X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=synfig-core%2Ftrunk%2Fsrc%2Fsynfig%2Fguid.cpp;h=e537ba661410cfbd2cfc567e768b4ca88c793c34;hb=9459638ad6797b8139f1e9f0715c96076dbf0890;hp=bf234752b59f38f1577e73fdbb280d73ddb71007;hpb=e8a065f2385c219c511b57dac52786120bfa097d;p=synfig.git

diff --git a/synfig-core/trunk/src/synfig/guid.cpp b/synfig-core/trunk/src/synfig/guid.cpp
index bf23475..e537ba6 100644
--- a/synfig-core/trunk/src/synfig/guid.cpp
+++ b/synfig-core/trunk/src/synfig/guid.cpp
@@ -2,10 +2,11 @@
 /*!	\file guid.cpp
 **	\brief Template File
 **
-**	$Id: guid.cpp,v 1.4 2005/01/13 06:48:39 darco Exp $
+**	$Id$
 **
 **	\legal
 **	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+**	Copyright (c) 2007, 2008 Chris Moore
 **
 **	This package is free software; you can redistribute it and/or
 **	modify it under the terms of the GNU General Public License as
@@ -22,9 +23,6 @@
 
 /* === H E A D E R S ======================================================= */
 
-#define HASH_MAP_H <ext/hash_map>
-#define SUBTRACT_RNG_H <ext/functional>
-
 #ifdef USING_PCH
 #	include "pch.h"
 #else
@@ -33,6 +31,7 @@
 #endif
 
 #include "guid.h"
+#include "quick_rng.h"
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
@@ -46,12 +45,7 @@
 
 #ifdef HASH_MAP_H
 #include HASH_MAP_H
-using namespace __gnu_cxx;
-#endif
-
-#ifdef SUBTRACT_RNG_H
-#include SUBTRACT_RNG_H
-using namespace __gnu_cxx;
+#include FUNCTIONAL_H
 #endif
 
 #ifdef _WIN32
@@ -76,50 +70,6 @@ using namespace synfig;
 
 /* === M E T H O D S ======================================================= */
 
-// A fast 32-bit linear congruential random number generator
-class quick_rng
-{
-	unsigned long next;
-public:
-	quick_rng(unsigned long seed=0):next(seed) { }
-
-	void set_seed(unsigned long x)
-	{
-		next=x;
-	}
-	
-	unsigned long i32()
-	{
-		static const unsigned long a(1664525);
-		static const unsigned long c(1013904223);
-		
-		return next=next*a+c;
-	}
-
-	unsigned long i16()
-	{
-		return i32()>>16;
-	}
-
-	float f()
-	{
-		static const float m(int(65535));
-		
-		return float(i16())/m;
-	}
-	
-	unsigned long operator()(const unsigned long& m)
-	{
-		if(m==65536)
-			return i16();
-		else
-		if(m<=65536)
-			return i16()%m;
-		else
-			return i32()%m;
-	}
-};
-
 #define GUID_RNG quick_rng
 //#define GUID_RNG subtractive_rng
 
@@ -134,7 +84,7 @@ static void (*get_rand_long_long)(uint64_t&)=_set_up_rand_long_long;
 static void _set_up_rand_long_long(uint64_t &x)
 {
 #ifdef _DEBUG
-	synfig::info("Starting up GUID system...");
+	// synfig::info("Starting up GUID system...");
 #endif
 	_a=GUID_RNG(time(0)+clock());
 	_b=GUID_RNG(clock());
@@ -146,10 +96,10 @@ static void _get_rand_long_long(uint64_t &x)
 {
 	//subtractive_rng _c(clock());
 	unsigned short* data(reinterpret_cast<unsigned short *>(&x));
-	data[0]=_a(65536);	
-	data[1]=_a(65536);	
-	data[2]=_a(65536);	
-	data[3]=_a(65536);	
+	data[0]=_a(65536);
+	data[1]=_a(65536);
+	data[2]=_a(65536);
+	data[3]=_a(65536);
 }
 
 #else
@@ -160,7 +110,7 @@ static void _get_rand_long_long(uint64_t &x)
 static void get_rand_long_long(uint64_t &x)
 {
 	_GUID* guid(reinterpret_cast<_GUID*>(&x));
-	CoCreateGuid(guid);	
+	CoCreateGuid(guid);
 }
 
 #else
@@ -172,7 +122,7 @@ static void (*get_rand_long_long)(uint64_t&)=_set_up_rand_long_long;
 static void _set_up_rand_long_long(uint64_t &x)
 {
 #ifdef _DEBUG
-	synfig::info("Starting up GUID system...");
+	// synfig::info("Starting up GUID system...");
 #endif
 	rand_fd=open("/dev/urandom",O_RDONLY);
 	get_rand_long_long=_get_rand_long_long;
@@ -195,23 +145,34 @@ synfig::GUID::make_unique()
 
 synfig::GUID
 synfig::GUID::hasher(const String& str)
-{	
+{
 #ifdef HASH_MAP_H
-	hash<const char*> string_hash_;
-	const unsigned int seed(
-		string_hash_(
-			str.c_str()
-		)
-	);
-#else
-	const unsigned int seed(0x3B642879);
-	for(int i=0;i<str.size();i++)
+	/* http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2003/n1456.html says:
+	 *
+	 *   "Some earlier hash table implementations gave char* special
+	 *    treatment: it specialized the default hash function to look
+	 *    at character array being pointed to, rather than the pointer
+	 *    itself. This proposal removes that special treatment."
+	 *
+	 * Unfortunately, the older implementation doesn't seem to want to
+	 * accept Strings, so we're left with this conditional compilation.
+	 */
+# ifdef FUNCTIONAL_HASH_ON_STRING
+	HASH_MAP_NAMESPACE::hash<String> string_hash_;
+	const unsigned int seed(string_hash_(str));
+# else  // FUNCTIONAL_HASH_ON_STRING
+	HASH_MAP_NAMESPACE::hash<const char*> string_hash_;
+	const unsigned int seed(string_hash_(str.c_str()));
+# endif  // FUNCTIONAL_HASH_ON_STRING
+#else  // HASH_MAP_H
+	unsigned int seed(0x3B642879);
+	for(unsigned int i=0;i<str.size();i++)
 	{
-		seed^=(seed*str[i])*i
-		seed=(seed>>(32-(i%24)))^(seed<<(i%24))
+		seed^=(seed*str[i])*i;
+		seed=(seed>>(32-(i%24)))^(seed<<(i%24));
 	}
-#endif
-	
+#endif  // HASH_MAP_H
+
 	GUID_RNG random(seed);
 	GUID ret(0);
 	ret.data.u_32.a=random(~(unsigned int)0);