audio.c

xen虚拟机源代码安装包

/*
 * QEMU Audio subsystem
 *
 * Copyright (c) 2003-2005 Vassili Karpov (malc)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "vl.h"

#define AUDIO_CAP "audio"
#include "audio_int.h"

/* #define DEBUG_PLIVE */
/* #define DEBUG_LIVE */
/* #define DEBUG_OUT */
/* #define DEBUG_CAPTURE */

#define SW_NAME(sw) (sw)->name ? (sw)->name : "unknown"

static struct audio_driver *drvtab[] = {
#ifdef CONFIG_OSS
    &oss_audio_driver,
#endif
#ifdef CONFIG_ALSA
    &alsa_audio_driver,
#endif
#ifdef CONFIG_COREAUDIO
    &coreaudio_audio_driver,
#endif
#ifdef CONFIG_DSOUND
    &dsound_audio_driver,
#endif
#ifdef CONFIG_FMOD
    &fmod_audio_driver,
#endif
#ifdef CONFIG_SDL
    &sdl_audio_driver,
#endif
    &no_audio_driver,
    &wav_audio_driver
};

struct fixed_settings {
    int enabled;
    int nb_voices;
    int greedy;
    audsettings_t settings;
};

static struct {
    struct fixed_settings fixed_out;
    struct fixed_settings fixed_in;
    union {
        int hz;
        int64_t ticks;
    } period;
    int plive;
    int log_to_monitor;
} conf = {
    {                           /* DAC fixed settings */
        1,                      /* enabled */
        1,                      /* nb_voices */
        1,                      /* greedy */
        {
            44100,              /* freq */
            2,                  /* nchannels */
            AUD_FMT_S16         /* fmt */
        }
    },

    {                           /* ADC fixed settings */
        1,                      /* enabled */
        1,                      /* nb_voices */
        1,                      /* greedy */
        {
            44100,              /* freq */
            2,                  /* nchannels */
            AUD_FMT_S16         /* fmt */
        }
    },

    { 0 },                      /* period */
    0,                          /* plive */
    0                           /* log_to_monitor */
};

static AudioState glob_audio_state;

volume_t nominal_volume = {
    0,
#ifdef FLOAT_MIXENG
    1.0,
    1.0
#else
    UINT_MAX,
    UINT_MAX
#endif
};

/* http://www.df.lth.se/~john_e/gems/gem002d.html */
/* http://www.multi-platforms.com/Tips/PopCount.htm */
uint32_t popcount (uint32_t u)
{
    u = ((u&0x55555555) + ((u>>1)&0x55555555));
    u = ((u&0x33333333) + ((u>>2)&0x33333333));
    u = ((u&0x0f0f0f0f) + ((u>>4)&0x0f0f0f0f));
    u = ((u&0x00ff00ff) + ((u>>8)&0x00ff00ff));
    u = ( u&0x0000ffff) + (u>>16);
    return u;
}

inline uint32_t lsbindex (uint32_t u)
{
    return popcount ((u&-u)-1);
}

#ifdef AUDIO_IS_FLAWLESS_AND_NO_CHECKS_ARE_REQURIED
#error No its not
#else
int audio_bug (const char *funcname, int cond)
{
    if (cond) {
        static int shown;

        AUD_log (NULL, "A bug was just triggered in %s\n", funcname);
        if (!shown) {
            shown = 1;
            AUD_log (NULL, "Save all your work and restart without audio\n");
            AUD_log (NULL, "Please send bug report to [e-mail]\n");
            AUD_log (NULL, "I am sorry\n");
        }
        AUD_log (NULL, "Context:\n");

#if defined AUDIO_BREAKPOINT_ON_BUG
#  if defined HOST_I386
#    if defined __GNUC__
        __asm__ ("int3");
#    elif defined _MSC_VER
        _asm _emit 0xcc;
#    else
        abort ();
#    endif
#  else
        abort ();
#  endif
#endif
    }

    return cond;
}
#endif

void *audio_calloc (const char *funcname, int nmemb, size_t size)
{
    int cond;
    size_t len;

    len = nmemb * size;
    cond = !nmemb || !size;
    cond |= nmemb < 0;
    cond |= len < size;

    if (audio_bug ("audio_calloc", cond)) {
        AUD_log (NULL, "%s passed invalid arguments to audio_calloc\n",
                 funcname);
        AUD_log (NULL, "nmemb=%d size=%zu (len=%zu)\n", nmemb, size, len);
        return NULL;
    }

    return qemu_mallocz (len);
}

static char *audio_alloc_prefix (const char *s)
{
    const char qemu_prefix[] = "QEMU_";
    size_t len;
    char *r;

    if (!s) {
        return NULL;
    }

    len = strlen (s);
    r = qemu_malloc (len + sizeof (qemu_prefix));

    if (r) {
        size_t i;
        char *u = r + sizeof (qemu_prefix) - 1;

        strcpy (r, qemu_prefix);
        strcat (r, s);

        for (i = 0; i < len; ++i) {
            u[i] = toupper ((uint8_t)u[i]);
        }
    }
    return r;
}

const char *audio_audfmt_to_string (audfmt_e fmt)
{
    switch (fmt) {
    case AUD_FMT_U8:
        return "U8";

    case AUD_FMT_U16:
        return "U16";

    case AUD_FMT_S8:
        return "S8";

