Utf8 Badge Fix And URL Parser International Support (initial) (#6426)

#### Summary
Fixes #3117

Additionally it adds support for UTF-8 in URL parser (as it should).
Label sizes now are updated by browser with JavaScript (although guess is still calculated by verdana11_widths with minor improvements)

#### Component Name
API/Badges, LibNetData/URL

#### Additional Information
It was found that not only verdana11_widths need to be updated but the url parser replaces international characters with spaces (one space per each byte of multibyte character).
Therefore I update both to support international chars.

8 files changed, 226 insertions, 164 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6bfab928ff..4d631f2fe7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -320,6 +320,7 @@ set(LIBNETDATA_FILES
         libnetdata/json/jsmn.h
         libnetdata/health/health.c
         libnetdata/health/health.h
+        libnetdata/string/utf8.h
         libnetdata/socket/security.c
         libnetdata/socket/security.h)
 
diff --git a/Makefile.am b/Makefile.am
index bc928bba87..de161c849d 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -167,6 +167,7 @@ LIBNETDATA_FILES = \
 	libnetdata/json/jsmn.h \
 	libnetdata/health/health.c \
 	libnetdata/health/health.h \
+    libnetdata/string/utf8.h \
     $(NULL)
 
 APPS_PLUGIN_FILES = \
diff --git a/libnetdata/libnetdata.h b/libnetdata/libnetdata.h
index 1672ae3004..ef883300b8 100644
--- a/libnetdata/libnetdata.h
+++ b/libnetdata/libnetdata.h
@@ -313,5 +313,6 @@ extern char *netdata_configured_host_prefix;
 #include "url/url.h"
 #include "json/json.h"
 #include "health/health.h"
+#include "string/utf8.h"
 
 #endif // NETDATA_LIB_H
diff --git a/libnetdata/string/utf8.h b/libnetdata/string/utf8.h
new file mode 100644
index 0000000000..133ec710b6
--- /dev/null
+++ b/libnetdata/string/utf8.h
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef NETDATA_STRING_UTF8_H
+#define NETDATA_STRING_UTF8_H 1
+
+#define IS_UTF8_BYTE(x) (x & 0x80)
+#define IS_UTF8_STARTBYTE(x) (IS_UTF8_BYTE(x)&&(x & 0x40))
+
+#endif /* NETDATA_STRING_UTF8_H */
diff --git a/libnetdata/url/url.c b/libnetdata/url/url.c
index 07a9f8069e..1929d6686f 100644
--- a/libnetdata/url/url.c
+++ b/libnetdata/url/url.c
@@ -52,6 +52,125 @@ char *url_decode(char *str) {
     return url_decode_r(buf, str, size);
 }
 
