exec: Spawn processes as direct children (#11735)

* exec: Spawn processes as direct children

Spawn processes as children rather than grandchildren.
This way, spawned processes may track Hyprland's state
by watching their parent, either directly or indirectly
(e.g., Linux's `PR_SET_PDEATH_SIG`).

Fixes #11728

* tests/exec: Add the test on process spawning

Add a test that ensures that:
- A spawned process remains a direct child of Hyprland;
- Upon termination, the process does not become a zombie.
This commit is contained in:
Nikolai Nechaev 2025-09-24 02:32:48 +09:00 committed by GitHub
parent 70a7047ee1
commit 29b103c376
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GPG key ID: B5690EEEBB952194
3 changed files with 95 additions and 38 deletions

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@ -949,17 +949,9 @@ uint64_t CKeybindManager::spawnRawProc(std::string args, PHLWORKSPACE pInitialWo
const auto HLENV = getHyprlandLaunchEnv(pInitialWorkspace);
int socket[2];
if (pipe(socket) != 0) {
Debug::log(LOG, "Unable to create pipe for fork");
}
CFileDescriptor pipeSock[2] = {CFileDescriptor{socket[0]}, CFileDescriptor{socket[1]}};
pid_t child, grandchild;
child = fork();
pid_t child = fork();
if (child < 0) {
Debug::log(LOG, "Fail to create the first fork");
Debug::log(LOG, "Fail to fork");
return 0;
}
if (child == 0) {
@ -970,41 +962,28 @@ uint64_t CKeybindManager::spawnRawProc(std::string args, PHLWORKSPACE pInitialWo
sigemptyset(&set);
sigprocmask(SIG_SETMASK, &set, nullptr);
grandchild = fork();
if (grandchild == 0) {
// run in grandchild
for (auto const& e : HLENV) {
setenv(e.first.c_str(), e.second.c_str(), 1);
}
setenv("WAYLAND_DISPLAY", g_pCompositor->m_wlDisplaySocket.c_str(), 1);
int devnull = open("/dev/null", O_WRONLY | O_CLOEXEC);
if (devnull != -1) {
dup2(devnull, STDOUT_FILENO);
dup2(devnull, STDERR_FILENO);
close(devnull);
}
execl("/bin/sh", "/bin/sh", "-c", args.c_str(), nullptr);
// exit grandchild
_exit(0);
for (auto const& e : HLENV) {
setenv(e.first.c_str(), e.second.c_str(), 1);
}
write(pipeSock[1].get(), &grandchild, sizeof(grandchild));
setenv("WAYLAND_DISPLAY", g_pCompositor->m_wlDisplaySocket.c_str(), 1);
int devnull = open("/dev/null", O_WRONLY | O_CLOEXEC);
if (devnull != -1) {
dup2(devnull, STDOUT_FILENO);
dup2(devnull, STDERR_FILENO);
close(devnull);
}
execl("/bin/sh", "/bin/sh", "-c", args.c_str(), nullptr);
// exit child
_exit(0);
}
// run in parent
read(pipeSock[0].get(), &grandchild, sizeof(grandchild));
// clear child and leave grandchild to init
waitpid(child, nullptr, 0);
if (grandchild < 0) {
Debug::log(LOG, "Fail to create the second fork");
return 0;
}
Debug::log(LOG, "Process Created with pid {}", grandchild);
Debug::log(LOG, "Process Created with pid {}", child);
return grandchild;
return child;
}
SDispatchResult CKeybindManager::killActive(std::string args) {