Module validation 

DTD validation (§27, §85 Phase 6).

DTD validation against element/attribute declarations:

1. Element content model validation — does the element’s child sequence match its declared content model?
2. Attribute value validation — does each attribute’s value conform to its declared type (CDATA, ID, IDREF, IDREFS, ENTITY, ENTITIES, NMTOKEN, NMTOKENS, ENUMERATION, NOTATION)?
3. ID/IDREF consistency — are all ID values unique? Does each IDREF reference a valid ID?
4. Required attributes — are all REQUIRED attributes present?
5. NOTATION validation — are NOTATION attributes referencing declared notations?
6. Well-formedness constraints — additional validity constraints

UPSTREAM-PARITY

This module follows libxml2’s valid.c implementation. The validation context (xmlValidCtxt) accumulates ID/IDREF tables across the document and checks consistency in xmlValidateDocumentFinal.

Phase 6 status

Complete — all core DTD validation functions are implemented. Edge-case behavior for degenerate DTDs matches upstream.

Functions

free_valid_ctxt^⚠

Free a validation context.

is_empty_element^⚠

Check if an element is declared as EMPTY.

is_mixed_element^⚠

Check if an element has a mixed content model.

new_valid_ctxt^⚠

Create a new validation context.

set_valid_errors^⚠

Set error and warning callbacks on a validation context.

validate_attribute_decl^⚠

Validate an attribute’s value against its declaration.

validate_attribute_value^⚠

Validate an attribute value against its declared type.

validate_content^⚠

Validate the content of an element node against its content model.

validate_document^⚠

Validate an entire document against its DTD.

validate_document_final^⚠

Final validation: check that all IDREFs resolve to existing IDs.

validate_dtd^⚠

Validate a DTD’s declarations (element/attribute declarations).

validate_dtd_final^⚠

Final DTD validation — checks ID/IDREF consistency.

validate_element^⚠

Validate a single element node against its DTD element and attribute declarations.

validate_enumeration^⚠

Validate that value is one of the values in the enumeration.

validate_id^⚠

Validate an ID value: check that the value is a valid XML Name and that no duplicate ID values exist in the document.

validate_id_ref^⚠

Validate an IDREF value: check that the referenced ID exists in the document.

validate_id_refs^⚠

Validate IDREFS (whitespace-separated list of IDREF values).

validate_name^⚠

Validate whether value is a valid XML Name.

validate_names^⚠

Validate whether value is a whitespace-separated list of XML Names.

validate_nmtoken^⚠

Validate whether value is a valid XML NMTOKEN.

validate_nmtokens^⚠

Validate whether value is a whitespace-separated list of XML NMTOKENs.

validate_notation_use^⚠

Validate that notationName is a declared notation in the document’s DTD.

validate_root^⚠

Validate the root element of a document.