/*
* tclWinPipe.c --
*
* This file implements the Windows-specific exec pipeline functions, the
* "pipe" channel driver, and the "pid" Tcl command.
*
* Copyright (c) 1996-1997 by Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution of
* this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* RCS: @(#) $Id: tclWinPipe.c,v 1.65.4.1 2010/01/31 23:51:37 nijtmans Exp $
*/
#include "tclWinInt.h"
#include <sys/stat.h>
/*
* The following variable is used to tell whether this module has been
* initialized.
*/
static int initialized = 0;
/*
* The pipeMutex locks around access to the initialized and procList
* variables, and it is used to protect background threads from being
* terminated while they are using APIs that hold locks.
*/
TCL_DECLARE_MUTEX(pipeMutex)
/*
* The following defines identify the various types of applications that run
* under windows. There is special case code for the various types.
*/
#define APPL_NONE 0
#define APPL_DOS 1
#define APPL_WIN3X 2
#define APPL_WIN32 3
/*
* The following constants and structures are used to encapsulate the state of
* various types of files used in a pipeline. This used to have a 1 && 2 that
* supported Win32s.
*/
#define WIN_FILE 3 /* Basic Win32 file. */
/*
* This structure encapsulates the common state associated with all file types
* used in a pipeline.
*/
typedef struct WinFile {
int type; /* One of the file types defined above. */
HANDLE handle; /* Open file handle. */
} WinFile;
/*
* This list is used to map from pids to process handles.
*/
typedef struct ProcInfo {
HANDLE hProcess;
DWORD dwProcessId;
struct ProcInfo *nextPtr;
} ProcInfo;
static ProcInfo *procList;
/*
* Bit masks used in the flags field of the PipeInfo structure below.
*/
#define PIPE_PENDING (1<<0) /* Message is pending in the queue. */
#define PIPE_ASYNC (1<<1) /* Channel is non-blocking. */
/*
* Bit masks used in the sharedFlags field of the PipeInfo structure below.
*/
#define PIPE_EOF (1<<2) /* Pipe has reached EOF. */
#define PIPE_EXTRABYTE (1<<3) /* The reader thread has consumed one byte. */
/*
* This structure describes per-instance data for a pipe based channel.
*/
typedef struct PipeInfo {
struct PipeInfo *nextPtr; /* Pointer to next registered pipe. */
Tcl_Channel channel; /* Pointer to channel structure. */
int validMask; /* OR'ed combination of TCL_READABLE,
* TCL_WRITABLE, or TCL_EXCEPTION: indicates
* which operations are valid on the file. */
int watchMask; /* OR'ed combination of TCL_READABLE,
* TCL_WRITABLE, or TCL_EXCEPTION: indicates
* which events should be reported. */
int flags; /* State flags, see above for a list. */
TclFile readFile; /* Output from pipe. */
TclFile writeFile; /* Input from pipe. */
TclFile errorFile; /* Error output from pipe. */
int numPids; /* Number of processes attached to pipe. */
Tcl_Pid *pidPtr; /* Pids of attached processes. */
Tcl_ThreadId threadId; /* Thread to which events should be reported.
* This value is used by the reader/writer
* threads. */
HANDLE writeThread; /* Handle to writer thread. */
HANDLE readThread; /* Handle to reader thread. */
HANDLE writable; /* Manual-reset event to signal when the
* writer thread has finished waiting for the
* current buffer to be written. */
HANDLE readable; /* Manual-reset event to signal when the
* reader thread has finished waiting for
* input. */
HANDLE startWriter; /* Auto-reset event used by the main thread to
* signal when the writer thread should
* attempt to write to the pipe. */
HANDLE stopWriter; /* Manual-reset event used to alert the reader
* thread to fall-out and exit */
HANDLE startReader; /* Auto-reset event used by the main thread to
* signal when the reader thread should
* attempt to read from the pipe. */
HANDLE stopReader; /* Manual-reset event used to alert the reader
* thread to fall-out and exit */
DWORD writeError; /* An error caused by the last background
* write. Set to 0 if no error has been
* detected. This word is shared with the
* writer thread so access must be
* synchronized with the writable object.
*/
char *writeBuf; /* Current background output buffer. Access is
* synchronized with the writable object. */
int writeBufLen; /* Size of write buffer. Access is
* synchronized with the writable object. */
int toWrite; /* Current amount to be written. Access is
* synchronized with the writable object. */
int readFlags; /* Flags that are shared with the reader
* thread. Access is synchronized with the
* readable object. */
char extraByte; /* Buffer for extra character consumed by
* reader thread. This byte is shared with the
* reader thread so access must be
* synchronized with the readable object. */
} PipeInfo;
typedef struct ThreadSpecificData {
/*
* The following pointer refers to the head of the list of pipes that are
* being watched for file events.
*/
PipeInfo *firstPipePtr;
} ThreadSpecificData;
static Tcl_ThreadDataKey dataKey;
/*
* The following structure is what is added to the Tcl event queue when pipe
* events are generated.
*/
typedef struct PipeEvent {
Tcl_Event header; /* Information that is standard for all
* events. */
PipeInfo *infoPtr; /* Pointer to pipe info structure. Note that
* we still have to verify that the pipe
* exists before dereferencing this
* pointer. */
} PipeEvent;
/*
* Declarations for functions used only in this file.
*/
static int ApplicationType(Tcl_Interp *interp,
const char *fileName, char *fullName);
static void BuildCommandLine(const char *executable, int argc,
const char **argv, Tcl_DString *linePtr);
static BOOL HasConsole(void);
static int PipeBlockModeProc(ClientData instanceData, int mode);
static void PipeCheckProc(ClientData clientData, int flags);
static int PipeClose2Proc(ClientData instanceData,
Tcl_Interp *interp, int flags);
static int PipeEventProc(Tcl_Event *evPtr, int flags);
static int PipeGetHandleProc(ClientData instanceData,
int direction, ClientData *handlePtr);
static void PipeInit(void);
static int PipeInputProc(ClientData instanceData, char *buf,
int toRead, int *errorCode);
static int PipeOutputProc(ClientData instanceData,
const char *buf, int toWrite, int *errorCode);
static DWORD WINAPI PipeReaderThread(LPVOID arg);
static void PipeSetupProc(ClientData clientData, int flags);
static void PipeWatchProc(ClientData instanceData, int mask);
static DWORD WINAPI PipeWriterThread(LPVOID arg);
static int TempFileName(WCHAR name[MAX_PATH]);
static int WaitForRead(PipeInfo *infoPtr, int blocking);
static void PipeThreadActionProc(ClientData instanceData,
int action);
/*
* This structure describes the channel type structure for command pipe based
* I/O.
*/
static Tcl_ChannelType pipeChannelType = {
"pipe", /* Type name. */
TCL_CHANNEL_VERSION_5, /* v5 channel */
TCL_CLOSE2PROC, /* Close proc. */
PipeInputProc, /* Input proc. */
PipeOutputProc, /* Output proc. */
NULL, /* Seek proc. */
NULL, /* Set option proc. */
NULL, /* Get option proc. */
PipeWatchProc, /* Set up notifier to watch the channel. */
PipeGetHandleProc, /* Get an OS handle from channel. */
PipeClose2Proc, /* close2proc */
PipeBlockModeProc, /* Set blocking or non-blocking mode.*/
NULL, /* flush proc. */
NULL, /* handler proc. */
NULL, /* wide seek proc */
PipeThreadActionProc, /* thread action proc */
NULL, /* truncate */
};
/*
*----------------------------------------------------------------------
*
* PipeInit --
*
* This function initializes the static variables for this file.
*
* Results:
* None.
*
* Side effects:
* Creates a new event source.
*
*----------------------------------------------------------------------
*/
static void
PipeInit(void)
{
ThreadSpecificData *tsdPtr;
/*
* Check the initialized flag first, then check again in the mutex. This
* is a speed enhancement.
*/
if (!initialized) {
Tcl_MutexLock(&pipeMutex);
if (!initialized) {
initialized = 1;
procList = NULL;
}
Tcl_MutexUnlock(&pipeMutex);
}
tsdPtr = (ThreadSpecificData *)TclThreadDataKeyGet(&dataKey);
if (tsdPtr == NULL) {
tsdPtr = TCL_TSD_INIT(&dataKey);
tsdPtr->firstPipePtr = NULL;
Tcl_CreateEventSource(PipeSetupProc, PipeCheckProc, NULL);
}
}
/*
*----------------------------------------------------------------------
*
* TclpFinalizePipes --
*
* This function is called from Tcl_FinalizeThread to finalize the
* platform specific pipe subsystem.
*
* Results:
* None.
*
* Side effects:
* Removes the pipe event source.
*
*----------------------------------------------------------------------
*/
void
TclpFinalizePipes(void)
{
ThreadSpecificData *tsdPtr;
tsdPtr = (ThreadSpecificData *)TclThreadDataKeyGet(&dataKey);
if (tsdPtr != NULL) {
Tcl_DeleteEventSource(PipeSetupProc, PipeCheckProc, NULL);
}
}
/*
*----------------------------------------------------------------------
*
* PipeSetupProc --
*
* This function is invoked before Tcl_DoOneEvent blocks waiting for an
* event.
*
* Results:
* None.
*
* Side effects:
* Adjusts the block time if needed.
*
*----------------------------------------------------------------------
*/
void
PipeSetupProc(
ClientData data, /* Not used. */
int flags) /* Event flags as passed to Tcl_DoOneEvent. */
{
PipeInfo *infoPtr;
Tcl_Time blockTime = { 0, 0 };
int block = 1;
WinFile *filePtr;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (!(flags & TCL_FILE_EVENTS)) {
return;
}
/*
* Look to see if any events are already pending. If they are, poll.
*/
for (infoPtr = tsdPtr->firstPipePtr; infoPtr != NULL;
infoPtr = infoPtr->nextPtr) {
if (infoPtr->watchMask & TCL_WRITABLE) {
filePtr = (WinFile*) infoPtr->writeFile;
if (WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT) {
block = 0;
}
}
if (infoPtr->watchMask & TCL_READABLE) {
filePtr = (WinFile*) infoPtr->readFile;
if (WaitForRead(infoPtr, 0) >= 0) {
block = 0;
}
}
}
if (!block) {
Tcl_SetMaxBlockTime(&blockTime);
}
}
/*
*----------------------------------------------------------------------
*
* PipeCheckProc --
*
* This function is called by Tcl_DoOneEvent to check the pipe event
* source for events.
*
* Results:
* None.
*
* Side effects:
* May queue an event.
