Add ability to skip unreadable sectors

[hrw]

I have "Toy Story 2" disk which is both CSS scrambled and filled with unreadable sectors in /VIDEO_TS/VTS_01_1.VOB file.

Did some quick hack to make dvdread ignore read errors and looks like it gets further with reading.

11:20 hrw@puchatek:dvdread$ git diff
diff --git a/dvdread.c b/dvdread.c
index 00f47c1..35bbc5a 100644
--- a/dvdread.c
+++ b/dvdread.c
@@ -133,8 +133,8 @@ int main(int argc, char *argv[]) {
             r = dvdcss_read(dvdcss, p_buffer, 1, DVDCSS_READ_DECRYPT);
         } else r = dvdcss_read(dvdcss, p_buffer, 1, DVDCSS_NOFLAGS);
         if (r == 0) goto EOFDVD;
-        if (r != 1) goto CSSERR;
-        if (!dumpsector(p_buffer)) goto STDERR;
+//        if (r != 1) goto CSSERR;
+        if (!dumpsector(p_buffer)) fprintf(stderr, "error reading sector\n");//goto STDERR;
     }
 EOFDVD:
     fprintf(stderr, "end of file %s\n", argv[1]);

Will add comments once it finish dumping disk (hope it will take only hours).

[hrw]

Disk got dumped properly.