+//decode %XX character or return 0 if cannot
+char url_percent_escape_decode(char *s) {
+    if(likely(s[1] && s[2]))
+        return from_hex(s[1]) << 4 | from_hex(s[2]);
+    return 0;
+}
+
+//this (utf8 string related) should be moved in separate file in future
+char url_utf8_get_byte_length(char c) {
+    if(!IS_UTF8_BYTE(c))
+        return 1;
+
+    char length = 0;
+    while(likely(c & 0x80)) {
+        length++;
+        c <<= 1;
+    }
+    //4 byte is max size for UTF-8 char
+    //10XX XXXX is not valid character -> check length == 1
+    if(length > 4 || length == 1)
+        return -1;
+
+    return length;
+}
+
+//decode % encoded UTF-8 characters and copy them to *d
+//return count of bytes written to *d
+char url_decode_multibyte_utf8(char *s, char *d, char *d_end) {
+    char first_byte = url_percent_escape_decode(s);
+
+    if(unlikely(!first_byte || !IS_UTF8_STARTBYTE(first_byte)))
+        return 0;
+
+    char byte_length = url_utf8_get_byte_length(first_byte);
+
+    if(unlikely(byte_length <= 0 || d+byte_length >= d_end))
+        return 0;
+
+    char to_read = byte_length;
+    while(to_read > 0) {
+        char c = url_percent_escape_decode(s);
+
+        if(unlikely( !IS_UTF8_BYTE(c) ))
+            return 0;
+        if((to_read != byte_length) && IS_UTF8_STARTBYTE(c)) 
+            return 0;
+
+        *d++ = c;
+        s+=3;
+        to_read--;
+    }
+
+    return byte_length;
+}
+
+/*
+ * The utf8_check() function scans the '\0'-terminated string starting
+ * at s. It returns a pointer to the first byte of the first malformed
+ * or overlong UTF-8 sequence found, or NULL if the string contains
+ * only correct UTF-8. It also spots UTF-8 sequences that could cause
+ * trouble if converted to UTF-16, namely surrogate characters
+ * (U+D800..U+DFFF) and non-Unicode positions (U+FFFE..U+FFFF). This
+ * routine is very likely to find a malformed sequence if the input
+ * uses any other encoding than UTF-8. It therefore can be used as a
+ * very effective heuristic for distinguishing between UTF-8 and other
+ * encodings.
+ *
+ * Markus Kuhn <http://www.cl.cam.ac.uk/~mgk25/> -- 2005-03-30
+ * License: http://www.cl.cam.ac.uk/~mgk25/short-license.html
+ */
+
+unsigned char *utf8_check(unsigned char *s)
+{
+    while (*s)
+    {
+        if (*s < 0x80)
+            /* 0xxxxxxx */
+            s++;
+        else if ((s[0] & 0xe0) == 0xc0)
+        {
+            /* 110XXXXx 10xxxxxx */
+            if ((s[1] & 0xc0) != 0x80 ||
+                (s[0] & 0xfe) == 0xc0) /* overlong? */
+                return s;
+            else
+                s += 2;
+        }
+        else if ((s[0] & 0xf0) == 0xe0)
+        {
+            /* 1110XXXX 10Xxxxxx 10xxxxxx */
+            if ((s[1] & 0xc0) != 0x80 ||
+                (s[2] & 0xc0) != 0x80 ||
+                (s[0] == 0xe0 && (s[1] & 0xe0) == 0x80) || /* overlong? */
+                (s[0] == 0xed && (s[1] & 0xe0) == 0xa0) || /* surrogate? */
+                (s[0] == 0xef && s[1] == 0xbf &&
+                 (s[2] & 0xfe) == 0xbe)) /* U+FFFE or U+FFFF? */
+                return s;
+            else
+                s += 3;
+        }
+        else if ((s[0] & 0xf8) == 0xf0)
+        {
+            /* 11110XXX 10XXxxxx 10xxxxxx 10xxxxxx */
+            if ((s[1] & 0xc0) != 0x80 ||
+                (s[2] & 0xc0) != 0x80 ||
+                (s[3] & 0xc0) != 0x80 ||
+                (s[0] == 0xf0 && (s[1] & 0xf0) == 0x80) ||    /* overlong? */
+                (s[0] == 0xf4 && s[1] > 0x8f) || s[0] > 0xf4) /* > U+10FFFF? */
+                return s;
+            else
+                s += 4;
+        }
+        else
+            return s;
+    }
+
+    return NULL;
+}
+
 char *url_decode_r(char *to, char *url, size_t size) {
     char *s = url,           // source
          *d = to,            // destination
@@ -59,12 +178,24 @@ char *url_decode_r(char *to, char *url, size_t size) {
 
     while(*s && d < e) {
         if(unlikely(*s == '%')) {
-            if(likely(s[1] && s[2])) {
-                char t = from_hex(s[1]) << 4 | from_hex(s[2]);
+            char t = url_percent_escape_decode(s);
+            if(IS_UTF8_BYTE(t)) {
+                char bytes_written = url_decode_multibyte_utf8(s, d, e);
+                if(likely(bytes_written)){
+                    d += bytes_written;
+                    s += (bytes_written * 3)-1;
+                }
+                else {
+                    goto fail_cleanup;
+                }
+            }
+            else if(likely(t) && isprint(t)) {
                 // avoid HTTP header injection
-                *d++ = (char)((isprint(t))? t : ' ');
+                *d++ = t;
                 s += 2;
             }
+            else
+                goto fail_cleanup;
         }
         else if(unlikely(*s == '+'))
             *d++ = ' ';
@@ -77,5 +208,12 @@ char *url_decode_r(char *to, char *url, size_t size) {
 
     *d = '\0';
 
