trafgen: proto: Move proto headers into packet

Until now headers were used only for packet creation at compile time,
which does not allow to handle dynamic field updates at runtime. To
support dynamic updates, it is necessary to keep the proto_hdr entries
around after packet compilation so we can reference the header fields to
dynamically update.

Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
[tk: Adjust patch description, simplify code]
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

3 files changed, 28 insertions, 24 deletions

diff --git a/trafgen_conf.h b/trafgen_conf.h
index efce29c..934f8fe 100644
--- a/trafgen_conf.h
+++ b/trafgen_conf.h
@@ -5,6 +5,10 @@
 #include <stdio.h>
 #include <sys/types.h>
 
+#include "trafgen_proto.h"
+
+#define PROTO_MAX_LAYERS	16
+
 #define TYPE_INC	0
 #define TYPE_DEC	1
 
@@ -34,6 +38,8 @@ struct csum16 {
 struct packet {
 	uint8_t *payload;
 	size_t len;
+	struct proto_hdr *headers[PROTO_MAX_LAYERS];
+	size_t headers_count;
 };
 
 struct packet_dyn {
diff --git a/trafgen_parser.y b/trafgen_parser.y
index a286e6b..035d9c1 100644
--- a/trafgen_parser.y
+++ b/trafgen_parser.y
@@ -1004,11 +1004,21 @@ static void dump_conf(void)
 
 void cleanup_packets(void)
 {
-	size_t i;
+	size_t i, j;
 
 	for (i = 0; i < plen; ++i) {
-		if (packets[i].len > 0)
-			xfree(packets[i].payload);
+		struct packet *pkt = &packets[i];
+
+		if (pkt->len > 0)
+			xfree(pkt->payload);
+
+		for (j = 0; j < pkt->headers_count; j++) {
+			struct proto_hdr *hdr = pkt->headers[j];
+
+			if (hdr->fields)
+				xfree(hdr->fields);
+			xfree(hdr);
+		}
 	}
 
 	free(packets);
diff --git a/trafgen_proto.c b/trafgen_proto.c
index e5b1ad3..e08c9c2 100644
--- a/trafgen_proto.c
+++ b/trafgen_proto.c
@@ -24,15 +24,12 @@
 
 static struct proto_ctx ctx;
 
-#define PROTO_MAX_LAYERS	16
-
-static struct proto_hdr *headers[PROTO_MAX_LAYERS];
-static size_t headers_count;
-
 static struct proto_hdr *registered;
 
 struct proto_hdr *proto_lower_header(struct proto_hdr *hdr)
 {
+	struct proto_hdr **headers = current_packet()->headers;
+	size_t headers_count = current_packet()->headers_count;
 	struct proto_hdr *lower = NULL;
 	size_t i;
 
@@ -128,10 +125,11 @@ bool proto_field_is_set(struct proto_hdr *hdr, uint32_t fid)
 
 struct proto_hdr *proto_header_init(enum proto_id pid)
 {
+	struct proto_hdr **headers = current_packet()->headers;
 	struct proto_hdr *hdr = proto_header_by_id(pid);
 	struct proto_hdr *new_hdr;
 
-	bug_on(headers_count >= PROTO_MAX_LAYERS);
+	bug_on(current_packet()->headers_count >= PROTO_MAX_LAYERS);
 
 	new_hdr = xmalloc(sizeof(*new_hdr));
 	memcpy(new_hdr, hdr, sizeof(*new_hdr));
@@ -141,7 +139,7 @@ struct proto_hdr *proto_header_init(enum proto_id pid)
 	if (new_hdr->header_init)
 		new_hdr->header_init(new_hdr);
 
-	headers[headers_count++] = new_hdr;
+	headers[current_packet()->headers_count++] = new_hdr;
 	return new_hdr;
 }
 
@@ -155,9 +153,10 @@ struct proto_hdr *proto_lower_default_add(struct proto_hdr *hdr,
 					  enum proto_id pid)
 {
 	struct proto_hdr *current;
+	size_t headers_count = current_packet()->headers_count;
 
 	if (headers_count > 0) {
-		current = headers[headers_count - 1];
+		current = current_packet()->headers[headers_count - 1];
 
 		if (current->layer >= proto_header_by_id(pid)->layer)
 			goto set_proto;
@@ -418,6 +417,8 @@ void protos_init(const char *dev)
 
 void proto_packet_finish(void)
 {
+	struct proto_hdr **headers = current_packet()->headers;
+	size_t headers_count = current_packet()->headers_count;
 	ssize_t i;
 
 	/* Go down from upper layers to do last calculations (checksum) */
@@ -427,17 +428,4 @@ void proto_packet_finish(void)
 		if (p->packet_finish)
 			p->packet_finish(p);
 	}
-
-	for (i = 0; i < headers_count; i++) {
-		struct proto_hdr *p = headers[i];
-
-		if (p->fields) {
-			xfree(p->fields);
-			p->fields_count = 0;
-		}
-
-		xfree(headers[i]);
-	}
-
-	headers_count = 0;
 }