Replace the amiga ahi driver with a working one.

Based on a MikMod driver written by Szilard Biro, which was loosely
based on an old AmigaOS4 version by Fredrik Wikstrom.

src/sound_ahi.c

@@ -1,59 +1,128 @@
 /* Amiga AHI driver for Extended Module Player
- * Copyright (C) 2007 Lorence Lombardo
+ * Based on a MikMod driver written by Szilard Biro, which was loosely
+ * based on an old AmigaOS4 version by Fredrik Wikstrom.
  *
  * This file is part of the Extended Module Player and is distributed
  * under the terms of the GNU General Public License. See the COPYING
  * file for more information.
  */
 
+#ifdef __amigaos4__
+#define __USE_INLINE__
+#endif
+
 #include <stdlib.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
 #include <string.h>
 #include "sound.h"
 
-static int fd;
+#include <proto/exec.h>
+#include <proto/dos.h>
+#include <devices/ahi.h>
 
-static int init(struct options *options)
-{
-	char **parm = options->driver_parm;
-	char outfile[256];
-	int nch = options->format & XMP_FORMAT_MONO ? 1 : 2;
-	int res = options->format & XMP_FORMAT_8BIT ? 8 : 16;
-	int bsize = options->rate * nch * res / 4;
-	
-	parm_init(parm);
-	chkparm1("buffer", bsize = strtoul(token, NULL, 0));
-	parm_end();
-
-	sprintf(outfile, "AUDIO:B/%d/F/%d/C/%d/BUFFER/%d",
-				res, options->rate, nch, bsize);
-
-	fd = open(outfile, O_WRONLY);
-	if (fd < 0)
-		return -1;
-
-	return 0;
+#define BUFFERSIZE (4 << 10)
+
+static struct MsgPort *AHImp = NULL;
+static struct AHIRequest *AHIReq[2] = { NULL, NULL };
+static int active = 0;
+static signed char *AHIBuf[2] = { NULL, NULL };
+
+static void closeLibs(void) {
+    if (AHIReq[1]) {
+        AHIReq[0]->ahir_Link = NULL; /* in case we are linked to req[0] */
+        if (!CheckIO((struct IORequest *) AHIReq[1])) {
+            AbortIO((struct IORequest *) AHIReq[1]);
+            WaitIO((struct IORequest *) AHIReq[1]);
+        }
+        FreeVec(AHIReq[1]);
+        AHIReq[1] = NULL;
+    }
+    if (AHIReq[0]) {
+        if (!CheckIO((struct IORequest *) AHIReq[0])) {
+            AbortIO((struct IORequest *) AHIReq[0]);
+            WaitIO((struct IORequest *) AHIReq[0]);
+        }
+        if (AHIReq[0]->ahir_Std.io_Device) {
+            CloseDevice((struct IORequest *) AHIReq[0]);
+            AHIReq[0]->ahir_Std.io_Device = NULL;
+        }
+        DeleteIORequest((struct IORequest *) AHIReq[0]);
+        AHIReq[0] = NULL;
+    }
+    if (AHImp) {
+        DeleteMsgPort(AHImp);
+        AHImp = NULL;
+    }
+    if (AHIBuf[0]) {
+        FreeVec(AHIBuf[0]);
+        AHIBuf[0] = NULL;
+    }
+    if (AHIBuf[1]) {
+        FreeVec(AHIBuf[1]);
+        AHIBuf[1] = NULL;
+    }
 }
 
-static void play(void *b, int i)
-{
-	int j;
-
-	while (i) {
-		if ((j = write(fd, b, i)) > 0) {
-			i -= j;
-			b = (char *)b + j;
-		} else
-			break;
-	}
+static int init(struct options *options) {
+    AHImp = CreateMsgPort();
+    if (AHImp) {
+        AHIReq[0] = (struct AHIRequest *)CreateIORequest(AHImp, sizeof(struct AHIRequest));
+        if (AHIReq[0]) {
+            AHIReq[0]->ahir_Version = 4;
+            AHIReq[1] = AllocVec(sizeof(struct AHIRequest), MEMF_PUBLIC);
+            if (AHIReq[1]) {
+                if (!OpenDevice(AHINAME, AHI_DEFAULT_UNIT, (struct IORequest *)AHIReq[0], 0)) {
+                    AHIReq[0]->ahir_Std.io_Command = CMD_WRITE;
+                    AHIReq[0]->ahir_Std.io_Data = NULL;
+                    AHIReq[0]->ahir_Std.io_Offset = 0;
+                    AHIReq[0]->ahir_Frequency = options->rate;
+                    AHIReq[0]->ahir_Type = (options->format & XMP_FORMAT_8BIT)?
+                                            ((options->format & XMP_FORMAT_MONO)? AHIST_M8S  : AHIST_S8S ) :
+                                            ((options->format & XMP_FORMAT_MONO)? AHIST_M16S : AHIST_S16S);
+                    AHIReq[0]->ahir_Volume = 0x10000;
+                    AHIReq[0]->ahir_Position = 0x8000;
+
+                    CopyMem(AHIReq[0], AHIReq[1], sizeof(struct AHIRequest));
+
+                    AHIBuf[0] = AllocVec(BUFFERSIZE, MEMF_PUBLIC | MEMF_CLEAR);
+                    if (AHIBuf[0]) {
+                        AHIBuf[1] = AllocVec(BUFFERSIZE, MEMF_PUBLIC | MEMF_CLEAR);
+                        if (AHIBuf[1]) {
+                            /* driver is initialized before calling libxmp, so this is OK : */
+                            options->format &= ~XMP_FORMAT_UNSIGNED;/* no unsigned with AHI */
+                            return 0;
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    closeLibs();
+    return -1;
 }
 
-static void deinit(void)
-{
-	close(fd);
+static void deinit(void) {
+    closeLibs();
+}
+
+static void play(void *b, int len) {
+    signed char *in = (signed char *)b;
+    int chunk;
+    while (len > 0) {
+        if (AHIReq[active]->ahir_Std.io_Data) {
+            WaitIO((struct IORequest *) AHIReq[active]);
+        }
+        chunk = (len < BUFFERSIZE)? len : BUFFERSIZE;
+        memcpy(AHIBuf[active], in, chunk);
+        len -= chunk;
+        in += chunk;
+
+        AHIReq[active]->ahir_Std.io_Data = AHIBuf[active];
+        AHIReq[active]->ahir_Std.io_Length = chunk;
+        AHIReq[active]->ahir_Link = !CheckIO((struct IORequest *) AHIReq[active ^ 1]) ? AHIReq[active ^ 1] : NULL;
+        SendIO((struct IORequest *)AHIReq[active]);
+        active ^= 1;
+    }
 }
 
 static void flush(void)
@@ -68,15 +137,10 @@ static void onresume(void)
 {
 }
 
-static const char *const help[] = {
-	"buffer=val", "Audio buffer size",
-	NULL
-};
-
 struct sound_driver sound_ahi = {
 	"ahi",
 	"Amiga AHI audio",
-	help,
+	NULL,
 	init,
 	deinit,
 	play,