[Feature] Improve lua binary strings output

diff --git a/src/lua/lua_logger.c b/src/lua/lua_logger.c
index 20b59efa7de89755672ae863b3028c42cfb37a65..67b70eaad0ecb21cd4896364913e161d71a54674 100644 (file)
--- a/src/lua/lua_logger.c
+++ b/src/lua/lua_logger.c
@@ -273,12 +273,57 @@ static gsize
 lua_logger_out_str (lua_State *L, gint pos, gchar *outbuf, gsize len,
                                        struct lua_logger_trace *trace)
 {
-       gsize slen;
+       gsize slen, flen;
        const gchar *str = lua_tolstring (L, pos, &slen);
-       gsize r = 0;
+       static const gchar hexdigests[16] = "0123456789abcdef";
+       gsize r = 0, s;
 
        if (str) {
-               r = rspamd_strlcpy (outbuf, str, MIN (slen, len) + 1);
+               gboolean normal = TRUE;
+               flen = MIN (slen, len - 1);
+
+               for (r = 0; r < flen; r ++) {
+                       if (!(g_ascii_isprint (str[r]) || (str[r] & 0x80))) {
+                               normal = FALSE;
+                               break;
+                       }
+               }
+
+               if (normal) {
+                       r = rspamd_strlcpy (outbuf, str, flen + 1);
+               }
+               else {
+                       /* Need to escape non printed characters */
+                       r = 0;
+                       s = 0;
+
+                       while (slen > 0 && len > 1) {
+                               if (!g_ascii_isprint (str[s])) {
+                                       if (str[s] & 0x80) {
+                                               outbuf[r++] = str[s];
+                                       }
+                                       else if (len >= 3) {
+                                               outbuf[r++] = '\\';
+                                               outbuf[r++] = hexdigests[((str[s] >> 4) & 0xF)];
+                                               outbuf[r++] = hexdigests[((str[s]) & 0xF)];
+
+                                               len -= 2;
+                                       }
+                                       else {
+                                               outbuf[r++] = '?';
+                                       }
+                               }
+                               else {
+                                       outbuf[r++] = str[s];
+                               }
+
+                               s++;
+                               slen --;
+                               len --;
+                       }
+
+                       outbuf[r] = '\0';
+               }
        }
 
        return r;