pipecom on 3.9x verions of QB64

[a740g]

I can't say that I'm confirming the issue because I'm running my Windows version of QB64pe in Wine, but I will say it did work before but is currently not working in 3.9.1. Pretty sure it's something that would have changed with QB64pe itself, but I wouldn't know what. Would probably need Matt or Samuel to take a peek.

Would you be able to share the latest version of pipecom? Or better yet, share a working example.

BTW, I peeked at the C header in bplus's post, and it uses the C++ standard library string class without the std namespace.

We got rid of using namespace std from libqb.cpp in 3.9.0 and newer (and for good reasons). So, now you'll just need to add std:: before all C++ standard library stuff.

[DSMan195276]

The problem is these two lines in the code:

Code: (Select All)

While ReadFile(hStdOutPipeRead, _Offset(buf), 4096, _Offset(dwRead), 0) <> 0 And dwRead > 0
' ...
While ReadFile(hStdReadPipeError, _Offset(buf), 4096, _Offset(dwRead), 0) <> 0 And dwRead > 0

The issue is that `And` does not require the left side to be evaluated first, rather the compiler picks the order it wants to evaluate the operands in. In this case that creates a bug because the right side of the `And` depends on the result from the left side (since it assigns `dwRead`). In v3.9.0 there is a new MinGW version and it apparently decides to evaluate the `dwRead > 0` side first, resulting in the check always failing since `dwRead` starts as zero.

I'm not really sure if this is a QB64 bug or not, this is definitely something that could always happen in every QB64 version and pipecom was just getting lucky. That said this behavior probably wasn't intentional and mostly just comes from the C behavior - in C the bitwsie operators do not imply evaluation ordering like the logical operators do. A good thing to know is if in QB45 the bitwise operators did imply evaluation order and QB64 isn't doing that, or if this kind of thing could always happen. I suspect they probably did by accident since I doubt QB45 did much in the way of optimization.

[SpriggsySpriggs]

Interesting. Let me adjust those lines and see what happens.

[SMcNeill]

Code: (Select All)

COMMON SHARED winver%, utente$
COMMON SHARED ip4$

DIM ver AS STRING
ver = MID$(pipecom_lite("ver"), 2)

PRINT pipecom_lite("ver")
SLEEP



k$ = ""
FOR f = 1 TO LEN(ver)
    IF INSTR("1234567890.", MID$(ver, f, 1)) <> 0 THEN k$ = k$ + MID$(ver, f, 1)
NEXT f
IF INSTR(k$, "6.1.76") > 0 THEN
    winver = 7
ELSEIF INSTR(k$, "6.2.") > 0 OR INSTR(k$, "6.3.") > 0 THEN
    winver = 8
ELSEIF INSTR(k$, "10.") > 0 THEN
    winver = 10
END IF

IF winver = 10 THEN
    FOR f = INSTR(_DIR$(""), "User") TO LEN(_DIR$(""))
        IF MID$(_DIR$(""), f, 1) = "\" THEN EXIT FOR
    NEXT f
    utente$ = MID$(_DIR$(""), f + 1, INSTR(MID$(_DIR$(""), f + 1), "\") - 1)
ELSEIF winver = 7 THEN
    FOR f = INSTR(_DIR$(""), "User") TO LEN(_DIR$(""))
        IF MID$(_DIR$(""), f, 1) = "\" THEN EXIT FOR
    NEXT f
    utente$ = MID$(_DIR$(""), f + 1, INSTR(MID$(_DIR$(""), f + 1), "\") - 1)
END IF


