--- deliantra/server/include/util.h 2008/12/04 03:48:19 1.78 +++ deliantra/server/include/util.h 2009/11/11 03:52:44 1.96 @@ -3,18 +3,19 @@ * * 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. + * Deliantra is free software: you can redistribute it and/or modify it under + * the terms of the Affero 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 . + * You should have received a copy of the Affero GNU General Public License + * and the GNU General Public License along with this program. If not, see + * . * * The authors can be reached via e-mail to */ @@ -22,30 +23,12 @@ #ifndef UTIL_H__ #define UTIL_H__ +#include + #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 #include @@ -74,7 +57,7 @@ // 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 +// very ugly macro that basically 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) @@ -98,22 +81,45 @@ template static inline T max (T a, U b) { return (U)a > b ? (U)a : b; } template static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; } -template static inline void min_it (T &v, T m) { v = min (v, m); } -template static inline void max_it (T &v, T m) { v = max (v, m); } -template static inline void clamp_it (T &v, T a, T b) { v = clamp (v, a, b); } +template static inline void min_it (T &v, U m) { v = min (v, (T)m); } +template static inline void max_it (T &v, U m) { v = max (v, (T)m); } +template static inline void clamp_it (T &v, U a, V b) { v = clamp (v, (T)a, (T)b); } template static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; } template static inline T min (T a, U b, V c) { return min (a, min (b, c)); } template static inline T max (T a, U b, V c) { return max (a, max (b, c)); } +// sign returns -1 or +1 +template +static inline T sign (T v) { return v < 0 ? -1 : +1; } +// relies on 2c representation +template<> +inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); } + +// sign0 returns -1, 0 or +1 +template +static inline T sign0 (T v) { return v ? sign (v) : 0; } + +// div* only work correctly for div > 0 // div, with correct rounding (< 0.5 downwards, >=0.5 upwards) -template static inline T div (T val, T div) { return (val + div / 2) / div; } +template static inline T div (T val, T div) +{ + return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; +} // div, round-up -template static inline T div_ru (T val, T div) { return (val + div - 1) / div; } +template static inline T div_ru (T val, T div) +{ + return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; +} // div, round-down -template static inline T div_rd (T val, T div) { return (val ) / div; } +template static inline T div_rd (T val, T div) +{ + return expect_false (val < 0) ? - ((-val + (div - 1) ) / div) : (val ) / div; +} +// lerp* only work correctly for min_in < max_in +// Linear intERPolate, scales val from min_in..max_in to min_out..max_out template static inline T lerp (T val, T min_in, T max_in, T min_out, T max_out) @@ -182,7 +188,7 @@ return b - d; } -// this is much faster than crossfires original algorithm +// this is much faster than crossfire's original algorithm // on modern cpus inline int isqrt (int n) @@ -190,6 +196,20 @@ return (int)sqrtf ((float)n); } +// this is kind of like the ^^ operator, if it would exist, without sequence point. +// more handy than it looks like, due to the implicit !! done on its arguments +inline bool +logical_xor (bool a, bool b) +{ + return a != b; +} + +inline bool +logical_implies (bool a, bool b) +{ + return a <= b; +} + // 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. @@ -222,6 +242,20 @@ return ((d - 1) & 7) + 1; } +// avoid ctz name because netbsd or freebsd spams it's namespace with it +#if GCC_VERSION(3,4) +static inline int least_significant_bit (uint32_t x) +{ + return __builtin_ctz (x); +} +#else +int least_significant_bit (uint32_t x); +#endif + +#define for_all_bits_sparse_32(mask, idxvar) \ + for (uint32_t idxvar, mask_ = mask; \ + mask_ && ((idxvar = least_significant_bit (mask_)), mask_ &= ~(1 << idxvar), 1);) + extern ssize_t slice_alloc; // statistics void *salloc_ (int n) throw (std::bad_alloc); @@ -380,7 +414,6 @@ // 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) @@ -393,13 +426,47 @@ void seed (uint32_t seed); uint32_t next (); +}; +// Xorshift RNGs, George Marsaglia +// http://www.jstatsoft.org/v08/i14/paper +// this one is about 40% faster than the tausworthe one above (i.e. not much), +// despite the inlining, and has the issue of only creating 2**32-1 numbers. +// see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf +struct xorshift_random_generator +{ + uint32_t x, y; + + void operator =(const xorshift_random_generator &src) + { + x = src.x; + y = src.y; + } + + void seed (uint32_t seed) + { + x = seed; + y = seed * 69069U; + } + + uint32_t next () + { + uint32_t t = x ^ (x << 10); + x = y; + y = y ^ (y >> 13) ^ t ^ (t >> 10); + return y; + } +}; + +template +struct random_number_generator : generator +{ // 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 !is_constant (num) ? get_range (num) // non-constant + : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two + : this->next () & (num - 1); // constant, power-of-two } // return a number within (min .. max) @@ -420,7 +487,7 @@ int get_range (int r_min, int r_max); }; -typedef tausworthe_random_generator rand_gen; +typedef random_number_generator rand_gen; extern rand_gen rndm, rmg_rndm; @@ -495,29 +562,45 @@ typedef refptr client_ptr; typedef refptr player_ptr; +#define STRHSH_NULL 2166136261 + +static inline uint32_t +strhsh (const char *s) +{ + // use FNV-1a hash (http://isthe.com/chongo/tech/comp/fnv/) + // it is about twice as fast as the one-at-a-time one, + // with good distribution. + // FNV-1a is faster on many cpus because the multiplication + // runs concurrently with the looping logic. + uint32_t hash = STRHSH_NULL; + + while (*s) + hash = (hash ^ *s++) * 16777619; + + return hash; +} + +static inline uint32_t +memhsh (const char *s, size_t len) +{ + uint32_t hash = STRHSH_NULL; + + while (len--) + hash = (hash ^ *s++) * 16777619; + + return hash; +} + 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 strhsh (s); + } - return hash; + std::size_t operator ()(const shstr &s) const + { + return strhsh (s); } }; @@ -620,13 +703,14 @@ }; // basically does what strncpy should do, but appends "..." to strings exceeding length -void assign (char *dst, const char *src, int maxlen); +// returns the number of bytes actually used (including \0) +int assign (char *dst, const char *src, int maxsize); // type-safe version of assign template -inline void assign (char (&dst)[N], const char *src) +inline int assign (char (&dst)[N], const char *src) { - assign ((char *)&dst, src, N); + return assign ((char *)&dst, src, N); } typedef double tstamp; @@ -636,8 +720,12 @@ int similar_direction (int a, int b); -// like sprintf, but returns a "static" buffer -const char *format (const char *format, ...); +// like v?sprintf, but returns a "static" buffer +char *vformat (const char *format, va_list ap); +char *format (const char *format, ...) attribute ((format (printf, 1, 2))); + +// safety-check player input which will become object->msg +bool msg_is_safe (const char *msg); ///////////////////////////////////////////////////////////////////////////// // threads, very very thin wrappers around pthreads