1 files changed, 112 insertions, 0 deletions
diff --git a/src/houdini_html_u.c b/src/houdini_html_u.c
new file mode 100644
index 0000000..b88b9d1
--- /dev/null
+++ b/src/houdini_html_u.c
@@ -0,0 +1,112 @@
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "buffer.h"
+#include "houdini.h"
+#include "utf8.h"
+#include "html_unescape.h"
+
+size_t
+houdini_unescape_ent(strbuf *ob, const uint8_t *src, size_t size)
+{
+	size_t i = 0;
+
+	if (size > 3 && src[0] == '#') {
+		int codepoint = 0;
+
+		if (_isdigit(src[1])) {
+			for (i = 1; i < size && _isdigit(src[i]); ++i) {
+				int cp = (codepoint * 10) + (src[i] - '0');
+
+				if (cp < codepoint)
+					return 0;
+
+				codepoint = cp;
+			}
+		}
+
+		else if (src[1] == 'x' || src[1] == 'X') {
+			for (i = 2; i < size && _isxdigit(src[i]); ++i) {
+				int cp = (codepoint * 16) + ((src[i] | 32) % 39 - 9);
+
+				if (cp < codepoint)
+					return 0;
+
+				codepoint = cp;
+			}
+		}
+
+		if (i < size && src[i] == ';' && codepoint) {
+			utf8proc_encode_char(codepoint, ob);
+			return i + 1;
+		}
+	}
+
+	else {
+		if (size > MAX_WORD_LENGTH)
+			size = MAX_WORD_LENGTH;
+
+		for (i = MIN_WORD_LENGTH; i < size; ++i) {
+			if (src[i] == ' ')
+				break;
+
+			if (src[i] == ';') {
+				const struct html_ent *entity = find_entity((char *)src, i);
+
+				if (entity != NULL) {
+					strbuf_put(ob, entity->utf8, entity->utf8_len);
+					return i + 1;
+				}
+
+				break;
+			}
+		}
+	}
+
+	return 0;
+}
+
+int
+houdini_unescape_html(strbuf *ob, const uint8_t *src, size_t size)
+{
+	size_t  i = 0, org, ent;
+
+	while (i < size) {
+		org = i;
+		while (i < size && src[i] != '&')
+			i++;
+
+		if (likely(i > org)) {
+			if (unlikely(org == 0)) {
+				if (i >= size)
+					return 0;
+
+				strbuf_grow(ob, HOUDINI_UNESCAPED_SIZE(size));
+			}
+
+			strbuf_put(ob, src + org, i - org);
+		}
+
+		/* escaping */
+		if (i >= size)
+			break;
+
+		i++;
+
+		ent = houdini_unescape_ent(ob, src + i, size - i);
+		i += ent;
+
+		/* not really an entity */
+		if (ent == 0)
+			strbuf_putc(ob, '&');
+	}
+
+	return 1;
+}
+
+void houdini_unescape_html_f(strbuf *ob, const uint8_t *src, size_t size)
+{
+	if (!houdini_unescape_html(ob, src, size))
+		strbuf_put(ob, src, size);
+}