+    if(unlikely( utf8_check(to) )) //NULL means sucess here
+        return NULL;
+
     return to;
+
+fail_cleanup:
+    *d = '\0';
+    return NULL;
 }
diff --git a/web/api/badges/web_buffer_svg.c b/web/api/badges/web_buffer_svg.c
index b24fddedf5..4f9826fb20 100644
--- a/web/api/badges/web_buffer_svg.c
+++ b/web/api/badges/web_buffer_svg.c
@@ -11,7 +11,7 @@
  * https://github.com/badges/shields/blob/master/measure-text.js
 */
 
-static double verdana11_widths[256] = {
+static double verdana11_widths[128] = {
     [0] = 0.0,
     [1] = 0.0,
     [2] = 0.0,
@@ -139,157 +139,36 @@ static double verdana11_widths[256] = {
     [124] = 4.9951171875, // |
     [125] = 6.982421875, // }
     [126] = 9.001953125, // ~
-    [127] = 0.0,
-    [128] = 0.0,
-    [129] = 0.0,
-    [130] = 0.0,
-    [131] = 0.0,
-    [132] = 0.0,
-    [133] = 0.0,
-    [134] = 0.0,
-    [135] = 0.0,
-    [136] = 0.0,
-    [137] = 0.0,
-    [138] = 0.0,
-    [139] = 0.0,
-    [140] = 0.0,
-    [141] = 0.0,
-    [142] = 0.0,
-    [143] = 0.0,
-    [144] = 0.0,
-    [145] = 0.0,
-    [146] = 0.0,
-    [147] = 0.0,
-    [148] = 0.0,
-    [149] = 0.0,
-    [150] = 0.0,
-    [151] = 0.0,
-    [152] = 0.0,
-    [153] = 0.0,
-    [154] = 0.0,
-    [155] = 0.0,
-    [156] = 0.0,
-    [157] = 0.0,
-    [158] = 0.0,
-    [159] = 0.0,
-    [160] = 0.0,
-    [161] = 0.0,
-    [162] = 0.0,
-    [163] = 0.0,
-    [164] = 0.0,
-    [165] = 0.0,
-    [166] = 0.0,
-    [167] = 0.0,
-    [168] = 0.0,
-    [169] = 0.0,
-    [170] = 0.0,
-    [171] = 0.0,
-    [172] = 0.0,
-    [173] = 0.0,
-    [174] = 0.0,
-    [175] = 0.0,
-    [176] = 0.0,
-    [177] = 0.0,
-    [178] = 0.0,
-    [179] = 0.0,
-    [180] = 0.0,
-    [181] = 0.0,
-    [182] = 0.0,
-    [183] = 0.0,
-    [184] = 0.0,
-    [185] = 0.0,
-    [186] = 0.0,
-    [187] = 0.0,
-    [188] = 0.0,
-    [189] = 0.0,
-    [190] = 0.0,
-    [191] = 0.0,
-    [192] = 0.0,
-    [193] = 0.0,
-    [194] = 0.0,
-    [195] = 0.0,
-    [196] = 0.0,
-    [197] = 0.0,
-    [198] = 0.0,
-    [199] = 0.0,
-    [200] = 0.0,
-    [201] = 0.0,
-    [202] = 0.0,
-    [203] = 0.0,
-    [204] = 0.0,
-    [205] = 0.0,
-    [206] = 0.0,
-    [207] = 0.0,
-    [208] = 0.0,
-    [209] = 0.0,
-    [210] = 0.0,
-    [211] = 0.0,
-    [212] = 0.0,
-    [213] = 0.0,
-    [214] = 0.0,
-    [215] = 0.0,
-    [216] = 0.0,
-    [217] = 0.0,
-    [218] = 0.0,
-    [219] = 0.0,
-    [220] = 0.0,
-    [221] = 0.0,
-    [222] = 0.0,
-    [223] = 0.0,
-    [224] = 0.0,
-    [225] = 0.0,
-    [226] = 0.0,
-    [227] = 0.0,
-    [228] = 0.0,
-    [229] = 0.0,
-    [230] = 0.0,
-    [231] = 0.0,
-    [232] = 0.0,
-    [233] = 0.0,
-    [234] = 0.0,
-    [235] = 0.0,
-    [236] = 0.0,
-    [237] = 0.0,
-    [238] = 0.0,
-    [239] = 0.0,
-    [240] = 0.0,
-    [241] = 0.0,
-    [242] = 0.0,
-    [243] = 0.0,
-    [244] = 0.0,
-    [245] = 0.0,
-    [246] = 0.0,
-    [247] = 0.0,
-    [248] = 0.0,
-    [249] = 0.0,
-    [250] = 0.0,
-    [251] = 0.0,
-    [252] = 0.0,
-    [253] = 0.0,
-    [254] = 0.0,
-    [255] = 0.0
+    [127] = 0.0
 };
 
