qemu/audio/ossaudio.c
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   1/*
   2 * QEMU OSS audio driver
   3 *
   4 * Copyright (c) 2003-2005 Vassili Karpov (malc)
   5 *
   6 * Permission is hereby granted, free of charge, to any person obtaining a copy
   7 * of this software and associated documentation files (the "Software"), to deal
   8 * in the Software without restriction, including without limitation the rights
   9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10 * copies of the Software, and to permit persons to whom the Software is
  11 * furnished to do so, subject to the following conditions:
  12 *
  13 * The above copyright notice and this permission notice shall be included in
  14 * all copies or substantial portions of the Software.
  15 *
  16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22 * THE SOFTWARE.
  23 */
  24
  25#include "qemu/osdep.h"
  26#include <sys/ioctl.h>
  27#include <sys/soundcard.h>
  28#include "qemu/main-loop.h"
  29#include "qemu/module.h"
  30#include "qemu/host-utils.h"
  31#include "audio.h"
  32#include "trace.h"
  33
  34#define AUDIO_CAP "oss"
  35#include "audio_int.h"
  36
  37#if defined OSS_GETVERSION && defined SNDCTL_DSP_POLICY
  38#define USE_DSP_POLICY
  39#endif
  40
  41typedef struct OSSVoiceOut {
  42    HWVoiceOut hw;
  43    int fd;
  44    int nfrags;
  45    int fragsize;
  46    int mmapped;
  47    Audiodev *dev;
  48} OSSVoiceOut;
  49
  50typedef struct OSSVoiceIn {
  51    HWVoiceIn hw;
  52    int fd;
  53    int nfrags;
  54    int fragsize;
  55    Audiodev *dev;
  56} OSSVoiceIn;
  57
  58struct oss_params {
  59    int freq;
  60    int fmt;
  61    int nchannels;
  62    int nfrags;
  63    int fragsize;
  64};
  65
  66static void GCC_FMT_ATTR (2, 3) oss_logerr (int err, const char *fmt, ...)
  67{
  68    va_list ap;
  69
  70    va_start (ap, fmt);
  71    AUD_vlog (AUDIO_CAP, fmt, ap);
  72    va_end (ap);
  73
  74    AUD_log (AUDIO_CAP, "Reason: %s\n", strerror (err));
  75}
  76
  77static void GCC_FMT_ATTR (3, 4) oss_logerr2 (
  78    int err,
  79    const char *typ,
  80    const char *fmt,
  81    ...
  82    )
  83{
  84    va_list ap;
  85
  86    AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
  87
  88    va_start (ap, fmt);
  89    AUD_vlog (AUDIO_CAP, fmt, ap);
  90    va_end (ap);
  91
  92    AUD_log (AUDIO_CAP, "Reason: %s\n", strerror (err));
  93}
  94
  95static void oss_anal_close (int *fdp)
  96{
  97    int err;
  98
  99    qemu_set_fd_handler (*fdp, NULL, NULL, NULL);
 100    err = close (*fdp);
 101    if (err) {
 102        oss_logerr (errno, "Failed to close file(fd=%d)\n", *fdp);
 103    }
 104    *fdp = -1;
 105}
 106
 107static void oss_helper_poll_out (void *opaque)
 108{
 109    AudioState *s = opaque;
 110    audio_run(s, "oss_poll_out");
 111}
 112
 113static void oss_helper_poll_in (void *opaque)
 114{
 115    AudioState *s = opaque;
 116    audio_run(s, "oss_poll_in");
 117}
 118
 119static void oss_poll_out (HWVoiceOut *hw)
 120{
 121    OSSVoiceOut *oss = (OSSVoiceOut *) hw;
 122
 123    qemu_set_fd_handler(oss->fd, NULL, oss_helper_poll_out, hw->s);
 124}
 125
