Added CD-ROM .ISO support. Patch from RichardG867.

Minor cleanup to CD-ROM handling.

src/cdrom-iso.c

@@ -0,0 +1,248 @@
+/*ISO CD-ROM support*/
+
+#include "ibm.h"
+#include "ide.h"
+#include "cdrom-iso.h"
+#include <sys/stat.h>
+
+static ATAPI iso_atapi;
+
+static uint32_t last_block = 0;
+static uint64_t image_size = 0;
+static int iso_inited = 0;
+char iso_path[1024];
+static FILE *iso_image = NULL;
+static int iso_changed = 0;
+
+static uint32_t iso_cd_pos = 0, iso_cd_end = 0;
+
+void iso_audio_callback(int16_t *output, int len)
+{
+        memset(output, 0, len * 2);
+        return;
+}
+
+void iso_audio_stop()
+{
+        pclog("iso_audio_stop stub\n");
+}
+
+static int get_track_nr(uint32_t pos)
+{
+        pclog("get_track_nr stub\n");
+        return 0;
+}
+
+static void iso_playaudio(uint32_t pos, uint32_t len, int ismsf)
+{
+        pclog("iso_playaudio stub\n");
+        return;
+}
+
+static void iso_pause(void)
+{
+        pclog("iso_pause stub\n");
+        return;
+}
+
+static void iso_resume(void)
+{
+        pclog("iso_resume stub\n");
+        return;
+}
+
+static void iso_stop(void)
+{
+        pclog("iso_stop stub\n");
+        return;
+}
+
+static void iso_seek(uint32_t pos)
+{
+        pclog("iso_seek stub\n");
+        return;
+}
+
+static int iso_ready(void)
+{
+	if (iso_changed)
+	{
+		iso_changed = 0;
+		return 0;
+	}
+
+        return 1;
+}
+
+static uint8_t iso_getcurrentsubchannel(uint8_t *b, int msf)
+{
+        pclog("iso_getcurrentsubchannel stub\n");
+        return 0;
+}
+
+static void iso_eject(void)
+{
+        pclog("iso_eject stub\n");
+}
+
+static void iso_load(void)
+{
+        pclog("iso_load stub\n");
+}
+
+static void iso_readsector(uint8_t *b, int sector)
+{
+        if (!cdrom_drive) return;
+        fseek(iso_image,sector*2048,SEEK_SET);
+        fread(b,2048,1,iso_image);
+}
+
+static void lba_to_msf(uint8_t *buf, int lba)
+{
+        lba += 150;
+        buf[0] = (lba / 75) / 60;
+        buf[1] = (lba / 75) % 60;
+        buf[2] = lba & 75;
+}
+
+static int iso_readtoc(unsigned char *buf, unsigned char start_track, int msf, int maxlen, int single)
+{
+        uint8_t *q;
+        int len;
+
+        if (start_track > 1 && start_track != 0xaa)
+                return -1;
+        q = buf + 2;
+        *q++ = 1; /* first session */
+        *q++ = 1; /* last session */
+        if (start_track <= 1)
+        {
+                *q++ = 0; /* reserved */
+                *q++ = 0x14; /* ADR, control */
+                *q++ = 1;    /* track number */
+                *q++ = 0; /* reserved */
+                if (msf)
+                {
+                        *q++ = 0; /* reserved */
+                        lba_to_msf(q, 0);
+                        q += 3;
+                }
+                else
+                {
+                        /* sector 0 */
+                        *q++ = 0;
+                        *q++ = 0;
+                        *q++ = 0;
+                        *q++ = 0;
+                }
+        }
+        /* lead out track */
+        *q++ = 0; /* reserved */
+        *q++ = 0x16; /* ADR, control */
+        *q++ = 0xaa; /* track number */
+        *q++ = 0; /* reserved */
+        last_block = image_size >> 11;
+        if (msf)
+        {
+                *q++ = 0; /* reserved */
+                lba_to_msf(q, last_block);
+                q += 3;
+        }
+        else
+        {
+                *q++ = last_block >> 24;
+                *q++ = last_block >> 16;
+                *q++ = last_block >> 8;
+                *q++ = last_block;
+        }
+        len = q - buf;
+        buf[0] = (uint8_t)(((len-2) >> 8) & 0xff);
+        buf[1] = (uint8_t)((len-2) & 0xff);
+        return len;
+}
+
+static void iso_readtoc_session(unsigned char *buf, int msf, int maxlen)
+{
+        uint8_t *q;
+
+        q = buf + 2;
+        *q++ = 1; /* first session */
+        *q++ = 1; /* last session */
+
+        *q++ = 1; /* session number */
+        *q++ = 0x14; /* data track */
+        *q++ = 0; /* track number */
+        *q++ = 0xa0; /* lead-in */
+        *q++ = 0; /* min */
+        *q++ = 0; /* sec */
+        *q++ = 0; /* frame */
+        *q++ = 0;
+}
+
+static uint32_t iso_size()
+{
+        unsigned char b[4096];
+
+        atapi->readtoc(b, 0, 0, 4096, 0);
+    
+        return last_block;
+}
+
+void iso_reset()
+{
+}
+
+int iso_open(char *fn)
+{
+        struct stat st;
+
+        if (iso_image)
+                fclose(iso_image);
+
+	iso_changed = 1;
+
+        sprintf(iso_path, "%s", fn);
+        pclog("Path is %s\n", iso_path);
+
+        iso_image = fopen(iso_path, "rb");
+        atapi = &iso_atapi;
+    
+        stat(iso_path, &st);
+        image_size = st.st_size;
+    
+        return 0;
+}
+
+static void iso_close(void)
+{
+        if (iso_image)
+        {
+                fclose(iso_image);
+                iso_image = NULL;
+        }
+}
+
+static void iso_exit(void)
+{
+        iso_stop();
+        iso_inited = 0;
+        iso_close();
+}
+
+static ATAPI iso_atapi = 
+{
+        iso_ready,
+        iso_readtoc,
+        iso_readtoc_session,
+        iso_getcurrentsubchannel,
+        iso_readsector,
+        iso_playaudio,
+        iso_seek,
+        iso_load,
+        iso_eject,
+        iso_pause,
+        iso_resume,
+        iso_size,
+        iso_stop,
+        iso_exit
+};