hush: fix comment parsing in `cmd`, closes 10421

function                                             old     new   delta
parse_stream                                        2692    2690      -2

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

1 files changed, 13 insertions, 4 deletions

diff --git a/shell/hush.c b/shell/hush.c
index d27550ba0..708555ac4 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -5140,14 +5140,23 @@ static struct pipe *parse_stream(char **pstring,
                 case '#':
                         if (dest.length == 0 && !dest.has_quoted_part) {
                                 /* skip "#comment" */
+                                /* note: we do not add it to &ctx.as_string */
+/* TODO: in bash:
+ * comment inside $() goes to the next \n, even inside quoted string (!):
+ * cmd "$(cmd2 #comment)" - syntax error
+ * cmd "`cmd2 #comment`" - ok
+ * We accept both (comment ends where command subst ends, in both cases).
+ */
                                 while (1) {
                                         ch = i_peek(input);
-                                        if (ch == EOF || ch == '\n')
+                                        if (ch == '\n') {
+                                                nommu_addchr(&ctx.as_string, '\n');
+                                                break;
+                                        }
+                                        ch = i_getch(input);
+                                        if (ch == EOF)
                                                 break;
-                                        i_getch(input);
-                                        /* note: we do not add it to &ctx.as_string */
                                 }
-                                nommu_addchr(&ctx.as_string, '\n');
                                 continue; /* back to top of while (1) */
                         }
                         break;