From 5a925d5f91e32245446ba568da2549b08913c0c7 Mon Sep 17 00:00:00 2001
From: Michael Tremer <michael.tremer@ipfire.org>
Date: Fri, 9 Jun 2023 05:28:51 +0000
Subject: [PATCH] networkd: Open config directory and keep a handle to it

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---
 src/networkd/config.c |  2 +-
 src/networkd/config.h |  1 +
 src/networkd/daemon.c | 71 ++++++++++++++++++++++++++++++++++++++-----
 3 files changed, 66 insertions(+), 8 deletions(-)

diff --git a/src/networkd/config.c b/src/networkd/config.c
index ee5e8b83..b7f3f722 100644
--- a/src/networkd/config.c
+++ b/src/networkd/config.c
@@ -229,7 +229,7 @@ int nw_config_flush(nw_config* config) {
 	return 0;
 }
 
-static int nw_config_readf(nw_config* config, FILE* f) {
+int nw_config_readf(nw_config* config, FILE* f) {
 	char* line = NULL;
 	size_t length = 0;
 	int r;
diff --git a/src/networkd/config.h b/src/networkd/config.h
index 63e9d180..d532da33 100644
--- a/src/networkd/config.h
+++ b/src/networkd/config.h
@@ -40,6 +40,7 @@ const char* nw_config_path(nw_config* config);
 
 int nw_config_flush(nw_config* config);
 
+int nw_config_readf(nw_config* config, FILE* f);
 int nw_config_read(nw_config* config);
 int nw_config_write(nw_config* config);
 
diff --git a/src/networkd/daemon.c b/src/networkd/daemon.c
index 31fda8ec..e645beec 100644
--- a/src/networkd/daemon.c
+++ b/src/networkd/daemon.c
@@ -18,7 +18,9 @@
 #                                                                             #
 #############################################################################*/
 
+#include <dirent.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <getopt.h>
 #include <limits.h>
 #include <stdlib.h>
@@ -48,7 +50,7 @@
 struct nw_daemon {
 	int nrefs;
 
-	char config_path[PATH_MAX];
+	DIR* config_dir;
 	nw_config* config;
 
 	// Event Loop
@@ -95,6 +97,43 @@ static int __nw_daemon_reload(sd_event_source* source, const struct signalfd_sig
 	return 0;
 }
 
+/*
+	Configuration
+*/
+
+static int nw_daemon_config_open(nw_daemon* daemon, const char* path) {
+	daemon->config_dir = opendir(path);
+	if (!daemon->config_dir) {
+		ERROR("Could not open %s: %m\n", path);
+		return -errno;
+	}
+
+	return 0;
+}
+
+static FILE* nw_daemon_config_fopen(nw_daemon* daemon, const char* path, const char* mode) {
+	int r;
+
+	// If no configuration path has been opened yet, we will open something
+	if (!daemon->config_dir) {
+		r = nw_daemon_config_open(daemon, CONFIG_DIR);
+		if (r < 0) {
+			errno = -r;
+			return NULL;
+		}
+	}
+
+	// Open the file
+	int fd = openat(dirfd(daemon->config_dir), path, 0);
+	if (fd < 0) {
+		ERROR("Could not open configuration file %s: %m\n", path);
+		return NULL;
+	}
+
+	// Return a file handle
+	return fdopen(fd, mode);
+}
+
 static int nw_daemon_parse_argv(nw_daemon* daemon, int argc, char* argv[]) {
 	enum {
 		ARG_CONFIG,
@@ -114,10 +153,9 @@ static int nw_daemon_parse_argv(nw_daemon* daemon, int argc, char* argv[]) {
 
 		switch (c) {
 			case ARG_CONFIG:
-				r = nw_string_set(daemon->config_path, optarg);
+				r = nw_daemon_config_open(daemon, optarg);
 				if (r < 0)
 					return r;
-
 				break;
 
 			// Abort on any unrecognised option
@@ -174,12 +212,29 @@ static int nw_daemon_setup_loop(nw_daemon* daemon) {
 }
 
 static int nw_daemon_load_config(nw_daemon* daemon) {
+	FILE* f = NULL;
 	int r;
 
-	// Read configuration file
-	r = nw_config_create(&daemon->config, CONFIG_DIR "/settings");
-	if (r)
-		return r;
+	// Open the configuration file
+	f = nw_daemon_config_fopen(daemon, "settings", "r");
+	if (!f) {
+		r = -errno;
+		goto ERROR;
+	}
+
+	// Create configuration
+	r = nw_config_create(&daemon->config, NULL);
+	if (r < 0)
+		goto ERROR;
+
+	// Parse configuration
+	r = nw_config_readf(daemon->config, f);
+	if (r < 0)
+		goto ERROR;
+
+ERROR:
+	if (f)
+		fclose(f);
 
 	return r;
 }
@@ -482,6 +537,8 @@ static void nw_daemon_free(nw_daemon* daemon) {
 	// Cleanup common objects
 	nw_daemon_cleanup(daemon);
 
+	if (daemon->config_dir)
+		closedir(daemon->config_dir);
 	if (daemon->stats_collector_event)
 		sd_event_source_unref(daemon->stats_collector_event);
 	if (daemon->bus)
-- 
2.39.2