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/*++
/* NAME
/* master 3h
/* SUMMARY
/* Postfix master - data structures and prototypes
/* SYNOPSIS
/* #include "master.h"
/* DESCRIPTION
/* .nf
/*
* Server processes that provide the same service share a common "listen"
* socket to accept connection requests, and share a common pipe to the
* master process to send status reports. Server processes die voluntarily
* when idle for a configurable amount of time, or after servicing a
* configurable number of requests; the master process spawns new processes
* on demand up to a configurable concurrency limit and/or periodically.
*/
typedef struct MASTER_SERV {
int flags; /* status, features, etc. */
char *name; /* service endpoint name */
int type; /* UNIX-domain, INET, etc. */
int wakeup_time; /* wakeup interval */
int *listen_fd; /* incoming requests */
int listen_fd_count; /* nr of descriptors */
union {
struct INET_ADDR_LIST *inet;
} addr_list;
int max_proc; /* upper bound on # processes */
char *path; /* command pathname */
struct ARGV *args; /* argument vector */
int avail_proc; /* idle processes */
int total_proc; /* number of processes */
int throttle_delay; /* failure recovery parameter */
int status_fd[2]; /* child status reports */
struct BINHASH *children; /* linkage */
struct MASTER_SERV *next; /* linkage */
} MASTER_SERV;
/*
* Per-service flag bits. We assume trouble when a child process terminates
* before completing its first request: either the program is defective,
* some configuration is wrong, or the system is out of resources.
*/
#define MASTER_FLAG_THROTTLE (1<<0) /* we're having trouble */
#define MASTER_FLAG_MARK (1<<1) /* garbage collection support */
#define MASTER_THROTTLED(f) ((f)->flags & MASTER_FLAG_THROTTLE)
#define MASTER_LIMIT_OK(limit, count) ((limit) == 0 || ((count) < (limit)))
/*
* Service types.
*/
#define MASTER_SERV_TYPE_UNIX 1 /* AF_UNIX domain socket */
#define MASTER_SERV_TYPE_INET 2 /* AF_INET domain socket */
#define MASTER_SERV_TYPE_FIFO 3 /* fifo (named pipe) */
/*
* Default process management policy values. This is only the bare minimum.
* Most policy management is delegated to child processes. The process
* manager runs at high privilege level and has to be kept simple.
*/
#define MASTER_DEF_MIN_IDLE 1 /* preferred # of idle processes */
/*
* Structure of child process.
*/
typedef int MASTER_PID; /* pid is key into binhash table */
typedef struct MASTER_PROC {
MASTER_PID pid; /* child process id */
int avail; /* availability */
MASTER_SERV *serv; /* parent linkage */
int use_count; /* number of service requests */
} MASTER_PROC;
/*
* Other manifest constants.
*/
#define MASTER_BUF_LEN 2048 /* logical config line length */
/*
* master_ent.c
*/
extern void fset_master_ent(char *);
extern void set_master_ent(void);
extern void end_master_ent(void);
extern void print_master_ent(MASTER_SERV *);
extern MASTER_SERV *get_master_ent(void);
extern void free_master_ent(MASTER_SERV *);
/*
* master_conf.c
*/
extern void master_config(void);
extern void master_refresh(void);
/*
* master_vars.c
*/
extern char *var_program_dir;
extern int var_proc_limit;
extern int var_use_limit;
extern int var_idle_limit;
extern void master_vars_init(void);
/*
* master_tab.c
*/
extern MASTER_SERV *master_head;
extern void master_start_service(MASTER_SERV *);
extern void master_stop_service(MASTER_SERV *);
extern void master_restart_service(MASTER_SERV *);
/*
* master_events.c
*/
extern int master_gotsighup;
extern int master_gotsigchld;
extern void master_sigsetup(void);
/*
* master_status.c
*/
extern void master_status_init(MASTER_SERV *);
extern void master_status_cleanup(MASTER_SERV *);
/*
* master_wakeup.c
*/
extern void master_wakeup_init(MASTER_SERV *);
extern void master_wakeup_cleanup(MASTER_SERV *);
/*
* master_listen.c
*/
extern void master_listen_init(MASTER_SERV *);
extern void master_listen_cleanup(MASTER_SERV *);
/*
* master_avail.c
*/
extern void master_avail_listen(MASTER_SERV *);
extern void master_avail_cleanup(MASTER_SERV *);
extern void master_avail_more(MASTER_SERV *, MASTER_PROC *);
extern void master_avail_less(MASTER_SERV *, MASTER_PROC *);
/*
* master_spawn.c
*/
extern struct BINHASH *master_child_table;
extern void master_spawn(MASTER_SERV *);
extern void master_reap_child(void);
extern void master_delete_children(MASTER_SERV *);
/* DIAGNOSTICS
/* BUGS
/* SEE ALSO
/* 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
/*--*/
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