server/include/util.h

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 * 
 * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 * 
 * Deliantra is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 * 
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

#ifndef UTIL_H__
#define UTIL_H__

#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
#define DEBUG_SALLOC  0   // add a debug wrapper around all sallocs
#define PREFER_MALLOC 0   // use malloc and not the slice allocator

#if __GNUC__ >= 3
# define is_constant(c)             __builtin_constant_p (c)
# define expect(expr,value)         __builtin_expect ((expr),(value))
# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
#else
# define is_constant(c)             0
# define expect(expr,value)         (expr)
# define prefetch(addr,rw,locality)
#endif

#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
# define decltype(x) typeof(x)
#endif

// put into ifs if you are very sure that the expression
// is mostly true or mosty false. note that these return
// booleans, not the expression.
#define expect_false(expr) expect ((expr) != 0, 0)
#define expect_true(expr)  expect ((expr) != 0, 1)

#include <pthread.h>

#include <cstddef>
#include <cmath>
#include <new>
#include <vector>

#include <glib.h>

#include <shstr.h>
#include <traits.h>

#if DEBUG_SALLOC
# define g_slice_alloc0(s) debug_slice_alloc0(s)
# define g_slice_alloc(s) debug_slice_alloc(s)
# define g_slice_free1(s,p) debug_slice_free1(s,p)
void *g_slice_alloc (unsigned long size);
void *g_slice_alloc0 (unsigned long size);
void g_slice_free1 (unsigned long size, void *ptr);
#elif PREFER_MALLOC
# define g_slice_alloc0(s) calloc (1, (s))
# define g_slice_alloc(s) malloc ((s))
# define g_slice_free1(s,p) free ((p))
#endif

// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
#define auto(var,expr) decltype(expr) var = (expr)

// very ugly macro that basicaly declares and initialises a variable
// that is in scope for the next statement only
// works only for stuff that can be assigned 0 and converts to false
// (note: works great for pointers)
// most ugly macro I ever wrote
#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)

// in range including end
#define IN_RANGE_INC(val,beg,end) \
  ((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))

// in range excluding end
#define IN_RANGE_EXC(val,beg,end) \
  ((unsigned int)(val) - (unsigned int)(beg) <  (unsigned int)(end) - (unsigned int)(beg))

void cleanup (const char *cause, bool make_core = false);
void fork_abort (const char *msg);

// rationale for using (U) not (T) is to reduce signed/unsigned issues,
// as a is often a constant while b is the variable. it is still a bug, though.
template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; }

template<typename T> static inline void min_it (T &v, T m) { v = min (v, m); }
template<typename T> static inline void max_it (T &v, T m) { v = max (v, m); }
template<typename T> static inline void clamp_it (T &v, T a, T b) { v = clamp (v, a, b); }

template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }

template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }

// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
template<typename T> static inline T div    (T val, T div) { return (val + div / 2) / div; }
// div, round-up
template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; }
// div, round-down
template<typename T> static inline T div_rd (T val, T div) { return (val          ) / div; }

template<typename T>
static inline T
lerp (T val, T min_in, T max_in, T min_out, T max_out)
{
  return min_out + div   <T> ((val - min_in) * (max_out - min_out), max_in  - min_in);
}

// lerp, round-down
template<typename T>
static inline T
lerp_rd (T val, T min_in, T max_in, T min_out, T max_out)
{
  return min_out + div_rd<T> ((val - min_in) * (max_out - min_out), max_in  - min_in);
}

// lerp, round-up
template<typename T>
static inline T
lerp_ru (T val, T min_in, T max_in, T min_out, T max_out)
{
  return min_out + div_ru<T> ((val - min_in) * (max_out - min_out), max_in  - min_in);
}

// lots of stuff taken from FXT

/* Rotate right. This is used in various places for checksumming */
//TODO: that sucks, use a better checksum algo
static inline uint32_t
rotate_right (uint32_t c, uint32_t count = 1)
{
  return (c << (32 - count)) | (c >> count);
}

static inline uint32_t
rotate_left (uint32_t c, uint32_t count = 1)
{
  return (c >> (32 - count)) | (c << count);
}

// Return abs(a-b)
// Both a and b must not have the most significant bit set
static inline uint32_t
upos_abs_diff (uint32_t a, uint32_t b)
{
  long d1 = b - a;
  long d2 = (d1 & (d1 >> 31)) << 1;

  return d1 - d2;               // == (b - d) - (a + d);
}

// Both a and b must not have the most significant bit set
static inline uint32_t
upos_min (uint32_t a, uint32_t b)
{
  int32_t d = b - a;
  d &= d >> 31;
  return a + d;
}

