Merged 5.1 with maria 5.1

3 files changed, 103 insertions, 44 deletions

diff --git a/libmysql/dll.c b/libmysql/dll.c
index 7aa3b5bf96f..8fcf41c792c 100644
--- a/libmysql/dll.c
+++ b/libmysql/dll.c
@@ -89,9 +89,20 @@ BOOL APIENTRY LibMain(HANDLE hInst,DWORD ul_reason_being_called,
   UNREFERENCED_PARAMETER(lpReserved);
 } /* LibMain */
 
+
+static BOOL do_libmain;
 int __stdcall DllMain(HANDLE hInst,DWORD ul_reason_being_called,LPVOID lpReserved)
 {
-  return LibMain(hInst,ul_reason_being_called,lpReserved);
+  /*
+    Unless environment variable LIBMYSQL_DLLINIT is set, do nothing.
+    The environment variable is checked once, during the first call to DllMain()
+    (in DLL_PROCESS_ATTACH hook).
+  */
+  if (ul_reason_being_called == DLL_PROCESS_ATTACH)
+    do_libmain = (getenv("LIBMYSQL_DLLINIT") != NULL);
+  if (do_libmain)
+    return LibMain(hInst,ul_reason_being_called,lpReserved);
+  return TRUE;
 }
 
 #elif defined(WINDOWS)
diff --git a/libmysql/errmsg.c b/libmysql/errmsg.c
index e7f495d1f43..95ee6862aa8 100644
--- a/libmysql/errmsg.c
+++ b/libmysql/errmsg.c
@@ -84,6 +84,7 @@ const char *client_errors[]=
   "This feature is not implemented yet",
   "Lost connection to MySQL server at '%s', system error: %d",
   "Statement closed indirectly because of a preceeding %s() call",
+  "The number of columns in the result set differs from the number of bound buffers. You must reset the statement, rebind the result set columns, and execute the statement again",
   ""
 };
 
@@ -149,6 +150,7 @@ const char *client_errors[]=
   "This feature is not implemented yet",
   "Lost connection to MySQL server at '%s', system error: %d",
   "Statement closed indirectly because of a preceeding %s() call",
+  "The number of columns in the result set differs from the number of bound buffers. You must reset the statement, rebind the result set columns, and execute the statement again",
   ""
 };
 
@@ -212,6 +214,7 @@ const char *client_errors[]=
   "This feature is not implemented yet",
   "Lost connection to MySQL server at '%s', system error: %d",
   "Statement closed indirectly because of a preceeding %s() call",
+  "The number of columns in the result set differs from the number of bound buffers. You must reset the statement, rebind the result set columns, and execute the statement again",
   ""
 };
 #endif
diff --git a/libmysql/libmysql.c b/libmysql/libmysql.c
index 98eb7156de0..c7d5997094a 100644
--- a/libmysql/libmysql.c
+++ b/libmysql/libmysql.c
@@ -1706,6 +1706,7 @@ static my_bool setup_one_fetch_function(MYSQL_BIND *, MYSQL_FIELD *field);
 #define RESET_SERVER_SIDE 1
 #define RESET_LONG_DATA 2
 #define RESET_STORE_RESULT 4
+#define RESET_CLEAR_ERROR 8
 
 static my_bool reset_stmt_handle(MYSQL_STMT *stmt, uint flags);
 
@@ -2090,7 +2091,7 @@ mysql_stmt_prepare(MYSQL_STMT *stmt, const char *query, ulong length)
   To be removed when all commands will fully support prepared mode.
 */
 
-static unsigned int alloc_stmt_fields(MYSQL_STMT *stmt)
+static void alloc_stmt_fields(MYSQL_STMT *stmt)
 {
   MYSQL_FIELD *fields, *field, *end;
   MEM_ROOT *alloc= &stmt->mem_root;
@@ -2108,7 +2109,10 @@ static unsigned int alloc_stmt_fields(MYSQL_STMT *stmt)
       !(stmt->bind= (MYSQL_BIND *) alloc_root(alloc,
 					      sizeof(MYSQL_BIND) *
 					      stmt->field_count)))
-    return 0;
+  {
+    set_stmt_error(stmt, CR_OUT_OF_MEMORY, unknown_sqlstate, NULL);
+    return;
+  }
 
   for (fields= mysql->fields, end= fields+stmt->field_count,
 	 field= stmt->fields;
@@ -2127,13 +2131,15 @@ static unsigned int alloc_stmt_fields(MYSQL_STMT *stmt)
     field->def      = fields->def ? strdup_root(alloc,fields->def): 0;
     field->max_length= 0;
   }
-  return stmt->field_count;
 }
 