 // find the width of the string using the verdana 11points font
-// re-write the string in place, skiping zero-length characters
-static inline double verdana11_width(char *s) {
+static inline double verdana11_width(const char *s, float em_size) {
     double w = 0.0;
-    char *d = s;
 
     while(*s) {
-        double t = verdana11_widths[(unsigned char)*s];
-        if(t == 0.0)
+        // if UTF8 multibyte char found and guess it's width equal 1em
+        // as label width will be updated with JavaScript this is not so important
+
+        // TODO: maybe move UTF8 functions from url.c to separate util in libnetdata
+        //       then use url_utf8_get_byte_length etc.
+        if(IS_UTF8_STARTBYTE(*s)) {
             s++;
+            while(IS_UTF8_BYTE(*s) && !IS_UTF8_STARTBYTE(*s)){
+                s++;
+            }
+            w += em_size;
+        }
         else {
-            w += t + VERDANA_KERNING;
-            if(d != s)
-                *d++ = *s++;
-            else
-                d = ++s;
+            if(likely(!(*s & 0x80))){ // Byte 1XXX XXXX is not valid in UTF8
+            double t = verdana11_widths[(unsigned char)*s];
+                if(t != 0.0)
+                w += t + VERDANA_KERNING;
+            }
+            s++;
         }
     }
 
-    *d = '\0';
     w -= VERDANA_KERNING;
     w += VERDANA_PADDING;
     return w;
@@ -810,8 +689,7 @@ static inline void calc_colorz(const char *color, char *final, size_t len, calcu
 #define COLOR_STRING_SIZE 100
 
 void buffer_svg(BUFFER *wb, const char *label, calculated_number value, const char *units, const char *label_color, const char *value_color, int precision, int scale, uint32_t options) {
-    char      label_buffer[LABEL_STRING_SIZE + 1]
-            , value_color_buffer[COLOR_STRING_SIZE + 1]
+    char    value_color_buffer[COLOR_STRING_SIZE + 1]
             , value_string[VALUE_STRING_SIZE + 1]
             , label_escaped[LABEL_STRING_SIZE + 1]
             , value_escaped[VALUE_STRING_SIZE + 1]
@@ -831,14 +709,11 @@ void buffer_svg(BUFFER *wb, const char *label, calculated_number value, const ch
     calc_colorz(value_color, value_color_buffer, COLOR_STRING_SIZE, value);
     format_value_and_unit(value_string, VALUE_STRING_SIZE, (options & RRDR_OPTION_DISPLAY_ABS)?calculated_number_fabs(value):value, units, precision);
 
-    // we need to copy the label, since verdana11_width may write to it
-    strncpyz(label_buffer, label, LABEL_STRING_SIZE);
-
-    label_width = verdana11_width(label_buffer) + (BADGE_HORIZONTAL_PADDING * 2);
-    value_width = verdana11_width(value_string) + (BADGE_HORIZONTAL_PADDING * 2);
+    label_width = verdana11_width(label, font_size) + (BADGE_HORIZONTAL_PADDING * 2);
+    value_width = verdana11_width(value_string, font_size) + (BADGE_HORIZONTAL_PADDING * 2);
     total_width = label_width + value_width;
 
