// 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::create(const string & fileName)
{
int file;
if ((file = ::open(fileName.c_str(), O_CREAT | O_EXCL | O_WRONLY, 0666)) < 0)
{
if (errno == EEXIST)
return FILEEXISTS;
else
return UNIXERR;
}
// An empty file contains just a DB header page.
Page header;
memset(&header, 0, sizeof header);
DBP(header).nextFree = -1;
DBP(header).firstPage = -1;
DBP(header).numPages = 1;
if (write(file, (char*)&header, sizeof header) != sizeof header)
return UNIXERR;
if (::close(file) < 0)
return UNIXERR;
return OK;
}
parser_state *
PyParser_New(grammar *g, int start)
{
parser_state *ps;
DBP("Attempting to create new PyParser\n");
if (!g->g_accel)
PyGrammar_AddAccelerators(g);
DBP("Added grammar accelerators\n");
ps = (parser_state *)PyMem_MALLOC(sizeof(parser_state));
DBP("Created parser state\n");
if (ps == NULL)
return NULL;
ps->p_grammar = g;
#ifdef PY_PARSER_REQUIRES_FUTURE_KEYWORD
ps->p_flags = 0;
#endif
ps->p_tree = PyNode_New(start);
if (ps->p_tree == NULL) {
PyMem_FREE(ps);
return NULL;
}
s_reset(&ps->p_stack);
(void) s_push(&ps->p_stack, PyGrammar_FindDFA(g, start), ps->p_tree);
DBP("Created PyParser!!\n");
return ps;
}
void testLazyFailureFunctionRandom(std::string const & pattern)
{
::libmaus::autoarray::AutoArray<int64_t> BP = ::libmaus::util::KMP::BEST_PREFIX(pattern.begin(),pattern.size());
::libmaus::random::Random::setup();
for ( uint64_t i = 0; i < 16*1024*1024; ++i )
{
std::istringstream pistr(pattern);
::libmaus::util::KMP::BestPrefix<std::istream> DBP(pistr,pattern.size());
std::vector<uint64_t> probes;
for ( uint64_t j = 0; j < 2*pattern.size(); ++j )
probes.push_back( ::libmaus::random::Random::rand64() % (BP.size()) );
#if 0
for ( uint64_t i = 0; i < probes.size(); ++i )
std::cerr << BP[probes[i]] << ";";
std::cerr << std::endl;
#endif
for ( uint64_t i = 0; i <= pattern.size(); ++i )
{
assert ( DBP[probes[i]] == BP[probes[i]] );
#if 0
std::cerr << DBP[probes[i]] << ";";
#endif
}
#if 0
std::cerr << std::endl;
#endif
}
}
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;
}
void DBPt(const char *fmt, ...)
{
char *Str;
va_list vlist;
Str = malloc(1024);
va_start(vlist, fmt);
vsprintf(Str, fmt, vlist);
va_end(vlist);
DBP("%s", Str);
}
// 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;
}
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;
}
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;
}
