This is a major lift into C++.

Much of the code is now building in C++, and I'm using C++23.

A spot test seems to work.  Now I can start to debride all the
painful memory management quirks...

src/url.hh

@@ -0,0 +1,124 @@
+/*
+ * File : url.h - Dillo
+ *
+ * Copyright (C) 2001 Jorge Arellano Cid <jcid@dillo.org>
+ *
+ */
+
+/** @file
+ * Parse and normalize all URL's inside Dillo.
+ */
+
+#ifndef __URL_H__
+#define __URL_H__
+
+#include "d_size.h"
+#include "../dlib/dlib.h"
+
+
+#define URL_HTTP_PORT        80
+#define URL_HTTPS_PORT       443
+
+/* for a_Url_host_type() */
+#define URL_HOST_ERROR      -1
+#define URL_HOST_NAME        0
+#define URL_HOST_IPV4        1
+#define URL_HOST_IPV6        2
+
+/*
+ * Values for DilloUrl->flags.
+ * Specifies which which action to perform with an URL.
+ */
+#define URL_Get                 (1 << 0)
+#define URL_Post                (1 << 1)
+
+#define URL_E2EQuery            (1 << 5)
+#define URL_ReloadPage          (1 << 7)
+#define URL_ReloadFromCache     (1 << 8)
+
+#define URL_IgnoreScroll        (1 << 9)
+#define URL_SpamSafe            (1 << 10)
+
+#define URL_MultipartEnc        (1 << 11)
+
+/*
+ * Access methods to fields inside DilloURL.
+ * (non '_'-ended macros MUST use these for initialization sake)
+ */
+/* these MAY return NULL: */
+#define URL_SCHEME_(u)              (u)->scheme
+#define URL_AUTHORITY_(u)           (u)->authority
+#define URL_PATH_(u)                (u)->path
+#define URL_QUERY_(u)               (u)->query
+#define URL_FRAGMENT_(u)            (u)->fragment
+#define URL_HOST_(u)                a_Url_hostname(u)
+#define URL_STR_(u)                 a_Url_str(u)
+/* this returns a Dstr* */
+#define URL_DATA_(u)                (u)->data
+/* these return an integer */
+#define URL_PORT_(u)                (URL_HOST(u), (u)->port)
+#define URL_FLAGS_(u)               (u)->flags
+#define URL_ILLEGAL_CHARS_(u)       (u)->illegal_chars
+#define URL_ILLEGAL_CHARS_SPC_(u)   (u)->illegal_chars_spc
+
+/*
+ * Access methods that never return NULL.
+ * When the "empty" and "undefined" concepts of RFC-2396 are irrelevant to
+ * the caller, and a string is required, use these methods instead:
+ */
+#define NPTR2STR(p)                 ((p) ? (p) : "")
+#define URL_SCHEME(u)               NPTR2STR(URL_SCHEME_(u))
+#define URL_AUTHORITY(u)            NPTR2STR(URL_AUTHORITY_(u))
+#define URL_PATH(u)                 NPTR2STR(URL_PATH_(u))
+#define URL_QUERY(u)                NPTR2STR(URL_QUERY_(u))
+#define URL_FRAGMENT(u)             NPTR2STR(URL_FRAGMENT_(u))
+#define URL_HOST(u)                 NPTR2STR(URL_HOST_(u))
+#define URL_STR(u)                  NPTR2STR(URL_STR_(u))
+#define URL_DATA(u)                 URL_DATA_(u)
+#define URL_PORT(u)                 URL_PORT_(u)
+#define URL_FLAGS(u)                URL_FLAGS_(u)
+#define URL_ILLEGAL_CHARS(u)        URL_ILLEGAL_CHARS_(u)
+#define URL_ILLEGAL_CHARS_SPC(u)    URL_ILLEGAL_CHARS_SPC_(u)
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+typedef struct {
+   Dstr  *url_string;
+   const char *buffer;
+   const char *scheme;            /**/
+   const char *authority;         /**/
+   const char *path;              /* These are references only */
+   const char *query;             /* (no need to free them) */
+   const char *fragment;          /**/
+   const char *hostname;          /**/
+   int port;
+   int flags;
+   Dstr *data;                    /**< POST */
+   int ismap_url_len;             /**< Used by server side image maps */
+   int illegal_chars;             /**< number of illegal chars */
+   int illegal_chars_spc;         /**< number of illegal space chars */
+} DilloUrl;
+
+
+DilloUrl* a_Url_new(const char *url_str, const char *base_url);
+void a_Url_free(DilloUrl *u);
+char *a_Url_str(const DilloUrl *url);
+const char *a_Url_hostname(const DilloUrl *u);
+DilloUrl* a_Url_dup(const DilloUrl *u);
+int a_Url_cmp(const DilloUrl *A, const DilloUrl *B);
+void a_Url_set_flags(DilloUrl *u, int flags);
+void a_Url_set_data(DilloUrl *u, Dstr **data);
+void a_Url_set_ismap_coords(DilloUrl *u, char *coord_str);
+char *a_Url_decode_hex_str(const char *str);
+char *a_Url_encode_hex_str(const char *str);
+char *a_Url_string_strip_delimiters(const char *str);
+int a_Url_host_type(const char *host);
+bool_t a_Url_same_organization(const DilloUrl *u1, const DilloUrl *u2);
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* __URL_H__ */