 
-/*
+/**
   Update result set columns metadata if it was sent again in
   reply to COM_STMT_EXECUTE.
+
+  @note If the new field count is different from the original one,
+        an error is set and no update is performed.
 */
 
 static void update_stmt_fields(MYSQL_STMT *stmt)
@@ -2143,7 +2149,22 @@ static void update_stmt_fields(MYSQL_STMT *stmt)
   MYSQL_FIELD *stmt_field= stmt->fields;
   MYSQL_BIND *my_bind= stmt->bind_result_done ? stmt->bind : 0;
 
-  DBUG_ASSERT(stmt->field_count == stmt->mysql->field_count);
+  if (stmt->field_count != stmt->mysql->field_count)
+  {
+    /*
+      The tables used in the statement were altered,
+      and the query now returns a different number of columns.
+      There is no way to continue without reallocating the bind
+      array:
+      - if the number of columns increased, mysql_stmt_fetch()
+      will write beyond allocated memory
+      - if the number of columns decreased, some user-bound
+      buffers will be left unassigned without user knowing
+      that.
+    */
+    set_stmt_error(stmt, CR_NEW_STMT_METADATA, unknown_sqlstate, NULL);
+    return;
+  }
 
   for (; field < field_end; ++field, ++stmt_field)
   {
@@ -2792,6 +2813,50 @@ my_bool STDCALL mysql_stmt_attr_get(MYSQL_STMT *stmt,
 }
 
 
+/**
+  Update statement result set metadata from with the new field
+  information sent during statement execute.
+
+  @pre mysql->field_count is not zero
+
+  @retval TRUE   if error: out of memory or the new
+                 result set has a different number of columns
+  @retval FALSE  success
+*/
+
+static void reinit_result_set_metadata(MYSQL_STMT *stmt)
+{
+  /* Server has sent result set metadata */
+  if (stmt->field_count == 0)
+  {
+    /*
+      This is 'SHOW'/'EXPLAIN'-like query. Current implementation of
+      prepared statements can't send result set metadata for these queries
+      on prepare stage. Read it now.
+    */
+    alloc_stmt_fields(stmt);
+  }
+  else
+  {
+    /*
+      Update result set metadata if it for some reason changed between
+      prepare and execute, i.e.:
+      - in case of 'SELECT ?' we don't know column type unless data was
+      supplied to mysql_stmt_execute, so updated column type is sent
+      now.
+      - if data dictionary changed between prepare and execute, for
+      example a table used in the query was altered.
+      Note, that now (4.1.3) we always send metadata in reply to
+      COM_STMT_EXECUTE (even if it is not necessary), so either this or
+      previous branch always works.
+      TODO: send metadata only when it's really necessary and add a warning
+      'Metadata changed' when it's sent twice.
+      */
+    update_stmt_fields(stmt);
+  }
+}
+
+
 /*
   Send placeholders data to server (if there are placeholders)
   and execute prepared statement.
@@ -2847,7 +2912,7 @@ int STDCALL mysql_stmt_execute(MYSQL_STMT *stmt)
     DBUG_RETURN(1);
   }
 
