audio.c

qemu虚拟机代码

    switch (as->fmt) {
    case AUD_FMT_S8:
        AUD_log (NULL, "S8");
        break;
    case AUD_FMT_U8:
        AUD_log (NULL, "U8");
        break;
    case AUD_FMT_S16:
        AUD_log (NULL, "S16");
        break;
    case AUD_FMT_U16:
        AUD_log (NULL, "U16");
        break;
    default:
        AUD_log (NULL, "invalid(%d)", as->fmt);
        break;
    }
    AUD_log (NULL, "\n");
}

static int audio_validate_settigs (audsettings_t *as)
{
    int invalid;

    invalid = as->nchannels != 1 && as->nchannels != 2;

    switch (as->fmt) {
    case AUD_FMT_S8:
    case AUD_FMT_U8:
    case AUD_FMT_S16:
    case AUD_FMT_U16:
        break;
    default:
        invalid = 1;
        break;
    }

    invalid |= as->freq <= 0;

    if (invalid) {
        return -1;
    }
    return 0;
}

static int audio_pcm_info_eq (struct audio_pcm_info *info, audsettings_t *as)
{
    int bits = 8, sign = 0;

    switch (as->fmt) {
    case AUD_FMT_S8:
        sign = 1;
    case AUD_FMT_U8:
        break;

    case AUD_FMT_S16:
        sign = 1;
    case AUD_FMT_U16:
        bits = 16;
        break;
    }
    return info->freq == as->freq
        && info->nchannels == as->nchannels
        && info->sign == sign
        && info->bits == bits;
}

void audio_pcm_init_info (
    struct audio_pcm_info *info,
    audsettings_t *as,
    int swap_endian
    )
{
    int bits = 8, sign = 0;

    switch (as->fmt) {
    case AUD_FMT_S8:
        sign = 1;
    case AUD_FMT_U8:
        break;

    case AUD_FMT_S16:
        sign = 1;
    case AUD_FMT_U16:
        bits = 16;
        break;
    }

    info->freq = as->freq;
    info->bits = bits;
    info->sign = sign;
    info->nchannels = as->nchannels;
    info->shift = (as->nchannels == 2) + (bits == 16);
    info->align = (1 << info->shift) - 1;
    info->bytes_per_second = info->freq << info->shift;
    info->swap_endian = swap_endian;
}

void audio_pcm_info_clear_buf (struct audio_pcm_info *info, void *buf, int len)
{
    if (!len) {
        return;
    }

    if (info->sign) {
        memset (buf, len << info->shift, 0x00);
    }
    else {
        if (info->bits == 8) {
            memset (buf, len << info->shift, 0x80);
        }
        else {
            int i;
            uint16_t *p = buf;
            int shift = info->nchannels - 1;
            short s = INT16_MAX;

            if (info->swap_endian) {
                s = bswap16 (s);
            }

            for (i = 0; i < len << shift; i++) {
                p[i] = s;
            }
        }
    }
}

/*
 * Hard voice (capture)
 */
static int audio_pcm_hw_find_min_in (HWVoiceIn *hw)
{
    SWVoiceIn *sw;
    int m = hw->total_samples_captured;

    for (sw = hw->sw_head.lh_first; sw; sw = sw->entries.le_next) {
        if (sw->active) {
            m = audio_MIN (m, sw->total_hw_samples_acquired);
        }
    }
    return m;
}

int audio_pcm_hw_get_live_in (HWVoiceIn *hw)
{
    int live = hw->total_samples_captured - audio_pcm_hw_find_min_in (hw);
    if (audio_bug (AUDIO_FUNC, live < 0 || live > hw->samples)) {
        dolog ("live=%d hw->samples=%d\n", live, hw->samples);
        return 0;
    }
    return live;
}

