Re: [BUG] Unicode variables can be exported and are exported metafied

[Peter Stephenson <p.w.stephenson@xxxxxxxxxxxx>]

On Fri, 19 Dec 2014 19:17:37 +0100
"Christoph (Stucki) von Stuckrad" <stucki@xxxxxxxxxxxxxxx> wrote:
> On Thu, 18 Dec 2014, Bart Schaefer wrote:
> 
> > Are we sure it's even "legal" to export Unicode variable names?
> > Internally we can kinda ignore POSIX as we choose, but the
> > environment crosses those boundaries.
> 
> Independend of being 'legal' to me it seems dangerous!

Well, this seems to be controversial.  But it's not clear how useful such
variables are anyway.

This backs off yesterday's mess and ignores environment variable names
with characters with the top bit set.  We'll see if anyone trips over it.

pws

diff --git a/Src/params.c b/Src/params.c
index 1c51afd..b8e0c42 100644
--- a/Src/params.c
+++ b/Src/params.c
@@ -641,9 +641,17 @@ split_env_string(char *env, char **name, char **value)
     if (!env || !name || !value)
 	return 0;
 
-    tenv = metafy(env, strlen(env), META_HEAPDUP);
-    for (str = tenv; *str && *str != '='; str++)
-	;
+    tenv = strcpy(zhalloc(strlen(env) + 1), env);
+    for (str = tenv; *str && *str != '='; str++) {
+	if (STOUC(*str) >= 128) {
+	    /*
+	     * We'll ignore environment variables with names not
+	     * from the portable character set since we don't
+	     * know of a good reason to accept them.
+	     */
+	    return 0;
+	}
+    }
     if (str != tenv && *str == '=') {
 	*str = '\0';
 	*name = tenv;
@@ -4357,18 +4365,7 @@ arrfixenv(char *s, char **t)
 int
 zputenv(char *str)
 {
-    char *ptr;
     DPUTS(!str, "Attempt to put null string into environment.");
-    /*
-     * The environment uses NULL-terminated strings, so just
-     * unmetafy and ignore the length.
-     */
-    for (ptr = str; *ptr && *ptr != Meta; ptr++)
-	;
-    if (*ptr == Meta) {
-	str = dupstring(str);
-	unmetafy(str, NULL);
-    }
 #ifdef USE_SET_UNSET_ENV
     /*
      * If we are using unsetenv() to remove values from the
@@ -4377,11 +4374,21 @@ zputenv(char *str)
      * Unfortunately this is a slightly different interface
      * from what zputenv() assumes.
      */
+    char *ptr;
     int ret;
 
-    for (ptr = str; *ptr && *ptr != '='; ptr++)
+    for (ptr = str; *ptr && STOUC(*ptr) < 128 && *ptr != '='; ptr++)
 	;
-    if (*ptr) {
+    if (STOUC(*ptr) >= 128) {
+	/*
+	 * Environment variables not in the portable character
+	 * set are non-standard and we don't really know of
+	 * a use for them.
+	 *
+	 * We'll disable until someone complains.
+	 */
+	return 1;
+    } else if (*ptr) {
 	*ptr = '\0';
 	ret = setenv(str, ptr+1, 1);
 	*ptr = '=';