cdriso: handle pregap read/play

diff --git a/libpcsxcore/cdriso.c b/libpcsxcore/cdriso.c
index cf1b363..6df8b67 100644 (file)
--- a/libpcsxcore/cdriso.c
+++ b/libpcsxcore/cdriso.c
@@ -38,6 +38,7 @@ static FILE *subHandle = NULL;
 
 static boolean subChanMixed = FALSE;
 static boolean subChanRaw = FALSE;
+static boolean subChanMissing = FALSE;
 
 static unsigned char cdbuffer[DATA_SIZE];
 static unsigned char subbuffer[SUB_FRAMESIZE];
@@ -56,6 +57,11 @@ static boolean playing = FALSE;
 static boolean cddaBigEndian = FALSE;
 static unsigned int cddaCurOffset = 0;
 static unsigned int cddaStartOffset;
+/* Frame offset into CD image where pregap data would be found if it was there.
+ * If a game seeks there we must *not* return subchannel data since it's
+ * not in the CD image, so that cdrom code can fake subchannel data instead.
+ * XXX: there could be multiple pregaps but PSX dumps only have one? */
+static unsigned int pregapOffset;
 
 char* CALLBACK CDR__getDriveLetter(void);
 long CALLBACK CDR__configure(void);
@@ -368,6 +374,10 @@ static int parsetoc(const char *isofile) {
                        sscanf(linebuf, "ZERO AUDIO RW_RAW %8s", time);
                        tok2msf((char *)&time, dummy);
                        sector_offs += msf2sec(dummy);
+                       if (numtracks > 1) {
+                               t = ti[numtracks - 1].start_offset;
+                               pregapOffset = t + msf2sec(ti[numtracks - 1].length);
+                       }
                }
        }
 
@@ -473,12 +483,15 @@ static int parsecue(const char *isofile) {
                                t = msf2sec(ti[numtracks].start) - msf2sec(ti[numtracks - 1].start);
                                sec2msf(t, ti[numtracks - 1].length);
                        }
+                       if (numtracks > 1 && pregapOffset == -1)
+                               pregapOffset = ti[numtracks].start_offset;
                }
                else if (!strcmp(token, "PREGAP")) {
                        if (sscanf(linebuf, " PREGAP %8s", time) == 1) {
                                tok2msf(time, dummy);
                                sector_offs += msf2sec(dummy);
                        }
+                       pregapOffset = -1; // mark to fill track start_offset
                }
                else if (!strcmp(token, "FILE")) {
                        sscanf(linebuf, " FILE \"%[^\"]\"", tmpb);
@@ -662,21 +675,27 @@ static int parsemds(const char *isofile) {
                ti[i].start[1] = fgetc(fi);
                ti[i].start[2] = fgetc(fi);
 
-               // get the track length
                fread(&extra_offset, 1, sizeof(unsigned int), fi);
                extra_offset = SWAP32(extra_offset);
 
-               fseek(fi, extra_offset + 4, SEEK_SET);
-               fread(&l, 1, sizeof(unsigned int), fi);
-               l = SWAP32(l);
-               sec2msf(l, ti[i].length);
-
                // get track start offset (in .mdf)
                fseek(fi, offset + 0x28, SEEK_SET);
                fread(&l, 1, sizeof(unsigned int), fi);
                l = SWAP32(l);
                ti[i].start_offset = l / CD_FRAMESIZE_RAW;
 
+               // get pregap
+               fseek(fi, extra_offset, SEEK_SET);
+               fread(&l, 1, sizeof(unsigned int), fi);
+               l = SWAP32(l);
+               if (l != 0 && i > 1)
+                       pregapOffset = ti[i].start_offset;
+
+               // get the track length
+               fread(&l, 1, sizeof(unsigned int), fi);
+               l = SWAP32(l);
+               sec2msf(l, ti[i].length);
+
                offset += 0x50;
        }
 
@@ -753,6 +772,8 @@ static long CALLBACK ISOopen(void) {
        cddaBigEndian = FALSE;
        subChanMixed = FALSE;
        subChanRaw = FALSE;
+       subChanMixed = FALSE;
+       pregapOffset = 0;
 
        if (parsecue(GetIsoFile()) == 0) {
                SysPrintf("[+cue]");
@@ -898,6 +919,15 @@ static long CALLBACK ISOreadTrack(unsigned char *time) {
                return -1;
        }
 
+       if (pregapOffset) {
+               subChanMissing = FALSE;
+               if (sector >= pregapOffset) {
+                       sector -= 2 * 75;
+                       if (sector < pregapOffset)
+                               subChanMissing = TRUE;
+               }
+       }
+
        if (subChanMixed) {
                fseek(cdHandle, sector * (CD_FRAMESIZE_RAW + SUB_FRAMESIZE) + 12, SEEK_SET);
                fread(cdbuffer, 1, DATA_SIZE, cdHandle);
@@ -953,6 +983,11 @@ static long CALLBACK ISOplay(unsigned char *time) {
        cddaStartOffset = abs_sect - file_sect;
        cddaHandle = ti[i].handle;
 
+       if (pregapOffset && (unsigned int)(pregapOffset - file_sect) < 2 * 75) {
+               // get out of the missing pregap to avoid noise
+               file_sect = pregapOffset;
+       }
+
        if (SPU_playCDDAchannel != NULL) {
                if (subChanMixed) {
                        startCDDA(file_sect * (CD_FRAMESIZE_RAW + SUB_FRAMESIZE));
@@ -974,7 +1009,7 @@ static long CALLBACK ISOstop(void) {
 
 // gets subchannel data
 static unsigned char* CALLBACK ISOgetBufferSub(void) {
-       if (subHandle != NULL || subChanMixed) {
+       if ((subHandle != NULL || subChanMixed) && !subChanMissing) {
                return subbuffer;
        }