SDL Audio support and SB16 fixes (malc)

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1108 c046a42c-6fe2-441c-8c8c-71466251a162

3 files changed, 860 insertions, 233 deletions

diff --git a/Changelog b/Changelog
index 5117b243e3..73b85e5dd6 100644
--- a/Changelog
+++ b/Changelog
@@ -26,6 +26,7 @@ version 0.6.1:
   - BIOS floppy fix for NT4 (Mike Nordell, Derek Fawcus, Volker Ruppert)
   - Floppy fixes for NT4 and NT5 (Mike Nordell)
   - NT4 IDE fixes (Ben Pfaf, Mike Nordell)
+  - SDL Audio support and SB16 fixes (malc)
 
 version 0.6.0:
 
diff --git a/hw/sb16.c b/hw/sb16.c
index 260718cdc0..f84cf8d4a2 100644
--- a/hw/sb16.c
+++ b/hw/sb16.c
@@ -26,12 +26,10 @@
 #define MIN(a, b) ((a)>(b)?(b):(a))
 #define LENOFA(a) ((int) (sizeof(a)/sizeof(a[0])))
 
-#define log(...) do {                           \
-    fprintf (stderr, "sb16: " __VA_ARGS__);     \
-    fputc ('\n', stderr);                       \
-} while (0)
+#define dolog(...) fprintf (stderr, "sb16: " __VA_ARGS__);
 
 /* #define DEBUG_SB16 */
+
 #ifdef DEBUG_SB16
 #define lwarn(...) fprintf (stderr, "sb16: " __VA_ARGS__)
 #define linfo(...) fprintf (stderr, "sb16: " __VA_ARGS__)
@@ -47,7 +45,10 @@
 #define IO_WRITE_PROTO(name) \
     void name (void *opaque, uint32_t nport, uint32_t val)
 
-static const char e3[] = "COPYRIGHT (C) CREATIVE TECHNOLOGY LTD, 1992.";
+static const char e3[] =
+    "COPYRIGHT (C) CREATIVE TECHNOLOGY LTD, 1992\0"
+    "COPYRIGHT (C) CREATIVE TECHNOLOGY LTD, 1994-1997";
+    /* "COPYRIGHT (C) CREATIVE TECHNOLOGY LTD, 1994."; */
 
 static struct {
     int ver_lo;
@@ -80,10 +81,13 @@ typedef struct SB16State {
 
     int v2x6;
 
-    uint8_t in_data[10];
-    uint8_t out_data[50];
+    uint8_t in2_data[10];
+    uint8_t out_data[1024];
 
     int left_till_irq;
+    uint64_t nzero;
+    uint8_t last_read_byte;
+    uint8_t test_reg;
 
     /* mixer state */
     int mixer_nreg;
@@ -95,7 +99,7 @@ static struct SB16State dsp;
 
 static void log_dsp (SB16State *dsp)
 {
-    linfo ("%c:%c:%d:%c:dmabuf=%d:pos=%d:freq=%d:timeconst=%d:speaker=%d\n",
+    ldebug ("%c:%c:%d:%c:dmabuf=%d:pos=%d:freq=%d:timeconst=%d:speaker=%d\n",
            dsp->fmt_stereo ? 'S' : 'M',
            dsp->fmt_signed ? 'S' : 'U',
            dsp->fmt_bits,
@@ -191,6 +195,7 @@ static void dma_cmd (uint8_t cmd, uint8_t d0, int dma_len)
         mix_block = ((dsp.freq * align) / 100) & ~(align - 1);
     }
 
+    if (dsp.freq)
     AUD_reset (dsp.freq, 1 << dsp.fmt_stereo, fmt);
     control (1);
     dsp.speaker = 1;
@@ -202,9 +207,17 @@ static inline void dsp_out_data(SB16State *dsp, int val)
         dsp->out_data[dsp->out_data_len++] = val;
 }
 
+static inline uint8_t dsp_get_data(SB16State *dsp)
+{
+    if (dsp->in_index)
+        return dsp->in2_data[--dsp->in_index];
+    else
+        return 0;
+}
+
 static void command (SB16State *dsp, uint8_t cmd)
 {
-    linfo ("%#x\n", cmd);
+    linfo ("command: %#x\n", cmd);
 
     if (cmd > 0xaf && cmd < 0xd0) {
         if (cmd & 8)
@@ -215,7 +228,7 @@ static void command (SB16State *dsp, uint8_t cmd)
         case 12:
             break;
         default:
-            log("%#x wrong bits", cmd);
+            dolog ("command: %#x wrong bits specification\n", cmd);
             goto error;
         }
         dsp->needed_bytes = 3;
@@ -223,23 +236,25 @@ static void command (SB16State *dsp, uint8_t cmd)
     else {
         switch (cmd) {
         case 0x00:
-        case 0x03:
         case 0xe7:
             /* IMS uses those when probing for sound devices */
             return;
 
+        case 0x03:
         case 0x04:
-            dsp->needed_bytes = 1;
-            break;
+            dsp_out_data (dsp, 0);
+            return;
 
         case 0x05:
+            dsp->needed_bytes = 2;
+            break;
+
         case 0x0e:
             dsp->needed_bytes = 2;
             break;
 
         case 0x0f:
             dsp->needed_bytes = 1;
-            dsp_out_data (dsp, 0);
             break;
 
         case 0x10:
@@ -272,6 +287,8 @@ static void command (SB16State *dsp, uint8_t cmd)
             dsp->needed_bytes = 2;
             break;
 
+        case 0x45:
+            dsp_out_data (dsp, 0xaa);
         case 0x47:                /* Continue Auto-Initialize DMA 16bit */
             break;
 
@@ -346,19 +363,39 @@ static void command (SB16State *dsp, uint8_t cmd)
         case 0xe3:
             {
                 int i;
-                for (i = sizeof (e3) - 1; i >= 0; --i)
+                for (i = sizeof (e3) - 1; i >= 0; i--)
                     dsp_out_data (dsp, e3[i]);
                 return;
             }
 
+        case 0xe4:              /* write test reg */
+            dsp->needed_bytes = 1;
+            break;
+
+        case 0xe8:              /* read test reg */
+            dsp_out_data (dsp, dsp->test_reg);
+            break;
+
         case 0xf2:
-            dsp_out_data(dsp, 0xaa);
+            dsp_out_data (dsp, 0xaa);
             dsp->mixer_regs[0x82] |= dsp->mixer_regs[0x80];
             pic_set_irq (sb.irq, 1);
             return;
 
