hush: fix a nommu bug where a part of function body is lost if run in a pipe

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

3 files changed, 42 insertions, 10 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 3ca04494c..752080a64 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -3161,11 +3161,29 @@ static int reserved_word(o_string *word, struct parse_context *ctx)
                 old->command->group = ctx->list_head;
                 old->command->cmd_type = CMD_NORMAL;
 # if !BB_MMU
-                o_addstr(&old->as_string, ctx->as_string.data);
-                o_free_unsafe(&ctx->as_string);
-                old->command->group_as_string = xstrdup(old->as_string.data);
-                debug_printf_parse("pop, remembering as:'%s'\n",
-                                old->command->group_as_string);
+                /* At this point, the compound command's string is in
+                 * ctx->as_string... except for the leading keyword!
+                 * Consider this example: "echo a | if true; then echo a; fi"
+                 * ctx->as_string will contain "true; then echo a; fi",
+                 * with "if " remaining in old->as_string!
+                 */
+                {
+                        char *str;
+                        int len = old->as_string.length;
+                        /* Concatenate halves */
+                        o_addstr(&old->as_string, ctx->as_string.data);
+                        o_free_unsafe(&ctx->as_string);
+                        /* Find where leading keyword starts in first half */
+                        str = old->as_string.data + len;
+                        if (str > old->as_string.data)
+                                str--; /* skip whitespace after keyword */
+                        while (str > old->as_string.data && isalpha(str[-1]))
+                                str--;
+                        /* Ugh, we're done with this horrid hack */
+                        old->command->group_as_string = xstrdup(str);
+                        debug_printf_parse("pop, remembering as:'%s'\n",
+                                        old->command->group_as_string);
+                }
 # endif
                 *ctx = *old;   /* physical copy */
                 free(old);
@@ -4248,7 +4266,7 @@ static struct pipe *parse_stream(char **pstring,
                                 pi = NULL;
                         }
 #if !BB_MMU
-                        debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
+                        debug_printf_parse("as_string1 '%s'\n", ctx.as_string.data);
                         if (pstring)
                                 *pstring = ctx.as_string.data;
                         else
@@ -4399,7 +4417,7 @@ static struct pipe *parse_stream(char **pstring,
                         ) {
                                 o_free(&dest);
 #if !BB_MMU
-                                debug_printf_parse("as_string '%s'\n", ctx.as_string.data);
+                                debug_printf_parse("as_string2 '%s'\n", ctx.as_string.data);
                                 if (pstring)
                                         *pstring = ctx.as_string.data;
                                 else
@@ -4639,9 +4657,6 @@ static struct pipe *parse_stream(char **pstring,
                                  * with redirect_opt_num(), but bash doesn't do it.
                                  * "echo foo 2| cat" yields "foo 2". */
                                 done_command(&ctx);
-#if !BB_MMU
-                                o_reset_to_empty_unquoted(&ctx.as_string);
-#endif
                         }
                         goto new_cmd;
                 case '(':
diff --git a/shell/hush_test/hush-misc/nommu3.right b/shell/hush_test/hush-misc/nommu3.right
new file mode 100644
index 000000000..da1534bef
--- /dev/null
+++ b/shell/hush_test/hush-misc/nommu3.right
@@ -0,0 +1,2 @@
+Ok
+0
diff --git a/shell/hush_test/hush-misc/nommu3.tests b/shell/hush_test/hush-misc/nommu3.tests
new file mode 100755
index 000000000..0aca67a67
--- /dev/null
+++ b/shell/hush_test/hush-misc/nommu3.tests
@@ -0,0 +1,15 @@
+#!/bin/sh
+
+func()
+{
+        while read p; do echo "$p"; done
+}
+
+pipe_to_func()
+{
+        # We had a NOMMU bug which caused "echo Ok |" part ot be lost
+        echo Ok | func
+}
+
+pipe_to_func | cat
+echo $?