i--) /* Deti bug */
                sum += *pch++;
        pch = hdrbuf;
        memcpy(hdr->Filename, pch, sizeof(hdr->Filename));
        pch += sizeof(hdr->Filename);
        hdr->Id = get16(&pch);
        hdr->State = get16(&pch);
        hdr->Unixtime = get32(&pch);
        hdr->Usender = get16(&pch);
        hdr->Ureceiver = get16(&pch);
        hdr->Length = get32(&pch);
        hdr->Srate = get16(&pch);
        hdr->Days = get16(&pch);
        hdr->Custom1 = get16(&pch);
        hdr->Custom2 = get16(&pch);
        memcpy(hdr->Info, pch, sizeof(hdr->Info));
        pch += sizeof(hdr->Info);
        memcpy(hdr->extend, pch, sizeof(hdr->extend));
        pch += sizeof(hdr->extend);
        hdr->Crc = get16(&pch);
        if (sum != hdr->Crc)
        {
                st_report("DVMS header checksum error, read %u, calculated %u\n",
                     hdr->Crc, sum);
                return (ST_EOF);
        }
        return (ST_SUCCESS);
}

/* ---------------------------------------------------------------------- */

/*
 * note! file must be seekable
 */
static int dvms_write_header(FILE *f, struct dvms_header *hdr)
{
        unsigned char hdrbuf[DVMS_HEADER_LEN];
        unsigned char *pch = hdrbuf;
        unsigned char *pchs = hdrbuf;
        int i;
        unsigned sum;

        memcpy(pch, hdr->Filename, sizeof(hdr->Filename));
        pch += sizeof(hdr->Filename);
        put16(&pch, hdr->Id);
        put16(&pch, hdr->State);
        put32(&pch, hdr->Unixtime);
        put16(&pch, hdr->Usender);
        put16(&pch, hdr->Ureceiver);
        put32(&pch, hdr->Length);
        put16(&pch, hdr->Srate);
        put16(&pch, hdr->Days);
        put16(&pch, hdr->Custom1);
        put16(&pch, hdr->Custom2);
        memcpy(pch, hdr->Info, sizeof(hdr->Info));
        pch += sizeof(hdr->Info);
        memcpy(pch, hdr->extend, sizeof(hdr->extend));
        pch += sizeof(hdr->extend);
        for(i = sizeof(hdrbuf), sum = 0; i > /*2*/3; i--) /* Deti bug */
                sum += *pchs++;
        hdr->Crc = sum;
        put16(&pch, hdr->Crc);
        if (fseek(f, 0, SEEK_SET) < 0)
        {
                st_report("seek failed\n: %s",strerror(errno));
                return (ST_EOF);
        }
        if (fwrite(hdrbuf, sizeof(hdrbuf), 1, f) != 1)
        {
                st_report("%s\n",strerror(errno));
                return (ST_EOF);
        }
        return (ST_SUCCESS);
}

/* ---------------------------------------------------------------------- */

static void make_dvms_hdr(ft_t ft, struct dvms_header *hdr)
{
        struct cvsdpriv *p = (struct cvsdpriv *) ft->priv;
        size_t len;

        memset(hdr->Filename, 0, sizeof(hdr->Filename));
        len = strlen(ft->filename);
        if (len >= sizeof(hdr->Filename))
                len = sizeof(hdr->Filename)-1;
        memcpy(hdr->Filename, ft->filename, len);
        hdr->Id = hdr->State = 0;
        hdr->Unixtime = time(NULL);
        hdr->Usender = hdr->Ureceiver = 0;
        hdr->Length = p->bytes_written;
        hdr->Srate = p->cvsd_rate/100;
        hdr->Days = hdr->Custom1 = hdr->Custom2 = 0;
        memset(hdr->Info, 0, sizeof(hdr->Info));
        len = strlen(ft->comment);
        if (len >= sizeof(hdr->Info))
                len = sizeof(hdr->Info)-1;
        memcpy(hdr->Info, ft->comment, len);
        memset(hdr->extend, 0, sizeof(hdr->extend));
}

/* ---------------------------------------------------------------------- */

int st_dvmsstartread(ft_t ft)
{
        struct cvsdpriv *p = (struct cvsdpriv *) ft->priv;
        struct dvms_header hdr;
        int rc;

        rc = dvms_read_header(ft->fp, &hdr);
        if (rc){
            st_fail_errno(ft,ST_EHDR,"unable to read DVMS header\n");
            return rc;
        }

        st_report("DVMS header of source file \"%s\":");
        st_report("  filename  \"%.14s\"",ft->filename);
        st_report("  id        0x%x", hdr.Filename);
        st_report("  state     0x%x", hdr.Id, hdr.State);
        st_report("  time      %s",ctime(&hdr.Unixtime)); /* ctime generates lf */
        st_report("  usender   %u", hdr.Usender);
        st_report("  ureceiver %u", hdr.Ureceiver);
        st_report("  length    %u", hdr.Length);
        st_report("  srate     %u", hdr.Srate);
        st_report("  days      %u", hdr.Days);
        st_report("  custom1   %u", hdr.Custom1);
        st_report("  custom2   %u", hdr.Custom2);
        st_report("  info      \"%.16s\"\n", hdr.Info);
        ft->info.rate = (hdr.Srate < 240) ? 16000 : 32000;
        st_report("DVMS rate %dbit/s using %dbit/s deviation %d%%\n",
               hdr.Srate*100, ft->info.rate,
               ((ft->info.rate - hdr.Srate*100) * 100) / ft->info.rate);
        rc = st_cvsdstartread(ft);
        if (rc)
            return rc;

        p->swapbits = 0;
        return(ST_SUCCESS);
}

/* ---------------------------------------------------------------------- */

int st_dvmsstartwrite(ft_t ft)
{
        struct cvsdpriv *p = (struct cvsdpriv *) ft->priv;
        struct dvms_header hdr;
        int rc;

        rc = st_cvsdstartwrite(ft);
        if (rc)
            return rc;

        make_dvms_hdr(ft, &hdr);
        rc = dvms_write_header(ft->fp, &hdr);
        if (rc){
                st_fail_errno(ft,rc,"cannot write DVMS header\n");
            return rc;
        }

        if (!ft->seekable)
               st_warn("Length in output .DVMS header will wrong since can't seek to fix it");

        p->swapbits = 0;
        return(ST_SUCCESS);
}

/* ---------------------------------------------------------------------- */

int st_dvmsstopwrite(ft_t ft)
{
        struct dvms_header hdr;
        int rc;

        st_cvsdstopwrite(ft);
        if (!ft->seekable)
        {
            st_warn("File not seekable");
            return (ST_EOF);
        }
        if (fseek(ft->fp, 0L, 0) != 0)
        {
                st_fail_errno(ft,errno,"Can't rewind output file to rewrite DVMS header.");
                return(ST_EOF);
        }
        make_dvms_hdr(ft, &hdr);
        rc = dvms_write_header(ft->fp, &hdr);
        if(rc){
            st_fail_errno(ft,rc,"cannot write DVMS header\n");
            return rc;
        }
        return rc;
}

/* ---------------------------------------------------------------------- */