-    escape_xmlz(label_escaped, label_buffer, LABEL_STRING_SIZE);
+    escape_xmlz(label_escaped, label, LABEL_STRING_SIZE);
     escape_xmlz(value_escaped, value_string, VALUE_STRING_SIZE);
     escape_xmlz(label_color_escaped, color_map(label_color), COLOR_STRING_SIZE);
     escape_xmlz(value_color_escaped, color_map(value_color_buffer), COLOR_STRING_SIZE);
@@ -862,19 +737,43 @@ void buffer_svg(BUFFER *wb, const char *label, calculated_number value, const ch
                 "<stop offset=\"1\" stop-opacity=\".1\"/>"
             "</linearGradient>"
             "<mask id=\"round\">"
-                "<rect width=\"%0.2f\" height=\"%0.2f\" rx=\"%0.2f\" fill=\"#fff\"/>"
+                "<rect class=\"bdge-ttl-width\" width=\"%0.2f\" height=\"%0.2f\" rx=\"%0.2f\" fill=\"#fff\"/>"
             "</mask>"
             "<g mask=\"url(#round)\">"
-                "<rect width=\"%0.2f\" height=\"%0.2f\" fill=\"%s\"/>"
-                "<rect x=\"%0.2f\" width=\"%0.2f\" height=\"%0.2f\" fill=\"%s\"/>"
-                "<rect width=\"%0.2f\" height=\"%0.2f\" fill=\"url(#smooth)\"/>"
+                "<rect class=\"bdge-rect-lbl\" width=\"%0.2f\" height=\"%0.2f\" fill=\"%s\"/>"
+                "<rect class=\"bdge-rect-val\" x=\"%0.2f\" width=\"%0.2f\" height=\"%0.2f\" fill=\"%s\"/>"
+                "<rect class=\"bdge-ttl-width\" width=\"%0.2f\" height=\"%0.2f\" fill=\"url(#smooth)\"/>"
             "</g>"
             "<g fill=\"#fff\" text-anchor=\"middle\" font-family=\"DejaVu Sans,Verdana,Geneva,sans-serif\" font-size=\"%0.2f\">"
-                "<text x=\"%0.2f\" y=\"%0.0f\" fill=\"#010101\" fill-opacity=\".3\">%s</text>"
-                "<text x=\"%0.2f\" y=\"%0.0f\">%s</text>"
-                "<text x=\"%0.2f\" y=\"%0.0f\" fill=\"#010101\" fill-opacity=\".3\">%s</text>"
-                "<text x=\"%0.2f\" y=\"%0.0f\">%s</text>"
+                "<text class=\"bdge-lbl-lbl\" x=\"%0.2f\" y=\"%0.0f\" fill=\"#010101\" fill-opacity=\".3\">%s</text>"
+                "<text class=\"bdge-lbl-lbl\" x=\"%0.2f\" y=\"%0.0f\">%s</text>"
+                "<text class=\"bdge-lbl-val\" x=\"%0.2f\" y=\"%0.0f\" fill=\"#010101\" fill-opacity=\".3\">%s</text>"
+                "<text class=\"bdge-lbl-val\" x=\"%0.2f\" y=\"%0.0f\">%s</text>"
             "</g>"
+            "<script type=\"text/javascript\">"
+                "var bdg_horiz_padding = %d;"
+                "function netdata_bdge_each(list, attr, value){"
+                    "Array.prototype.forEach.call(list, function(el){"
+                        "el.setAttribute(attr, value);"
+                    "});"
+                "};"
+                "var this_svg = document.currentScript.closest(\"svg\");"
+                "var elem_lbl = this_svg.getElementsByClassName(\"bdge-lbl-lbl\");"
+                "var elem_val = this_svg.getElementsByClassName(\"bdge-lbl-val\");"
+                "var lbl_size = elem_lbl[0].getBBox();"
+                "var val_size = elem_val[0].getBBox();"
+                "var width_total = lbl_size.width + bdg_horiz_padding*2;"
+                "this_svg.getElementsByClassName(\"bdge-rect-lbl\")[0].setAttribute(\"width\", width_total);"
+                "netdata_bdge_each(elem_lbl, \"x\", (lbl_size.width / 2) + bdg_horiz_padding);"
+                "netdata_bdge_each(elem_val, \"x\", width_total + (val_size.width / 2) + bdg_horiz_padding);"
+                "var val_rect = this_svg.getElementsByClassName(\"bdge-rect-val\")[0];"
+                "val_rect.setAttribute(\"width\", val_size.width + bdg_horiz_padding*2);"
+                "val_rect.setAttribute(\"x\", width_total);"
+                "width_total += val_size.width + bdg_horiz_padding*2;"
+                "var width_update_elems = this_svg.getElementsByClassName(\"bdge-ttl-width\");"
+                "netdata_bdge_each(width_update_elems, \"width\", width_total);"
+                "this_svg.setAttribute(\"width\", width_total);"
+            "</script>"
         "</svg>",
         total_width, height,
         total_width, height, round_corner,
@@ -885,7 +784,8 @@ void buffer_svg(BUFFER *wb, const char *label, calculated_number value, const ch
         label_width / 2, ceil(height - text_offset), label_escaped,
         label_width / 2, ceil(height - text_offset - 1.0), label_escaped,
         label_width + value_width / 2 -1, ceil(height - text_offset), value_escaped,
-        label_width + value_width / 2 -1, ceil(height - text_offset - 1.0), value_escaped);
+        label_width + value_width / 2 -1, ceil(height - text_offset - 1.0), value_escaped,
+        BADGE_HORIZONTAL_PADDING );
 }
 