// Both a and b must not have the most significant bit set
static inline uint32_t
upos_max (uint32_t a, uint32_t b)
{
  int32_t d = b - a;
  d &= d >> 31;
  return b - d;
}

// this is much faster than crossfires original algorithm
// on modern cpus
inline int
isqrt (int n)
{
  return (int)sqrtf ((float)n);
}

// this is only twice as fast as naive sqrtf (dx*dy+dy*dy)
#if 0
// and has a max. error of 6 in the range -100..+100.
#else
// and has a max. error of 9 in the range -100..+100.
#endif
inline int 
idistance (int dx, int dy)
{ 
  unsigned int dx_ = abs (dx);
  unsigned int dy_ = abs (dy);

#if 0
  return dx_ > dy_
      ? (dx_ * 61685 + dy_ * 26870) >> 16
      : (dy_ * 61685 + dx_ * 26870) >> 16;
#else
  return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
#endif
}

/*
 * absdir(int): Returns a number between 1 and 8, which represent
 * the "absolute" direction of a number (it actually takes care of
 * "overflow" in previous calculations of a direction).
 */
inline int
absdir (int d)
{
  return ((d - 1) & 7) + 1;
}

extern ssize_t slice_alloc; // statistics

void *salloc_ (int n)            throw (std::bad_alloc);
void *salloc_ (int n, void *src) throw (std::bad_alloc);

// strictly the same as g_slice_alloc, but never returns 0
template<typename T>
inline T *salloc (int n = 1)     throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T));              }

// also copies src into the new area, like "memdup"
// if src is 0, clears the memory
template<typename T>
inline T *salloc (int n, T *src) throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), (void *)src); }

// clears the memory
template<typename T>
inline T *salloc0(int n = 1)     throw (std::bad_alloc) { return (T *)salloc_ (n * sizeof (T), 0);           }

// for symmetry
template<typename T>
inline void sfree (T *ptr, int n = 1) throw ()
{
  if (expect_true (ptr))
    {
      slice_alloc -= n * sizeof (T);
      if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
      g_slice_free1 (n * sizeof (T), (void *)ptr);
      assert (slice_alloc >= 0);//D
    }
}

// nulls the pointer
template<typename T>
inline void sfree0 (T *&ptr, int n = 1) throw ()
{
  sfree<T> (ptr, n);
  ptr = 0;
}

// makes dynamically allocated objects zero-initialised
struct zero_initialised
{
  void *operator new (size_t s, void *p)
  {
    memset (p, 0, s);
    return p;
  }

  void *operator new (size_t s)
  {
    return salloc0<char> (s);
  }

  void *operator new[] (size_t s)
  {
    return salloc0<char> (s);
  }

  void operator delete (void *p, size_t s)
  {
    sfree ((char *)p, s);
  }

  void operator delete[] (void *p, size_t s)
  {
    sfree ((char *)p, s);
  }
};

// makes dynamically allocated objects zero-initialised
struct slice_allocated
{
  void *operator new (size_t s, void *p)
  {
    return p;
  }

  void *operator new (size_t s)
  {
    return salloc<char> (s);
  }

  void *operator new[] (size_t s)
  {
    return salloc<char> (s);
  }

  void operator delete (void *p, size_t s)
  {
    sfree ((char *)p, s);
  }

  void operator delete[] (void *p, size_t s)
  {
    sfree ((char *)p, s);
  }
};

// a STL-compatible allocator that uses g_slice
// boy, this is verbose
template<typename Tp>
struct slice_allocator
{
  typedef size_t size_type;
  typedef ptrdiff_t difference_type;
  typedef Tp *pointer;
  typedef const Tp *const_pointer;
  typedef Tp &reference;
  typedef const Tp &const_reference;
  typedef Tp value_type;

  template <class U> 
  struct rebind
  {
    typedef slice_allocator<U> other;
  };

  slice_allocator () throw () { }
  slice_allocator (const slice_allocator &) throw () { }
  template<typename Tp2>
  slice_allocator (const slice_allocator<Tp2> &) throw () { }

  ~slice_allocator () { }

  pointer address (reference x) const { return &x; }
  const_pointer address (const_reference x) const { return &x; }

  pointer allocate (size_type n, const_pointer = 0)
  {
    return salloc<Tp> (n);
  }

  void deallocate (pointer p, size_type n)
  {
    sfree<Tp> (p, n);
  }

  size_type max_size () const throw ()
  {
    return size_t (-1) / sizeof (Tp);
  }

  void construct (pointer p, const Tp &val)
  {
    ::new (p) Tp (val);
  }

  void destroy (pointer p)
  {
    p->~Tp ();
  }
};

// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
struct tausworthe_random_generator
{
  // generator
  uint32_t state [4];

  void operator =(const tausworthe_random_generator &src)
  {
    state [0] = src.state [0];
    state [1] = src.state [1];
    state [2] = src.state [2];
    state [3] = src.state [3];
  }

  void seed (uint32_t seed);
  uint32_t next ();

  // uniform distribution, 0 .. max (0, num - 1)
  uint32_t operator ()(uint32_t num)
  {
    return is_constant (num)
             ? (next () * (uint64_t)num) >> 32U
             : get_range (num);
  }

  // return a number within (min .. max)
  int operator () (int r_min, int r_max)
  {
    return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
              ? r_min + operator ()(r_max - r_min + 1)
              : get_range (r_min, r_max);
  }

  double operator ()()
  {
    return this->next () / (double)0xFFFFFFFFU;
  }

protected:
  uint32_t get_range (uint32_t r_max);
  int get_range (int r_min, int r_max);
};

typedef tausworthe_random_generator rand_gen;

extern rand_gen rndm, rmg_rndm;

INTERFACE_CLASS (attachable)
struct refcnt_base
{
  typedef int refcnt_t;
  mutable refcnt_t ACC (RW, refcnt);

  MTH void refcnt_inc () const { ++refcnt; }
  MTH void refcnt_dec () const { --refcnt; }

  refcnt_base () : refcnt (0) { }
};

// to avoid branches with more advanced compilers
extern refcnt_base::refcnt_t refcnt_dummy;

template<class T>
struct refptr
{
  // p if not null
  refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }

  void refcnt_dec ()
  {
    if (!is_constant (p))
      --*refcnt_ref ();
    else if (p)
      --p->refcnt;
  }

  void refcnt_inc ()
  {
    if (!is_constant (p))
      ++*refcnt_ref ();
    else if (p)
      ++p->refcnt;
  }

  T *p;

  refptr () : p(0) { }
  refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
  refptr (T *p) : p(p) { refcnt_inc (); }
  ~refptr () { refcnt_dec (); }

  const refptr<T> &operator =(T *o)
  {
    // if decrementing ever destroys we need to reverse the order here
    refcnt_dec ();
    p = o;
    refcnt_inc ();
    return *this;
  }

  const refptr<T> &operator =(const refptr<T> &o)
  {
    *this = o.p;
    return *this;
  }

  T &operator * () const { return *p; }
  T *operator ->() const { return  p; }

  operator T *() const { return p; }
};

typedef refptr<maptile>   maptile_ptr;
typedef refptr<object>    object_ptr;
typedef refptr<archetype> arch_ptr;
typedef refptr<client>    client_ptr;
typedef refptr<player>    player_ptr;

struct str_hash
{
  std::size_t operator ()(const char *s) const
  {
    unsigned long hash = 0;

    /* use the one-at-a-time hash function, which supposedly is
     * better than the djb2-like one used by perl5.005, but
     * certainly is better then the bug used here before.
     * see http://burtleburtle.net/bob/hash/doobs.html
     */
    while (*s)
      {
        hash += *s++;
        hash += hash << 10;
        hash ^= hash >>  6;
      }

    hash += hash <<  3;
    hash ^= hash >> 11;
    hash += hash << 15;

    return hash;
  }
};

struct str_equal
{
  bool operator ()(const char *a, const char *b) const
  {
    return !strcmp (a, b);
  }
};

// Mostly the same as std::vector, but insert/erase can reorder
// the elements, making append(=insert)/remove O(1) instead of O(n).
//
// NOTE: only some forms of erase are available
template<class T>
struct unordered_vector : std::vector<T, slice_allocator<T> >
{
  typedef typename unordered_vector::iterator iterator;

  void erase (unsigned int pos)
  {
    if (pos < this->size () - 1)
      (*this)[pos] = (*this)[this->size () - 1];

    this->pop_back ();
  }

  void erase (iterator i)
  {
    erase ((unsigned int )(i - this->begin ()));
  }
};