+        case 0xf9:
+            dsp->needed_bytes = 1;
+            break;
+
+        case 0xfa:
+            dsp_out_data (dsp, 0);
+            break;
+
+        case 0xfc:              /* FIXME */
+            dsp_out_data (dsp, 0);
+            break;
+
         default:
-            log("%#x is unknown", cmd);
+            dolog ("unrecognized command %#x\n", cmd);
             goto error;
         }
     }
@@ -371,15 +408,14 @@ static void command (SB16State *dsp, uint8_t cmd)
 
 static void complete (SB16State *dsp)
 {
+    int d0, d1, d2;
     linfo ("complete command %#x, in_index %d, needed_bytes %d\n",
            dsp->cmd, dsp->in_index, dsp->needed_bytes);
 
     if (dsp->cmd > 0xaf && dsp->cmd < 0xd0) {
-        int d0, d1, d2;
-
-        d0 = dsp->in_data[0];
-        d1 = dsp->in_data[1];
-        d2 = dsp->in_data[2];
+        d2 = dsp_get_data (dsp);
+        d1 = dsp_get_data (dsp);
+        d0 = dsp_get_data (dsp);
 
         ldebug ("d0 = %d, d1 = %d, d2 = %d\n",
                 d0, d1, d2);
@@ -387,23 +423,29 @@ static void complete (SB16State *dsp)
     }
     else {
         switch (dsp->cmd) {
-        case 0x05:
         case 0x04:
-        case 0x0e:
+        case 0x10:
+            dsp_get_data (dsp);
+            break;
+
         case 0x0f:
+            d0 = dsp_get_data (dsp);
+            dsp_out_data (dsp, 0xf8);
             break;
 
-        case 0x10:
+        case 0x05:
+        case 0x0e:
+            dsp_get_data (dsp);
+            dsp_get_data (dsp);
             break;
 
         case 0x14:
             {
-                int d0, d1;
                 int save_left;
                 int save_pos;
 
-                d0 = dsp->in_data[0];
-                d1 = dsp->in_data[1];
+                d1 = dsp_get_data (dsp);
+                d0 = dsp_get_data (dsp);
 
                 save_left = dsp->left_till_irq;
                 save_pos = dsp->dma_pos;
@@ -417,35 +459,60 @@ static void complete (SB16State *dsp)
             }
 
         case 0x40:
-            dsp->time_const = dsp->in_data[0];
+            dsp->time_const = dsp_get_data (dsp);
             linfo ("set time const %d\n", dsp->time_const);
             break;
 
         case 0x41:
         case 0x42:
-            dsp->freq = dsp->in_data[1] + (dsp->in_data[0] << 8);
-            linfo ("set freq %#x, %#x = %d\n",
-                   dsp->in_data[1], dsp->in_data[0], dsp->freq);
+            d1 = dsp_get_data (dsp);
+            d0 = dsp_get_data (dsp);
+
+            dsp->freq = d1 + (d0 << 8);
+            linfo ("set freq %#x, %#x = %d\n", d1, d0, dsp->freq);
             break;
 
         case 0x48:
-            dsp->dma_buffer_size = dsp->in_data[1] + (dsp->in_data[0] << 8);
+            d1 = dsp_get_data (dsp);
+            d0 = dsp_get_data (dsp);
+            dsp->dma_buffer_size = d1 + (d0 << 8);
             linfo ("set dma len %#x, %#x = %d\n",
-                   dsp->in_data[1], dsp->in_data[0], dsp->dma_buffer_size);
+                   d1, d0, dsp->dma_buffer_size);
             break;
 
         case 0xe0:
+            d0 = dsp_get_data (dsp);
             dsp->out_data_len = 0;
-            linfo ("data = %#x\n", dsp->in_data[0]);
-            dsp_out_data(dsp, dsp->in_data[0] ^ 0xff);
+            linfo ("data = %#x\n", d0);
+            dsp_out_data (dsp, d0 ^ 0xff);
+            break;
+
+        case 0xe4:
+            dsp->test_reg = dsp_get_data (dsp);
+            break;
+
+
+        case 0xf9:
+            d0 = dsp_get_data (dsp);
+            ldebug ("f9 <- %#x\n", d0);
+            switch (d0) {
+            case 0x0e: dsp_out_data (dsp, 0xff); break;
+            case 0x0f: dsp_out_data (dsp, 0x07); break;
+            case 0xf9: dsp_out_data (dsp, 0x00); break;
+            case 0x37:
+                dsp_out_data (dsp, 0x38); break;
+            default:
+                dsp_out_data (dsp, 0);
+            }
             break;
 
         default:
-            log ("unrecognized command %#x", dsp->cmd);
+            dolog ("complete: unrecognized command %#x\n", dsp->cmd);
             return;
         }
     }
 
+    dsp->needed_bytes = 0;
     dsp->cmd = -1;
     return;
 }
@@ -457,7 +524,7 @@ static IO_WRITE_PROTO (dsp_write)
 
     iport = nport - sb.port;
 
-    ldebug ("write %#x %#x\n", nport, iport);
+    ldebug ("dsp_write %#x <- %#x\n", nport, val);
     switch (iport) {
     case 0x6:
         control (0);
@@ -465,6 +532,14 @@ static IO_WRITE_PROTO (dsp_write)
             dsp->v2x6 = 0;
         else if ((1 == val) && (0 == dsp->v2x6)) {
             dsp->v2x6 = 1;
+            dsp->dma_pos = 0;
+            dsp->dma_auto = 0;
+            dsp->in_index = 0;
+            dsp->out_data_len = 0;
+            dsp->left_till_irq = 0;
+            dsp->speaker = 0;
+            dsp->needed_bytes = 0;
+            pic_set_irq (sb.irq, 0);
             dsp_out_data(dsp, 0xaa);
         }
         else
@@ -479,18 +554,22 @@ static IO_WRITE_PROTO (dsp_write)
             }
         }
         else {
-            dsp->in_data[dsp->in_index++] = val;
+            if (dsp->in_index == sizeof (dsp->in2_data)) {
+                dolog ("in data overrun\n");
+            }
+            else {
+                dsp->in2_data[dsp->in_index++] = val;
             if (dsp->in_index == dsp->needed_bytes) {
                 dsp->needed_bytes = 0;
-                dsp->in_index = 0;
                 complete (dsp);
                 log_dsp (dsp);
             }
         }
+        }
         break;
 
     default:
-        log ("(nport=%#x, val=%#x)", nport, val);
+        dolog ("dsp_write (nport=%#x, val=%#x)\n", nport, val);
         break;
     }
 }
@@ -503,31 +582,36 @@ static IO_READ_PROTO (dsp_read)
     iport = nport - sb.port;
 
     switch (iport) {
-
     case 0x6:                   /* reset */
-        return 0;
+        control (0);
+        retval = 0;
+        dsp->speaker = 0;
+        break;
 
     case 0xa:                   /* read data */
         if (dsp->out_data_len) {
             retval = dsp->out_data[--dsp->out_data_len];
+            dsp->last_read_byte = retval;
         } else {
-            log("empty output buffer");
-            goto error;
+            retval = dsp->last_read_byte;
+            dolog ("empty output buffer\n");
+            /* goto error; */
         }
         break;
 
-    case 0xc:                   /* 0 can write */
+    case 0xc:                   /* 0xxxxxxx can write */
         retval = 0;
+        if (dsp->out_data_len == sizeof (dsp->out_data)) retval |= 0x80;
         break;
 
     case 0xd:                   /* timer interrupt clear */
-        log("timer interrupt clear");
+        dolog ("timer interrupt clear\n");
         goto error;
 
     case 0xe:                   /* data available status | irq 8 ack */
         /* XXX drop pic irq line here? */
-        ldebug ("8 ack\n");
-        retval = (0 == dsp->out_data_len) ? 0 : 0x80;
+        /* ldebug ("8 ack\n"); */
+        retval = dsp->out_data_len ? 0x80 : 0;
         dsp->mixer_regs[0x82] &= ~dsp->mixer_regs[0x80];
         pic_set_irq (sb.irq, 0);
         break;
@@ -544,15 +628,30 @@ static IO_READ_PROTO (dsp_read)
         goto error;
     }
 
