From: Francois-Xavier Le Bail <devel.fx.lebail@orange.fr>
Date: Fri, 18 Sep 2020 11:17:39 +0000 (+0200)
Subject: Use a switch to manage the setjmp() return values
X-Git-Tag: tcpdump-4.99-bp~223
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/a2a16f6b4c76ca6d5a9bce323ef22613d153ae9e

Use a switch to manage the setjmp() return values

Also rename 'ndo_truncated' to 'ndo_early_end'.

The current case (truncated packet) uses ND_TRUNCATED value.

Prepare to add other cases when the current packet cannot be processed
any more ('Invalid' cases, etc.).
---

diff --git a/extract.h b/extract.h
index dfb21f69..58b8cc19 100644
--- a/extract.h
+++ b/extract.h
@@ -578,7 +578,7 @@ EXTRACT_IPV4_TO_NETWORK_ORDER(const void *p)
 static inline NORETURN void
 nd_trunc(netdissect_options *ndo)
 {
-	longjmp(ndo->ndo_truncated, 1);
+	longjmp(ndo->ndo_early_end, ND_TRUNCATED);
 }
 
 /* get_u_1 and get_s_1 */
diff --git a/netdissect.h b/netdissect.h
index b774ae63..e430a0b8 100644
--- a/netdissect.h
+++ b/netdissect.h
@@ -194,6 +194,9 @@ struct netdissect_saved_packet_info {
   struct netdissect_saved_packet_info *ndspi_prev;	/* previous buffer on the stack */
 };
 
+/* 'val' value(s) for longjmp */
+#define ND_TRUNCATED 1
+
 struct netdissect_options {
   int ndo_bflag;		/* print 4 byte ASes in ASDOT notation */
   int ndo_eflag;		/* print ethernet header */
@@ -213,7 +216,7 @@ struct netdissect_options {
 				 */
   int ndo_Hflag;		/* dissect 802.11s draft mesh standard */
   const char *ndo_protocol;	/* protocol */
-  jmp_buf ndo_truncated;	/* jmp_buf for setjmp()/longjmp() */
+  jmp_buf ndo_early_end;	/* jmp_buf for setjmp()/longjmp() */
   void *ndo_last_mem_p;		/* pointer to the last allocated memory chunk */
   int ndo_packet_number;	/* print a packet number in the beginning of line */
   int ndo_suppress_default_print; /* don't use default_print() for unknown packet types */
diff --git a/print.c b/print.c
index 6e4cf893..864e9ddd 100644
--- a/print.c
+++ b/print.c
@@ -398,12 +398,15 @@ pretty_print_packet(netdissect_options *ndo, const struct pcap_pkthdr *h,
 
 	ndo->ndo_protocol = "";
 	ndo->ndo_ll_hdr_len = 0;
-	if (setjmp(ndo->ndo_truncated) == 0) {
+	switch (setjmp(ndo->ndo_early_end)) {
+	case 0:
 		/* Print the packet. */
 		(ndo->ndo_if_printer)(ndo, h, sp);
-	} else {
+		break;
+	case ND_TRUNCATED:
 		/* A printer quit because the packet was truncated; report it */
 		nd_print_trunc(ndo);
+		break;
 	}
 	hdrlen = ndo->ndo_ll_hdr_len;