--- deliantra/server/include/util.h	2007/01/19 15:15:50	1.34
+++ deliantra/server/include/util.h	2007/06/04 13:04:00	1.49
@@ -1,12 +1,50 @@
+/*
+ * This file is part of Crossfire TRT, the Multiplayer Online Role Playing Game.
+ * 
+ * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
+ * 
+ * Crossfire TRT 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 2 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 Crossfire TRT; if not, write to the Free Software Foundation, Inc. 51
+ * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ * 
+ * The authors can be reached via e-mail to <crossfire@schmorp.de>
+ */
+
 #ifndef UTIL_H__
 #define UTIL_H__
 
+//#define PREFER_MALLOC
+
 #if __GNUC__ >= 3
-# define is_constant(c) __builtin_constant_p (c)
+# 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 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 <cstddef>
 #include <cmath>
 #include <new>
@@ -17,15 +55,15 @@
 #include <shstr.h>
 #include <traits.h>
 
-// use a gcc extension for auto declarations until ISO C++ sanctifies them
-#define AUTODECL(var,expr) typeof(expr) var = (expr)
+// 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 declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
+#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) \
@@ -37,12 +75,66 @@
 
 void fork_abort (const char *msg);
 
-template<typename T, typename U> static inline T min (T a, U b) { return a < (T)b ? a : (T)b; }
-template<typename T, typename U> static inline T max (T a, U b) { return a > (T)b ? a : (T)b; }
-template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? a : v >(T)b ? b : v; }
+// 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>
+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
@@ -133,7 +225,11 @@
 template<typename T>
 inline void sfree (T *ptr, int n = 1) throw ()
 {
+#ifdef PREFER_MALLOC
+  free (ptr);
+#else
   g_slice_free1 (n * sizeof (T), (void *)ptr);
+#endif
 }
 
 // a STL-compatible allocator that uses g_slice
@@ -211,18 +307,18 @@
   uint32_t next ();
 
   // uniform distribution
-  uint32_t operator ()(uint32_t r_max)
+  uint32_t operator ()(uint32_t num)
   {
-    return is_constant (r_max)
-             ? this->next () % r_max
-             : get_range (r_max);
+    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 + (*this) (max (r_max - r_min + 1, 1))
+    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);
   }
 
@@ -311,6 +407,10 @@
   }
 };
 
+// Mostly the same as std::vector, but insert/erase can reorder
+// the elements, making insret/remove O(1) instead of O(n).
+//
+// NOTE: only some forms of erase/insert are available
 template<class T>
 struct unordered_vector : std::vector<T, slice_allocator<T> >
 {
@@ -330,12 +430,37 @@
   }
 };
 
+// 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
 template<class T, int T::* index>
 struct object_vector : std::vector<T *, slice_allocator<T *> >
 {
+  typedef typename object_vector::iterator iterator;
+
+  bool contains (const T *obj) const
+  {
+    return obj->*index;
+  }
+
+  iterator find (const T *obj)
+  {
+    return obj->*index
+      ? this->begin () + obj->*index - 1
+      : this->end ();
+  }
+
   void insert (T *obj)
   {
-    assert (!(obj->*index));
     push_back (obj);
     obj->*index = this->size ();
   }
@@ -347,8 +472,7 @@
 
   void erase (T *obj)
   {
-    assert (obj->*index);
-    int pos = obj->*index;
+    unsigned int pos = obj->*index;
     obj->*index = 0;
 
     if (pos < this->size ())
@@ -383,5 +507,8 @@
 
 int similar_direction (int a, int b);
 
+// like printf, but returns a std::string
+const std::string format (const char *format, ...);
+
 #endif