* Buffer.new -> Buffer.of_size

* introduced Buffer.from_string

Author: mneumann

lib/buffer.rb

@@ -7,12 +7,19 @@ class Buffer
   class Error < RuntimeError; end
   class EOF < Error; end 
 
-  def initialize(size)
+  def self.from_string(str)
+    new(str)
+  end
+
+  def self.of_size(size)
     raise ArgumentError if size < 0
+    new('#' * size)
+  end 
 
-    @size = size
+  def initialize(content)
+    @size = content.size
+    @content = content
     @position = 0
-    @content = "#" * @size
   end
 
   def size
@@ -58,10 +65,11 @@ def copy_from_stream(stream, n)
       write(str)
       n -= str.size
     end
+    raise if n < 0 
   end
 
   def write_cstring(cstr)
-    raise ArgumentError, "Invalid Ruby/cstring" if cstr.include?("\000")
+    raise ArgumentError, "Invalid Ruby/cstring" if cstr.include?(0)
     write(cstr)
     write("\000")
   end

lib/postgres-pr/message.rb

@@ -34,7 +34,7 @@ def self.read(stream, startup=false)
     raise ParseError unless length >= 4
 
     # initialize buffer
-    buffer = Buffer.new(startup ? length : 1+length)
+    buffer = Buffer.of_size(startup ? length : 1+length)
     buffer.write_byte(type) unless startup
     buffer.write_int32_network(length)
     buffer.copy_from_stream(stream, length-4)
@@ -53,7 +53,7 @@ def self.dump(*args)
   end
 
   def dump(body_size=0)
-    buffer = Buffer.new(5 +  body_size)
+    buffer = Buffer.of_size(5 +  body_size)
     buffer.write_byte(self.message_type)
     buffer.write_int32_network(4 + body_size)
     yield buffer if block_given?
@@ -462,7 +462,7 @@ class StartupMessage < Message
   def dump
     sz = @params.inject(4 + 4) {|sum, kv| sum + kv[0].size + 1 + kv[1].size + 1} + 1
 
-    buffer = Buffer.new(sz)
+    buffer = Buffer.of_size(sz)
     buffer.write_int32_network(sz)
     buffer.write_int32_network(@proto_version)
     @params.each_pair {|key, value| 
@@ -498,7 +498,7 @@ class SSLRequest < Message
 
   def dump
     sz = 4 + 4
-    buffer = Buffer.new(sz)
+    buffer = Buffer.of_size(sz)
     buffer.write_int32_network(sz)
     buffer.write_int32_network(@ssl_request_code)
     raise DumpError unless buffer.at_end?