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#include <assert.h>
#include <stdio.h>
#include <string.h>
#include "houdini.h"
/**
 * According to the OWASP rules:
 *
 * & --> &
 * < --> <
 * > --> >
 * " --> "
 * ' --> '     ' is not recommended
 * / --> /     forward slash is included as it helps end an HTML entity
 *
 */
static const char HTML_ESCAPE_TABLE[] = {
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 1, 0, 0, 0, 2, 3, 0, 0, 0, 0, 0, 0, 0, 4,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 6, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
static const char *HTML_ESCAPES[] = {
	"",
	""",
	"&",
	"'",
	"/",
	"<",
	">"
};
int
houdini_escape_html0(cmark_strbuf *ob, const uint8_t *src, size_t size, int secure)
{
	size_t  i = 0, org, esc = 0;
	while (i < size) {
		org = i;
		while (i < size && (esc = HTML_ESCAPE_TABLE[src[i]]) == 0)
			i++;
		if (i > org)
			cmark_strbuf_put(ob, src + org, i - org);
		/* escaping */
		if (unlikely(i >= size))
			break;
		/* The forward slash is only escaped in secure mode */
		if ((src[i] == '/' || src[i] == '\'') && !secure) {
			cmark_strbuf_putc(ob, src[i]);
		} else {
			cmark_strbuf_puts(ob, HTML_ESCAPES[esc]);
		}
		i++;
	}
	return 1;
}
int
houdini_escape_html(cmark_strbuf *ob, const uint8_t *src, size_t size)
{
	return houdini_escape_html0(ob, src, size, 1);
}
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