Backout [477949] for Tk 8.5, after discussion in TclCore mailing list: option readfile cannot use multibytes. Ticket [0a3d799a]

To clarify a bit, what we discovered was that [[option readfile]]
as found in all Tk releases up to and including 8.5.18 is already
able to read in the whole BMP, so long as the file is stored in
the encoding utf-8.  The classic ASCII subset is fine.  utf-8 is fine.
Other encodings are at best non-portable.

What [477949] did was to add support for files stored in
[[encoding system]] but at the expense of breaking the
support for the files stored in utf-8.  Not the right outcome
for a patch release.

1 files changed, 2 insertions, 11 deletions

diff --git a/generic/tkOption.c b/generic/tkOption.c
index 17989f8..95b140d 100644
--- a/generic/tkOption.c
+++ b/generic/tkOption.c
@@ -1086,7 +1086,7 @@ ReadOptionFile(
     char *buffer;
     int result, bufferSize;
     Tcl_Channel chan;
-    Tcl_DString newName, optString;
+    Tcl_DString newName;
 
     /*
      * Prevent file system access in a safe interpreter.
@@ -1136,16 +1136,7 @@ ReadOptionFile(
     }
     Tcl_Close(NULL, chan);
     buffer[bufferSize] = 0;
-    if ((bufferSize>2) && !memcmp(buffer, "\357\273\277", 3)) {
-	/* File starts with UTF-8 BOM */
-	result = AddFromString(interp, tkwin, buffer+3, priority);
-    } else {
-	Tcl_DStringInit(&optString);
-	Tcl_ExternalToUtfDString(NULL, buffer, bufferSize, &optString);
-	result = AddFromString(interp, tkwin, Tcl_DStringValue(&optString),
-		priority);
-	Tcl_DStringFree(&optString);
-    }
+    result = AddFromString(interp, tkwin, buffer, priority);
     ckfree(buffer);
     return result;
 }