Added regular expression and memory buffer files.

git-svn-id: http://svn.zoneminder.com/svn/zm/trunk@944 e3e1d417-86f3-4887-817a-d78f3d33393f

src/zm_buffer.cpp

@@ -0,0 +1,65 @@
+/*
+ * ZoneMinder flexible memory class implementation, $Date$, $Revision$
+ * Copyright (C) 2003  Philip Coombes
+ * 
+ * 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 the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+*/ 
+
+#include <string.h>
+
+#include "zm.h"
+#include "zm_buffer.h"
+
+unsigned int Buffer::Assign( const unsigned char *p_storage, unsigned int p_size )
+{
+	delete[] storage;
+	size = allocation = p_size;
+	head = storage = new unsigned char[size];
+	memcpy( storage, p_storage, size );
+	tail = head + size;
+	return( size );
+}
+
+unsigned int Buffer::Expand( unsigned int count )
+{
+	int spare = allocation - size;
+	int head_space = head - storage;
+	int tail_space = spare - head_space;
+	int width = tail - head;
+	if ( spare > count )
+	{
+		if ( tail_space < count )
+		{
+			memmove( storage, head, size );
+			head = storage;
+			tail = head + width;
+		}
+	}
+	else
+	{
+		allocation += count;
+		unsigned char *new_storage = new unsigned char[allocation];
+		if ( storage )
+		{
+			memcpy( new_storage, storage, size );
+			delete[] storage;
+		}
+		storage = new_storage;
+		head = storage;
+		tail = head + width;
+	}
+	size += count;
+	return( size );
+}