Mercurial > squish / file diff

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vio/vio.lua	Sun Jul 26 00:56:13 2009 +0100
@@ -0,0 +1,61 @@
+local vio = {};
+vio.__index = vio; 
+	
+function vio.open(string)
+	return setmetatable({ pos = 1, data = string }, vio);
+end
+
+function vio:read(format, ...)
+	if self.pos >= #self.data then return; end
+	if format == "*a" then
+		local oldpos = self.pos;
+		self.pos = #self.data;
+		return self.data:sub(oldpos, self.pos);
+	elseif format == "*l" then
+		local data;
+		data, self.pos = self.data:match("([^\r\n]*)\r?\n?()", self.pos)
+		return data;
+	elseif format == "*n" then
+		local data;
+		data, self.pos = self.data:match("(%d+)()", self.pos)
+		return tonumber(data);	
+	elseif type(format) == "number" then
+		local oldpos = self.pos;
+		self.pos = self.pos + format;
+		return self.data:sub(oldpos, self.pos-1);
+	end
+end
+
+function vio:seek(whence, offset)
+	if type(whence) == "number" then
+		whence, offset = "cur", whence;
+	end
+	offset = offset or 0;
+	
+	if whence == "cur" then
+		self.pos = self.pos + offset;
+	elseif whence == "set" then
+		self.pos = offset + 1;
+	elseif whence == "end" then
+		self.pos = #self.data - offset;
+	end
+	
+	return self.pos;
+end
+
+local function _readline(f) return f:read("*l"); end
+function vio:lines()
+	return _readline, self;
+end
+
+function vio:write(...)
+	for i=1,select('#', ...) do
+		local dat = tostring(select(i, ...));
+		self.data = self.data:sub(1, self.pos-1)..dat..self.data:sub(self.pos+#dat, -1);
+	end
+end
+
+function vio:close()
+	self.pos, self.data = nil, nil;
+end
+