*
*----------------------------------------------------------------------
*/
static void
PipeCheckProc(
ClientData data, /* Not used. */
int flags) /* Event flags as passed to Tcl_DoOneEvent. */
{
PipeInfo *infoPtr;
PipeEvent *evPtr;
WinFile *filePtr;
int needEvent;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (!(flags & TCL_FILE_EVENTS)) {
return;
}
/*
* Queue events for any ready pipes that don't already have events queued.
*/
for (infoPtr = tsdPtr->firstPipePtr; infoPtr != NULL;
infoPtr = infoPtr->nextPtr) {
if (infoPtr->flags & PIPE_PENDING) {
continue;
}
/*
* Queue an event if the pipe is signaled for reading or writing.
*/
needEvent = 0;
filePtr = (WinFile*) infoPtr->writeFile;
if ((infoPtr->watchMask & TCL_WRITABLE) &&
(WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT)) {
needEvent = 1;
}
filePtr = (WinFile*) infoPtr->readFile;
if ((infoPtr->watchMask & TCL_READABLE) &&
(WaitForRead(infoPtr, 0) >= 0)) {
needEvent = 1;
}
if (needEvent) {
infoPtr->flags |= PIPE_PENDING;
evPtr = (PipeEvent *) ckalloc(sizeof(PipeEvent));
evPtr->header.proc = PipeEventProc;
evPtr->infoPtr = infoPtr;
Tcl_QueueEvent((Tcl_Event *) evPtr, TCL_QUEUE_TAIL);
}
}
}
/*
*----------------------------------------------------------------------
*
* TclWinMakeFile --
*
* This function constructs a new TclFile from a given data and type
* value.
*
* Results:
* Returns a newly allocated WinFile as a TclFile.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TclFile
TclWinMakeFile(
HANDLE handle) /* Type-specific data. */
{
WinFile *filePtr;
filePtr = (WinFile *) ckalloc(sizeof(WinFile));
filePtr->type = WIN_FILE;
filePtr->handle = handle;
return (TclFile)filePtr;
}
/*
*----------------------------------------------------------------------
*
* TempFileName --
*
* Gets a temporary file name and deals with the fact that the temporary
* file path provided by Windows may not actually exist if the TMP or
* TEMP environment variables refer to a non-existent directory.
*
* Results:
* 0 if error, non-zero otherwise. If non-zero is returned, the name
* buffer will be filled with a name that can be used to construct a
* temporary file.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static int
TempFileName(
WCHAR name[MAX_PATH]) /* Buffer in which name for temporary file
* gets stored. */
{
TCHAR *prefix;
prefix = (tclWinProcs->useWide) ? (TCHAR *) L"TCL" : (TCHAR *) "TCL";
if ((*tclWinProcs->getTempPathProc)(MAX_PATH, name) != 0) {
if ((*tclWinProcs->getTempFileNameProc)((TCHAR *) name, prefix, 0,
name) != 0) {
return 1;
}
}
if (tclWinProcs->useWide) {
((WCHAR *) name)[0] = '.';
((WCHAR *) name)[1] = '\0';
} else {
((char *) name)[0] = '.';
((char *) name)[1] = '\0';
}
return (*tclWinProcs->getTempFileNameProc)((TCHAR *) name, prefix, 0,
name);
}
/*
*----------------------------------------------------------------------
*
* TclpMakeFile --
*
* Make a TclFile from a channel.
*
* Results:
* Returns a new TclFile or NULL on failure.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TclFile
TclpMakeFile(
Tcl_Channel channel, /* Channel to get file from. */
int direction) /* Either TCL_READABLE or TCL_WRITABLE. */
{
HANDLE handle;
if (Tcl_GetChannelHandle(channel, direction,
(ClientData *) &handle) == TCL_OK) {
return TclWinMakeFile(handle);
} else {
return (TclFile) NULL;
}
}
/*
*----------------------------------------------------------------------
*
* TclpOpenFile --
*
* This function opens files for use in a pipeline.
*
* Results:
* Returns a newly allocated TclFile structure containing the file
* handle.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TclFile
TclpOpenFile(
const char *path, /* The name of the file to open. */
int mode) /* In what mode to open the file? */
{
HANDLE handle;
DWORD accessMode, createMode, shareMode, flags;
Tcl_DString ds;
const TCHAR *nativePath;
/*
* Map the access bits to the NT access mode.
*/
switch (mode & (O_RDONLY | O_WRONLY | O_RDWR)) {
case O_RDONLY:
accessMode = GENERIC_READ;
break;
case O_WRONLY:
accessMode = GENERIC_WRITE;
break;
case O_RDWR:
accessMode = (GENERIC_READ | GENERIC_WRITE);
break;
default:
TclWinConvertError(ERROR_INVALID_FUNCTION);
return NULL;
}
/*
* Map the creation flags to the NT create mode.
*/
switch (mode & (O_CREAT | O_EXCL | O_TRUNC)) {
case (O_CREAT | O_EXCL):
case (O_CREAT | O_EXCL | O_TRUNC):
createMode = CREATE_NEW;
break;
case (O_CREAT | O_TRUNC):
createMode = CREATE_ALWAYS;
break;
case O_CREAT:
createMode = OPEN_ALWAYS;
break;
case O_TRUNC:
case (O_TRUNC | O_EXCL):
createMode = TRUNCATE_EXISTING;
break;
default:
createMode = OPEN_EXISTING;
break;
}
nativePath = Tcl_WinUtfToTChar(path, -1, &ds);
/*
* If the file is not being created, use the existing file attributes.
*/
flags = 0;
if (!(mode & O_CREAT)) {
flags = (*tclWinProcs->getFileAttributesProc)(nativePath);
if (flags == 0xFFFFFFFF) {
flags = 0;
}
}
/*
* Set up the file sharing mode. We want to allow simultaneous access.
*/
shareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
/*
* Now we get to create the file.
*/
handle = (*tclWinProcs->createFileProc)(nativePath, accessMode,
shareMode, NULL, createMode, flags, NULL);
Tcl_DStringFree(&ds);
if (handle == INVALID_HANDLE_VALUE) {
DWORD err;
err = GetLastError();
if ((err & 0xffffL) == ERROR_OPEN_FAILED) {
err = (mode & O_CREAT) ? ERROR_FILE_EXISTS : ERROR_FILE_NOT_FOUND;
}
TclWinConvertError(err);
return NULL;
}
/*
* Seek to the end of file if we are writing.
*/
if (mode & (O_WRONLY|O_APPEND)) {
SetFilePointer(handle, 0, NULL, FILE_END);
}
return TclWinMakeFile(handle);
}
/*
*----------------------------------------------------------------------
*
* TclpCreateTempFile --
*
* This function opens a unique file with the property that it will be
* deleted when its file handle is closed. The temporary file is created
* in the system temporary directory.
*
* Results:
* Returns a valid TclFile, or NULL on failure.
*
* Side effects:
* Creates a new temporary file.
*
*----------------------------------------------------------------------
*/
TclFile
TclpCreateTempFile(
const char *contents) /* String to write into temp file, or NULL. */
{
WCHAR name[MAX_PATH];
const char *native;
Tcl_DString dstring;
HANDLE handle;
if (TempFileName(name) == 0) {
return NULL;
}
handle = (*tclWinProcs->createFileProc)((TCHAR *) name,
GENERIC_READ | GENERIC_WRITE, 0, NULL, CREATE_ALWAYS,
FILE_ATTRIBUTE_TEMPORARY|FILE_FLAG_DELETE_ON_CLOSE, NULL);
if (handle == INVALID_HANDLE_VALUE) {
goto error;
}
/*
* Write the file out, doing line translations on the way.
*/
if (contents != NULL) {
DWORD result, length;
const char *p;
/*
* Convert the contents from UTF to native encoding
*/
native = Tcl_UtfToExternalDString(NULL, contents, -1, &dstring);
for (p = native; *p != '\0'; p++) {
if (*p == '\n') {
length = p - native;
if (length > 0) {
if (!WriteFile(handle, native, length, &result, NULL)) {
goto error;
}
}
if (!WriteFile(handle, "\r\n", 2, &result, NULL)) {
goto error;
}
native = p+1;
}
}
length = p - native;
if (length > 0) {
if (!WriteFile(handle, native, length, &result, NULL)) {
goto error;
}
}
Tcl_DStringFree(&dstring);
if (SetFilePointer(handle, 0, NULL, FILE_BEGIN) == 0xFFFFFFFF) {
goto error;
}
}
return TclWinMakeFile(handle);
error:
/*
* Free the native representation of the contents if necessary.
*/
if (contents != NULL) {
Tcl_DStringFree(&dstring);
}
TclWinConvertError(GetLastError());
CloseHandle(handle);
(*tclWinProcs->deleteFileProc)((TCHAR *) name);
return NULL;
}
/*
*----------------------------------------------------------------------
*
* TclpTempFileName --
*
* This function returns a unique filename.
*
* Results:
* Returns a valid Tcl_Obj* with refCount 0, or NULL on failure.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
Tcl_Obj *
TclpTempFileName(void)
{
WCHAR fileName[MAX_PATH];
if (TempFileName(fileName) == 0) {
return NULL;
}
return TclpNativeToNormalized((ClientData) fileName);
}
/*
*----------------------------------------------------------------------
*
* TclpCreatePipe --
*
* Creates an anonymous pipe.
*
* Results:
* Returns 1 on success, 0 on failure.
*
* Side effects:
* Creates a pipe.
*
*----------------------------------------------------------------------
*/
int
TclpCreatePipe(
TclFile *readPipe, /* Location to store file handle for read side
* of pipe. */
TclFile *writePipe) /* Location to store file handle for write
* side of pipe. */
{
HANDLE readHandle, writeHandle;
if (CreatePipe(&readHandle, &writeHandle, NULL, 0) != 0) {
*readPipe = TclWinMakeFile(readHandle);
*writePipe = TclWinMakeFile(writeHandle);
return 1;
}
TclWinConvertError(GetLastError());
return 0;
}
/*
*----------------------------------------------------------------------
*
* TclpCloseFile --
*
* Closes a pipeline file handle. These handles are created by
* TclpOpenFile, TclpCreatePipe, or TclpMakeFile.
*
* Results:
* 0 on success, -1 on failure.
*
* Side effects:
* The file is closed and deallocated.
*
*----------------------------------------------------------------------
*/
int
TclpCloseFile(
TclFile file) /* The file to close. */
{
WinFile *filePtr = (WinFile *) file;
switch (filePtr->type) {
case WIN_FILE:
/*
* Don't close the Win32 handle if the handle is a standard channel
* during the thread exit process. Otherwise, one thread may kill the
* stdio of another.
