configure: add --disable-crc option

Useful for fuzzing

2 files changed, 25 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index 33c88ab..588d2f5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -150,6 +150,17 @@ if test -z "$SIZE64"; then
         AC_MSG_WARN(No 64 bit type found on this platform!)
 fi
 
+AC_ARG_ENABLE([crc],
+    [AS_HELP_STRING([--disable-crc],
+                    [Disable CRC in the demuxer)])],,
+    [enable_crc=yes])
+
+AM_CONDITIONAL([DISABLE_CRC], [test "$enable_crc" = "no"])
+
+AS_IF([test "$enable_crc" = "no"],[
+  AC_DEFINE([DISABLE_CRC], [1], [Do not build with CRC])
+])
+
 dnl Checks for library functions.
 AC_FUNC_MEMCMP
 
diff --git a/src/framing.c b/src/framing.c
index 79fc715..ee29651 100644
--- a/src/framing.c
+++ b/src/framing.c
@@ -20,6 +20,10 @@
 
  ********************************************************************/
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #include <stdlib.h>
 #include <limits.h>
 #include <string.h>
@@ -723,8 +727,10 @@ long ogg_sync_pageseek(ogg_sync_state *oy,ogg_page *og){
       /* replace the computed checksum with the one actually read in */
       memcpy(page+22,chksum,4);
 
+#ifndef DISABLE_CRC
       /* Bad checksum. Lose sync */
       goto sync_fail;
+#endif
     }
   }
 
@@ -1814,6 +1820,7 @@ int main(void){
     test_pack(packets,headret,0,0,0);
   }
 
+#ifndef DISABLE_CRC
   {
     /* test for the libogg 1.1.1 resync in large continuation bug
        found by Josh Coalson)  */
@@ -1823,6 +1830,9 @@ int main(void){
     fprintf(stderr,"testing continuation resync in very large packets... ");
     test_pack(packets,headret,100,2,3);
   }
+#else
+    fprintf(stderr,"Skipping continuation resync test due to --disable-crc\n");
+#endif
 
   {
     /* term only page.  why not? */
@@ -2084,6 +2094,7 @@ int main(void){
       fprintf(stderr,"ok.\n");
     }
 
+#ifndef DISABLE_CRC
     /* Test recapture: page + garbage + page */
     {
       ogg_page og_de;
@@ -2125,6 +2136,9 @@ int main(void){
 
       fprintf(stderr,"ok.\n");
     }
+#else
+    fprintf(stderr,"Skipping recapture test due to --disable-crc\n");
+#endif
 
     /* Free page data that was previously copied */
     {