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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: helper.c
**
** Purpose: A child process which will lock a portion of the file,
** then try to unlock a portion of the file which was locked by the parent.
**
**
**============================================================*/
#include <palsuite.h>
#include "../UnlockFile.h"
#define FILENAME "testfile.txt"
#define WAITFILENAME "waitfile"
#define BUF_SIZE 128
int __cdecl main(int argc, char *argv[])
{
HANDLE TheFile, WaitFile;
int result = 0;
if(0 != (PAL_Initialize(argc, argv)))
{
return FAIL;
}
/* Open the same file that the parent has opened and locked */
TheFile = CreateFile(FILENAME,
GENERIC_READ|GENERIC_WRITE,
FILE_SHARE_READ|FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (TheFile == INVALID_HANDLE_VALUE)
{
Trace("ERROR: Could not open file '%s' with CreateFile.\n",FILENAME);
result = 1;
}
/* Open up the WaitFile that we're using for IPC */
WaitFile = CreateFile(WAITFILENAME,
GENERIC_READ|GENERIC_WRITE,
FILE_SHARE_READ|FILE_SHARE_WRITE,
NULL,
OPEN_ALWAYS,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (WaitFile == INVALID_HANDLE_VALUE)
{
Trace("ERROR: Could not open file '%s' with CreateFile. "
"GetLastError() returned %d.\n",WAITFILENAME,GetLastError());
result = 1;
}
/* Lock a section of the file different from which was locked in the
parent proccess
*/
if(LockFile(TheFile, 10, 0, 10, 0) == 0)
{
Trace("ERROR: The LockFile call within the child failed to lock "
"the file. GetLastError() returned %d.\n",GetLastError());
result = 1;
}
/* Attempt to unlock the portion of the file which was locked within the
parent process.
*/
if(UnlockFile(TheFile, 0, 0, 10, 0) != 0)
{
Trace("ERROR: The UnlockFile call within the child succeeded in "
"calling UnlockFile on the portion of the file which was "
"locked by the parent.\n");
result = 1;
}
// Sleep for a bit to give the parent a chance to block before we do.
Sleep(1000);
/* Switch back to the parent, so it can check the child lock */
SignalAndBusyWait(WaitFile);
/* Finally, clean up the lock which was done within this proccess and
exit.
*/
if(UnlockFile(TheFile, 10, 0, 10, 0) == 0)
{
Trace("ERROR: The UnlockFile call within the child failed to unlock "
"the portion of the file which was locked by the child. "
"GetLastError() returned %d.\n", GetLastError());
result = 1;
}
PAL_TerminateEx(result);
return result;
}
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