*/
if (!TclInThreadExit()
|| ((GetStdHandle(STD_INPUT_HANDLE) != filePtr->handle)
&& (GetStdHandle(STD_OUTPUT_HANDLE) != filePtr->handle)
&& (GetStdHandle(STD_ERROR_HANDLE) != filePtr->handle))) {
if (filePtr->handle != NULL &&
CloseHandle(filePtr->handle) == FALSE) {
TclWinConvertError(GetLastError());
ckfree((char *) filePtr);
return -1;
}
}
break;
default:
Tcl_Panic("TclpCloseFile: unexpected file type");
}
ckfree((char *) filePtr);
return 0;
}
/*
*--------------------------------------------------------------------------
*
* TclpGetPid --
*
* Given a HANDLE to a child process, return the process id for that
* child process.
*
* Results:
* Returns the process id for the child process. If the pid was not known
* by Tcl, either because the pid was not created by Tcl or the child
* process has already been reaped, -1 is returned.
*
* Side effects:
* None.
*
*--------------------------------------------------------------------------
*/
unsigned long
TclpGetPid(
Tcl_Pid pid) /* The HANDLE of the child process. */
{
ProcInfo *infoPtr;
PipeInit();
Tcl_MutexLock(&pipeMutex);
for (infoPtr = procList; infoPtr != NULL; infoPtr = infoPtr->nextPtr) {
if (infoPtr->hProcess == (HANDLE) pid) {
Tcl_MutexUnlock(&pipeMutex);
return infoPtr->dwProcessId;
}
}
Tcl_MutexUnlock(&pipeMutex);
return (unsigned long) -1;
}
/*
*----------------------------------------------------------------------
*
* TclpCreateProcess --
*
* Create a child process that has the specified files as its standard
* input, output, and error. The child process runs asynchronously under
* Windows NT and Windows 9x, and runs with the same environment
* variables as the creating process.
*
* The complete Windows search path is searched to find the specified
* executable. If an executable by the given name is not found,
* automatically tries appending ".com", ".exe", and ".bat" to the
* executable name.
*
* Results:
* The return value is TCL_ERROR and an error message is left in the
* interp's result if there was a problem creating the child process.
* Otherwise, the return value is TCL_OK and *pidPtr is filled with the
* process id of the child process.
*
* Side effects:
* A process is created.
*
*----------------------------------------------------------------------
*/
int
TclpCreateProcess(
Tcl_Interp *interp, /* Interpreter in which to leave errors that
* occurred when creating the child process.
* Error messages from the child process
* itself are sent to errorFile. */
int argc, /* Number of arguments in following array. */
const char **argv, /* Array of argument strings. argv[0] contains
* the name of the executable converted to
* native format (using the
* Tcl_TranslateFileName call). Additional
* arguments have not been converted. */
TclFile inputFile, /* If non-NULL, gives the file to use as input
* for the child process. If inputFile file is
* not readable or is NULL, the child will
* receive no standard input. */
TclFile outputFile, /* If non-NULL, gives the file that receives
* output from the child process. If
* outputFile file is not writeable or is
* NULL, output from the child will be
* discarded. */
TclFile errorFile, /* If non-NULL, gives the file that receives
* errors from the child process. If errorFile
* file is not writeable or is NULL, errors
* from the child will be discarded. errorFile
* may be the same as outputFile. */
Tcl_Pid *pidPtr) /* If this function is successful, pidPtr is
* filled with the process id of the child
* process. */
{
int result, applType, createFlags;
Tcl_DString cmdLine; /* Complete command line (TCHAR). */
STARTUPINFOA startInfo;
PROCESS_INFORMATION procInfo;
SECURITY_ATTRIBUTES secAtts;
HANDLE hProcess, h, inputHandle, outputHandle, errorHandle;
char execPath[MAX_PATH * TCL_UTF_MAX];
WinFile *filePtr;
PipeInit();
applType = ApplicationType(interp, argv[0], execPath);
if (applType == APPL_NONE) {
return TCL_ERROR;
}
result = TCL_ERROR;
Tcl_DStringInit(&cmdLine);
hProcess = GetCurrentProcess();
/*
* STARTF_USESTDHANDLES must be used to pass handles to child process.
* Using SetStdHandle() and/or dup2() only works when a console mode
* parent process is spawning an attached console mode child process.
*/
ZeroMemory(&startInfo, sizeof(startInfo));
startInfo.cb = sizeof(startInfo);
startInfo.dwFlags = STARTF_USESTDHANDLES;
startInfo.hStdInput = INVALID_HANDLE_VALUE;
startInfo.hStdOutput= INVALID_HANDLE_VALUE;
startInfo.hStdError = INVALID_HANDLE_VALUE;
secAtts.nLength = sizeof(SECURITY_ATTRIBUTES);
secAtts.lpSecurityDescriptor = NULL;
secAtts.bInheritHandle = TRUE;
/*
* We have to check the type of each file, since we cannot duplicate some
* file types.
*/
inputHandle = INVALID_HANDLE_VALUE;
if (inputFile != NULL) {
filePtr = (WinFile *)inputFile;
if (filePtr->type == WIN_FILE) {
inputHandle = filePtr->handle;
}
}
outputHandle = INVALID_HANDLE_VALUE;
if (outputFile != NULL) {
filePtr = (WinFile *)outputFile;
if (filePtr->type == WIN_FILE) {
outputHandle = filePtr->handle;
}
}
errorHandle = INVALID_HANDLE_VALUE;
if (errorFile != NULL) {
filePtr = (WinFile *)errorFile;
if (filePtr->type == WIN_FILE) {
errorHandle = filePtr->handle;
}
}
/*
* Duplicate all the handles which will be passed off as stdin, stdout and
* stderr of the child process. The duplicate handles are set to be
* inheritable, so the child process can use them.
*/
if (inputHandle == INVALID_HANDLE_VALUE) {
/*
* If handle was not set, stdin should return immediate EOF. Under
* Windows95, some applications (both 16 and 32 bit!) cannot read from
* the NUL device; they read from console instead. When running tk,
* this is fatal because the child process would hang forever waiting
* for EOF from the unmapped console window used by the helper
* application.
*
* Fortunately, the helper application detects a closed pipe as an
* immediate EOF and can pass that information to the child process.
*/
if (CreatePipe(&startInfo.hStdInput, &h, &secAtts, 0) != FALSE) {
CloseHandle(h);
}
} else {
DuplicateHandle(hProcess, inputHandle, hProcess, &startInfo.hStdInput,
0, TRUE, DUPLICATE_SAME_ACCESS);
}
if (startInfo.hStdInput == INVALID_HANDLE_VALUE) {
TclWinConvertError(GetLastError());
Tcl_AppendResult(interp, "couldn't duplicate input handle: ",
Tcl_PosixError(interp), (char *) NULL);
goto end;
}
if (outputHandle == INVALID_HANDLE_VALUE) {
/*
* If handle was not set, output should be sent to an infinitely deep
* sink. Under Windows 95, some 16 bit applications cannot have stdout
* redirected to NUL; they send their output to the console instead.
* Some applications, like "more" or "dir /p", when outputting
* multiple pages to the console, also then try and read from the
* console to go the next page. When running tk, this is fatal because
* the child process would hang forever waiting for input from the
* unmapped console window used by the helper application.
*
* Fortunately, the helper application will detect a closed pipe as a
* sink.
*/
if ((TclWinGetPlatformId() == VER_PLATFORM_WIN32_WINDOWS)
&& (applType == APPL_DOS)) {
if (CreatePipe(&h, &startInfo.hStdOutput, &secAtts, 0) != FALSE) {
CloseHandle(h);
}
} else {
startInfo.hStdOutput = CreateFileA("NUL:", GENERIC_WRITE, 0,
&secAtts, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
}
} else {
DuplicateHandle(hProcess, outputHandle, hProcess,
&startInfo.hStdOutput, 0, TRUE, DUPLICATE_SAME_ACCESS);
}
if (startInfo.hStdOutput == INVALID_HANDLE_VALUE) {
TclWinConvertError(GetLastError());
Tcl_AppendResult(interp, "couldn't duplicate output handle: ",
Tcl_PosixError(interp), (char *) NULL);
goto end;
}
if (errorHandle == INVALID_HANDLE_VALUE) {
/*
* If handle was not set, errors should be sent to an infinitely deep
* sink.
*/
startInfo.hStdError = CreateFileA("NUL:", GENERIC_WRITE, 0,
&secAtts, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
} else {
DuplicateHandle(hProcess, errorHandle, hProcess, &startInfo.hStdError,
0, TRUE, DUPLICATE_SAME_ACCESS);
}
if (startInfo.hStdError == INVALID_HANDLE_VALUE) {
TclWinConvertError(GetLastError());
Tcl_AppendResult(interp, "couldn't duplicate error handle: ",
Tcl_PosixError(interp), (char *) NULL);
goto end;
}
/*
* If we do not have a console window, then we must run DOS and WIN32
* console mode applications as detached processes. This tells the loader
* that the child application should not inherit the console, and that it
* should not create a new console window for the child application. The
* child application should get its stdio from the redirection handles
* provided by this application, and run in the background.
*
* If we are starting a GUI process, they don't automatically get a
* console, so it doesn't matter if they are started as foreground or
* detached processes. The GUI window will still pop up to the foreground.
*/
if (TclWinGetPlatformId() == VER_PLATFORM_WIN32_NT) {
if (HasConsole()) {
createFlags = 0;
} else if (applType == APPL_DOS) {
/*
* Under NT, 16-bit DOS applications will not run unless they can
* be attached to a console. If we are running without a console,
* run the 16-bit program as an normal process inside of a hidden
* console application, and then run that hidden console as a
* detached process.
*/
startInfo.wShowWindow = SW_HIDE;
startInfo.dwFlags |= STARTF_USESHOWWINDOW;
createFlags = CREATE_NEW_CONSOLE;
Tcl_DStringAppend(&cmdLine, "cmd.exe /c", -1);
} else {
createFlags = DETACHED_PROCESS;
}
} else {
if (HasConsole()) {
createFlags = 0;
} else {
createFlags = DETACHED_PROCESS;
}
if (applType == APPL_DOS) {
/*
* Under Windows 95, 16-bit DOS applications do not work well with
* pipes:
*
* 1. EOF on a pipe between a detached 16-bit DOS application and
* another application is not seen at the other end of the pipe,
* so the listening process blocks forever on reads. This inablity
* to detect EOF happens when either a 16-bit app or the 32-bit
* app is the listener.
*
* 2. If a 16-bit DOS application (detached or not) blocks when
* writing to a pipe, it will never wake up again, and it
* eventually brings the whole system down around it.
*
* The 16-bit application is run as a normal process inside of a
* hidden helper console app, and this helper may be run as a
* detached process. If any of the stdio handles is a pipe, the
* helper application accumulates information into temp files and
* forwards it to or from the DOS application as appropriate.
