Do not export variables with dot names (re: 8e72608c)

Variables with a dot in their name, such as those declared in
namespace { ... } blocks, are usually stored in a separate tree
with their actual names not containing any dots. But under some
circumstances, including at least direct assignment of a
non-preexisting dot variable, dot variables are stored in the main
sh.var_tree with names actually containing dots. With allexport
active, those could end up exported to the environment. This bug
was also present in previous release versions of ksh.

src/cmd/ksh93/sh/name.c: pushnam():
- Check for a dot in the name before pushing a variable to export.

src/cmd/ksh93/data/builtins.c

@@ -169,7 +169,7 @@ const struct shtable3 shtab_builtins[] =
 
 const char sh_set[] =
 "[a?All variables that are assigned a value while this option is on are "
-	"automatically exported.]"
+	"automatically exported, unless they have a dot in their name.]"
 "[b?The shell writes a message to standard error as soon it detects that "
 	"a background job completes rather than waiting until the next prompt.]"
 "[e?A simple command that has an non-zero exit status will cause the shell "

src/cmd/ksh93/include/version.h

@@ -21,7 +21,7 @@
 
 #define SH_RELEASE_FORK	"93u+m"		/* only change if you develop a new ksh93 fork */
 #define SH_RELEASE_SVER	"1.0.0-beta.2"	/* semantic version number: https://semver.org */
-#define SH_RELEASE_DATE	"2022-02-04"	/* must be in this format for $((.sh.version)) */
+#define SH_RELEASE_DATE	"2022-02-05"	/* must be in this format for $((.sh.version)) */
 #define SH_RELEASE_CPYR	"(c) 2020-2022 Contributors to ksh " SH_RELEASE_FORK
 
 /* Scripts sometimes field-split ${.sh.version}, so don't change amount of whitespace. */

src/cmd/ksh93/sh.1

@@ -7388,7 +7388,12 @@ See \f2History Expansion\fP above.
 .TP 8
 .B \-a
 All variables that are assigned a value while this option is on
-are automatically exported.
+are automatically exported, unless they have a dot in their name.
+Variables created in namespaces declared with the
+.B namespace
+keyword (see
+.I Name Spaces
+above) are only exported while their name space is active.
 .TP 8
 .B \-b
 Prints job completion messages as soon as a background job changes

src/cmd/ksh93/sh/name.c

@@ -2197,10 +2197,15 @@ static void attstore(register Namval_t *np, void *data)
 	ap->attval = strcopy(++ap->attval,nv_name(np));
 }
 
+/*
+ * Called from sh_envgen() to push an individual variable to export
+ */
 static void pushnam(Namval_t *np, void *data)
 {
 	register char *value;
 	register struct adata *ap = (struct adata*)data;
+	if(strchr(np->nvname,'.'))
+		return;
 	ap->tp = 0;
 	if(nv_isattr(np,NV_IMPORT) && np->nvenv)
 		*ap->argnam++ = np->nvenv;
@@ -2213,7 +2218,6 @@ static void pushnam(Namval_t *np, void *data)
 /*
  * Generate the environment list for the child.
  */
-
 char **sh_envgen(void)
 {
 	register char **er;

src/cmd/ksh93/tests/attributes.sh

@@ -728,6 +728,13 @@ exp='typeset -x bar=2'
 got=$(typeset -p bar)
 [[ $got == "$exp" ]] || err_exit 'Variable ${bar} should be exported' \
 	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
+.foo=
+.foo.bar=baz
+exp=''
+got=$(env | grep '^\.foo[.=]')
+[[ $got == "$exp" ]] || err_exit 'Variables with dots in name exported' \
+	"(expected $(printf %q "$exp"), got $(printf %q "$got"))"
+unset .foo.bar .foo
 set +o allexport
 
 # ======