+/* Copyright (c) 2006-2014. The SimGrid Team.
+ * All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "xbt/log.h"
+
+#include "simgrid/s4u/As.hpp"
+#include "src/surf/AsImpl.hpp"
+#include "src/surf/network_interface.hpp" // Link FIXME: move to proper header
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(AsImpl,surf, "Implementation of S4U autonomous systems");
+
+namespace simgrid {
+ namespace surf {
+
+ AsImpl::AsImpl(const char *name)
+ : As(name)
+ {
+ }
+ AsImpl::~AsImpl()
+ {
+ xbt_dynar_free(&upDownLinks);
+ delete netcard_;
+ }
+
+ xbt_dynar_t AsImpl::getOneLinkRoutes() {
+ return NULL;
+ }
+
+ /** @brief Get the common ancestor and its first childs in each line leading to src and dst */
+ static void find_common_ancestors(NetCard *src, NetCard *dst,
+ /* OUT */ AsImpl **common_ancestor, AsImpl **src_ancestor, AsImpl **dst_ancestor)
+ {
+ #define ROUTING_HIERARCHY_MAXDEPTH 32 /* increase if it is not enough */
+ AsImpl *path_src[ROUTING_HIERARCHY_MAXDEPTH];
+ AsImpl *path_dst[ROUTING_HIERARCHY_MAXDEPTH];
+ int index_src = 0;
+ int index_dst = 0;
+ AsImpl *current_src;
+ AsImpl *current_dst;
+ AsImpl *father;
+
+ /* (1) find the path to root of src and dst*/
+ AsImpl *src_as = src->containingAS();
+ AsImpl *dst_as = dst->containingAS();
+
+ xbt_assert(src_as, "Host %s must be in an AS", src->name());
+ xbt_assert(dst_as, "Host %s must be in an AS", dst->name());
+
+ /* (2) find the path to the root routing component */
+ for (AsImpl *current = src_as; current != NULL; current = static_cast<AsImpl*>(current->father())) {
+ xbt_assert(index_src < ROUTING_HIERARCHY_MAXDEPTH, "ROUTING_HIERARCHY_MAXDEPTH should be increased for element %s", src->name());
+ path_src[index_src++] = current;
+ }
+ for (AsImpl *current = dst_as; current != NULL; current = static_cast<AsImpl*>(current->father())) {
+ xbt_assert(index_dst < ROUTING_HIERARCHY_MAXDEPTH,"ROUTING_HIERARCHY_MAXDEPTH should be increased for path_dst");
+ path_dst[index_dst++] = current;
+ }
+
+ /* (3) find the common father.
+ * Before that, index_src and index_dst may be different, they both point to NULL in path_src/path_dst
+ * So we move them down simultaneously as long as they point to the same content.
+ */
+ do {
+ current_src = path_src[--index_src];
+ current_dst = path_dst[--index_dst];
+ } while (index_src > 0 && index_dst > 0 && current_src == current_dst);
+
+ /* (4) if we did not find a difference (index_src or index_dst went to 0), both elements are in the same AS */
+ if (current_src == current_dst)
+ father = current_src;
+ else // we found a difference
+ father = path_src[index_src + 1];
+
+ /* (5) result generation */
+ *common_ancestor = father; /* the common father of src and dst */
+ *src_ancestor = current_src; /* the first different father of src */
+ *dst_ancestor = current_dst; /* the first different father of dst */
+ #undef ROUTING_HIERARCHY_MAXDEPTH
+ }
+
+
+ /* PRECONDITION: this is the common ancestor of src and dst */
+ std::vector<surf::Link*> *AsImpl::getBypassRoute(surf::NetCard *src, surf::NetCard *dst)
+ {
+ // If never set a bypass route return NULL without any further computations
+ XBT_DEBUG("generic_get_bypassroute from %s to %s", src->name(), dst->name());
+ if (bypassRoutes_.empty())
+ return nullptr;
+
+ std::vector<surf::Link*> *bypassedRoute = nullptr;
+
+ if(dst->containingAS() == this && src->containingAS() == this ){
+ if (bypassRoutes_.find({src->name(),dst->name()}) != bypassRoutes_.end()) {
+ bypassedRoute = bypassRoutes_.at({src->name(),dst->name()});
+ XBT_DEBUG("Found a bypass route with %zu links",bypassedRoute->size());
+ }
+ return bypassedRoute;
+ }
+
+ /* (2) find the path to the root routing component */
+ std::vector<As*> path_src;
+ As *current = src->containingAS();
+ while (current != NULL) {
+ path_src.push_back(current);
+ current = current->father_;
