diff options
| -rw-r--r-- | coreutils/sleep.c | 2 | ||||
| -rw-r--r-- | shell/hush.c | 95 |
2 files changed, 84 insertions, 13 deletions
diff --git a/coreutils/sleep.c b/coreutils/sleep.c index 592005bab..b758de33b 100644 --- a/coreutils/sleep.c +++ b/coreutils/sleep.c @@ -61,6 +61,8 @@ int sleep_main(int argc, char **argv) #endif /* FEATURE_FANCY_SLEEP */ if (sleep(duration)) { +//for hush debugging: +sleep(1); bb_perror_nomsg_and_die(); } diff --git a/shell/hush.c b/shell/hush.c index e2ce3676d..c87f3b566 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -431,6 +431,56 @@ static const struct built_in_command bltins[] = { { NULL, NULL, NULL } }; +/* move to libbb? */ +static void signal_SA_RESTART(int sig, void (*handler)(int)) +{ + struct sigaction sa; + sa.sa_handler = handler; + sa.sa_flags = SA_RESTART; + sigemptyset(&sa.sa_mask); + sigaction(sig, &sa, NULL); +} + +static sigjmp_buf nofork_jb; +static smallint nofork_flag; +static struct pipe *nofork_pipe; + +static void handler_ctrl_z(int sig) +{ + pid_t pid; + + fprintf(stderr, "got tty sig %d\n", sig); + if (!nofork_flag) + return; + pid = fork(); + if (pid < 0) /* can't fork. Pretend there were no Ctrl-Z */ + return; + fprintf(stderr, "bg'ing nofork\n"); + nofork_flag = 0; + nofork_pipe->running_progs = 1; + nofork_pipe->stopped_progs = 0; + if (!pid) { /* child */ + fprintf(stderr, "setting pgrp for child\n"); + setpgrp(); + signal(sig, SIG_DFL); /* make child do default action (stop) */ + raise(sig); /* resend TSTP so that child will be stopped */ + fprintf(stderr, "returning to child\n"); + /* return to nofork, it will eventually exit now, + * not return back to shell */ + return; + } + /* parent */ + /* finish filling up pipe info */ + nofork_pipe->pgrp = pid; /* child is in its own pgrp */ + nofork_pipe->progs[0].pid = pid; + nofork_pipe->running_progs = 1; + nofork_pipe->stopped_progs = 0; + /* parent needs to longjmp out of running nofork. + * we will "return" exitcode 0, with child put in background */ +// as usual we can have all kinds of nasty problems with leaked malloc data here + siglongjmp(nofork_jb, 1); +} + /* Restores tty foreground process group, and exits. * May be called as signal handler for fatal signal * (will faithfully resend signal to itself, producing correct exit state) @@ -1535,14 +1585,32 @@ static int run_pipe_real(struct pipe *pi) } #if ENABLE_FEATURE_SH_STANDALONE { -// FIXME: applet runs like part of shell - for example, it ignores -// SIGINT! Try to Ctrl-C out of "rm -i"... doesn't work const struct bb_applet *a = find_applet_by_name(argv[i]); if (a && a->nofork) { setup_redirects(child, squirrel); - rcode = run_nofork_applet(a, argv + i); - restore_redirects(squirrel); - return rcode; + if (sigsetjmp(nofork_jb, 1) == 0) { +// enable ctrl_z here, not globally? + nofork_flag = 1; + /* TSTP handler will store pid there etc */ + nofork_pipe = pi; + rcode = run_nofork_applet(a, argv + i); + if (--nofork_flag != 0) + /* Ctrl-Z! forked, we are child */ + exit(rcode); + restore_redirects(squirrel); + return rcode; + } else { + fprintf(stderr, "Exiting nofork early\n"); + /* Ctrl-Z, forked, we are parent. + * Sighandler has longjmped us here */ +//problem: run_nofork_applet did not do the +// "restore" trick and globals are trashed: +// for one, applet_name is not "hush" :) +// need to split run_nofork_applet into setup/run/restore... + restore_redirects(squirrel); + insert_bg_job(pi); + return 0; + } } } #endif @@ -1585,7 +1653,7 @@ static int run_pipe_real(struct pipe *pi) /* Don't do pgrp restore anymore on fatal signals */ set_fatal_sighandler(SIG_DFL); } - + // in non-interactive case fatal sigs are already SIG_DFL close_all(); if (nextin != 0) { dup2(nextin, 0); @@ -2927,17 +2995,16 @@ static void setup_job_control(void) { pid_t shell_pgrp; - saved_task_pgrp = getpgrp(); + saved_task_pgrp = shell_pgrp = getpgrp(); debug_printf("saved_task_pgrp=%d\n", saved_task_pgrp); fcntl(interactive_fd, F_SETFD, FD_CLOEXEC); - /* Loop until we are in the foreground. */ - while (1) { - shell_pgrp = getpgrp(); - if (tcgetpgrp(interactive_fd) == shell_pgrp) - break; -// and this does... what? need a comment here + /* If we were ran as 'hush &', + * sleep until we are in the foreground. */ + while (tcgetpgrp(interactive_fd) != shell_pgrp) { + /* Send TTIN to ourself (will stop us) */ kill(- shell_pgrp, SIGTTIN); + shell_pgrp = getpgrp(); } /* Ignore job-control and misc signals. */ @@ -2954,6 +3021,8 @@ static void setup_job_control(void) /* Grab control of the terminal. */ tcsetpgrp(interactive_fd, shell_pgrp); + + signal_SA_RESTART(SIGTSTP, handler_ctrl_z); } int hush_main(int argc, char **argv); |