Amiga ISO Collection/AmigaUtilCD1.iso/Editor/Edge1721.DMS/Edge1721.adf/ExtraStuff/Edge_SasC.lha/echohandler/EchoHandler.C

C/C++ Source or Header | 1993-11-09 | 4.7 KB | 204 lines

/* Echo Handler V1.2
** ©1991 Henrik Nordström
** Ängsvägen 1
** 756 45 Uppsala
** Sweden
**
** Fully public domain, and truly a real hack...
** Use it in any way you like, but don't blame me if it doesn't work.
** This little code needs AmigaDOS 2.0-> to work without modification
** if you like, write your own packet-handling functions and compile it
** to work whith 1.1->
** functions needed in 2.0 is: WaitPkt, and ReplyPkt
**
** Example for use:
** .>dir >ECHO:dirdump ram: all
** .>list >ECHO:ram:listdump dh0:
**
** compiled with SAS/C 5.10b
**
** lc -v -O EchoHandler.c
** blink EchoHandler.o
** copy EchoHandler L:
**
** Mount list entry to use ECHO:
** ECHO:
**     Handler = l:EchoHandler
**     Stacksize = 3000
**     Priority = 5
**     GlobVec = -1
** #
**
*/

#include <string.h>

#include <dos/dos.h>
#include <dos/dosextens.h>
#include <dos/filehandler.h>

#include <proto/exec.h>
#include <proto/dos.h>

struct Library *SysBase;
struct DosLibrary *DOSBase;

struct filedata
{
  BPTR confh;
  BPTR filefh;
};

void __saveds
start (void)
{
  struct DosPacket *pkt;
  struct DeviceNode *node;
  struct Process *myproc;
  struct Process *theirproc;
  struct MsgPort *myport;
  struct FileHandle *fh;
  struct filedata *fd;
  int die = FALSE;
  LONG type;
  LONG arg1;
  LONG arg2;
  LONG arg3;
  int opencount = 0;
  char *name;
  BPTR confh;
  BPTR filefh;
  char *data;
  int len;
  BPTR oldcurrentdir;
  LONG filemode;
  LONG filepos;

  SysBase = *((struct Library **) 4L);
  myproc = (struct Process *) FindTask (NULL);
  myport = &myproc->pr_MsgPort;

  DOSBase = (struct DosLibrary *) OpenLibrary ("dos.library", 36);
  if (DOSBase == NULL)
    return;

  pkt = WaitPkt ();
  node = BADDR (pkt->dp_Arg3);

  /*
   * Install process if everything OK and stay resident forever! * (or
   * until killed whith ACTION_DIE) )
   */
  node->dn_Task = myport;
  ReplyPkt (pkt, DOSTRUE, pkt->dp_Arg2);

  do
    {
      pkt = WaitPkt ();
      type = pkt->dp_Type;
      arg1 = pkt->dp_Arg1;
      arg2 = pkt->dp_Arg2;
      arg3 = pkt->dp_Arg3;
      fd = (struct filedata *) arg1;
      switch (type)
    {
    case ACTION_FINDINPUT:
      filemode=MODE_OLDFILE;
      goto OPEN_FILE;
    case ACTION_FINDOUTPUT:
      filemode=MODE_NEWFILE;
      goto OPEN_FILE;
    case ACTION_FINDUPDATE:
      filemode=MODE_READWRITE;
      goto OPEN_FILE;
    OPEN_FILE:
      fh = (struct FileHandle *) BADDR (arg1);
      name = (char *) BADDR (arg3) + 1;
      /* Strip ECHO: from filename */
      while (*name && *name != ':')
        name++;
      if (*name == ':')
        name++;

      /*
       * Find the two output streams
       *  1: current output of calling process
       *  2: filename relative to calling process CurrentDir
       */
      theirproc = (struct Process *) pkt->dp_Port->mp_SigTask;
      oldcurrentdir = CurrentDir (theirproc->pr_CurrentDir);
      if(theirproc->pr_CLI)
        confh = ((struct CommandLineInterface *)BADDR(theirproc->pr_CLI))->cli_CurrentOutput;
      else
        confh = theirproc->pr_COS;
      filefh = Open (name, filemode);
      CurrentDir (oldcurrentdir);
      if (!filefh)
        {
          ReplyPkt (pkt, DOSFALSE, IoErr ());
          break;
        }
      fd = (struct filedata *) AllocMem (sizeof (*fd), 0);
      if (fd == NULL)
        {
          Close (filefh);
          ReplyPkt (pkt, DOSFALSE, ERROR_NO_FREE_STORE);
          break;
        }
      /* Everything OK! fill in datastructure and reply. */
      fd->confh = confh;
      fd->filefh = filefh;
      /* real strange names in 2.02... probably better names in include 2.04 */
      fh->fh_Port = (struct MsgPort *)(-1L); /* Interactive */
      fh->fh_Type = myport;  /* Message port */
      fh->fh_Arg1 = (LONG) fd; /* File data, passed as ARG1 to all functions */
      ReplyPkt (pkt, DOSTRUE, 0);
      opencount++;
      break;
    case ACTION_WRITE:
      data = (char *) arg2;
      len = arg3;
      if (fd->confh)
        Write (fd->confh, data, len);
      if (fd->filefh)
        Write (fd->filefh, data, len);
      ReplyPkt (pkt, len, 0);
      break;
    case ACTION_READ:
      data = (char *) arg2;
      len = arg3;
      if (fd->filefh)
        len=Read (fd->filefh, data, len);
      if(len<0)
        ReplyPkt(pkt, len, IoErr());
      if (fd->filefh && len>0)
        Write (fd->confh, data, len);
      ReplyPkt (pkt, len, 0);
      break;
    case ACTION_SEEK:
      filepos=Seek(fd->filefh,arg2,arg3);
      ReplyPkt(pkt,filepos,IoErr());
      break;
    case ACTION_END:
      if (fd->filefh)
        Close (fd->filefh);
      FreeMem ((APTR) fd, sizeof (*fd));
      ReplyPkt (pkt, DOSTRUE, 0);
      opencount--;
      break;
    case ACTION_DIE:
      /* Action_KillHandler */
      die = TRUE;
      node->dn_Task = NULL;
      ReplyPkt (pkt, DOSTRUE, 0);
      break;
    default:
      /* Action_CantHandleThis B-( */
      ReplyPkt (pkt, DOSFALSE, ERROR_ACTION_NOT_KNOWN);
      break;
    }
  } while (!die || opencount > 0);

  CloseLibrary ((struct Library *) DOSBase);
}