hush: fix "for a in; do echo 'I should never run'; done" bug

3 files changed, 10 insertions, 8 deletions

diff --git a/shell/hush.c b/shell/hush.c
index ae12ebec4..45448c5f3 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -2004,7 +2004,7 @@ static int run_list(struct pipe *pi)
                  || (rpipe->res_word == RES_FOR && rpipe->next->res_word != RES_IN)
                 ) {
                         /* TODO: what is tested in the first condition? */
-                        syntax("malformed for"); /* 2nd condition: not followed by IN */
+                        syntax("malformed for"); /* 2nd condition: FOR not followed by IN */
                         debug_printf_exec("run_list lvl %d return 1\n", run_list_level);
                         return 1;
                 }
@@ -2898,7 +2898,8 @@ static int done_word(o_string *word, struct p_context *ctx)
                 ctx->pending_redirect = NULL;
         }
 #if ENABLE_HUSH_LOOPS
-        if (ctx->res_w == RES_FOR) { /* comment? */
+        /* comment? is it forcing "for" to have just one word (variable name)? */
+        if (ctx->res_w == RES_FOR) {
 //TESTING
 //looks like (word->length == 0 && !word->nonnull) is true here, always
 //(due to o_reset). done_word would return at once. Why then?
@@ -2910,8 +2911,8 @@ static int done_word(o_string *word, struct p_context *ctx)
         return 0;
 }
 
-/* The only possible error here is out of memory, in which case
- * xmalloc exits. */
+/* Command (member of a pipe) is complete. The only possible error here
+ * is out of memory, in which case xmalloc exits. */
 static int done_command(struct p_context *ctx)
 {
         /* The child is really already in the pipe structure, so
@@ -2949,7 +2950,6 @@ static int done_command(struct p_context *ctx)
 
 static void done_pipe(struct p_context *ctx, pipe_style type)
 {
-        struct pipe *new_p;
         int not_null;
 
         debug_printf_parse("done_pipe entered, followup %d\n", type);
@@ -2960,9 +2960,11 @@ static void done_pipe(struct p_context *ctx, pipe_style type)
         ctx->ctx_inverted = 0;
         /* Without this check, even just <enter> on command line generates
          * tree of three NOPs (!). Which is harmless but annoying.
-         * IOW: it is safe to do it unconditionally. */
-        if (not_null) {
-                new_p = new_pipe();
+         * IOW: it is safe to do it unconditionally.
+         * RES_IN case is for "for a in; do ..." (empty IN set)
+         * to work. */
+        if (not_null || ctx->pipe->res_word == RES_IN) {
+                struct pipe *new_p = new_pipe();
                 ctx->pipe->next = new_p;
                 ctx->pipe = new_p;
                 ctx->child = NULL; /* needed! */
diff --git a/shell/hush_test/hush-bugs/empty_for.right b/shell/hush_test/hush-misc/empty_for.right
index 290d39b7e..290d39b7e 100644
--- a/shell/hush_test/hush-bugs/empty_for.right
+++ b/shell/hush_test/hush-misc/empty_for.right
diff --git a/shell/hush_test/hush-bugs/empty_for.tests b/shell/hush_test/hush-misc/empty_for.tests
index 0cb52e849..0cb52e849 100755
--- a/shell/hush_test/hush-bugs/empty_for.tests
+++ b/shell/hush_test/hush-misc/empty_for.tests