diff options
Diffstat (limited to 'src/master/master_proto.h')
| -rw-r--r-- | src/master/master_proto.h | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/src/master/master_proto.h b/src/master/master_proto.h new file mode 100644 index 0000000..6084514 --- /dev/null +++ b/src/master/master_proto.h @@ -0,0 +1,75 @@ +/*++ +/* NAME +/* master_proto 3h +/* SUMMARY +/* master process protocol +/* SYNOPSIS +/* #include <master_proto.h> +/* DESCRIPTION +/* .nf + + /* + * Transport names. The master passes the transport name on the command + * line, and thus the name is part of the master to child protocol. + */ +#define MASTER_XPORT_NAME_UNIX "unix" /* local IPC */ +#define MASTER_XPORT_NAME_FIFO "fifo" /* local IPC */ +#define MASTER_XPORT_NAME_INET "inet" /* non-local IPC */ +#define MASTER_XPORT_NAME_PASS "pass" /* local IPC */ +#define MASTER_XPORT_NAME_UXDG "unix-dgram" /* local IPC */ + + /* + * Format of a status message sent by a child process to the process + * manager. Since this is between processes on the same machine we need not + * worry about byte order and word length. + */ +typedef struct MASTER_STATUS { + int pid; /* process ID */ + unsigned gen; /* child generation number */ + int avail; /* availability */ +} MASTER_STATUS; + +#define MASTER_GEN_NAME "GENERATION" /* passed via environment */ + +#define MASTER_STAT_TAKEN 0 /* this one is occupied */ +#define MASTER_STAT_AVAIL 1 /* this process is idle */ + +extern int master_notify(int, unsigned, int); /* encapsulate status msg */ + + /* + * File descriptors inherited from the master process. The flow control pipe + * is read by receive processes and is written to by send processes. If + * receive processes get too far ahead they will pause for a brief moment. + */ +#define MASTER_FLOW_READ 3 +#define MASTER_FLOW_WRITE 4 + + /* + * File descriptors inherited from the master process. All processes that + * provide a given service share the same status file descriptor, and listen + * on the same service socket(s). The kernel decides what process gets the + * next connection. Usually the number of listening processes is small, so + * one connection will not cause a "thundering herd" effect. When no process + * listens on a given socket, the master process will. MASTER_LISTEN_FD is + * actually the lowest-numbered descriptor of a sequence of descriptors to + * listen on. + */ +#define MASTER_STATUS_FD 5 /* shared channel to parent */ +#define MASTER_LISTEN_FD 6 /* accept connections here */ + +/* LICENSE +/* .ad +/* .fi +/* The Secure Mailer license must be distributed with this software. +/* AUTHOR(S) +/* Wietse Venema +/* IBM T.J. Watson Research +/* P.O. Box 704 +/* Yorktown Heights, NY 10598, USA +/* +/* Wietse Venema +/* Google, Inc. +/* 111 8th Avenue +/* New York, NY 10011, USA +/*--*/ + |