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, 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)); }

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

// 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
  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:	1.75
Committed:	Tue May 6 16:55:26 2008 UTC (16 years ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.74:	+1 -1 lines
Log Message:	update copyright
#	User	Rev	Content
1	root	1.46	/*
2	root	1.58	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	root	1.46	*
4	root	1.75	* Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	root	1.46	*
6	root	1.58	* Deliantra is free software: you can redistribute it and/or modify
7	root	1.51	* 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	root	1.46	*
11	root	1.51	* 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	root	1.46	*
16	root	1.51	* 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	root	1.46	*
19	root	1.58	* The authors can be reached via e-mail to <support@deliantra.net>
20	root	1.46	*/
21
22	root	1.1	#ifndef UTIL_H__
23			#define UTIL_H__
24
25	root	1.71	#define DEBUG_POISON 0x00 // poison memory before freeing it if != 0
26	root	1.70	#define DEBUG_SALLOC 0 // add a debug wrapper around all sallocs
27			#define PREFER_MALLOC 0 // use malloc and not the slice allocator
28	root	1.36
29	root	1.2	#if __GNUC__ >= 3
30	root	1.45	# 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	root	1.2	#else
34	root	1.45	# define is_constant(c) 0
35			# define expect(expr,value) (expr)
36			# define prefetch(addr,rw,locality)
37	root	1.2	#endif
38
39	root	1.47	#if __GNUC__ < 4 \|\| (__GNUC__ == 4 \|\| __GNUC_MINOR__ < 4)
40			# define decltype(x) typeof(x)
41			#endif
42
43	root	1.45	// 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	root	1.66	#include <pthread.h>
50
51	root	1.11	#include <cstddef>
52	root	1.28	#include <cmath>
53	root	1.25	#include <new>
54			#include <vector>
55	root	1.11
56			#include <glib.h>
57
58	root	1.25	#include <shstr.h>
59			#include <traits.h>
60
61	root	1.65	#if DEBUG_SALLOC
62	root	1.60	# 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	root	1.67	#elif PREFER_MALLOC
69			# define g_slice_alloc0(s) calloc (1, (s))
70			# define g_slice_alloc(s) malloc ((s))
71	root	1.68	# define g_slice_free1(s,p) free ((p))
72	root	1.60	#endif
73
74	root	1.49	// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
75	root	1.47	#define auto(var,expr) decltype(expr) var = (expr)
76	root	1.14
77	root	1.26	// 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	root	1.48	#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
83	root	1.26
84	root	1.27	// 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	root	1.66	void cleanup (const char *cause, bool make_core = false);
93	root	1.31	void fork_abort (const char *msg);
94
95	root	1.35	// 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	root	1.32
101			template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
102
103	root	1.63	template<typename T, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
104			template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
105
106	root	1.44	template<typename T>
107			static inline T
108			lerp (T val, T min_in, T max_in, T min_out, T max_out)
109			{
110			return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
111			}
112
113	root	1.37	// lots of stuff taken from FXT
114
115			/* Rotate right. This is used in various places for checksumming */
116	root	1.38	//TODO: that sucks, use a better checksum algo
117	root	1.37	static inline uint32_t
118	root	1.38	rotate_right (uint32_t c, uint32_t count = 1)
119	root	1.37	{
120	root	1.38	return (c << (32 - count)) \| (c >> count);
121			}
122
123			static inline uint32_t
124			rotate_left (uint32_t c, uint32_t count = 1)
125			{
126			return (c >> (32 - count)) \| (c << count);
127	root	1.37	}
128
129			// Return abs(a-b)
130			// Both a and b must not have the most significant bit set
131			static inline uint32_t
132			upos_abs_diff (uint32_t a, uint32_t b)
133			{
134			long d1 = b - a;
135			long d2 = (d1 & (d1 >> 31)) << 1;
136
137			return d1 - d2; // == (b - d) - (a + d);
138			}
139
140			// Both a and b must not have the most significant bit set
141			static inline uint32_t
142			upos_min (uint32_t a, uint32_t b)
143			{
144			int32_t d = b - a;
145			d &= d >> 31;
146			return a + d;
147			}
148
149			// Both a and b must not have the most significant bit set
150			static inline uint32_t
151			upos_max (uint32_t a, uint32_t b)
152			{
153			int32_t d = b - a;
154			d &= d >> 31;
155			return b - d;
156			}
157
158	root	1.28	// this is much faster than crossfires original algorithm
159			// on modern cpus
160			inline int
161			isqrt (int n)
162			{
163			return (int)sqrtf ((float)n);
164			}
165
166			// this is only twice as fast as naive sqrtf (dxdy+dydy)
167			#if 0
168			// and has a max. error of 6 in the range -100..+100.