END



'-----------------------------------------------------------------------------------------------------------------------------
'6.0.6000  Windows Vista
'6.0.6001  Windows Vista with Service Pack 1 'or Windows Server 2008
'6.1.7600  Windows 7 'or Windows Server 2008 R2
'6.1.7601  Windows 7 with Service Pack 1 'or Windows Server 2008 R2 with Service Pack 1
'6.2.9200  Windows 8 'or Windows Server 2012
'6.3.9200  Windows 8.1 'or Windows Server 2012 R2
'6.3.9600  Windows 8.1 with Update 1
'10.0.10240 Windows 10 Version 1507
'10.0.10586 Windows 10 Version 1511 (November Update)
'10.0.14393 Windows 10 Version 1607 (Anniversary Update) 'or Windows Server 2016
'10.0.15063 Windows 10 Version 1703 (Creators Update)
'10.0.16299 Windows 10 Version 1709 (Fall Creators Update)
'10.0.17134 Windows 10 Version 1803 (April 2018 Update)
'10.0.17763 Windows 10 Version 1809 (October 2018 Update) 'or Windows Server 2019
'10.0.18362 Windows 10 Version 1903 (May 2019 Update)
'10.0.18363 Windows 10 Version 1909 (November 2019 Update)
'10.0.19041 Windows 10 Version 2004 (May 2020 Update)
'Note that there is normally no need to specify the build numbers (i.e., you may simply use "6.2" for Windows 8).
'-----------------------------------------------------------------------------------------------------------------------------




$IF PIPECOM = UNDEFINED THEN
    $LET PIPECOM = TRUE
    FUNCTION pipecom& (cmd AS STRING, stdout AS STRING, stderr AS STRING)
        stdout = "": stderr = ""
        $IF WIN THEN
            TYPE SECURITY_ATTRIBUTES
                AS _UNSIGNED LONG nLength
                $IF 64BIT THEN
                    AS STRING * 4 padding
                $END IF 
                AS _OFFSET lpSecurityDescriptor
                AS LONG bInheritHandle
                $IF 64BIT THEN
                    AS STRING * 4 padding2
                $END IF 
            END TYPE

            TYPE STARTUPINFO
                AS LONG cb
                $IF 64BIT THEN
                    AS STRING * 4 padding
                $END IF 
                AS _OFFSET lpReserved, lpDesktop, lpTitle
                AS _UNSIGNED LONG dwX, dwY, dwXSize, dwYSize, dwXCountChars, dwYCountChars, dwFillAttribute, dwFlags
                AS _UNSIGNED INTEGER wShowWindow, cbReserved2
                $IF 64BIT THEN
                    AS STRING * 4 padding2
                $END IF 
                AS _OFFSET lpReserved2, hStdInput, hStdOutput, hStdError
            END TYPE

            TYPE PROCESS_INFORMATION
                AS _OFFSET hProcess, hThread
                AS _UNSIGNED LONG dwProcessId
                $IF 64BIT THEN
                    AS STRING * 4 padding
                $END IF 
            END TYPE

            CONST STARTF_USESTDHANDLES = &H00000100
            CONST CREATE_NO_WINDOW = &H8000000

            CONST INFINITE = 4294967295
            CONST WAIT_FAILED = &HFFFFFFFF

            DECLARE CUSTOMTYPE LIBRARY
                FUNCTION CreatePipe& (BYVAL hReadPipe AS _OFFSET, BYVAL hWritePipe AS _OFFSET, BYVAL lpPipeAttributes AS _OFFSET, BYVAL nSize AS _UNSIGNED LONG)
                FUNCTION CreateProcess& (BYVAL lpApplicationName AS _OFFSET, BYVAL lpCommandLine AS _OFFSET, BYVAL lpProcessAttributes AS _OFFSET, BYVAL lpThreadAttributes AS _OFFSET, BYVAL bInheritHandles AS LONG, BYVAL dwCreationFlags AS _UNSIGNED LONG, BYVAL lpEnvironment AS _OFFSET, BYVAL lpCurrentDirectory AS _OFFSET, BYVAL lpStartupInfo AS _OFFSET, BYVAL lpProcessInformation AS _OFFSET)
                FUNCTION GetExitCodeProcess& (BYVAL hProcess AS _OFFSET, BYVAL lpExitCode AS _OFFSET)
                SUB HandleClose ALIAS "CloseHandle" (BYVAL hObject AS _OFFSET)
                FUNCTION ReadFile& (BYVAL hFile AS _OFFSET, BYVAL lpBuffer AS _OFFSET, BYVAL nNumberOfBytesToRead AS _UNSIGNED LONG, BYVAL lpNumberOfBytesRead AS _OFFSET, BYVAL lpOverlapped AS _OFFSET)
                FUNCTION WaitForSingleObject~& (BYVAL hHandle AS _OFFSET, BYVAL dwMilliseconds AS _UNSIGNED LONG)
            END DECLARE