-    if ((0xc != iport) && (0xe != iport)) {
-        ldebug ("nport=%#x iport %#x = %#x\n",
+    if (0xe == iport) {
+        if (0 == retval) {
+            if (!dsp->nzero) {
+                ldebug ("dsp_read (nport=%#x iport %#x) = %#x, %lld\n",
+                        nport, iport, retval, dsp->nzero);
+            }
+            dsp->nzero += 1;
+        }
+        else {
+            ldebug ("dsp_read (nport=%#x iport %#x) = %#x, %lld\n",
+                    nport, iport, retval, dsp->nzero);
+            dsp->nzero = 0;
+        }
+    }
+    else {
+        ldebug ("dsp_read (nport=%#x iport %#x) = %#x\n",
                 nport, iport, retval);
     }
 
     return retval;
 
  error:
-    return 0;
+    printf ("dsp_read error %#x\n", nport);
+    return 0xff;
 }
 
 static IO_WRITE_PROTO(mixer_write_indexb)
@@ -564,12 +663,100 @@ static IO_WRITE_PROTO(mixer_write_indexb)
 static IO_WRITE_PROTO(mixer_write_datab)
 {
     SB16State *dsp = opaque;
+    int i;
 
-    if (dsp->mixer_nreg > 0x83)
+    linfo ("mixer [%#x] <- %#x\n", dsp->mixer_nreg, val);
+    switch (dsp->mixer_nreg) {
+    case 0x00:
+        /* Bochs */
+        dsp->mixer_regs[0x04] = 0xcc;
+        dsp->mixer_regs[0x0a] = 0x00;
+        dsp->mixer_regs[0x22] = 0xcc;
+        dsp->mixer_regs[0x26] = 0xcc;
+        dsp->mixer_regs[0x28] = 0x00;
+        dsp->mixer_regs[0x2e] = 0x00;
+        dsp->mixer_regs[0x3c] = 0x1f;
+        dsp->mixer_regs[0x3d] = 0x15;
+        dsp->mixer_regs[0x3e] = 0x0b;
+
+        for (i = 0x30; i <= 0x35; i++)
+            dsp->mixer_regs[i] = 0xc0;
+
+        for (i = 0x36; i <= 0x3b; i++)
+            dsp->mixer_regs[i] = 0x00;
+
+        for (i = 0x3f; i <= 0x43; i++)
+            dsp->mixer_regs[i] = 0x00;
+
+        for (i = 0x44; i <= 0x47; i++)
+            dsp->mixer_regs[i] = 0x80;
+
+        for (i = 0x30; i < 0x48; i++) {
+            dsp->mixer_regs[i] = 0x20;
+        }
+        break;
+
+    case 0x04:
+    case 0x0a:
+    case 0x22:
+    case 0x26:
+    case 0x28:
+    case 0x2e:
+    case 0x30:
+    case 0x31:
+    case 0x32:
+    case 0x33:
+    case 0x34:
+    case 0x35:
+    case 0x36:
+    case 0x37:
+    case 0x38:
+    case 0x39:
+    case 0x3a:
+    case 0x3b:
+    case 0x3c:
+    case 0x3d:
+    case 0x3e:
+    case 0x3f:
+    case 0x40:
+    case 0x41:
+    case 0x42:
+    case 0x43:
+    case 0x44:
+    case 0x45:
+    case 0x46:
+    case 0x47:
+    case 0x80:
+    case 0x81:
+        break;
+    default:
         return;
+    }
     dsp->mixer_regs[dsp->mixer_nreg] = val;
 }
 
+static IO_WRITE_PROTO(mpu_write)
+{
+    linfo ("mpu: %#x\n", val);
+}
+
+static IO_WRITE_PROTO(adlib_write)
+{
+    linfo ("adlib: %#x\n", val);
+}
+
+static IO_READ_PROTO(mpu_read)
+{
+    linfo ("mpu read: %#x\n", nport);
+    return 0x80;
+}
+
+static IO_READ_PROTO(adlib_read)
+{
+    linfo ("adlib read: %#x\n", nport);
+    return 0;
+}
+
 static IO_WRITE_PROTO(mixer_write_indexw)
 {
     mixer_write_indexb (opaque, nport, val & 0xff);
@@ -579,6 +766,7 @@ static IO_WRITE_PROTO(mixer_write_indexw)
 static IO_READ_PROTO(mixer_read)
 {
     SB16State *dsp = opaque;
+    linfo ("mixer [%#x] -> %#x\n", dsp->mixer_nreg, dsp->mixer_regs[dsp->mixer_nreg]);
     return dsp->mixer_regs[dsp->mixer_nreg];
 }
 
@@ -637,6 +825,8 @@ static int SB_read_DMA (void *opaque, target_ulong addr, int size)
         return 0;
 
     if (dsp->left_till_irq < 0) {
+	ldebug ("left_till_irq < 0, %d, pos %d \n",
+                dsp->left_till_irq, dsp->dma_buffer_size);
         dsp->left_till_irq += dsp->dma_buffer_size;
         return dsp->dma_pos;
     }
@@ -644,6 +834,7 @@ static int SB_read_DMA (void *opaque, target_ulong addr, int size)
     free = AUD_get_free ();
 
     if ((free <= 0) || (0 == size)) {
+        ldebug ("returning, since free = %d and size = %d\n", free, size);
         return dsp->dma_pos;
     }
 
@@ -656,8 +847,11 @@ static int SB_read_DMA (void *opaque, target_ulong addr, int size)
 
     till = dsp->left_till_irq;
 
+#ifdef DEBUG_SB16_MOST
     ldebug ("addr:%#010x free:%d till:%d size:%d\n",
             addr, free, till, size);
+#endif
+
     if (till <= copy) {
         if (0 == dsp->dma_auto) {
             copy = till;
@@ -671,7 +865,8 @@ static int SB_read_DMA (void *opaque, target_ulong addr, int size)
     if (dsp->left_till_irq <= 0) {
         dsp->mixer_regs[0x82] |= dsp->mixer_regs[0x80];
         if (0 == noirq) {
-            ldebug ("request irq\n");
+            ldebug ("request irq pos %d, left %d\n",
+                    dsp->dma_pos, dsp->left_till_irq);
             pic_set_irq(sb.irq, 1);
         }
 
@@ -680,9 +875,11 @@ static int SB_read_DMA (void *opaque, target_ulong addr, int size)
         }
     }
 
+#ifdef DEBUG_SB16_MOST
     ldebug ("pos %5d free %5d size %5d till % 5d copy %5d dma size %5d\n",
             dsp->dma_pos, free, size, dsp->left_till_irq, copy,
             dsp->dma_buffer_size);
+#endif
 
     if (dsp->left_till_irq <= 0) {
         dsp->left_till_irq += dsp->dma_buffer_size;
@@ -703,7 +900,7 @@ static int magic_of_irq (int irq)
     case 10:
         return 8;
     default:
-        log ("bad irq %d", irq);
+        dolog ("bad irq %d\n", irq);
         return 2;
     }
 }
@@ -721,12 +918,42 @@ static int irq_of_magic (int magic)
     case 8:
         return 10;
     default:
-        log ("bad irq magic %d", magic);
+        dolog ("bad irq magic %d\n", magic);
         return 2;
     }
 }
 #endif
 
