Initial commit: svc supervisor, design docs, session transcript

Existing work moved from /storage/vms/9front/svc, previously unversioned.
Object files and linked binaries excluded via .gitignore.

1 files changed, 85 insertions, 0 deletions

diff --git a/svc/src/dat.h b/svc/src/dat.h
new file mode 100644
index 0000000..f2cdec2
--- /dev/null
+++ b/svc/src/dat.h
@@ -0,0 +1,85 @@
+/*
+ * Shared between the supervisor (init.c) and the control
+ * filesystem (fs.c).
+ */
+
+enum
+{
+	/* states */
+	Sstopped,
+	Swaiting,	/* wants to run; a needs= is not up yet */
+	Sstarting,	/* started; not yet ready */
+	Srunning,
+	Sfailed,
+	Sdone,		/* ready=exit service that finished cleanly */
+
+	/* kinds, from ready= */
+	Kexec,		/* up as soon as started; watch the process */
+	Ksrv,		/* up when /srv/x appears; watch that file */
+	Kdial,		/* up when a dial succeeds; watch the process */
+	Kexit,		/* oneshot; done when it exits cleanly */
+
+	Maxargs		= 64,
+	Maxneeds	= 32,
+	Maxrestarts	= 5,		/* within Restartwindow seconds */
+	Restartwindow	= 60,
+	Restartwait	= 1,		/* seconds between restarts */
+	Readywait	= 30,		/* seconds to become ready */
+	Stopwait	= 5,		/* seconds before killing */
+	Tickms		= 250,		/* poll interval */
+};
+
+typedef struct Svc Svc;
+struct Svc
+{
+	char	*name;
+	char	*exec;
+	char	*argv[Maxargs];
+	int	argc;
+	char	*env[Maxargs];
+	int	envc;
+	char	*restart;
+	int	enable;
+
+	int	kind;
+	char	*readyarg;
+	char	*needs[Maxneeds];
+	int	nneeds;
+
+	int	wanted;			/* should it be running? */
+	int	stopping;		/* we asked it to go; not a crash */
+	int	pid;
+	int	state;
+	long	tstart;
+	long	tstop;			/* when we asked it to stop */
+	long	tretry;			/* earliest time to start again */
+	int	restarts;
+	long	rtimes[Maxrestarts];
+	int	rnext;
+	char	*exits;
+
+	int	mark;			/* cycle detection */
+	Svc	*next;
+};
+
+extern Svc	*svcs;
+extern char	*statename[];
+extern char	*svcdir;
+extern char	*logdir;
+extern int	verbose;
+extern QLock	statelock;	/* covers svcs and the command queue */
+
+/* init.c */
+Svc*	findname(char*);
+void	startsvc(Svc*);
+void	stopsvc(Svc*);
+char*	statusline(Svc*);	/* malloc'd ndb line, with newline */
+char*	allstatus(void);	/* malloc'd, every service */
+
+/* command queue: the filesystem asks, the supervisor acts */
+char*	queuecmd(char *verb, char *name);	/* nil ok, else error */
+void	draincmds(void);
+int	cmdspending(void);
+
+/* fs.c */
+void	startfs(char *srvname, char *mtpt);