Initial community commit

1 files changed, 226 insertions, 0 deletions

diff --git a/Src/Winamp/rand.cpp b/Src/Winamp/rand.cpp
new file mode 100644
index 00000000..8bdea897
--- /dev/null
+++ b/Src/Winamp/rand.cpp
@@ -0,0 +1,226 @@
+/** (c) Nullsoft, Inc.         C O N F I D E N T I A L
+ ** Filename: 
+ ** Project:
+ ** Description:
+ ** Author: Ben Allison benski@nullsoft.com
+ ** Created:
+ **/
+#include "main.h"
+#include "random.h"
+#include <wincrypt.h>
+/* Period parameters */
+#define N 624
+#define M 397
+#define MATRIX_A 0x9908b0dfUL   /* constant vector a */
+#define UPPER_MASK 0x80000000UL /* most significant w-r bits */
+#define LOWER_MASK 0x7fffffffUL /* least significant r bits */
+
+static unsigned long mt[N]; /* the array for the state vector  */
+static int mti = N + 1; /* mti==N+1 means mt[N] is not initialized */
+
+static CRITICAL_SECTION randCS;
+/* initializes mt[N] with a seed */
+void init_genrand(unsigned long s)
+{
+	mt[0] = s & 0xffffffffUL;
+	for (mti = 1; mti < N; mti++)
+	{
+		mt[mti] =
+		    (1812433253UL * (mt[mti - 1] ^ (mt[mti - 1] >> 30)) + mti);
+		mt[mti] &= 0xffffffffUL;
+	}
+}
+
+/* initialize by an array with array-length */
+/* init_key is the array for initializing keys */
+/* key_length is its length */
+/* slight change for C++, 2004/2/26 */
+void init_by_array(unsigned long init_key[], int key_length)
+{
+    int i, j, k;
+    init_genrand(19650218UL);
+    i=1; j=0;
+    k = (N>key_length ? N : key_length);
+    for (; k; k--) {
+        mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1664525UL))
+          + init_key[j] + j; /* non linear */
+        mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
+        i++; j++;
+        if (i>=N) { mt[0] = mt[N-1]; i=1; }
+        if (j>=key_length) j=0;
+    }
+    for (k=N-1; k; k--) {
+        mt[i] = (mt[i] ^ ((mt[i-1] ^ (mt[i-1] >> 30)) * 1566083941UL))
+          - i; /* non linear */
+        mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
+        i++;
+        if (i>=N) { mt[0] = mt[N-1]; i=1; }
+    }
+
+    mt[0] = 0x80000000UL; /* MSB is 1; assuring non-zero initial array */ 
+}
+
+static const unsigned long mag01[2] = {0x0UL, MATRIX_A};
+/* mag01[x] = x * MATRIX_A  for x=0,1 */
+
+/* generates a random number on [0,0xffffffff]-interval */
+unsigned long genrand_int32(void)
+{
+	EnterCriticalSection(&randCS);
+	unsigned long y;
+
+	if (mti >= N)
+	{ /* generate N words at one time */
+		int kk;
+		// benski> CUT - because we call init_genrand() as the first thing in WinMain
+		//if (mti == N+1)   /* if init_genrand() has not been called, */
+		// benski> CUT init_genrand(5489UL); /* a default initial seed is used */
+
+		for (kk = 0;kk < N - M;kk++)
+		{
+			y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
+			mt[kk] = mt[kk + M] ^ (y >> 1) ^ mag01[y & 0x1UL];
+		}
+		for (;kk < N - 1;kk++)
+		{
+			y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
+			mt[kk] = mt[kk + (M - N)] ^ (y >> 1) ^ mag01[y & 0x1UL];
+		}
+		y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
