audio: replace shift in audio_pcm_info with bytes_per_frame

The bit shifting trick worked because the number of bytes per frame was
always a power-of-two (since QEMU only supports mono, stereo and 8, 16
and 32 bit samples).  But if we want to add support for surround sound,
this no longer holds true.

Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Message-id: 1351fd9bcce0ff20d81850c5292722194329de02.1570996490.git.DirtY.iCE.hu@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

1 files changed, 37 insertions, 37 deletions

diff --git a/audio/audio.c b/audio/audio.c
index f1c145d..c00f4de 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -299,12 +299,13 @@ static int audio_pcm_info_eq (struct audio_pcm_info *info, struct audsettings *a
 
 void audio_pcm_init_info (struct audio_pcm_info *info, struct audsettings *as)
 {
-    int bits = 8, sign = 0, shift = 0;
+    int bits = 8, sign = 0, mul;
 
     switch (as->fmt) {
     case AUDIO_FORMAT_S8:
         sign = 1;
     case AUDIO_FORMAT_U8:
+        mul = 1;
         break;
 
     case AUDIO_FORMAT_S16:
@@ -312,7 +313,7 @@ void audio_pcm_init_info (struct audio_pcm_info *info, struct audsettings *as)
         /* fall through */
     case AUDIO_FORMAT_U16:
         bits = 16;
-        shift = 1;
+        mul = 2;
         break;
 
     case AUDIO_FORMAT_S32:
@@ -320,7 +321,7 @@ void audio_pcm_init_info (struct audio_pcm_info *info, struct audsettings *as)
         /* fall through */
     case AUDIO_FORMAT_U32:
         bits = 32;
-        shift = 2;
+        mul = 4;
         break;
 
     default:
@@ -331,9 +332,8 @@ void audio_pcm_init_info (struct audio_pcm_info *info, struct audsettings *as)
     info->bits = bits;
     info->sign = sign;
     info->nchannels = as->nchannels;
-    info->shift = (as->nchannels == 2) + shift;
-    info->align = (1 << info->shift) - 1;
-    info->bytes_per_second = info->freq << info->shift;
+    info->bytes_per_frame = as->nchannels * mul;
+    info->bytes_per_second = info->freq * info->bytes_per_frame;
     info->swap_endianness = (as->endianness != AUDIO_HOST_ENDIANNESS);
 }
 
@@ -344,26 +344,25 @@ void audio_pcm_info_clear_buf (struct audio_pcm_info *info, void *buf, int len)
     }
 
     if (info->sign) {
-        memset (buf, 0x00, len << info->shift);
+        memset(buf, 0x00, len * info->bytes_per_frame);
     }
     else {
         switch (info->bits) {
         case 8:
-            memset (buf, 0x80, len << info->shift);
+            memset(buf, 0x80, len * info->bytes_per_frame);
             break;
 
         case 16:
             {
                 int i;
                 uint16_t *p = buf;
-                int shift = info->nchannels - 1;
                 short s = INT16_MAX;
 
                 if (info->swap_endianness) {
                     s = bswap16 (s);
                 }
 
-                for (i = 0; i < len << shift; i++) {
+                for (i = 0; i < len * info->nchannels; i++) {
                     p[i] = s;
                 }
             }
@@ -373,14 +372,13 @@ void audio_pcm_info_clear_buf (struct audio_pcm_info *info, void *buf, int len)
             {
                 int i;
                 uint32_t *p = buf;
-                int shift = info->nchannels - 1;
                 int32_t s = INT32_MAX;
 
                 if (info->swap_endianness) {
                     s = bswap32 (s);
                 }
 
-                for (i = 0; i < len << shift; i++) {
+                for (i = 0; i < len * info->nchannels; i++) {
                     p[i] = s;
                 }
             }
@@ -558,7 +556,7 @@ static void audio_pcm_hw_clip_out(HWVoiceOut *hw, void *pcm_buf, size_t len)
 
     while (len) {
         st_sample *src = hw->mix_buf->samples + pos;
-        uint8_t *dst = advance(pcm_buf, clipped << hw->info.shift);
+        uint8_t *dst = advance(pcm_buf, clipped * hw->info.bytes_per_frame);
         size_t samples_till_end_of_buf = hw->mix_buf->size - pos;
         size_t samples_to_clip = MIN(len, samples_till_end_of_buf);
 
@@ -607,7 +605,7 @@ static size_t audio_pcm_sw_read(SWVoiceIn *sw, void *buf, size_t size)
         return 0;
     }
 
