Software Público Brasileiro

/*
 * "Software pw3270, desenvolvido com base nos códigos fontes do WC3270  e X3270
 * (Paul Mattes Paul.Mattes@usa.net), de emulação de terminal 3270 para acesso a
 * aplicativos mainframe. Registro no INPI sob o nome G3270.
 *
 * Copyright (C) <2008> <Banco do Brasil S.A.>
 *
 * Este programa é software livre. Você pode redistribuí-lo e/ou modificá-lo sob
 * os termos da GPL v.2 - Licença Pública Geral  GNU,  conforme  publicado  pela
 * Free Software Foundation.
 *
 * Este programa é distribuído na expectativa de  ser  útil,  mas  SEM  QUALQUER
 * GARANTIA; sem mesmo a garantia implícita de COMERCIALIZAÇÃO ou  de  ADEQUAÇÃO
 * A QUALQUER PROPÓSITO EM PARTICULAR. Consulte a Licença Pública Geral GNU para
 * obter mais detalhes.
 *
 * Você deve ter recebido uma cópia da Licença Pública Geral GNU junto com este
 * programa; se não, escreva para a Free Software Foundation, Inc., 51 Franklin
 * St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Este programa está nomeado como iocallback.c e possui - linhas de código.
 *
 * Contatos:
 *
 * perry.werneck@gmail.com	(Alexandre Perry de Souza Werneck)
 * erico.mendonca@gmail.com	(Erico Mascarenhas Mendonça)
 * licinio@bb.com.br		(Licínio Luis Branco)
 * kraucer@bb.com.br		(Kraucer Fernandes Mazuco)
 *
 */

#if defined(_WIN32) /*[*/
	#include <windows.h>
#elif defined(__APPLE__)
	#include <poll.h>
	#include <string.h>
#else
	#include <poll.h>
	#include <string.h>
#endif /*]*/

#include <stdio.h>
#include <glib.h>
#include "daemon.h"

static int 				  static_CallAndWait(int(*callback)(H3270 *session, void *), H3270 *session, void *parm);
static void				  static_RemoveSource(void *id);

static void 			* static_AddInput(int source, H3270 *session, void (*fn)(H3270 *session));
static void 			* static_AddExcept(int source, H3270 *session, void (*fn)(H3270 *session));

static void 			* static_AddTimeOut(unsigned long interval_ms, H3270 *session, void (*proc)(H3270 *session));
static void 			  static_RemoveTimeOut(void * timer);
static int				  static_Sleep(H3270 *hSession, int seconds);
static int 				  static_RunPendingEvents(H3270 *hSession, int wait);

static gboolean 		IO_prepare(GSource *source, gint *timeout);
static gboolean 		IO_check(GSource *source);
static gboolean 		IO_dispatch(GSource *source, GSourceFunc callback, gpointer user_data);
static void 			IO_finalize(GSource *source); /* Can be NULL */
static gboolean			IO_closure(gpointer data);

/*---[ Structs ]-------------------------------------------------------------------------------------------*/

 typedef struct _IO_Source
 {
	GSource gsrc;
	GPollFD	poll;
#if defined(_WIN32)
	HANDLE	source;
#else
	int		source;
#endif // _WIN32
	void	(*fn)(H3270 *session);
	H3270 	*session;
 } IO_Source;

 typedef struct _timer
 {
	unsigned char remove;
	void	(*fn)(H3270 *session);
	H3270 	*session;
 } TIMER;

 static GSourceFuncs IOSources =
 {
        IO_prepare,
        IO_check,
        IO_dispatch,
        IO_finalize,
        IO_closure,
        NULL
 };

/*---[ Implement ]-----------------------------------------------------------------------------------------*/

#ifdef _WIN32
static void * AddSource(HANDLE source, H3270 *session, gushort events, void (*fn)(H3270 *session))
#else
static void * AddSource(int source, H3270 *session, gushort events, void (*fn)(H3270 *session))
#endif // _WIN32
{
	IO_Source *src = (IO_Source *) g_source_new(&IOSources,sizeof(IO_Source));

	src->source			= source;
	src->fn				= fn;
	src->poll.fd		= (int) source;
	src->poll.events	= events;
	src->session		= session;

	g_source_attach((GSource *) src,NULL);
	g_source_add_poll((GSource *) src,&src->poll);

	return src;
}

#ifdef _WIN32
static void * static_AddInput(HANDLE source, H3270 *session, void (*fn)(H3270 *session))
#else
static void * static_AddInput(int source, H3270 *session, void (*fn)(H3270 *session))
#endif // _WIN32
{
	return AddSource(source,session,G_IO_IN|G_IO_HUP|G_IO_ERR,fn);
}

static void static_RemoveSource(void *id)
{
	if(id)
		g_source_destroy((GSource *) id);
}