 126static void oss_poll_in (HWVoiceIn *hw)
 127{
 128    OSSVoiceIn *oss = (OSSVoiceIn *) hw;
 129
 130    qemu_set_fd_handler(oss->fd, oss_helper_poll_in, NULL, hw->s);
 131}
 132
 133static int aud_to_ossfmt (AudioFormat fmt, int endianness)
 134{
 135    switch (fmt) {
 136    case AUDIO_FORMAT_S8:
 137        return AFMT_S8;
 138
 139    case AUDIO_FORMAT_U8:
 140        return AFMT_U8;
 141
 142    case AUDIO_FORMAT_S16:
 143        if (endianness) {
 144            return AFMT_S16_BE;
 145        } else {
 146            return AFMT_S16_LE;
 147        }
 148
 149    case AUDIO_FORMAT_U16:
 150        if (endianness) {
 151            return AFMT_U16_BE;
 152        } else {
 153            return AFMT_U16_LE;
 154        }
 155
 156    default:
 157        dolog ("Internal logic error: Bad audio format %d\n", fmt);
 158#ifdef DEBUG_AUDIO
 159        abort ();
 160#endif
 161        return AFMT_U8;
 162    }
 163}
 164
 165static int oss_to_audfmt (int ossfmt, AudioFormat *fmt, int *endianness)
 166{
 167    switch (ossfmt) {
 168    case AFMT_S8:
 169        *endianness = 0;
 170        *fmt = AUDIO_FORMAT_S8;
 171        break;
 172
 173    case AFMT_U8:
 174        *endianness = 0;
 175        *fmt = AUDIO_FORMAT_U8;
 176        break;
 177
 178    case AFMT_S16_LE:
 179        *endianness = 0;
 180        *fmt = AUDIO_FORMAT_S16;
 181        break;
 182
 183    case AFMT_U16_LE:
 184        *endianness = 0;
 185        *fmt = AUDIO_FORMAT_U16;
 186        break;
 187
 188    case AFMT_S16_BE:
 189        *endianness = 1;
 190        *fmt = AUDIO_FORMAT_S16;
 191        break;
 192
 193    case AFMT_U16_BE:
 194        *endianness = 1;
 195        *fmt = AUDIO_FORMAT_U16;
 196        break;
 197
 198    default:
 199        dolog ("Unrecognized audio format %d\n", ossfmt);
 200        return -1;
 201    }
 202
 203    return 0;
 204}
 205
 206#if defined DEBUG_MISMATCHES || defined DEBUG
 207static void oss_dump_info (struct oss_params *req, struct oss_params *obt)
 208{
 209    dolog ("parameter | requested value | obtained value\n");
 210    dolog ("format    |      %10d |     %10d\n", req->fmt, obt->fmt);
 211    dolog ("channels  |      %10d |     %10d\n",
 212           req->nchannels, obt->nchannels);
 213    dolog ("frequency |      %10d |     %10d\n", req->freq, obt->freq);
 214    dolog ("nfrags    |      %10d |     %10d\n", req->nfrags, obt->nfrags);
 215    dolog ("fragsize  |      %10d |     %10d\n",
 216           req->fragsize, obt->fragsize);
 217}
 218#endif
 219
 220#ifdef USE_DSP_POLICY
 221static int oss_get_version (int fd, int *version, const char *typ)
 222{
 223    if (ioctl (fd, OSS_GETVERSION, &version)) {
 224#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 225        /*
 226         * Looks like atm (20100109) FreeBSD knows OSS_GETVERSION
 227         * since 7.x, but currently only on the mixer device (or in
 228         * the Linuxolator), and in the native version that part of
 229         * the code is in fact never reached so the ioctl fails anyway.
 230         * Until this is fixed, just check the errno and if its what
 231         * FreeBSD's sound drivers return atm assume they are new enough.
