How Mysql Connection Error to user

fixes #207

includes/mysqli_provider.php

@@ -5,7 +5,7 @@
  */
 function sql_close() {
   global $sql_connection;
-  
+
   return $sql_connection->close();
 }
 
@@ -21,7 +21,7 @@ function sql_null($value = null) {
  */
 function sql_transaction_start() {
   global $sql_nested_transaction_level;
-  
+
   if ($sql_nested_transaction_level ++ == 0)
     return sql_query("BEGIN");
   else
@@ -33,7 +33,7 @@ function sql_transaction_start() {
  */
 function sql_transaction_commit() {
   global $sql_nested_transaction_level;
-  
+
   if (-- $sql_nested_transaction_level == 0)
     return sql_query("COMMIT");
   else
@@ -45,7 +45,7 @@ function sql_transaction_commit() {
  */
 function sql_transaction_rollback() {
   global $sql_nested_transaction_level;
-  
+
   if (-- $sql_nested_transaction_level == 0)
     return sql_query("ROLLBACK");
   else
@@ -55,17 +55,17 @@ function sql_transaction_rollback() {
 /**
  * Logs an sql error.
  *
- * @param string $message          
+ * @param string $message
  * @return false
  */
 function sql_error($message) {
   sql_close();
-  
+
   $message = trim($message) . "\n";
   $message .= debug_string_backtrace() . "\n";
-  
+
   error_log('mysql_provider error: ' . $message);
-  
+
   return false;
 }
 
@@ -84,19 +84,21 @@ function sql_error($message) {
  */
 function sql_connect($host, $user, $pass, $db) {
   global $sql_connection;
-  
+
   $sql_connection = new mysqli($host, $user, $pass, $db);
-  if ($sql_connection->connect_errno)
+  if ($sql_connection->connect_errno) {
+      error("Unable to connect to MySQL: " . $sql_connection->connect_error);
     return sql_error("Unable to connect to MySQL: " . $sql_connection->connect_error);
-  
+  }
+
   $result = $sql_connection->query("SET CHARACTER SET utf8;");
   if (! $result)
     return sql_error("Unable to set utf8 character set (" . $sql_connection->errno . ") " . $sql_connection->error);
-  
+
   $result = $sql_connection->set_charset('utf8');
   if (! $result)
     return sql_error("Unable to set utf8 names (" . $sql_connection->errno . ") " . $sql_connection->error);
-  
+
   return $sql_connection;
 }
 
@@ -117,12 +119,12 @@ function sql_select_db($db_name) {
 /**
  * MySQL SELECT query
  *
- * @param string $query          
+ * @param string $query
  * @return Result array or false on error
  */
 function sql_select($query) {
   global $sql_connection;
-  
+
   $result = $sql_connection->query($query);
   if ($result) {
     $data = array();
@@ -136,12 +138,12 @@ function sql_select($query) {
 /**
  * MySQL execute a query
  *
- * @param string $query          
+ * @param string $query
  * @return mysqli_result boolean resource or false on error
  */
 function sql_query($query) {
   global $sql_connection;
-  
+
   $result = $sql_connection->query($query);
   if ($result) {
     return $result;
@@ -162,7 +164,7 @@ function sql_id() {
 /**
  * Escape a string for a sql query.
  *
- * @param string $query          
+ * @param string $query
  * @return string
  */
 function sql_escape($query) {
@@ -172,8 +174,8 @@ function sql_escape($query) {
 
 /**
  * Convert a boolean for mysql-queries.
- * 
- * @param boolean $boolean          
+ *
+ * @param boolean $boolean
  * @return string
  */
 function sql_bool($boolean) {
@@ -183,7 +185,7 @@ function sql_bool($boolean) {
 /**
  * Count query result lines.
  *
- * @param string $query          
+ * @param string $query
  * @return int Count of result lines
  */
 function sql_num_query($query) {