#if defined(_WIN32)
static void * static_AddExcept(HANDLE source, H3270 *session, void (*fn)(H3270 *session))
{
	return 0;
}
#else
static void * static_AddExcept(int source, H3270 *session, void (*fn)(H3270 *session))
{
	return AddSource(source,session,G_IO_HUP|G_IO_ERR,fn);
}
#endif // _WIN32

static gboolean do_timer(TIMER *t)
{
	if(!t->remove)
		t->fn(t->session);
	return FALSE;
}

static void * static_AddTimeOut(unsigned long interval, H3270 *session, void (*proc)(H3270 *session))
{
	TIMER *t = g_malloc0(sizeof(TIMER));

	t->fn		= proc;
	t->session	= session;

	g_timeout_add_full(G_PRIORITY_DEFAULT, (guint) interval, (GSourceFunc) do_timer, t, g_free);

	return t;
}

static void static_RemoveTimeOut(void * timer)
{
	((TIMER *) timer)->remove++;
}

static gboolean IO_prepare(GSource *source, gint *timeout)
{
	/*
 	 * Called before all the file descriptors are polled.
	 * If the source can determine that it is ready here
	 * (without waiting for the results of the poll() call)
	 * it should return TRUE.
	 *
	 * It can also return a timeout_ value which should be the maximum
	 * timeout (in milliseconds) which should be passed to the poll() call.
	 * The actual timeout used will be -1 if all sources returned -1,
	 * or it will be the minimum of all the timeout_ values
	 * returned which were >= 0.
	 *
	 */
	return 0;
}

static gboolean IO_check(GSource *source)
{
	/*
 	 * Called after all the file descriptors are polled.
 	 * The source should return TRUE if it is ready to be dispatched.
	 * Note that some time may have passed since the previous prepare
	 * function was called, so the source should be checked again here.
	 *
	 */
#if defined(_WIN32) /*[*/

	if(WaitForSingleObject(((IO_Source *) source)->source,0) == WAIT_OBJECT_0)
		return TRUE;

#else /*][*/

	struct pollfd fds;

	memset(&fds,0,sizeof(fds));

	fds.fd     = ((IO_Source *) source)->poll.fd;
    fds.events = ((IO_Source *) source)->poll.events;

	if(poll(&fds,1,0) > 0)
		return TRUE;

#endif /*]*/

	return FALSE;
}

static gboolean IO_dispatch(GSource *source, GSourceFunc callback, gpointer user_data)
{
	/*
	 * Called to dispatch the event source,
	 * after it has returned TRUE in either its prepare or its check function.
	 * The dispatch function is passed in a callback function and data.
	 * The callback function may be NULL if the source was never connected
	 * to a callback using g_source_set_callback(). The dispatch function
	 * should call the callback function with user_data and whatever additional
	 * parameters are needed for this type of event source.
	 */
	((IO_Source *) source)->fn(((IO_Source *) source)->session);
	return TRUE;
}

static void IO_finalize(GSource *source)
{

}

static gboolean IO_closure(gpointer data)
{
	return 0;
}

struct bgParameter
{
	gboolean	running;
	gboolean	timer;
	H3270		*session;
	int			rc;
	int(*callback)(H3270 *session, void *);
	void		*parm;

};

gpointer BgCall(struct bgParameter *p)
{
//	trace("%s starts",__FUNCTION__);
	p->rc = p->callback(p->session, p->parm);
	p->running = FALSE;
//	trace("%s ends",__FUNCTION__);
	return 0;
}

static gboolean wait_for_thread(struct bgParameter *p)
{
	if(!p->running)
	{
		p->timer = 0;
		return FALSE;
	}
	return TRUE;
}

static int static_CallAndWait(int(*callback)(H3270 *session, void *), H3270 *session, void *parm)
{
	struct bgParameter	  p			= { TRUE, TRUE, session, -1, callback, parm };
	GThread				* thread;

//	trace("Starting auxiliary thread for callback %p",callback);

	p.running	= TRUE;
	p.timer 	= TRUE;

    thread = g_thread_create( (GThreadFunc) BgCall, &p, 0, NULL);

    if(!thread)
    {
    	g_error("Can't start background thread");
    	return -1;
    }

	g_timeout_add(50,(GSourceFunc) wait_for_thread,(gpointer) &p);

	while(p.timer)
		g_main_context_iteration(g_main_loop_get_context(main_loop),TRUE);

    return p.rc;
}

static int static_Sleep(H3270 *hSession, int seconds)
{
	time_t end = time(0) + seconds;

	while(time(0) < end)
		g_main_iteration(TRUE);

	return 0;
}

static int static_RunPendingEvents(H3270 *hSession, int wait)
{
	GMainContext *context = g_main_loop_get_context(main_loop);
	int rc = 0;
	while(g_main_context_pending(context))
	{
		rc = 1;
		g_main_context_iteration(context,FALSE);
	}

	if(wait)
		g_main_context_iteration(context,TRUE);

	return rc;
}

static void beep(H3270 *session)
{
}

void pw3270_dbus_register_io_handlers(void)
{
	static const struct lib3270_callbacks hdl =
	{
		sizeof(struct lib3270_callbacks),

		static_AddTimeOut,
		static_RemoveTimeOut,

		static_AddInput,
		static_RemoveSource,

		static_AddExcept,

#ifdef G_THREADS_ENABLED
		static_CallAndWait,
#else
		NULL,
#endif

		static_Sleep,
		static_RunPendingEvents,
		beep

	};

	#error Need rewrite

	if(lib3270_register_handlers(&hdl))
	{
		g_error("%s","Can't set lib3270 I/O handlers");
	}

}