1 files changed, 74 insertions, 27 deletions

diff --git a/sql/protocol.cc b/sql/protocol.cc
index 9242b348f0b..a0e14423b73 100644
--- a/sql/protocol.cc
+++ b/sql/protocol.cc
@@ -1,4 +1,4 @@
-/* Copyright (c) 2000, 2010 Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2000, 2010 Oracle and/or its affiliates.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -58,6 +58,65 @@ bool Protocol_binary::net_store_data(const uchar *from, size_t length)
 }
 
 
+/*
+  net_store_data() - extended version with character set conversion.
+  
+  It is optimized for short strings whose length after
+  conversion is garanteed to be less than 251, which accupies
+  exactly one byte to store length. It allows not to use
+  the "convert" member as a temporary buffer, conversion
+  is done directly to the "packet" member.
+  The limit 251 is good enough to optimize send_fields()
+  because column, table, database names fit into this limit.
+*/
+
+#ifndef EMBEDDED_LIBRARY
+bool Protocol::net_store_data(const uchar *from, size_t length,
+                              CHARSET_INFO *from_cs, CHARSET_INFO *to_cs)
+{
+  uint dummy_errors;
+  /* Calculate maxumum possible result length */
+  size_t conv_length= to_cs->mbmaxlen * length / from_cs->mbminlen;
+  ulong packet_length, new_length;
+  char *length_pos, *to;
+
+  if (conv_length > 250)
+  {
+    /*
+      For strings with conv_length greater than 250 bytes
+      we don't know how many bytes we will need to store length: one or two,
+      because we don't know result length until conversion is done.
+      For example, when converting from utf8 (mbmaxlen=3) to latin1,
+      conv_length=300 means that the result length can vary between 100 to 300.
+      length=100 needs one byte, length=300 needs to bytes.
+      
+      Thus conversion directly to "packet" is not worthy.
+      Let's use "convert" as a temporary buffer.
+    */
+    return (convert->copy((const char*) from, length, from_cs, to_cs,
+                          &dummy_errors) ||
+            net_store_data((const uchar*) convert->ptr(), convert->length()));
+  }
+
+  packet_length= packet->length();
+  new_length= packet_length + conv_length + 1;
+
+  if (new_length > packet->alloced_length() && packet->realloc(new_length))
+    return 1;
+
+  length_pos= (char*) packet->ptr() + packet_length;
+  to= length_pos + 1;
+
+  to+= copy_and_convert(to, conv_length, to_cs,
+                        (const char*) from, length, from_cs, &dummy_errors);
+
+  net_store_length((uchar*) length_pos, to - length_pos - 1);
+  packet->length((uint) (to - packet->ptr()));
+  return 0;
+}
+#endif
+
+
 /**
   Send a error string to client.
 
@@ -144,7 +203,7 @@ net_send_ok(THD *thd,
   NET *net= &thd->net;
   uchar buff[MYSQL_ERRMSG_SIZE+10],*pos;
   bool error= FALSE;
-  DBUG_ENTER("my_ok");
+  DBUG_ENTER("net_send_ok");
 
   if (! net->vio)	// hack for re-parsing queries
   {
@@ -282,24 +341,6 @@ static bool write_eof_packet(THD *thd, NET *net,
 }
 
 /**
-  Please client to send scrambled_password in old format.
-     
-  @param thd thread handle
-
-  @retval
-    0  ok
-  @retval
-   !0  error
-*/
-
-bool send_old_password_request(THD *thd)
-{
-  NET *net= &thd->net;
-  return my_net_write(net, eof_buff, 1) || net_flush(net);
-}
-
-
-/**
   @param thd Thread handler
   @param sql_errno The error code to send
   @param err A pointer to the error message
@@ -430,6 +471,7 @@ static uchar *net_store_length_fast(uchar *packet, uint length)
 
 void net_end_statement(THD *thd)
 {
+  DBUG_ENTER("net_end_statement");
   DBUG_ASSERT(! thd->main_da.is_sent);
 
   /* Can not be true, but do not take chances in production. */
@@ -469,6 +511,7 @@ void net_end_statement(THD *thd)
   }
   if (!error)
     thd->main_da.is_sent= TRUE;
+  DBUG_VOID_RETURN;
 }
 
 
@@ -527,7 +570,8 @@ void Protocol::init(THD *thd_arg)
 
 void Protocol::end_partial_result_set(THD *thd_arg)
 {
-  net_send_eof(thd_arg, thd_arg->server_status, 0 /* no warnings, we're inside SP */);
+  net_send_eof(thd_arg, thd_arg->server_status,
+               0 /* no warnings, we're inside SP */);
 }
 
 
@@ -573,7 +617,7 @@ bool Protocol::send_fields(List<Item> *list, uint flags)
   Protocol_text prot(thd);
   String *local_packet= prot.storage_packet();
   CHARSET_INFO *thd_charset= thd->variables.character_set_results;
-  DBUG_ENTER("send_fields");
+  DBUG_ENTER("Protocol::send_fields");
 
   if (flags & SEND_NUM_ROWS)
   {				// Packet with number of elements
@@ -588,6 +632,9 @@ bool Protocol::send_fields(List<Item> *list, uint flags)
   uint count= 0;
 #endif
 
+  /* We have to reallocate it here as a stored procedure may have reset it */
+  (void) local_packet->alloc(thd->variables.net_buffer_length);
+
   while ((item=it++))
   {
     char *pos;
@@ -827,10 +874,10 @@ bool Protocol::store_string_aux(const char *from, size_t length,
       fromcs != &my_charset_bin &&
       tocs != &my_charset_bin)
   {
-    uint dummy_errors;
-    return (convert->copy(from, length, fromcs, tocs, &dummy_errors) ||
-            net_store_data((uchar*) convert->ptr(), convert->length()));
+    /* Store with conversion */
+    return net_store_data((uchar*) from, length, fromcs, tocs);
   }
+  /* Store without conversion */
   return net_store_data((uchar*) from, length);
 }
 
@@ -856,8 +903,8 @@ bool Protocol_text::store(const char *from, size_t length,
 {
   CHARSET_INFO *tocs= this->thd->variables.character_set_results;
 #ifndef DBUG_OFF
-  DBUG_PRINT("info", ("Protocol_text::store field %u (%u): %s", field_pos,
-                      field_count, (length == 0? "" : from)));
+  DBUG_PRINT("info", ("Protocol_text::store field %u (%u): %.*s", field_pos,
+                      field_count, (int) length, (length == 0? "" : from)));
   DBUG_ASSERT(field_pos < field_count);
   DBUG_ASSERT(field_types == 0 ||
 	      field_types[field_pos] == MYSQL_TYPE_DECIMAL ||