// Check if the page is on the free list. Requires traversing the link list
// More efficient data structures are possible!
const Status File::onFreeList(const int pageNo, bool& onFL) const
{
int pgNo;
Page header;
Status status;
onFL = false;
if ((status = intread(0, &header)) != OK)
return status;
// Check the free list pages
if (DBP(header).nextFree != -1) // Free list exists
{
while ((pgNo = DBP(header).nextFree) != -1)
{
if (pageNo == pgNo)
{
onFL = true;
return OK;
}
// Read the next page;
if ((status = intread(pgNo, &header)) != OK)
return status;
}
}
return OK;
}
const Status File::allocatePage(int& pageNo)
{
Page header;
Status status;
if ((status = intread(0, &header)) != OK)
return status;
// If free list has pages on it, take one from there
// and adjust free list accordingly.
if (DBP(header).nextFree != -1) { // free list exists?
// Return first page on free list to the caller,
// adjust free list accordingly.
pageNo = DBP(header).nextFree;
Page firstFree;
if ((status = intread(pageNo, &firstFree)) != OK)
return status;
DBP(header).nextFree = DBP(firstFree).nextFree;
} else { // no free list, have to extend file
// Extend file -- the current number of pages will be
// the page number of the page to be returned.
pageNo = DBP(header).numPages;
Page newPage;
memset(&newPage, 0, sizeof newPage);
if ((status = intwrite(pageNo, &newPage)) != OK)
return status;
DBP(header).numPages++;
if (DBP(header).firstPage == -1) // first user page in file?
DBP(header).firstPage = pageNo;
}
if ((status = intwrite(0, &header)) != OK)
return status;
#ifdef DEBUGFREE
listFree();
#endif
return OK;
}
/*
* "Window" change handler
*/
winch()
{
(void)signal(SIGWIND, winch);
sigs |= S_WINCH;
if (reading)
intread();
}
/*
* "Stop" (^Z) signal handler.
*/
static void
stop()
{
(void)signal(SIGTSTP, stop);
sigs |= S_STOP;
if (reading)
intread();
}
const Status File::readPage(const int pageNo, Page* pagePtr) const
{
if (!pagePtr)
return BADPAGEPTR;
if (pageNo < 1)
return BADPAGENO;
return intread(pageNo, pagePtr);
}
const Status File::getFirstPage(int& pageNo) const
{
Page header;
Status status;
if ((status = intread(0, &header)) != OK)
return status;
pageNo = DBP(header).firstPage;
return OK;
}
// Deallocate a page from file. The page will be put on a free
// list and returned back to the caller upon a subsequent
// allocPage() call.
// ALERT: No error returned if disposePage called on the same page twice!
const Status File::disposePage(int pageNo)
{
if (pageNo < 1)
return BADPAGENO;
Page header;
Status status;
if ((status = intread(0, &header)) != OK)
return status;
// The first user-allocated page in the file cannot be
// disposed of. The File layer has no knowledge of what
// is the next page in the file and hence would not be
// able to adjust the firstPage field in file header.
if (DBP(header).firstPage == pageNo || pageNo >= DBP(header).numPages)
return BADPAGENO;
// Deallocate page by attaching it to the free list.
Page away;
if ((status = intread(pageNo, &away)) != OK)
return status;
memset(&away, 0, sizeof away);
DBP(away).nextFree = DBP(header).nextFree;
DBP(header).nextFree = pageNo;
if ((status = intwrite(pageNo, &away)) != OK)
return status;
if ((status = intwrite(0, &header)) != OK)
return status;
#ifdef DEBUGFREE
listFree();
#endif
return OK;
}
void File::listFree()
{
cerr << "%% File " << (int)this << " free pages:";
int pageNo = 0;
for(int i = 0; i < 10; i++) {
Page page;
if (intread(pageNo, &page) != OK)
break;
pageNo = DBP(page).nextFree;
cerr << " " << pageNo;
if (pageNo == -1)
break;
}
cerr << endl;
}
const Status File::readPage(int pageNo, Page* pagePtr) const
{
if (!pagePtr)
return BADPAGEPTR;
if (pageNo < 1)
return BADPAGENO;
bool onFL;
Status status;
if ((status = onFreeList(pageNo, onFL)) != OK)
return status;
if (onFL)
return BADPAGENO; // The page is on the free list.
