Merge pull request #18394 from donaldsharp/fpm_listener_output

zebra: add ability to specify output file with fpm_listener

1 files changed, 36 insertions, 25 deletions

diff --git a/zebra/fpm_listener.c b/zebra/fpm_listener.c
index 140cfa77cf..43ca6e47b8 100644
--- a/zebra/fpm_listener.c
+++ b/zebra/fpm_listener.c
@@ -44,6 +44,7 @@ struct glob {
 	int sock;
 	bool reflect;
 	bool dump_hex;
+	FILE *output_file;
 };
 
 struct glob glob_space;
@@ -123,13 +124,13 @@ static int accept_conn(int listen_sock)
 	while (1) {
 		char buf[120];
 
-		fprintf(stdout, "Waiting for client connection...\n");
+		fprintf(glob->output_file, "Waiting for client connection...\n");
 		client_len = sizeof(client_addr);
 		sock = accept(listen_sock, (struct sockaddr *)&client_addr,
 			      &client_len);
 
 		if (sock >= 0) {
-			fprintf(stdout, "Accepted client %s\n",
+			fprintf(glob->output_file, "Accepted client %s\n",
 				inet_ntop(AF_INET, &client_addr.sin_addr, buf, sizeof(buf)));
 			return sock;
 		}
@@ -172,8 +173,7 @@ read_fpm_msg(char *buf, size_t buf_len)
 		bytes_read = read(glob->sock, cur, need_len);
 
 		if (bytes_read == 0) {
-			fprintf(stdout,
-				"Socket closed as that read returned 0\n");
+			fprintf(glob->output_file, "Socket closed as that read returned 0\n");
 			return NULL;
 		}
 
@@ -567,7 +567,7 @@ addr_to_s(unsigned char family, void *addr)
 }
 
 /*
- * netlink_msg_ctx_print
+ * netlink_msg_ctx_snprint
  */
 static int netlink_msg_ctx_snprint(struct netlink_msg_ctx *ctx, char *buf,
 				   size_t buf_len)
@@ -628,7 +628,7 @@ static void print_netlink_msg_ctx(struct netlink_msg_ctx *ctx)
 	char buf[1024];
 
 	netlink_msg_ctx_snprint(ctx, buf, sizeof(buf));
-	printf("%s\n", buf);
+	fprintf(glob->output_file, "%s\n", buf);
 }
 
 static void fpm_listener_hexdump(const void *mem, size_t len)
@@ -641,7 +641,7 @@ static void fpm_listener_hexdump(const void *mem, size_t len)
 		return;
 
 	if (len == 0) {
-		printf("%016lx: (zero length / no data)\n", (long)src);
+		fprintf(glob->output_file, "%016lx: (zero length / no data)\n", (long)src);
 		return;
 	}
 
@@ -654,14 +654,14 @@ static void fpm_listener_hexdump(const void *mem, size_t len)
 		const uint8_t *lineend = src + 8;
 		uint32_t line_bytes = 0;
 
-		printf("%016lx: ", (long)src);
+		fprintf(glob->output_file, "%016lx: ", (long)src);
 
 		while (src < lineend && src < end) {
-			printf("%02x ", *src++);
+			fprintf(glob->output_file, "%02x ", *src++);
 			line_bytes++;
 		}
 		if (line_bytes < 8)
-			printf("%*s", (8 - line_bytes) * 3, "");
+			fprintf(glob->output_file, "%*s", (8 - line_bytes) * 3, "");
 
 		src -= line_bytes;
 		while (src < lineend && src < end && fb.pos < fb.buf + fb.len) {
@@ -672,7 +672,7 @@ static void fpm_listener_hexdump(const void *mem, size_t len)
 			else
 				*fb.pos++ = '.';
 		}
-		printf("\n");
+		fprintf(glob->output_file, "\n");
 	}
 }
 
@@ -711,20 +711,17 @@ static void parse_netlink_msg(char *buf, size_t buf_len, fpm_msg_hdr_t *fpm)
 
 			if (glob->reflect && hdr->nlmsg_type == RTM_NEWROUTE &&
 			    ctx->rtmsg->rtm_protocol > RTPROT_STATIC) {
-				printf("  Route %s(%u) reflecting back\n",
-				       netlink_prot_to_s(
-					       ctx->rtmsg->rtm_protocol),
-				       ctx->rtmsg->rtm_protocol);
+				fprintf(glob->output_file, "  Route %s(%u) reflecting back\n",
+					netlink_prot_to_s(ctx->rtmsg->rtm_protocol),
+					ctx->rtmsg->rtm_protocol);
 				ctx->rtmsg->rtm_flags |= RTM_F_OFFLOAD;
 				write(glob->sock, fpm, fpm_msg_len(fpm));
 			}
 			break;
 
 		default:
-			fprintf(stdout,
-				"Ignoring netlink message - Type: %s(%d)\n",
-				netlink_msg_type_to_s(hdr->nlmsg_type),
-				hdr->nlmsg_type);
+			fprintf(glob->output_file, "Ignoring netlink message - Type: %s(%d)\n",
+				netlink_msg_type_to_s(hdr->nlmsg_type), hdr->nlmsg_type);
 		}
 	}
 }
@@ -734,8 +731,8 @@ static void parse_netlink_msg(char *buf, size_t buf_len, fpm_msg_hdr_t *fpm)
  */
 static void process_fpm_msg(fpm_msg_hdr_t *hdr)
 {
-	fprintf(stdout, "FPM message - Type: %d, Length %d\n", hdr->msg_type,
-	      ntohs(hdr->msg_len));
+	fprintf(glob->output_file, "FPM message - Type: %d, Length %d\n", hdr->msg_type,
+		ntohs(hdr->msg_len));
 
 	if (hdr->msg_type != FPM_MSG_TYPE_NETLINK) {
 		fprintf(stderr, "Unknown fpm message type %u\n", hdr->msg_type);
@@ -770,12 +767,12 @@ int main(int argc, char **argv)
 	pid_t daemon;
 	int r;
 	bool fork_daemon = false;
-
-	setbuf(stdout, NULL);
+	const char *output_file = NULL;
 
 	memset(glob, 0, sizeof(*glob));
+	glob->output_file = stdout;
 
-	while ((r = getopt(argc, argv, "rdv")) != -1) {
+	while ((r = getopt(argc, argv, "rdvo:")) != -1) {
 		switch (r) {
 		case 'r':
 			glob->reflect = true;
@@ -786,9 +783,23 @@ int main(int argc, char **argv)
 		case 'v':
 			glob->dump_hex = true;
 			break;
+		case 'o':
+			output_file = optarg;
+			break;
 		}
 	}
 
+	if (output_file) {
+		glob->output_file = fopen(output_file, "w");
+		if (!glob->output_file) {
+			fprintf(stderr, "Failed to open output file %s: %s\n", output_file,
+				strerror(errno));
+			exit(1);
+		}
+	}
+
+	setbuf(glob->output_file, NULL);
+
 	if (fork_daemon) {
 		daemon = fork();
 
@@ -805,7 +816,7 @@ int main(int argc, char **argv)
 	while (1) {
 		glob->sock = accept_conn(glob->server_sock);
 		fpm_serve();
-		fprintf(stdout, "Done serving client");
+		fprintf(glob->output_file, "Done serving client\n");
 	}
 }
 #else