+#ifdef SB16_TRAP_ALL
+static IO_READ_PROTO (trap_read)
+{
+    switch (nport) {
+    case 0x220:
+        return 0;
+    case 0x226:
+    case 0x22a:
+    case 0x22c:
+    case 0x22d:
+    case 0x22e:
+    case 0x22f:
+        return dsp_read (opaque, nport);
+    }
+    linfo ("trap_read: %#x\n", nport);
+    return 0xff;
+}
+
+static IO_WRITE_PROTO (trap_write)
+{
+    switch (nport) {
+    case 0x226:
+    case 0x22c:
+        dsp_write (opaque, nport, val);
+        return;
+    }
+    linfo ("trap_write: %#x = %#x\n", nport, val);
+}
+#endif
+
 void SB16_init (void)
 {
     SB16State *s = &dsp;
@@ -736,13 +963,23 @@ void SB16_init (void)
 
     memset(s->mixer_regs, 0xff, sizeof(s->mixer_regs));
 
+    s->mixer_regs[0x00] = 0;
     s->mixer_regs[0x0e] = ~0;
     s->mixer_regs[0x80] = magic_of_irq (sb.irq);
-    s->mixer_regs[0x81] = 0x20 | (sb.dma << 1);
-
-    for (i = 0x30; i < 0x48; i++) {
-        s->mixer_regs[i] = 0x20;
+    s->mixer_regs[0x81] = 0x80 | 0x10 | (sb.dma << 1);
+    s->mixer_regs[0x82] = 0;
+    s->mixer_regs[0xfd] = 16;   /* bochs */
+    s->mixer_regs[0xfe] = 6;    /* bochs */
+    mixer_write_indexw (s, 0x224, 0);
+
+#ifdef SB16_TRAP_ALL
+    for (i = 0; i < 0x100; i++) {
+        if (i != 4 && i != 5) {
+            register_ioport_write (sb.port + i, 1, 1, trap_write, s);
+            register_ioport_read (sb.port + i, 1, 1, trap_read, s);
+        }
     }
+#else
 
     for (i = 0; i < LENOFA (dsp_write_ports); i++) {
         register_ioport_write (sb.port + dsp_write_ports[i], 1, 1, dsp_write, s);
@@ -751,12 +988,20 @@ void SB16_init (void)
     for (i = 0; i < LENOFA (dsp_read_ports); i++) {
         register_ioport_read (sb.port + dsp_read_ports[i], 1, 1, dsp_read, s);
     }
+#endif
 
     register_ioport_write (sb.port + 0x4, 1, 1, mixer_write_indexb, s);
     register_ioport_write (sb.port + 0x4, 1, 2, mixer_write_indexw, s);
     register_ioport_read (sb.port + 0x5, 1, 1, mixer_read, s);
     register_ioport_write (sb.port + 0x5, 1, 1, mixer_write_datab, s);
 
+    for (i = 0; 4 < 4; i++) {
+        register_ioport_read (0x330 + i, 1, 1, mpu_read, s);
+        register_ioport_write (0x330 + i, 1, 1, mpu_write, s);
+        register_ioport_read (0x388 + i, 1, 1, adlib_read, s);
+        register_ioport_write (0x388 + i, 1, 1, adlib_write, s);
+    }
+
     DMA_register_channel (sb.hdma, SB_read_DMA, s);
     DMA_register_channel (sb.dma, SB_read_DMA, s);
 }
diff --git a/oss.c b/oss.c
index 40c9462cf3..91eb47e491 100644
--- a/oss.c
+++ b/oss.c
@@ -23,22 +23,446 @@
  */
 #include "vl.h"
 
