git: c268c80fc3d5 - main - libsysdecode: cache Generic Netlink family IDs

The branch main has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=c268c80fc3d5eaeec2d01205b338dbaa7661502a

commit c268c80fc3d5eaeec2d01205b338dbaa7661502a
Author:     Ishan Agrawal <iagrawal9990@gmail.com>
AuthorDate: 2026-06-29 06:00:40 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2026-07-05 14:03:52 +0000

    libsysdecode: cache Generic Netlink family IDs
    
    Record Generic Netlink family IDs learned from
    CTRL_CMD_GETFAMILY responses and use them to decode subsequent
    Generic Netlink messages using symbolic family names instead of
    numeric IDs.
    
    Signed-off-by:  Ishan Agrawal <iagrawal9990@gmail.com>
    Reviewed by:    kp
    Sponsored-by:   Google LLC (GSoC 2026)
---
 lib/libsysdecode/netlink.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/lib/libsysdecode/netlink.c b/lib/libsysdecode/netlink.c
index 4dbe6c087dcf..a9c226e6065d 100644
--- a/lib/libsysdecode/netlink.c
+++ b/lib/libsysdecode/netlink.c
@@ -12,8 +12,11 @@
 #include <stdio.h>
 #include <stdbool.h>
 #include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include "sysdecode.h"
+#include "support.h"
 
 /*
  * Decodes a buffer as a Netlink message stream.
@@ -23,6 +26,9 @@
  * to fallback to a standard hex/string dump.
  */
 
+static struct name_table *family_table = NULL;
+static size_t num_family = 0;
+
 bool
 sysdecode_netlink(FILE *fp, const void *buf, size_t len, int protocol)
 {
@@ -41,6 +47,12 @@ sysdecode_netlink(FILE *fp, const void *buf, size_t len, int protocol)
 	if (nl->nlmsg_len < sizeof(struct nlmsghdr) || nl->nlmsg_len > remaining)
 		return (false);
 
+	if (family_table == NULL) {
+		family_table = malloc((num_family + 1) *
+		    sizeof(struct name_table));
+		family_table[num_family] = (struct name_table){0, NULL};
+	}
+
 	fprintf(fp, "netlink{");
 
 	while (remaining >= sizeof(struct nlmsghdr)) {
@@ -124,6 +136,22 @@ sysdecode_netlink(FILE *fp, const void *buf, size_t len, int protocol)
 				}
 			}
 
+			if (family_name && family_id &&
+			    !lookup_value(family_table, family_id)) {
+				num_family++;
+
+				family_table = realloc(family_table,
+				    (num_family + 1) *
+				    sizeof(struct name_table));
+				family_table[num_family - 1].val =
+				    family_id;
+				family_table[num_family - 1].str =
+				    strdup(family_name);
+
+				family_table[num_family] =
+				    (struct name_table){0, NULL};
+			}
+
 			fprintf(fp, "}");
 			break;
 		default:
@@ -131,6 +159,10 @@ sysdecode_netlink(FILE *fp, const void *buf, size_t len, int protocol)
 			break;
 		}
 
+		const char *family = lookup_value(family_table, nl->nlmsg_type);
+		if (family != NULL && strcmp(family, "pfctl") == 0)
+			fprintf(fp, ",pf={}");
+
 		/* Handle Alignment (Netlink messages are 4-byte aligned). */
 		size_t aligned_len = NLMSG_ALIGN(nl->nlmsg_len);
 		if (aligned_len > remaining)