+ }
+
+ std::vector<As*> path_dst;
+ current = dst->containingAS();
+ while (current != NULL) {
+ path_dst.push_back(current);
+ current = current->father_;
+ }
+
+ /* (3) find the common father */
+ while (path_src.size() > 1 && path_dst.size() >1
+ && path_src.at(path_src.size() -1) == path_dst.at(path_dst.size() -1)) {
+ path_src.pop_back();
+ path_dst.pop_back();
+ }
+
+ int max_index_src = path_src.size() - 1;
+ int max_index_dst = path_dst.size() - 1;
+
+ int max_index = std::max(max_index_src, max_index_dst);
+
+ for (int max = 0; max <= max_index; max++) {
+ for (int i = 0; i < max; i++) {
+ if (i <= max_index_src && max <= max_index_dst) {
+ const std::pair<std::string, std::string> key = {path_src.at(i)->name(), path_dst.at(max)->name()};
+ if (bypassRoutes_.find(key) != bypassRoutes_.end())
+ bypassedRoute = bypassRoutes_.at(key);
+ }
+ if (bypassedRoute)
+ break;
+ if (max <= max_index_src && i <= max_index_dst) {
+ const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(i)->name()};
+ if (bypassRoutes_.find(key) != bypassRoutes_.end())
+ bypassedRoute = bypassRoutes_.at(key);
+ }
+ if (bypassedRoute)
+ break;
+ }
+
+ if (bypassedRoute)
+ break;
+
+ if (max <= max_index_src && max <= max_index_dst) {
+ const std::pair<std::string, std::string> key = {path_src.at(max)->name(), path_dst.at(max)->name()};
+ if (bypassRoutes_.find(key) != bypassRoutes_.end())
+ bypassedRoute = bypassRoutes_.at(key);
+ }
+ if (bypassedRoute)
+ break;
+ }
+
+ return bypassedRoute;
+ }
+
+ /**
+ * \brief Recursive function for getRouteAndLatency
+ *
+ * \param src the source host
+ * \param dst the destination host
+ * \param links Where to store the links and the gw information
+ * \param latency If not NULL, the latency of all links will be added in it
+ */
+ void AsImpl::getRouteRecursive(surf::NetCard *src, surf::NetCard *dst,
+ /* OUT */ std::vector<surf::Link*> * links, double *latency)
+ {
+ s_sg_platf_route_cbarg_t route;
+ memset(&route,0,sizeof(route));
+
+ XBT_DEBUG("Solve route/latency \"%s\" to \"%s\"", src->name(), dst->name());
+
+ /* Find how src and dst are interconnected */
+ AsImpl *common_ancestor, *src_ancestor, *dst_ancestor;
+ find_common_ancestors(src, dst, &common_ancestor, &src_ancestor, &dst_ancestor);
+ XBT_DEBUG("elements_father: common ancestor '%s' src ancestor '%s' dst ancestor '%s'",
+ common_ancestor->name(), src_ancestor->name(), dst_ancestor->name());
+
+ /* Check whether a direct bypass is defined. If so, use it and bail out */
+ std::vector<surf::Link*> *bypassed_route = common_ancestor->getBypassRoute(src, dst);
+ if (nullptr != bypassed_route) {
+ for (surf::Link *link : *bypassed_route) {
+ links->push_back(link);
+ if (latency)
+ *latency += link->getLatency();
+ }
+ return;
+ }
+
+ /* If src and dst are in the same AS, life is good */
+ if (src_ancestor == dst_ancestor) { /* SURF_ROUTING_BASE */
+ route.link_list = links;
+ common_ancestor->getRouteAndLatency(src, dst, &route, latency);
+ return;
+ }
+
+ /* Not in the same AS, no bypass. We'll have to find our path between the ASes recursively*/
+
+ route.link_list = new std::vector<surf::Link*>();
+
+ common_ancestor->getRouteAndLatency(src_ancestor->netcard_, dst_ancestor->netcard_, &route, latency);
+ xbt_assert((route.gw_src != NULL) && (route.gw_dst != NULL),
+ "bad gateways for route from \"%s\" to \"%s\"", src->name(), dst->name());
+
+ /* If source gateway is not our source, we have to recursively find our way up to this point */
+ if (src != route.gw_src)
+ getRouteRecursive(src, route.gw_src, links, latency);
+ for (auto link: *route.link_list)
+ links->push_back(link);
+
+ /* If dest gateway is not our destination, we have to recursively find our way from this point */
+ if (route.gw_dst != dst)
+ getRouteRecursive(route.gw_dst, dst, links, latency);
+
+ }
+
+ }
+};