Fixed bug 3484 - DSP driver does not detect /dev/dsp0

Tobias Kortkamp

using SDL 2.0.5 (and a repository checkout) on FreeBSD 11.0 I get this output
from testaudioinfo with SDL_AUDIODRIVER=dsp:

INFO: Found 8 output devices:
INFO:   0: /dev/dsp
INFO:   1: /dev/dsp1
INFO:   2: /dev/dsp2
INFO:   3: /dev/dsp3
INFO:   4: /dev/dsp4
INFO:   5: /dev/dsp5
INFO:   6: /dev/dsp6
INFO:   7: /dev/dsp7
INFO:
INFO: Found 3 capture devices:
INFO:   0: /dev/dsp
INFO:   1: /dev/dsp4
INFO:   2: /dev/dsp5
INFO:

This is /dev/sndstat:

Installed devices:
pcm0: <NVIDIA (0x0040) (HDMI/DP 8ch)> (play)
pcm1: <NVIDIA (0x0040) (HDMI/DP 8ch)> (play)
pcm2: <NVIDIA (0x0040) (HDMI/DP 8ch)> (play)
pcm3: <NVIDIA (0x0040) (HDMI/DP 8ch)> (play)
pcm4: <Realtek ALC887 (Rear Analog 7.1/2.0)> (play/rec)
pcm5: <Realtek ALC887 (Front Analog)> (play/rec) default
pcm6: <Realtek ALC887 (Rear Digital)> (play)
pcm7: <Realtek ALC887 (Onboard Digital)> (play)
No devices installed from userspace.

I'd expect to find /dev/dsp0 in the output device list.  It's not detected
because of a a small logic error in SDL_audiodev.c (see attached patch).

With the patch applied I get this which is what I'd expect:

INFO: Found 9 output devices:
INFO:   0: /dev/dsp
INFO:   1: /dev/dsp0
INFO:   2: /dev/dsp1
INFO:   3: /dev/dsp2
INFO:   4: /dev/dsp3
INFO:   5: /dev/dsp4
INFO:   6: /dev/dsp5
INFO:   7: /dev/dsp6
INFO:   8: /dev/dsp7

src/audio/SDL_audiodev.c

@@ -103,9 +103,10 @@ SDL_EnumUnixAudioDevices_Internal(const int iscapture, const int classic, int (*
 
     if (SDL_strlen(audiodev) < (sizeof(audiopath) - 3)) {
         int instance = 0;
-        while (instance++ <= 64) {
+        while (instance <= 64) {
             SDL_snprintf(audiopath, SDL_arraysize(audiopath),
                          "%s%d", audiodev, instance);
+            instance++;
             test_device(iscapture, audiopath, flags, test);
         }
     }