📄 smc.c
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/*************************************************************************//* *//* Copyright Mentor Graphics Corporation 2002 *//* 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 *//* *//* smc.c Nucleus PLUS 1.14 *//* *//* COMPONENT *//* *//* SM - Semaphore Management *//* *//* DESCRIPTION *//* *//* This file contains the core routines for the Semaphore Management*//* component. *//* *//* DATA STRUCTURES *//* *//* None *//* *//* FUNCTIONS *//* *//* SMC_Create_Semaphore Create a semaphore *//* SMC_Delete_Semaphore Delete a semaphore *//* SMC_Obtain_Semaphore Obtain instance of semaphore *//* SMC_Release_Semaphore Release instance of semaphore*//* SMC_Cleanup Cleanup on timeout or a *//* terminate condition *//* *//* DEPENDENCIES *//* *//* cs_extr.h Common Service functions *//* tc_extr.h Thread Control functions *//* sm_extr.h Semaphore functions *//* hi_extr.h History functions *//* *//* HISTORY *//* *//* DATE REMARKS *//* *//* 03-01-1993 Created initial version 1.0 *//* 04-19-1993 Verified version 1.0 *//* 08-09-1993 Corrected pointer retrieval *//* loop, resulting in version 1.0a *//* 08-09-1993 Verified version 1.0a *//* 03-01-1994 Moved non-core functions into *//* supplemental files, changed *//* function interfaces to match *//* those in prototype, added *//* register options, changed *//* protection logic to reduce *//* overhead, resulting in *//* version 1.1 *//* *//* 03-18-1994 Verified version 1.1 *//* 04-17-1996 updated to version 1.2 *//* 03-24-1998 Released version 1.3 *//* 03-26-1999 Released 1.11m (new release *//* numbering scheme) *//* 04-17-2002 Released version 1.13m *//* 11-07-2002 Released version 1.14 *//*************************************************************************/#define NU_SOURCE_FILE#include "cs_extr.h" /* Common service functions */#include "tc_extr.h" /* Thread control functions */#include "sm_extr.h" /* Semaphore functions */#include "hi_extr.h" /* History functions */#include "profiler.h" /* ProView interface *//* Define external inner-component global data references. */extern CS_NODE *SMD_Created_Semaphores_List;extern UNSIGNED SMD_Total_Semaphores;extern TC_PROTECT SMD_List_Protect;/* Define internal component function prototypes. */VOID SMC_Cleanup(VOID *information);/*************************************************************************//* *//* FUNCTION *//* *//* SMC_Create_Semaphore *//* *//* DESCRIPTION *//* *//* This function creates a semaphore and then places it on the list *//* of created semaphores. *//* *//* CALLED BY *//* *//* Application *//* SMCE_Create_Semaphore Error checking shell *//* *//* CALLS *//* *//* CSC_Place_On_List Add 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 *//* *//* semaphore_ptr Semaphore control block ptr *//* name Semaphore name *//* initial_count Initial semaphore instance *//* count *//* suspend_type Suspension type *//* *//* OUTPUTS *//* *//* NU_SUCCESS *//* *//* HISTORY *//* *//* DATE REMARKS *//* *//* 03-01-1993 Created initial version 1.0 *//* 04-19-1993 Verified version 1.0 *//* 03-01-1994 Changed function interfaces to *//* match those in prototype, *//* added register options, *//* resulting in version 1.1 *//* *//* 03-18-1994 Verified version 1.1 *//* *//*************************************************************************/STATUS SMC_Create_Semaphore(NU_SEMAPHORE *semaphore_ptr, CHAR *name, UNSIGNED initial_count, OPTION suspend_type){R1 SM_SCB *semaphore; /* Semaphore control blk ptr */INT i; /* Working index variable */NU_SUPERV_USER_VARIABLES /* Switch to supervisor mode */ NU_SUPERVISOR_MODE(); /* Move input semaphore pointer into internal pointer. */ semaphore = (SM_SCB *) semaphore_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_SEMAPHORE_ID, (UNSIGNED) semaphore, (UNSIGNED) name, (UNSIGNED) initial_count);#endif /* First, clear the semaphore ID just in case it is an old Semaphore Control Block. */ semaphore -> sm_id = 0; /* Fill in the semaphore name. */ for (i = 0; i < NU_MAX_NAME; i++) semaphore -> sm_name[i] = name[i]; /* Setup the initial semaphore instance count. */ semaphore -> sm_semaphore_count = initial_count; /* Setup the semaphore suspension type. */ if (suspend_type == NU_FIFO) /* FIFO suspension is selected, setup the flag accordingly. */ semaphore -> sm_fifo_suspend = NU_TRUE; else /* Priority suspension is selected. */ semaphore -> sm_fifo_suspend = NU_FALSE; /* Clear the suspension list pointer. */ semaphore -> sm_suspension_list = NU_NULL; /* Clear the number of tasks waiting on the semaphore counter. */ semaphore -> sm_tasks_waiting = 0; /* Initialize link pointers. */ semaphore -> sm_created.cs_previous = NU_NULL; semaphore -> sm_created.cs_next = NU_NULL; /* Protect against access to the list of created semaphores. */ TCT_Protect(&SMD_List_Protect); /* At this point the semaphore is completely built. The ID can now be set and it can be linked into the created semaphore list. */ semaphore -> sm_id = SM_SEMAPHORE_ID; /* Link the semaphore into the list of created semaphores and increment the total number of semaphores in the system. */ CSC_Place_On_List(&SMD_Created_Semaphores_List,&(semaphore -> sm_created)); SMD_Total_Semaphores++;#ifdef INCLUDE_PROVIEW _RTProf_DumpSema(RT_PROF_CREATE_SEMAPHORE,semaphore, RT_PROF_OK);#endif /* Release protection against access to the list of created semaphores. */ TCT_Unprotect(); /* Return to user mode */ NU_USER_MODE(); /* Return successful completion. */ return(NU_SUCCESS);}/*************************************************************************//* *//* FUNCTION *//* *//* SMC_Delete_Semaphore *//* *//* DESCRIPTION *//* *//* This function deletes a semaphore and removes it from the list *//* of created semaphores. All tasks suspended on the semaphore are *//* resumed. Note that this function does not free the memory *//* associated with the semaphore control block. *//* *//* CALLED BY *//* *//* Application *//* SMCE_Delete_Semaphore 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 Setup system protection *//* TCT_System_Unprotect Release system protection *//* TCT_Unprotect Release protection *//* *//* INPUTS *//* *//* semaphore_ptr Semaphore control block ptr *//* *//* OUTPUTS *//* *//* NU_SUCCESS */
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