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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 attempt to read from the
** locked file to ensure it is locked. After it has been unlocked, it
** will then read again to check that Unlock worked.
**
**
**============================================================*/
#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;
char DataBuffer[BUF_SIZE];
DWORD BytesRead;
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;
}
/* Check to ensure the parent lock is respected */
if(ReadFile(TheFile, DataBuffer, 10, &BytesRead, NULL) != 0)
{
Trace("ERROR: ReadFile returned success when it should "
"have failed. Attempted to read the first 10 bytes "
"of a file which was locked by the parent process.\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 unlock the file */
SignalAndBusyWait(WaitFile);
if(ReadFile(TheFile, DataBuffer, 10, &BytesRead, NULL) == 0)
{
Trace("ERROR: ReadFile was unable to read from the file after it "
"had been unlocked. Attempted to read 10 bytes and ReadFile "
"returned 0. GetLastError() returned %d.\n",GetLastError());
result = 1;
}
PAL_TerminateEx(result);
return result;
}
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