tinyxml2 fuzzer update

projects/tinyxml2/fuzzer.cpp

@@ -0,0 +1,80 @@
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+#include <string>
+#include <vector>
+#include "tinyxml2/tinyxml2.h"
+
+using namespace tinyxml2;
+
+void fuzz_parse_xml(const uint8_t* data, size_t size) {
+    std::string xml(reinterpret_cast<const char*>(data), size);
+    XMLDocument doc;
+    doc.Parse(xml.c_str(), size);
+
+    XMLElement* root = doc.RootElement();
+    if (root) {
+        root->Name();
+        root->GetText();
+        root->GetDocument();
+
+        for (const XMLAttribute* attr = root->FirstAttribute(); attr; attr = attr->Next()) {
+            attr->Name();
+            attr->Value();
+        }
+
+        for (XMLElement* child = root->FirstChildElement(); child; child = child->NextSiblingElement()) {
+            child->Name();
+        }
+    }
+
+    doc.Print();
+    doc.Clear();
+}
+
+void fuzz_create_dom(const uint8_t* data, size_t size) {
+    std::string text(reinterpret_cast<const char*>(data), size);
+
+    XMLDocument doc;
+    XMLElement* root = doc.NewElement("root");
+    doc.InsertFirstChild(root);
+
+    XMLElement* child = doc.NewElement("child");
+    child->SetAttribute("id", 123);              // May invoke unsafe behavior
+    child->SetText(text.c_str());                // Direct pass without checking
+    root->InsertEndChild(child);
+
+    doc.SaveFile("/dev/null");
+    doc.Clear();
+}
+
+void fuzz_api_surface(const uint8_t* data, size_t size) {
+    XMLDocument doc;
+    XMLNode* decl = doc.NewDeclaration();
+    doc.InsertFirstChild(decl);
+
+    XMLUnknown* unknown = doc.NewUnknown("<!-- fuzz -->");
+    doc.InsertEndChild(unknown);
+
+    XMLText* textNode = doc.NewText("FuzzTest");
+    doc.InsertEndChild(textNode);
+
+    doc.ErrorID();
+    doc.ErrorStr();
+}
+
+void fuzz_error_classification() {
+    for (int i = 0; i < 100; ++i) {
+        const char* name = XMLDocument::ErrorIDToName(static_cast<XMLError>(i));
+        std::string s(name); // no null check
+    }
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    fuzz_parse_xml(data, size);
+    fuzz_create_dom(data, size);
+    fuzz_api_surface(data, size);
+    fuzz_error_classification();
+    return 0;
+}