INT wmain(INT argc, WCHAR **argv)
{
po::variables_map vm;
printInfoStruct printInfo = { };
INT r = parseArguments(argc, argv, vm, printInfo);
if (r != -1)
return r;
if(!printInfo.user.empty())
return printOutput(countProcs(printInfo.user), printInfo);
return printOutput(countProcs(), printInfo);
}
/* pre: takes in int argc and char** argv command line agruments
* post: runs the virtual memory simulation program
* return: 0 on success, else 1
*/
int main(int argc, char** argv)
{
/* parameters */
char* plist; /* path to plist file */
char* ptrace; /* path to ptrace file */
int pageSize; /* page size */
char* pageReplacement; /* page replacement method */
int prePaging; /* "boolean" for pre-paging vs demand */
/* other variables */
FILE* plistfd; /* file handle for plist file */
FILE* ptracefd; /* file handle for ptrace file */
int numProcs; /* number of processes in plist */
ptable** proc_ptables; /* list of page tables (one for each process in plist) */
int perProcMem; /* amount of memory locations in main memory per process */
unsigned long cycle; /* "clock" cycle for LRU */
/* temporary variables and return codes */
int i;
int j;
char* line;
size_t len;
ssize_t ret;
ptable* temp_ptable;
/* verifiy number of arguments */
if (argc != 6)
{
printf("usage: %s <plist> <ptrace> <page size> <FIFO|LRU|Clock> <+|- pre-paging on/off>\n",
argv[0]);
return 1;
}
else /* parse and error check arguments */
{
plist = argv[1];
ptrace = argv[2];
pageSize = atoi(argv[3]);
if (pageSize <= 0 || !isPowTwo(pageSize) || pageSize > MAX_PAGE_SIZE)
{
printf("[ERROR]\tInvalid page size [%s]!\n", argv[3]);
printf(" \tPlease use a positive power of 2 up to 32\n");
return 1;
}
pageReplacement = argv[4];
if (strcmp(pageReplacement, OPT_FIFO) &&
strcmp(pageReplacement, OPT_LRU) &&
strcmp(pageReplacement, OPT_CLOCK))
{
printf("[ERROR]\tInvalid page replacement method!\n");
printf(" \tPlease use one of: [%s], [%s] or [%s]\n",
OPT_FIFO, OPT_LRU, OPT_CLOCK);
return 1;
}
if (!strcmp(argv[5], "+"))
prePaging = 1;
else if (!strcmp(argv[5], "-"))
prePaging = 0;
else
{
printf("[ERROR]\tInvalid value for pre-paging!\n");
printf(" \tPlease use either [+] for on or [-] for off\n");
return 1;
}
#ifdef DEBUG
printf("[DEBUG]\tplist: %s\n[DEBUG]\tptrace: %s\n[DEBUG]\tpageSize: %d\n\
[DEBUG]\tpageReplacement: %s\n[DEBUG]\tprePaging: %d\n",
plist, ptrace, pageSize, pageReplacement, prePaging);
fflush(stdout);
#endif
}
/* initialize page swap counter to zero for start */
gl_page_swaps = 0;
/* open files for reading */
plistfd = fopen(plist, "r");
if (plistfd == NULL)
{
printf("[ERROR]\tCould not open plist file!\n");
return 1;
}
ptracefd = fopen(ptrace, "r");
if (ptracefd == NULL)
{
printf("[ERROR]\tCould not open ptrace file!\n");
return 1;
}
/* read from plist to count the number of lines (processes) */
numProcs = countProcs(plistfd);
#ifdef DEBUG
printf("[DEBUG]\t%d processes detected\n", numProcs);
fflush(stdout);
#endif
/* skip over everything if we have zero or less processes */
if (numProcs > 0)
{
/* create a list of page tables (one for each process) */
proc_ptables = (ptable**)malloc(sizeof(ptable*)*numProcs);
if (proc_ptables == NULL)
{
printf("[ERROR]\t could not allocate memory for page tables!\n");
return 1;
}
/* move the fd back to the start of the file so we can read it again */
rewind(plistfd);
/* read from plist again to setup proc_ptables */
i = 0;
