#define NDEBUG
#include <algorithm>
#include <cassert>
// for some constant and type
#include "bbs.h"
/* for each login of user,
* input: my index, friend[MAX_FRIEND] of uid, reject[MAX_REJECT] of uid,
* for all my relation,
* output: his index, his uid, relation to me, relation to him
*/
/* 支 user utmp 銋憭, 券函 ref index 賣舫, 蝣箔 insert & delete O(1) */
/* 嗆鈭 refer resource recycle */
typedef int Uid;
typedef int Idx;
struct Relation {
Uid him;
short him_offset;
Relation(Uid _him, short _him_offset=-1) :him(_him),him_offset(_him_offset) {}
};
template<class T>
struct freelist {
static const int KEEP = 64;
static T* list[8][KEEP]; // 2^0~2^7
static int tail[8];
#define IS_2xxN(a) (a && (a&(a-1))==0)
static T* alloc(int n) {
assert(n>0);
if(n<256 && IS_2xxN(n) && sizeof(T)*n<65536) {
int t=n;
int slot;
for(slot=0; t>1; t/=2)
slot++;
assert(0<=slot && slot<8);
if(tail[slot]) {
return list[slot][--tail[slot]];
}
}
return (T*)malloc(sizeof(T)*n);
}
static void free(T* p, int n) {
assert(n>0);
if(n<256 && IS_2xxN(n) && sizeof(T)*n<65536) {
int t=n;
int slot;
for(slot=0; t>1; t/=2)
slot++;
assert(0<=slot && slot<8);
if(tail[slot]<KEEP) {
list[slot][tail[slot]++]=p;
return;
}
}
::free(p);
}
};
template<class T> T* freelist<T>::list[8][KEEP];
template<class T> int freelist<T>::tail[8]={0};
template<class T,int MIN_ROOM = 8, class S = int>
struct myvector {
// 憭扯港唾 STL vector, 雿 STL capacity 芣憓銝蝮桀
// (敺靘潛, 隞 online friend 靘隤, capacity 銝蝮桀嗅祕瘝隞暻澆蔣)
// 甇文, pointer 64bit 璈其閬 8bytes, basic overhead 8*3 bytes,
// 雿鞈瘝獐憭, 寧 S(int or short) 摮 size & capacity 瘥頛
T *base;
S room, n;
myvector() :base(0),room(0),n(0) {}
~myvector() {
clear();
}
S append(T data) {
if(room<n+1)
resizefor(n+1);
base[n++]=data;
return n-1;
}
void pop_back() {
assert(n>0);
n--;
resizefor(n);
}
void clear() {
n=0;
resizefor(n);
}
/*
T& operator[](int idx) {
return base[idx];
}
*/
void resizefor(S size) {
assert(size>=n);
if(size==0) {
if(base) freelist<T>::free(base, room);
base=0;
room=0;
} else {
S origroom=room;
if(room==0)
room=MIN_ROOM;
while(room<size) room=S(room*2);
if(size<MIN_ROOM) size=MIN_ROOM;
while(room/2>size) room=S(room/2);
if(room!=origroom || base==0) {
//base=(T*)realloc(base, sizeof(T)*room);
T* tmp=freelist<T>::alloc(room);
assert(tmp);
if(n>0)
memcpy(tmp, base, sizeof(T)*n);
if(base!=0)
freelist<T>::free(base, origroom);
base=tmp;
}
assert(base);
}
}
};
template<class R,class B>
struct RelationList: public myvector<Relation, 8, short> {
RelationList() :myvector<Relation, 8, short>() {}
void add(Uid me, Uid him) {
RelationList<B,R>& bl=R::backlist(him);
short me_offset=append(Relation(him));
short him_offset=bl.append(Relation(me,me_offset));
setbackoffset(me_offset,him_offset);
assert(bl.base[him_offset].him==me);
assert(bl.base[him_offset].him_offset==me_offset);
}
void deleteall(Uid me) {
for(int i=0; i<n; i++) {
RelationList<B,R>& bl=R::backlist(base[i].him);
assert(bl.base[base[i].him_offset].him==me);
assert(bl.base[base[i].him_offset].him_offset==i);
bl.delete_half(base[i].him_offset);
//try_recycle(base[i].him); // dirty
}
clear();
}
private:
void setbackoffset(short which,short offset) {
assert(0<=which && which<n);
base[which].him_offset=offset;
}
void delete_half(short offset) {
assert(0<=offset && offset<n);
if(offset<n-1) {
base[offset]=base[n-1];
R::backlist(base[offset].him).setbackoffset(base[offset].him_offset,offset);
}
pop_back();
}
friend class RelationList<B,R>;
};
struct Like;
struct Likeby;
struct Hate;
struct Hateby;
struct Like: public Relation {
Like(Uid _him, short _him_offset=-1) :Relation(_him,_him_offset) {}
static RelationList<Likeby,Like>& backlist(Uid him);
};
struct Likeby: public Relation {
Likeby(Uid _him, short _him_offset=-1) :Relation(_him,_him_offset) {}
static RelationList<Like,Likeby>& backlist(Uid him);
};
struct Hate: public Relation {
Hate(Uid _him, short _him_offset=-1) :Relation(_him,_him_offset) {}
static RelationList<Hateby,Hate>& backlist(Uid him);
};
struct Hateby: public Relation {
Hateby(Uid _him, short _him_offset=-1) :Relation(_him,_him_offset) {}
