diff options
| -rw-r--r-- | ChangeLog | 11 | ||||
| -rw-r--r-- | win/tclWinPipe.c | 26 |
2 files changed, 32 insertions, 5 deletions
@@ -1,3 +1,14 @@ +2006-03-14 Andreas Kupries <andreask@activestate.com> + + * win/tclWinPipe.c (Tcl_WaitPid): Backport of fix made to the head + by David Gravereaux in 2004. See ChangeLog entry 2004-01-19. + [Bug 1381436]. + + Fixed a thread-safety problem with the process list. The delayed + cut operation after the wait was going stale by being outside + the list lock. It now cuts within the lock and does a locked + splice for when it needs to instead. [Bug 859820] + 2006-03-13 Don Porter <dgp@users.sourceforge.net> * generic/tclEncoding.c: Report error when an escape encoding diff --git a/win/tclWinPipe.c b/win/tclWinPipe.c index e599b50..624aecc 100644 --- a/win/tclWinPipe.c +++ b/win/tclWinPipe.c @@ -9,7 +9,7 @@ * 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 1.33.2.16 2006/03/10 14:18:54 vasiljevic Exp $ + * RCS: @(#) $Id: tclWinPipe.c,v 1.33.2.17 2006/03/14 20:36:39 andreas_kupries Exp $ */ #include "tclWinInt.h" @@ -885,6 +885,8 @@ TclpGetPid( { ProcInfo *infoPtr; + PipeInit(); + Tcl_MutexLock(&pipeMutex); for (infoPtr = procList; infoPtr != NULL; infoPtr = infoPtr->nextPtr) { if (infoPtr->hProcess == (HANDLE) pid) { @@ -2479,7 +2481,7 @@ Tcl_WaitPid( int *statPtr, int options) { - ProcInfo *infoPtr, **prevPtrPtr; + ProcInfo *infoPtr = NULL, **prevPtrPtr; DWORD flags; Tcl_Pid result; DWORD ret, exitCode; @@ -2496,7 +2498,13 @@ Tcl_WaitPid( } /* - * Find the process on the process list. + * Find the process and cut it from the process list. + * SF Tcl Bug 859820, Backport of its fix. + * SF Tcl Bug 1381436, asking for the backport. + * + * [x] Cutting the infoPtr after the closehandle allows the + * pointer to become stale. We do it here, and compensate if the + * process was not done yet. */ Tcl_MutexLock(&pipeMutex); @@ -2504,6 +2512,7 @@ Tcl_WaitPid( for (infoPtr = procList; infoPtr != NULL; prevPtrPtr = &infoPtr->nextPtr, infoPtr = infoPtr->nextPtr) { if (infoPtr->hProcess == (HANDLE) pid) { + *prevPtrPtr = infoPtr->nextPtr; break; } } @@ -2533,6 +2542,14 @@ Tcl_WaitPid( if (ret == WAIT_TIMEOUT) { *statPtr = 0; if (options & WNOHANG) { + /* + * Re-insert the cut infoPtr back on the list. + * See [x] for explanation. + */ + Tcl_MutexLock(&pipeMutex); + infoPtr->nextPtr = procList; + procList = infoPtr; + Tcl_MutexUnlock(&pipeMutex); return 0; } else { result = 0; @@ -2591,11 +2608,10 @@ Tcl_WaitPid( } /* - * Remove the process from the process list and close the process handle. + * Officially close the process handle. */ CloseHandle(infoPtr->hProcess); - *prevPtrPtr = infoPtr->nextPtr; ckfree((char*)infoPtr); return result; |