amalgamation

[picodrive.git] / Pico / cd / buffering.c

diff --git a/Pico/cd/buffering.c b/Pico/cd/buffering.c
index 5afc6e8..15b3a86 100644 (file)
--- a/Pico/cd/buffering.c
+++ b/Pico/cd/buffering.c
@@ -1,3 +1,6 @@
+// Buffering handling
+// (c) Copyright 2007, Grazvydas "notaz" Ignotas
+
 #include "../PicoInt.h"
 
 //#include <stdlib.h>
@@ -47,9 +50,9 @@ void PicoCDBufferFree(void)
 
 
 /* this is a try to fight slow SD access of GP2X */
-void PicoCDBufferRead(void *dest, int lba)
+PICO_INTERNAL void PicoCDBufferRead(void *dest, int lba)
 {
-       int is_bin, offs, read_len;
+       int is_bin, offs, read_len, moved = 0;
        reads++;
 
        is_bin = Pico_mcd->TOC.Tracks[0].ftype == TYPE_BIN;
@@ -84,15 +87,21 @@ void PicoCDBufferRead(void *dest, int lba)
 
        if (lba < prev_lba && prev_lba - lba < PicoCDBuffers)
        {
-               dprintf("CD buffer move");
                read_len = prev_lba - lba;
+               dprintf("CD buffer move=%i, read_len=%i", PicoCDBuffers - read_len, read_len);
                memmove(cd_buffer + read_len*2048, cd_buffer, (PicoCDBuffers - read_len)*2048);
+               moved = 1;
        }
        else
        {
                read_len = PicoCDBuffers;
        }
 
+       if (PicoMessage != NULL && read_len >= 512)
+       {
+               PicoMessage("Buffering data...");
+       }
+
        if (is_bin)
        {
                int i;
@@ -108,5 +117,14 @@ void PicoCDBufferRead(void *dest, int lba)
        }
        memcpy32(dest, (int *) cd_buffer, 2048/4);
        prev_lba = lba;
+
+       if (moved)
+       {
+               /* file pointer must point to the same data in file, as would-be data after our buffer */
+               int where_seek;
+               lba += PicoCDBuffers;
+               where_seek = is_bin ? (lba * 2352 + 16) : (lba << 11);
+               pm_seek(Pico_mcd->TOC.Tracks[0].F, where_seek, SEEK_SET);
+       }
 }