static RelationList<Hate,Hateby>& backlist(Uid him);
};
struct Utmp {
Utmp() {
for(int i=0; i<USHM_SIZE; i++)
utmp[i]=-1;
}
/*
Uid& operator[](int idx) {
return utmp[idx];
}
*/
public:
Uid utmp[USHM_SIZE];
};
static Utmp utmp;
struct BBSUser {
Uid me;
int online;
/* assume utmplist is short, so just use plain vector and linear search */
myvector<int,2> utmplist;
RelationList<Like,Likeby> like;
RelationList<Hate,Hateby> hate;
RelationList<Likeby,Like> likeby;
RelationList<Hateby,Hate> hateby;
BBSUser() :me(-1),online(0),utmplist(),like(),hate(),likeby(),hateby() {}
BBSUser(Uid uid) :me(uid),online(0),utmplist(),like(),hate(),likeby(),hateby() {}
void login(int utmpidx, const Uid likehim[MAX_FRIEND], const Uid hatehim[MAX_REJECT]) {
if(online>0) {
/* multiple login 閰, 隞交敺銝甈∠ like/hate 箸 */
like.deleteall(me);
hate.deleteall(me);
}
utmp.utmp[utmpidx]=me;
utmplist.append(utmpidx);
online++;
assert(online==utmplist.n);
for(int i=0; i<MAX_FRIEND && likehim[i]; i++)
like.add(me, likehim[i]);
for(int i=0; i<MAX_REJECT && hatehim[i]; i++)
hate.add(me, hatehim[i]);
}
void logout(int utmpidx) {
assert(utmp.utmp[utmpidx]==me);
assert(online==utmplist.n);
for(int i=0; i<utmplist.n; i++)
if(utmplist.base[i]==utmpidx) {
utmplist.base[i]=utmplist.base[utmplist.n-1];
utmplist.pop_back();
break;
}
utmp.utmp[utmpidx]=-1;
online--;
assert(online==utmplist.n);
if(online==0) {
like.deleteall(me);
hate.deleteall(me);
}
}
bool isfree() const {
return online==0 && like.n==0 && hate.n==0 && likeby.n==0 && hateby.n==0;
}
};
struct UserList {
BBSUser users[MAX_USERS];
UserList() {
for(int i=0; i<MAX_USERS; i++)
users[i].me=i;
}
void login(Uid uid, Idx idx, const Uid likehim[MAX_FRIEND], const Uid hatehim[MAX_REJECT]) {
assert(uid<MAX_USERS);
assert(idx<USHM_SIZE);
/* 望潔嗅 logout event, 甇 logout 芰潛 utmp override */
if(utmp.utmp[idx]!=-1) users[utmp.utmp[idx]].logout(idx);
users[uid].login(idx, likehim, hatehim);
}
};
struct UserList userlist;
RelationList<Likeby,Like>& Like::backlist(Uid him) { return userlist.users[him].likeby; }
RelationList<Like,Likeby>& Likeby::backlist(Uid him) { return userlist.users[him].like; }
RelationList<Hateby,Hate>& Hate::backlist(Uid him) { return userlist.users[him].hateby; }
RelationList<Hate,Hateby>& Hateby::backlist(Uid him) { return userlist.users[him].hate; }
struct Result {
Uid who;
int bits;
Result(Uid _who, int _bits) :who(_who),bits(_bits) {}
bool operator<(const Result& b) const {
return who<b.who;
}
};
int reverse_friend_stat(int stat)
{
int stat1 = 0;
if (stat & IFH) stat1 |= HFM;
if (stat & IRH) stat1 |= HRM;
if (stat & HFM) stat1 |= IFH;
if (stat & HRM) stat1 |= IRH;
return stat1;
}
extern "C" void utmplogin(int uid, int index, const int like[MAX_FRIEND], const int hate[MAX_REJECT])
{
/* login */
userlist.login(uid, index, like, hate);
}
extern "C" int genfriendlist(int uid, int index, ocfs_t *fs, int maxfs)
{
/* collect data */
BBSUser& u=userlist.users[uid];
myvector<Result,64,short> work;
for(int i=0; i<u.like.n; i++) work.append(Result(u.like.base[i].him, IFH));
for(int i=0; i<u.hate.n; i++) work.append(Result(u.hate.base[i].him, IRH));
for(int i=0; i<u.likeby.n; i++) work.append(Result(u.likeby.base[i].him, HFM));
for(int i=0; i<u.hateby.n; i++) work.append(Result(u.hateby.base[i].him, HRM));
/* sort */
std::sort(work.base, work.base+work.n);
/* merge */
if(work.n>0) {
int newn=1;
for(int i=1; i<work.n; i++)
if(work.base[i].who==work.base[newn-1].who) {
work.base[newn-1].bits|=work.base[i].bits;
} else {
work.base[newn++]=work.base[i];
}
work.n=newn;
}
/* fill */
int nfs=0;
for(int i=0; i<work.n && nfs<maxfs; i++) {
BBSUser& h=userlist.users[work.base[i].who];
for(int j=0; j<h.utmplist.n && nfs<maxfs; j++) {
int rstat=reverse_friend_stat(work.base[i].bits);
if(h.utmplist.base[j]==index) continue;
fs[nfs].index=h.utmplist.base[j];
fs[nfs].uid=h.me;
fs[nfs].friendstat=(work.base[i].bits<<24)|h.utmplist.base[j];
fs[nfs].rfriendstat=(rstat<<24)|index;
nfs++;
}
}
return nfs;
}
extern "C" void utmplogoutall(void)
{
for(int i=0; i<USHM_SIZE; i++)
if(utmp.utmp[i]!=-1)
userlist.users[utmp.utmp[i]].logout(i);
}