    case AUD_FMT_S16:
        return "S16";
    }

    dolog ("Bogus audfmt %d returning S16\n", fmt);
    return "S16";
}

audfmt_e audio_string_to_audfmt (const char *s, audfmt_e defval, int *defaultp)
{
    if (!strcasecmp (s, "u8")) {
        *defaultp = 0;
        return AUD_FMT_U8;
    }
    else if (!strcasecmp (s, "u16")) {
        *defaultp = 0;
        return AUD_FMT_U16;
    }
    else if (!strcasecmp (s, "s8")) {
        *defaultp = 0;
        return AUD_FMT_S8;
    }
    else if (!strcasecmp (s, "s16")) {
        *defaultp = 0;
        return AUD_FMT_S16;
    }
    else {
        dolog ("Bogus audio format `%s' using %s\n",
               s, audio_audfmt_to_string (defval));
        *defaultp = 1;
        return defval;
    }
}

static audfmt_e audio_get_conf_fmt (const char *envname,
                                    audfmt_e defval,
                                    int *defaultp)
{
    const char *var = getenv (envname);
    if (!var) {
        *defaultp = 1;
        return defval;
    }
    return audio_string_to_audfmt (var, defval, defaultp);
}

static int audio_get_conf_int (const char *key, int defval, int *defaultp)
{
    int val;
    char *strval;

    strval = getenv (key);
    if (strval) {
        *defaultp = 0;
        val = atoi (strval);
        return val;
    }
    else {
        *defaultp = 1;
        return defval;
    }
}

static const char *audio_get_conf_str (const char *key,
                                       const char *defval,
                                       int *defaultp)
{
    const char *val = getenv (key);
    if (!val) {
        *defaultp = 1;
        return defval;
    }
    else {
        *defaultp = 0;
        return val;
    }
}

void AUD_vlog (const char *cap, const char *fmt, va_list ap)
{
    if (conf.log_to_monitor) {
        if (cap) {
            term_printf ("%s: ", cap);
        }

        term_vprintf (fmt, ap);
    }
    else {
        if (cap) {
            fprintf (stderr, "%s: ", cap);
        }

        vfprintf (stderr, fmt, ap);
    }
}

void AUD_log (const char *cap, const char *fmt, ...)
{
    va_list ap;

    va_start (ap, fmt);
    AUD_vlog (cap, fmt, ap);
    va_end (ap);
}

static void audio_print_options (const char *prefix,
                                 struct audio_option *opt)
{
    char *uprefix;

    if (!prefix) {
        dolog ("No prefix specified\n");
        return;
    }

    if (!opt) {
        dolog ("No options\n");
        return;
    }

    uprefix = audio_alloc_prefix (prefix);

    for (; opt->name; opt++) {
        const char *state = "default";
        printf ("  %s_%s: ", uprefix, opt->name);

        if (opt->overridenp && *opt->overridenp) {
            state = "current";
        }

        switch (opt->tag) {
        case AUD_OPT_BOOL:
            {
                int *intp = opt->valp;
                printf ("boolean, %s = %d\n", state, *intp ? 1 : 0);
            }
            break;

        case AUD_OPT_INT:
            {
                int *intp = opt->valp;
                printf ("integer, %s = %d\n", state, *intp);
            }
            break;

        case AUD_OPT_FMT:
            {
                audfmt_e *fmtp = opt->valp;
                printf (
                    "format, %s = %s, (one of: U8 S8 U16 S16)\n",
                    state,
                    audio_audfmt_to_string (*fmtp)
                    );
            }
            break;

        case AUD_OPT_STR:
            {
                const char **strp = opt->valp;
                printf ("string, %s = %s\n",
                        state,
                        *strp ? *strp : "(not set)");
            }
            break;

        default:
            printf ("???\n");
            dolog ("Bad value tag for option %s_%s %d\n",
                   uprefix, opt->name, opt->tag);
            break;
        }
        printf ("    %s\n", opt->descr);
    }

    qemu_free (uprefix);
}

static void audio_process_options (const char *prefix,
                                   struct audio_option *opt)
{
    char *optname;
    const char qemu_prefix[] = "QEMU_";
    size_t preflen;

    if (audio_bug (AUDIO_FUNC, !prefix)) {
        dolog ("prefix = NULL\n");
        return;
    }

    if (audio_bug (AUDIO_FUNC, !opt)) {
        dolog ("opt = NULL\n");
        return;
    }

    preflen = strlen (prefix);

    for (; opt->name; opt++) {
        size_t len, i;
        int def;

        if (!opt->valp) {
            dolog ("Option value pointer for `%s' is not set\n",
                   opt->name);
            continue;
        }

        len = strlen (opt->name);
        /* len of opt->name + len of prefix + size of qemu_prefix
         * (includes trailing zero) + zero + underscore (on behalf of
         * sizeof) */
        optname = qemu_malloc (len + preflen + sizeof (qemu_prefix) + 1);
        if (!optname) {
            dolog ("Could not allocate memory for option name `%s'\n",
                   opt->name);
            continue;
        }

        strcpy (optname, qemu_prefix);

        /* copy while upper-casing, including trailing zero */
        for (i = 0; i <= preflen; ++i) {
            optname[i + sizeof (qemu_prefix) - 1] = toupper ((uint8_t)prefix[i]);
        }
        strcat (optname, "_");
        strcat (optname, opt->name);

        def = 1;
        switch (opt->tag) {
        case AUD_OPT_BOOL:
        case AUD_OPT_INT:
            {
                int *intp = opt->valp;
                *intp = audio_get_conf_int (optname, *intp, &def);
            }
            break;

        case AUD_OPT_FMT:
            {
                audfmt_e *fmtp = opt->valp;
                *fmtp = audio_get_conf_fmt (optname, *fmtp, &def);
            }