* This means that DOS apps must receive EOF from a stdin pipe
* before they will actually begin, and must finish generating
* stdout or stderr before the data will be sent to the next stage
* of the pipe.
*
* The helper app should be located in the same directory as the
* tcl dll.
*/
Tcl_Obj *tclExePtr, *pipeDllPtr;
char *start, *end;
int i, fileExists;
Tcl_DString pipeDll;
if (createFlags != 0) {
startInfo.wShowWindow = SW_HIDE;
startInfo.dwFlags |= STARTF_USESHOWWINDOW;
createFlags = CREATE_NEW_CONSOLE;
}
Tcl_DStringInit(&pipeDll);
Tcl_DStringAppend(&pipeDll, TCL_PIPE_DLL, -1);
tclExePtr = TclGetObjNameOfExecutable();
Tcl_IncrRefCount(tclExePtr);
start = Tcl_GetStringFromObj(tclExePtr, &i);
for (end = start + (i-1); end > start; end--) {
if (*end == '/') {
break;
}
}
if (*end != '/') {
Tcl_AppendResult(interp, "no / in executable path name \"",
start, "\"", (char *) NULL);
Tcl_DecrRefCount(tclExePtr);
Tcl_DStringFree(&pipeDll);
goto end;
}
i = (end - start) + 1;
pipeDllPtr = Tcl_NewStringObj(start, i);
Tcl_AppendToObj(pipeDllPtr, Tcl_DStringValue(&pipeDll), -1);
Tcl_IncrRefCount(pipeDllPtr);
if (Tcl_FSConvertToPathType(interp, pipeDllPtr) != TCL_OK) {
Tcl_Panic("Tcl_FSConvertToPathType failed");
}
fileExists = (Tcl_FSAccess(pipeDllPtr, F_OK) == 0);
if (!fileExists) {
Tcl_AppendResult(interp, "Tcl pipe dll \"",
Tcl_DStringValue(&pipeDll), "\" not found",
(char *) NULL);
Tcl_DecrRefCount(tclExePtr);
Tcl_DecrRefCount(pipeDllPtr);
Tcl_DStringFree(&pipeDll);
goto end;
}
Tcl_DStringAppend(&cmdLine, Tcl_DStringValue(&pipeDll), -1);
Tcl_DecrRefCount(tclExePtr);
Tcl_DecrRefCount(pipeDllPtr);
Tcl_DStringFree(&pipeDll);
}
}
/*
* cmdLine gets the full command line used to invoke the executable,
* including the name of the executable itself. The command line arguments
* in argv[] are stored in cmdLine separated by spaces. Special characters
* in individual arguments from argv[] must be quoted when being stored in
* cmdLine.
*
* When calling any application, bear in mind that arguments that specify
* a path name are not converted. If an argument contains forward slashes
* as path separators, it may or may not be recognized as a path name,
* depending on the program. In general, most applications accept forward
* slashes only as option delimiters and backslashes only as paths.
*
* Additionally, when calling a 16-bit dos or windows application, all
* path names must use the short, cryptic, path format (e.g., using
* ab~1.def instead of "a b.default").
*/
BuildCommandLine(execPath, argc, argv, &cmdLine);
if ((*tclWinProcs->createProcessProc)(NULL,
(TCHAR *) Tcl_DStringValue(&cmdLine), NULL, NULL, TRUE,
(DWORD) createFlags, NULL, NULL, &startInfo, &procInfo) == 0) {
TclWinConvertError(GetLastError());
Tcl_AppendResult(interp, "couldn't execute \"", argv[0],
"\": ", Tcl_PosixError(interp), (char *) NULL);
goto end;
}
/*
* This wait is used to force the OS to give some time to the DOS process.
*/
if (applType == APPL_DOS) {
WaitForSingleObject(procInfo.hProcess, 50);
}
/*
* "When an application spawns a process repeatedly, a new thread instance
* will be created for each process but the previous instances may not be
* cleaned up. This results in a significant virtual memory loss each time
* the process is spawned. If there is a WaitForInputIdle() call between
* CreateProcess() and CloseHandle(), the problem does not occur." PSS ID
* Number: Q124121
*/
WaitForInputIdle(procInfo.hProcess, 5000);
CloseHandle(procInfo.hThread);
*pidPtr = (Tcl_Pid) procInfo.hProcess;
if (*pidPtr != 0) {
TclWinAddProcess(procInfo.hProcess, procInfo.dwProcessId);
}
result = TCL_OK;
end:
Tcl_DStringFree(&cmdLine);
if (startInfo.hStdInput != INVALID_HANDLE_VALUE) {
CloseHandle(startInfo.hStdInput);
}
if (startInfo.hStdOutput != INVALID_HANDLE_VALUE) {
CloseHandle(startInfo.hStdOutput);
}
if (startInfo.hStdError != INVALID_HANDLE_VALUE) {
CloseHandle(startInfo.hStdError);
}
return result;
}
/*
*----------------------------------------------------------------------
*
* HasConsole --
*
* Determines whether the current application is attached to a console.
*
* Results:
* Returns TRUE if this application has a console, else FALSE.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static BOOL
HasConsole(void)
{
HANDLE handle;
handle = CreateFileA("CONOUT$", GENERIC_WRITE, FILE_SHARE_WRITE,
NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (handle != INVALID_HANDLE_VALUE) {
CloseHandle(handle);
return TRUE;
} else {
return FALSE;
}
}
/*
*--------------------------------------------------------------------
*
* ApplicationType --
*
* Search for the specified program and identify if it refers to a DOS,
* Windows 3.X, or Win32 program. Used to determine how to invoke a
* program, or if it can even be invoked.
*
* It is possible to almost positively identify DOS and Windows
* applications that contain the appropriate magic numbers. However, DOS
* .com files do not seem to contain a magic number; if the program name
* ends with .com and could not be identified as a Windows .com file, it
* will be assumed to be a DOS application, even if it was just random
* data. If the program name does not end with .com, no such assumption
* is made.
*
* The Win32 function GetBinaryType incorrectly identifies any junk file
* that ends with .exe as a dos executable and some executables that
* don't end with .exe as not executable. Plus it doesn't exist under
* win95, so I won't feel bad about reimplementing functionality.
*
* Results:
* The return value is one of APPL_DOS, APPL_WIN3X, or APPL_WIN32 if the
* filename referred to the corresponding application type. If the file
* name could not be found or did not refer to any known application
* type, APPL_NONE is returned and an error message is left in interp.
* .bat files are identified as APPL_DOS.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static int
ApplicationType(
Tcl_Interp *interp, /* Interp, for error message. */
const char *originalName, /* Name of the application to find. */
char fullName[]) /* Filled with complete path to
* application. */
{
int applType, i, nameLen, found;
HANDLE hFile;
TCHAR *rest;
char *ext;
char buf[2];
DWORD attr, read;
IMAGE_DOS_HEADER header;
Tcl_DString nameBuf, ds;
const TCHAR *nativeName;
WCHAR nativeFullPath[MAX_PATH];
static char extensions[][5] = {"", ".com", ".exe", ".bat"};
/*
* Look for the program as an external program. First try the name as it
* is, then try adding .com, .exe, and .bat, in that order, to the name,
* looking for an executable.
*
* Using the raw SearchPath() function doesn't do quite what is necessary.
* If the name of the executable already contains a '.' character, it will
* not try appending the specified extension when searching (in other
* words, SearchPath will not find the program "a.b.exe" if the arguments
* specified "a.b" and ".exe"). So, first look for the file as it is
* named. Then manually append the extensions, looking for a match.
*/
applType = APPL_NONE;
Tcl_DStringInit(&nameBuf);
Tcl_DStringAppend(&nameBuf, originalName, -1);
nameLen = Tcl_DStringLength(&nameBuf);
for (i = 0; i < (int) (sizeof(extensions) / sizeof(extensions[0])); i++) {
Tcl_DStringSetLength(&nameBuf, nameLen);
Tcl_DStringAppend(&nameBuf, extensions[i], -1);
nativeName = Tcl_WinUtfToTChar(Tcl_DStringValue(&nameBuf),
Tcl_DStringLength(&nameBuf), &ds);
found = (*tclWinProcs->searchPathProc)(NULL, nativeName, NULL,
MAX_PATH, nativeFullPath, &rest);
Tcl_DStringFree(&ds);
if (found == 0) {
continue;
}
/*
* Ignore matches on directories or data files, return if identified a
* known type.
*/
attr = (*tclWinProcs->getFileAttributesProc)((TCHAR *) nativeFullPath);
if ((attr == 0xffffffff) || (attr & FILE_ATTRIBUTE_DIRECTORY)) {
continue;
}
strcpy(fullName, Tcl_WinTCharToUtf((TCHAR *) nativeFullPath, -1, &ds));
Tcl_DStringFree(&ds);
ext = strrchr(fullName, '.');
if ((ext != NULL) && (strcasecmp(ext, ".bat") == 0)) {
applType = APPL_DOS;
break;
}
hFile = (*tclWinProcs->createFileProc)((TCHAR *) nativeFullPath,
GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL, NULL);
if (hFile == INVALID_HANDLE_VALUE) {
continue;
}
header.e_magic = 0;
ReadFile(hFile, (void *) &header, sizeof(header), &read, NULL);
if (header.e_magic != IMAGE_DOS_SIGNATURE) {
/*
* Doesn't have the magic number for relocatable executables. If
* filename ends with .com, assume it's a DOS application anyhow.
* Note that we didn't make this assumption at first, because some
* supposed .com files are really 32-bit executables with all the
* magic numbers and everything.
*/
CloseHandle(hFile);
if ((ext != NULL) && (strcasecmp(ext, ".com") == 0)) {
applType = APPL_DOS;
break;
}
continue;
}
if (header.e_lfarlc != sizeof(header)) {
/*
* All Windows 3.X and Win32 and some DOS programs have this value
* set here. If it doesn't, assume that since it already had the
* other magic number it was a DOS application.
*/
CloseHandle(hFile);
applType = APPL_DOS;
break;
}
/*
* The DWORD at header.e_lfanew points to yet another magic number.
*/
buf[0] = '\0';
SetFilePointer(hFile, header.e_lfanew, NULL, FILE_BEGIN);
ReadFile(hFile, (void *) buf, 2, &read, NULL);
CloseHandle(hFile);
if ((buf[0] == 'N') && (buf[1] == 'E')) {
applType = APPL_WIN3X;
} else if ((buf[0] == 'P') && (buf[1] == 'E')) {
applType = APPL_WIN32;
} else {
/*
* Strictly speaking, there should be a test that there is an 'L'
* and 'E' at buf[0..1], to identify the type as DOS, but of
* course we ran into a DOS executable that _doesn't_ have the
* magic number - specifically, one compiled using the Lahey
* Fortran90 compiler.
