diff options
Diffstat (limited to 'shell')
| -rw-r--r-- | shell/hush.c | 48 |
1 files changed, 28 insertions, 20 deletions
diff --git a/shell/hush.c b/shell/hush.c index 80a3992..e6be700 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -1829,12 +1829,13 @@ static void restore_G_args(save_arg_t *sv, char **argv) * SIGQUIT: ignore * SIGTERM (interactive): ignore * SIGHUP (interactive): - * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit -//HUP: we don't need to do this, kernel does this for us -//HUP: ("orphaned process group" handling according to POSIX). -//HUP: We still have a SIGHUP handler, just to have tty pgrp restored -//HUP: (otherwise e.g. Midnight Commander backgrounds when hush -//HUP: started from it gets killed by SIGHUP). + * Send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit. + * Kernel would do this for us ("orphaned process group" handling + * according to POSIX) if we are a session leader and thus our death + * frees the controlling tty, but to be bash-compatible, we also do it + * for every interactive shell's death by SIGHUP. + * (Also, we need to restore tty pgrp, otherwise e.g. Midnight Commander + * backgrounds when hush started from it gets killed by SIGHUP). * 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. Try this in bash: @@ -2183,20 +2184,27 @@ static int check_and_run_traps(void) break; #if ENABLE_HUSH_JOB case SIGHUP: { -//HUP//TODO: why are we doing this? ash and dash don't do this, -//HUP//they have no handler for SIGHUP at all, -//HUP//they rely on kernel to send SIGHUP+SIGCONT to orphaned process groups -//HUP struct pipe *job; -//HUP debug_printf_exec("%s: sig:%d default SIGHUP handler\n", __func__, sig); -//HUP /* bash is observed to signal whole process groups, -//HUP * not individual processes */ -//HUP for (job = G.job_list; job; job = job->next) { -//HUP if (job->pgrp <= 0) -//HUP continue; -//HUP debug_printf_exec("HUPing pgrp %d\n", job->pgrp); -//HUP if (kill(- job->pgrp, SIGHUP) == 0) -//HUP kill(- job->pgrp, SIGCONT); -//HUP } + /* if (G_interactive_fd) - no need to check, the handler + * is only installed if we *are* interactive */ + { + /* bash compat: "Before exiting, an interactive + * shell resends the SIGHUP to all jobs, running + * or stopped. Stopped jobs are sent SIGCONT + * to ensure that they receive the SIGHUP." + */ + struct pipe *job; + debug_printf_exec("%s: sig:%d default SIGHUP handler\n", __func__, sig); + /* bash is observed to signal whole process groups, + * not individual processes */ + for (job = G.job_list; job; job = job->next) { + if (job->pgrp <= 0) + continue; + debug_printf_exec("HUPing pgrp %d\n", job->pgrp); + if (kill(- job->pgrp, SIGHUP) == 0) + kill(- job->pgrp, SIGCONT); + } + } + /* this restores tty pgrp, then kills us with SIGHUP */ sigexit(SIGHUP); } #endif |