 232         */
 233        if (errno == EINVAL) {
 234            *version = 0x040000;
 235            return 0;
 236        }
 237#endif
 238        oss_logerr2 (errno, typ, "Failed to get OSS version\n");
 239        return -1;
 240    }
 241    return 0;
 242}
 243#endif
 244
 245static int oss_open(int in, struct oss_params *req, audsettings *as,
 246                    struct oss_params *obt, int *pfd, Audiodev *dev)
 247{
 248    AudiodevOssOptions *oopts = &dev->u.oss;
 249    AudiodevOssPerDirectionOptions *opdo = in ? oopts->in : oopts->out;
 250    int fd;
 251    int oflags = (oopts->has_exclusive && oopts->exclusive) ? O_EXCL : 0;
 252    audio_buf_info abinfo;
 253    int fmt, freq, nchannels;
 254    int setfragment = 1;
 255    const char *dspname = opdo->has_dev ? opdo->dev : "/dev/dsp";
 256    const char *typ = in ? "ADC" : "DAC";
 257#ifdef USE_DSP_POLICY
 258    int policy = oopts->has_dsp_policy ? oopts->dsp_policy : 5;
 259#endif
 260
 261    /* Kludge needed to have working mmap on Linux */
 262    oflags |= (oopts->has_try_mmap && oopts->try_mmap) ?
 263        O_RDWR : (in ? O_RDONLY : O_WRONLY);
 264
 265    fd = open (dspname, oflags | O_NONBLOCK);
 266    if (-1 == fd) {
 267        oss_logerr2 (errno, typ, "Failed to open `%s'\n", dspname);
 268        return -1;
 269    }
 270
 271    freq = req->freq;
 272    nchannels = req->nchannels;
 273    fmt = req->fmt;
 274    req->nfrags = opdo->has_buffer_count ? opdo->buffer_count : 4;
 275    req->fragsize = audio_buffer_bytes(
 276        qapi_AudiodevOssPerDirectionOptions_base(opdo), as, 23220);
 277
 278    if (ioctl (fd, SNDCTL_DSP_SAMPLESIZE, &fmt)) {
 279        oss_logerr2 (errno, typ, "Failed to set sample size %d\n", req->fmt);
 280        goto err;
 281    }
 282
 283    if (ioctl (fd, SNDCTL_DSP_CHANNELS, &nchannels)) {
 284        oss_logerr2 (errno, typ, "Failed to set number of channels %d\n",
 285                     req->nchannels);
 286        goto err;
 287    }
 288
 289    if (ioctl (fd, SNDCTL_DSP_SPEED, &freq)) {
 290        oss_logerr2 (errno, typ, "Failed to set frequency %d\n", req->freq);
 291        goto err;
 292    }
 293
 294    if (ioctl (fd, SNDCTL_DSP_NONBLOCK, NULL)) {
 295        oss_logerr2 (errno, typ, "Failed to set non-blocking mode\n");
 296        goto err;
 297    }
 298
 299#ifdef USE_DSP_POLICY
 300    if (policy >= 0) {
 301        int version;
 302
 303        if (!oss_get_version (fd, &version, typ)) {
 304            trace_oss_version(version);
 305
 306            if (version >= 0x040000) {
 307                int policy2 = policy;
 308                if (ioctl(fd, SNDCTL_DSP_POLICY, &policy2)) {
 309                    oss_logerr2 (errno, typ,
 310                                 "Failed to set timing policy to %d\n",
 311                                 policy);
 312                    goto err;
 313                }
 314                setfragment = 0;
 315            }
 316        }
 317    }
 318#endif
 319
 320    if (setfragment) {
 321        int mmmmssss = (req->nfrags << 16) | ctz32 (req->fragsize);
 322        if (ioctl (fd, SNDCTL_DSP_SETFRAGMENT, &mmmmssss)) {
 323            oss_logerr2 (errno, typ, "Failed to set buffer length (%d, %d)\n",
 324                         req->nfrags, req->fragsize);
 325            goto err;
 326        }
 327    }
 328
 329    if (ioctl (fd, in ? SNDCTL_DSP_GETISPACE : SNDCTL_DSP_GETOSPACE, &abinfo)) {
