3 files changed, 61 insertions, 28 deletions

diff --git a/hush.c b/hush.c
index 126f9da89..3b1e53c82 100644
--- a/hush.c
+++ b/hush.c
@@ -1326,19 +1326,18 @@ static int run_pipe_real(struct pipe *pi)
          * Builtins within pipes have to fork anyway, and are handled in
          * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
          */
-        if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
-                child = & (pi->progs[0]);
-                if (child->group && ! child->subshell) {
-                        int squirrel[] = {-1, -1, -1};
-                        int rcode;
-                        debug_printf("non-subshell grouping\n");
-                        setup_redirects(child, squirrel);
-                        /* XXX could we merge code with following builtin case,
-                         * by creating a pseudo builtin that calls run_list_real? */
-                        rcode = run_list_real(child->group);
-                        restore_redirects(squirrel);
-                        return rcode;
-                }
+        if (pi->num_progs == 1) child = & (pi->progs[0]);
+        if (pi->num_progs == 1 && child->group && child->subshell == 0) {
+                int squirrel[] = {-1, -1, -1};
+                int rcode;
+                debug_printf("non-subshell grouping\n");
+                setup_redirects(child, squirrel);
+                /* XXX could we merge code with following builtin case,
+                 * by creating a pseudo builtin that calls run_list_real? */
+                rcode = run_list_real(child->group);
+                restore_redirects(squirrel);
+                return rcode;
+        } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
                 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
                 if (i!=0 && child->argv[i]==NULL) {
                         /* assignments, but no command: set the local environment */
@@ -1352,7 +1351,8 @@ static int run_pipe_real(struct pipe *pi)
                                  * variable. */
                                 int export_me=0;
                                 char *name, *value;
-                                name = strdup(child->argv[i]);
+                                name = xstrdup(child->argv[i]);
+                                debug_printf("Local environment set: %s\n", name);
                                 value = strchr(name, '=');
                                 if (value)
                                         *value=0;
@@ -1478,6 +1478,7 @@ static int run_list_real(struct pipe *pi)
                 if (rmode == RES_ELIF && !if_code) continue;
                 if (pi->num_progs == 0) continue;
                 rcode = run_pipe_real(pi);
+                debug_printf("run_pipe_real returned %d\n",rcode);
                 if (rcode!=-1) {
                         /* We only ran a builtin: rcode was set by the return value
                          * of run_pipe_real(), and we don't need to wait for anything. */
@@ -1943,6 +1944,7 @@ int reserved_word(o_string *dest, struct p_context *ctx)
                                 debug_printf("pop stack\n");
                                 old = ctx->stack;
                                 old->child->group = ctx->list_head;
+                                old->child->subshell = 0;
                                 *ctx = *old;   /* physical copy */
                                 free(old);
                         }
diff --git a/shell/hush.c b/shell/hush.c
index 126f9da89..3b1e53c82 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -1326,19 +1326,18 @@ static int run_pipe_real(struct pipe *pi)
          * Builtins within pipes have to fork anyway, and are handled in
          * pseudo_exec.  "echo foo | read bar" doesn't work on bash, either.
          */
-        if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
-                child = & (pi->progs[0]);
-                if (child->group && ! child->subshell) {
-                        int squirrel[] = {-1, -1, -1};
-                        int rcode;
-                        debug_printf("non-subshell grouping\n");
-                        setup_redirects(child, squirrel);
-                        /* XXX could we merge code with following builtin case,
-                         * by creating a pseudo builtin that calls run_list_real? */
-                        rcode = run_list_real(child->group);
-                        restore_redirects(squirrel);
-                        return rcode;
-                }
+        if (pi->num_progs == 1) child = & (pi->progs[0]);
+        if (pi->num_progs == 1 && child->group && child->subshell == 0) {
+                int squirrel[] = {-1, -1, -1};
+                int rcode;
+                debug_printf("non-subshell grouping\n");
+                setup_redirects(child, squirrel);
+                /* XXX could we merge code with following builtin case,
+                 * by creating a pseudo builtin that calls run_list_real? */
+                rcode = run_list_real(child->group);
+                restore_redirects(squirrel);
+                return rcode;
+        } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
                 for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ }
                 if (i!=0 && child->argv[i]==NULL) {
                         /* assignments, but no command: set the local environment */
@@ -1352,7 +1351,8 @@ static int run_pipe_real(struct pipe *pi)
                                  * variable. */
                                 int export_me=0;
                                 char *name, *value;
-                                name = strdup(child->argv[i]);
+                                name = xstrdup(child->argv[i]);
+                                debug_printf("Local environment set: %s\n", name);
                                 value = strchr(name, '=');
                                 if (value)
                                         *value=0;
@@ -1478,6 +1478,7 @@ static int run_list_real(struct pipe *pi)
                 if (rmode == RES_ELIF && !if_code) continue;
                 if (pi->num_progs == 0) continue;
                 rcode = run_pipe_real(pi);
+                debug_printf("run_pipe_real returned %d\n",rcode);
                 if (rcode!=-1) {
                         /* We only ran a builtin: rcode was set by the return value
                          * of run_pipe_real(), and we don't need to wait for anything. */
@@ -1943,6 +1944,7 @@ int reserved_word(o_string *dest, struct p_context *ctx)
                                 debug_printf("pop stack\n");
                                 old = ctx->stack;
                                 old->child->group = ctx->list_head;
+                                old->child->subshell = 0;
                                 *ctx = *old;   /* physical copy */
                                 free(old);
                         }
diff --git a/tests/sh.testcases b/tests/sh.testcases
index 88e709f87..e2a75873e 100644
--- a/tests/sh.testcases
+++ b/tests/sh.testcases
@@ -28,6 +28,35 @@ if false; then tr 'A-Z' 'a-z'; else echo bar4; fi <foo
 if true || false; then echo foo; else echo bar5; fi
 if true && false; then echo bar6; else echo foo; fi
 
+# basic distinction between local and env variables
+unset FOO
+FOO=bar env | grep FOO
+echo "but not here: $FOO"
+FOO=bar
+env | grep FOO
+echo "yes, here: $FOO"
+FOO=
+echo a $FOO b
+echo "a $FOO b"
+
+# not quite so basic variables.  Credit to Matt Kraai.
+unset FOO
+FOO=bar
+export FOO
+env | grep FOO
+unset FOO
+export FOO=bar
+FOO=baz
+env | grep FOO
+
+# interaction between environment variables and if/then and subshells
+FOO=default
+if true; then FOO=new; fi
+echo $FOO
+FOO=default
+(FOO=bogus)
+echo $FOO
+
 # make sure we can duplicate file descriptors properly
 echo replacement >foo 2>&1
 cat foo