From: Francois-Xavier Le Bail <devel.fx.lebail@orange.fr>
Date: Fri, 8 Jan 2021 15:09:41 +0000 (+0100)
Subject: Add a nd_printjn() function
X-Git-Tag: tcpdump-4.99.5~189
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/432c2490b4e9253184909b4055d4fb381b2382b1

Add a nd_printjn() function

It prints a counted filename (or other ASCII string), part of
the packet buffer, filtering out non-printable characters.
Stop if truncated (via GET_U_1/longjmp) or after n bytes,
whichever is first.
The suffix comes from: j:longJmp, n:after N bytes.

(cherry picked from commit 90ddb17d272bbe39dccc08f7b109077b73996fee)
---

diff --git a/netdissect.h b/netdissect.h
index 9dc70db0..675af511 100644
--- a/netdissect.h
+++ b/netdissect.h
@@ -443,6 +443,7 @@ extern void fn_print_char(netdissect_options *, u_char);
 extern void fn_print_str(netdissect_options *, const u_char *);
 extern u_int nd_printztn(netdissect_options *, const u_char *, u_int, const u_char *);
 extern int nd_printn(netdissect_options *, const u_char *, u_int, const u_char *);
+extern void nd_printjn(netdissect_options *, const u_char *, u_int);
 extern void nd_printjnp(netdissect_options *, const u_char *, u_int);
 
 /*
diff --git a/util-print.c b/util-print.c
index 05483378..2408c8f4 100644
--- a/util-print.c
+++ b/util-print.c
@@ -171,6 +171,23 @@ nd_printn(netdissect_options *ndo,
 	return (n == 0) ? 0 : 1;
 }
 
+/*
+ * Print a counted filename (or other ASCII string), part of
+ * the packet buffer, filtering out non-printable characters.
+ * Stop if truncated (via GET_U_1/longjmp) or after n bytes,
+ * whichever is first.
+ * The suffix comes from: j:longJmp, n:after N bytes.
+ */
+void
+nd_printjn(netdissect_options *ndo, const u_char *s, u_int n)
+{
+	while (n > 0) {
+		fn_print_char(ndo, GET_U_1(s));
+		n--;
+		s++;
+	}
+}
+
 /*
  * Print a null-padded filename (or other ASCII string), part of
  * the packet buffer, filtering out non-printable characters.