*/
applType = APPL_DOS;
}
break;
}
Tcl_DStringFree(&nameBuf);
if (applType == APPL_NONE) {
TclWinConvertError(GetLastError());
Tcl_AppendResult(interp, "couldn't execute \"", originalName,
"\": ", Tcl_PosixError(interp), (char *) NULL);
return APPL_NONE;
}
if ((applType == APPL_DOS) || (applType == APPL_WIN3X)) {
/*
* Replace long path name of executable with short path name for
* 16-bit applications. Otherwise the application may not be able to
* correctly parse its own command line to separate off the
* application name from the arguments.
*/
(*tclWinProcs->getShortPathNameProc)((TCHAR *) nativeFullPath,
nativeFullPath, MAX_PATH);
strcpy(fullName, Tcl_WinTCharToUtf((TCHAR *) nativeFullPath, -1, &ds));
Tcl_DStringFree(&ds);
}
return applType;
}
/*
*----------------------------------------------------------------------
*
* BuildCommandLine --
*
* The command line arguments are stored in linePtr separated by spaces,
* in a form that CreateProcess() understands. Special characters in
* individual arguments from argv[] must be quoted when being stored in
* cmdLine.
*
* Results:
* None.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static void
BuildCommandLine(
const char *executable, /* Full path of executable (including
* extension). Replacement for argv[0]. */
int argc, /* Number of arguments. */
const char **argv, /* Argument strings in UTF. */
Tcl_DString *linePtr) /* Initialized Tcl_DString that receives the
* command line (TCHAR). */
{
const char *arg, *start, *special;
int quote, i;
Tcl_DString ds;
Tcl_DStringInit(&ds);
/*
* Prime the path. Add a space separator if we were primed with something.
*/
Tcl_DStringAppend(&ds, Tcl_DStringValue(linePtr), -1);
if (Tcl_DStringLength(linePtr) > 0) {
Tcl_DStringAppend(&ds, " ", 1);
}
for (i = 0; i < argc; i++) {
if (i == 0) {
arg = executable;
} else {
arg = argv[i];
Tcl_DStringAppend(&ds, " ", 1);
}
quote = 0;
if (arg[0] == '\0') {
quote = 1;
} else {
int count;
Tcl_UniChar ch;
for (start = arg; *start != '\0'; start += count) {
count = Tcl_UtfToUniChar(start, &ch);
if (Tcl_UniCharIsSpace(ch)) { /* INTL: ISO space. */
quote = 1;
break;
}
}
}
if (quote) {
Tcl_DStringAppend(&ds, "\"", 1);
}
start = arg;
for (special = arg; ; ) {
if ((*special == '\\') && (special[1] == '\\' ||
special[1] == '"' || (quote && special[1] == '\0'))) {
Tcl_DStringAppend(&ds, start, (int) (special - start));
start = special;
while (1) {
special++;
if (*special == '"' || (quote && *special == '\0')) {
/*
* N backslashes followed a quote -> insert N * 2 + 1
* backslashes then a quote.
*/
Tcl_DStringAppend(&ds, start,
(int) (special - start));
break;
}
if (*special != '\\') {
break;
}
}
Tcl_DStringAppend(&ds, start, (int) (special - start));
start = special;
}
if (*special == '"') {
Tcl_DStringAppend(&ds, start, (int) (special - start));
Tcl_DStringAppend(&ds, "\\\"", 2);
start = special + 1;
}
if (*special == '\0') {
break;
}
special++;
}
Tcl_DStringAppend(&ds, start, (int) (special - start));
if (quote) {
Tcl_DStringAppend(&ds, "\"", 1);
}
}
Tcl_DStringFree(linePtr);
Tcl_WinUtfToTChar(Tcl_DStringValue(&ds), Tcl_DStringLength(&ds), linePtr);
Tcl_DStringFree(&ds);
}
/*
*----------------------------------------------------------------------
*
* TclpCreateCommandChannel --
*
* This function is called by Tcl_OpenCommandChannel to perform the
* platform specific channel initialization for a command channel.
*
* Results:
* Returns a new channel or NULL on failure.
*
* Side effects:
* Allocates a new channel.
*
*----------------------------------------------------------------------
*/
Tcl_Channel
TclpCreateCommandChannel(
TclFile readFile, /* If non-null, gives the file for reading. */
TclFile writeFile, /* If non-null, gives the file for writing. */
TclFile errorFile, /* If non-null, gives the file where errors
* can be read. */
int numPids, /* The number of pids in the pid array. */
Tcl_Pid *pidPtr) /* An array of process identifiers. */
{
char channelName[16 + TCL_INTEGER_SPACE];
int channelId;
DWORD id;
PipeInfo *infoPtr = (PipeInfo *) ckalloc((unsigned) sizeof(PipeInfo));
PipeInit();
infoPtr->watchMask = 0;
infoPtr->flags = 0;
infoPtr->readFlags = 0;
infoPtr->readFile = readFile;
infoPtr->writeFile = writeFile;
infoPtr->errorFile = errorFile;
infoPtr->numPids = numPids;
infoPtr->pidPtr = pidPtr;
infoPtr->writeBuf = 0;
infoPtr->writeBufLen = 0;
infoPtr->writeError = 0;
infoPtr->channel = (Tcl_Channel) NULL;
/*
* Use one of the fds associated with the channel as the channel id.
*/
if (readFile) {
channelId = (int) ((WinFile*)readFile)->handle;
} else if (writeFile) {
channelId = (int) ((WinFile*)writeFile)->handle;
} else if (errorFile) {
channelId = (int) ((WinFile*)errorFile)->handle;
} else {
channelId = 0;
}
infoPtr->validMask = 0;
infoPtr->threadId = Tcl_GetCurrentThread();
if (readFile != NULL) {
/*
* Start the background reader thread.
*/
infoPtr->readable = CreateEvent(NULL, TRUE, TRUE, NULL);
infoPtr->startReader = CreateEvent(NULL, FALSE, FALSE, NULL);
infoPtr->stopReader = CreateEvent(NULL, TRUE, FALSE, NULL);
infoPtr->readThread = CreateThread(NULL, 256, PipeReaderThread,
infoPtr, 0, &id);
SetThreadPriority(infoPtr->readThread, THREAD_PRIORITY_HIGHEST);
infoPtr->validMask |= TCL_READABLE;
} else {
infoPtr->readThread = 0;
}
if (writeFile != NULL) {
/*
* Start the background writer thread.
*/
infoPtr->writable = CreateEvent(NULL, TRUE, TRUE, NULL);
infoPtr->startWriter = CreateEvent(NULL, FALSE, FALSE, NULL);
infoPtr->stopWriter = CreateEvent(NULL, TRUE, FALSE, NULL);
infoPtr->writeThread = CreateThread(NULL, 256, PipeWriterThread,
infoPtr, 0, &id);
SetThreadPriority(infoPtr->readThread, THREAD_PRIORITY_HIGHEST);
infoPtr->validMask |= TCL_WRITABLE;
}
/*
* For backward compatibility with previous versions of Tcl, we use
* "file%d" as the base name for pipes even though it would be more
* natural to use "pipe%d". Use the pointer to keep the channel names
* unique, in case channels share handles (stdin/stdout).
*/
wsprintfA(channelName, "file%lx", infoPtr);
infoPtr->channel = Tcl_CreateChannel(&pipeChannelType, channelName,
(ClientData) infoPtr, infoPtr->validMask);
/*
* Pipes have AUTO translation mode on Windows and ^Z eof char, which
* means that a ^Z will be appended to them at close. This is needed for
* Windows programs that expect a ^Z at EOF.
*/
Tcl_SetChannelOption((Tcl_Interp *) NULL, infoPtr->channel,
"-translation", "auto");
Tcl_SetChannelOption((Tcl_Interp *) NULL, infoPtr->channel,
"-eofchar", "\032 {}");
return infoPtr->channel;
}
/*
*----------------------------------------------------------------------
*
* TclGetAndDetachPids --
*
* Stores a list of the command PIDs for a command channel in the
* interp's result.
*
* Results:
* None.
*
* Side effects:
* Modifies the interp's result.
*
*----------------------------------------------------------------------
*/
void
TclGetAndDetachPids(
Tcl_Interp *interp,
Tcl_Channel chan)
{
PipeInfo *pipePtr;
const Tcl_ChannelType *chanTypePtr;
int i;
char buf[TCL_INTEGER_SPACE];
/*
* Punt if the channel is not a command channel.
*/
chanTypePtr = Tcl_GetChannelType(chan);
if (chanTypePtr != &pipeChannelType) {
return;
}
pipePtr = (PipeInfo *) Tcl_GetChannelInstanceData(chan);
for (i = 0; i < pipePtr->numPids; i++) {
wsprintfA(buf, "%lu", TclpGetPid(pipePtr->pidPtr[i]));
Tcl_AppendElement(interp, buf);
Tcl_DetachPids(1, &(pipePtr->pidPtr[i]));
}
if (pipePtr->numPids > 0) {
ckfree((char *) pipePtr->pidPtr);
pipePtr->numPids = 0;
}
}
/*
*----------------------------------------------------------------------
*
* PipeBlockModeProc --
*
* Set blocking or non-blocking mode on channel.
*
* Results:
* 0 if successful, errno when failed.
*
* Side effects:
* Sets the device into blocking or non-blocking mode.
*
*----------------------------------------------------------------------
*/
static int
PipeBlockModeProc(
ClientData instanceData, /* Instance data for channel. */
int mode) /* TCL_MODE_BLOCKING or
* TCL_MODE_NONBLOCKING. */
{
PipeInfo *infoPtr = (PipeInfo *) instanceData;
/*
* Pipes on Windows can not be switched between blocking and nonblocking,
* hence we have to emulate the behavior. This is done in the input
* function by checking against a bit in the state. We set or unset the
* bit here to cause the input function to emulate the correct behavior.
*/
if (mode == TCL_MODE_NONBLOCKING) {
infoPtr->flags |= PIPE_ASYNC;
} else {
infoPtr->flags &= ~(PIPE_ASYNC);
}
return 0;
}
/*
*----------------------------------------------------------------------
*
* PipeClose2Proc --
*
* Closes a pipe based IO channel.
*
* Results:
* 0 on success, errno otherwise.
*
* Side effects:
* Closes the physical channel.
