1 files changed, 87 insertions, 0 deletions
diff --git a/src/utils/gen_stack.c b/src/utils/gen_stack.c
new file mode 100644
index 0000000..76d8021
--- /dev/null
+++ b/src/utils/gen_stack.c
@@ -0,0 +1,87 @@
+/**
+ *  This program is free software: you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License as
+ *  published by the Free Software Foundation, either version 3 of the
+ *  License, or (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see
+ *  <http://www.gnu.org/licenses/>.
+ *
+ *  (c) Vincenzo Nicosia 2009-2017 -- <v.nicosia@qmul.ac.uk>
+ * 
+ *  This file is part of NetBunch, a package for complex network
+ *  analysis and modelling. For more information please visit:
+ *
+ *             http://www.complex-networks.net/
+ *
+ *  If you use this software, please add a reference to 
+ *
+ *               V. Latora, V. Nicosia, G. Russo             
+ *   "Complex Networks: Principles, Methods and Applications"
+ *              Cambridge University Press (2017) 
+ *                ISBN: 9781107103184
+ *
+ ***********************************************************************
+ *
+ *  Implementation of a stack data structure, which stores pointers to
+ *  generic objects
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "gen_stack.h"
+
+void gen_stack_create(gen_stack_t *s){
+  
+  s->size = 10;
+  s->head = -1;
+  s->v = malloc(s->size * sizeof(void*)); 
+  
+}
+
+void gen_stack_push(gen_stack_t *s, void *elem){
+  
+  //void ** tmp;
+  
+  if (s->head == s->size-1){
+    s->size += 10;
+    s->v = realloc(s->v, s->size * sizeof(void*));
+    if (!s->v){
+      fprintf(stderr, "Unable to allocate more memory in stack.c:stack_push... Exiting!\n");
+      exit(17);
+    }
+  }
+  s->head++;
+  s->v[s->head] = elem;
+}
+
+int gen_stack_pop(gen_stack_t *s, void  **res){
+
+  if (!gen_stack_empty(s)){
+    *res = s->v[s->head];
+    s->head--;
+    return 0;
+  }
+  else{
+    return -1;
+  }
+  
+}
+
+int gen_stack_empty(gen_stack_t *s){
+
+  return (s->head < 0 ? 1 : 0);
+}
+
+
+int gen_stack_size(gen_stack_t *s){
+  return s->head + 1;
+}