1 /* $NetBSD: master.h,v 1.3 2025/02/25 19:15:46 christos Exp $ */ 2 3 /*++ 4 /* NAME 5 /* master 3h 6 /* SUMMARY 7 /* Postfix master - data structures and prototypes 8 /* SYNOPSIS 9 /* #include "master.h" 10 /* DESCRIPTION 11 /* .nf 12 13 /* 14 * Server processes that provide the same service share a common "listen" 15 * socket to accept connection requests, and share a common pipe to the 16 * master process to send status reports. Server processes die voluntarily 17 * when idle for a configurable amount of time, or after servicing a 18 * configurable number of requests; the master process spawns new processes 19 * on demand up to a configurable concurrency limit and/or periodically. 20 * 21 * The canonical service name is what we use internally, so that we correctly 22 * handle a request to "reload" after someone changes "smtp" into "25". 23 * 24 * We use the external service name from master.cf when reporting problems, so 25 * that the user can figure out what we are talking about. Of course we also 26 * include the canonical service name so that the UNIX-domain smtp service 27 * can be distinguished from the Internet smtp service. 28 */ 29 typedef struct MASTER_SERV { 30 int flags; /* status, features, etc. */ 31 char *ext_name; /* service endpoint name (master.cf) */ 32 char *name; /* service endpoint name (canonical) */ 33 int type; /* UNIX-domain, INET, etc. */ 34 time_t busy_warn_time; /* limit "all servers busy" warning */ 35 int wakeup_time; /* wakeup interval */ 36 int *listen_fd; /* incoming requests */ 37 int listen_fd_count; /* nr of descriptors */ 38 union { 39 struct { 40 char *port; /* inet listen port */ 41 struct INET_ADDR_LIST *addr;/* inet listen address */ 42 } inet_ep; 43 #define MASTER_INET_ADDRLIST(s) ((s)->endpoint.inet_ep.addr) 44 #define MASTER_INET_PORT(s) ((s)->endpoint.inet_ep.port) 45 } endpoint; 46 int max_proc; /* upper bound on # processes */ 47 char *path; /* command pathname */ 48 struct ARGV *args; /* argument vector */ 49 char *stress_param_val; /* stress value: "yes" or empty */ 50 time_t stress_expire_time; /* stress pulse stretcher */ 51 int avail_proc; /* idle processes */ 52 int total_proc; /* number of processes */ 53 int throttle_delay; /* failure recovery parameter */ 54 int status_fd[2]; /* child status reports */ 55 struct BINHASH *children; /* linkage */ 56 struct MASTER_SERV *next; /* linkage */ 57 } MASTER_SERV; 58 59 /* 60 * Per-service flag bits. We assume trouble when a child process terminates 61 * before completing its first request: either the program is defective, 62 * some configuration is wrong, or the system is out of resources. 63 */ 64 #define MASTER_FLAG_THROTTLE (1<<0) /* we're having trouble */ 65 #define MASTER_FLAG_MARK (1<<1) /* garbage collection support */ 66 #define MASTER_FLAG_CONDWAKE (1<<2) /* wake up if actually used */ 67 #define MASTER_FLAG_INETHOST (1<<3) /* endpoint name specifies host */ 68 #define MASTER_FLAG_LOCAL_ONLY (1<<4) /* no remote clients */ 69 #define MASTER_FLAG_LISTEN (1<<5) /* monitor this port */ 70 71 #define MASTER_THROTTLED(f) ((f)->flags & MASTER_FLAG_THROTTLE) 72 #define MASTER_MARKED_FOR_DELETION(f) ((f)->flags & MASTER_FLAG_MARK) 73 #define MASTER_LISTENING(f) ((f)->flags & MASTER_FLAG_LISTEN) 74 75 #define MASTER_LIMIT_OK(limit, count) ((limit) == 0 || ((count) < (limit))) 76 77 /* 78 * Service types, stream sockets unless indicated otherwise. 79 */ 80 #define MASTER_SERV_TYPE_UNIX 1 /* AF_UNIX domain socket */ 81 #define MASTER_SERV_TYPE_INET 2 /* AF_INET domain socket */ 82 #define MASTER_SERV_TYPE_FIFO 3 /* fifo (named pipe) */ 83 #define MASTER_SERV_TYPE_PASS 4 /* AF_UNIX domain socket */ 84 #define MASTER_SERV_TYPE_UXDG 5 /* AF_UNIX domain datagram socket */ 85 86 /* 87 * Default process management policy values. This is only the bare minimum. 88 * Most policy management is delegated to child processes. The process 89 * manager runs at high privilege level and has to be kept simple. 90 */ 91 #define MASTER_DEF_MIN_IDLE 1 /* preferred # of idle processes */ 92 93 /* 94 * Structure of child process. 