 330        oss_logerr2 (errno, typ, "Failed to get buffer length\n");
 331        goto err;
 332    }
 333
 334    if (!abinfo.fragstotal || !abinfo.fragsize) {
 335        AUD_log (AUDIO_CAP, "Returned bogus buffer information(%d, %d) for %s\n",
 336                 abinfo.fragstotal, abinfo.fragsize, typ);
 337        goto err;
 338    }
 339
 340    obt->fmt = fmt;
 341    obt->nchannels = nchannels;
 342    obt->freq = freq;
 343    obt->nfrags = abinfo.fragstotal;
 344    obt->fragsize = abinfo.fragsize;
 345    *pfd = fd;
 346
 347#ifdef DEBUG_MISMATCHES
 348    if ((req->fmt != obt->fmt) ||
 349        (req->nchannels != obt->nchannels) ||
 350        (req->freq != obt->freq) ||
 351        (req->fragsize != obt->fragsize) ||
 352        (req->nfrags != obt->nfrags)) {
 353        dolog ("Audio parameters mismatch\n");
 354        oss_dump_info (req, obt);
 355    }
 356#endif
 357
 358#ifdef DEBUG
 359    oss_dump_info (req, obt);
 360#endif
 361    return 0;
 362
 363 err:
 364    oss_anal_close (&fd);
 365    return -1;
 366}
 367
 368static size_t oss_get_available_bytes(OSSVoiceOut *oss)
 369{
 370    int err;
 371    struct count_info cntinfo;
 372    assert(oss->mmapped);
 373
 374    err = ioctl(oss->fd, SNDCTL_DSP_GETOPTR, &cntinfo);
 375    if (err < 0) {
 376        oss_logerr(errno, "SNDCTL_DSP_GETOPTR failed\n");
 377        return 0;
 378    }
 379
 380    return audio_ring_dist(cntinfo.ptr, oss->hw.pos_emul, oss->hw.size_emul);
 381}
 382
 383static void oss_run_buffer_out(HWVoiceOut *hw)
 384{
 385    OSSVoiceOut *oss = (OSSVoiceOut *)hw;
 386
 387    if (!oss->mmapped) {
 388        audio_generic_run_buffer_out(hw);
 389    }
 390}
 391
 392static void *oss_get_buffer_out(HWVoiceOut *hw, size_t *size)
 393{
 394    OSSVoiceOut *oss = (OSSVoiceOut *) hw;
 395    if (oss->mmapped) {
 396        *size = MIN(oss_get_available_bytes(oss), hw->size_emul - hw->pos_emul);
 397        return hw->buf_emul + hw->pos_emul;
 398    } else {
 399        return audio_generic_get_buffer_out(hw, size);
 400    }
 401}
 402
 403static size_t oss_put_buffer_out(HWVoiceOut *hw, void *buf, size_t size)
 404{
 405    OSSVoiceOut *oss = (OSSVoiceOut *) hw;
 406    if (oss->mmapped) {
 407        assert(buf == hw->buf_emul + hw->pos_emul && size < hw->size_emul);
 408
 409        hw->pos_emul = (hw->pos_emul + size) % hw->size_emul;
 410        return size;
 411    } else {
 412        return audio_generic_put_buffer_out(hw, buf, size);
 413    }
 414}
 415
 416static size_t oss_write(HWVoiceOut *hw, void *buf, size_t len)
 417{
 418    OSSVoiceOut *oss = (OSSVoiceOut *) hw;
 419    size_t pos;
 420
 421    if (oss->mmapped) {
 422        size_t total_len;
 423        len = MIN(len, oss_get_available_bytes(oss));
 424
 425        total_len = len;
 426        while (len) {
 427            size_t to_copy = MIN(len, hw->size_emul - hw->pos_emul);
 428            memcpy(hw->buf_emul + hw->pos_emul, buf, to_copy);
 429
 430            hw->pos_emul = (hw->pos_emul + to_copy) % hw->size_emul;
 431            buf += to_copy;
 432            len -= to_copy;
 433        }
 434        return total_len;
 435    }
 436
 437    pos = 0;
 438    while (len) {
 439        ssize_t bytes_written;
 440        void *pcm = advance(buf, pos);
 441
 442        bytes_written = write(oss->fd, pcm, len);
 443        if (bytes_written < 0) {
