master-service.h   [plain text]

#ifndef MASTER_SERVICE_H
#define MASTER_SERVICE_H

#include "network.h"

enum master_service_flags {
	/* stdin/stdout already contains a client which we want to serve */
	MASTER_SERVICE_FLAG_STD_CLIENT		= 0x01,
	/* this process is currently running standalone without a master */
	MASTER_SERVICE_FLAG_STANDALONE		= 0x02,
	/* Log to configured log file instead of stderr. By default when
	   _FLAG_STANDALONE is set, logging is done to stderr. */
	MASTER_SERVICE_FLAG_DONT_LOG_TO_STDERR	= 0x04,
	/* Service is going to do multiple configuration lookups,
	   keep the connection to config service open. */
	MASTER_SERVICE_FLAG_KEEP_CONFIG_OPEN	= 0x08,
	/* Don't read settings, but use whatever is in environment */
	MASTER_SERVICE_FLAG_NO_CONFIG_SETTINGS	= 0x10,
	/* Use MASTER_LOGIN_NOTIFY_FD to track login overflow state */
	MASTER_SERVICE_FLAG_TRACK_LOGIN_STATE	= 0x40,
	/* If master sends SIGINT, don't die even if we don't have clients */
	MASTER_SERVICE_FLAG_NO_IDLE_DIE		= 0x80,
	/* Show number of connections in process title
	   (only if verbose_proctitle setting is enabled) */
	MASTER_SERVICE_FLAG_UPDATE_PROCTITLE	= 0x100
};

struct master_service_connection {
	int fd;
	int listen_fd;

	struct ip_addr remote_ip;
	unsigned int remote_port;

	unsigned int fifo:1;
	unsigned int ssl:1;

	unsigned int accepted:1;
};

typedef void
master_service_connection_callback_t(struct master_service_connection *conn);

extern struct master_service *master_service;

const char *master_service_getopt_string(void);

/* Start service initialization. */
struct master_service *
master_service_init(const char *name, enum master_service_flags flags,
		    int *argc, char **argv[], const char *getopt_str);
/* Call getopt() and handle internal parameters. Return values are the same as
   getopt()'s. */
int master_getopt(struct master_service *service);
/* Parser command line option. Returns TRUE if processed. */
bool master_service_parse_option(struct master_service *service,
				 int opt, const char *arg);
/* Finish service initialization. The caller should drop privileges
   before calling this. */
void master_service_init_finish(struct master_service *service);

/* Clean environment from everything except the ones listed in
   DOVECOT_PRESERVE_ENVS environment. */
void master_service_env_clean(void);

/* Initialize logging. */
void master_service_init_log(struct master_service *service,
			     const char *prefix);

/* If set, die immediately when connection to master is lost.
   Normally all existing clients are handled first. */
void master_service_set_die_with_master(struct master_service *service,
					bool set);
/* Call the given when master connection dies and die_with_master is TRUE.
   The callback is expected to shut down the service somewhat soon or it's
   done forcibly. If NULL, the service is stopped immediately. */
void master_service_set_die_callback(struct master_service *service,
				     void (*callback)(void));
/* Call the given callback when there are no available connections and master
   has indicated that it can't create any more processes to handle requests.
   The callback could decide to kill one of the existing connections. */
void master_service_set_avail_overflow_callback(struct master_service *service,
						void (*callback)(void));

/* Set maximum number of clients we can handle. Default is given by master. */
void master_service_set_client_limit(struct master_service *service,
				     unsigned int client_limit);
/* Returns the maximum number of clients we can handle. */
unsigned int master_service_get_client_limit(struct master_service *service);

/* Set maximum number of client connections we will handle before shutting
   down. */
void master_service_set_service_count(struct master_service *service,
				      unsigned int count);
/* Returns the number of client connections we will handle before shutting
   down. The value is decreased only after connection has been closed. */
unsigned int master_service_get_service_count(struct master_service *service);
/* Return the number of listener sockets. */
unsigned int master_service_get_socket_count(struct master_service *service);

/* Returns configuration file path. */
const char *master_service_get_config_path(struct master_service *service);
/* Returns PACKAGE_VERSION or NULL if version_ignore=yes. This function is
   useful mostly as parameter to module_dir_load(). */
const char *master_service_get_version_string(struct master_service *service);
/* Returns name of the service, as given in name parameter to _init(). */
const char *master_service_get_name(struct master_service *service);

/* Start the service. Blocks until finished */
void master_service_run(struct master_service *service,
			master_service_connection_callback_t *callback);
/* Stop a running service. */
void master_service_stop(struct master_service *service);
/* Stop once we're done serving existing new connections, but don't accept
   any new ones. */
void master_service_stop_new_connections(struct master_service *service);
/* Returns TRUE if we've received a SIGINT/SIGTERM and we've decided to stop. */
bool master_service_is_killed(struct master_service *service);

/* Send command to anvil process, if we have fd to it. */
void master_service_anvil_send(struct master_service *service, const char *cmd);
/* Call to accept the client connection. Otherwise the connection is closed. */
void master_service_client_connection_accept(struct master_service_connection *conn);
/* Call whenever a client connection is destroyed. */
void master_service_client_connection_destroyed(struct master_service *service);

/* Deinitialize the service. */
void master_service_deinit(struct master_service **service);

/* Returns TRUE if line contains compatible service name and major version.
   The line is expected to be in format:
   VERSION <tab> service_name <tab> major version <tab> minor version */
bool version_string_verify(const char *line, const char *service_name,
			   unsigned major_version);

#endif