X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/e39d3a7637657a34fe154348228c07842430828d..9b14512ff2a75b435a9d0b8f8810b3a22ad3a309:/src/xbt/graph.c

diff --git a/src/xbt/graph.c b/src/xbt/graph.c
index ef852803cc..befa76cd7d 100644
--- a/src/xbt/graph.c
+++ b/src/xbt/graph.c
@@ -1,6 +1,6 @@
 /* a generic graph library.                                                 */
 
-/* Copyright (c) 2006-2014. The SimGrid Team.
+/* Copyright (c) 2006-2017. The SimGrid Team.
  * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
@@ -12,24 +12,20 @@
 #include "graph_private.h"
 #include "xbt/dict.h"
 #include "xbt/heap.h"
-#include "xbt/str.h"
 #include "xbt/file.h"
 
 #include <errno.h>
+#include <stdio.h>
 #include <stdlib.h>
 
-
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_graph, xbt, "Graph");
 
-
-
 /** @brief Constructor
  *  @return a new graph
  */
 xbt_graph_t xbt_graph_new_graph(unsigned short int directed, void *data)
 {
-  xbt_graph_t graph = NULL;
-  graph = xbt_new0(struct xbt_graph, 1);
+  xbt_graph_t graph = xbt_new0(struct xbt_graph, 1);
   graph->directed = directed;
   graph->data = data;
   graph->nodes = xbt_dynar_new(sizeof(xbt_node_t), NULL);
@@ -41,8 +37,7 @@ xbt_graph_t xbt_graph_new_graph(unsigned short int directed, void *data)
 /** @brief add a node to the given graph */
 xbt_node_t xbt_graph_new_node(xbt_graph_t g, void *data)
 {
-  xbt_node_t node = NULL;
-  node = xbt_new0(struct xbt_node, 1);
+  xbt_node_t node= xbt_new0(struct xbt_node, 1);
   node->data = data;
   if (g->directed)
     /* only the "out" field is used */
@@ -60,9 +55,7 @@ xbt_node_t xbt_graph_new_node(xbt_graph_t g, void *data)
 /** @brief add an edge to the given graph */
 xbt_edge_t xbt_graph_new_edge(xbt_graph_t g, xbt_node_t src, xbt_node_t dst, void *data)
 {
-  xbt_edge_t edge = NULL;
-
-  edge = xbt_new0(struct xbt_edge, 1);
+  xbt_edge_t edge = xbt_new0(struct xbt_edge, 1);
   xbt_dynar_push(src->out, &edge);
   if (g->directed)
     xbt_dynar_push(dst->in, &edge);
@@ -131,9 +124,7 @@ void xbt_graph_edge_set_data(xbt_edge_t edge, void *data)
  *
  * Free the graph structure.
  */
-void xbt_graph_free_graph(xbt_graph_t g,
-                          void_f_pvoid_t node_free_function,
-                          void_f_pvoid_t edge_free_function,
+void xbt_graph_free_graph(xbt_graph_t g, void_f_pvoid_t node_free_function, void_f_pvoid_t edge_free_function,
                           void_f_pvoid_t graph_free_function)
 {
   unsigned int cursor;
@@ -161,7 +152,6 @@ void xbt_graph_free_graph(xbt_graph_t g,
   free(g);
 }
 
-
 /** @brief Retrieve the graph's nodes as a dynar */
 xbt_dynar_t xbt_graph_get_nodes(xbt_graph_t g)
 {
@@ -209,33 +199,27 @@ double xbt_graph_edge_get_length(xbt_edge_t edge)
  *
  * From wikipedia:
  *
- * The Floyd–Warshall algorithm takes as input an adjacency matrix
- * representation of a weighted, directed graph (V, E). The weight of a
- * path between two vertices is the sum of the weights of the edges along
- * that path. The edges E of the graph may have negative weights, but the
- * graph must not have any negative weight cycles. The algorithm computes,
- * for each pair of vertices, the minimum weight among all paths between
- * the two vertices. The running time complexity is Θ(|V|3).
+ * The Floyd-Warshall algorithm takes as input an adjacency matrix representation of a weighted, directed graph (V, E).
+ * The weight of a path between two vertices is the sum of the weights of the edges along that path. The edges E of the
+ * graph may have negative weights, but the graph must not have any negative weight cycles. The algorithm computes, for
+ * each pair of vertices, the minimum weight among all paths between the two vertices. The running time complexity is
+ * Θ(|V|3).
  */
-void xbt_floyd_algorithm(xbt_graph_t g, double *adj, double *d,
-                         xbt_node_t * p)
+void xbt_floyd_algorithm(xbt_graph_t g, double *adj, double *d, xbt_node_t * p)
 {
-  unsigned long i, j, k;
-  unsigned long n;
-  n = xbt_dynar_length(g->nodes);
-
-# define D(u,v) d[(u)*n+(v)]
-# define P(u,v) p[(u)*n+(v)]
+  unsigned long i;
+  unsigned long j;
+  unsigned long k;
+  unsigned long n = xbt_dynar_length(g->nodes);
 
