//******************************************************************************
//MI02                  MANAGEMENT INFORMATION                                 *
//    DEVICE  ID:  2f129                 HID:       N/A                        *
//    FILENAME:    sparemem.c            LANGUAGE:  C                          *
//    LOAD MODUL:  sparemem              SYSTEM:    Utility                    *
//    COMPILER:    cc                    UNIT:      sparemem                   *
//    ITRNR RATE:  N/A                   CPU TYPE:  Intel Pentium              *
//    LINK EDITOR: ld                    MODE:      N/A                        *
//                                                                             *
//******************************************************************************
//PU01                PURPOSE - AMENDED                                        *
//                                                                             *
//    Spare memory test program.                                               *
//                                                                             *
//******************************************************************************
//PU02                  PURPOSE                                                *
//    Spare memory test program.                                               *
//                                                                             *
//                                                                             *
//  The software requirements being implemented by this task are identified    *
//  by STLDD paragraph number 3.6.?                                            *
//                                                                             *
//******************************************************************************
//PA02                  PROGRAM ATTRIBUTES                                     *
//    LOGICAL RECORDS:                   GENERAL COMMENTS:                     *
//    C LINES:                           NON-C LINES:                          *
//    EXECUTABLE C STMTS:                NON-EXEC C STMTS:                     *
//                                                                             *
//******************************************************************************
//SU01                  SUBPROGRAM USAGE                                       *
//                                                                             *
//******************************************************************************
//CH02                  CHANGE HISTORY                                         *
//    REV    DATE    ANALYST        EMPLOYER       DESCRIPTION                 *
//    0      010199  Jon Clifton    ASI            Initial release             *
//                                                                             *
//******************************************************************************
//ML01                  MODULE LOGIC                                           *
//                                                                             *
//******************************************************************************
//ME01                  MODULE EXECUTION CONDITIONS                            *
//                                                                             *
//   Standalone test of available spare memory. Requests all memory not        *
//   used by OS and REALTIME tasks.                                            *
//                                                                             *
//******************************************************************************
//CI01                  LIBRARY AND USER HEADER FILES                          *
//                                                                             *

#include <sys/time.h>
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/fcntl.h>
#include <unistd.h>
#include <sched.h>
#include <errno.h>
#include <sys/mman.h>
//******************************************************************************
//CC01                  GLOBAL CONSTANTS                                       *
//                                                                             *
#define verbose 1
#define PRIORITY 90
#define ONE_MB 0x100000
//******************************************************************************
//CE01                  EXTERNALLY DEFINED VARIABLES                           *
//                                                                             *
//******************************************************************************
//CT01                  STRUCTURE DEFINITIONS                                  *
//                                                                             *
//******************************************************************************
//CG01                  GLOBAL SYMBOL DECLARATIONS                             *
//                                                                             *
//******************************************************************************
//CS01                  STATIC SYMBOL DECLARATIONS                             *
//                                                                             *
//******************************************************************************
//CP01                  MODULE PROTOTYPES                                      *
//                                                                             *
//******************************************************************************
//SC01                  SOURCE CODE                                            *
//                                                                             *
void main()
{
//******************************************************************************
//LC01                  LOCAL SYMBOL DECLARATIONS                              *
//                                                                             *
  int i,j, k;                               // loop counters
  char* sparemem_p;                         // pointer to memory allocated
  int*  dirty_p;                            // pointer to dirty up memory
  int mb_mem=ONE_MB;                        // size of memory allocated
  int pid;                                  // Process ID
  struct sched_param sched;
//******************************************************************************
//EX01                  EXECUTABLE STATEMENTS                                  *
//                                                                             *
//******************************************************************************
 
  pid = (int) getpid();
  if (0 != geteuid()) {
    printf("ex1exec: MUST BE ROOT TO LOCK MEMORY\n");
    exit(1);
  }

  /**************************************************************
   * Change scheduling to FIFO for Real_Time.                   *
   * Must be root or setuid root to execute sched_setscheduler. *
   **************************************************************/
//sched.sched_priority = PRIORITY;
//i = sched_setscheduler(0, SCHED_FIFO, &sched);
  if (i) perror("sched_setscheduler failed");  
  i = sched_getscheduler(0);
  if (i<0) perror("sched_getscheduler failed");  
  else printf("Schedule policy %d, ", i);
  i = sched_getparam(0, &sched);
  if (i<0) perror("sched_getparam failed");  
  else printf("priority %d\n",
               sched.sched_priority);

  /*********************************************************
   * Must be root or setuid root to execute mlockall       *
   *********************************************************/

  while (NULL != (sparemem_p=(char*)malloc(ONE_MB))) {
    printf("Trying to allocate %d MB\n",mb_mem/ONE_MB);
    i = mlockall(MCL_CURRENT);
    if (i) {
      perror("mlockall failed");  
      break;
    }
//  memset(sparemem_p,mb_mem, '!');
    srand(pid);
    dirty_p = (int*)sparemem_p;
    for (i=0;i<(ONE_MB/sizeof(int));i++) {
      *dirty_p++ = rand();
    }
//   i = munlockall();
//  if (i) {
//    perror("munlockall failed");  
//    break;
//  }
//  free(sparemem_p);
    mb_mem+=ONE_MB;
  };
  printf("Available memory = %d MB\n",mb_mem/ONE_MB);
  for (;;) rand();
  return;
} /* end of sparemem */