*
*----------------------------------------------------------------------
*/
static int
PipeClose2Proc(
ClientData instanceData, /* Pointer to PipeInfo structure. */
Tcl_Interp *interp, /* For error reporting. */
int flags) /* Flags that indicate which side to close. */
{
PipeInfo *pipePtr = (PipeInfo *) instanceData;
Tcl_Channel errChan;
int errorCode, result;
PipeInfo *infoPtr, **nextPtrPtr;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
DWORD exitCode;
errorCode = 0;
result = 0;
if ((!flags || flags == TCL_CLOSE_READ) && (pipePtr->readFile != NULL)) {
/*
* Clean up the background thread if necessary. Note that this must be
* done before we can close the file, since the thread may be blocking
* trying to read from the pipe.
*/
if (pipePtr->readThread) {
/*
* The thread may already have closed on its own. Check its exit
* code.
*/
GetExitCodeThread(pipePtr->readThread, &exitCode);
if (exitCode == STILL_ACTIVE) {
/*
* Set the stop event so that if the reader thread is blocked
* in PipeReaderThread on WaitForMultipleEvents, it will exit
* cleanly.
*/
SetEvent(pipePtr->stopReader);
/*
* Wait at most 20 milliseconds for the reader thread to
* close.
*/
if (WaitForSingleObject(pipePtr->readThread,
20) == WAIT_TIMEOUT) {
/*
* The thread must be blocked waiting for the pipe to
* become readable in ReadFile(). There isn't a clean way
* to exit the thread from this condition. We should
* terminate the child process instead to get the reader
* thread to fall out of ReadFile with a FALSE. (below) is
* not the correct way to do this, but will stay here
* until a better solution is found.
*
* Note that we need to guard against terminating the
* thread while it is in the middle of Tcl_ThreadAlert
* because it won't be able to release the notifier lock.
*/
Tcl_MutexLock(&pipeMutex);
/* BUG: this leaks memory */
TerminateThread(pipePtr->readThread, 0);
Tcl_MutexUnlock(&pipeMutex);
}
}
CloseHandle(pipePtr->readThread);
CloseHandle(pipePtr->readable);
CloseHandle(pipePtr->startReader);
CloseHandle(pipePtr->stopReader);
pipePtr->readThread = NULL;
}
if (TclpCloseFile(pipePtr->readFile) != 0) {
errorCode = errno;
}
pipePtr->validMask &= ~TCL_READABLE;
pipePtr->readFile = NULL;
}
if ((!flags || flags & TCL_CLOSE_WRITE)
&& (pipePtr->writeFile != NULL)) {
if (pipePtr->writeThread) {
/*
* Wait for the writer thread to finish the current buffer, then
* terminate the thread and close the handles. If the channel is
* nonblocking, there should be no pending write operations.
*/
WaitForSingleObject(pipePtr->writable, INFINITE);
/*
* The thread may already have closed on it's own. Check its exit
* code.
*/
GetExitCodeThread(pipePtr->writeThread, &exitCode);
if (exitCode == STILL_ACTIVE) {
/*
* Set the stop event so that if the reader thread is blocked
* in PipeReaderThread on WaitForMultipleEvents, it will exit
* cleanly.
*/
SetEvent(pipePtr->stopWriter);
/*
* Wait at most 20 milliseconds for the reader thread to
* close.
*/
if (WaitForSingleObject(pipePtr->writeThread,
20) == WAIT_TIMEOUT) {
/*
* The thread must be blocked waiting for the pipe to
* consume input in WriteFile(). There isn't a clean way
* to exit the thread from this condition. We should
* terminate the child process instead to get the writer
* thread to fall out of WriteFile with a FALSE. (below)
* is not the correct way to do this, but will stay here
* until a better solution is found.
*
* Note that we need to guard against terminating the
* thread while it is in the middle of Tcl_ThreadAlert
* because it won't be able to release the notifier lock.
*/
Tcl_MutexLock(&pipeMutex);
/* BUG: this leaks memory */
TerminateThread(pipePtr->writeThread, 0);
Tcl_MutexUnlock(&pipeMutex);
}
}
CloseHandle(pipePtr->writeThread);
CloseHandle(pipePtr->writable);
CloseHandle(pipePtr->startWriter);
CloseHandle(pipePtr->stopWriter);
pipePtr->writeThread = NULL;
}
if (TclpCloseFile(pipePtr->writeFile) != 0) {
if (errorCode == 0) {
errorCode = errno;
}
}
pipePtr->validMask &= ~TCL_WRITABLE;
pipePtr->writeFile = NULL;
}
pipePtr->watchMask &= pipePtr->validMask;
/*
* Don't free the channel if any of the flags were set.
*/
if (flags) {
return errorCode;
}
/*
* Remove the file from the list of watched files.
*/
for (nextPtrPtr = &(tsdPtr->firstPipePtr), infoPtr = *nextPtrPtr;
infoPtr != NULL;
nextPtrPtr = &infoPtr->nextPtr, infoPtr = *nextPtrPtr) {
if (infoPtr == (PipeInfo *)pipePtr) {
*nextPtrPtr = infoPtr->nextPtr;
break;
}
}
if ((pipePtr->flags & PIPE_ASYNC) || TclInExit()) {
/*
* If the channel is non-blocking or Tcl is being cleaned up, just
* detach the children PIDs, reap them (important if we are in a
* dynamic load module), and discard the errorFile.
*/
Tcl_DetachPids(pipePtr->numPids, pipePtr->pidPtr);
Tcl_ReapDetachedProcs();
if (pipePtr->errorFile) {
if (TclpCloseFile(pipePtr->errorFile) != 0) {
if (errorCode == 0) {
errorCode = errno;
}
}
}
result = 0;
} else {
/*
* Wrap the error file into a channel and give it to the cleanup
* routine.
*/
if (pipePtr->errorFile) {
WinFile *filePtr;
filePtr = (WinFile*)pipePtr->errorFile;
errChan = Tcl_MakeFileChannel((ClientData) filePtr->handle,
TCL_READABLE);
ckfree((char *) filePtr);
} else {
errChan = NULL;
}
result = TclCleanupChildren(interp, pipePtr->numPids,
pipePtr->pidPtr, errChan);
}
if (pipePtr->numPids > 0) {
ckfree((char *) pipePtr->pidPtr);
}
if (pipePtr->writeBuf != NULL) {
ckfree(pipePtr->writeBuf);
}
ckfree((char*) pipePtr);
if (errorCode == 0) {
return result;
}
return errorCode;
}
/*
*----------------------------------------------------------------------
*
* PipeInputProc --
*
* Reads input from the IO channel into the buffer given. Returns count
* of how many bytes were actually read, and an error indication.
*
* Results:
* A count of how many bytes were read is returned and an error
* indication is returned in an output argument.
*
* Side effects:
* Reads input from the actual channel.
*
*----------------------------------------------------------------------
*/
static int
PipeInputProc(
ClientData instanceData, /* Pipe state. */
char *buf, /* Where to store data read. */
int bufSize, /* How much space is available in the
* buffer? */
int *errorCode) /* Where to store error code. */
{
PipeInfo *infoPtr = (PipeInfo *) instanceData;
WinFile *filePtr = (WinFile*) infoPtr->readFile;
DWORD count, bytesRead = 0;
int result;
*errorCode = 0;
/*
* Synchronize with the reader thread.
*/
result = WaitForRead(infoPtr, (infoPtr->flags & PIPE_ASYNC) ? 0 : 1);
/*
* If an error occurred, return immediately.
*/
if (result == -1) {
*errorCode = errno;
return -1;
}
if (infoPtr->readFlags & PIPE_EXTRABYTE) {
/*
* The reader thread consumed 1 byte as a side effect of waiting so we
* need to move it into the buffer.
*/
*buf = infoPtr->extraByte;
infoPtr->readFlags &= ~PIPE_EXTRABYTE;
buf++;
bufSize--;
bytesRead = 1;
/*
* If further read attempts would block, return what we have.
*/
if (result == 0) {
return bytesRead;
}
}
/*
* Attempt to read bufSize bytes. The read will return immediately if
* there is any data available. Otherwise it will block until at least one
* byte is available or an EOF occurs.
*/
if (ReadFile(filePtr->handle, (LPVOID) buf, (DWORD) bufSize, &count,
(LPOVERLAPPED) NULL) == TRUE) {
return bytesRead + count;
} else if (bytesRead) {
/*
* Ignore errors if we have data to return.
*/
return bytesRead;
}
TclWinConvertError(GetLastError());
if (errno == EPIPE) {
infoPtr->readFlags |= PIPE_EOF;
return 0;
}
*errorCode = errno;
return -1;
}
/*
*----------------------------------------------------------------------
*
* PipeOutputProc --
*
* Writes the given output on the IO channel. Returns count of how many
* characters were actually written, and an error indication.
*
* Results:
* A count of how many characters were written is returned and an error
* indication is returned in an output argument.
*
* Side effects:
* Writes output on the actual channel.
*
*----------------------------------------------------------------------
*/
static int
PipeOutputProc(
ClientData instanceData, /* Pipe state. */
const char *buf, /* The data buffer. */
int toWrite, /* How many bytes to write? */
int *errorCode) /* Where to store error code. */
{
PipeInfo *infoPtr = (PipeInfo *) instanceData;
WinFile *filePtr = (WinFile*) infoPtr->writeFile;
DWORD bytesWritten, timeout;
*errorCode = 0;
timeout = (infoPtr->flags & PIPE_ASYNC) ? 0 : INFINITE;
if (WaitForSingleObject(infoPtr->writable, timeout) == WAIT_TIMEOUT) {
/*
* The writer thread is blocked waiting for a write to complete and
* the channel is in non-blocking mode.
*/
errno = EAGAIN;
goto error;
}
/*
* Check for a background error on the last write.
*/
if (infoPtr->writeError) {
TclWinConvertError(infoPtr->writeError);
infoPtr->writeError = 0;
goto error;
}
if (infoPtr->flags & PIPE_ASYNC) {
/*
* The pipe is non-blocking, so copy the data into the output buffer
* and restart the writer thread.
*/
if (toWrite > infoPtr->writeBufLen) {
/*
* Reallocate the buffer to be large enough to hold the data.
*/
if (infoPtr->writeBuf) {
ckfree(infoPtr->writeBuf);
}
infoPtr->writeBufLen = toWrite;
infoPtr->writeBuf = ckalloc((unsigned int) toWrite);
}
memcpy(infoPtr->writeBuf, buf, (size_t) toWrite);
infoPtr->toWrite = toWrite;
ResetEvent(infoPtr->writable);
SetEvent(infoPtr->startWriter);
bytesWritten = toWrite;
} else {
/*
* In the blocking case, just try to write the buffer directly. This
* avoids an unnecessary copy.