 444            if (errno != EAGAIN) {
 445                oss_logerr(errno, "failed to write %zu bytes\n",
 446                           len);
 447            }
 448            return pos;
 449        }
 450
 451        pos += bytes_written;
 452        if (bytes_written < len) {
 453            break;
 454        }
 455        len -= bytes_written;
 456    }
 457    return pos;
 458}
 459
 460static void oss_fini_out (HWVoiceOut *hw)
 461{
 462    int err;
 463    OSSVoiceOut *oss = (OSSVoiceOut *) hw;
 464
 465    ldebug ("oss_fini\n");
 466    oss_anal_close (&oss->fd);
 467
 468    if (oss->mmapped && hw->buf_emul) {
 469        err = munmap(hw->buf_emul, hw->size_emul);
 470        if (err) {
 471            oss_logerr(errno, "Failed to unmap buffer %p, size %zu\n",
 472                       hw->buf_emul, hw->size_emul);
 473        }
 474        hw->buf_emul = NULL;
 475    }
 476}
 477
 478static int oss_init_out(HWVoiceOut *hw, struct audsettings *as,
 479                        void *drv_opaque)
 480{
 481    OSSVoiceOut *oss = (OSSVoiceOut *) hw;
 482    struct oss_params req, obt;
 483    int endianness;
 484    int err;
 485    int fd;
 486    AudioFormat effective_fmt;
 487    struct audsettings obt_as;
 488    Audiodev *dev = drv_opaque;
 489    AudiodevOssOptions *oopts = &dev->u.oss;
 490
 491    oss->fd = -1;
 492
 493    req.fmt = aud_to_ossfmt (as->fmt, as->endianness);
 494    req.freq = as->freq;
 495    req.nchannels = as->nchannels;
 496
 497    if (oss_open(0, &req, as, &obt, &fd, dev)) {
 498        return -1;
 499    }
 500
 501    err = oss_to_audfmt (obt.fmt, &effective_fmt, &endianness);
 502    if (err) {
 503        oss_anal_close (&fd);
 504        return -1;
 505    }
 506
 507    obt_as.freq = obt.freq;
 508    obt_as.nchannels = obt.nchannels;
 509    obt_as.fmt = effective_fmt;
 510    obt_as.endianness = endianness;
 511
 512    audio_pcm_init_info (&hw->info, &obt_as);
 513    oss->nfrags = obt.nfrags;
 514    oss->fragsize = obt.fragsize;
 515
 516    if (obt.nfrags * obt.fragsize % hw->info.bytes_per_frame) {
 517        dolog ("warning: Misaligned DAC buffer, size %d, alignment %d\n",
 518               obt.nfrags * obt.fragsize, hw->info.bytes_per_frame);
 519    }
 520
 521    hw->samples = (obt.nfrags * obt.fragsize) / hw->info.bytes_per_frame;
 522
 523    oss->mmapped = 0;
 524    if (oopts->has_try_mmap && oopts->try_mmap) {
 525        hw->size_emul = hw->samples * hw->info.bytes_per_frame;
 526        hw->buf_emul = mmap(
 527            NULL,
 528            hw->size_emul,
 529            PROT_READ | PROT_WRITE,
 530            MAP_SHARED,
 531            fd,
 532            0
 533            );
 534        if (hw->buf_emul == MAP_FAILED) {
 535            oss_logerr(errno, "Failed to map %zu bytes of DAC\n",
 536                       hw->size_emul);
 537            hw->buf_emul = NULL;
 538        } else {
 539            int err;
 540            int trig = 0;
 541            if (ioctl (fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
 542                oss_logerr (errno, "SNDCTL_DSP_SETTRIGGER 0 failed\n");
 543            } else {
 544                trig = PCM_ENABLE_OUTPUT;
 545                if (ioctl (fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
 546                    oss_logerr (
 547                        errno,
 548                        "SNDCTL_DSP_SETTRIGGER PCM_ENABLE_OUTPUT failed\n"
