* macosx/tclMacOSXNotify.c (Tcl_InitNotifier, Tcl_WaitForEvent): create

	notifier thread lazily upon first call to Tcl_WaitForEvent() rather than
	in Tcl_InitNotifier(). Allows calling exeve() in processes where the
	event loop has not yet been run (Darwin's execve() fails in processes
	with more than one thread), in particular allows embedders to call
	fork() followed by execve(), previously the pthread_atfork() child
	handler's call to Tcl_InitNotifier() would immediately recreate the
	notifier thread in the child after a fork.

	* macosx/tclMacOSXFCmd.c (TclMacOSXCopyFileAttributes):    add support
	* macosx/tclMacOSXNotify.c (Tcl_InitNotifier):             for weakly
	* unix/tclUnixInit.c (Tcl_GetEncodingNameFromEnvironment): importing
	symbols not available on OSX 10.2 or 10.3, enables binaires built on
	later OSX versions to run on earlier ones.
	* macosx/Tcl.xcodeproj/project.pbxproj: enable weak-linking; turn on
	                                        extra warnings.
	* macosx/README: document how to enable weak-linking; cleanup.
	* unix/tclUnixPort.h: add support for weak-linking; conditionalize
	AvailabilityMacros.h inclusion; only disable realpath on 10.2 or earlier
	when threads are enabled.
	* unix/tclLoadDyld.c (TclpLoadMemoryGetBuffer): change runtime Darwin
	* unix/tclUnixInit.c (TclpInitPlatform):        release check to use
	                                                global initialized once.
	* unix/tclUnixFCmd.c (DoRenameFile, TclpObjNormalizePath): add runtime
	Darwin release check to determine if realpath is threadsafe.
	* unix/configure.in: add check on Darwin for compiler support of weak
	* unix/tcl.m4:       import and for AvailabilityMacros.h header;
	move Darwin specific checks & defines that are only relevant to the tcl
	build out of tcl.m4; restrict framework option to Darwin; cleanup
	quoting and help messages.
	* unix/configure: autoconf-2.59
	* unix/tclConfig.h.in: autoheader-2.59

	* unix/tclLoadDyld.c (TclpLoadMemory): fix signed-with-unsigned
	comparison and other warnings from gcc4 -Wextra.

1 files changed, 81 insertions, 63 deletions

diff --git a/unix/tclUnixFCmd.c b/unix/tclUnixFCmd.c
index 1bba9ee..27b880e 100644
--- a/unix/tclUnixFCmd.c
+++ b/unix/tclUnixFCmd.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: tclUnixFCmd.c,v 1.53 2006/03/28 10:45:25 das Exp $
+ * RCS: @(#) $Id: tclUnixFCmd.c,v 1.54 2006/07/20 06:18:38 das Exp $
  *
  * Portions of this code were derived from NetBSD source code which has the
  * following copyright notice:
@@ -218,6 +218,22 @@ Realpath(
 #else
 #define Realpath realpath
 #endif
+
+#ifndef NO_REALPATH
+#if defined(__APPLE__) && defined(TCL_THREADS) && \
+	defined(MAC_OS_X_VERSION_MIN_REQUIRED) && \
+	MAC_OS_X_VERSION_MIN_REQUIRED < 1030
+/*
+ * prior to Darwin 7, realpath is not threadsafe, c.f. bug 711232;
+ * if we might potentially be running on pre-10.3 OSX,
+ * check Darwin release at runtime before using realpath.
+ */
+MODULE_SCOPE long tclMacOSXDarwinRelease;
+#define haveRealpath (tclMacOSXDarwinRelease >= 7)
+#else
+#define haveRealpath 1
+#endif
+#endif /* NO_REALPATH */
 
 /*
  *---------------------------------------------------------------------------
@@ -294,7 +310,7 @@ DoRenameFile(
      * compiled because realpath() not defined on all systems.
      */
 
-    if (errno == EINVAL) {
+    if (errno == EINVAL && haveRealpath) {
 	char srcPath[MAXPATHLEN], dstPath[MAXPATHLEN];
 	DIR *dirPtr;
 	Tcl_DirEntry *dirEntPtr;
@@ -1877,7 +1893,7 @@ TclpObjNormalizePath(
      * For speed, try to get the entire path in one go.
      */
 
-    if (nextCheckpoint == 0) {
+    if (nextCheckpoint == 0 && haveRealpath) {
 	char *lastDir = strrchr(currentPathEndPosition, '/');
 
 	if (lastDir != NULL) {
@@ -1950,86 +1966,88 @@ TclpObjNormalizePath(
      */
 
 #ifndef NO_REALPATH
-    /*
-     * If we only had '/foo' or '/' then we never increment nextCheckpoint and
-     * we don't need or want to go through 'Realpath'. Also, on some
-     * platforms, passing an empty string to 'Realpath' will give us the
-     * normalized pwd, which is not what we want at all!
-     */
+    if (haveRealpath) {
+	/*
+	 * If we only had '/foo' or '/' then we never increment nextCheckpoint
+	 * and we don't need or want to go through 'Realpath'. Also, on some
+	 * platforms, passing an empty string to 'Realpath' will give us the
+	 * normalized pwd, which is not what we want at all!
+	 */
 