-    samples = size >> sw->info.shift;
+    samples = size / sw->info.bytes_per_frame;
     if (!live) {
         return 0;
     }
@@ -642,7 +640,7 @@ static size_t audio_pcm_sw_read(SWVoiceIn *sw, void *buf, size_t size)
 
     sw->clip (buf, sw->buf, ret);
     sw->total_hw_samples_acquired += total;
-    return ret << sw->info.shift;
+    return ret * sw->info.bytes_per_frame;
 }
 
 /*
@@ -715,7 +713,7 @@ static size_t audio_pcm_sw_write(SWVoiceOut *sw, void *buf, size_t size)
     }
 
     wpos = (sw->hw->mix_buf->pos + live) % hwsamples;
-    samples = size >> sw->info.shift;
+    samples = size / sw->info.bytes_per_frame;
 
     dead = hwsamples - live;
     swlim = ((int64_t) dead << 32) / sw->ratio;
@@ -759,13 +757,13 @@ static size_t audio_pcm_sw_write(SWVoiceOut *sw, void *buf, size_t size)
     dolog (
         "%s: write size %zu ret %zu total sw %zu\n",
         SW_NAME (sw),
-        size >> sw->info.shift,
+        size / sw->info.bytes_per_frame,
         ret,
         sw->total_hw_samples_mixed
         );
 #endif
 
-    return ret << sw->info.shift;
+    return ret * sw->info.bytes_per_frame;
 }
 
 #ifdef DEBUG_AUDIO
@@ -882,7 +880,7 @@ size_t AUD_read(SWVoiceIn *sw, void *buf, size_t size)
 
 int AUD_get_buffer_size_out (SWVoiceOut *sw)
 {
-    return sw->hw->mix_buf->size << sw->hw->info.shift;
+    return sw->hw->mix_buf->size * sw->hw->info.bytes_per_frame;
 }
 
 void AUD_set_active_out (SWVoiceOut *sw, int on)
@@ -998,10 +996,10 @@ static size_t audio_get_avail (SWVoiceIn *sw)
     ldebug (
         "%s: get_avail live %d ret %" PRId64 "\n",
         SW_NAME (sw),
-        live, (((int64_t) live << 32) / sw->ratio) << sw->info.shift
+        live, (((int64_t) live << 32) / sw->ratio) * sw->info.bytes_per_frame
         );
 
-    return (((int64_t) live << 32) / sw->ratio) << sw->info.shift;
+    return (((int64_t) live << 32) / sw->ratio) * sw->info.bytes_per_frame;
 }
 
 static size_t audio_get_free(SWVoiceOut *sw)
@@ -1025,10 +1023,11 @@ static size_t audio_get_free(SWVoiceOut *sw)
 #ifdef DEBUG_OUT
     dolog ("%s: get_free live %d dead %d ret %" PRId64 "\n",
            SW_NAME (sw),
-           live, dead, (((int64_t) dead << 32) / sw->ratio) << sw->info.shift);
+           live, dead, (((int64_t) dead << 32) / sw->ratio) *
+           sw->info.bytes_per_frame);
 #endif
 
-    return (((int64_t) dead << 32) / sw->ratio) << sw->info.shift;
+    return (((int64_t) dead << 32) / sw->ratio) * sw->info.bytes_per_frame;
 }
 
 static void audio_capture_mix_and_clear(HWVoiceOut *hw, size_t rpos,
@@ -1047,7 +1046,7 @@ static void audio_capture_mix_and_clear(HWVoiceOut *hw, size_t rpos,
             while (n) {
                 size_t till_end_of_hw = hw->mix_buf->size - rpos2;
                 size_t to_write = MIN(till_end_of_hw, n);
-                size_t bytes = to_write << hw->info.shift;
+                size_t bytes = to_write * hw->info.bytes_per_frame;
                 size_t written;
 
                 sw->buf = hw->mix_buf->samples + rpos2;
@@ -1082,10 +1081,11 @@ static size_t audio_pcm_hw_run_out(HWVoiceOut *hw, size_t live)
             return clipped + live;
         }
 
