From 6f09031e4d04727cc72164fefcbc763e37556493 Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Mon, 15 Jan 2024 13:02:16 +0900
Subject: [PATCH] network/route: introduce reverse map for route with nexthop
 ID

It is not used in this commit, but will be used later.
Preparation for later commits.

This is the one for routes of 531c7246829a41dd7e51847bd4d77aa012ff478f.
---
 src/network/networkd-nexthop.c       |  1 +
 src/network/networkd-nexthop.h       |  3 +-
 src/network/networkd-route-nexthop.c | 43 ++++++++++++++++++++++++++++
 src/network/networkd-route-nexthop.h |  3 ++
 src/network/networkd-route.c         |  8 ++++++
 src/network/networkd-route.h         |  1 +
 6 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/src/network/networkd-nexthop.c b/src/network/networkd-nexthop.c
index cf62e0e82d..67eba509d3 100644
--- a/src/network/networkd-nexthop.c
+++ b/src/network/networkd-nexthop.c
@@ -97,6 +97,7 @@ static NextHop* nexthop_free(NextHop *nexthop) {
         config_section_free(nexthop->section);
         hashmap_free_free(nexthop->group);
         set_free(nexthop->nexthops);
+        set_free(nexthop->routes);
 
         return mfree(nexthop);
 }
diff --git a/src/network/networkd-nexthop.h b/src/network/networkd-nexthop.h
index 74b23bd772..9ce36c6cd9 100644
--- a/src/network/networkd-nexthop.h
+++ b/src/network/networkd-nexthop.h
@@ -41,8 +41,9 @@ typedef struct NextHop {
         /* Only used in conf parser and nexthop_section_verify(). */
         int onlink;
 
-        /* For managing nexthops that depend on this nexthop. */
+        /* For managing routes and nexthops that depend on this nexthop. */
         Set *nexthops;
+        Set *routes;
 } NextHop;
 
 NextHop* nexthop_ref(NextHop *nexthop);
diff --git a/src/network/networkd-route-nexthop.c b/src/network/networkd-route-nexthop.c
index 8ccd4e66e8..f7a2201b6b 100644
--- a/src/network/networkd-route-nexthop.c
+++ b/src/network/networkd-route-nexthop.c
@@ -5,6 +5,7 @@
 #include "alloc-util.h"
 #include "extract-word.h"
 #include "netlink-util.h"
+#include "networkd-manager.h"
 #include "networkd-network.h"
 #include "networkd-nexthop.h"
 #include "networkd-route.h"
@@ -13,6 +14,48 @@
 #include "parse-util.h"
 #include "string-util.h"
 
+void route_detach_from_nexthop(Route *route) {
+        NextHop *nh;
+
+        assert(route);
+        assert(route->manager);
+
+        if (route->nexthop_id == 0)
+                return;
+
+        if (nexthop_get_by_id(route->manager, route->nexthop_id, &nh) < 0)
+                return;
+
+        route_unref(set_remove(nh->routes, route));
+}
+
+void route_attach_to_nexthop(Route *route) {
+        NextHop *nh;
+        int r;
+
+        assert(route);
+        assert(route->manager);
+
+        if (route->nexthop_id == 0)
+                return;
+
+        r = nexthop_get_by_id(route->manager, route->nexthop_id, &nh);
+        if (r < 0) {
+                if (route->manager->manage_foreign_nexthops)
+                        log_debug_errno(r, "Route has unknown nexthop ID (%"PRIu32"), ignoring.",
+                                        route->nexthop_id);
+                return;
+        }
+
+        r = set_ensure_put(&nh->routes, &route_hash_ops_unref, route);
+        if (r < 0)
+                return (void) log_debug_errno(r, "Failed to save route to nexthop, ignoring: %m");
+        if (r == 0)
+                return (void) log_debug("Duplicated route assigned to nexthop, ignoring.");
+
+        route_ref(route);
+}
+
 static void route_nexthop_done(RouteNextHop *nh) {
         assert(nh);
 
diff --git a/src/network/networkd-route-nexthop.h b/src/network/networkd-route-nexthop.h
index 5e4602d3cd..f9a147839d 100644
--- a/src/network/networkd-route-nexthop.h
+++ b/src/network/networkd-route-nexthop.h
@@ -26,6 +26,9 @@ typedef struct RouteNextHop {
 
 #define ROUTE_NEXTHOP_NULL ((const RouteNextHop) {})
 
+void route_detach_from_nexthop(Route *route);
+void route_attach_to_nexthop(Route *route);
+
 RouteNextHop* route_nexthop_free(RouteNextHop *nh);
 DEFINE_TRIVIAL_CLEANUP_FUNC(RouteNextHop*, route_nexthop_free);
 
diff --git a/src/network/networkd-route.c b/src/network/networkd-route.c
index 147d9cb14f..80e20a286b 100644
--- a/src/network/networkd-route.c
+++ b/src/network/networkd-route.c
@@ -33,6 +33,7 @@ static Route* route_detach_impl(Route *route) {
         }
 
         if (route->manager) {
+                route_detach_from_nexthop(route);
                 set_remove(route->manager->routes, route);
                 route->manager = NULL;
                 return route;
@@ -220,6 +221,13 @@ DEFINE_HASH_OPS_WITH_KEY_DESTRUCTOR(
                 route_compare_func,
                 route_detach);
 
+DEFINE_HASH_OPS_WITH_KEY_DESTRUCTOR(
+                route_hash_ops_unref,
+                Route,
+                route_hash_func,
+                route_compare_func,
+                route_unref);
+
 DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(
                 route_section_hash_ops,
                 ConfigSection,
diff --git a/src/network/networkd-route.h b/src/network/networkd-route.h
index 004295e599..c5c2693ac4 100644
--- a/src/network/networkd-route.h
+++ b/src/network/networkd-route.h
@@ -81,6 +81,7 @@ struct Route {
 };
 
 extern const struct hash_ops route_hash_ops;
+extern const struct hash_ops route_hash_ops_unref;
 
 Route* route_ref(Route *route);
 Route* route_unref(Route *route);