// This container blends advantages of linked lists
// (efficiency) with vectors (random access) by
// by using an unordered vector and storing the vector
// index inside the object.
//
// + memory-efficient on most 64 bit archs
// + O(1) insert/remove
// + free unique (but varying) id for inserted objects
// + cache-friendly iteration
// - only works for pointers to structs
//
// NOTE: only some forms of erase/insert are available
typedef int object_vector_index;

template<class T, object_vector_index T::*indexmember>
struct object_vector : std::vector<T *, slice_allocator<T *> >
{
  typedef typename object_vector::iterator iterator;

  bool contains (const T *obj) const
  {
    return obj->*indexmember;
  }

  iterator find (const T *obj)
  {
    return obj->*indexmember
      ? this->begin () + obj->*indexmember - 1
      : this->end ();
  }

  void push_back (T *obj)
  {
    std::vector<T *, slice_allocator<T *> >::push_back (obj);
    obj->*indexmember = this->size ();
  }

  void insert (T *obj)
  {
    push_back (obj);
  }

  void insert (T &obj)
  {
    insert (&obj);
  }

  void erase (T *obj)
  {
    unsigned int pos = obj->*indexmember;
    obj->*indexmember = 0;

    if (pos < this->size ())
      {
        (*this)[pos - 1] = (*this)[this->size () - 1];
        (*this)[pos - 1]->*indexmember = pos;
      }

    this->pop_back ();
  }

  void erase (T &obj)
  {
    erase (&obj);
  }
};

// basically does what strncpy should do, but appends "..." to strings exceeding length
void assign (char *dst, const char *src, int maxlen);

// type-safe version of assign
template<int N>
inline void assign (char (&dst)[N], const char *src)
{
  assign ((char *)&dst, src, N);
}

typedef double tstamp;

// return current time as timestamp
tstamp now ();

int similar_direction (int a, int b);

// like sprintf, but returns a "static" buffer
const char *format (const char *format, ...);

/////////////////////////////////////////////////////////////////////////////
// threads, very very thin wrappers around pthreads

struct thread
{
  pthread_t id;

  void start (void *(*start_routine)(void *), void *arg = 0);

  void cancel ()
  {
    pthread_cancel (id);
  }

  void *join ()
  {
    void *ret;

    if (pthread_join (id, &ret))
      cleanup ("pthread_join failed", 1);

    return ret;
  }
};

// note that mutexes are not classes
typedef pthread_mutex_t smutex;

#if __linux && defined (PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP)
 #define SMUTEX_INITIALISER PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
#else
 #define SMUTEX_INITIALISER PTHREAD_MUTEX_INITIALIZER
#endif

#define SMUTEX(name) smutex name = SMUTEX_INITIALISER
#define SMUTEX_LOCK(name)   pthread_mutex_lock   (&(name))
#define SMUTEX_UNLOCK(name) pthread_mutex_unlock (&(name))

typedef pthread_cond_t scond;

#define SCOND(name) scond name = PTHREAD_COND_INITIALIZER
#define SCOND_SIGNAL(name)     pthread_cond_signal    (&(name))
#define SCOND_BROADCAST(name)  pthread_cond_broadcast (&(name))
#define SCOND_WAIT(name,mutex) pthread_cond_wait      (&(name), &(mutex))