169			#else
170			// and has a max. error of 9 in the range -100..+100.
171			#endif
172			inline int
173			idistance (int dx, int dy)
174			{
175			unsigned int dx_ = abs (dx);
176			unsigned int dy_ = abs (dy);
177
178			#if 0
179			return dx_ > dy_
180			? (dx_ * 61685 + dy_ * 26870) >> 16
181			: (dy_ * 61685 + dx_ * 26870) >> 16;
182			#else
183	root	1.30	return dx_ + dy_ - min (dx_, dy_) * 5 / 8;
184	root	1.28	#endif
185			}
186
187	root	1.29	/*
188			* absdir(int): Returns a number between 1 and 8, which represent
189			* the "absolute" direction of a number (it actually takes care of
190			* "overflow" in previous calculations of a direction).
191			*/
192			inline int
193			absdir (int d)
194			{
195			return ((d - 1) & 7) + 1;
196			}
197	root	1.28
198	root	1.67	extern ssize_t slice_alloc; // statistics
199
200			void *salloc_ (int n) throw (std::bad_alloc);
201			void salloc_ (int n, void src) throw (std::bad_alloc);
202
203			// strictly the same as g_slice_alloc, but never returns 0
204			template<typename T>
205			inline T salloc (int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T)); }
206
207			// also copies src into the new area, like "memdup"
208			// if src is 0, clears the memory
209			template<typename T>
210			inline T salloc (int n, T src) throw (std::bad_alloc) { return (T )salloc_ (n sizeof (T), (void *)src); }
211
212			// clears the memory
213			template<typename T>
214			inline T salloc0(int n = 1) throw (std::bad_alloc) { return (T )salloc_ (n * sizeof (T), 0); }
215
216			// for symmetry
217			template<typename T>
218			inline void sfree (T *ptr, int n = 1) throw ()
219			{
220			if (expect_true (ptr))
221			{
222			slice_alloc -= n * sizeof (T);
223	root	1.70	if (DEBUG_POISON) memset (ptr, DEBUG_POISON, n * sizeof (T));
224	root	1.67	g_slice_free1 (n * sizeof (T), (void *)ptr);
225			assert (slice_alloc >= 0);//D
226			}
227			}
228	root	1.57
229	root	1.72	// nulls the pointer
230			template<typename T>
231			inline void sfree0 (T *&ptr, int n = 1) throw ()
232			{
233			sfree<T> (ptr, n);
234			ptr = 0;
235			}
236
237	root	1.1	// makes dynamically allocated objects zero-initialised
238			struct zero_initialised
239			{
240	root	1.11	void operator new (size_t s, void p)
241			{
242			memset (p, 0, s);
243			return p;
244			}
245
246			void *operator new (size_t s)
247			{
248	root	1.67	return salloc0<char> (s);
249	root	1.11	}
250
251			void *operator new[] (size_t s)
252			{
253	root	1.67	return salloc0<char> (s);
254	root	1.11	}
255
256			void operator delete (void *p, size_t s)
257			{
258	root	1.67	sfree ((char *)p, s);
259	root	1.11	}
260
261			void operator delete[] (void *p, size_t s)
262			{
263	root	1.67	sfree ((char *)p, s);
264	root	1.11	}
265			};
266
267	root	1.73	// makes dynamically allocated objects zero-initialised
268			struct slice_allocated
269			{
270			void operator new (size_t s, void p)
271			{
272			return p;
273			}
274
275			void *operator new (size_t s)
276			{
277			return salloc<char> (s);
278			}
279
280			void *operator new[] (size_t s)
281			{
282			return salloc<char> (s);
283			}
284
285			void operator delete (void *p, size_t s)
286			{
287			sfree ((char *)p, s);
288			}
289
290			void operator delete[] (void *p, size_t s)
