From f627cd77d6a889e97eb1e6b889322e70482d441c Mon Sep 17 00:00:00 2001 From: Ludvig Michaelsson Date: Sun, 21 Nov 2021 10:55:20 +0100 Subject: swaybar: signal status command's process group Make the status command a process group leader and change the kill(2) calls to target the new process group. Signals sent by swaybar will then be received by both the status command and its children, if any. While here, check the result of fork(2). Without this, children spawned by the status command may not receive the signals sent by swaybar. As a result, these children may be orphaned on reload. The issue could be shown by setting the bar to bar { status_command i3status | tee /tmp/i3status.out } which would leave orphaned processes for each reload of sway $ ps o pid,ppid,cmd | grep i3status | grep -v grep 43633 43624 sh -c i3status | tee /tmp/i3status.out 43634 43633 i3status 43635 43633 tee /tmp/i3status.out $ swaymsg reload $ ps o pid,ppid,cmd | grep i3status | grep -v grep 43634 1 i3status 43635 1 tee /tmp/i3status.out 43801 43788 sh -c i3status | tee /tmp/i3status.out 43802 43801 i3status 43803 43801 tee /tmp/i3status.out This fixes #5584. --- swaybar/bar.c | 2 +- swaybar/status_line.c | 11 ++++++++--- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/swaybar/bar.c b/swaybar/bar.c index 15eab782..18b87e6d 100644 --- a/swaybar/bar.c +++ b/swaybar/bar.c @@ -172,7 +172,7 @@ bool determine_bar_visibility(struct swaybar *bar, bool moving_layer) { if (bar->status) { sway_log(SWAY_DEBUG, "Sending %s signal to status command", visible ? "cont" : "stop"); - kill(bar->status->pid, visible ? + kill(-bar->status->pid, visible ? bar->status->cont_signal : bar->status->stop_signal); } } diff --git a/swaybar/status_line.c b/swaybar/status_line.c index ecd91032..a97f3525 100644 --- a/swaybar/status_line.c +++ b/swaybar/status_line.c @@ -157,7 +157,12 @@ struct status_line *status_line_init(char *cmd) { assert(!getenv("WAYLAND_SOCKET") && "display must be initialized before " " starting `status-command`; WAYLAND_SOCKET should not be set"); status->pid = fork(); - if (status->pid == 0) { + if (status->pid < 0) { + sway_log_errno(SWAY_ERROR, "fork failed"); + exit(1); + } else if (status->pid == 0) { + setpgid(0, 0); + dup2(pipe_read_fd[1], STDOUT_FILENO); close(pipe_read_fd[0]); close(pipe_read_fd[1]); @@ -185,8 +190,8 @@ struct status_line *status_line_init(char *cmd) { void status_line_free(struct status_line *status) { status_line_close_fds(status); - kill(status->pid, status->cont_signal); - kill(status->pid, SIGTERM); + kill(-status->pid, status->cont_signal); + kill(-status->pid, SIGTERM); waitpid(status->pid, NULL, 0); if (status->protocol == PROTOCOL_I3BAR) { struct i3bar_block *block, *tmp; -- cgit v1.2.3