/* -------------------------------------------------------------------------

*

* restgres.c

* Sample background worker code that demonstrates various coding

* patterns: establishing a database connection; starting and committing

* transactions; using GUC variables, and heeding SIGHUP to reread

* the configuration file; reporting to pg_stat_activity; using the

* process latch to sleep and exit in case of postmaster death.

*

* This code connects to a database, creates a schema and table, and summarizes

* the numbers contained therein. To see it working, insert an initial value

* with "total" type and some initial value; then insert some other rows with

* "delta" type. Delta rows will be deleted by this worker and their values

* aggregated into the total.

*

* Copyright (C) 2013, PostgreSQL Global Development Group

*

* IDENTIFICATION

* contrib/restgres/restgres.c

*

* -------------------------------------------------------------------------

*/

#define sigjmp_buf jmp_buf

#include "setjmp.h"

#include "unistd.h"

#include "postgres.h"

/* These are always necessary for a bgworker */

#include "miscadmin.h"

#include "storage/ipc.h"

#include "storage/latch.h"

#include "storage/lwlock.h"

#include "storage/proc.h"

#include "storage/shmem.h"

/* these headers are used by this particular worker's code */

#include "access/xact.h"

#include "executor/spi.h"

#include "fmgr.h"

#include "lib/stringinfo.h"

#include "pgstat.h"

#include "utils/builtins.h"

#include "utils/snapmgr.h"

#include "utils/memutils.h"

#include "tcop/utility.h"

#include "libpq/libpq.h"

#include "libpq/crypt.h"

#include "libpq/ip.h"

#include "postmaster/postmaster.h"

#include "postmaster/bgworker.h"

#include "catalog/pg_database.h"

#include <event2/event.h>

#include <event2/http.h>

#include <event2/buffer.h>

#include <event2/listener.h>

#include <event2/util.h>

#include <event2/keyvalq_struct.h>

#include <event2/bufferevent.h>

#include <sys/queue.h>

#include "bgwutil.h"

#include "util.h"

#include "backend.h"

#include "master.h"

PG_MODULE_MAGIC

;

void

_PG_init(void);

/*

* Entrypoint of this module.

*

* We register more than one worker process here, to demonstrate how that can

* be done.

*/

void _PG_init(void)

{

struct BackgroundWorker worker = { "restgres master" };

/* get the configuration */

DefineCustomStringVariable("http.listen_addresses",

"Addresses to listen on; see PostgreSQL listen_addresses",

NULL, &restgres_listen_addresses, "*", PGC_SIGHUP, 0,

NULL,

NULL,

NULL);

DefineCustomIntVariable("http.port",

"Port to listen on (default: any available port)",

NULL, &restgres_listen_port, restgres_listen_port, 0, 32768,

PGC_SIGHUP, 0,

NULL,

NULL,

NULL);

DefineCustomIntVariable("http.max_connections",

"Maximum number of connections to serve at once (additional connections will have to wait or be rejected)",

NULL, &restgres_max_connections, 100, 0,

INT_MAX, PGC_SIGHUP, 0,

NULL,

NULL,

NULL);

DefineCustomIntVariable("http.max_concurrency",

"Maximum number of connections to serve at once (additional connections will have to wait or be rejected)",

NULL, &restgres_max_concurrency, 100, 0,

INT_MAX, PGC_SIGHUP, 0,

NULL,

NULL,

NULL);

/* set up common data for all our workers */

worker.bgw_flags = BGWORKER_SHMEM_ACCESS

| BGWORKER_BACKEND_DATABASE_CONNECTION;

worker.bgw_restart_time = BGW_DEFAULT_RESTART_INTERVAL;

worker.bgw_start_time = BgWorkerStart_RecoveryFinished;

worker.bgw_main = restgres_main;

worker.bgw_notify_pid = 0;

RegisterBackgroundWorker(&worker);

}