 549                        );
 550                } else {
 551                    oss->mmapped = 1;
 552                }
 553            }
 554
 555            if (!oss->mmapped) {
 556                err = munmap(hw->buf_emul, hw->size_emul);
 557                if (err) {
 558                    oss_logerr(errno, "Failed to unmap buffer %p size %zu\n",
 559                               hw->buf_emul, hw->size_emul);
 560                }
 561                hw->buf_emul = NULL;
 562            }
 563        }
 564    }
 565
 566    oss->fd = fd;
 567    oss->dev = dev;
 568    return 0;
 569}
 570
 571static void oss_enable_out(HWVoiceOut *hw, bool enable)
 572{
 573    int trig;
 574    OSSVoiceOut *oss = (OSSVoiceOut *) hw;
 575    AudiodevOssPerDirectionOptions *opdo = oss->dev->u.oss.out;
 576
 577    if (enable) {
 578        hw->poll_mode = opdo->try_poll;
 579
 580        ldebug("enabling voice\n");
 581        if (hw->poll_mode) {
 582            oss_poll_out(hw);
 583        }
 584
 585        if (!oss->mmapped) {
 586            return;
 587        }
 588
 589        audio_pcm_info_clear_buf(&hw->info, hw->buf_emul, hw->samples);
 590        trig = PCM_ENABLE_OUTPUT;
 591        if (ioctl(oss->fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
 592            oss_logerr(errno,
 593                       "SNDCTL_DSP_SETTRIGGER PCM_ENABLE_OUTPUT failed\n");
 594            return;
 595        }
 596    } else {
 597        if (hw->poll_mode) {
 598            qemu_set_fd_handler (oss->fd, NULL, NULL, NULL);
 599            hw->poll_mode = 0;
 600        }
 601
 602        if (!oss->mmapped) {
 603            return;
 604        }
 605
 606        ldebug ("disabling voice\n");
 607        trig = 0;
 608        if (ioctl (oss->fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
 609            oss_logerr (errno, "SNDCTL_DSP_SETTRIGGER 0 failed\n");
 610            return;
 611        }
 612    }
 613}
 614
 615static int oss_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
 616{
 617    OSSVoiceIn *oss = (OSSVoiceIn *) hw;
 618    struct oss_params req, obt;
 619    int endianness;
 620    int err;
 621    int fd;
 622    AudioFormat effective_fmt;
 623    struct audsettings obt_as;
 624    Audiodev *dev = drv_opaque;
 625
 626    oss->fd = -1;
 627
 628    req.fmt = aud_to_ossfmt (as->fmt, as->endianness);
 629    req.freq = as->freq;
 630    req.nchannels = as->nchannels;
 631    if (oss_open(1, &req, as, &obt, &fd, dev)) {
 632        return -1;
 633    }
 634
 635    err = oss_to_audfmt (obt.fmt, &effective_fmt, &endianness);
 636    if (err) {
 637        oss_anal_close (&fd);
 638        return -1;
 639    }
 640
 641    obt_as.freq = obt.freq;
 642    obt_as.nchannels = obt.nchannels;
 643    obt_as.fmt = effective_fmt;
 644    obt_as.endianness = endianness;
 645
 646    audio_pcm_init_info (&hw->info, &obt_as);
 647    oss->nfrags = obt.nfrags;
 648    oss->fragsize = obt.fragsize;
 649
 650    if (obt.nfrags * obt.fragsize % hw->info.bytes_per_frame) {
 651        dolog ("warning: Misaligned ADC buffer, size %d, alignment %d\n",
 652               obt.nfrags * obt.fragsize, hw->info.bytes_per_frame);
 653    }
 654
 655    hw->samples = (obt.nfrags * obt.fragsize) / hw->info.bytes_per_frame;
 656
 657    oss->fd = fd;
 658    oss->dev = dev;
 659    return 0;
 660}
 661