291			{
292			sfree ((char *)p, s);
293			}
294			};
295
296	root	1.11	// a STL-compatible allocator that uses g_slice
297			// boy, this is verbose
298			template<typename Tp>
299			struct slice_allocator
300			{
301			typedef size_t size_type;
302			typedef ptrdiff_t difference_type;
303			typedef Tp *pointer;
304			typedef const Tp *const_pointer;
305			typedef Tp &reference;
306			typedef const Tp &const_reference;
307			typedef Tp value_type;
308
309			template <class U>
310			struct rebind
311			{
312			typedef slice_allocator<U> other;
313			};
314
315			slice_allocator () throw () { }
316	root	1.64	slice_allocator (const slice_allocator &) throw () { }
317	root	1.11	template<typename Tp2>
318			slice_allocator (const slice_allocator<Tp2> &) throw () { }
319
320			~slice_allocator () { }
321
322			pointer address (reference x) const { return &x; }
323			const_pointer address (const_reference x) const { return &x; }
324
325			pointer allocate (size_type n, const_pointer = 0)
326			{
327	root	1.18	return salloc<Tp> (n);
328	root	1.11	}
329
330			void deallocate (pointer p, size_type n)
331			{
332	root	1.19	sfree<Tp> (p, n);
333	root	1.11	}
334
335	root	1.64	size_type max_size () const throw ()
336	root	1.11	{
337			return size_t (-1) / sizeof (Tp);
338			}
339
340			void construct (pointer p, const Tp &val)
341			{
342			::new (p) Tp (val);
343			}
344
345			void destroy (pointer p)
346			{
347			p->~Tp ();
348			}
349	root	1.1	};
350
351	root	1.32	// P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213.
352			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
353			// http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps
354			struct tausworthe_random_generator
355			{
356	root	1.34	// generator
357	root	1.32	uint32_t state [4];
358
359	root	1.34	void operator =(const tausworthe_random_generator &src)
360			{
361			state [0] = src.state [0];
362			state [1] = src.state [1];
363			state [2] = src.state [2];
364			state [3] = src.state [3];
365			}
366
367			void seed (uint32_t seed);
368	root	1.32	uint32_t next ();
369
370	root	1.34	// uniform distribution
371	root	1.42	uint32_t operator ()(uint32_t num)
372	root	1.32	{
373	root	1.42	return is_constant (num)
374			? (next () * (uint64_t)num) >> 32U
375			: get_range (num);
376	root	1.32	}
377
378			// return a number within (min .. max)
379			int operator () (int r_min, int r_max)
380			{
381	root	1.42	return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
382			? r_min + operator ()(r_max - r_min + 1)
383	root	1.34	: get_range (r_min, r_max);
384	root	1.32	}
385
386			double operator ()()
387			{
388	root	1.34	return this->next () / (double)0xFFFFFFFFU;
389	root	1.32	}
390	root	1.34
391			protected:
392			uint32_t get_range (uint32_t r_max);
393			int get_range (int r_min, int r_max);
394	root	1.32	};
395
396			typedef tausworthe_random_generator rand_gen;
397
398	root	1.74	extern rand_gen rndm, rmg_rndm;
399	root	1.32
400	root	1.54	INTERFACE_CLASS (attachable)
401			struct refcnt_base
402			{
403			typedef int refcnt_t;
404			mutable refcnt_t ACC (RW, refcnt);
405
406			MTH void refcnt_inc () const { ++refcnt; }
407			MTH void refcnt_dec () const { --refcnt; }
408
409			refcnt_base () : refcnt (0) { }
410			};
