TIP #332 IMPLEMENTATION - Half-Close for Bidirectional Channels

1 files changed, 98 insertions, 6 deletions

diff --git a/unix/tclUnixPipe.c b/unix/tclUnixPipe.c
index 967d633..0381764 100644
--- a/unix/tclUnixPipe.c
+++ b/unix/tclUnixPipe.c
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclUnixPipe.c,v 1.45 2008/12/12 16:07:18 ferrieux Exp $
+ * RCS: @(#) $Id: tclUnixPipe.c,v 1.46 2008/12/18 01:14:17 ferrieux Exp $
  */
 
 #include "tclInt.h"
@@ -51,8 +51,10 @@ typedef struct PipeState {
  */
 
 static int		PipeBlockModeProc(ClientData instanceData, int mode);
-static int		PipeCloseProc(ClientData instanceData,
-			    Tcl_Interp *interp);
+static int		PipeClose2Proc(ClientData instanceData,
+			    Tcl_Interp *interp, int flags);
+/* static int		PipeCloseProc(ClientData instanceData,
+   Tcl_Interp *interp); */
 static int		PipeGetHandleProc(ClientData instanceData,
 			    int direction, ClientData *handlePtr);
 static int		PipeInputProc(ClientData instanceData, char *buf,
@@ -71,7 +73,7 @@ static int		SetupStdFile(TclFile file, int type);
 static Tcl_ChannelType pipeChannelType = {
     "pipe",			/* Type name. */
     TCL_CHANNEL_VERSION_5,	/* v5 channel */
-    PipeCloseProc,		/* Close proc. */
+    TCL_CLOSE2PROC,		/* Close proc. */
     PipeInputProc,		/* Input proc. */
     PipeOutputProc,		/* Output proc. */
     NULL,			/* Seek proc. */
@@ -79,7 +81,7 @@ static Tcl_ChannelType pipeChannelType = {
     NULL,			/* Get option proc. */
     PipeWatchProc,		/* Initialize notifier. */
     PipeGetHandleProc,		/* Get OS handles out of channel. */
-    NULL,			/* close2proc. */
+    PipeClose2Proc,		/* close2proc. */
     PipeBlockModeProc,		/* Set blocking or non-blocking mode.*/
     NULL,			/* flush proc. */
     NULL,			/* handler proc. */
@@ -908,7 +910,96 @@ PipeBlockModeProc(
 /*
  *----------------------------------------------------------------------
  *
- * PipeCloseProc --
+ * PipeClose2Proc
+ *
+ *	This function is invoked by the generic IO level to perform
+ *	pipeline-type-specific half or full-close.
+ *
+ * Results:
+ *	0 on success, errno otherwise.
+ *
+ * Side effects:
+ *	Closes the command pipeline channel.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PipeClose2Proc(
+    ClientData instanceData,	/* The pipe to close. */
+    Tcl_Interp *interp,		/* For error reporting. */
+    int flags)			/* Flags that indicate which side to close. */
+{
+    PipeState *pipePtr= (PipeState *) instanceData;
+    Tcl_Channel errChan;
+    int errorCode, result;
+
+    errorCode = 0;
+    result = 0;
+
+    if (((!flags)||(flags & TCL_CLOSE_READ)) && (pipePtr->inFile != NULL)) {
+	if (TclpCloseFile(pipePtr->inFile) < 0) {
+	    errorCode = errno;
+	} else {
+	    pipePtr->inFile=NULL;
+	}
+    }
+    if (((!flags)||(flags & TCL_CLOSE_WRITE)) && (pipePtr->outFile != NULL) && (errorCode == 0)) {
+	if (TclpCloseFile(pipePtr->outFile) < 0) {
+	    errorCode = errno;
+	} else {
+	    pipePtr->outFile=NULL;
+	}
+    }
+    
+    /* if half-closing, stop here. */
+    if (flags) {
+		return errorCode;
+    }
+
+    if (pipePtr->isNonBlocking || 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) {
+	    TclpCloseFile(pipePtr->errorFile);
+	}
+    } else {
+	/*
+	 * Wrap the error file into a channel and give it to the cleanup
+	 * routine.
+	 */
+
+	if (pipePtr->errorFile) {
+	    errChan = Tcl_MakeFileChannel(
+		(ClientData) INT2PTR(GetFd(pipePtr->errorFile)), TCL_READABLE);
+	} else {
+	    errChan = NULL;
+	}
+	result = TclCleanupChildren(interp, pipePtr->numPids, pipePtr->pidPtr,
+		errChan);
+    }
+
+    if (pipePtr->numPids != 0) {
+	ckfree((char *) pipePtr->pidPtr);
+    }
+    ckfree((char *) pipePtr);
+    if (errorCode == 0) {
+	return result;
+    }
+    return errorCode;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeCloseProc -- OBSOLETE
  *
  *	This function is invoked by the generic IO level to perform
  *	channel-type-specific cleanup when a command pipeline channel is
@@ -936,6 +1027,7 @@ PipeCloseProc(
     errorCode = 0;
     result = 0;
     pipePtr = (PipeState *) instanceData;
+
     if (pipePtr->inFile) {
 	if (TclpCloseFile(pipePtr->inFile) < 0) {
 	    errorCode = errno;