-#if !defined(_WIN32) && !defined(__APPLE__)
-#include <ctype.h>
+#include <stdio.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* TODO: Graceful error handling */
+
+#if defined(_WIN32)
+#define USE_SDL_AUDIO
+#endif
+
+#define MIN(a, b) ((a)>(b)?(b):(a))
+#define MAX(a, b) ((a)<(b)?(b):(a))
+
+#define DEREF(x) (void)x
+#define dolog(...) fprintf (stderr, "audio: " __VA_ARGS__)
+#define ERRFail(...) do {                                               \
+    int _errno = errno;                                                 \
+    fprintf (stderr, "audio: " __VA_ARGS__);                            \
+    fprintf (stderr, "\nsystem error: %s\n", strerror (_errno));        \
+    abort ();                                                           \
+} while (0)
+#define Fail(...) do {                          \
+    fprintf (stderr, "audio: " __VA_ARGS__);    \
+    fprintf (stderr, "\n");                     \
+    abort ();                                   \
+} while (0)
+
+#ifdef DEBUG_AUDIO
+#define lwarn(...) fprintf (stderr, "audio: " __VA_ARGS__)
+#define linfo(...) fprintf (stderr, "audio: " __VA_ARGS__)
+#define ldebug(...) fprintf (stderr, "audio: " __VA_ARGS__)
+#else
+#define lwarn(...)
+#define linfo(...)
+#define ldebug(...)
+#endif
+
+static int get_conf_val (const char *key, int defval)
+{
+    int val = defval;
+    char *strval;
+
+    strval = getenv (key);
+    if (strval) {
+        val = atoi (strval);
+    }
+
+    return val;
+}
+
+static void copy_no_conversion (void *dst, void *src, int size)
+{
+    memcpy (dst, src, size);
+}
+
+static void copy_u16_to_s16 (void *dst, void *src, int size)
+{
+    int i;
+    uint16_t *out, *in;
+
+    out = dst;
+    in = src;
+
+    for (i = 0; i < size / 2; i++) {
+        out[i] = in[i] + 0x8000;
+    }
+}
+
+#ifdef USE_SDL_AUDIO
+#include <SDL/SDL.h>
+#include <SDL/SDL_thread.h>
+
+static struct {
+    int samples;
+} conf = {
+    .samples = 4096
+};
+
+typedef struct AudioState {
+    int freq;
+    int bits16;
+    int nchannels;
+    int rpos;
+    int wpos;
+    volatile int live;
+    volatile int exit;
+    int bytes_per_second;
+    Uint8 *buf;
+    int bufsize;
+    int leftover;
+    uint64_t old_ticks;
+    SDL_AudioSpec spec;
+    SDL_mutex *mutex;
+    SDL_sem *sem;
+    void (*copy_fn)(void *, void *, int);
+} AudioState;
+
+static AudioState sdl_audio;
+
+void AUD_run (void)
+{
+}
+
+static void own (AudioState *s)
+{
+    /* SDL_LockAudio (); */
+    if (SDL_mutexP (s->mutex))
+        dolog ("SDL_mutexP: %s\n", SDL_GetError ());
+}
+
+static void disown (AudioState *s)
+{
+    /* SDL_UnlockAudio (); */
+    if (SDL_mutexV (s->mutex))
+        dolog ("SDL_mutexV: %s\n", SDL_GetError ());
+}
+
+static void sem_wait (AudioState *s)
+{
+    if (SDL_SemWait (s->sem))
+        dolog ("SDL_SemWait: %s\n", SDL_GetError ());
+}
+
+static void sem_post (AudioState *s)
+{
+    if (SDL_SemPost (s->sem))
+        dolog ("SDL_SemPost: %s\n", SDL_GetError ());
+}
+
+static void audio_callback (void *data, Uint8 *stream, int len)
+{
+    int to_mix;
+    AudioState *s = data;
+
+    if (s->exit) return;
+    while (len) {
+        sem_wait (s);
+        if (s->exit) return;
+        own (s);
+        to_mix = MIN (len, s->live);
+        len -= to_mix;
+        /* printf ("to_mix=%d len=%d live=%d\n", to_mix, len, s->live); */
+        while (to_mix) {
+            int chunk = MIN (to_mix, s->bufsize - s->rpos);
+            /* SDL_MixAudio (stream, buf, chunk, SDL_MIX_MAXVOLUME); */
+            memcpy (stream, s->buf + s->rpos, chunk);
+
+            s->rpos += chunk;
+            s->live -= chunk;
+
+            stream += chunk;
+            to_mix -= chunk;
+
+            if (s->rpos == s->bufsize) s->rpos = 0;
+        }
+        disown (s);
+    }
+}
+
+static void sem_zero (AudioState *s)
+{
+    int res;
+
+    do {
+        res = SDL_SemTryWait (s->sem);
+        if (res < 0) {
+            dolog ("SDL_SemTryWait: %s\n", SDL_GetError ());
+            return;
+        }
+    } while (res != SDL_MUTEX_TIMEDOUT);
+}
+
+static void do_open (AudioState *s)
+{
+    int status;
+    SDL_AudioSpec obtained;
+
+    SDL_PauseAudio (1);
+    if (s->buf) {
+        s->exit = 1;
+        sem_post (s);
+        SDL_CloseAudio ();
+        s->exit = 0;
+        qemu_free (s->buf);
+        s->buf = NULL;
+        sem_zero (s);
+    }
+
+    s->bytes_per_second = (s->spec.freq << (s->spec.channels >> 1)) << s->bits16;
+    s->spec.samples = conf.samples;
+    s->spec.userdata = s;
+    s->spec.callback = audio_callback;
+
+    status = SDL_OpenAudio (&s->spec, &obtained);
+    if (status < 0) {
+        dolog ("SDL_OpenAudio: %s\n", SDL_GetError ());
+        goto exit;
+    }
+
+    if (obtained.freq != s->spec.freq ||
+        obtained.channels != s->spec.channels ||
+        obtained.format != s->spec.format) {
+        dolog ("Audio spec mismatch requested obtained\n"
+               "freq                %5d    %5d\n"
+               "channels            %5d    %5d\n"
+               "fmt                 %5d    %5d\n",
+               s->spec.freq, obtained.freq,
+               s->spec.channels, obtained.channels,
+               s->spec.format, obtained.format
+            );
+    }
+
+    s->bufsize = obtained.size;
+    s->buf = qemu_mallocz (s->bufsize);
+    if (!s->buf) {
+        dolog ("qemu_mallocz(%d)\n", s->bufsize);
+        goto exit;
+    }
+    SDL_PauseAudio (0);
+
+exit:
+    s->rpos = 0;
+    s->wpos = 0;
+    s->live = 0;
+}
+
+int AUD_write (void *in_buf, int size)
+{
+    AudioState *s = &sdl_audio;
+    int to_copy, temp;
+    uint8_t *in, *out;
+
+    own (s);
+    to_copy = MIN (s->bufsize - s->live, size);
+
+    temp = to_copy;
+
+    in = in_buf;
+    out = s->buf;
+
+    while (temp) {
+        int copy;
+
+        copy = MIN (temp, s->bufsize - s->wpos);
+        s->copy_fn (out + s->wpos, in, copy);
+
+        s->wpos += copy;
+        if (s->wpos == s->bufsize) {
+            s->wpos = 0;
+        }
+
+        temp -= copy;
+        in += copy;
+        s->live += copy;
+    }
+
+    disown (s);
+    sem_post (s);
+    return to_copy;
+}
+
+static void maybe_open (AudioState *s, int req_freq, int req_nchannels,
+                        audfmt_e req_fmt, int force_open)
+{
+    int sdl_fmt, bits16;
+
+    switch (req_fmt) {
+    case AUD_FMT_U8:
+        bits16 = 0;
+        sdl_fmt = AUDIO_U8;
+        s->copy_fn = copy_no_conversion;
+        break;
+
+    case AUD_FMT_S8:
+        fprintf (stderr, "audio: can not play 8bit signed\n");
+        return;
+
+    case AUD_FMT_S16:
+        bits16 = 1;
+        sdl_fmt = AUDIO_S16;
+        s->copy_fn = copy_no_conversion;
+        break;
+
+    case AUD_FMT_U16:
+        bits16 = 1;
+        sdl_fmt = AUDIO_S16;
+        s->copy_fn = copy_u16_to_s16;
+        break;
+
+    default:
+        abort ();
+    }
+
+    if (force_open
+        || (NULL == s->buf)
+        || (sdl_fmt != s->spec.format)
+        || (req_nchannels != s->spec.channels)
+        || (req_freq != s->spec.freq)
+        || (bits16 != s->bits16)) {
+
+        s->spec.format = sdl_fmt;
+        s->spec.channels = req_nchannels;
+        s->spec.freq = req_freq;
+        s->bits16 = bits16;
+        do_open (s);
+    }
+}
+
+void AUD_reset (int req_freq, int req_nchannels, audfmt_e req_fmt)
+{
+    AudioState *s = &sdl_audio;
+    own (s);
+    maybe_open (s, req_freq, req_nchannels, req_fmt, 0);
+    disown (s);
+}
+
+void AUD_open (int req_freq, int req_nchannels, audfmt_e req_fmt)
+{
+    AudioState *s = &sdl_audio;
+    own (s);
+    maybe_open (s, req_freq, req_nchannels, req_fmt, 1);
+    disown (s);
+}
+
+void AUD_adjust_estimate (int leftover)
+{
+    AudioState *s = &sdl_audio;
+    own (s);
+    s->leftover = leftover;
+    disown (s);
+}
+
+int AUD_get_free (void)
+{
+    int free, elapsed;
+    uint64_t ticks, delta;
+    uint64_t ua_elapsed;
+    uint64_t al_elapsed;
+    AudioState *s = &sdl_audio;
+
+    own (s);
+    free = s->bufsize - s->live;
+
+    if (0 == free) {
+        disown (s);
+        return 0;
+    }
+
+    elapsed = free;
+    ticks = qemu_get_clock(rt_clock);
+    delta = ticks - s->old_ticks;
+    s->old_ticks = ticks;
+
+    ua_elapsed = (delta * s->bytes_per_second) / 1000;
+    al_elapsed = ua_elapsed & ~3ULL;
+
+    ldebug ("tid elapsed %llu bytes\n", ua_elapsed);
+
+    if (al_elapsed > (uint64_t) INT_MAX)
+        elapsed = INT_MAX;
+    else
+        elapsed = al_elapsed;
+
+    elapsed += s->leftover;
+    disown (s);
+
+    if (elapsed > free) {
+        lwarn ("audio can not keep up elapsed %d free %d\n", elapsed, free);
+        return free;
+    }
+    else {
+        return elapsed;
+    }
+}
+
+int AUD_get_live (void)
+{
+    int live;
+    AudioState *s = &sdl_audio;
+
+    own (s);
+    live = s->live;
+    disown (s);
+    return live;
+}
+
+int AUD_get_buffer_size (void)
+{
+    int bufsize;
+    AudioState *s = &sdl_audio;
+
+    own (s);
+    bufsize = s->bufsize;
+    disown (s);
+    return bufsize;
+}
+
+#define QC_SDL_NSAMPLES "QEMU_SDL_NSAMPLES"
+
+static void cleanup (void)
+{
+    AudioState *s = &sdl_audio;
+    own (s);
+    s->exit = 1;
+    sem_post (s);
+    disown (s);
+}
+
+void AUD_init (void)
+{
+    AudioState *s = &sdl_audio;
+
+    atexit (cleanup);
+    SDL_InitSubSystem (SDL_INIT_AUDIO);
+    s->mutex = SDL_CreateMutex ();
+    if (!s->mutex) {
+        dolog ("SDL_CreateMutex: %s\n", SDL_GetError ());
+        return;
+    }
+
+    s->sem = SDL_CreateSemaphore (0);
+    if (!s->sem) {
+        dolog ("SDL_CreateSemaphore: %s\n", SDL_GetError ());
+        return;
+    }
+
+    conf.samples = get_conf_val (QC_SDL_NSAMPLES, conf.samples);
+}
+
+#elif !defined(_WIN32) && !defined(__APPLE__)
+
 #include <fcntl.h>
 #include <errno.h>
-#include <stdio.h>
 #include <unistd.h>
-#include <string.h>
-#include <stdlib.h>
-#include <limits.h>
-#include <inttypes.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/ioctl.h>
 #include <sys/soundcard.h>
 
