Graph

Graph/c_TransitiveClosure.c

@@ -0,0 +1,51 @@
+#include <c_TransitiveClosure.h>
+
+c_err_t c_TransitiveClosure_Init(c_TransitiveClosure_t* self, c_Digraph_t* graph, c_Allocator_t* allocator) {
+    if (!self || !graph) return C_ERR_PARAM;
+
+    self->allocator = allocator ? *allocator : c_DefaultAllocator;
+    self->V = graph->V;
+    self->dfs_matrix = NULL;
+
+    if (self->V == 0) return C_SUCCESS;
+
+    /* 1. Allocate an array of non-recursive DFS structures */
+    self->dfs_matrix = (c_NonrecursiveDirectedDFS_t*)c_Allocator_Calloc(
+        &self->allocator,
+        self->V,
+        sizeof(c_NonrecursiveDirectedDFS_t)
+    );
+    if (!self->dfs_matrix) return C_ERR_NOMEM;
+
+    /* 2. Run a non-recursive DFS starting from each individual vertex */
+    for (c_size_t v = 0; v < self->V; ++v) {
+        c_err_t err = c_NonrecursiveDirectedDFS_Init(&self->dfs_matrix[v], graph, v, allocator);
+
+        if (err != C_SUCCESS) {
+            /* Clean up previously initialized instances to avoid memory leaks if OOM occurs mid-way */
+            for (c_size_t i = 0; i < v; ++i) {
+                c_NonrecursiveDirectedDFS_Destroy(&self->dfs_matrix[i]);
+            }
+            c_Allocator_Free(&self->allocator, self->dfs_matrix);
+            self->dfs_matrix = NULL;
+            self->V = 0;
+            return err;
+        }
+    }
+
+    return C_SUCCESS;
+}
+
+void c_TransitiveClosure_Destroy(c_TransitiveClosure_t* self) {
+    if (!self) return;
+
+    if (self->dfs_matrix) {
+        /* Deallocate every independent tracking instance matrix block */
+        for (c_size_t i = 0; i < self->V; ++i) {
+            c_NonrecursiveDirectedDFS_Destroy(&self->dfs_matrix[i]);
+        }
+        c_Allocator_Free(&self->allocator, self->dfs_matrix);
+        self->dfs_matrix = NULL;
+    }
+    self->V = 0;
+}