            DIM AS LONG ok: ok = 1
            DIM AS _OFFSET hStdOutPipeRead, hStdOutPipeWrite, hStdReadPipeError, hStdOutPipeError
            DIM AS SECURITY_ATTRIBUTES sa: sa.nLength = LEN(sa): sa.lpSecurityDescriptor = 0: sa.bInheritHandle = 1

            IF CreatePipe(_OFFSET(hStdOutPipeRead), _OFFSET(hStdOutPipeWrite), _OFFSET(sa), 0) = 0 THEN
                pipecom = -1
                EXIT FUNCTION
            END IF

            IF CreatePipe(_OFFSET(hStdReadPipeError), _OFFSET(hStdOutPipeError), _OFFSET(sa), 0) = 0 THEN
                pipecom = -1
                EXIT FUNCTION
            END IF

            DIM si AS STARTUPINFO
            si.cb = LEN(si)
            si.dwFlags = STARTF_USESTDHANDLES
            si.hStdError = hStdOutPipeError
            si.hStdOutput = hStdOutPipeWrite
            si.hStdInput = 0
            DIM AS PROCESS_INFORMATION procinfo
            DIM AS _OFFSET lpApplicationName
            DIM AS STRING lpCommandLine: lpCommandLine = "cmd /c " + cmd + CHR$(0)
            DIM AS _OFFSET lpProcessAttributes, lpThreadAttributes
            DIM AS LONG bInheritHandles: bInheritHandles = 1
            DIM AS _UNSIGNED LONG dwCreationFlags: dwCreationFlags = CREATE_NO_WINDOW
            DIM AS _OFFSET lpEnvironment, lpCurrentDirectory
            ok = CreateProcess(lpApplicationName, _OFFSET(lpCommandLine), lpProcessAttributes, lpThreadAttributes, bInheritHandles, dwCreationFlags, lpEnvironment, lpCurrentDirectory, _OFFSET(si), _OFFSET(procinfo))

            IF ok = 0 THEN
                pipecom = -1
                EXIT FUNCTION
            END IF

            HandleClose hStdOutPipeWrite
            HandleClose hStdOutPipeError

            DIM AS STRING buf: buf = SPACE$(4096 + 1)
            DIM AS _UNSIGNED LONG dwRead
            WHILE 1
                'While ReadFile(hStdOutPipeRead, _Offset(buf), 4096, _Offset(dwRead), 0) <> 0 And dwRead > 0
                x = ReadFile(hStdOutPipeRead, _OFFSET(buf), 4096, _OFFSET(dwRead), 0)
                IF x <> 0 AND dwRead > 0 THEN
                    buf = MID$(buf, 1, dwRead)
                    GOSUB RemoveChr13
                    stdout = stdout + buf
                    buf = SPACE$(4096 + 1)
                ELSE
                    EXIT WHILE
                END IF
            WEND

            WHILE 1
                x = ReadFile(hStdReadPipeError, _OFFSET(buf), 4096, _OFFSET(dwRead), 0)
                IF x <> 0 AND dwRead > 0 THEN
                    buf = MID$(buf, 1, dwRead)
                    GOSUB RemoveChr13
                    stderr = stderr + buf
                    buf = SPACE$(4096 + 1)
                ELSE
                    EXIT FUNCTION
                END IF
            WEND

            DIM AS LONG exit_code, ex_stat
            IF WaitForSingleObject(procinfo.hProcess, INFINITE) <> WAIT_FAILED THEN
                IF GetExitCodeProcess(procinfo.hProcess, _OFFSET(exit_code)) THEN
                    ex_stat = 1
                END IF
            END IF

            HandleClose hStdOutPipeRead
            HandleClose hStdReadPipeError
            IF ex_stat = 1 THEN
                pipecom = exit_code
            ELSE
                pipecom = -1
            END IF

