Module header 

Strict building blocks for HTTP field maps.

These helpers implement the field-line handling used by the higher-level extractors. They deliberately do not combine repeated lines unless the field-specific extractor owns that grammar. See RFC 9110, Section 5 for HTTP field semantics.

Functions

append_header_value

Append one already validated field value without replacing existing values.

extract_single_header_text

Extract a singular field as text without silently discarding invalid bytes.

extract_single_header_value

Extract a field value only when the field has at most one field line.