Added utils library initialization function and improved replace_quoted

Currently the initialization function only prepares PCRE2 patterns for use.
Added the call to the new utils_init() function to MaxScale and all relevant
tests.

The replace_quoted now uses a shared PCRE2 pattern which should remove some
of the overhead of the function.

server/core/gateway.c

@@ -1574,6 +1574,14 @@ int main(int argc, char **argv)
         goto return_main;
     }
 
+    if (!utils_init())
+    {
+        char* logerr = "Failed to initialise utility library.";
+        print_log_n_stderr(true, true, logerr, logerr, eno);
+        rc = MAXSCALE_INTERNALERROR;
+        goto return_main;
+    }
+
     /** OpenSSL initialization */
     if (!HAVE_OPENSSL_THREADS)
     {
@@ -1939,6 +1947,7 @@ int main(int argc, char **argv)
     /** Release mysql thread context*/
     mysql_thread_end();
 
+    utils_end();
     datadir_cleanup();
     MXS_NOTICE("MaxScale shutdown completed.");
 

utils/skygw_utils.cc

@@ -2122,6 +2122,9 @@ retblock:
         return newstr;
 }
 
+static pcre2_code* replace_quoted_re = NULL;
+static const PCRE2_SPTR replace_quoted_pattern = (PCRE2_SPTR) "(['\"])[^'\"]+(['\"])";
+
 /**
  * Replace everything inside single or double quotes with question marks.
  * @param str String to modify
@@ -2129,52 +2132,35 @@ retblock:
  */
 char* replace_quoted(const char* str)
 {
-    PCRE2_SIZE erroffset;
-    int errcore;
-    static const PCRE2_SPTR pattern = (PCRE2_SPTR) "(['\"])[^'\"]+(['\"])";
     static const PCRE2_SPTR replace = (PCRE2_SPTR) "$1?$2";
-    pcre2_code* re;
     pcre2_match_data* mdata;
-    int orig_len = strlen(str);
-    size_t len = strlen(str);
+    size_t orig_len = strlen(str);
+    size_t len = orig_len;
     char* output;
 
-    if ((output = (char*) malloc(len * sizeof(char))))
+    if ((output = (char*) malloc(len * sizeof (char))) &&
+        (mdata = pcre2_match_data_create_from_pattern(replace_quoted_re, NULL)))
     {
-         /** TODO: Consider moving pattern compilation to some init function. */
-        if ((re = pcre2_compile(pattern, PCRE2_ZERO_TERMINATED,
-                                0, &errcore, &erroffset, NULL)))
+        while (pcre2_substitute(replace_quoted_re, (PCRE2_SPTR) str, orig_len, 0,
+                                PCRE2_SUBSTITUTE_GLOBAL, mdata, NULL,
+                                replace, PCRE2_ZERO_TERMINATED,
+                                (PCRE2_UCHAR8*) output, &len) == PCRE2_ERROR_NOMEMORY)
         {
-            if ((mdata = pcre2_match_data_create_from_pattern(re, NULL)))
-            {
-                while (pcre2_substitute(re, (PCRE2_SPTR) str, orig_len, 0,
-                                        PCRE2_SUBSTITUTE_GLOBAL, mdata, NULL,
-                                        replace, PCRE2_ZERO_TERMINATED,
-                                        (PCRE2_UCHAR8*) output, &len) == PCRE2_ERROR_NOMEMORY)
-                {
-                    char* tmp = (char*) realloc(output, len *= 2);
-                    if (tmp == NULL)
-                    {
-                        free(output);
-                        output = NULL;
-                        break;
-                    }
-                    output = tmp;
-                }
-                pcre2_match_data_free(mdata);
-            }
-            else
+            char* tmp = (char*) realloc(output, len *= 2);
+            if (tmp == NULL)
             {
                 free(output);
                 output = NULL;
+                break;
             }
-            pcre2_code_free(re);
-        }
-        else
-        {
-            free(output);
-            output = NULL;
+            output = tmp;
         }
+        pcre2_match_data_free(mdata);
+    }
+    else
+    {
+        free(output);
+        output = NULL;
     }
     return output;
 }
@@ -2267,3 +2253,36 @@ int simple_str_hash(char* key)
 
   return hash;
 }
+
+/**
+ * Initialize the utils library
+ *
+ * This function initializes structures used in various functions.
+ * @return true on success, false on error
+ */
+bool utils_init()
+{
+    bool rval = true;
+
+    PCRE2_SIZE erroffset;
+    int errcore;
+
+    ss_info_dassert(replace_quoted_re == NULL, "utils_init called multiple times");
+    replace_quoted_re = pcre2_compile(replace_quoted_pattern, PCRE2_ZERO_TERMINATED, 0, &errcore,
+                                      &erroffset, NULL);
+    if (replace_quoted_re == NULL)
+    {
+        rval = false;
+    }
+
+    return rval;
+}
+
+/**
+ * Close the utils library. This should be the last call to this library.
+ */
+void utils_end()
+{
+    pcre2_code_free(replace_quoted_re);
+    replace_quoted_re = NULL;
+}

utils/skygw_utils.h

@@ -158,6 +158,8 @@ struct skygw_file_st {
 
 EXTERN_C_BLOCK_BEGIN
 
+bool utils_init(); /*< Call this first before using any other function */
+void utils_end();
 slist_cursor_t* slist_init(void);
 void slist_done(slist_cursor_t* c);
 size_t slist_size(slist_cursor_t* c);