ref: 023a0ce70099b0cc01c0956377def3238a6a947a
dir: /kern/devaudio-sun.c/
/* * Sun */ #include <sys/ioctl.h> #include <sys/audio.h> #include "u.h" #include "lib.h" #include "dat.h" #include "fns.h" #include "error.h" #include "devaudio.h" enum { Channels = 2, Rate = 44100, Bits = 16, }; static char* afn = 0; static char* cfn = 0; static int afd = -1; static int cfd = -1; static int speed = Rate; static int needswap = -1; static void audiodevinit(void) { uchar *p; ushort leorder; if ((afn = getenv("AUDIODEV")) == nil) afn = "/dev/audio"; cfn = (char*)malloc(strlen(afn) + 3 + 1); if(cfn == nil) panic("out of memory"); strcpy(cfn, afn); strcat(cfn, "ctl"); /* * Plan 9 /dev/audio is always little endian; * solaris /dev/audio seems to expect native byte order, * so on big endian machine (like sparc) we have to swap. */ leorder = (ushort) 0x0100; p = (uchar*)&leorder; if (p[0] == 0 && p[1] == 1) { /* little-endian: nothing to do */ needswap = 0; } else { /* big-endian: translate Plan 9 little-endian */ needswap = 1; } } /* maybe this should return -1 instead of sysfatal */ void audiodevopen(void) { audio_info_t info; struct audio_device ad; if (afn == nil || cfn == nil) audiodevinit(); if((afd = open(afn, O_WRONLY)) < 0) goto err; if(cfd < 0 && (cfd = open(cfn, O_RDWR)) < 0) goto err; AUDIO_INITINFO(&info); info.play.precision = Bits; info.play.channels = Channels; info.play.sample_rate = speed; info.play.encoding = AUDIO_ENCODING_LINEAR; if(ioctl(afd, AUDIO_SETINFO, &info) < 0) goto err; return; err: if(afd >= 0) close(afd); afd = -1; if(cfd >= 0) close(cfd); cfd = -1; oserror(); } void audiodevclose(void) { if(afd >= 0) close(afd); if(cfd >= 0) close(cfd); afd = -1; cfd = -1; } static double fromsun(double val, double min, double max) { return (val-min) / (max-min); } static double tosun(double val, double min, double max) { return val*(max-min) + min; } static void setvolbal(double left, double right) { audio_info_t info; double vol, bal; if (left < 0 || right < 0) { /* should not happen */ return; } else if (left == right) { vol = tosun(left/100.0, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN); bal = AUDIO_MID_BALANCE; } else if (left < right) { vol = tosun(right/100.0, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN); bal = tosun(1.0 - left/right, AUDIO_MID_BALANCE, AUDIO_RIGHT_BALANCE); } else if (right < left) { vol = tosun(left/100.0, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN); bal = tosun(1.0 - right/left, AUDIO_MID_BALANCE, AUDIO_LEFT_BALANCE); } AUDIO_INITINFO(&info); info.play.gain = (long)(vol+0.5); info.play.balance = (long)(bal+0.5); if(ioctl(cfd, AUDIO_SETINFO, &info) < 0) oserror(); } static void getvolbal(int *left, int *right) { audio_info_t info; double gain, bal, vol, l, r; AUDIO_INITINFO(&info); if (ioctl(cfd, AUDIO_GETINFO, &info) < 0) oserror(); gain = info.play.gain; bal = info.play.balance; vol = fromsun(gain, AUDIO_MIN_GAIN, AUDIO_MAX_GAIN) * 100.0; if (bal == AUDIO_MID_BALANCE) { l = r = vol; } else if (bal < AUDIO_MID_BALANCE) { l = vol; r = vol * (1.0 - fromsun(bal, AUDIO_MID_BALANCE, AUDIO_LEFT_BALANCE)); } else { r = vol; l = vol * (1.0 - fromsun(bal, AUDIO_MID_BALANCE, AUDIO_RIGHT_BALANCE)); } *left = (long)(l+0.5); *right = (long)(r+0.5); return; } void audiodevsetvol(int what, int left, int right) { audio_info_t info; ulong x; int l, r; if (afn == nil || cfn == nil) audiodevinit(); if(cfd < 0 && (cfd = open(cfn, O_RDWR)) < 0) { cfd = -1; oserror(); } if(what == Vspeed){ x = left; AUDIO_INITINFO(&info); info.play.sample_rate = x; if(ioctl(cfd, AUDIO_SETINFO, &info) < 0) oserror(); speed = x; return; } if(what == Vaudio){ getvolbal(&l, &r); if (left < 0) setvolbal(l, right); else if (right < 0) setvolbal(left, r); else setvolbal(left, right); return; } } void audiodevgetvol(int what, int *left, int *right) { audio_info_t info; if (afn == nil || cfn == nil) audiodevinit(); if(cfd < 0 && (cfd = open(cfn, O_RDWR)) < 0) { cfd = -1; oserror(); } switch(what) { case Vspeed: *left = *right = speed; break; case Vaudio: getvolbal(left, right); break; case Vtreb: case Vbass: *left = *right = 50; break; default: *left = *right = 0; } } static uchar *buf = 0; static int nbuf = 0; int audiodevwrite(void *v, int n) { int i, m, tot; uchar *p; if (needswap) { if (nbuf < n) { buf = (uchar*)erealloc(buf, n); if(buf == nil) panic("out of memory"); nbuf = n; } p = (uchar*)v; for(i=0; i+1<n; i+=2) { buf[i] = p[i+1]; buf[i+1] = p[i]; } p = buf; } else p = (uchar*)v; for(tot=0; tot<n; tot+=m) if((m = write(afd, p+tot, n-tot)) <= 0) oserror(); return tot; } int audiodevread(void *v, int n) { error("no reading"); return -1; }