/*
 * Sendpacket.c 
 *
 * An invaluable addition to your Amiga.lib file. This code sends a packet the
 * given message port. This makes working around DOS lots easier. 
 *
 * Note, I didn't write this, those wonderful folks at CBM did. I do suggest
 * however that you may wish to add it to Amiga.Lib, to do so, compile it and
 * say 'oml lib:amiga.lib -r sendpacket.o' 
 */

#include <exec/types.h>
#include <exec/ports.h>
#include <exec/memory.h>
#include <libraries/dos.h>
#include <libraries/dosextens.h>

/*
 * Function - SendPacket written by Phil Lindsay, Carolyn Scheppner, and Andy
 * Finkel. This function will send a packet of the given type to the Message
 * Port supplied. 
 */

long
SendPacket(pid, action, args, nargs)
struct MsgPort	*pid;	/* process indentifier ... (handler's message port ) */
long		action,	/* packet type ... (what you want handler to do )   */
		args[],	/* a pointer to an argument list */
		nargs;	/* number of arguments in list  */
{
	struct MsgPort *replyport, *CreatePort();
	struct StandardPacket *packet;
	extern char *AllocMem();
	long count, *pargs, res1;

	replyport = CreatePort(NULL, 0L);
	if (!replyport)
		return (0);

	/* Allocate space for a packet, make it public and clear it */
	packet = (struct StandardPacket *)
		AllocMem((long) sizeof(struct StandardPacket),
			MEMF_PUBLIC | MEMF_CLEAR);
	if (!packet) {
		DeletePort(replyport);
		return (0);
	}
	packet->sp_Msg.mn_Node.ln_Name = (char *) &(packet->sp_Pkt);
	packet->sp_Pkt.dp_Link = &(packet->sp_Msg);
	packet->sp_Pkt.dp_Port = replyport;
	packet->sp_Pkt.dp_Type = action;

	/* copy the args into the packet */
	pargs = &(packet->sp_Pkt.dp_Arg1);	/* address of first argument */
	for (count = 0; count < nargs; count++)
		pargs[count] = args[count];

	PutMsg(pid, packet);	/* send packet */

	WaitPort(replyport);
	GetMsg(replyport);

	res1 = packet->sp_Pkt.dp_Res1;

	FreeMem(packet, (long) sizeof(struct StandardPacket));
	DeletePort(replyport);

	return (res1);
}