* generic/tclFCmd.c (TclFileMakeDirsCmd): fix to race condition in

	file mkdir (backport from head 2005-06-13) [Bug 1217375]

1 files changed, 31 insertions, 5 deletions

diff --git a/generic/tclFCmd.c b/generic/tclFCmd.c
index a105f6e..0f4d1b0 100644
--- a/generic/tclFCmd.c
+++ b/generic/tclFCmd.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: tclFCmd.c,v 1.20.2.1 2003/06/23 10:21:16 vincentdarley Exp $
+ * RCS: @(#) $Id: tclFCmd.c,v 1.20.2.2 2005/08/17 17:46:36 hobbs Exp $
  */
 
 #include "tclInt.h"
@@ -261,19 +261,45 @@ TclFileMakeDirsCmd(interp, objc, objv)
 		    errfile = target;
 		    goto done;
 		}
-	    } else if ((errno != ENOENT)
-		    || (Tcl_FSCreateDirectory(target) != TCL_OK)) {
+	    } else if (errno != ENOENT) {
+		/*
+		 * If Tcl_FSStat() failed and the error is anything
+		 * other than non-existence of the target, throw the
+		 * error.
+		 */
 		errfile = target;
 		goto done;
+	    } else if (Tcl_FSCreateDirectory(target) != TCL_OK) {
+		/*
+		 * Create might have failed because of being in a race
+		 * condition with another process trying to create the
+		 * same subdirectory.
+		 */
+		if (errno == EEXIST) {
+		    if ((Tcl_FSStat(target, &statBuf) == 0)
+			    && S_ISDIR(statBuf.st_mode)) {
+			/*
+			 * It is a directory that wasn't there before,
+			 * so keep going without error.
+			 */
+			Tcl_ResetResult(interp);
+		    } else {
+			errfile = target;
+			goto done;
+		    }
+		} else {
+		    errfile = target;
+		    goto done;
+		}
 	    }
-	    /* Forget about this sub-path */
+ 	    /* Forget about this sub-path */
 	    Tcl_DecrRefCount(target);
 	    target = NULL;
 	}
 	Tcl_DecrRefCount(split);
 	split = NULL;
     }
-	
+
     done:
     if (errfile != NULL) {
 	Tcl_AppendResult(interp, "can't create directory \"",