   for (i = 0; i < n * n; i++) {
     d[i] = adj[i];
   }
 
-
   for (i = 0; i < n; i++) {
     for (j = 0; j < n; j++) {
-      if (D(i, j) != -1) {
-        P(i, j) = *((xbt_node_t *) xbt_dynar_get_ptr(g->nodes, i));
+      if (d[i*n+j] > -1) {
+        p[i*n+j] = *((xbt_node_t *) xbt_dynar_get_ptr(g->nodes, i));
       }
     }
   }
@@ -243,31 +227,26 @@ void xbt_floyd_algorithm(xbt_graph_t g, double *adj, double *d,
   for (k = 0; k < n; k++) {
     for (i = 0; i < n; i++) {
       for (j = 0; j < n; j++) {
-        if ((D(i, k) != -1) && (D(k, j) != -1)) {
-          if ((D(i, j) == -1) || (D(i, j) > D(i, k) + D(k, j))) {
-            D(i, j) = D(i, k) + D(k, j);
-            P(i, j) = P(k, j);
-          }
+        if (d[i * n + k] > -1 && d[k * n + j] > -1 &&
+            (d[i * n + j] < 0 || d[i * n + j] > d[i * n + k] + d[k * n + j])) {
+          d[i * n + j] = d[i * n + k] + d[k * n + j];
+          p[i * n + j] = p[k * n + j];
         }
       }
     }
   }
-# undef P
-# undef D
 }
 
 /** @brief Export the given graph in the GraphViz formatting for visualization */
-void xbt_graph_export_graphviz(xbt_graph_t g, const char *filename,
-                               const char *(node_name) (xbt_node_t),
+void xbt_graph_export_graphviz(xbt_graph_t g, const char *filename, const char *(node_name) (xbt_node_t),
                                const char *(edge_name) (xbt_edge_t))
 {
   unsigned int cursor = 0;
   xbt_node_t node = NULL;
   xbt_edge_t edge = NULL;
-  FILE *file = NULL;
   const char *name = NULL;
 
-  file = fopen(filename, "w");
+  FILE *file = fopen(filename, "w");
   xbt_assert(file, "Failed to open %s \n", filename);
 
   if (g->directed)
@@ -278,8 +257,7 @@ void xbt_graph_export_graphviz(xbt_graph_t g, const char *filename,
   fprintf(file, "  graph [overlap=scale]\n");
 
   fprintf(file, "  node [shape=box, style=filled]\n");
-  fprintf(file,
-          "  node [width=.3, height=.3, style=filled, color=skyblue]\n\n");
+  fprintf(file, "  node [width=.3, height=.3, style=filled, color=skyblue]\n\n");
 
   xbt_dynar_foreach(g->nodes, cursor, node) {
     if (node_name){
@@ -297,17 +275,19 @@ void xbt_graph_export_graphviz(xbt_graph_t g, const char *filename,
     }else{
       c = c_ndir;
     }
-    const char *src_name, *dst_name;
     if (node_name){
-      src_name = node_name(edge->src);
-      dst_name = node_name(edge->dst);
+      const char *src_name = node_name(edge->src);
+      const char *dst_name = node_name(edge->dst);
       fprintf(file, "  \"%s\" %s \"%s\"", src_name, c, dst_name);
     }else{
       fprintf(file, "  \"%p\" %s \"%p\"", edge->src, c, edge->dst);
     }
 
-    if ((edge_name) && ((name = edge_name(edge))))
-      fprintf(file, "[label=\"%s\"]", name);
+    if (edge_name){
+      name = edge_name(edge);
+      if (name)
+        fprintf(file, "[label=\"%s\"]", name);
+    }
     fprintf(file, ";\n");
   }
   fprintf(file, "}\n");