rom/exec/putmsg.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Send a message to a port.
   6     Lang: english
   7 */
   8 #include "exec_intern.h"
   9 #include <aros/libcall.h>
  10 #include <exec/ports.h>
  11 #include <proto/exec.h>
  12
  13 /*****************************************************************************
  14
  15     NAME */
  16
  17         AROS_LH2(void, PutMsg,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(struct MsgPort *, port,    A0),
  21         AROS_LHA(struct Message *, message, A1),
  22
  23 /*  LOCATION */
  24         struct ExecBase *, SysBase, 61, Exec)
  25
  26 /*  FUNCTION
  27         Sends a message to a given message port. Messages are not copied
  28         from one task to another but must lie in shared memory instead.
  29         Therefore the owner of the message may generally not reuse it before
  30         it is returned. But this depends on the two tasks sharing the message.
  31
  32     INPUTS
  33         port    - Pointer to messageport.
  34         message - Pointer to message.
  35
  36     RESULT
  37
  38     NOTES
  39         It is legal to send a message from within interrupts.
  40
  41         Messages may either trigger a signal at the owner of the messageport
  42         or raise a software interrupt, depending on port->mp_Flags&PF_ACTION.
  43
  44     EXAMPLE
  45
  46     BUGS
  47
  48     SEE ALSO
  49         WaitPort(), GetMsg()
  50
  51     INTERNALS
  52
  53 ******************************************************************************/
  54 {
  55     AROS_LIBFUNC_INIT
  56     ASSERT_VALID_PTR(message);
  57     ASSERT_VALID_PTR(port);
  58
  59     /*
  60         Messages may be sent from interrupts. Therefore the message list
  61         of the message port must be protected with Disable().
  62     */
  63     Disable();
  64
  65     /* Set the node type to NT_MESSAGE == sent message. */
  66     message->mn_Node.ln_Type=NT_MESSAGE;
  67
  68     /* Add it to the message list. */
  69     AddTail(&port->mp_MsgList,&message->mn_Node);
  70
  71     if(port->mp_SigTask)
  72     {
  73         ASSERT_VALID_PTR(port->mp_SigTask);
  74
  75         /* And trigger the action. */
  76         switch(port->mp_Flags & PF_ACTION)
  77         {
  78             case PA_SIGNAL:
  79                 /* Send the signal */
  80                 Signal((struct Task *)port->mp_SigTask,1<<port->mp_SigBit);
  81                 break;
  82
  83             case PA_SOFTINT:
  84                 /* Raise a software interrupt */
  85                 Cause((struct Interrupt *)port->mp_SoftInt);
  86                 break;
  87
  88             case PA_IGNORE:
  89                 /* Do nothing. */
  90                 break;
  91         }
  92     }
  93
  94     /* All done. */
  95     Enable();
  96     AROS_LIBFUNC_EXIT
  97 } /* PutMsg() */
  98