Implement the most basic clear function and all "create node" functions.

src/libregex.c

@@ -1 +1,88 @@
-#include "libregex.h"
+#include "libregex.h"#include "libregex.h"
+#include <stdlib.h>
+#include <string.h>
+
+libregex_result _regex_node_create_clear(regex_node** node){
+  libregex_result result = LIBREGEX_SUCCESS;
+  *node = malloc(sizeof(**node));
+  if(*node){
+    regex_node_clear(*node);
+  } else {
+    result = LIBREGEX_MALLOC;
+  }
+  return result;
+}
+
+libregex_result _regex_node_create_value(regex_node** node, char value, regex_node* next){
+  libregex_result result = _regex_node_create_clear(node);
+  if(result == LIBREGEX_SUCCESS){
+    (*node)->type = REGEX_VALUE;
+    (*node)->data_u.value_s.value = value;
+    (*node)->data_u.value_s.next = next;
+  }
+  return result;
+}
+
+libregex_result _regex_node_create_range(regex_node** node, char from, char to, regex_node* next){
+  libregex_result result = _regex_node_create_clear(node);
+  if(result == LIBREGEX_SUCCESS){
+    (*node)->type = REGEX_RANGE;
+    (*node)->data_u.range_s.from = from;
+    (*node)->data_u.range_s.to = to;
+    (*node)->data_u.range_s.next = next;
+  }
+  return result;
+}
+
+libregex_result _regex_node_create_any(regex_node** node, regex_node* next){
+  libregex_result result = _regex_node_create_clear(node);
+  if(result == LIBREGEX_SUCCESS){
+    (*node)->type = REGEX_ANY;
+    (*node)->data_u.any_s.next = next;
+  }
+  return result;
+}
+
+libregex_result _regex_node_create_connect(regex_node** node, regex_node* next){
+  libregex_result result = _regex_node_create_clear(node);
+  if(result == LIBREGEX_SUCCESS){
+    (*node)->type = REGEX_CONNECT;
+    (*node)->data_u.connect_s.next = next;
+  }
+  return result;
+}
+
+libregex_result _regex_node_create_fork(regex_node** node, regex_node* left, regex_node* right){
+  libregex_result result = _regex_node_create_clear(node);
+  if(result == LIBREGEX_SUCCESS){
+    (*node)->type = REGEX_FORK;
+    (*node)->data_u.fork_s.left = left;
+    (*node)->data_u.fork_s.right = right;
+  }
+  return result;
+}
+
+libregex_result _regex_node_create_group(regex_node** open, regex_node** close, int group_id){
+  libregex_result result = _regex_node_create_clear(open);
+  if(result == LIBREGEX_SUCCESS){
+    result = _regex_node_create_clear(close);
+  }
+  if(result == LIBREGEX_SUCCESS){
+    (*open)->type = (*close)->type = REGEX_GROUP;
+    (*open)->data_u.group_s.id = (*close)->data_u.group_s.id = group_id;
+    (*open)->data_u.group_s.other = (*close);
+    (*close)->data_u.group_s.other = (*open);
+
+    (*open)->data_u.group_s.open = 1;
+  } else {
+    free(*open);
+    free(*close);
+  }
+  return result;
+}
+
+void regex_node_clear(regex_node* node){
+  node->type = REGEX_CLEAR;
+  node->list_id = -1;
+  memset(&node->data_u, 0, sizeof(node->data_u));
+}