From a888c34dbb345f561fe901f2deb1472a1096d633 Mon Sep 17 00:00:00 2001
From: Thomas Porzelt <tp@cryosphere.de>
Date: Thu, 5 Mar 2009 00:19:55 +0100
Subject: [PATCH] add encoding functions

---
 include/lighttpd/base.h     |   1 +
 include/lighttpd/encoding.h |  17 ++++++
 src/encoding.c              | 107 ++++++++++++++++++++++++++++++++++++
 src/wscript                 |   1 +
 4 files changed, 126 insertions(+)
 create mode 100644 include/lighttpd/encoding.h
 create mode 100644 src/encoding.c

diff --git a/include/lighttpd/base.h b/include/lighttpd/base.h
index b0a418d..1d0204a 100644
--- a/include/lighttpd/base.h
+++ b/include/lighttpd/base.h
@@ -51,6 +51,7 @@
 #include <lighttpd/filter_chunked.h>
 #include <lighttpd/collect.h>
 #include <lighttpd/network.h>
+#include <lighttpd/encoding.h>
 #include <lighttpd/utils.h>
 
 #define SERVER_VERSION ((guint) 0x01FF0000)
diff --git a/include/lighttpd/encoding.h b/include/lighttpd/encoding.h
new file mode 100644
index 0000000..fe0ad82
--- /dev/null
+++ b/include/lighttpd/encoding.h
@@ -0,0 +1,17 @@
+#ifndef _LIGHTTPD_ENCODING_H_
+#define _LIGHTTPD_ENCODING_H_
+
+#ifndef _LIGHTTPD_BASE_H_
+#error Please include <lighttpd/base.h> instead of this file
+#endif
+
+typedef enum {
+	ENCODING_HEX,  /* a => 61 */
+	ENCODING_HTML  /* HTML special chars. & => &amp; e.g. */
+} encoding_t;
+
+
+/* encodes special characters in a string and returns the new string */
+GString *string_encode(const gchar *str, encoding_t encoding);
+
+#endif
\ No newline at end of file
diff --git a/src/encoding.c b/src/encoding.c
new file mode 100644
index 0000000..9a85656
--- /dev/null
+++ b/src/encoding.c
@@ -0,0 +1,107 @@
+#include <lighttpd/base.h>
+
+static const gchar hex_chars[] = "0123456789abcdef";
+
+/* HEX */
+static const gchar encode_map_hex[] = {
+	/*
+	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
+	*/
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 00 - 0F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 10 - 1F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 20 - 2F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 30 - 3F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 40 - 40 */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 50 - 50 */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 60 - 60 */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 70 - 70 */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 80 - 8F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 90 - 9F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* A0 - AF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* B0 - BF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* C0 - CF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* D0 - DF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* E0 - EF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* F0 - FF */
+};
+
+/* HTML */
+static const gchar encode_map_html[] = {
+	/*
+	0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
+	*/
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 00 - 0F control chars */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 10 - 1F */
+	0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 20 - 2F & */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, /* 30 - 3F < > */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 40 - 40 */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 50 - 50 */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 60 - 60 */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, /* 70 - 70 DEL */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 80 - 8F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 90 - 9F */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* A0 - AF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* B0 - BF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* C0 - CF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* D0 - DF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* E0 - EF */
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* F0 - FF */
+};
+
+GString *string_encode(const gchar *str, encoding_t encoding) {
+	/* replace html chars with &#xHH; */
+	GString *result;
+	guchar *c;
+	guchar *pos;
+	gsize new_len = 0;
+	guint encoded_len = 0;
+	const gchar *map = NULL;
+
+	switch (encoding) {
+	case ENCODING_HTML:
+		map = encode_map_html;
+		encoded_len = 6;
+		break;
+	case ENCODING_HEX:
+		map = encode_map_hex;
+		encoded_len = 2;
+		break;
+	}
+
+	/* check how many chars need to be encoded */
+	for (c = (guchar*)str; *c != '\0'; c++) {
+		if (map[*c])
+			new_len += encoded_len;
+		else
+			new_len++;
+	}
+
+	result = g_string_sized_new(new_len);
+
+	for (c = (guchar*)str, pos = (guchar*)result->str; *c != '\0'; c++) {
+		if (map[*c]) {
+			/* char needs to be encoded */
+			switch (encoding) {
+			case ENCODING_HTML:
+				/* &#xHH */
+				*pos++ = '&';
+				*pos++ = '#';
+				*pos++ = 'x';
+				*pos++ = hex_chars[((*c) >> 4) & 0x0F];
+				*pos++ = hex_chars[(*c) & 0x0F];
+				*pos++ = ';';
+				break;
+			case ENCODING_HEX:
+				*pos++ = hex_chars[((*c) >> 4) & 0x0F];
+				*pos++ = hex_chars[(*c) & 0x0F];
+			}
+		} else {
+			/* no encoding needed */
+			*pos++ = *c;
+		}
+	}
+
+	*pos = '\0';
+
+	return result;
+}
\ No newline at end of file
diff --git a/src/wscript b/src/wscript
index 2e04162..3d91507 100644
--- a/src/wscript
+++ b/src/wscript
@@ -26,6 +26,7 @@ common_src = '''
 	condition_parsers.rl
 	config_parser.rl
 	connection.c
+	encoding.c
 	environment.c
 	filter_chunked.c
 	http_headers.c