📄 pic.c
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/*************************************************************************/
/* */
/* Copyright Mentor Graphics Corporation 2004 */
/* All Rights Reserved. */
/* */
/* THIS WORK CONTAINS TRADE SECRET AND PROPRIETARY INFORMATION WHICH IS */
/* THE PROPERTY OF MENTOR GRAPHICS CORPORATION OR ITS LICENSORS AND IS */
/* SUBJECT TO LICENSE TERMS. */
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/* FILE NAME VERSION */
/* */
/* pic.c Nucleus PLUS 1.15 */
/* */
/* COMPONENT */
/* */
/* PI - Pipe Management */
/* */
/* DESCRIPTION */
/* */
/* This file contains the core routines for the pipe management */
/* component. */
/* */
/* DATA STRUCTURES */
/* */
/* None */
/* */
/* FUNCTIONS */
/* */
/* PIC_Create_Pipe Create a message pipe */
/* PIC_Delete_Pipe Delete a message pipe */
/* PIC_Send_To_Pipe Send message to a pipe */
/* PIC_Receive_From_Pipe Receive a message from pipe */
/* PIC_Cleanup Cleanup on timeout or a */
/* terminate condition */
/* */
/* DEPENDENCIES */
/* */
/* cs_extr.h Common Service functions */
/* tc_extr.h Thread Control functions */
/* pi_extr.h Pipe functions */
/* hi_extr.h History functions */
/* */
/*************************************************************************/
#define NU_SOURCE_FILE
#include "plus/inc/cs_extr.h" /* Common service functions */
#include "plus/inc/tc_extr.h" /* Thread control functions */
#include "plus/inc/pi_extr.h" /* Pipe functions */
#include "plus/inc/hi_extr.h" /* History functions */
/* Define external inner-component global data references. */
extern CS_NODE *PID_Created_Pipes_List;
extern UNSIGNED PID_Total_Pipes;
extern TC_PROTECT PID_List_Protect;
/* Define internal component function prototypes. */
VOID PIC_Cleanup(VOID *information);
/*************************************************************************/
/* */
/* FUNCTION */
/* */
/* PIC_Create_Pipe */
/* */
/* DESCRIPTION */
/* */
/* This function creates a pipe and then places it on the list */
/* of created pipes. */
/* */
/* CALLED BY */
/* */
/* Application */
/* PICE_Create_Pipe Error checking shell */
/* */
/* CALLS */
/* */
/* CSC_Place_On_List Add to node to linked-list */
/* [HIC_Make_History_Entry] Make entry in history log */
/* [TCT_Check_Stack] Stack checking function */
/* TCT_Protect Data structure protect */
/* TCT_Unprotect Un-protect data structure */
/* */
/* INPUTS */
/* */
/* pipe_ptr Pipe control block pointer */
/* name Pipe name */
/* start_address Starting address of actual */
/* pipe area */
/* pipe_size Total size of pipe in bytes */
/* message_type Type of message supported by */
/* the pipe (fixed/variable) */
/* message_size Size of message. Variable */
/* message-length pipes, this */
/* represents the maximum size*/
/* suspend_type Suspension type */
/* */
/* OUTPUTS */
/* */
/* NU_SUCCESS */
/* */
/*************************************************************************/
STATUS PIC_Create_Pipe(NU_PIPE *pipe_ptr, CHAR *name,
VOID *start_address, UNSIGNED pipe_size,
OPTION message_type, UNSIGNED message_size,
OPTION suspend_type)
{
R1 PI_PCB *pipe; /* Pipe control block ptr */
INT i; /* Working index variable */
NU_SUPERV_USER_VARIABLES
/* Switch to supervisor mode */
NU_SUPERVISOR_MODE();
/* Move input pipe pointer into internal pointer. */
pipe = (PI_PCB *) pipe_ptr;
#ifdef NU_ENABLE_STACK_CHECK
/* Call stack checking function to check for an overflow condition. */
TCT_Check_Stack();
#endif
#ifdef NU_ENABLE_HISTORY
/* Make an entry that corresponds to this function in the system history
log. */
HIC_Make_History_Entry(NU_CREATE_PIPE_ID, (UNSIGNED) pipe,
(UNSIGNED) name, (UNSIGNED) start_address);
#endif
/* First, clear the pipe ID just in case it is an old pipe
Control Block. */
pipe -> pi_id = 0;
/* Fill in the pipe name. */
for (i = 0; i < NU_MAX_NAME; i++)
pipe -> pi_name[i] = name[i];
/* Setup the pipe suspension type. */
if (suspend_type == NU_FIFO)
/* FIFO suspension is selected, setup the flag accordingly. */