+		mt[N - 1] = mt[M - 1] ^ (y >> 1) ^ mag01[y & 0x1UL];
+
+		mti = 0;
+	}
+
+	y = mt[mti++];
+
+	LeaveCriticalSection(&randCS);
+
+	/* Tempering */
+	y ^= (y >> 11);
+	y ^= (y << 7) & 0x9d2c5680UL;
+	y ^= (y << 15) & 0xefc60000UL;
+	y ^= (y >> 18);
+	
+	return y;
+}
+
+/* generates a random number on [0,0x7fffffff]-interval */
+long genrand_int31(void)
+{
+	return (long)(genrand_int32() >> 1);
+}
+
+static HCRYPTPROV GetKeySet()
+{
+	HCRYPTPROV   hCryptProv;
+	LPCSTR UserName = "WinampKeyContainer";  // name of the key container
+
+	if(CryptAcquireContextA(&hCryptProv, UserName, NULL, PROV_RSA_FULL, 0))
+	{
+		return hCryptProv;
+	} 
+	else if(CryptAcquireContextA(&hCryptProv, UserName, NULL, PROV_RSA_FULL, CRYPT_NEWKEYSET)) 
+	{
+		return hCryptProv;
+	}
+	else
+		return 0;
+}
+
+Random::Random()
+{
+	InitializeCriticalSectionAndSpinCount(&randCS, 1000);
+
+	HCRYPTPROV hCryptProv = GetKeySet();
+	if (hCryptProv)
+	{
+		unsigned long seed_data[8];
+		if (CryptGenRandom(hCryptProv, sizeof(seed_data), (PBYTE)seed_data)) 
+		{
+			init_by_array(seed_data, 8);
+		}
+		CryptReleaseContext(hCryptProv,0);
+	}
+	else
+	{
+		LARGE_INTEGER performance_counter;
+		QueryPerformanceCounter(&performance_counter);
+
+		unsigned long seed_data[4] = {(unsigned long)performance_counter.HighPart, (unsigned long)performance_counter.LowPart, (unsigned long)GetTickCount64(), (unsigned long)GetCurrentProcessId()};
+		init_by_array(seed_data, 4);
+	}
+}
+
+int warand()
+{
+	return genrand_int31();
+}
+
+float warandf()
+{
+	return genrand_int32()*(1.0f / 4294967295.0f);
+}
+
+
+RandomGenerator Random::GetFunction()
+{
+	return warand;
+}
+
+UnsignedRandomGenerator Random::GetUnsignedFunction()
+{
+	return genrand_int32;
+}
+
+int Random::GetNumber()
+{
+	return genrand_int32();
+}
+
+int Random::GetPositiveNumber()
+{
+	return genrand_int31();
+}
+
+/* generates a random number on [0,1]-real-interval */
+float Random::GetFloat()
+{
+	return genrand_int32()*(1.0f / 4294967295.0f);
+	/* divided by 2^32-1 */
+}
+
+/* generates a random number on [0,1)-real-interval */
+float Random::GetFloat_LessThanOne()
+{
+	return genrand_int32()*(1.0f / 4294967296.0f);
+	/* divided by 2^32 */
+}
+/* generates a random number on (0,1)-real-interval */
+float Random::GetFloat_LessThanOne_NotZero()
+{
+	return (((float)genrand_int32()) + 0.5f)*(1.0f / 4294967296.0f);
+} // (0-1)
+
+/* generates a random number on [0,1) with 53-bit resolution*/
+double Random::GetDouble()
+{
+	unsigned long a = genrand_int32() >> 5, b = genrand_int32() >> 6;
+	return (a*67108864.0 + b)*(1.0 / 9007199254740992.0);
+}
+
+#ifdef CBCLASS
+#undef CBCLASS
+#endif
+
+#define CBCLASS Random
+START_DISPATCH;
+CB(API_RANDOM_GETFUNCTION, GetFunction)
+CB(API_RANDOM_GETFUNCTION_UNSIGNED, GetUnsignedFunction)
+CB(API_RANDOM_GETNUMBER, GetNumber)
+CB(API_RANDOM_GETPOSITIVENUMBER, GetPositiveNumber)
+CB(API_RANDOM_GETFLOAT, GetFloat)
+CB(API_RANDOM_GETFLOAT2, GetFloat_LessThanOne)
+CB(API_RANDOM_GETFLOAT3, GetFloat_LessThanOne_NotZero)
+CB(API_RANDOM_GETDOUBLE, GetDouble)
+END_DISPATCH
\ No newline at end of file