#include "stdafx.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/utime.h>

#include <boost/filesystem.hpp>

#include <windows.h>

int main(int argc, char *argv[])
{    
    time_t modtime = time(NULL) - 24 * 60 * 60;
    FILE *f;

    if (argc < 3) {
        printf("please provide 2 different test files paths on a network driver, i.e. '<prog> Y:\\afile.txt Y:\\bfile.txt'\n");
        return 1;
    }
    char *boostfile = argv[1];
    char *utimefile = argv[2];
    //
    // demonstrate the problem first
    //
    printf("\ntest boost::last_write_time(f,t) to modifty last write time on %s\n", boostfile);

    f = fopen(boostfile,"wb"); fwrite("X",1,1,f); fclose(f);
    printf("%lld - original last write time\n", boost::filesystem::last_write_time(boostfile));
    
    f = fopen(boostfile,"r+b"); fwrite("X",1,1,f); fclose(f);
    boost::filesystem::last_write_time(boostfile, modtime);
    printf("%lld - last write time after calling boost::last_write_time to modify it\n", boost::filesystem::last_write_time(boostfile));

    f = fopen(boostfile,"r"); fclose(f);
    printf("%lld [TEST:%s] last write opening for read - Expected %lld\n", 
        boost::filesystem::last_write_time(boostfile), 
        boost::filesystem::last_write_time(boostfile) == modtime ? "PASS" : "FAIL",
        modtime);

    //
    // demonstrate the problem expected behavior
    //
    printf("\ntest utime() on %s\n", utimefile);    

    f = fopen(utimefile,"wb"); fwrite("X",1,1,f); fclose(f);
    printf("%lld - original last write time\n", boost::filesystem::last_write_time(utimefile));
    
    f = fopen(utimefile,"r+b"); fwrite("X",1,1,f); fclose(f);
    
    struct utimbuf u;
    u.actime = 0;
    u.modtime = modtime;    
    utime(utimefile, &u);

    printf("%lld - last write time after calling utime() to modify it\n", boost::filesystem::last_write_time(utimefile));

    f = fopen(utimefile,"r"); fclose(f); 
    printf("%lld [TEST:%s] last write opening for read - Expected %lld\n", 
        boost::filesystem::last_write_time(utimefile), 
        boost::filesystem::last_write_time(utimefile) == modtime ? "PASS" : "FAIL",
        modtime);
    
    //
    // demonstrate perhaps how to fix it using FILE_GENERIC_WRITE rather than just FILE_WRITE_ATTRIBUTES
    //
    printf("\nshow 'better' windows API usage to modifty last write time on %s\n", boostfile);

    f = fopen(boostfile,"wb"); fwrite("X",1,1,f); fclose(f);
    printf("%lld original last write time\n", boost::filesystem::last_write_time(boostfile));
    
    f = fopen(boostfile,"r+b"); fwrite("X",1,1,f); fclose(f);

    // using boost's technique as see in http://svn.boost.org/svn/boost/trunk/libs/filesystem/v3/src/operations.cpp (in last_write_time -- variant that modifies time) 
    //                                or http://svn.boost.org/svn/boost/trunk/libs/filesystem/v2/src/v2_operations.cpp (in set_file_write_time )
    {
        HANDLE h = CreateFileA(boostfile, FILE_GENERIC_WRITE,
            FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE, 0,
            OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, 0);

        FILETIME lwt;
        __int64 temp = modtime;
        temp *= 10000000;
        temp += 116444736000000000LL;
        
        lwt.dwLowDateTime = static_cast<DWORD>(temp);
        lwt.dwHighDateTime = static_cast<DWORD>(temp >> 32);
        
        SetFileTime(h, 0, 0, &lwt);
    }    
    printf("%lld - last write time after calling native SetFileTime() with a handle with FILE_GENERIC_ACCESS\n", boost::filesystem::last_write_time(boostfile));

    f = fopen(boostfile,"r"); fclose(f); 
    printf("%lld [TEST:%s] last write opening for read - Expected %lld\n", 
        boost::filesystem::last_write_time(boostfile), 
        boost::filesystem::last_write_time(boostfile) == modtime ? "PASS" : "FAIL",
        modtime);

    return 0;
}