-
 /* http://www.df.lth.se/~john_e/gems/gem002d.html */
 /* http://www.multi-platforms.com/Tips/PopCount.htm */
 static inline uint32_t popcount (uint32_t u)
@@ -56,34 +480,6 @@ static inline uint32_t lsbindex (uint32_t u)
   return popcount ((u&-u)-1);
 }
 
-#define MIN(a, b) ((a)>(b)?(b):(a))
-#define MAX(a, b) ((a)<(b)?(b):(a))
-
-#define DEREF(x) (void)x
-#define log(...) fprintf (stderr, "oss: " __VA_ARGS__)
-#define ERRFail(...) do {                                       \
-    int _errno = errno;                                         \
-    fprintf (stderr, "oss: " __VA_ARGS__);                      \
-    fprintf (stderr, "system error: %s\n", strerror (_errno));  \
-    abort ();                                                   \
-} while (0)
-#define Fail(...) do {                          \
-    fprintf (stderr, "oss: " __VA_ARGS__);      \
-    fprintf (stderr, "\n");                     \
-    abort ();                                   \
-} while (0)
-
-#ifdef DEBUG_OSS
-#define lwarn(...) fprintf (stderr, "oss: " __VA_ARGS__)
-#define linfo(...) fprintf (stderr, "oss: " __VA_ARGS__)
-#define ldebug(...) fprintf (stderr, "oss: " __VA_ARGS__)
-#else
-#define lwarn(...)
-#define linfo(...)
-#define ldebug(...)
-#endif
-
-
 #define IOCTL(args) do {                        \
   int ret = ioctl args;                         \
   if (-1 == ret) {                              \
@@ -92,7 +488,7 @@ static inline uint32_t lsbindex (uint32_t u)
   ldebug ("ioctl " #args " = %d\n", ret);       \
 } while (0)
 
-static struct {
+typedef struct AudioState {
     int fd;
     int freq;
     int bits16;
@@ -111,7 +507,9 @@ static struct {
     int leftover;
     uint64_t old_ticks;
     void (*copy_fn)(void *, void *, int);
-} oss = { .fd = -1 };
+} AudioState;
+
+static AudioState oss_audio = { .fd = -1 };
 
 static struct {
     int try_mmap;
@@ -125,25 +523,7 @@ static struct {
 
 static enum {DONT, DSP, TID} est = DONT;
 
-static void copy_no_conversion (void *dst, void *src, int size)
-{
-    memcpy (dst, src, size);
-}
-
-static void copy_u16_to_s16 (void *dst, void *src, int size)
-{
-    int i;
-    uint16_t *out, *in;
-
-    out = dst;
-    in = src;
-
-    for (i = 0; i < size / 2; i++) {
-        out[i] = in[i] + 0x8000;
-    }
-}
-
-static void pab (struct audio_buf_info *abinfo)
+static void pab (AudioState *s, struct audio_buf_info *abinfo)
 {
     DEREF (abinfo);
 
@@ -153,118 +533,122 @@ static void pab (struct audio_buf_info *abinfo)
             abinfo->fragstotal,
             abinfo->fragsize,
             abinfo->bytes,
-            rpos, wpos, live);
+            s->rpos, s->wpos, s->live);
 }
 
-static void do_open ()
+static void do_open (AudioState *s)
 {
     int mmmmssss;
     audio_buf_info abinfo;
     int fmt, freq, nchannels;
 
-    if (oss.buf) {
-        if (-1 == munmap (oss.buf, oss.bufsize)) {
+    if (s->buf) {
+        if (s->is_mapped) {
+            if (-1 == munmap (s->buf, s->bufsize)) {
             ERRFail ("failed to unmap audio buffer %p %d",
-                     oss.buf, oss.bufsize);
+                         s->buf, s->bufsize);
+        }
         }
-        oss.buf = NULL;
+        else {
+            qemu_free (s->buf);
+        }
+        s->buf = NULL;
     }
 
-    if (-1 != oss.fd)
-        close (oss.fd);
+    if (-1 != s->fd)
+        close (s->fd);
 
-    oss.fd = open ("/dev/dsp", O_RDWR | O_NONBLOCK);
-    if (-1 == oss.fd) {
+    s->fd = open ("/dev/dsp", O_RDWR | O_NONBLOCK);
+    if (-1 == s->fd) {
         ERRFail ("can not open /dev/dsp");
     }
 
-    fmt = oss.oss_fmt;
-    freq = oss.freq;
-    nchannels = oss.nchannels;
+    fmt = s->oss_fmt;
+    freq = s->freq;
+    nchannels = s->nchannels;
 
