Lightweight HTML/XML extraction: links, forms, and sitemap URLs. More...

#include "nilorea/n_list.h"
#include "nilorea/n_str.h"
#include <stddef.h>

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Data Structures
struct	N_FORM_FIELD
	a single form field (input, select, textarea, button) More...

struct	N_HTML_FORM
	a parsed HTML form with its fields More...

Functions
LIST *	n_html_extract_forms (const char *html, size_t len)
	extract forms as a LIST of N_HTML_FORM*; free with n_html_forms_free

LIST *	n_html_extract_js_urls (const char *js, size_t len)
	extract URL/path tokens from JavaScript source (quoted string literals that look like an http(s) URL, a protocol-relative "//host" URL, or a "/" / "./" / "../" path; a "${...}" template is truncated to its static prefix), deduped, as a LIST of N_STR*; free with n_html_links_free.

LIST *	n_html_extract_links (const char *html, size_t len)
	extract link URLs (a/href, form/action, img/src, script/src, link/href, iframe/src) as a LIST of N_STR*; free with n_html_links_free

LIST *	n_html_extract_scripts (const char *html, size_t len)
	extract the inline <script> bodies (those without a src attribute) from an HTML document as a LIST of N_STR*; free with n_html_links_free.

void	n_html_forms_free (LIST **forms)
	free a list returned by n_html_extract_forms

void	n_html_links_free (LIST **links)
	free a list returned by n_html_extract_links or n_sitemap_extract_urls

N_STR *	n_html_to_text (const char *html, size_t len)
	render HTML to readable plain text: drop tags, skip script/style, decode common entities, collapse whitespace, and line-break block elements; returns a new N_STR (free with free_nstr) or NULL

LIST *	n_sitemap_extract_urls (const char *xml, size_t len)
	extract <loc> URLs from a sitemap.xml as a LIST of N_STR*; free with n_html_links_free

Detailed Description

Lightweight HTML/XML extraction: links, forms, and sitemap URLs.

Author: Castagnier Mickael

Version: 1.0

Date: 2026

A small, dependency-free tag scanner (not a full HTML parser) that pulls the link, form, and sitemap surface out of a document for a web crawler. It is tolerant of malformed markup and never executes anything.

Definition in file n_html.h.

Data Structure Documentation

◆ N_FORM_FIELD

struct N_FORM_FIELD

a single form field (input, select, textarea, button)

Examples: ex_html.c.

Definition at line 45 of file n_html.h.

Collaboration diagram for N_FORM_FIELD:

Data Fields
char *	name	field name attribute, or ""
int	required	1 when the required attribute is present
char *	type	field type (lowercased), default "text"
char *	value	default value attribute, or ""

◆ N_HTML_FORM

struct N_HTML_FORM

a parsed HTML form with its fields

Examples: ex_html.c.

Definition at line 53 of file n_html.h.

Collaboration diagram for N_HTML_FORM:

Data Fields
char *	action	action attribute (may be "" for self)
char *	enctype	lower-case enctype, default "application/x-www-form-urlencoded"
LIST *	fields	list of N_FORM_FIELD*
char *	method	upper-case method, default "GET"

Function Documentation

◆ n_html_extract_forms()

LIST * n_html_extract_forms	(	const char *	html,
		size_t	len
	)

extract forms as a LIST of N_HTML_FORM*; free with n_html_forms_free

Definition at line 392 of file n_html.c.

References _n_form_field_free(), _n_html_attr_lookup(), _n_html_form_free(), _n_html_scan_tags(), _n_html_strdup_upper(), _n_html_strndup(), _n_html_strndup_lower(), N_HTML_FORM::action, N_HTML_TAG_::closing, N_HTML_FORM::enctype, N_HTML_FORM::fields, list_destroy(), list_foreach, list_push(), Malloc, MAX_LIST_ITEMS, N_HTML_FORM::method, N_FORM_FIELD::name, N_HTML_TAG_::name, new_generic_list(), N_FORM_FIELD::required, N_FORM_FIELD::type, and N_FORM_FIELD::value.

Referenced by test_empty_and_null(), test_enctype(), and test_forms().

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◆ n_html_extract_js_urls()

LIST * n_html_extract_js_urls	(	const char *	js,
		size_t	len
	)

extract URL/path tokens from JavaScript source (quoted string literals that look like an http(s) URL, a protocol-relative "//host" URL, or a "/" / "./" / "../" path; a "${...}" template is truncated to its static prefix), deduped, as a LIST of N_STR*; free with n_html_links_free.

Recovers fetch()/XHR/route endpoints a static link scan misses.

Definition at line 915 of file n_html.c.

References _n_html_push_js_url(), MAX_LIST_ITEMS, and new_generic_list().

Referenced by test_js_urls(), and test_scripts().

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◆ n_html_extract_links()

LIST * n_html_extract_links	(	const char *	html,
		size_t	len
	)

extract link URLs (a/href, form/action, img/src, script/src, link/href, iframe/src) as a LIST of N_STR*; free with n_html_links_free

Definition at line 360 of file n_html.c.

References _n_html_attr_lookup(), _n_html_push_link(), _n_html_scan_tags(), N_HTML_TAG_::closing, list_destroy(), list_foreach, MAX_LIST_ITEMS, N_HTML_TAG_::name, and new_generic_list().

Referenced by test_empty_and_null(), and test_links().

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◆ n_html_extract_scripts()

LIST * n_html_extract_scripts	(	const char *	html,
		size_t	len
	)

extract the inline <script> bodies (those without a src attribute) from an HTML document as a LIST of N_STR*; free with n_html_links_free.

Feed each to n_html_extract_js_urls to mine inline endpoints.

Definition at line 941 of file n_html.c.

References _n_html_find_ci(), char_to_nstr_ex(), free_nstr_ptr(), list_push(), MAX_LIST_ITEMS, and new_generic_list().

Referenced by test_scripts().

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◆ n_html_forms_free()

void n_html_forms_free ( LIST ** forms )

free a list returned by n_html_extract_forms

Definition at line 984 of file n_html.c.

References list_destroy().

Referenced by test_empty_and_null(), test_enctype(), and test_forms().

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◆ n_html_links_free()

void n_html_links_free ( LIST ** links )

free a list returned by n_html_extract_links or n_sitemap_extract_urls

Definition at line 979 of file n_html.c.

References list_destroy().

Referenced by test_empty_and_null(), test_js_urls(), test_links(), test_scripts(), and test_sitemap().

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◆ n_html_to_text()

N_STR * n_html_to_text	(	const char *	html,
		size_t	len
	)

render HTML to readable plain text: drop tags, skip script/style, decode common entities, collapse whitespace, and line-break block elements; returns a new N_STR (free with free_nstr) or NULL

Definition at line 627 of file n_html.c.

References _n_html_block_kind(), _n_html_entities, _n_html_flush(), _n_html_lc(), _n_html_put_cp(), _n_html_put_str(), char_to_nstr_ex(), Free, LOG_ERR, Malloc, and n_log.