pipe -> pi_fifo_suspend = NU_TRUE;
else
/* Priority suspension is selected. */
pipe -> pi_fifo_suspend = NU_FALSE;
/* Setup the pipe message type. */
if (message_type == NU_FIXED_SIZE)
/* Fixed-size messages are required. */
pipe -> pi_fixed_size = NU_TRUE;
else
/* Variable-size messages are required. */
pipe -> pi_fixed_size = NU_FALSE;
/* Setup the message size. */
pipe -> pi_message_size = message_size;
/* Clear the messages counter. */
pipe -> pi_messages = 0;
/* Setup the actual pipe pointers. */
pipe -> pi_pipe_size = pipe_size;
/* Determine if the pipe's size needs to be adjusted. */
if (pipe -> pi_fixed_size)
/* The size of a fixed-size message pipe must be an even multiple of
the actual message size. */
pipe_size = (pipe_size/message_size) * message_size;
else
/* Insure that the size is in terms of UNSIGNED data elements. This
insures that the UNSIGNED word is never written past the end of
the pipe. */
pipe_size = (pipe_size/sizeof(UNSIGNED)) * sizeof(UNSIGNED);
pipe -> pi_available = pipe_size;
pipe -> pi_start = (BYTE_PTR) start_address;
pipe -> pi_end = pipe -> pi_start + pipe_size;
pipe -> pi_read = (BYTE_PTR) start_address;
pipe -> pi_write = (BYTE_PTR) start_address;
/* Clear the suspension list pointer. */
pipe -> pi_suspension_list = NU_NULL;
/* Clear the number of tasks waiting on the pipe counter. */
pipe -> pi_tasks_waiting = 0;
/* Clear the urgent message list pointer. */
pipe -> pi_urgent_list = NU_NULL;
/* Initialize link pointers. */
pipe -> pi_created.cs_previous = NU_NULL;
pipe -> pi_created.cs_next = NU_NULL;
/* Protect against access to the list of created pipes. */
TCT_Protect(&PID_List_Protect);
/* At this point the pipe is completely built. The ID can now be
set and it can be linked into the created pipe list. */
pipe -> pi_id = PI_PIPE_ID;
/* Link the pipe into the list of created pipes and increment the
total number of pipes in the system. */
CSC_Place_On_List(&PID_Created_Pipes_List, &(pipe -> pi_created));
PID_Total_Pipes++;
#ifdef NU_PROFILE_PLUS
PRF_PLUS_PIC_CREATE_PIPE_0
#endif /* NU_PROFILE_PLUS */
/* Release protection against access to the list of created pipes. */
TCT_Unprotect();
/* Return to user mode */
NU_USER_MODE();
/* Return successful completion. */
return(NU_SUCCESS);
}
/*************************************************************************/
/* */
/* FUNCTION */
/* */
/* PIC_Delete_Pipe */
/* */
/* DESCRIPTION */
/* */
/* This function deletes a pipe and removes it from the list of */
/* created pipes. All tasks suspended on the pipe are */
/* resumed. Note that this function does not free the memory */
/* associated with the pipe. */
/* */
/* CALLED BY */
/* */
/* Application */
/* PICE_Delete_Pipe Error checking shell */
/* */
/* CALLS */
/* */
/* CSC_Remove_From_List Remove node from list */
/* [HIC_Make_History_Entry] Make entry in history log */
/* TCC_Resume_Task Resume a suspended task */
/* [TCT_Check_Stack] Stack checking function */
/* TCT_Control_To_System Transfer control to system */
/* TCT_Protect Protect created list */
/* TCT_Set_Current_Protect Modify current protection */
/* TCT_System_Protect Protect against system access*/
/* TCT_System_Unprotect Release system protection */
/* TCT_Unprotect Release protection */
/* */
/* INPUTS */
/* */
/* pipe_ptr Pipe control block pointer */
/* */
/* OUTPUTS */
/* */
/* NU_SUCCESS */
/* */
/*************************************************************************/
STATUS PIC_Delete_Pipe(NU_PIPE *pipe_ptr)
{
R1 PI_PCB *pipe; /* Pipe control block ptr */
PI_SUSPEND *suspend_ptr; /* Suspend block pointer */
PI_SUSPEND *next_ptr; /* Next suspension block ptr */
STATUS preempt; /* Status for resume call */
NU_SUPERV_USER_VARIABLES
/* Switch to supervisor mode */
NU_SUPERVISOR_MODE();
/* Move input pipe pointer into internal pointer. */
pipe = (PI_PCB *) pipe_ptr;
#ifdef NU_ENABLE_STACK_CHECK
/* Call stack checking function to check for an overflow condition. */
TCT_Check_Stack();
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