src/model.c: making node research efficient and safe

src/model.c

@@ -2,7 +2,7 @@
 //  Model management module                                                  //
 //                                                                           //
 //  Copyright © 2021 Libre en Communs (contact@a-lec.org)                    //
-//  Copyright © 2021 Adrien Bourmault (neox@a-lec.org)                       //
+//  Copyright © 2021-2024 Adrien Bourmault (neox@a-lec.org)                       //
 //                                                                           //
 //  This file is part of gem-graph.                                          //
 //                                                                           //
@@ -40,85 +40,49 @@ struct model_t *knownModels = NULL;
 
 /* -------------------------------------------------------------------------- */
 
-static inline xmlNodePtr getNextChild (xmlNodePtr node, xmlChar *last)
+/*
-{
+ * Finds a node by a path of tags.
-    while (node != NULL && xmlStrcmp(node->name, last)) {
+ *
-        // //printf("   <>--- line n°%lu   <%s>\n", xmlGetLineNo(node), node->name);
+ * @param node The starting node for the search.
-        node = node->next;
+ * @param path The path to the tag, with '/' as the delimiter.
+ * @return The content of the tag at the end of the path, or NULL if not found.
+ */
+char* model_find_node_by_path(xmlNode *node, const char *path) {
+    char *pathCopy = strdup(path); // Duplicate path to modify it
+    char *tag = strtok(pathCopy, "/"); // Get the first tag in the path
+    xmlNode *currentNode = node;
+
+    while (tag != NULL && currentNode != NULL) {
+        xmlNode *foundNode = NULL;
+
+        // Search for the tag at the current level
+        for (xmlNode *child = currentNode->children; child; child = child->next) {
+            if (child->type == XML_ELEMENT_NODE && strcmp((const char *)child->name, tag) == 0) {
+                foundNode = child; // Tag found at the current level
+                break;
             }
-    return node;
         }
 
-static inline xmlChar* splitStrAtSlash (xmlChar *toSplit)
+        tag = strtok(NULL, "/"); // Move to the next tag in the path
-{
-    toSplit = (xmlChar *)xmlStrchr(toSplit, '/');
-    toSplit = xmlStrsub (toSplit, 1, xmlStrlen(toSplit));
-    return toSplit;
-}
 
-static inline xmlChar* getFirstTag (xmlChar *path)
+        // If there are more tags to find, continue with the found node's children
-{
+        if (tag != NULL && foundNode != NULL) {
-    xmlChar *preop = path;
+            currentNode = foundNode;
-    path = (xmlChar *)xmlStrchr(path, '/');
-    path = xmlStrsub (path, 1, xmlStrlen(path));
-
-    return  xmlStrsub (preop, 0, xmlStrlen(preop) - xmlStrlen(path) - 1);
-}
-
-static inline xmlChar* getLastTag (xmlChar *path)
-{
-    while ((ulong)xmlStrchr (path, '/'))
-        path = splitStrAtSlash ((xmlChar *)path);
-
-    // //printf("last tag in the path = <%s>\n", path);
-    return path; // which is no more the given path but only its last tag !
-}
-
-/* -------------------------------------------------------------------------- */
-
-static xmlNodePtr model_get_node (struct model_t *self, xmlChar *path)
-{
-    xmlNodePtr node;
-    xmlChar *extrait;
-    xmlChar *reste, *last, *affich;
-
-    // Lookup for node from path in hash table
-    node = xmlHashLookup(self->hashtable, path);
-
-    // Found a node in hash table
-    if (node) {
-        return node;
-
-    // no node found in hash table
         } else {
-        reste = path;
+            // If this was the last tag, try to get its content
-        affich = reste;
+            if (foundNode != NULL && tag == NULL) {
-        last = getLastTag(reste);
+                char *content = (char *)xmlNodeGetContent(foundNode);
-        node = xmlDocGetRootElement(self->doc);
+                free(pathCopy);
-
+                return content;
-        while (xmlStrchr (reste, '/')) {
-            extrait = getFirstTag(reste);
-            reste = splitStrAtSlash((xmlChar *)reste);
-            node = node->xmlChildrenNode;
-            node = getNextChild(node, extrait);
             }
 
-        if(node && xmlStrcmp(node->name, last)) {
+            currentNode = NULL; // End loop if tag not found
-            node = node->xmlChildrenNode;
-
-            while (node && xmlStrcmp(node->name, last)) {
-                node = node->next;
         }
-            xmlHashAddEntry (self->hashtable, path, node);
     }
 
-        return node;
+    free(pathCopy);
-
+    return NULL; // Path not fully matched
 }
-
-    return NULL;
-}
-
 /* -------------------------------------------------------------------------- */
 
 static inline long model_get_node_long_attrib (xmlNodePtr node, char *id)