-    IOCTL ((oss.fd, SNDCTL_DSP_RESET, 1));
-    IOCTL ((oss.fd, SNDCTL_DSP_SAMPLESIZE, &fmt));
-    IOCTL ((oss.fd, SNDCTL_DSP_CHANNELS, &nchannels));
-    IOCTL ((oss.fd, SNDCTL_DSP_SPEED, &freq));
-    IOCTL ((oss.fd, SNDCTL_DSP_NONBLOCK));
+    IOCTL ((s->fd, SNDCTL_DSP_RESET, 1));
+    IOCTL ((s->fd, SNDCTL_DSP_SAMPLESIZE, &fmt));
+    IOCTL ((s->fd, SNDCTL_DSP_CHANNELS, &nchannels));
+    IOCTL ((s->fd, SNDCTL_DSP_SPEED, &freq));
+    IOCTL ((s->fd, SNDCTL_DSP_NONBLOCK));
 
     mmmmssss = (conf.nfrags << 16) | conf.fragsize;
-    IOCTL ((oss.fd, SNDCTL_DSP_SETFRAGMENT, &mmmmssss));
+    IOCTL ((s->fd, SNDCTL_DSP_SETFRAGMENT, &mmmmssss));
 
-    if ((oss.oss_fmt != fmt)
-        || (oss.nchannels != nchannels)
-        || (oss.freq != freq)) {
+    if ((s->oss_fmt != fmt)
+        || (s->nchannels != nchannels)
+        || (s->freq != freq)) {
         Fail ("failed to set audio parameters\n"
               "parameter | requested value | obtained value\n"
               "format    |      %10d |     %10d\n"
               "channels  |      %10d |     %10d\n"
               "frequency |      %10d |     %10d\n",
-              oss.oss_fmt, fmt,
-              oss.nchannels, nchannels,
-              oss.freq, freq);
+              s->oss_fmt, fmt,
+              s->nchannels, nchannels,
+              s->freq, freq);
     }
 
-    IOCTL ((oss.fd, SNDCTL_DSP_GETOSPACE, &abinfo));
+    IOCTL ((s->fd, SNDCTL_DSP_GETOSPACE, &abinfo));
 
-    oss.nfrags = abinfo.fragstotal;
-    oss.fragsize = abinfo.fragsize;
-    oss.bufsize = oss.nfrags * oss.fragsize;
-    oss.old_optr = 0;
+    s->nfrags = abinfo.fragstotal;
+    s->fragsize = abinfo.fragsize;
+    s->bufsize = s->nfrags * s->fragsize;
+    s->old_optr = 0;
 
-    oss.bytes_per_second = (freq << (nchannels >> 1)) << oss.bits16;
+    s->bytes_per_second = (freq << (nchannels >> 1)) << s->bits16;
 
-    linfo ("bytes per second %d\n", oss.bytes_per_second);
+    linfo ("bytes per second %d\n", s->bytes_per_second);
 
     linfo ("fragments %d, fragstotal %d, fragsize %d, bytes %d, bufsize %d\n",
            abinfo.fragments,
            abinfo.fragstotal,
            abinfo.fragsize,
            abinfo.bytes,
-           oss.bufsize);
+           s->bufsize);
 
-    oss.buf = MAP_FAILED;
-    oss.is_mapped = 0;
+    s->buf = MAP_FAILED;
+    s->is_mapped = 0;
 
     if (conf.try_mmap) {
-        oss.buf = mmap (NULL, oss.bufsize, PROT_WRITE, MAP_SHARED, oss.fd, 0);
-        if (MAP_FAILED == oss.buf) {
+        s->buf = mmap (NULL, s->bufsize, PROT_WRITE, MAP_SHARED, s->fd, 0);
+        if (MAP_FAILED == s->buf) {
             int err;
 
             err = errno;
-            log ("failed to mmap audio, size %d, fd %d\n"
+            dolog ("failed to mmap audio, size %d, fd %d\n"
                  "syserr: %s\n",
-                 oss.bufsize, oss.fd, strerror (err));
+                   s->bufsize, s->fd, strerror (err));
         }
     else {
             est = TID;
-            oss.is_mapped = 1;
+            s->is_mapped = 1;
         }
     }
 
-    if (MAP_FAILED == oss.buf) {
+    if (MAP_FAILED == s->buf) {
         est = TID;
-        oss.buf = mmap (NULL, oss.bufsize, PROT_READ | PROT_WRITE,
-                        MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
-        if (MAP_FAILED == oss.buf) {
-            ERRFail ("mmap audio buf, size %d", oss.bufsize);
+        s->buf = qemu_mallocz (s->bufsize);
+        if (!s->buf) {
+            ERRFail ("audio buf malloc failed, size %d", s->bufsize);
         }
     }
 
-    oss.rpos = 0;
-    oss.wpos = 0;
-    oss.live = 0;
+    s->rpos = 0;
+    s->wpos = 0;
+    s->live = 0;
 
-    if (oss.is_mapped) {
+    if (s->is_mapped) {
         int trig;
 
         trig = 0;
-        IOCTL ((oss.fd, SNDCTL_DSP_SETTRIGGER, &trig));
+        IOCTL ((s->fd, SNDCTL_DSP_SETTRIGGER, &trig));
         trig = PCM_ENABLE_OUTPUT;
-        IOCTL ((oss.fd, SNDCTL_DSP_SETTRIGGER, &trig));
+        IOCTL ((s->fd, SNDCTL_DSP_SETTRIGGER, &trig));
     }
 }
 
-static void maybe_open (int req_freq, int req_nchannels,
+static void maybe_open (AudioState *s, int req_freq, int req_nchannels,
                         audfmt_e req_fmt, int force_open)
 {
     int oss_fmt, bits16;
@@ -273,7 +657,7 @@ static void maybe_open (int req_freq, int req_nchannels,
     case AUD_FMT_U8:
         bits16 = 0;
         oss_fmt = AFMT_U8;
-        oss.copy_fn = copy_no_conversion;
+        s->copy_fn = copy_no_conversion;
         break;
 
     case AUD_FMT_S8:
@@ -282,13 +666,13 @@ static void maybe_open (int req_freq, int req_nchannels,
     case AUD_FMT_S16:
         bits16 = 1;
         oss_fmt = AFMT_S16_LE;
-        oss.copy_fn = copy_no_conversion;
+        s->copy_fn = copy_no_conversion;
         break;
 
     case AUD_FMT_U16:
         bits16 = 1;
         oss_fmt = AFMT_S16_LE;
-        oss.copy_fn = copy_u16_to_s16;
+        s->copy_fn = copy_u16_to_s16;
         break;
 
     default:
@@ -296,55 +680,58 @@ static void maybe_open (int req_freq, int req_nchannels,
     }
 
     if (force_open
-        || (-1 == oss.fd)
-        || (oss_fmt != oss.oss_fmt)
-        || (req_nchannels != oss.nchannels)
-        || (req_freq != oss.freq)
-        || (bits16 != oss.bits16)) {
-        oss.oss_fmt = oss_fmt;
-        oss.nchannels = req_nchannels;
-        oss.freq = req_freq;
-        oss.bits16 = bits16;
-        do_open ();
+        || (-1 == s->fd)
+        || (oss_fmt != s->oss_fmt)
+        || (req_nchannels != s->nchannels)
+        || (req_freq != s->freq)
+        || (bits16 != s->bits16)) {
+        s->oss_fmt = oss_fmt;
+        s->nchannels = req_nchannels;
+        s->freq = req_freq;
+        s->bits16 = bits16;
+        do_open (s);
     }
 }
 
 void AUD_reset (int req_freq, int req_nchannels, audfmt_e req_fmt)
 {
-    maybe_open (req_freq, req_nchannels, req_fmt, 0);
+    AudioState *s = &oss_audio;
+    maybe_open (s, req_freq, req_nchannels, req_fmt, 0);
 }
 
 void AUD_open (int req_freq, int req_nchannels, audfmt_e req_fmt)
 {
-    maybe_open (req_freq, req_nchannels, req_fmt, 1);
+    AudioState *s = &oss_audio;
+    maybe_open (s, req_freq, req_nchannels, req_fmt, 1);
 }
 
 int AUD_write (void *in_buf, int size)
 {
+    AudioState *s = &oss_audio;
     int to_copy, temp;
     uint8_t *in, *out;
 
