From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 17 Mar 2009 11:58:07 +0000 (+0000)
Subject: Add Memory class
X-Git-Tag: io-1.1~1
X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=commitdiff_plain;h=7c6c7369eb6a2e63c466e3823ea729c72d5c55d3

Add Memory class
---

diff --git a/source/memory.cpp b/source/memory.cpp
new file mode 100644
index 0000000..c44554a
--- /dev/null
+++ b/source/memory.cpp
@@ -0,0 +1,134 @@
+/* $Id$
+
+This file is part of libmspio
+Copyright © 2009 Mikko Rasa, Mikkosoft Productions
+Distributed under the LGPL
+*/
+
+#include <algorithm>
+#include <cstring>
+#include "except.h"
+#include "memory.h"
+
+using namespace std;
+
+namespace Msp {
+namespace IO {
+
+Memory::Memory(char *d, unsigned s)
+{
+	init(d, d+s, M_RDWR);
+}
+
+Memory::Memory(char *b, char *e)
+{
+	init(b, e, M_RDWR);
+}
+
+Memory::Memory(const char *cd, unsigned s)
+{
+	char *d=const_cast<char *>(cd);
+	init(d, d+s, M_READ);
+}
+
+Memory::Memory(const char *b, const char *e)
+{
+	init(const_cast<char *>(b), const_cast<char *>(e), M_READ);
+}
+
+void Memory::init(char *b, char *e, Mode m)
+{
+	begin=b;
+	end=e;
+	pos=begin;
+	mode=m;
+}
+
+unsigned Memory::put(char c)
+{
+	check_mode(M_WRITE);
+	*pos++=c;
+	return 1;
+}
+
+bool Memory::getline(string &line)
+{
+	char *nl=find(pos, end, '\n');
+	line.assign(pos, nl);
+	bool result=(nl!=pos);
+	pos=nl;
+	return result;
+}
+
+int Memory::get()
+{
+	if(pos==end)
+	{
+		eof_flag=true;
+		return -1;
+	}
+
+	return static_cast<unsigned char>(*pos++);
+}
+
+unsigned Memory::seek(int off, SeekType type)
+{
+	char *new_pos;
+	if(type==S_BEG)
+		new_pos=begin+off;
+	else if(type==S_CUR)
+		new_pos=pos+off;
+	else if(type==S_END)
+		new_pos=end+off;
+	else
+		throw InvalidParameterValue("Invalid seek type");
+
+	if(new_pos<begin || new_pos>end)
+		throw InvalidParameterValue("Invalid seek offset");
+
+	pos=new_pos;
+	return pos-begin;
+}
+
+Handle Memory::get_event_handle()
+{
+	throw Exception("Memory doesn't support events");
+}
+
+unsigned Memory::do_write(const char *buf, unsigned size)
+{
+	check_mode(M_WRITE);
+
+	size=min<unsigned>(size, end-pos);
+	memcpy(pos, buf, size);
+	pos+=size;
+	return size;
+}
+
+unsigned Memory::do_read(char *buf, unsigned size)
+{
+	if(pos==end)
+	{
+		eof_flag=true;
+		return 0;
+	}
+
+	size=min<unsigned>(size, end-pos);
+	memcpy(buf, pos, size);
+	pos+=size;
+	return size;
+}
+
+void Memory::check_mode(Mode m) const
+{
+	if(m==M_WRITE)
+	{
+		if(!(mode&M_WRITE))
+			throw InvalidState("Memory is not writable");
+		if(pos==end)
+			throw InvalidState("Attempt to write past end of Memory");
+	}
+}
+
+} // namespace IO
+} // namespace Msp
diff --git a/source/memory.h b/source/memory.h
new file mode 100644
index 0000000..7ff5316
--- /dev/null
+++ b/source/memory.h
@@ -0,0 +1,48 @@
+/* $Id$
+
+This file is part of libmspio
+Copyright © 2009 Mikko Rasa, Mikkosoft Productions
+Distributed under the LGPL
+*/
+
+#ifndef MSP_IO_MEMORY_H_
+#define MSP_IO_MEMORY_H_
+
+#include "base.h"
+#include "seek.h"
+
+namespace Msp {
+namespace IO {
+
+class Memory: public Base
+{
+private:
+	char *begin;
+	char *end;
+	char *pos;
+
+public:
+	Memory(char *, unsigned);
+	Memory(char *, char *);
+	Memory(const char *, unsigned);
+	Memory(const char *, const char *);
+private:
+	void init(char *, char *, Mode);
+
+public:
+	virtual unsigned put(char);
+	virtual bool getline(std::string &);
+	virtual int get();
+	unsigned seek(int, SeekType);
+	unsigned tell() const { return pos-begin; }
+	virtual Handle get_event_handle();
+private:
+	virtual unsigned do_write(const char *, unsigned);
+	virtual unsigned do_read(char *, unsigned);
+	void check_mode(Mode) const;
+};
+
+} // namespace IO
+} // namespace Msp
+
+#endif