ReactOS 0.4.15-dev-7958-gcd0bb1a
Macros | Functions | Variables
random.c File Reference
#include <rtl.h>
#include <debug.h>
Include dependency graph for random.c:

Go to the source code of this file.

Macros

#define NDEBUG
 
#define LCG_A   0x7fffffed
 
#define LCG_C   0x7fffffc3
 
#define LCG_M   MAXLONG
 

Functions

ULONG NTAPI RtlRandom (IN OUT PULONG Seed)
 
ULONG NTAPI RtlRandomEx (IN OUT PULONG Seed)
 
ULONG NTAPI RtlUniform (IN PULONG Seed)
 

Variables

static ULONG RtlpRandomConstantVector [128]
 
static ULONG RtlpRandomExConstantVector [128]
 
static ULONG RtlpRandomExAuxVarY = 0x7775fb16
 

Macro Definition Documentation

◆ LCG_A

#define LCG_A   0x7fffffed

Definition at line 91 of file random.c.

◆ LCG_C

#define LCG_C   0x7fffffc3

Definition at line 92 of file random.c.

◆ LCG_M

#define LCG_M   MAXLONG

Definition at line 93 of file random.c.

◆ NDEBUG

#define NDEBUG

Definition at line 14 of file random.c.

Function Documentation

◆ RtlRandom()

ULONG NTAPI RtlRandom ( IN OUT PULONG  Seed)

Definition at line 113 of file random.c.

114{
115 ULONG Rand;
116 int Pos;
117 ULONG Result;
118
119 PAGED_CODE_RTL();
120
121 Rand = (*Seed * LCG_A + LCG_C) % LCG_M;
122 *Seed = (Rand * LCG_A + LCG_C) % LCG_M;
123 Pos = *Seed & (sizeof(RtlpRandomConstantVector) / sizeof(RtlpRandomConstantVector[0]) - 1);
124 Result = RtlpRandomConstantVector[Pos];
125 RtlpRandomConstantVector[Pos] = Rand;
126
127 return Result;
128}
Pos
ush Pos
Definition: deflate.h:92
PAGED_CODE_RTL
#define PAGED_CODE_RTL()
Definition: rtlp.h:16
LCG_A
#define LCG_A
Definition: random.c:91
RtlpRandomConstantVector
static ULONG RtlpRandomConstantVector[128]
Definition: random.c:17
LCG_C
#define LCG_C
Definition: random.c:92
LCG_M
#define LCG_M
Definition: random.c:93
ULONG
uint32_t ULONG
Definition: typedefs.h:59
Result
_At_(*)(_In_ PWSK_CLIENT Client, _In_opt_ PUNICODE_STRING NodeName, _In_opt_ PUNICODE_STRING ServiceName, _In_opt_ ULONG NameSpace, _In_opt_ GUID *Provider, _In_opt_ PADDRINFOEXW Hints, _Outptr_ PADDRINFOEXW *Result, _In_opt_ PEPROCESS OwningProcess, _In_opt_ PETHREAD OwningThread, _Inout_ PIRP Irp Result)(Mem)) NTSTATUS(WSKAPI *PFN_WSK_GET_ADDRESS_INFO
Definition: wsk.h:409

◆ RtlRandomEx()

ULONG NTAPI RtlRandomEx ( IN OUT PULONG  Seed)

Definition at line 150 of file random.c.

152{
153 ULONG Rand;
154 int Pos;
155
156 PAGED_CODE_RTL();
157
158 Pos = RtlpRandomExAuxVarY & (sizeof(RtlpRandomExConstantVector) / sizeof(RtlpRandomExConstantVector[0]) - 1);
159 RtlpRandomExAuxVarY = RtlpRandomExConstantVector[Pos];
160 Rand = (*Seed * LCG_A + LCG_C) % LCG_M;
161 RtlpRandomExConstantVector[Pos] = Rand;
162 *Seed = Rand;
163
164 return Rand;
165}
RtlpRandomExConstantVector
static ULONG RtlpRandomExConstantVector[128]
Definition: random.c:53
RtlpRandomExAuxVarY
static ULONG RtlpRandomExAuxVarY
Definition: random.c:89

◆ RtlUniform()

ULONG NTAPI RtlUniform ( IN PULONG  Seed)

Definition at line 195 of file random.c.

196{
197 ULONG Result;
198
199 /* Generate the random number */
200 Result = (*Seed * LCG_A + LCG_C) % LCG_M;
201
202 /* Return it */
203 *Seed = Result;
204 return Result;
205}

Variable Documentation

◆ RtlpRandomConstantVector

ULONG RtlpRandomConstantVector[128]
static

Definition at line 17 of file random.c.

Referenced by RtlRandom().

◆ RtlpRandomExAuxVarY

ULONG RtlpRandomExAuxVarY = 0x7775fb16
static

Definition at line 89 of file random.c.

Referenced by RtlRandomEx().

◆ RtlpRandomExConstantVector

ULONG RtlpRandomExConstantVector[128]
static

Definition at line 53 of file random.c.

Referenced by RtlRandomEx().