*/
if (WriteFile(filePtr->handle, (LPVOID) buf, (DWORD) toWrite,
&bytesWritten, (LPOVERLAPPED) NULL) == FALSE) {
TclWinConvertError(GetLastError());
goto error;
}
}
return bytesWritten;
error:
*errorCode = errno;
return -1;
}
/*
*----------------------------------------------------------------------
*
* PipeEventProc --
*
* This function is invoked by Tcl_ServiceEvent when a file event reaches
* the front of the event queue. This function invokes Tcl_NotifyChannel
* on the pipe.
*
* Results:
* Returns 1 if the event was handled, meaning it should be removed from
* the queue. Returns 0 if the event was not handled, meaning it should
* stay on the queue. The only time the event isn't handled is if the
* TCL_FILE_EVENTS flag bit isn't set.
*
* Side effects:
* Whatever the notifier callback does.
*
*----------------------------------------------------------------------
*/
static int
PipeEventProc(
Tcl_Event *evPtr, /* Event to service. */
int flags) /* Flags that indicate what events to
* handle, such as TCL_FILE_EVENTS. */
{
PipeEvent *pipeEvPtr = (PipeEvent *)evPtr;
PipeInfo *infoPtr;
WinFile *filePtr;
int mask;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
if (!(flags & TCL_FILE_EVENTS)) {
return 0;
}
/*
* Search through the list of watched pipes for the one whose handle
* matches the event. We do this rather than simply dereferencing the
* handle in the event so that pipes can be deleted while the event is in
* the queue.
*/
for (infoPtr = tsdPtr->firstPipePtr; infoPtr != NULL;
infoPtr = infoPtr->nextPtr) {
if (pipeEvPtr->infoPtr == infoPtr) {
infoPtr->flags &= ~(PIPE_PENDING);
break;
}
}
/*
* Remove stale events.
*/
if (!infoPtr) {
return 1;
}
/*
* Check to see if the pipe is readable. Note that we can't tell if a pipe
* is writable, so we always report it as being writable unless we have
* detected EOF.
*/
filePtr = (WinFile*) ((PipeInfo*)infoPtr)->writeFile;
mask = 0;
if ((infoPtr->watchMask & TCL_WRITABLE) &&
(WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT)) {
mask = TCL_WRITABLE;
}
filePtr = (WinFile*) ((PipeInfo*)infoPtr)->readFile;
if ((infoPtr->watchMask & TCL_READABLE) && (WaitForRead(infoPtr,0) >= 0)) {
if (infoPtr->readFlags & PIPE_EOF) {
mask = TCL_READABLE;
} else {
mask |= TCL_READABLE;
}
}
/*
* Inform the channel of the events.
*/
Tcl_NotifyChannel(infoPtr->channel, infoPtr->watchMask & mask);
return 1;
}
/*
*----------------------------------------------------------------------
*
* PipeWatchProc --
*
* Called by the notifier to set up to watch for events on this channel.
*
* Results:
* None.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static void
PipeWatchProc(
ClientData instanceData, /* Pipe state. */
int mask) /* What events to watch for, OR-ed combination
* of TCL_READABLE, TCL_WRITABLE and
* TCL_EXCEPTION. */
{
PipeInfo **nextPtrPtr, *ptr;
PipeInfo *infoPtr = (PipeInfo *) instanceData;
int oldMask = infoPtr->watchMask;
ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
/*
* Since most of the work is handled by the background threads, we just
* need to update the watchMask and then force the notifier to poll once.
*/
infoPtr->watchMask = mask & infoPtr->validMask;
if (infoPtr->watchMask) {
Tcl_Time blockTime = { 0, 0 };
if (!oldMask) {
infoPtr->nextPtr = tsdPtr->firstPipePtr;
tsdPtr->firstPipePtr = infoPtr;
}
Tcl_SetMaxBlockTime(&blockTime);
} else {
if (oldMask) {
/*
* Remove the pipe from the list of watched pipes.
*/
for (nextPtrPtr = &(tsdPtr->firstPipePtr), ptr = *nextPtrPtr;
ptr != NULL;
nextPtrPtr = &ptr->nextPtr, ptr = *nextPtrPtr) {
if (infoPtr == ptr) {
*nextPtrPtr = ptr->nextPtr;
break;
}
}
}
}
}
/*
*----------------------------------------------------------------------
*
* PipeGetHandleProc --
*
* Called from Tcl_GetChannelHandle to retrieve OS handles from inside a
* command pipeline based channel.
*
* Results:
* Returns TCL_OK with the fd in handlePtr, or TCL_ERROR if there is no
* handle for the specified direction.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static int
PipeGetHandleProc(
ClientData instanceData, /* The pipe state. */
int direction, /* TCL_READABLE or TCL_WRITABLE */
ClientData *handlePtr) /* Where to store the handle. */
{
PipeInfo *infoPtr = (PipeInfo *) instanceData;
WinFile *filePtr;
if (direction == TCL_READABLE && infoPtr->readFile) {
filePtr = (WinFile*) infoPtr->readFile;
*handlePtr = (ClientData) filePtr->handle;
return TCL_OK;
}
if (direction == TCL_WRITABLE && infoPtr->writeFile) {
filePtr = (WinFile*) infoPtr->writeFile;
*handlePtr = (ClientData) filePtr->handle;
return TCL_OK;
}
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* Tcl_WaitPid --
*
* Emulates the waitpid system call.
*
* Results:
* Returns 0 if the process is still alive, -1 on an error, or the pid on
* a clean close.
*
* Side effects:
* Unless WNOHANG is set and the wait times out, the process information
* record will be deleted and the process handle will be closed.
*
*----------------------------------------------------------------------
*/
Tcl_Pid
Tcl_WaitPid(
Tcl_Pid pid,
int *statPtr,
int options)
{
ProcInfo *infoPtr = NULL, **prevPtrPtr;
DWORD flags;
Tcl_Pid result;
DWORD ret, exitCode;
PipeInit();
/*
* If no pid is specified, do nothing.
*/
if (pid == 0) {
*statPtr = 0;
return 0;
}
/*
* Find the process and cut it from the process list.
*/
Tcl_MutexLock(&pipeMutex);
prevPtrPtr = &procList;
for (infoPtr = procList; infoPtr != NULL;
prevPtrPtr = &infoPtr->nextPtr, infoPtr = infoPtr->nextPtr) {
if (infoPtr->hProcess == (HANDLE) pid) {
*prevPtrPtr = infoPtr->nextPtr;
break;
}
}
Tcl_MutexUnlock(&pipeMutex);
/*
* If the pid is not one of the processes we know about (we started it)
* then do nothing.
*/
if (infoPtr == NULL) {
*statPtr = 0;
return 0;
}
/*
* Officially "wait" for it to finish. We either poll (WNOHANG) or wait
* for an infinite amount of time.
*/
if (options & WNOHANG) {
flags = 0;
} else {
flags = INFINITE;
}
ret = WaitForSingleObject(infoPtr->hProcess, flags);
if (ret == WAIT_TIMEOUT) {
*statPtr = 0;
if (options & WNOHANG) {
/*
* Re-insert this infoPtr back on the list.
*/
Tcl_MutexLock(&pipeMutex);
infoPtr->nextPtr = procList;
procList = infoPtr;
Tcl_MutexUnlock(&pipeMutex);
return 0;
} else {
result = 0;
}
} else if (ret == WAIT_OBJECT_0) {
GetExitCodeProcess(infoPtr->hProcess, &exitCode);
/*
* Does the exit code look like one of the exception codes?
*/
switch (exitCode) {
case EXCEPTION_FLT_DENORMAL_OPERAND:
case EXCEPTION_FLT_DIVIDE_BY_ZERO:
case EXCEPTION_FLT_INEXACT_RESULT:
case EXCEPTION_FLT_INVALID_OPERATION:
case EXCEPTION_FLT_OVERFLOW:
case EXCEPTION_FLT_STACK_CHECK:
case EXCEPTION_FLT_UNDERFLOW:
case EXCEPTION_INT_DIVIDE_BY_ZERO:
case EXCEPTION_INT_OVERFLOW:
*statPtr = 0xC0000000 | SIGFPE;
break;
case EXCEPTION_PRIV_INSTRUCTION:
case EXCEPTION_ILLEGAL_INSTRUCTION:
*statPtr = 0xC0000000 | SIGILL;
break;
case EXCEPTION_ACCESS_VIOLATION:
case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
case EXCEPTION_STACK_OVERFLOW:
case EXCEPTION_NONCONTINUABLE_EXCEPTION:
case EXCEPTION_INVALID_DISPOSITION:
case EXCEPTION_GUARD_PAGE:
case EXCEPTION_INVALID_HANDLE:
*statPtr = 0xC0000000 | SIGSEGV;
break;
case EXCEPTION_DATATYPE_MISALIGNMENT:
*statPtr = 0xC0000000 | SIGBUS;
break;
case EXCEPTION_BREAKPOINT:
case EXCEPTION_SINGLE_STEP:
*statPtr = 0xC0000000 | SIGTRAP;
break;
case CONTROL_C_EXIT:
*statPtr = 0xC0000000 | SIGINT;
break;
default:
/*
* Non-exceptional, normal, exit code. Note that the exit code is
* truncated to a signed short range [-32768,32768) whether it
* fits into this range or not.
*
* BUG: Even though the exit code is a DWORD, it is understood by
* convention to be a signed integer, yet there isn't enough room
* to fit this into the POSIX style waitstatus mask without
* truncating it.
*/
*statPtr = exitCode;
break;
}
result = pid;
} else {
errno = ECHILD;
*statPtr = 0xC0000000 | ECHILD;
result = (Tcl_Pid) -1;
}
/*
* Officially close the process handle.
*/
CloseHandle(infoPtr->hProcess);
ckfree((char*)infoPtr);
return result;
}
/*
*----------------------------------------------------------------------
*
* TclWinAddProcess --
*
* Add a process to the process list so that we can use Tcl_WaitPid on
* the process.
*
* Results:
* None
*
* Side effects:
* Adds the specified process handle to the process list so Tcl_WaitPid
* knows about it.