line = NULL;
len = 0;
while ((ret = getline(&line, &len, plistfd)) != -1)
{
/* skip over all empty lines */
if (!strcmp(line, "\n"))
continue;
#if defined (DEBUG) && !defined (NO_SPAM)
printf("[DEBUG]\tRead plist line: %s", line);
fflush(stdout);
#endif
/* this returns the PID, next strtok will be the mem locs */
strtok(line, " ");
proc_ptables[i] = createPageTable(pageSize, atoi(strtok(NULL, " ")));
if (proc_ptables[i] == NULL)
{
printf("[ERROR]\tCould not allocate memory for page table!\n");
return 1;
}
i++;
}
/* load initial main memory */
perProcMem = (int)floor((double)MAX_MEM / (numProcs * pageSize));
#ifdef DEBUG
printf("[DEBUG]\tEach process gets %d main mem entries\n", perProcMem);
fflush(stdout);
#endif
/* for each program set the first perProcMem pages as valid (in main mem ) */
for (i = 0; i < numProcs; i++)
{
for (j = 0; j < perProcMem && j < proc_ptables[i]->numPages; j++)
{
validatePage(proc_ptables[i], j);
#if defined (DEBUG) && !defined (NO_SPAM)
printf("[DEBUG]\tInitial load: [%d] [%d] = [%d]\n",
i, j, proc_ptables[i]->pages[j]->valid);
fflush(stdout);
#endif
/* if we're using FIFO or Clock page replacement */
if (!strcmp(pageReplacement, OPT_FIFO))
pushFifo(proc_ptables[i], j);
else if (!strcmp(pageReplacement, OPT_CLOCK))
pushClock(proc_ptables[i], j);
}
#ifdef DEBUG
printf("[DEBUG]\tProcess [%d] loaded [%d] pages\n",
i,
proc_ptables[i]->numLoaded);
fflush(stdout);
#endif
}
/* read from ptrace and run the simulation */
free(line);
line = NULL;
len = 0;
cycle = 1;
while ((ret = getline(&line, &len, ptracefd)) != -1)
{
/* skip over all empty lines */
if (!strcmp(line, "\n"))
continue;
#if defined (DEBUG) && !defined (NO_SPAM)
printf("[DEBUG]\tRead ptrace line: %s", line);
fflush(stdout);
#endif
/* this returns the PID, next strtok will be the mem loc to access */
i = atoi(strtok(line, " "));
/* set temporary page table to this program's page table */
temp_ptable = proc_ptables[i];
/* get mem loc to access */
j = atoi(strtok(NULL, " "));
j = (int)ceil((double)j/pageSize);
j--; /* translate to zero index */
/* 'i' is now the process number and 'j' is now the page number to access */
#if defined (DEBUG) && !defined (NO_SPAM)
printf("[DEBUG]\tAbout to access process [%d] page [%d] of [%d] total pages\n",
i,
j,
temp_ptable->numPages);
fflush(stdout);
#endif
/* try to access temp_ptable->pages[j] */
if (temp_ptable->pages[j]->valid) /* page hit (in main memory) */
{
if (!strcmp(pageReplacement, OPT_LRU))
temp_ptable->pages[j]->accessed = cycle;
else if (!strcmp(pageReplacement, OPT_CLOCK))
accessClock(temp_ptable, j);
}
else /* page miss (need to swap) */
{
/* record this page fault */
gl_page_swaps++;
if (prePaging)
prePagingSwap(pageReplacement, temp_ptable, j, perProcMem, cycle);
else /* demand paging */
demandSwap(pageReplacement, temp_ptable, j, perProcMem, cycle);
}
/* check to make sure process is within memory limits */
if (temp_ptable->numLoaded > perProcMem)
{
printf("[ERROR]\tProcess has exceeded memory!\n");
return 1;
}
/* update cycle counter for LRU */
cycle++;
}
free(line);
}
/* close files, ignoring any errors on close */
fclose(plistfd);
fclose(ptracefd);
/* free memory */
if (proc_ptables)
{
for (i = 0; i < numProcs; i++)
deletePageTable(proc_ptables[i]);
free(proc_ptables);
}
/* print total number of page swaps on exit */
printf("Total page swaps: %lu\n", gl_page_swaps);
return 0;
}