-        decr = MIN(size >> hw->info.shift, live);
+        decr = MIN(size / hw->info.bytes_per_frame, live);
         audio_pcm_hw_clip_out(hw, buf, decr);
-        proc = hw->pcm_ops->put_buffer_out(hw, buf, decr << hw->info.shift) >>
-            hw->info.shift;
+        proc = hw->pcm_ops->put_buffer_out(hw, buf,
+                                           decr * hw->info.bytes_per_frame) /
+            hw->info.bytes_per_frame;
 
         live -= proc;
         clipped += proc;
@@ -1234,16 +1234,16 @@ static size_t audio_pcm_hw_run_in(HWVoiceIn *hw, size_t samples)
 
     while (samples) {
         size_t proc;
-        size_t size = samples << hw->info.shift;
+        size_t size = samples * hw->info.bytes_per_frame;
         void *buf = hw->pcm_ops->get_buffer_in(hw, &size);
 
-        assert((size & hw->info.align) == 0);
+        assert(size % hw->info.bytes_per_frame == 0);
         if (size == 0) {
             hw->pcm_ops->put_buffer_in(hw, buf, size);
             break;
         }
 
-        proc = MIN(size >> hw->info.shift,
+        proc = MIN(size / hw->info.bytes_per_frame,
                    conv_buf->size - conv_buf->pos);
 
         hw->conv(conv_buf->samples + conv_buf->pos, buf, proc);
@@ -1251,7 +1251,7 @@ static size_t audio_pcm_hw_run_in(HWVoiceIn *hw, size_t samples)
 
         samples -= proc;
         conv += proc;
-        hw->pcm_ops->put_buffer_in(hw, buf, proc << hw->info.shift);
+        hw->pcm_ops->put_buffer_in(hw, buf, proc * hw->info.bytes_per_frame);
     }
 
     return conv;
@@ -1325,7 +1325,7 @@ static void audio_run_capture (AudioState *s)
 
             for (cb = cap->cb_head.lh_first; cb; cb = cb->entries.le_next) {
                 cb->ops.capture (cb->opaque, cap->buf,
-                                 to_capture << hw->info.shift);
+                                 to_capture * hw->info.bytes_per_frame);
             }
             rpos = (rpos + to_capture) % hw->mix_buf->size;
             live -= to_capture;
@@ -1378,7 +1378,7 @@ void *audio_generic_get_buffer_in(HWVoiceIn *hw, size_t *size)
     ssize_t start;
 
     if (unlikely(!hw->buf_emul)) {
-        size_t calc_size = hw->conv_buf->size << hw->info.shift;
+        size_t calc_size = hw->conv_buf->size * hw->info.bytes_per_frame;
         hw->buf_emul = g_malloc(calc_size);
         hw->size_emul = calc_size;
         hw->pos_emul = hw->pending_emul = 0;
@@ -1414,7 +1414,7 @@ void audio_generic_put_buffer_in(HWVoiceIn *hw, void *buf, size_t size)
 void *audio_generic_get_buffer_out(HWVoiceOut *hw, size_t *size)
 {
     if (unlikely(!hw->buf_emul)) {
-        size_t calc_size = hw->mix_buf->size << hw->info.shift;
+        size_t calc_size = hw->mix_buf->size * hw->info.bytes_per_frame;
 
         hw->buf_emul = g_malloc(calc_size);
         hw->size_emul = calc_size;
@@ -1833,7 +1833,7 @@ CaptureVoiceOut *AUD_add_capture(
 
         audio_pcm_init_info (&hw->info, as);
 
-        cap->buf = g_malloc0_n(hw->mix_buf->size, 1 << hw->info.shift);
+        cap->buf = g_malloc0_n(hw->mix_buf->size, hw->info.bytes_per_frame);
 
         hw->clip = mixeng_clip
             [hw->info.nchannels == 2]
@@ -2153,14 +2153,14 @@ size_t audio_rate_get_bytes(struct audio_pcm_info *info, RateCtl *rate,
     now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
     ticks = now - rate->start_ticks;
     bytes = muldiv64(ticks, info->bytes_per_second, NANOSECONDS_PER_SECOND);
-    samples = (bytes - rate->bytes_sent) >> info->shift;
+    samples = (bytes - rate->bytes_sent) / info->bytes_per_frame;
     if (samples < 0 || samples > 65536) {
         AUD_log(NULL, "Resetting rate control (%" PRId64 " samples)\n", samples);
         audio_rate_start(rate);
         samples = 0;
     }
 
-    ret = MIN(samples << info->shift, bytes_avail);
+    ret = MIN(samples * info->bytes_per_frame, bytes_avail);
     rate->bytes_sent += ret;
     return ret;
 }