/*
 * Soft voice (capture)
 */
static int audio_pcm_sw_get_rpos_in (SWVoiceIn *sw)
{
    HWVoiceIn *hw = sw->hw;
    int live = hw->total_samples_captured - sw->total_hw_samples_acquired;
    int rpos;

    if (audio_bug (AUDIO_FUNC, live < 0 || live > hw->samples)) {
        dolog ("live=%d hw->samples=%d\n", live, hw->samples);
        return 0;
    }

    rpos = hw->wpos - live;
    if (rpos >= 0) {
        return rpos;
    }
    else {
        return hw->samples + rpos;
    }
}

int audio_pcm_sw_read (SWVoiceIn *sw, void *buf, int size)
{
    HWVoiceIn *hw = sw->hw;
    int samples, live, ret = 0, swlim, isamp, osamp, rpos, total = 0;
    st_sample_t *src, *dst = sw->buf;

    rpos = audio_pcm_sw_get_rpos_in (sw) % hw->samples;

    live = hw->total_samples_captured - sw->total_hw_samples_acquired;
    if (audio_bug (AUDIO_FUNC, live < 0 || live > hw->samples)) {
        dolog ("live_in=%d hw->samples=%d\n", live, hw->samples);
        return 0;
    }

    samples = size >> sw->info.shift;
    if (!live) {
        return 0;
    }

    swlim = (live * sw->ratio) >> 32;
    swlim = audio_MIN (swlim, samples);

    while (swlim) {
        src = hw->conv_buf + rpos;
        isamp = hw->wpos - rpos;
        /* XXX: <= ? */
        if (isamp <= 0) {
            isamp = hw->samples - rpos;
        }

        if (!isamp) {
            break;
        }
        osamp = swlim;

        if (audio_bug (AUDIO_FUNC, osamp < 0)) {
            dolog ("osamp=%d\n", osamp);
            return 0;
        }

        st_rate_flow (sw->rate, src, dst, &isamp, &osamp);
        swlim -= osamp;
        rpos = (rpos + isamp) % hw->samples;
        dst += osamp;
        ret += osamp;
        total += isamp;
    }

    sw->clip (buf, sw->buf, ret);
    sw->total_hw_samples_acquired += total;
    return ret << sw->info.shift;
}

/*
 * Hard voice (playback)
 */
static int audio_pcm_hw_find_min_out (HWVoiceOut *hw, int *nb_livep)
{
    SWVoiceOut *sw;
    int m = INT_MAX;
    int nb_live = 0;

    for (sw = hw->sw_head.lh_first; sw; sw = sw->entries.le_next) {
        if (sw->active || !sw->empty) {
            m = audio_MIN (m, sw->total_hw_samples_mixed);
            nb_live += 1;
        }
    }

    *nb_livep = nb_live;
    return m;
}

int audio_pcm_hw_get_live_out2 (HWVoiceOut *hw, int *nb_live)
{
    int smin;

    smin = audio_pcm_hw_find_min_out (hw, nb_live);

    if (!*nb_live) {
        return 0;
    }
    else {
        int live = smin;

        if (audio_bug (AUDIO_FUNC, live < 0 || live > hw->samples)) {
            dolog ("live=%d hw->samples=%d\n", live, hw->samples);
            return 0;
        }
        return live;
    }
}

int audio_pcm_hw_get_live_out (HWVoiceOut *hw)
{
    int nb_live;
    int live;

    live = audio_pcm_hw_get_live_out2 (hw, &nb_live);
    if (audio_bug (AUDIO_FUNC, live < 0 || live > hw->samples)) {
        dolog ("live=%d hw->samples=%d\n", live, hw->samples);
        return 0;
    }
    return live;
}

/*
 * Soft voice (playback)
 */
int audio_pcm_sw_write (SWVoiceOut *sw, void *buf, int size)
{
    int hwsamples, samples, isamp, osamp, wpos, live, dead, left, swlim, blck;
    int ret = 0, pos = 0, total = 0;

    if (!sw) {
        return size;
    }

    hwsamples = sw->hw->samples;

    live = sw->total_hw_samples_mixed;
    if (audio_bug (AUDIO_FUNC, live < 0 || live > hwsamples)){
        dolog ("live=%d hw->samples=%d\n", live, hwsamples);
        return 0;
    }

    if (live == hwsamples) {
        return 0;
    }

    wpos = (sw->hw->rpos + live) % hwsamples;
    samples = size >> sw->info.shift;

    dead = hwsamples - live;
    swlim = ((int64_t) dead << 32) / sw->ratio;
    swlim = audio_MIN (swlim, samples);
    if (swlim) {
        sw->conv (sw->buf, buf, swlim, &sw->vol);
    }