-  if (reset_stmt_handle(stmt, RESET_STORE_RESULT))
+  if (reset_stmt_handle(stmt, RESET_STORE_RESULT | RESET_CLEAR_ERROR))
     DBUG_RETURN(1);
   /*
     No need to check for stmt->state: if the statement wasn't
@@ -2855,40 +2920,10 @@ int STDCALL mysql_stmt_execute(MYSQL_STMT *stmt)
   */
   if (mysql->methods->stmt_execute(stmt))
     DBUG_RETURN(1);
-  if (mysql->field_count)
-  {
-    /* Server has sent result set metadata */
-    if (stmt->field_count == 0)
-    {
-      /*
-        This is 'SHOW'/'EXPLAIN'-like query. Current implementation of
-        prepared statements can't send result set metadata for these queries
-        on prepare stage. Read it now.
-      */
-      alloc_stmt_fields(stmt);
-    }
-    else
-    {
-      /*
-        Update result set metadata if it for some reason changed between
-        prepare and execute, i.e.:
-        - in case of 'SELECT ?' we don't know column type unless data was
-          supplied to mysql_stmt_execute, so updated column type is sent
-          now.
-        - if data dictionary changed between prepare and execute, for
-          example a table used in the query was altered.
-        Note, that now (4.1.3) we always send metadata in reply to
-        COM_STMT_EXECUTE (even if it is not necessary), so either this or
-        previous branch always works.
-        TODO: send metadata only when it's really necessary and add a warning
-        'Metadata changed' when it's sent twice.
-      */
-      update_stmt_fields(stmt);
-    }
-  }
   stmt->state= MYSQL_STMT_EXECUTE_DONE;
-  if (stmt->field_count)
+  if (mysql->field_count)
   {
+    reinit_result_set_metadata(stmt);
     if (stmt->server_status & SERVER_STATUS_CURSOR_EXISTS)
     {
       mysql->status= MYSQL_STATUS_READY;
@@ -2903,7 +2938,7 @@ int STDCALL mysql_stmt_execute(MYSQL_STMT *stmt)
         network or b) is more efficient if all (few) result set rows are
         precached on client and server's resources are freed.
       */
-      DBUG_RETURN(mysql_stmt_store_result(stmt));
+      mysql_stmt_store_result(stmt);
     }
     else
     {
@@ -2912,7 +2947,7 @@ int STDCALL mysql_stmt_execute(MYSQL_STMT *stmt)
       stmt->read_row_func= stmt_read_row_unbuffered;
     }
   }
-  DBUG_RETURN(0);
+  DBUG_RETURN(test(stmt->last_errno));
 }
 
 
@@ -4765,6 +4800,12 @@ int STDCALL mysql_stmt_store_result(MYSQL_STMT *stmt)
     DBUG_RETURN(1);
   }
 
+  if (stmt->last_errno)
+  {
+    /* An attempt to use an invalid statement handle. */
+    DBUG_RETURN(1);
+  }
+
   if (mysql->status == MYSQL_STATUS_READY &&
       stmt->server_status & SERVER_STATUS_CURSOR_EXISTS)
   {
@@ -4972,9 +5013,10 @@ static my_bool reset_stmt_handle(MYSQL_STMT *stmt, uint flags)
           stmt->state= MYSQL_STMT_INIT_DONE;
           return 1;
         }
-        stmt_clear_error(stmt);
       }
     }
+    if (flags & RESET_CLEAR_ERROR)
+      stmt_clear_error(stmt);
     stmt->state= MYSQL_STMT_PREPARE_DONE;
   }
   return 0;
@@ -4985,7 +5027,8 @@ my_bool STDCALL mysql_stmt_free_result(MYSQL_STMT *stmt)
   DBUG_ENTER("mysql_stmt_free_result");
 
   /* Free the client side and close the server side cursor if there is one */
-  DBUG_RETURN(reset_stmt_handle(stmt, RESET_LONG_DATA | RESET_STORE_RESULT));
+  DBUG_RETURN(reset_stmt_handle(stmt, RESET_LONG_DATA | RESET_STORE_RESULT |
+                                RESET_CLEAR_ERROR));
 }
 
 /********************************************************************
@@ -5066,7 +5109,9 @@ my_bool STDCALL mysql_stmt_reset(MYSQL_STMT *stmt)
     DBUG_RETURN(1);
   }
   /* Reset the client and server sides of the prepared statement */
-  DBUG_RETURN(reset_stmt_handle(stmt, RESET_SERVER_SIDE | RESET_LONG_DATA));
+  DBUG_RETURN(reset_stmt_handle(stmt,
+                                RESET_SERVER_SIDE | RESET_LONG_DATA |
+                                RESET_CLEAR_ERROR));
 }
 
 /*