411
412	root	1.56	// to avoid branches with more advanced compilers
413	root	1.54	extern refcnt_base::refcnt_t refcnt_dummy;
414
415	root	1.7	template<class T>
416			struct refptr
417			{
418	root	1.54	// p if not null
419			refcnt_base::refcnt_t *refcnt_ref () { return p ? &p->refcnt : &refcnt_dummy; }
420
421			void refcnt_dec ()
422			{
423			if (!is_constant (p))
424			--*refcnt_ref ();
425			else if (p)
426			--p->refcnt;
427			}
428
429			void refcnt_inc ()
430			{
431			if (!is_constant (p))
432			++*refcnt_ref ();
433			else if (p)
434			++p->refcnt;
435			}
436
437	root	1.7	T *p;
438
439			refptr () : p(0) { }
440	root	1.54	refptr (const refptr<T> &p) : p(p.p) { refcnt_inc (); }
441			refptr (T *p) : p(p) { refcnt_inc (); }
442			~refptr () { refcnt_dec (); }
443	root	1.7
444			const refptr<T> &operator =(T *o)
445			{
446	root	1.54	// if decrementing ever destroys we need to reverse the order here
447			refcnt_dec ();
448	root	1.7	p = o;
449	root	1.54	refcnt_inc ();
450	root	1.7	return *this;
451			}
452
453	root	1.54	const refptr<T> &operator =(const refptr<T> &o)
454	root	1.7	{
455			*this = o.p;
456			return *this;
457			}
458
459			T &operator * () const { return *p; }
460	root	1.54	T *operator ->() const { return p; }
461	root	1.7
462			operator T *() const { return p; }
463			};
464
465	root	1.24	typedef refptr<maptile> maptile_ptr;
466	root	1.22	typedef refptr<object> object_ptr;
467			typedef refptr<archetype> arch_ptr;
468	root	1.24	typedef refptr<client> client_ptr;
469			typedef refptr<player> player_ptr;
470	root	1.22
471	root	1.4	struct str_hash
472			{
473			std::size_t operator ()(const char *s) const
474			{
475			unsigned long hash = 0;
476
477			/* use the one-at-a-time hash function, which supposedly is
478			* better than the djb2-like one used by perl5.005, but
479			* certainly is better then the bug used here before.
480			* see http://burtleburtle.net/bob/hash/doobs.html
481			*/
482			while (*s)
483			{
484			hash += *s++;
485			hash += hash << 10;
486			hash ^= hash >> 6;
487			}
488
489			hash += hash << 3;
490			hash ^= hash >> 11;
491			hash += hash << 15;
492
493			return hash;
494			}
495			};
496
497			struct str_equal
498			{
499			bool operator ()(const char a, const char b) const
500			{
501			return !strcmp (a, b);
502			}
503			};
504
505	root	1.49	// Mostly the same as std::vector, but insert/erase can reorder
506	root	1.52	// the elements, making append(=insert)/remove O(1) instead of O(n).
507	root	1.49	//
508	root	1.52	// NOTE: only some forms of erase are available
509	root	1.26	template<class T>
510			struct unordered_vector : std::vector<T, slice_allocator<T> >
511	root	1.6	{
512	root	1.11	typedef typename unordered_vector::iterator iterator;
513	root	1.6
514			void erase (unsigned int pos)
515			{
516			if (pos < this->size () - 1)
517			(this)[pos] = (this)[this->size () - 1];
518
519			this->pop_back ();
520			}
521
522			void erase (iterator i)
523			{
524			erase ((unsigned int )(i - this->begin ()));
525			}
526			};
527
528	root	1.49	// This container blends advantages of linked lists
529			// (efficiency) with vectors (random access) by
530			// by using an unordered vector and storing the vector
531			// index inside the object.
