PR: bin/9016

    Fix bug with od/hd/hexdump. "*" lines are supposed to indicate one or
    duplicates of the previous line, but a small file with less then 16
    characters of zeros in it will be falsy identified as a repeat of
    the (non-existant) previous line.  i.e. the first line of output winds
    up being a "*".  Added a bit of code to handle the degenerate 'there is
    no previous line' case for the first line.

1 files changed, 8 insertions, 3 deletions

diff --git a/usr.bin/hexdump/display.c b/usr.bin/hexdump/display.c
index 0a74542..b72da84 100644
--- a/usr.bin/hexdump/display.c
+++ b/usr.bin/hexdump/display.c
@@ -36,7 +36,7 @@
 static char sccsid[] = "@(#)display.c	8.1 (Berkeley) 6/6/93";
 #endif
 static const char rcsid[] =
-	"$Id$";
+	"$Id: display.c,v 1.2 1997/07/10 06:48:12 charnier Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -234,6 +234,7 @@ get()
 	static u_char *curp, *savp;
 	register int n;
 	int need, nread;
+	int valid_save = 0;
 	u_char *tmpp;
 
 	if (!curp) {
@@ -244,6 +245,7 @@ get()
 		curp = savp;
 		savp = tmpp;
 		address += blocksize;
+		valid_save = 1;
 	}
 	for (need = blocksize, nread = 0;;) {
 		/*
@@ -254,7 +256,9 @@ get()
 		if (!length || ateof && !next((char **)NULL)) {
 			if (need == blocksize)
 				return((u_char *)NULL);
-			if (vflag != ALL && !bcmp(curp, savp, nread)) {
+			if (vflag != ALL && 
+			    valid_save && 
+			    bcmp(curp, savp, nread) == 0) {
 				if (vflag != DUP)
 					(void)printf("*\n");
 				return((u_char *)NULL);
@@ -276,7 +280,8 @@ get()
 			length -= n;
 		if (!(need -= n)) {
 			if (vflag == ALL || vflag == FIRST ||
-			    bcmp(curp, savp, blocksize)) {
+			    valid_save == 0 ||
+			    bcmp(curp, savp, blocksize) != 0) {
 				if (vflag == DUP || vflag == FIRST)
 					vflag = WAIT;
 				return(curp);