#endif

Revision:	1.78
Committed:	Thu Dec 4 03:48:19 2008 UTC (15 years, 5 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-2_72, rel-2_73
Changes since 1.77:	+28 -1 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	*
4	* Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	*
6	* Deliantra is free software: you can redistribute it and/or modify
7	* it under the terms of the GNU General Public License as published by
8	* the Free Software Foundation, either version 3 of the License, or
9	* (at your option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU General Public License
17	* along with this program. If not, see <http://www.gnu.org/licenses/>.
18	*
19	* The authors can be reached via e-mail to <support@deliantra.net>
20	*/
21
22	#ifndef UTIL_H__
23	#define UTIL_H__
24
25	#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
26	#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
27	#define PREFER_MALLOC 0 // use malloc and not the slice allocator
28
29	#if __GNUC__ >= 3
30	# define is_constant(c) __builtin_constant_p (c)
31	# define expect(expr,value) __builtin_expect ((expr),(value))
32	# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
33	#else
34	# define is_constant(c) 0
35	# define expect(expr,value) (expr)
36	# define prefetch(addr,rw,locality)
37	#endif
38
39	#if __GNUC__ < 4 \|\| (__GNUC__ == 4 \|\| __GNUC_MINOR__ < 4)
40	# define decltype(x) typeof(x)
41	#endif
42
43	// put into ifs if you are very sure that the expression
44	// is mostly true or mosty false. note that these return
45	// booleans, not the expression.
46	#define expect_false(expr) expect ((expr) != 0, 0)
47	#define expect_true(expr) expect ((expr) != 0, 1)
48
49	#include <pthread.h>
50
51	#include <cstddef>
52	#include <cmath>
53	#include <new>
54	#include <vector>
55
56	#include <glib.h>
57
58	#include <shstr.h>
59	#include <traits.h>
60
61	#if DEBUG_SALLOC
62	# define g_slice_alloc0(s) debug_slice_alloc0(s)
63	# define g_slice_alloc(s) debug_slice_alloc(s)
64	# define g_slice_free1(s,p) debug_slice_free1(s,p)
65	void *g_slice_alloc (unsigned long size);
66	void *g_slice_alloc0 (unsigned long size);
67	void g_slice_free1 (unsigned long size, void *ptr);
68	#elif PREFER_MALLOC
69	# define g_slice_alloc0(s) calloc (1, (s))
70	# define g_slice_alloc(s) malloc ((s))
71	# define g_slice_free1(s,p) free ((p))
72	#endif
73
74	// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
75	#define auto(var,expr) decltype(expr) var = (expr)
76
77	// very ugly macro that basicaly declares and initialises a variable
78	// that is in scope for the next statement only
79	// works only for stuff that can be assigned 0 and converts to false
80	// (note: works great for pointers)
81	// most ugly macro I ever wrote
82	#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
83
84	// in range including end
85	#define IN_RANGE_INC(val,beg,end) \
86	((unsigned int)(val) - (unsigned int)(beg) <= (unsigned int)(end) - (unsigned int)(beg))
87
88	// in range excluding end
89	#define IN_RANGE_EXC(val,beg,end) \
90	((unsigned int)(val) - (unsigned int)(beg) < (unsigned int)(end) - (unsigned int)(beg))
91
92	void cleanup (const char *cause, bool make_core = false);
93	void fork_abort (const char *msg);
94
95	// rationale for using (U) not (T) is to reduce signed/unsigned issues,
96	// as a is often a constant while b is the variable. it is still a bug, though.
97	template<typename T, typename U> static inline T min (T a, U b) { return (U)a < b ? (U)a : b; }
98	template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
99	template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; }
100
101	template<typename T> static inline void min_it (T &v, T m) { v = min (v, m); }
102	template<typename T> static inline void max_it (T &v, T m) { v = max (v, m); }
103	template<typename T> static inline void clamp_it (T &v, T a, T b) { v = clamp (v, a, b); }
104
105	template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
106
107	template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
108	template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
109
110	// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
111	template<typename T> static inline T div (T val, T div) { return (val + div / 2) / div; }
112	// div, round-up
113	template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; }
114	// div, round-down
115	template<typename T> static inline T div_rd (T val, T div) { return (val ) / div; }
116
117	template<typename T>
118	static inline T
119	lerp (T val, T min_in, T max_in, T min_out, T max_out)
120	{