 int web_client_api_request_v1_badge(RRDHOST *host, struct web_client *w, char *url) {
diff --git a/web/server/web_client.c b/web/server/web_client.c
index bd275f5e50..20745d8dd4 100644
--- a/web/server/web_client.c
+++ b/web/server/web_client.c
@@ -821,6 +821,7 @@ static inline char *http_header_parse(struct web_client *w, char *s, int parse_u
 typedef enum {
     HTTP_VALIDATION_OK,
     HTTP_VALIDATION_NOT_SUPPORTED,
+    HTTP_VALIDATION_MALFORMED_URL,
 #ifdef ENABLE_HTTPS
     HTTP_VALIDATION_INCOMPLETE,
     HTTP_VALIDATION_REDIRECT
@@ -941,7 +942,8 @@ static inline HTTP_VALIDATION http_request_validate(struct web_client *w) {
                 // a valid complete HTTP request found
 
                 *ue = '\0';
-                url_decode_r(w->decoded_url, encoded_url, NETDATA_WEB_REQUEST_URL_SIZE + 1);
+                if(!url_decode_r(w->decoded_url, encoded_url, NETDATA_WEB_REQUEST_URL_SIZE + 1))
+                    return HTTP_VALIDATION_MALFORMED_URL;
                 *ue = ' ';
                 
                 // copy the URL - we are going to overwrite parts of it
@@ -1424,7 +1426,7 @@ void web_client_process_request(struct web_client *w) {
 
                 buffer_flush(w->response.data);
                 buffer_sprintf(w->response.data, "Received request is too big  (%zu bytes).\r\n", w->response.data->len);
-                w->response.code = 400;
+                w->response.code = HTTP_RESPONSE_BAD_REQUEST;
             }
             else {
                 // wait for more data
@@ -1441,12 +1443,19 @@ void web_client_process_request(struct web_client *w) {
             break;
         }
 #endif
+        case HTTP_VALIDATION_MALFORMED_URL:
+            debug(D_WEB_CLIENT_ACCESS, "%llu: URL parsing failed (malformed URL). Cannot understand '%s'.", w->id, w->response.data->buffer);
+
+            buffer_flush(w->response.data);
+            buffer_strcat(w->response.data, "URL not valid. I don't understand you...\r\n");
+            w->response.code = HTTP_RESPONSE_BAD_REQUEST;
+            break;
         case HTTP_VALIDATION_NOT_SUPPORTED:
             debug(D_WEB_CLIENT_ACCESS, "%llu: Cannot understand '%s'.", w->id, w->response.data->buffer);
 
             buffer_flush(w->response.data);
             buffer_strcat(w->response.data, "I don't understand you...\r\n");
-            w->response.code = 400;
+            w->response.code = HTTP_RESPONSE_BAD_REQUEST;
             break;
     }
 
diff --git a/web/server/web_client.h b/web/server/web_client.h
index 0a57e8d8e7..c6de66979e 100644
--- a/web/server/web_client.h
+++ b/web/server/web_client.h
@@ -11,6 +11,9 @@ extern int web_enable_gzip,
         web_gzip_strategy;
 #endif /* NETDATA_WITH_ZLIB */
 
+//HTTP_CODES 4XX
+#define HTTP_RESPONSE_BAD_REQUEST   400
+
 extern int respect_web_browser_do_not_track_policy;
 extern char *web_x_frame_options;