            EXIT FUNCTION

            RemoveChr13:
            DIM AS LONG j
            j = INSTR(buf, CHR$(13))
            DO WHILE j
                buf = LEFT$(buf, j - 1) + MID$(buf, j + 1)
                j = INSTR(buf, CHR$(13))
            LOOP
            RETURN
        $ELSE
                Declare CustomType Library
                Function popen%& (cmd As String, readtype As String)
                Function feof& (ByVal stream As _Offset)
                Function fgets$ (str As String, Byval n As Long, Byval stream As _Offset)
                Function pclose& (ByVal stream As _Offset)
                End Declare

                Declare Library
                Function WEXITSTATUS& (ByVal stat_val As Long)
                End Declare

                Dim As _Offset stream

                Dim buffer As String * 4096
                If _FileExists("pipestderr") Then
                Kill "pipestderr"
                End If
                stream = popen(cmd + " 2>pipestderr", "r")
                If stream Then
                While feof(stream) = 0
                If fgets(buffer, 4096, stream) <> "" And feof(stream) = 0 Then
                stdout = stdout + Mid$(buffer, 1, InStr(buffer, Chr$(0)) - 1)
                End If
                Wend
                Dim As Long status, exit_code
                status = pclose(stream)
                exit_code = WEXITSTATUS(status)
                If _FileExists("pipestderr") Then
                Dim As Integer errfile
                errfile=FREEFILE
                Open "pipestderr" For Binary As #errfile
                If LOF(errfile) > 0 Then
                stderr = Space$(LOF(errfile))
                Get #errfile, , stderr
                End If
                Close #errfile
                Kill "pipestderr"
                End If
                pipecom = exit_code
                Else
                pipecom = -1
                End If
        $END IF 
    END FUNCTION

    FUNCTION pipecom_lite$ (cmd AS STRING)
        DIM AS LONG a
        DIM AS STRING stdout, stderr
        a = pipecom(cmd, stdout, stderr)
        IF stderr <> "" THEN
            pipecom_lite = stderr
        ELSE
            pipecom_lite = stdout
        END IF
    END FUNCTION
$END IF 

Fixed version for you. 

[SpriggsySpriggs]

That was exactly the issue. I changed the lines to:

Code: (Select All)

    While ReadFile(hStdOutPipeRead, _Offset(buf), 4096, _Offset(dwRead), 0) <> 0
        If dwRead > 0 Then
            buf = Mid$(buf, 1, dwRead)
            GoSub RemoveChr13
            stdout = stdout + buf
            buf = Space$(4096 + 1)
        End If
    Wend
 
    While ReadFile(hStdReadPipeError, _Offset(buf), 4096, _Offset(dwRead), 0) <> 0
        If dwRead > 0 Then
            buf = Mid$(buf, 1, dwRead)
            GoSub RemoveChr13
            stderr = stderr + buf
            buf = Space$(4096 + 1)
        End If
    Wend

Very crazy that mingw's new version would adjust things so much. I wonder how many other programs might get screwed.

[SMcNeill]

Fix I used was here, to make certain that things get evaluated in order:

Code: (Select All)

            WHILE 1
                'While ReadFile(hStdOutPipeRead, _Offset(buf), 4096, _Offset(dwRead), 0) <> 0 And dwRead > 0
                x = ReadFile(hStdOutPipeRead, _OFFSET(buf), 4096, _OFFSET(dwRead), 0)
                IF x <> 0 AND dwRead > 0 THEN
                    buf = MID$(buf, 1, dwRead)
                    GOSUB RemoveChr13
                    stdout = stdout + buf
                    buf = SPACE$(4096 + 1)
                ELSE
                    EXIT WHILE
                END IF
            WEND

            WHILE 1
                x = ReadFile(hStdReadPipeError, _OFFSET(buf), 4096, _OFFSET(dwRead), 0)
                IF x <> 0 AND dwRead > 0 THEN
                    buf = MID$(buf, 1, dwRead)
                    GOSUB RemoveChr13
                    stderr = stderr + buf
                    buf = SPACE$(4096 + 1)
                ELSE
                    EXIT FUNCTION
                END IF
            WEND

[SpriggsySpriggs]

Yeah, I like my fix better.

[krovit]

Thank you, very fast! 
Now everything works again

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