src: refactor EndsInANumber in node_url.cc and adds IsIPv4NumberValid

src/node_url.cc

@@ -407,29 +407,86 @@ int64_t ParseIPv4Number(const char* start, const char* end) {
   return strtoll(start, nullptr, R);
 }
 
+// https://url.spec.whatwg.org/#ipv4-number-parser
+bool IsIPv4NumberValid(std::string_view input) {
+  // If input is the empty string, then return failure.
+  if (input.empty()) {
+    return false;
+  }
+
+  // If input contains at least two code points..
+  if (input.size() >= 2) {
+    // and the first two code points are either "0X" or "0x", then:
+    if (input[0] == '0' && (input[1] == 'X' || input[1] == 'x')) {
+      if (input.size() == 2) {
+        return true;
+      }
+
+      // Remove the first two code points from input,
+      // radix-R is 16
+      // If input contains a code point that is not a radix-R digit, then return
+      // failure.
+      return input.find_first_not_of("0123456789abcdefABCDEF", 2) ==
+             std::string_view::npos;
+
+      // and the first code point is U+0030 (0), then:
+    } else if (input[0] == '0') {
+      if (input.size() == 1) {
+        return true;
+      }
+
+      // Remove the first code point from input.
+      // radix-R is 8
+      // If input contains a code point that is not a radix-R digit, then return
+      // failure.
+      return input.find_first_not_of("01234567", 1) == std::string_view::npos;
+    }
+  }
+
+  // If input contains a code point that is not a radix-R digit, then return
+  // failure. radix-R is 10
+  return std::all_of(input.begin(), input.end(), ::isdigit);
+}
+
 // https://url.spec.whatwg.org/#ends-in-a-number-checker
-bool EndsInANumber(const std::string& input) {
-  std::vector<std::string> parts = SplitString(input, '.', false);
+bool EndsInANumber(const std::string_view input) {
+  if (input.empty()) {
+    return false;
+  }
+
+  const std::string delimiter = ".";
+  auto pointer_start = input.begin();
+  auto pointer_end = input.end();
 
-  if (parts.empty()) return false;
+  uint8_t parts_size = std::count(pointer_start, pointer_end, delimiter[0]);
+  ++parts_size;
 
-  if (parts.back().empty()) {
-    if (parts.size() == 1) return false;
-    parts.pop_back();
+  // If the last item in parts is the empty string, then:
+  if (input.back() == delimiter[0]) {
+    // Remove the last item from parts.
+    --pointer_end;
+    --parts_size;
   }
 
-  const std::string& last = parts.back();
+  // Let last be the last item in parts
+  if (parts_size > 1) {
+    pointer_start = std::find_end(
+        pointer_start, pointer_end, delimiter.begin(), delimiter.end());
+    ++pointer_start;
+  }
 
-  // If last is non-empty and contains only ASCII digits, then return true
-  if (!last.empty() && std::all_of(last.begin(), last.end(), ::isdigit)) {
-    return true;
+  if (std::distance(pointer_start, pointer_end) == 0) {
+    return false;
   }
 
-  const char* last_str = last.c_str();
-  int64_t num = ParseIPv4Number(last_str, last_str + last.size());
-  if (num >= 0) return true;
+  // If last is non-empty and contains only ASCII digits, then return true.
+  if (std::all_of(pointer_start, pointer_end, ::isdigit)) {
+    return true;
+  }
 
-  return false;
+  // If parsing last as an IPv4 number does not return failure, then return
+  // true.
+  return IsIPv4NumberValid(std::string(pointer_start, pointer_end));
 }
 
 void URLHost::ParseIPv4Host(const char* input, size_t length) {
@@ -1944,4 +2001,4 @@ MaybeLocal<Value> URL::ToObject(Environment* env) const {
 }  // namespace node
 
 NODE_BINDING_CONTEXT_AWARE_INTERNAL(url, node::url::Initialize)
-NODE_BINDING_EXTERNAL_REFERENCE(url, node::url::RegisterExternalReferences)
+NODE_BINDING_EXTERNAL_REFERENCE(url, node::url::RegisterExternalReferences)