 662static void oss_fini_in (HWVoiceIn *hw)
 663{
 664    OSSVoiceIn *oss = (OSSVoiceIn *) hw;
 665
 666    oss_anal_close (&oss->fd);
 667}
 668
 669static size_t oss_read(HWVoiceIn *hw, void *buf, size_t len)
 670{
 671    OSSVoiceIn *oss = (OSSVoiceIn *) hw;
 672    size_t pos = 0;
 673
 674    while (len) {
 675        ssize_t nread;
 676
 677        void *dst = advance(buf, pos);
 678        nread = read(oss->fd, dst, len);
 679
 680        if (nread == -1) {
 681            switch (errno) {
 682            case EINTR:
 683            case EAGAIN:
 684                break;
 685            default:
 686                oss_logerr(errno, "Failed to read %zu bytes of audio (to %p)\n",
 687                           len, dst);
 688                break;
 689            }
 690            break;
 691        }
 692
 693        pos += nread;
 694        len -= nread;
 695    }
 696
 697    return pos;
 698}
 699
 700static void oss_enable_in(HWVoiceIn *hw, bool enable)
 701{
 702    OSSVoiceIn *oss = (OSSVoiceIn *) hw;
 703    AudiodevOssPerDirectionOptions *opdo = oss->dev->u.oss.out;
 704
 705    if (enable) {
 706        hw->poll_mode = opdo->try_poll;
 707
 708        if (hw->poll_mode) {
 709            oss_poll_in(hw);
 710        }
 711    } else {
 712        if (hw->poll_mode) {
 713            qemu_set_fd_handler (oss->fd, NULL, NULL, NULL);
 714            hw->poll_mode = 0;
 715        }
 716    }
 717}
 718
 719static void oss_init_per_direction(AudiodevOssPerDirectionOptions *opdo)
 720{
 721    if (!opdo->has_try_poll) {
 722        opdo->try_poll = true;
 723        opdo->has_try_poll = true;
 724    }
 725}
 726
 727static void *oss_audio_init(Audiodev *dev)
 728{
 729    AudiodevOssOptions *oopts;
 730    assert(dev->driver == AUDIODEV_DRIVER_OSS);
 731
 732    oopts = &dev->u.oss;
 733    oss_init_per_direction(oopts->in);
 734    oss_init_per_direction(oopts->out);
 735
 736    if (access(oopts->in->has_dev ? oopts->in->dev : "/dev/dsp",
 737               R_OK | W_OK) < 0 ||
 738        access(oopts->out->has_dev ? oopts->out->dev : "/dev/dsp",
 739               R_OK | W_OK) < 0) {
 740        return NULL;
 741    }
 742    return dev;
 743}
 744
 745static void oss_audio_fini (void *opaque)
 746{
 747}
 748
 749static struct audio_pcm_ops oss_pcm_ops = {
 750    .init_out = oss_init_out,
 751    .fini_out = oss_fini_out,
 752    .write    = oss_write,
 753    .run_buffer_out = oss_run_buffer_out,
 754    .get_buffer_out = oss_get_buffer_out,
 755    .put_buffer_out = oss_put_buffer_out,
 756    .enable_out = oss_enable_out,
 757
 758    .init_in  = oss_init_in,
 759    .fini_in  = oss_fini_in,
 760    .read     = oss_read,
 761    .run_buffer_in = audio_generic_run_buffer_in,
 762    .enable_in = oss_enable_in
 763};
 764
 765static struct audio_driver oss_audio_driver = {
 766    .name           = "oss",
 767    .descr          = "OSS http://www.opensound.com",
 768    .init           = oss_audio_init,
 769    .fini           = oss_audio_fini,
 770    .pcm_ops        = &oss_pcm_ops,
 771    .can_be_default = 1,
 772    .max_voices_out = INT_MAX,
 773    .max_voices_in  = INT_MAX,
 774    .voice_size_out = sizeof (OSSVoiceOut),
 775    .voice_size_in  = sizeof (OSSVoiceIn)
 776};
 777
 778static void register_audio_oss(void)
 779{
 780    audio_driver_register(&oss_audio_driver);
 781}
 782type_init(register_audio_oss);
 783