Index: apps/talk.c
===================================================================
RCS file: /cvsroot/rockbox/apps/talk.c,v
retrieving revision 1.46
diff -u -r1.46 talk.c
--- apps/talk.c	25 May 2006 12:45:57 -0000	1.46
+++ apps/talk.c	21 Jul 2006 14:49:41 -0000
@@ -45,6 +45,7 @@
 #define QUEUE_MASK (QUEUE_SIZE-1)
 const char* const dir_thumbnail_name = "_dirname.talk";
 const char* const file_thumbnail_ext = ".talk";
+#define MAX_THUMBNAIL_BUFSIZE 32768
 
 /***************** Functional Macros *****************/
 
@@ -173,11 +174,7 @@
            == offsetof(struct voicefile, index))
     {
         p_voicefile = (struct voicefile*)audiobuf;
-
-        /* thumbnail buffer is the remaining space behind */
-        p_thumbnail = audiobuf + file_size;
-        p_thumbnail += (long)p_thumbnail % 2; /* 16-bit align */
-        size_for_thumbnail = audiobufend - p_thumbnail;
+        audiobuf += file_size;
     }
     else
        goto load_err;
@@ -198,7 +195,7 @@
     cpu_boost(true);
     buf = (unsigned char *)(&p_voicefile->index) +
         (p_voicefile->id1_max + p_voicefile->id2_max) * sizeof(struct clip_entry);
-    length = file_size - (buf - audiobuf);
+    length = file_size - (buf - (unsigned char *) p_voicefile);
                
     for (i = 0; i < length; i++)
     {
@@ -216,7 +213,7 @@
     load_size = (p_voicefile->id1_max + p_voicefile->id2_max)
                 * sizeof(struct clip_entry);
     got_size = read(filehandle, 
-                    audiobuf + offsetof(struct voicefile, index), load_size);
+                    (unsigned char *) p_voicefile + offsetof(struct voicefile, index), load_size);
     if (got_size != load_size) /* read error */
        goto load_err;
 #else
@@ -280,7 +277,7 @@
     }
     else if (p_silence != NULL            /* silence clip available */
              && p_lastclip != p_silence   /* previous clip wasn't silence */
-             && p_lastclip < p_thumbnail) /* ..and not a thumbnail */
+             && (p_thumbnail == NULL || p_lastclip < p_thumbnail)) /* ..and not a thumbnail */
     {   /* add silence clip when queue runs empty playing a voice clip */
         queue[queue_write].buf = p_silence;
         queue[queue_write].len = silence_len;
@@ -424,7 +421,7 @@
     clipsize = p_voicefile->index[id].size;
     if (clipsize == 0) /* clip not included in voicefile */
         return NULL;
-    clipbuf = audiobuf + p_voicefile->index[id].offset;
+    clipbuf = (unsigned char *) p_voicefile + p_voicefile->index[id].offset;
 
 #ifdef HAVE_MMC /* dynamic loading, on demand */
     if (!(clipsize & LOADED_MASK))
@@ -451,8 +448,8 @@
 {
     queue_write = queue_read = 0; /* reset the queue */
     p_voicefile = NULL; /* indicate no voicefile (trashed) */
-    p_thumbnail = audiobuf; /*  whole space for thumbnail */
-    size_for_thumbnail = audiobufend - audiobuf;
+    p_thumbnail = NULL; /* no thumbnail buffer allocated */
+    size_for_thumbnail = 0;
     p_silence = NULL; /* pause clip not accessible */
 }
 
@@ -566,6 +563,17 @@
     if (audio_status()) /* busy, buffer in use */
         return -1; 
 
+    /* Allocate a thumbnail buffer if required */
+    if (p_thumbnail == NULL)
+    {
+        p_thumbnail = audiobuf;
+        p_thumbnail += (long)p_thumbnail % 2; /* 16-bit align */
+        size_for_thumbnail = audiobufend - audiobuf;
+        if (size_for_thumbnail > MAX_THUMBNAIL_BUFSIZE)
+            size_for_thumbnail = MAX_THUMBNAIL_BUFSIZE;
+        audiobuf = p_thumbnail + size_for_thumbnail;
+    }
+
     if (p_thumbnail == NULL || size_for_thumbnail <= 0)
         return -1;
 
@@ -587,7 +595,7 @@
 
     /* ToDo: find audio, skip ID headers and trailers */
 
-    if (size)
+    if (size != 0 && size != size_for_thumbnail)  /* Don't play missing or truncated clips */
     {
 #if CONFIG_CODEC != SWCODEC
         bitswap(p_thumbnail, size);