532			//
533			// + memory-efficient on most 64 bit archs
534			// + O(1) insert/remove
535			// + free unique (but varying) id for inserted objects
536			// + cache-friendly iteration
537			// - only works for pointers to structs
538			//
539			// NOTE: only some forms of erase/insert are available
540	root	1.50	typedef int object_vector_index;
541
542			template<class T, object_vector_index T::*indexmember>
543	root	1.26	struct object_vector : std::vector<T , slice_allocator<T > >
544			{
545	root	1.48	typedef typename object_vector::iterator iterator;
546
547			bool contains (const T *obj) const
548			{
549	root	1.50	return obj->*indexmember;
550	root	1.48	}
551
552			iterator find (const T *obj)
553			{
554	root	1.50	return obj->*indexmember
555			? this->begin () + obj->*indexmember - 1
556	root	1.48	: this->end ();
557			}
558
559	root	1.53	void push_back (T *obj)
560			{
561			std::vector<T , slice_allocator<T > >::push_back (obj);
562			obj->*indexmember = this->size ();
563			}
564
565	root	1.26	void insert (T *obj)
566			{
567			push_back (obj);
568			}
569
570			void insert (T &obj)
571			{
572			insert (&obj);
573			}
574
575			void erase (T *obj)
576			{
577	root	1.50	unsigned int pos = obj->*indexmember;
578			obj->*indexmember = 0;
579	root	1.26
580			if (pos < this->size ())
581			{
582			(this)[pos - 1] = (this)[this->size () - 1];
583	root	1.50	(this)[pos - 1]->indexmember = pos;
584	root	1.26	}
585
586			this->pop_back ();
587			}
588
589			void erase (T &obj)
590			{
591	root	1.50	erase (&obj);
592	root	1.26	}
593			};
594
595	root	1.10	// basically does what strncpy should do, but appends "..." to strings exceeding length
596			void assign (char dst, const char src, int maxlen);
597
598			// type-safe version of assign
599	root	1.9	template<int N>
600			inline void assign (char (&dst)[N], const char *src)
601			{
602	root	1.10	assign ((char *)&dst, src, N);
603	root	1.9	}
604
605	root	1.17	typedef double tstamp;
606
607	root	1.59	// return current time as timestamp
608	root	1.17	tstamp now ();
609
610	root	1.25	int similar_direction (int a, int b);
611
612	root	1.55	// like sprintf, but returns a "static" buffer
613			const char format (const char format, ...);
614	root	1.43
615	root	1.66	/////////////////////////////////////////////////////////////////////////////
616			// threads, very very thin wrappers around pthreads
617
618			struct thread
619			{
620			pthread_t id;
621
622			void start (void (start_routine)(void ), void arg = 0);
623
624			void cancel ()
625			{
626			pthread_cancel (id);
627			}
628
629			void *join ()
630			{
631			void *ret;
632
633			if (pthread_join (id, &ret))
634			cleanup ("pthread_join failed", 1);
635
636			return ret;
637			}
638			};
639
640			// note that mutexes are not classes
641			typedef pthread_mutex_t smutex;
642
643			#if __linux && defined (PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP)
644			#define SMUTEX_INITIALISER PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
645			#else
646			#define SMUTEX_INITIALISER PTHREAD_MUTEX_INITIALIZER
647			#endif
648
649			#define SMUTEX(name) smutex name = SMUTEX_INITIALISER
650	root	1.68	#define SMUTEX_LOCK(name) pthread_mutex_lock (&(name))
651	root	1.66	#define SMUTEX_UNLOCK(name) pthread_mutex_unlock (&(name))
652
653	root	1.68	typedef pthread_cond_t scond;
654
655			#define SCOND(name) scond name = PTHREAD_COND_INITIALIZER
656			#define SCOND_SIGNAL(name) pthread_cond_signal (&(name))
657			#define SCOND_BROADCAST(name) pthread_cond_broadcast (&(name))
658			#define SCOND_WAIT(name,mutex) pthread_cond_wait (&(name), &(mutex))
659
660	root	1.1	#endif
661