    while (swlim) {
        dead = hwsamples - live;
        left = hwsamples - wpos;
        blck = audio_MIN (dead, left);
        if (!blck) {
            break;
        }
        isamp = swlim;
        osamp = blck;
        st_rate_flow_mix (
            sw->rate,
            sw->buf + pos,
            sw->hw->mix_buf + wpos,
            &isamp,
            &osamp
            );
        ret += isamp;
        swlim -= isamp;
        pos += isamp;
        live += osamp;
        wpos = (wpos + osamp) % hwsamples;
        total += osamp;
    }

    sw->total_hw_samples_mixed += total;
    sw->empty = sw->total_hw_samples_mixed == 0;

#ifdef DEBUG_OUT
    dolog (
        "%s: write size %d ret %d total sw %d\n",
        SW_NAME (sw),
        size >> sw->info.shift,
        ret,
        sw->total_hw_samples_mixed
        );
#endif

    return ret << sw->info.shift;
}

#ifdef DEBUG_AUDIO
static void audio_pcm_print_info (const char *cap, struct audio_pcm_info *info)
{
    dolog ("%s: bits %d, sign %d, freq %d, nchan %d\n",
           cap, info->bits, info->sign, info->freq, info->nchannels);
}
#endif

#define DAC
#include "audio_template.h"
#undef DAC
#include "audio_template.h"

int AUD_write (SWVoiceOut *sw, void *buf, int size)
{
    int bytes;

    if (!sw) {
        /* XXX: Consider options */
        return size;
    }

    if (!sw->hw->enabled) {
        dolog ("Writing to disabled voice %s\n", SW_NAME (sw));
        return 0;
    }

    bytes = sw->hw->pcm_ops->write (sw, buf, size);
    return bytes;
}

int AUD_read (SWVoiceIn *sw, void *buf, int size)
{
    int bytes;

    if (!sw) {
        /* XXX: Consider options */
        return size;
    }

    if (!sw->hw->enabled) {
        dolog ("Reading from disabled voice %s\n", SW_NAME (sw));
        return 0;
    }

    bytes = sw->hw->pcm_ops->read (sw, buf, size);
    return bytes;
}

int AUD_get_buffer_size_out (SWVoiceOut *sw)
{
    return sw->hw->samples << sw->hw->info.shift;
}

void AUD_set_active_out (SWVoiceOut *sw, int on)
{
    HWVoiceOut *hw;

    if (!sw) {
        return;
    }

    hw = sw->hw;
    if (sw->active != on) {
        SWVoiceOut *temp_sw;

        if (on) {
            int total;

            hw->pending_disable = 0;
            if (!hw->enabled) {
                hw->enabled = 1;
                hw->pcm_ops->ctl_out (hw, VOICE_ENABLE);
            }

            if (sw->empty) {
                total = 0;
            }
        }
        else {
            if (hw->enabled) {
                int nb_active = 0;

                for (temp_sw = hw->sw_head.lh_first; temp_sw;
                     temp_sw = temp_sw->entries.le_next) {
                    nb_active += temp_sw->active != 0;
                }

                hw->pending_disable = nb_active == 1;
            }
        }
        sw->active = on;
    }
}

void AUD_set_active_in (SWVoiceIn *sw, int on)
{
    HWVoiceIn *hw;

    if (!sw) {
        return;
    }

    hw = sw->hw;
    if (sw->active != on) {
        SWVoiceIn *temp_sw;

        if (on) {
            if (!hw->enabled) {
                hw->enabled = 1;
                hw->pcm_ops->ctl_in (hw, VOICE_ENABLE);
            }
            sw->total_hw_samples_acquired = hw->total_samples_captured;
        }
        else {
            if (hw->enabled) {
                int nb_active = 0;

                for (temp_sw = hw->sw_head.lh_first; temp_sw;
                     temp_sw = temp_sw->entries.le_next) {
                    nb_active += temp_sw->active != 0;
                }

                if (nb_active == 1) {
                    hw->enabled = 0;
                    hw->pcm_ops->ctl_in (hw, VOICE_DISABLE);
                }
            }
        }
        sw->active = on;
    }
}

static int audio_get_avail (SWVoiceIn *sw)
{
    int live;