*
*----------------------------------------------------------------------
*/
void
TclWinAddProcess(
void *hProcess, /* Handle to process */
unsigned long id) /* Global process identifier */
{
ProcInfo *procPtr = (ProcInfo *) ckalloc(sizeof(ProcInfo));
PipeInit();
procPtr->hProcess = hProcess;
procPtr->dwProcessId = id;
Tcl_MutexLock(&pipeMutex);
procPtr->nextPtr = procList;
procList = procPtr;
Tcl_MutexUnlock(&pipeMutex);
}
/*
*----------------------------------------------------------------------
*
* Tcl_PidObjCmd --
*
* This function is invoked to process the "pid" Tcl command. See the
* user documentation for details on what it does.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_PidObjCmd(
ClientData dummy, /* Not used. */
Tcl_Interp *interp, /* Current interpreter. */
int objc, /* Number of arguments. */
Tcl_Obj *const *objv) /* Argument strings. */
{
Tcl_Channel chan;
const Tcl_ChannelType *chanTypePtr;
PipeInfo *pipePtr;
int i;
Tcl_Obj *resultPtr;
char buf[TCL_INTEGER_SPACE];
if (objc > 2) {
Tcl_WrongNumArgs(interp, 1, objv, "?channelId?");
return TCL_ERROR;
}
if (objc == 1) {
wsprintfA(buf, "%lu", (unsigned long) getpid());
Tcl_SetObjResult(interp, Tcl_NewStringObj(buf, -1));
} else {
chan = Tcl_GetChannel(interp, Tcl_GetStringFromObj(objv[1], NULL),
NULL);
if (chan == (Tcl_Channel) NULL) {
return TCL_ERROR;
}
chanTypePtr = Tcl_GetChannelType(chan);
if (chanTypePtr != &pipeChannelType) {
return TCL_OK;
}
pipePtr = (PipeInfo *) Tcl_GetChannelInstanceData(chan);
resultPtr = Tcl_NewObj();
for (i = 0; i < pipePtr->numPids; i++) {
wsprintfA(buf, "%lu", TclpGetPid(pipePtr->pidPtr[i]));
Tcl_ListObjAppendElement(/*interp*/ NULL, resultPtr,
Tcl_NewStringObj(buf, -1));
}
Tcl_SetObjResult(interp, resultPtr);
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* WaitForRead --
*
* Wait until some data is available, the pipe is at EOF or the reader
* thread is blocked waiting for data (if the channel is in non-blocking
* mode).
*
* Results:
* Returns 1 if pipe is readable. Returns 0 if there is no data on the
* pipe, but there is buffered data. Returns -1 if an error occurred. If
* an error occurred, the threads may not be synchronized.
*
* Side effects:
* Updates the shared state flags and may consume 1 byte of data from the
* pipe. If no error occurred, the reader thread is blocked waiting for a
* signal from the main thread.
*
*----------------------------------------------------------------------
*/
static int
WaitForRead(
PipeInfo *infoPtr, /* Pipe state. */
int blocking) /* Indicates whether call should be blocking
* or not. */
{
DWORD timeout, count;
HANDLE *handle = ((WinFile *) infoPtr->readFile)->handle;
while (1) {
/*
* Synchronize with the reader thread.
*/
timeout = blocking ? INFINITE : 0;
if (WaitForSingleObject(infoPtr->readable, timeout) == WAIT_TIMEOUT) {
/*
* The reader thread is blocked waiting for data and the channel
* is in non-blocking mode.
*/
errno = EAGAIN;
return -1;
}
/*
* At this point, the two threads are synchronized, so it is safe to
* access shared state.
*/
/*
* If the pipe has hit EOF, it is always readable.
*/
if (infoPtr->readFlags & PIPE_EOF) {
return 1;
}
/*
* Check to see if there is any data sitting in the pipe.
*/
if (PeekNamedPipe(handle, (LPVOID) NULL, (DWORD) 0,
(LPDWORD) NULL, &count, (LPDWORD) NULL) != TRUE) {
TclWinConvertError(GetLastError());
/*
* Check to see if the peek failed because of EOF.
*/
if (errno == EPIPE) {
infoPtr->readFlags |= PIPE_EOF;
return 1;
}
/*
* Ignore errors if there is data in the buffer.
*/
if (infoPtr->readFlags & PIPE_EXTRABYTE) {
return 0;
} else {
return -1;
}
}
/*
* We found some data in the pipe, so it must be readable.
*/
if (count > 0) {
return 1;
}
/*
* The pipe isn't readable, but there is some data sitting in the
* buffer, so return immediately.
*/
if (infoPtr->readFlags & PIPE_EXTRABYTE) {
return 0;
}
/*
* There wasn't any data available, so reset the thread and try again.
*/
ResetEvent(infoPtr->readable);
SetEvent(infoPtr->startReader);
}
}
/*
*----------------------------------------------------------------------
*
* PipeReaderThread --
*
* This function runs in a separate thread and waits for input to become
* available on a pipe.
*
* Results:
* None.
*
* Side effects:
* Signals the main thread when input become available. May cause the
* main thread to wake up by posting a message. May consume one byte from
* the pipe for each wait operation. Will cause a memory leak of ~4k, if
* forcefully terminated with TerminateThread().
*
*----------------------------------------------------------------------
*/
static DWORD WINAPI
PipeReaderThread(
LPVOID arg)
{
PipeInfo *infoPtr = (PipeInfo *)arg;
HANDLE *handle = ((WinFile *) infoPtr->readFile)->handle;
DWORD count, err;
int done = 0;
HANDLE wEvents[2];
DWORD waitResult;
wEvents[0] = infoPtr->stopReader;
wEvents[1] = infoPtr->startReader;
while (!done) {
/*
* Wait for the main thread to signal before attempting to wait on the
* pipe becoming readable.
*/
waitResult = WaitForMultipleObjects(2, wEvents, FALSE, INFINITE);
if (waitResult != (WAIT_OBJECT_0 + 1)) {
/*
* The start event was not signaled. It might be the stop event or
* an error, so exit.
*/
break;
}
/*
* Try waiting for 0 bytes. This will block until some data is
* available on NT, but will return immediately on Win 95. So, if no
* data is available after the first read, we block until we can read
* a single byte off of the pipe.
*/
if (ReadFile(handle, NULL, 0, &count, NULL) == FALSE ||
PeekNamedPipe(handle, NULL, 0, NULL, &count, NULL) == FALSE) {
/*
* The error is a result of an EOF condition, so set the EOF bit
* before signalling the main thread.
*/
err = GetLastError();
if (err == ERROR_BROKEN_PIPE) {
infoPtr->readFlags |= PIPE_EOF;
done = 1;
} else if (err == ERROR_INVALID_HANDLE) {
break;
}
} else if (count == 0) {
if (ReadFile(handle, &(infoPtr->extraByte), 1, &count, NULL)
!= FALSE) {
/*
* One byte was consumed as a side effect of waiting for the
* pipe to become readable.
*/
infoPtr->readFlags |= PIPE_EXTRABYTE;
} else {
err = GetLastError();
if (err == ERROR_BROKEN_PIPE) {
/*
* The error is a result of an EOF condition, so set the
* EOF bit before signalling the main thread.
*/
infoPtr->readFlags |= PIPE_EOF;
done = 1;
} else if (err == ERROR_INVALID_HANDLE) {
break;
}
}
}
/*
* Signal the main thread by signalling the readable event and then
* waking up the notifier thread.
*/
SetEvent(infoPtr->readable);
/*
* Alert the foreground thread. Note that we need to treat this like a
* critical section so the foreground thread does not terminate this
* thread while we are holding a mutex in the notifier code.
*/
Tcl_MutexLock(&pipeMutex);
if (infoPtr->threadId != NULL) {
/*
* TIP #218. When in flight ignore the event, no one will receive
* it anyway.
*/
Tcl_ThreadAlert(infoPtr->threadId);
}
Tcl_MutexUnlock(&pipeMutex);
}
return 0;
}
/*
*----------------------------------------------------------------------
*
* PipeWriterThread --
*
* This function runs in a separate thread and writes data onto a pipe.
*
* Results:
* Always returns 0.
*
* Side effects:
* Signals the main thread when an output operation is completed. May
* cause the main thread to wake up by posting a message.
*
*----------------------------------------------------------------------
*/
static DWORD WINAPI
PipeWriterThread(
LPVOID arg)
{
PipeInfo *infoPtr = (PipeInfo *)arg;
HANDLE *handle = ((WinFile *) infoPtr->writeFile)->handle;
DWORD count, toWrite;
char *buf;
int done = 0;
HANDLE wEvents[2];
DWORD waitResult;
wEvents[0] = infoPtr->stopWriter;
wEvents[1] = infoPtr->startWriter;
while (!done) {
/*
* Wait for the main thread to signal before attempting to write.
*/
waitResult = WaitForMultipleObjects(2, wEvents, FALSE, INFINITE);
if (waitResult != (WAIT_OBJECT_0 + 1)) {
/*
* The start event was not signaled. It might be the stop event or
* an error, so exit.
*/
break;
}
buf = infoPtr->writeBuf;
toWrite = infoPtr->toWrite;
/*
* Loop until all of the bytes are written or an error occurs.
*/
while (toWrite > 0) {
if (WriteFile(handle, buf, toWrite, &count, NULL) == FALSE) {
infoPtr->writeError = GetLastError();
done = 1;
break;
} else {
toWrite -= count;
buf += count;
}
}
/*
* Signal the main thread by signalling the writable event and then
* waking up the notifier thread.
*/
SetEvent(infoPtr->writable);
/*
* Alert the foreground thread. Note that we need to treat this like a
* critical section so the foreground thread does not terminate this
* thread while we are holding a mutex in the notifier code.
*/
Tcl_MutexLock(&pipeMutex);
if (infoPtr->threadId != NULL) {
/*
* TIP #218. When in flight ignore the event, no one will receive
* it anyway.
*/
Tcl_ThreadAlert(infoPtr->threadId);
}
Tcl_MutexUnlock(&pipeMutex);
}
return 0;
}
/*
*----------------------------------------------------------------------
*
* PipeThreadActionProc --
*
* Insert or remove any thread local refs to this channel.
*
* Results:
* None.
*
* Side effects:
* Changes thread local list of valid channels.
*
*----------------------------------------------------------------------
*/
static void
PipeThreadActionProc(
ClientData instanceData,
int action)
{
PipeInfo *infoPtr = (PipeInfo *) instanceData;
/*
* We do not access firstPipePtr in the thread structures. This is not for
* all pipes managed by the thread, but only those we are watching.
* Removal of the filevent handlers before transfer thus takes care of
* this structure.
*/
Tcl_MutexLock(&pipeMutex);
if (action == TCL_CHANNEL_THREAD_INSERT) {
/*
* We can't copy the thread information from the channel when the
* channel is created. At this time the channel back pointer has not
* been set yet. However in that case the threadId has already been
* set by TclpCreateCommandChannel itself, so the structure is still
* good.
*/
PipeInit();
if (infoPtr->channel != NULL) {
infoPtr->threadId = Tcl_GetChannelThread(infoPtr->channel);
}
} else {
infoPtr->threadId = NULL;
}
Tcl_MutexUnlock(&pipeMutex);
}
/*
* Local Variables:
* mode: c
* c-basic-offset: 4
* fill-column: 78
* End:
*/
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