4. MSCGEN (message sequence charts generator)#

mscgetnはblockdiagとは独立なプログラムで、ネットワークプロトコルのようなメッセージシークエンスを表示する画像を生成します。 sphinxcontrib-mscgenとともにmscgenプログラムをインストールする必要があります。 mscgenはblockdiagとおなじくgraphvizの DOT formatの影響をうけた形式の指令を使います。

sphinxconrib-mscgen example.

msc {
hscale="0.5";
a,b,c;
a -> b [ label = " ab()" ];
b -> c [ label = "bc(TRUE)" ];
c => c [ label = "process()" ];
}

リスト 4.1 mscgenへの入力例#

.. msc::
   hscale="0.5";
   a,b,c;
   a -> b [ label = " ab()" ];
   b -> c [ label = "bc(TRUE)" ];
   c => c [ label = "process()" ];

Alice -\\ Bob : ab()
Bob -// Charie : bc(TRUE)
Charie --> Charie : process() — 図 4.1 PlantUML で書き換えて見ます。#

Quote from website:

Mscgen is a small program that parses Message Sequence Chart
descriptions and produces PNG, SVG, EPS or server side image maps
(ismaps) as the output. Message Sequence Charts (MSCs) are a way
of representing entities and interactions over some time period
and are often used in combination with SDL. MSCs are popular in
Telecoms to specify how protocols operate although MSCs need not
be complicated to create or use. Mscgen aims to provide a simple
text language that is clear to create, edit and understand, which
can also be transformed into common image formats for display or
printing.

4.1. MSC for some fictional process#

$msc{ hscale = "2"; a,b,c; a->b [ label = "ab()" ] ; b->c [ label = "bc(TRUE)"]; c=>c [ label = "process(1)" ]; c=>c [ label = "process(2)" ]; ...; c=>c [ label = "process(n)" ]; c=>c [ label = "process(END)" ]; a<<=c [ label = "callback()"]; --- [ label = "If more to run", ID="*" ]; a->a [ label = "next()"]; a->c [ label = "ac1()\nac2()"]; b<-c [ label = "cb(TRUE)"]; b->b [ label = "stalled(...)"]; a<-b [ label = "ab() = FALSE"]; }$

skinparam responseMessageBelowArrow true
a->b: ab()
b->c: bc(TRUE)
c -->c: process(1)
c -->c:process(2)
|||
c--> c: process(n)
c--> c: process(END)
a <<--c: callback()
== If more to run* ==
a<-a: next()
a->c: ac1() \nac2()
b<-c: cb(TRUE)
b->b: stalled(...)
a<-b: ab() = FALSE — 図 4.2 PlantUML version#

Example rendered MSC

# Fictional client-server protocol

msc {
arcgradient = 8;

a [label="Client"],b [label="Server"];

a=>b [label="data1"];
a-xb [label="data2"];
a=>b [label="data3"];
a<=b [label="ack1, nack2"];
a=>b [label="data2", arcskip="1"];
|||;
a<=b [label="ack3"];
|||;
}

MSCGEN (message sequence charts generator)

目次

4. MSCGEN (message sequence charts generator)#

4.1. MSC for some fictional process#