121	return min_out + div <T> ((val - min_in) * (max_out - min_out), max_in - min_in);
122	}
123
124	// lerp, round-down
125	template<typename T>
126	static inline T
127	lerp_rd (T val, T min_in, T max_in, T min_out, T max_out)
128	{
129	return min_out + div_rd<T> ((val - min_in) * (max_out - min_out), max_in - min_in);
130	}
131
132	// lerp, round-up
133	template<typename T>
134	static inline T
135	lerp_ru (T val, T min_in, T max_in, T min_out, T max_out)
136	{
137	return min_out + div_ru<T> ((val - min_in) * (max_out - min_out), max_in - min_in);
138	}
139
140	// lots of stuff taken from FXT
141
142	/* Rotate right. This is used in various places for checksumming */
143	//TODO: that sucks, use a better checksum algo
144	static inline uint32_t
145	rotate_right (uint32_t c, uint32_t count = 1)
146	{
147	return (c << (32 - count)) \| (c >> count);
148	}
149
150	static inline uint32_t
151	rotate_left (uint32_t c, uint32_t count = 1)
152	{
153	return (c >> (32 - count)) \| (c << count);
154	}
155
156	// Return abs(a-b)
157	// Both a and b must not have the most significant bit set
158	static inline uint32_t
159	upos_abs_diff (uint32_t a, uint32_t b)
160	{
161	long d1 = b - a;
162	long d2 = (d1 & (d1 >> 31)) << 1;
163
164	return d1 - d2; // == (b - d) - (a + d);
165	}
166
167	// Both a and b must not have the most significant bit set
168	static inline uint32_t
169	upos_min (uint32_t a, uint32_t b)
170	{
171	int32_t d = b - a;
172	d &= d >> 31;
173	return a + d;
174	}
175
176	// Both a and b must not have the most significant bit set
177	static inline uint32_t
178	upos_max (uint32_t a, uint32_t b)
179	{
180	int32_t d = b - a;
181	d &= d >> 31;
182	return b - d;
183	}
184
185	// this is much faster than crossfires original algorithm
186	// on modern cpus
187	inline int
188	isqrt (int n)
189	{
190	return (int)sqrtf ((float)n);
191	}
192
193	// this is only twice as fast as naive sqrtf (dxdy+dydy)
194	#if 0
195	// and has a max. error of 6 in the range -100..+100.
196	#else
197	// and has a max. error of 9 in the range -100..+100.
198	#endif
199	inline int
200	idistance (int dx, int dy)
201	{
202	unsigned int dx_ = abs (dx);
203	unsigned int dy_ = abs (dy);
204
205	#if 0
206	return dx_ > dy_
207	? (dx_ * 61685 + dy_ * 26870) >> 16
208	: (dy_ * 61685 + dx_ * 26870) >> 16;
209	#else
210	return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
211	#endif
212	}
213
214	/*
215	* absdir(int): Returns a number between 1 and 8, which represent
216	* the "absolute" direction of a number (it actually takes care of
217	* "overflow" in previous calculations of a direction).
218	*/
219	inline int
220	absdir (int d)
221	{
222	return ((d - 1) & 7) + 1;
223	}
224
225	extern ssize_t slice_alloc; // statistics
226
227	void *salloc_ (int n) throw (std::bad_alloc);
228	void salloc_ (int n, void src) throw (std::bad_alloc);
229
230	// strictly the same as g_slice_alloc, but never returns 0
231	template<typename T>
232	inline T salloc (int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T)); }
233
234	// also copies src into the new area, like "memdup"
235	// if src is 0, clears the memory
236	template<typename T>
237	inline T salloc (int n, T src) throw (std::bad_alloc) { return (T )salloc_ (n sizeof (T), (void *)src); }
238
239	// clears the memory
240	template<typename T>
241	inline T salloc0(int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T), 0); }
242
243	// for symmetry
244	template<typename T>
245	inline void sfree (T *ptr, int n = 1) throw ()
246	{
247	if (expect_true (ptr))
248	{
249	slice_alloc -= n * sizeof (T);
250	if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
251	g_slice_free1 (n * sizeof (T), (void *)ptr);
252	assert (slice_alloc >= 0);//D
253	}
254	}
255
256	// nulls the pointer
257	template<typename T>
258	inline void sfree0 (T *&ptr, int n = 1) throw ()
259	{
260	sfree<T> (ptr, n);
261	ptr = 0;
262	}
263
264	// makes dynamically allocated objects zero-initialised
265	struct zero_initialised
266	{
267	void operator new (size_t s, void p)
268	{
269	memset (p, 0, s);
270	return p;
271	}
272
273	void *operator new (size_t s)
274	{
275	return salloc0<char> (s);
276	}
277
278	void *operator new[] (size_t s)
279	{
280	return salloc0<char> (s);
281	}
282
283	void operator delete (void *p, size_t s)
284	{
285	sfree ((char *)p, s);
286	}
287
288	void operator delete[] (void *p, size_t s)
289	{
290	sfree ((char *)p, s);
291	}
292	};
293
294	// makes dynamically allocated objects zero-initialised
295	struct slice_allocated
296	{
297	void operator new (size_t s, void p)
298	{