else
return intread(pageNo, pagePtr);
}
int readmap ()
{
int x;
file = fopen(temp,"r");
if(file == FALSE)
return 1;
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
scripts = intread(ts);
fread(&enemytf,1,1,file);
if(enemytf == 'y')
enemytf = TRUE;
fread(&npctf,1,1,file);
if(npctf == 'y')
npctf = TRUE;
if (npctf == TRUE)
{
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
npcnum = intread(ts);
}
fread(&startmaptf,1,1,file);
if(startmaptf == 'y')
startmaptf = TRUE;
if (startmaptf == TRUE)
{
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
startx = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
starty = intread(ts);
}
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
warpnum = intread(ts);
for (maprunx = 0; maprunx < 20; maprunx++)
{
fread(&mapname [maprunx],1,1,file);
}
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mapx = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mapy = intread(ts);
for (mapruny = 0; mapruny < mapy; mapruny++)
{
for (maprunx = 0; maprunx < mapx; maprunx++)
{
fread(&map [maprunx][mapruny],1,1,file);
}
}
for (mapruny = 0; mapruny < mapy; mapruny++)
{
for (maprunx = 0; maprunx < mapx; maprunx++)
{
fread(&maperm [maprunx][mapruny],1,1,file);
}
}
for (mapruny = 0; mapruny < warpnum; mapruny++)
{
for (maprunx = 0; maprunx < 12; maprunx++)
{
fread(&mapwarps [mapruny].mapname [maprunx],1,1,file);
}
mapwarps[mapruny].mapname[12] = '\0';
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mapwarps [mapruny].x [0] = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mapwarps [mapruny].y [0] = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mapwarps [mapruny].x [1] = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mapwarps [mapruny].y [1] = intread(ts);
}
for (mapruny = 0; mapruny < scripts; mapruny++)
{
for (maprunx = 0; maprunx < 12; maprunx++)
{
fread(&mscript [mapruny].scriptfilename [maprunx],1,1,file);
}
mscript [mapruny].scriptfilename [12] = '\0';
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mscript [mapruny].fdependsnum = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mscript [mapruny].fnotifnum = intread(ts);
for (maprunx = 0; maprunx < mscript [mapruny].fdependsnum; maprunx++)
{
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mscript [mapruny].fdepends[maprunx] = intread(ts);
}
for (maprunx = 0; maprunx < mscript [mapruny].fnotifnum; maprunx++)
{
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
mscript [mapruny].fnotif[maprunx] = intread(ts);
}
}
fread(&enemytf,1,1,file);
if(enemytf == 'y')
enemytf = TRUE;
if (enemytf == TRUE)
{
for (mapruny = 0; mapruny < 10; mapruny++)
{
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
enemyent [0][mapruny] = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
enemyent [1][mapruny] = intread(ts);
}
}
if (npctf == TRUE)
{
for (maprunz = 0;maprunz < npcnum; maprunz++)
{
fread(&people [maprunz].name [0],1,1,file);
fread(&people [maprunz].name [1],1,1,file);
fread(&people [maprunz].name [2],1,1,file);
fread(&people [maprunz].name [3],1,1,file);
fread(&people [maprunz].name [4],1,1,file);
fread(&people [maprunz].name [5],1,1,file);
fread(&people [maprunz].name [6],1,1,file);
fread(&people [maprunz].name [7],1,1,file);
fread(&people [maprunz].name [8],1,1,file);
fread(&people [maprunz].name [9],1,1,file);
fread(&people [maprunz].name [10],1,1,file);
fread(&people [maprunz].name [11],1,1,file);
for (maprunx = 0; maprunx < 13; maprunx++)
{
fread(&people [maprunz].scriptfile [maprunx],1,1,file);
}
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
people [maprunz].x = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
people [maprunz].y = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
people [maprunz].movetype = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
people [maprunz].fdependsnum = intread(ts);
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
people [maprunz].fnotifnum = intread(ts);
for (maprunx = 0; maprunx < people [maprunz].fdependsnum; maprunx++)
{
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
people [maprunz].fdepends[maprunx] = intread(ts);
}
for (maprunx = 0; maprunx < people [maprunz].fnotifnum; maprunx++)
{
for(x = 0; x < 10; x++)
{
fread(&ts[x],1,1,file);
}
people [maprunz].fnotif[maprunx] = intread(ts);
}
}
}
fclose(file);
return 0;
}
