From c4ada7934307c6ef0b5b207df13a54fecd4ad81d Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Wed, 15 Apr 2009 23:29:00 +0000 Subject: [PATCH] hush: remove old disabled ^Z handling --- shell/hush.c | 75 +++++----------------------------------------------- 1 file changed, 7 insertions(+), 68 deletions(-) diff --git a/shell/hush.c b/shell/hush.c index 1753be0d1..16f304d81 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -56,7 +56,6 @@ * figure out what to do with backslash-newline * continuation lines, both explicit and implicit - done? * SIGHUP handling - * ^Z handling (and explain it in comments for mere humans) * separate job control from interactiveness * (testcase: booting with init=/bin/hush does not show prompt (2009-04)) * @@ -432,7 +431,6 @@ struct globals { int last_jobid; struct pipe *job_list; struct pipe *toplevel_list; -//// smallint ctrl_z_flag; #endif smallint flag_SIGINT; #if ENABLE_HUSH_LOOPS @@ -474,12 +472,6 @@ struct globals { int debug_indent; #endif char user_input_buf[ENABLE_FEATURE_EDITING ? BUFSIZ : 2]; -#if ENABLE_FEATURE_SH_STANDALONE - struct nofork_save_area nofork_save; -#endif -#if ENABLE_HUSH_JOB - sigjmp_buf toplevel_jb; -#endif }; #define G (*ptr_to_globals) /* Not #defining name to G.name - this quickly gets unwieldy @@ -977,13 +969,14 @@ static void free_strings(char **strings) * SIGHUP (interactive): * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit * SIGTTIN, SIGTTOU, SIGTSTP (if job control is on): ignore - * (note that ^Z is handled not by trapping SIGTSTP, but by seeing - * that all pipe members are stopped) (right?) + * Note that ^Z is handled not by trapping SIGTSTP, but by seeing + * that all pipe members are stopped. Try this in bash: + * while :; do :; done - ^Z does not background it + * (while :; do :; done) - ^Z backgrounds it * SIGINT (interactive): wait for last pipe, ignore the rest * of the command line, show prompt. NB: ^C does not send SIGINT * to interactive shell while shell is waiting for a pipe, * since shell is bg'ed (is not in foreground process group). - * (check/expand this) * Example 1: this waits 5 sec, but does not execute ls: * "echo $$; sleep 5; ls -l" + "kill -INT " * Example 2: this does not wait and does not execute ls: @@ -3411,12 +3404,11 @@ static int run_pipe(struct pipe *pi) if (i >= 0 && APPLET_IS_NOFORK(i)) { rcode = setup_redirects(command, squirrel); if (rcode == 0) { - save_nofork_data(&G.nofork_save); new_env = expand_assignments(argv, command->assignment_cnt); old_env = putenv_all_and_save_old(new_env); debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", argv_expanded[0], argv_expanded[1]); - rcode = run_nofork_applet_prime(&G.nofork_save, i, argv_expanded); + rcode = run_nofork_applet(i, argv_expanded); } goto clean_up_and_ret; } @@ -3643,7 +3635,7 @@ static int run_list(struct pipe *pi) smallint last_rword; /* ditto */ #endif - debug_printf_exec("run_list start lvl %d\n", G.run_list_level + 1); + debug_printf_exec("run_list start lvl %d\n", G.run_list_level); debug_enter(); #if ENABLE_HUSH_LOOPS @@ -3677,51 +3669,9 @@ static int run_list(struct pipe *pi) * in order to return, no direct "return" statements please. * This helps to ensure that no memory is leaked. */ -////TODO: ctrl-Z handling needs re-thinking and re-testing - #if ENABLE_HUSH_JOB - /* Example of nested list: "while true; do { sleep 1 | exit 2; } done". - * We are saving state before entering outermost list ("while...done") - * so that ctrl-Z will correctly background _entire_ outermost list, - * not just a part of it (like "sleep 1 | exit 2") */ - if (++G.run_list_level == 1 && G_interactive_fd) { - if (sigsetjmp(G.toplevel_jb, 1)) { - /* ctrl-Z forked and we are parent; or ctrl-C. - * Sighandler has longjmped us here */ - signal(SIGINT, SIG_IGN); - signal(SIGTSTP, SIG_IGN); - /* Restore level (we can be coming from deep inside - * nested levels) */ - G.run_list_level = 1; -#if ENABLE_FEATURE_SH_STANDALONE - if (G.nofork_save.saved) { /* if save area is valid */ - debug_printf_jobs("exiting nofork early\n"); - restore_nofork_data(&G.nofork_save); - } + G.run_list_level++; #endif -//// if (G.ctrl_z_flag) { -//// /* ctrl-Z has forked and stored pid of the child in pi->pid. -//// * Remember this child as background job */ -//// insert_bg_job(pi); -//// } else { - /* ctrl-C. We just stop doing whatever we were doing */ - bb_putchar('\n'); -//// } - USE_HUSH_LOOPS(loop_top = NULL;) - USE_HUSH_LOOPS(G.depth_of_loop = 0;) - rcode = 0; - goto ret; - } -//// /* ctrl-Z handler will store pid etc in pi */ -//// G.toplevel_list = pi; -//// G.ctrl_z_flag = 0; -#if ENABLE_FEATURE_SH_STANDALONE - G.nofork_save.saved = 0; /* in case we will run a nofork later */ -#endif -//// signal_SA_RESTART_empty_mask(SIGTSTP, handler_ctrl_z); -//// signal(SIGINT, handler_ctrl_c); - } -#endif /* JOB */ #if HAS_KEYWORDS rword = RES_NONE; @@ -3967,18 +3917,7 @@ static int run_list(struct pipe *pi) } /* for (pi) */ #if ENABLE_HUSH_JOB -//// if (G.ctrl_z_flag) { -//// /* ctrl-Z forked somewhere in the past, we are the child, -//// * and now we completed running the list. Exit. */ -//////TODO: _exit? -//// exit(rcode); -//// } - ret: G.run_list_level--; -//// if (!G.run_list_level && G_interactive_fd) { -//// signal(SIGTSTP, SIG_IGN); -//// signal(SIGINT, SIG_IGN); -//// } #endif #if ENABLE_HUSH_LOOPS if (loop_top)