299	return p;
300	}
301
302	void *operator new (size_t s)
303	{
304	return salloc<char> (s);
305	}
306
307	void *operator new[] (size_t s)
308	{
309	return salloc<char> (s);
310	}
311
312	void operator delete (void *p, size_t s)
313	{
314	sfree ((char *)p, s);
315	}
316
317	void operator delete[] (void *p, size_t s)
318	{
319	sfree ((char *)p, s);
320	}
321	};
322
323	// a STL-compatible allocator that uses g_slice
324	// boy, this is verbose
325	template<typename Tp>
326	struct slice_allocator
327	{
328	typedef size_t size_type;
329	typedef ptrdiff_t difference_type;
330	typedef Tp *pointer;
331	typedef const Tp *const_pointer;
332	typedef Tp &reference;
333	typedef const Tp &const_reference;
334	typedef Tp value_type;
335
336	template <class U>
337	struct rebind
338	{
339	typedef slice_allocator<U> other;
340	};
341
342	slice_allocator () throw () { }
343	slice_allocator (const slice_allocator &) throw () { }
344	template<typename Tp2>
345	slice_allocator (const slice_allocator<Tp2> &) throw () { }
346
347	~slice_allocator () { }
348
349	pointer address (reference x) const { return &x; }
350	const_pointer address (const_reference x) const { return &x; }
351
352	pointer allocate (size_type n, const_pointer = 0)
353	{
354	return salloc<Tp> (n);
355	}
356
357	void deallocate (pointer p, size_type n)
358	{
359	sfree<Tp> (p, n);
360	}
361
362	size_type max_size () const throw ()
363	{
364	return size_t (-1) / sizeof (Tp);
365	}
366
367	void construct (pointer p, const Tp &val)
368	{
369	::new (p) Tp (val);
370	}
371
372	void destroy (pointer p)
373	{
374	p->~Tp ();
375	}
376	};
377
378	// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
379	// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
380	// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
381	struct tausworthe_random_generator
382	{
383	// generator
384	uint32_t state [4];
385
386	void operator =(const tausworthe_random_generator &src)
387	{
388	state [0] = src.state [0];
389	state [1] = src.state [1];
390	state [2] = src.state [2];
391	state [3] = src.state [3];
392	}
393
394	void seed (uint32_t seed);
395	uint32_t next ();
396
397	// uniform distribution, 0 .. max (0, num - 1)
398	uint32_t operator ()(uint32_t num)
399	{
400	return is_constant (num)
401	? (next () * (uint64_t)num) >> 32U
402	: get_range (num);
403	}
404
405	// return a number within (min .. max)
406	int operator () (int r_min, int r_max)
407	{
408	return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
409	? r_min + operator ()(r_max - r_min + 1)
410	: get_range (r_min, r_max);
411	}
412
413	double operator ()()
414	{
415	return this->next () / (double)0xFFFFFFFFU;
416	}
417
418	protected:
419	uint32_t get_range (uint32_t r_max);
420	int get_range (int r_min, int r_max);
421	};
422
423	typedef tausworthe_random_generator rand_gen;
424
425	extern rand_gen rndm, rmg_rndm;
426
427	INTERFACE_CLASS (attachable)
428	struct refcnt_base
429	{
430	typedef int refcnt_t;
431	mutable refcnt_t ACC (RW, refcnt);
432
433	MTH void refcnt_inc () const { ++refcnt; }
434	MTH void refcnt_dec () const { --refcnt; }
435
436	refcnt_base () : refcnt (0) { }
437	};
438
439	// to avoid branches with more advanced compilers
440	extern refcnt_base::refcnt_t refcnt_dummy;
441
442	template<class T>
443	struct refptr
444	{
445	// p if not null
446	refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
447
448	void refcnt_dec ()
449	{
450	if (!is_constant (p))
451	--*refcnt_ref ();
452	else if (p)
453	--p->refcnt;
454	}
455
456	void refcnt_inc ()
457	{
458	if (!is_constant (p))
459	++*refcnt_ref ();
460	else if (p)
461	++p->refcnt;
462	}
463
464	T *p;
465
466	refptr () : p(0) { }
467	refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
468	refptr (T *p) : p(p) { refcnt_inc (); }
469	~refptr () { refcnt_dec (); }
470
471	const refptr<T> &operator =(T *o)
472	{
473	// if decrementing ever destroys we need to reverse the order here
474	refcnt_dec ();
475	p = o;
476	refcnt_inc ();
477	return *this;
478	}
479
480	const refptr<T> &operator =(const refptr<T> &o)
481	{
482	*this = o.p;
483	return *this;
484	}
485
486	T &operator * () const { return *p; }
487	T *operator ->() const { return p; }
488
489	operator T *() const { return p; }
490	};
491
492	typedef refptr<maptile> maptile_ptr;
493	typedef refptr<object> object_ptr;
494	typedef refptr<archetype> arch_ptr;
495	typedef refptr<client> client_ptr;
496	typedef refptr<player> player_ptr;
497
498	struct str_hash
499	{
500	std::size_t operator ()(const char *s) const
501	{
502	unsigned long hash = 0;
503