-    if (nextCheckpoint == 0) {
-	return 0;
-    }
+	if (nextCheckpoint == 0) {
+	    return 0;
+	}
 
-    nativePath = Tcl_UtfToExternalDString(NULL, path, nextCheckpoint, &ds);
-    if (Realpath(nativePath, normPath) != NULL) {
-	int newNormLen;
+	nativePath = Tcl_UtfToExternalDString(NULL, path, nextCheckpoint, &ds);
+	if (Realpath(nativePath, normPath) != NULL) {
+	    int newNormLen;
 
-    wholeStringOk:
-	newNormLen = strlen(normPath);
-	if ((newNormLen == Tcl_DStringLength(&ds))
-		&& (strcmp(normPath, nativePath) == 0)) {
-	    /*
-	     * String is unchanged.
-	     */
+	wholeStringOk:
+	    newNormLen = strlen(normPath);
+	    if ((newNormLen == Tcl_DStringLength(&ds))
+		    && (strcmp(normPath, nativePath) == 0)) {
+		/*
+		 * String is unchanged.
+		 */
 
-	    Tcl_DStringFree(&ds);
+		Tcl_DStringFree(&ds);
 
-	    /*
-	     * Enable this to have the native FS claim normalization of the
-	     * whole path for existing files. That would permit the caller to
-	     * declare normalization complete without calls to additional
-	     * filesystems. Saving lots of calls is probably worth the extra
-	     * access() time here. When no other FS's are registered though,
-	     * things are less clear.
-	     *
-	    if (0 == access(normPath, F_OK)) {
-		return pathLen;
+		/*
+		 * Enable this to have the native FS claim normalization of the
+		 * whole path for existing files. That would permit the caller
+		 * to declare normalization complete without calls to additional
+		 * filesystems. Saving lots of calls is probably worth the extra
+		 * access() time here. When no other FS's are registered though,
+		 * things are less clear.
+		 *
+		if (0 == access(normPath, F_OK)) {
+		    return pathLen;
+		}
+		 */
+
+		return nextCheckpoint;
 	    }
+
+	    /*
+	     * Free up the native path and put in its place the converted,
+	     * normalized path.
 	     */
 
-	    return nextCheckpoint;
-	}
+	    Tcl_DStringFree(&ds);
+	    Tcl_ExternalToUtfDString(NULL, normPath, (int) newNormLen, &ds);
 
-	/*
-	 * Free up the native path and put in its place the converted,
-	 * normalized path.
-	 */
+	    if (path[nextCheckpoint] != '\0') {
+		/*
+		 * Not at end, append remaining path.
+		 */
 
-	Tcl_DStringFree(&ds);
-	Tcl_ExternalToUtfDString(NULL, normPath, (int) newNormLen, &ds);
+		int normLen = Tcl_DStringLength(&ds);
 
-	if (path[nextCheckpoint] != '\0') {
-	    /*
-	     * Not at end, append remaining path.
-	     */
+		Tcl_DStringAppend(&ds, path + nextCheckpoint,
+			pathLen - nextCheckpoint);
 
-	    int normLen = Tcl_DStringLength(&ds);
+		/*
+		 * We recognise up to and including the directory separator.
+		 */
 
-	    Tcl_DStringAppend(&ds, path + nextCheckpoint,
-		    pathLen - nextCheckpoint);
+		nextCheckpoint = normLen + 1;
+	    } else {
+		/*
+		 * We recognise the whole string.
+		 */
 
-	    /*
-	     * We recognise up to and including the directory separator.
-	     */
+		nextCheckpoint = Tcl_DStringLength(&ds);
+	    }
 
-	    nextCheckpoint = normLen + 1;
-	} else {
 	    /*
-	     * We recognise the whole string.
+	     * Overwrite with the normalized path.
 	     */
 
-	    nextCheckpoint = Tcl_DStringLength(&ds);
+	    Tcl_SetStringObj(pathPtr, Tcl_DStringValue(&ds),
+		    Tcl_DStringLength(&ds));
 	}
-
-	/*
-	 * Overwrite with the normalized path.
-	 */
-
-	Tcl_SetStringObj(pathPtr, Tcl_DStringValue(&ds),
-		Tcl_DStringLength(&ds));
+	Tcl_DStringFree(&ds);
     }
-    Tcl_DStringFree(&ds);
 #endif	/* !NO_REALPATH */
 
     return nextCheckpoint;