hush: fix break'ing out of {} and () groups; with testcase

function                                             old     new   delta
builtin_break                                         93     129     +36
builtin_continue                                      21      47     +26
run_list                                            1973    1976      +3

diff --git a/shell/hush.c b/shell/hush.c
index 8ffc6121a48a6e90b3100eb8b56f4ce049e482ca..eb70c9d9f4065cb51f6a105e4888e22b7a987853 100644 (file)
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -446,6 +446,7 @@ struct globals {
        int global_argc;
 #if ENABLE_HUSH_LOOPS
        unsigned depth_break_continue;
+       unsigned depth_of_loop;
 #endif
        pid_t last_bg_pid;
        const char *ifs;
@@ -496,6 +497,7 @@ enum { run_list_level = 0 };
 #define ifs              (G.ifs             )
 #define flag_break_continue  (G.flag_break_continue )
 #define depth_break_continue (G.depth_break_continue)
+#define depth_of_loop    (G.depth_of_loop   )
 #define fake_mode        (G.fake_mode       )
 #define cwd              (G.cwd             )
 #define last_bg_pid      (G.last_bg_pid     )
@@ -2153,13 +2155,14 @@ static int run_list(struct pipe *pi)
                if (rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR) {
                        /* start of a loop: remember where loop starts */
                        loop_top = pi;
+                       depth_of_loop++;
                }
 #endif
                if (rword == skip_more_for_this_rword && flag_skip) {
-                       /* it is "<false> && CMD" or "<true> || CMD"
-                        * and we should not execute CMD */
                        if (pi->followup == PIPE_SEQ)
                                flag_skip = 0;
+                       /* it is "<false> && CMD" or "<true> || CMD"
+                        * and we should not execute CMD */
                        continue;
                }
                flag_skip = 1;
@@ -2277,15 +2280,13 @@ static int run_list(struct pipe *pi)
                                                depth_break_continue--;
                                                if (depth_break_continue == 0)
                                                        flag_break_continue = 0;
-                                               if (depth_break_continue != 0 || fbc == BC_BREAK)
-                                                       goto check_jobs_and_break;
-                                               /* "continue": simulate end of loop */
-                                               rword = RES_DONE;
-                                               continue;
-                                       }               
-                                       flag_break_continue = 0;
-                                       bb_error_msg("break/continue: only meaningful in a loop");
-                                       /* bash compat: exit code is still 0 */
+                                               /* else: e.g. "continue 2" should *break* once, *then* continue */
+                                       } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */
+                                       if (depth_break_continue != 0 || fbc == BC_BREAK)
+                                               goto check_jobs_and_break;
+                                       /* "continue": simulate end of loop */
+                                       rword = RES_DONE;
+                                       continue;
                                }
 #endif
                        } else if (pi->followup == PIPE_BG) {
@@ -2358,6 +2359,8 @@ static int run_list(struct pipe *pi)
 #endif
        debug_printf_exec("run_list lvl %d return %d\n", run_list_level + 1, rcode);
 #if ENABLE_HUSH_LOOPS
+       if (loop_top)
+               depth_of_loop--;
        free(for_list);
 #endif
 #if ENABLE_HUSH_CASE
@@ -4554,6 +4557,10 @@ static int builtin_unset(char **argv)
 #if ENABLE_HUSH_LOOPS
 static int builtin_break(char **argv)
 {
+       if (depth_of_loop == 0) {
+               bb_error_msg("%s: only meaningful in a loop", "break");
+               return EXIT_SUCCESS; /* bash compat */
+       }
        flag_break_continue++; /* BC_BREAK = 1 */
        depth_break_continue = 1;
        if (argv[1]) {
@@ -4564,12 +4571,18 @@ static int builtin_break(char **argv)
                        depth_break_continue = UINT_MAX;
                }
        }
+       if (depth_of_loop > depth_break_continue)
+               depth_break_continue = depth_of_loop;
        return EXIT_SUCCESS;
 }
 
 static int builtin_continue(char **argv)
 {
-       flag_break_continue++; /* BC_CONTINUE = 2 = 1+1 */
-       return builtin_break(argv);
+       if (depth_of_loop) {
+               flag_break_continue++; /* BC_CONTINUE = 2 = 1+1 */
+               return builtin_break(argv);
+       }
+       bb_error_msg("%s: only meaningful in a loop", "continue");
+       return EXIT_SUCCESS; /* bash compat */
 }
 #endif

diff --git a/shell/hush_test/hush-misc/break5.right b/shell/hush_test/hush-misc/break5.right
new file mode 100644 (file)
index 0000000..0b9df2a
--- /dev/null
+++ b/shell/hush_test/hush-misc/break5.right
@@ -0,0 +1,13 @@
+A
+B
+0
+A:a
+B
+D
+A:b
+B
+D
+A:c
+B
+D
+0

diff --git a/shell/hush_test/hush-misc/break5.tests b/shell/hush_test/hush-misc/break5.tests
new file mode 100755 (executable)
index 0000000..273e040
--- /dev/null
+++ b/shell/hush_test/hush-misc/break5.tests
@@ -0,0 +1,4 @@
+while true; do echo A; { echo B; break; echo C; }; echo D; done
+echo $?
+for v in a b c; do echo A:$v; (echo B; break; echo C); echo D; done
+echo $?