File:  [parser3project] / parser3 / src / main / pa_stylesheet_manager.C
Revision 1.16.2.7: download - view: text, annotated - select for diffs - revision graph
Thu Mar 6 16:15:25 2003 UTC (23 years, 4 months ago) by paf
Diff to: branchpoint 1.16: preferred, unified
xnode.C compiled

/** @file
	Parser: sql driver manager implementation.

	Copyright (c) 2001-2003 ArtLebedev Group (http://www.artlebedev.com)
	Author: Alexandr Petrosian <paf@design.ru> (http://paf.design.ru)
*/
#include "pa_config_includes.h"
#ifdef XML

static const char* IDENT_STYLESHEET_MANAGER_C="$Date: 2003/03/06 16:15:25 $";

#include "pa_stylesheet_manager.h"
#include "pa_stylesheet_connection.h"
#include "pa_exception.h"
#include "pa_common.h"
#include "pa_threads.h"
#include "pa_stack.h"
#include "pa_vhash.h"
#include "pa_vtable.h"

// globals

Stylesheet_manager stylesheet_manager;

// consts

const time_t SECOND=1;
const time_t EXPIRE_UNUSED_CONNECTION_SECONDS=5*60;
const time_t CHECK_EXPIRED_CONNECTION_SECONDS=EXPIRE_UNUSED_CONNECTION_SECONDS*2;

// helpers

static void expire_connection(Stylesheet_connection& connection, time_t older_dies) {
	if(connection.connected() && connection.expired(older_dies))
		connection.disconnect();
}
static void expire_connections(
							   Stylesheet_manager::connection_cache_type::key_type /*key*/, 
							   Stylesheet_manager::connection_cache_type::value_type stack, 
							   time_t older_dies) {
	for(int i=0; i<=stack->top_index(); i++)
		expire_connection(*stack->get(i), older_dies);
}

// Stylesheet_manager

Stylesheet_manager::Stylesheet_manager(): prev_expiration_pass_time(0) {

	cache_managers.put(StringPtr(new String("stylesheet")), this);
}

Stylesheet_manager::~Stylesheet_manager() {
	connection_cache.for_each(expire_connections, time(0)+SECOND/*=in future=expire all*/);
}

Stylesheet_connectionPtr Stylesheet_manager::get_connection(StringPtr file_spec) {
	Stylesheet_connectionPtr result=get_connection_from_cache(file_spec);
	if(!result)
		result=Stylesheet_connectionPtr(new Stylesheet_connection(file_spec));
	return result;
}

void Stylesheet_manager::close_connection(StringPtr file_spec, 
										  Stylesheet_connection& connection) {
	put_connection_to_cache(file_spec, Stylesheet_connectionPtr(&connection));
}

// stylesheet cache
/// @todo get rid of memory spending Stack [zeros deep inside got accumulated]
Stylesheet_connectionPtr Stylesheet_manager::get_connection_from_cache(StringPtr file_spec) { 
	SYNCHRONIZED;

	if(connection_cache_type::value_type connections=connection_cache.get(file_spec))
		while(connections->top_index()>=0) { // there are cached stylesheets to that 'file_spec'
			Stylesheet_connectionPtr result=connections->pop();
			if(result->connected()) // not expired?
				return result;
		}

	return Stylesheet_connectionPtr(0);
}

void Stylesheet_manager::put_connection_to_cache(StringPtr file_spec, 
												 Stylesheet_connectionPtr connection) { 
	SYNCHRONIZED;

	connection_cache_type::value_type connections=connection_cache.get(file_spec);
	if(!connections) { // there are no cached stylesheets to that 'file_spec' yet?
		connections=connection_cache_type::value_type(new connection_cache_type::value_type::element_type);
		connection_cache.put(file_spec, connections);
	}	
	connections->push(connection);
}

void Stylesheet_manager::maybe_expire_cache() {
	time_t now=time(0);

	if(prev_expiration_pass_time<now-CHECK_EXPIRED_CONNECTION_SECONDS) {
		connection_cache.for_each(expire_connections, now-EXPIRE_UNUSED_CONNECTION_SECONDS);

		prev_expiration_pass_time=now;
	}
}
/*
static void add_connection_to_status_cache_table(Array::Item *value, void *info) {
	Stylesheet_connection& connection=*static_cast<Stylesheet_connection *>(value);
	Table& table=*static_cast<Table *>(info);

	if(connection.connected()) {
		Pool& pool=table.pool();
		Array& row=*new(pool) Array(pool);

		// file
		row+=&connection.file_spec();
		// time
		time_t time_stamp=connection.get_time_used();
		row+=new(pool) String(pool, pool.copy(ctime(&time_stamp)));

		table+=&row;
	}
}
static void add_connections_to_status_cache_table(const Hash::Key& key, Hash::Val *value, void *info) {
	Stack& stack=*static_cast<Stack *>(value);
	Array_iter iter(stack);
	for(int countdown=stack.top_index(); countdown-->=0; )
		add_connection_to_status_cache_table(iter.next(), info);
}
*/
ValuePtr Stylesheet_manager::get_status(Pool& pool, StringPtr source) {
	VHashPtr result(new VHash);
/*
	// cache
	{
		Array& columns=*new(pool) Array(pool);
		columns+=new(pool) String(pool, "file");
		columns+=new(pool) String(pool, "time");
		Table& table=*new(pool) Table(pool, 0, &columns, connection_cache.size());

		connection_cache.for_each(add_connections_to_status_cache_table, &table);

		result.hash(source).put(*new(pool) String(pool, "cache"), new(pool) VTable(pool, &table));
	}
*/
	return result;
}

#endif

E-mail: