r25799: Add dump_data_skip_zeros() which omits 16 zero bytes in a row (if not at the

beginning or the end of a blob). Usefull when inspecting protocols that
exchange huge mostly empty blobs.

Guenther
(This used to be commit c96047d022555678dabe08c0de94f0913bb4d047)

2 files changed, 71 insertions, 9 deletions

diff --git a/source4/lib/util/util.c b/source4/lib/util/util.c
index 2a2813f9af..ac9ae779a0 100644
--- a/source4/lib/util/util.c
+++ b/source4/lib/util/util.c
@@ -393,24 +393,55 @@ static void print_asc(int level, const uint8_t *buf,int len)
  *
  * The data is only written if the log level is at least level.
  */
-_PUBLIC_ void dump_data(int level, const uint8_t *buf,int len)
+static void _dump_data(int level, const uint8_t *buf, int len,
+		       bool omit_zero_bytes)
 {
 	int i=0;
+	const uint8_t empty[16];
+	bool skipped = false;
+
 	if (len<=0) return;
 
 	if (!DEBUGLVL(level)) return;
-	
-	DEBUGADD(level,("[%03X] ",i));
+
+	memset(&empty, '\0', 16);
+
 	for (i=0;i<len;) {
+
+		if (i%16 == 0) {
+			if ((omit_zero_bytes == true) &&
+			    (i > 0) &&
+			    (len > i+16) &&
+			    (memcmp(&buf[i], &empty, 16) == 0))
+			{
+				i +=16;
+				continue;
+			}
+
+			if (i<len)  {
+				DEBUGADD(level,("[%04X] ",i));
+			}
+		}
+
 		DEBUGADD(level,("%02X ",(int)buf[i]));
 		i++;
-		if (i%8 == 0) DEBUGADD(level,(" "));
-		if (i%16 == 0) {      
+		if (i%8 == 0) DEBUGADD(level,("  "));
+		if (i%16 == 0) {
+
 			print_asc(level,&buf[i-16],8); DEBUGADD(level,(" "));
 			print_asc(level,&buf[i-8],8); DEBUGADD(level,("\n"));
-			if (i<len) DEBUGADD(level,("[%03X] ",i));
+
+			if ((omit_zero_bytes == true) &&
+			    (len > i+16) &&
+			    (memcmp(&buf[i], &empty, 16) == 0)) {
+				if (!skipped) {
+					DEBUGADD(level,("skipping zero buffer bytes\n"));
+					skipped = true;
+				}
+			}
 		}
 	}
+
 	if (i%16) {
 		int n;
 		n = 16 - (i%16);
@@ -420,12 +451,35 @@ _PUBLIC_ void dump_data(int level, const uint8_t *buf,int len)
 		n = MIN(8,i%16);
 		print_asc(level,&buf[i-(i%16)],n); DEBUGADD(level,( " " ));
 		n = (i%16) - n;
-		if (n>0) print_asc(level,&buf[i-n],n); 
-		DEBUGADD(level,("\n"));    
-	}	
+		if (n>0) print_asc(level,&buf[i-n],n);
+		DEBUGADD(level,("\n"));
+	}
+
 }
 
 /**
+ * Write dump of binary data to the log file.
+ *
+ * The data is only written if the log level is at least level.
+ */
+_PUBLIC_ void dump_data(int level, const uint8_t *buf, int len)
+{
+	return _dump_data(level, buf, len, false);
+}
+
+/**
+ * Write dump of binary data to the log file.
+ *
+ * The data is only written if the log level is at least level.
+ * 16 zero bytes in a row are ommited
+ */
+_PUBLIC_ void dump_data_skip_zeros(int level, const uint8_t *buf, int len)
+{
+	return _dump_data(level, buf, len, true);
+}
+
+
+/**
  malloc that aborts with smb_panic on fail or zero size.
 **/
 
diff --git a/source4/lib/util/util.h b/source4/lib/util/util.h
index fc9cb1e57a..f3adbb3333 100644
--- a/source4/lib/util/util.h
+++ b/source4/lib/util/util.h
@@ -656,6 +656,14 @@ _PUBLIC_ bool fcntl_lock(int fd, int op, off_t offset, off_t count, int type);
 _PUBLIC_ void dump_data(int level, const uint8_t *buf,int len);
 
 /**
+ * Write dump of binary data to the log file.
+ *
+ * The data is only written if the log level is at least level.
+ * 16 zero bytes in a row are ommited
+ */
+_PUBLIC_ void dump_data_skip_zeros(int level, const uint8_t *buf, int len);
+
+/**
  malloc that aborts with smb_panic on fail or zero size.
 **/
 _PUBLIC_ void *smb_xmalloc(size_t size);