95 */ 96 typedef int MASTER_PID; /* pid is key into binhash table */ 97 98 typedef struct MASTER_PROC { 99 MASTER_PID pid; /* child process id */ 100 unsigned gen; /* child generation number */ 101 int avail; /* availability */ 102 MASTER_SERV *serv; /* parent linkage */ 103 int use_count; /* number of service requests */ 104 } MASTER_PROC; 105 106 /* 107 * Other manifest constants. 108 */ 109 #define MASTER_BUF_LEN 2048 /* logical config line length */ 110 111 /* 112 * master.c 113 */ 114 extern int master_detach; 115 extern int init_mode; 116 117 /* 118 * master_ent.c 119 */ 120 extern void fset_master_ent(char *); 121 extern void set_master_ent(void); 122 extern void end_master_ent(void); 123 extern void print_master_ent(MASTER_SERV *); 124 extern MASTER_SERV *get_master_ent(void); 125 extern void free_master_ent(MASTER_SERV *); 126 127 /* 128 * master_conf.c 129 */ 130 extern void master_config(void); 131 extern void master_refresh(void); 132 133 /* 134 * master_vars.c 135 */ 136 extern void master_vars_init(void); 137 138 /* 139 * master_service.c 140 */ 141 extern MASTER_SERV *master_head; 142 extern void master_start_service(MASTER_SERV *); 143 extern void master_stop_service(MASTER_SERV *); 144 extern void master_restart_service(MASTER_SERV *, int); 145 146 #define DO_CONF_RELOAD 1 /* config files were reloaded */ 147 #define NO_CONF_RELOAD 0 /* no config file was reloaded */ 148 149 /* 150 * master_events.c 151 */ 152 extern int master_gotsighup; 153 extern int master_gotsigchld; 154 extern void master_sigsetup(void); 155 156 /* 157 * master_status.c 158 */ 159 extern void master_status_init(MASTER_SERV *); 160 extern void master_status_cleanup(MASTER_SERV *); 161 162 /* 163 * master_wakeup.c 164 */ 165 extern void master_wakeup_init(MASTER_SERV *); 166 extern void master_wakeup_cleanup(MASTER_SERV *); 167 168 169 /* 170 * master_listen.c 171 */ 172 extern void master_listen_init(MASTER_SERV *); 173 extern void master_listen_cleanup(MASTER_SERV *); 174 175 /* 176 * master_avail.c 177 */ 178 extern void master_avail_listen(MASTER_SERV *); 179 extern void master_avail_cleanup(MASTER_SERV *); 180 extern void master_avail_more(MASTER_SERV *, MASTER_PROC *); 181 extern void master_avail_less(MASTER_SERV *, MASTER_PROC *); 182 183 /* 184 * master_spawn.c 185 */ 186 extern struct BINHASH *master_child_table; 187 extern void master_spawn(MASTER_SERV *); 188 extern void master_reap_child(void); 189 extern void master_delete_children(MASTER_SERV *); 190 191 /* 192 * master_flow.c 193 */ 194 extern void master_flow_init(void); 195 extern int master_flow_pipe[2]; 196 197 /* 198 * master_watch.c 199 * 200 * Support to warn about main.cf parameters that can only be initialized but 201 * not updated, and to initialize or update data structures that derive 202 * values from main.cf parameters. 203 */ 204 typedef struct { 205 const char *name; /* parameter name */ 206 char **value; /* current main.cf value */ 207 char **backup; /* actual value that is being used */ 208 int flags; /* see below */ 209 void (*notify) (void); /* init or update data structure */ 210 } MASTER_STR_WATCH; 211 212 typedef struct { 213 const char *name; /* parameter name */ 214 int *value; /* current main.cf value */ 215 int backup; /* actual value that is being used */ 216 int flags; /* see below */ 217 void (*notify) (void); /* init or update data structure */ 218 } MASTER_INT_WATCH; 219 220 #define MASTER_WATCH_FLAG_UPDATABLE (1<<0) /* support update after init */ 221 #define MASTER_WATCH_FLAG_ISSET (1<<1) /* backup is initialized */ 222 223 extern void master_str_watch(const MASTER_STR_WATCH *); 224 extern void master_int_watch(MASTER_INT_WATCH *); 225 226 /* 227 * master_monitor.c 228 */ 229 extern int master_monitor(int); 230 231 /* DIAGNOSTICS 232 /* BUGS 233 /* SEE ALSO 234 /* LICENSE 235 /* .ad 236 /* .fi 237 /* The Secure Mailer license must be distributed with this software. 238 /* AUTHOR(S) 239 /* Wietse Venema 240 /* IBM T.J. Watson Research 241 /* P.O. Box 704 242 /* Yorktown Heights, NY 10598, USA 243 /* 244 /* Wietse Venema 245 /* Google, Inc. 246 /* 111 8th Avenue 247 /* New York, NY 10011, USA 248 /*--*/ 249