504	/* use the one-at-a-time hash function, which supposedly is
505	* better than the djb2-like one used by perl5.005, but
506	* certainly is better then the bug used here before.
507	* see http://burtleburtle.net/bob/hash/doobs.html
508	*/
509	while (*s)
510	{
511	hash += *s++;
512	hash += hash << 10;
513	hash ^= hash >> 6;
514	}
515
516	hash += hash << 3;
517	hash ^= hash >> 11;
518	hash += hash << 15;
519
520	return hash;
521	}
522	};
523
524	struct str_equal
525	{
526	bool operator ()(const char a, const char b) const
527	{
528	return !strcmp (a, b);
529	}
530	};
531
532	// Mostly the same as std::vector, but insert/erase can reorder
533	// the elements, making append(=insert)/remove O(1) instead of O(n).
534	//
535	// NOTE: only some forms of erase are available
536	template<class T>
537	struct unordered_vector : std::vector<T, slice_allocator<T> >
538	{
539	typedef typename unordered_vector::iterator iterator;
540
541	void erase (unsigned int pos)
542	{
543	if (pos < this->size () - 1)
544	(this)[pos] = (this)[this->size () - 1];
545
546	this->pop_back ();
547	}
548
549	void erase (iterator i)
550	{
551	erase ((unsigned int )(i - this->begin ()));
552	}
553	};
554
555	// This container blends advantages of linked lists
556	// (efficiency) with vectors (random access) by
557	// by using an unordered vector and storing the vector
558	// index inside the object.
559	//
560	// + memory-efficient on most 64 bit archs
561	// + O(1) insert/remove
562	// + free unique (but varying) id for inserted objects
563	// + cache-friendly iteration
564	// - only works for pointers to structs
565	//
566	// NOTE: only some forms of erase/insert are available
567	typedef int object_vector_index;
568
569	template<class T, object_vector_index T::*indexmember>
570	struct object_vector : std::vector<T , slice_allocator<T > >
571	{
572	typedef typename object_vector::iterator iterator;
573
574	bool contains (const T *obj) const
575	{
576	return obj->*indexmember;
577	}
578
579	iterator find (const T *obj)
580	{
581	return obj->*indexmember
582	? this->begin () + obj->*indexmember - 1
583	: this->end ();
584	}
585
586	void push_back (T *obj)
587	{
588	std::vector<T , slice_allocator<T > >::push_back (obj);
589	obj->*indexmember = this->size ();
590	}
591
592	void insert (T *obj)
593	{
594	push_back (obj);
595	}
596
597	void insert (T &obj)
598	{
599	insert (&obj);
600	}
601
602	void erase (T *obj)
603	{
604	unsigned int pos = obj->*indexmember;
605	obj->*indexmember = 0;
606
607	if (pos < this->size ())
608	{
609	(this)[pos - 1] = (this)[this->size () - 1];
610	(this)[pos - 1]->indexmember = pos;
611	}
612
613	this->pop_back ();
614	}
615
616	void erase (T &obj)
617	{
618	erase (&obj);
619	}
620	};
621
622	// basically does what strncpy should do, but appends "..." to strings exceeding length
623	void assign (char dst, const char src, int maxlen);
624
625	// type-safe version of assign
626	template<int N>
627	inline void assign (char (&dst)[N], const char *src)
628	{
629	assign ((char *)&dst, src, N);
630	}
631
632	typedef double tstamp;
633
634	// return current time as timestamp
635	tstamp now ();
636
637	int similar_direction (int a, int b);
638
639	// like sprintf, but returns a "static" buffer
640	const char format (const char format, ...);
641
642	/////////////////////////////////////////////////////////////////////////////
643	// threads, very very thin wrappers around pthreads
644
645	struct thread
646	{
647	pthread_t id;
648
649	void start (void (start_routine)(void ), void arg = 0);
650
651	void cancel ()
652	{
653	pthread_cancel (id);
654	}
655
656	void *join ()
657	{
658	void *ret;
659
660	if (pthread_join (id, &ret))
661	cleanup ("pthread_join failed", 1);
662
663	return ret;
664	}
665	};
666
667	// note that mutexes are not classes
668	typedef pthread_mutex_t smutex;
669
670	#if __linux && defined (PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP)
671	#define SMUTEX_INITIALISER PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
672	#else
673	#define SMUTEX_INITIALISER PTHREAD_MUTEX_INITIALIZER
674	#endif
675
676	#define SMUTEX(name) smutex name = SMUTEX_INITIALISER
677	#define SMUTEX_LOCK(name) pthread_mutex_lock (&(name))
678	#define SMUTEX_UNLOCK(name) pthread_mutex_unlock (&(name))
679
680	typedef pthread_cond_t scond;
681
682	#define SCOND(name) scond name = PTHREAD_COND_INITIALIZER
683	#define SCOND_SIGNAL(name) pthread_cond_signal (&(name))
684	#define SCOND_BROADCAST(name) pthread_cond_broadcast (&(name))
685	#define SCOND_WAIT(name,mutex) pthread_cond_wait (&(name), &(mutex))
686
687	#endif
688