-    to_copy = MIN (oss.bufsize - oss.live, size);
+    to_copy = MIN (s->bufsize - s->live, size);
 
     temp = to_copy;
 
     in = in_buf;
-    out = oss.buf;
+    out = s->buf;
 
     while (temp) {
         int copy;
 
-        copy = MIN (temp, oss.bufsize - oss.wpos);
-        oss.copy_fn (out + oss.wpos, in, copy);
+        copy = MIN (temp, s->bufsize - s->wpos);
+        s->copy_fn (out + s->wpos, in, copy);
 
-        oss.wpos += copy;
-        if (oss.wpos == oss.bufsize) {
-            oss.wpos = 0;
+        s->wpos += copy;
+        if (s->wpos == s->bufsize) {
+            s->wpos = 0;
         }
 
         temp -= copy;
         in += copy;
-        oss.live += copy;
+        s->live += copy;
     }
 
     return to_copy;
@@ -355,15 +742,16 @@ void AUD_run (void)
     int res;
     int bytes;
     struct audio_buf_info abinfo;
+    AudioState *s = &oss_audio;
 
-    if (0 == oss.live)
+    if (0 == s->live)
         return;
 
-    if (oss.is_mapped) {
+    if (s->is_mapped) {
         count_info info;
 
-        res = ioctl (oss.fd, SNDCTL_DSP_GETOPTR, &info);
-        if (-1 == res) {
+        res = ioctl (s->fd, SNDCTL_DSP_GETOPTR, &info);
+        if (res < 0) {
             int err;
 
             err = errno;
@@ -371,29 +759,30 @@ void AUD_run (void)
             return;
         }
 
-        if (info.ptr > oss.old_optr) {
-            bytes = info.ptr - oss.old_optr;
+        if (info.ptr > s->old_optr) {
+            bytes = info.ptr - s->old_optr;
         }
         else {
-            bytes = oss.bufsize + info.ptr - oss.old_optr;
+            bytes = s->bufsize + info.ptr - s->old_optr;
         }
 
-        oss.old_optr = info.ptr;
-        oss.live -= bytes;
+        s->old_optr = info.ptr;
+        s->live -= bytes;
         return;
     }
 
-    res = ioctl (oss.fd, SNDCTL_DSP_GETOSPACE, &abinfo);
+    res = ioctl (s->fd, SNDCTL_DSP_GETOSPACE, &abinfo);
 
-    if (-1 == res) {
+    if (res < 0) {
         int err;
 
         err = errno;
         lwarn ("SNDCTL_DSP_GETOSPACE failed with %s\n", strerror (err));
+        return;
     }
 
     bytes = abinfo.bytes;
-    bytes = MIN (oss.live, bytes);
+    bytes = MIN (s->live, bytes);
 #if 0
     bytes = (bytes / fragsize) * fragsize;
 #endif
@@ -401,9 +790,9 @@ void AUD_run (void)
     while (bytes) {
         int left, play, written;
 
-        left = oss.bufsize - oss.rpos;
+        left = s->bufsize - s->rpos;
         play = MIN (left, bytes);
-        written = write (oss.fd, (uint8_t *)oss.buf + oss.rpos, play);
+        written = write (s->fd, (uint8_t *)s->buf + s->rpos, play);
 
         if (-1 == written) {
             if (EAGAIN == errno || EINTR == errno) {
@@ -415,12 +804,12 @@ void AUD_run (void)
         }
 
         play = written;
-        oss.live -= play;
-        oss.rpos += play;
+        s->live -= play;
+        s->rpos += play;
         bytes -= play;
 
-        if (oss.rpos == oss.bufsize) {
-            oss.rpos = 0;
+        if (s->rpos == s->bufsize) {
+            s->rpos = 0;
         }
     }
 }
@@ -429,8 +818,9 @@ static int get_dsp_bytes (void)
 {
     int res;
     struct count_info info;
+    AudioState *s = &oss_audio;
 
-    res = ioctl (oss.fd, SNDCTL_DSP_GETOPTR, &info);
+    res = ioctl (s->fd, SNDCTL_DSP_GETOPTR, &info);
     if (-1 == res) {
         int err;
 
@@ -446,16 +836,18 @@ static int get_dsp_bytes (void)
 
 void AUD_adjust_estimate (int leftover)
 {
-    oss.leftover = leftover;
+    AudioState *s = &oss_audio;
+    s->leftover = leftover;
 }
 
 int AUD_get_free (void)
 {
     int free, elapsed;
+    AudioState *s = &oss_audio;
 
-    free = oss.bufsize - oss.live;
+    free = s->bufsize - s->live;
 
-    if (0 == free)
+    if (free <= 0)
         return 0;
 
     elapsed = free;
@@ -485,10 +877,10 @@ int AUD_get_free (void)
             uint64_t al_elapsed;
 
             ticks = qemu_get_clock(rt_clock);
-            delta = ticks - oss.old_ticks;
-            oss.old_ticks = ticks;
+            delta = ticks - s->old_ticks;
+            s->old_ticks = ticks;
 
-            ua_elapsed = (delta * oss.bytes_per_second) / 1000;
+            ua_elapsed = (delta * s->bytes_per_second) / 1000;
             al_elapsed = ua_elapsed & ~3ULL;
 
             ldebug ("tid elapsed %llu bytes\n", ua_elapsed);
@@ -498,7 +890,7 @@ int AUD_get_free (void)
             else
                 elapsed = al_elapsed;
 
-            elapsed += oss.leftover;
+            elapsed += s->leftover;
         }
     }
 
@@ -513,31 +905,20 @@ int AUD_get_free (void)
 
 int AUD_get_live (void)
 {
-    return oss.live;
+    AudioState *s = &oss_audio;
+    return s->live;
 }
 
 int AUD_get_buffer_size (void)
 {
-    return oss.bufsize;
+    AudioState *s = &oss_audio;
+    return s->bufsize;
 }
 
 #define QC_OSS_FRAGSIZE "QEMU_OSS_FRAGSIZE"
 #define QC_OSS_NFRAGS "QEMU_OSS_NFRAGS"
 #define QC_OSS_MMAP "QEMU_OSS_MMAP"
 
-static int get_conf_val (const char *key, int defval)
-{
-    int val = defval;
-    char *strval;
-
-    strval = getenv (key);
-    if (strval) {
-        val = atoi (strval);
-    }
-
-    return val;
-}
-
 void AUD_init (void)
 {
     int fsp;