From 5d89130fb9fcec18fc846a8df173fb4d67bcec48 Mon Sep 17 00:00:00 2001
From: Sam Hocevar <sam@hocevar.net>
Date: Wed, 3 Jan 2007 22:25:45 +0000
Subject: [PATCH]   * Do not fuzz anything if 0 bytes were read.   * Added a
 debug message for fuzzing.

---
 src/fuzz.c        | 4 +++-
 src/load-stream.c | 7 +++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/fuzz.c b/src/fuzz.c
index fe1d6a3..d981653 100644
--- a/src/fuzz.c
+++ b/src/fuzz.c
@@ -42,8 +42,10 @@ void _zz_fuzz(int fd, uint8_t *buf, uint64_t len)
     unsigned long int pos = _zz_getpos(fd);
     unsigned int i, j, todo;
 
-    fuzz = _zz_getfuzz(fd);
+    debug("fuzz(%i, %lli@%li)", fd, (unsigned long long int)len,
+          (unsigned long int)pos);
 
+    fuzz = _zz_getfuzz(fd);
     aligned_buf = buf - pos;
 
     for(i = pos / CHUNKBYTES;
diff --git a/src/load-stream.c b/src/load-stream.c
index 92aac09..6641c14 100644
--- a/src/load-stream.c
+++ b/src/load-stream.c
@@ -167,8 +167,11 @@ size_t fread(void *ptr, size_t size, size_t nmemb, FILE *stream)
         /* XXX: the number of bytes read is not ret * size, because
          * a partial read may have advanced the stream pointer */
         long int newpos = ftell(stream);
-        _zz_fuzz(fd, ptr, newpos - pos);
-        _zz_setpos(fd, newpos);
+        if(newpos != pos)
+        {
+            _zz_fuzz(fd, ptr, newpos - pos);
+            _zz_setpos(fd, newpos);
+        }
     }
     return ret;
 }