Extract a to_s function

1 files changed, 24 insertions, 7 deletions

diff --git a/src/01/02b/doubly_linked_list.c b/src/01/02b/doubly_linked_list.c
index 86fb1ce..cc18a71 100644
--- a/src/01/02b/doubly_linked_list.c
+++ b/src/01/02b/doubly_linked_list.c
@@ -1,6 +1,7 @@
 #include "doubly_linked_list.h"
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 /**
  * The equivalent of a constructor
@@ -136,18 +137,34 @@ void swap(Node *x, Node *y) {
 }
 
 /**
- * Prints the previous, data and next pointers for a node
+ * Generates a string representation of the Node usable for printing to stdout
  *
- * @param node The node to print
+ * @param node The node to represent as a string
+ * @return The string that represents the node
  */
-static void print(Node *node) {
+char *to_s(Node *node) {
+  const int buffer_size = 32;
+  char *buffer = malloc(buffer_size);
+  memset(buffer, buffer_size, '\0');
+
   if (node->prev && node->next)
-    printf("(%d<%d>%d)", node->prev->data, node->data, node->next->data);
+    snprintf(buffer, buffer_size, "(%d<%d>%d) ", node->prev->data, node->data, node->next->data);
   else if (node->next)
-    printf("(nil<%d>%d)", node->data, node->next->data);
+    snprintf(buffer, buffer_size, "(nil<%d>%d) ", node->data, node->next->data);
   else
-    printf("(%d<%d>nil)", node->prev->data, node->data);
-  printf(" ");
+    snprintf(buffer, buffer_size, "(%d<%d>nil) ", node->prev->data, node->data);
+  return buffer;
+}
+
+/**
+ * Prints the previous, data and next pointers for a node
+ *
+ * @param node The node to print
+ */
+static void print(Node *node) {
+  char *message = to_s(node);
+  printf("%s", message);
+  free(message);
 }
 
 /**