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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
/*============================================================
**
** Source: criticalsectionfunctions/test1/initializecriticalsection.c
**
** Purpose: Test Semaphore operation using classic IPC problem:
** "Producer-Consumer Problem".
**
** Dependencies: CreateThread
** InitializeCriticalSection
** EnterCriticalSection
** LeaveCriticalSection
** DeleteCriticalSection
** WaitForSingleObject
** Sleep
**
**
**=========================================================*/
#include <palsuite.h>
#define PRODUCTION_TOTAL 26
#define _BUF_SIZE 10
DWORD dwThreadId; /* consumer thread identifier */
HANDLE hThread; /* handle to consumer thread */
CRITICAL_SECTION CriticalSectionM; /* Critical Section Object (used as mutex) */
typedef struct Buffer
{
short readIndex;
short writeIndex;
CHAR message[_BUF_SIZE];
} BufferStructure;
CHAR producerItems[PRODUCTION_TOTAL + 1];
CHAR consumerItems[PRODUCTION_TOTAL + 1];
/*
* Read next message from the Buffer into provided pointer.
* Returns: 0 on failure, 1 on success.
*/
int
readBuf(BufferStructure *Buffer, char *c)
{
if( Buffer -> writeIndex == Buffer -> readIndex )
{
return 0;
}
*c = Buffer -> message[Buffer -> readIndex++];
Buffer -> readIndex %= _BUF_SIZE;
return 1;
}
/*
* Write message generated by the producer to Buffer.
* Returns: 0 on failure, 1 on success.
*/
int
writeBuf(BufferStructure *Buffer, CHAR c)
{
if( ( ((Buffer -> writeIndex) + 1) % _BUF_SIZE) ==
(Buffer -> readIndex) )
{
return 0;
}
Buffer -> message[Buffer -> writeIndex++] = c;
Buffer -> writeIndex %= _BUF_SIZE;
return 1;
}
/*
* Sleep 500 milleseconds.
*/
VOID
consumerSleep(VOID)
{
Sleep(500);
}
/*
* Sleep between 10 milleseconds.
*/
VOID
producerSleep(VOID)
{
Sleep(10);
}
/*
* Produce a message and write the message to Buffer.
*/
VOID
producer(BufferStructure *Buffer)
{
int n = 0;
char c;
while (n < PRODUCTION_TOTAL)
{
c = 'A' + n ; /* Produce Item */
EnterCriticalSection(&CriticalSectionM);
if (writeBuf(Buffer, c))
{
printf("Producer produces %c.\n", c);
producerItems[n++] = c;
}
LeaveCriticalSection(&CriticalSectionM);
producerSleep();
}
return;
}
/*
* Read and "Consume" the messages in Buffer.
*/
DWORD
PALAPI
consumer( LPVOID lpParam )
{
int n = 0;
char c;
consumerSleep();
while (n < PRODUCTION_TOTAL)
{
EnterCriticalSection(&CriticalSectionM);
if (readBuf((BufferStructure*)lpParam, &c))
{
printf("\tConsumer consumes %c.\n", c);
consumerItems[n++] = c;
}
LeaveCriticalSection(&CriticalSectionM);
consumerSleep();
}
return 0;
}
int __cdecl main (int argc, char **argv)
{
BufferStructure Buffer, *pBuffer;
pBuffer = &Buffer;
if(0 != (PAL_Initialize(argc, argv)))
{
return FAIL;
}
/*
* Create mutual exclusion mechanisms
*/
InitializeCriticalSection ( &CriticalSectionM );
/*
* Initialize Buffer
*/
pBuffer->writeIndex = pBuffer->readIndex = 0;
/*
* Create Consumer
*/
hThread = CreateThread(
NULL,
0,
consumer,
&Buffer,
0,
&dwThreadId);
if ( NULL == hThread )
{
Fail ( "CreateThread() returned NULL. Failing test.\n"
"GetLastError returned %d\n", GetLastError());
}
/*
* Start producing
*/
producer(pBuffer);
/*
* Wait for consumer to complete
*/
WaitForSingleObject (hThread, INFINITE);
/*
* Compare items produced vs. items consumed
*/
if ( 0 != strncmp (producerItems, consumerItems, PRODUCTION_TOTAL) )
{
Fail("The producerItems string %s\n and the consumerItems string "
"%s\ndo not match. This could be a problem with the strncmp()"
" function\n FailingTest\nGetLastError() returned %d\n",
producerItems, consumerItems, GetLastError());
}
/*
* Clean up Critical Section object
*/
DeleteCriticalSection(&CriticalSectionM);
Trace("producerItems and consumerItems arrays match. All %d\nitems "
"were produced and consumed in order.\nTest passed.\n",
PRODUCTION_TOTAL);
PAL_Terminate();
return (PASS);
}
|
