summaryrefslogtreecommitdiff
path: root/accel-pppd/extra/sigchld.c
diff options
context:
space:
mode:
Diffstat (limited to 'accel-pppd/extra/sigchld.c')
-rw-r--r--accel-pppd/extra/sigchld.c116
1 files changed, 116 insertions, 0 deletions
diff --git a/accel-pppd/extra/sigchld.c b/accel-pppd/extra/sigchld.c
new file mode 100644
index 0000000..abfd42f
--- /dev/null
+++ b/accel-pppd/extra/sigchld.c
@@ -0,0 +1,116 @@
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#include <sys/wait.h>
+
+#include "triton.h"
+#include "spinlock.h"
+#include "log.h"
+
+#include "sigchld.h"
+
+#include "memdebug.h"
+
+static LIST_HEAD(handlers);
+static int lock_refs;
+static pthread_mutex_t handlers_lock = PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t refs_cond = PTHREAD_COND_INITIALIZER;
+static pthread_t sigchld_thr;
+
+static void* sigchld_thread(void *arg)
+{
+ sigset_t set;
+ struct sigchld_handler_t *h, *h0;
+ pid_t pid;
+ int status, sig;
+
+ sigfillset(&set);
+ sigdelset(&set, SIGKILL);
+ sigdelset(&set, SIGSTOP);
+ pthread_sigmask(SIG_BLOCK, &set, NULL);
+
+ sigemptyset(&set);
+ sigaddset(&set, SIGCHLD);
+ sigaddset(&set, SIGQUIT);
+
+ while (1) {
+ pid = waitpid(0, &status, 0);
+ if (pid < 0) {
+ if (errno == EINTR)
+ continue;
+ if (errno == ECHILD) {
+ sigwait(&set, &sig);
+ if (sig == SIGQUIT)
+ break;
+ continue;
+ }
+ log_error("sigchld: waitpid: %s\n", strerror(errno));
+ continue;
+ }
+
+ pthread_mutex_lock(&handlers_lock);
+ while (lock_refs)
+ pthread_cond_wait(&refs_cond, &handlers_lock);
+
+ h0 = NULL;
+ list_for_each_entry(h, &handlers, entry) {
+ if (h->pid == pid) {
+ h0 = h;
+ list_del(&h0->entry);
+ pthread_mutex_lock(&h0->lock);
+ break;
+ }
+ }
+ pthread_mutex_unlock(&handlers_lock);
+ if (h0) {
+ h0->handler(h0, WEXITSTATUS(status));
+ h0->pid = 0;
+ pthread_mutex_unlock(&h0->lock);
+ }
+ }
+
+ return NULL;
+}
+
+void __export sigchld_register_handler(struct sigchld_handler_t *h)
+{
+ pthread_mutex_init(&h->lock, NULL);
+
+ pthread_mutex_lock(&handlers_lock);
+ list_add_tail(&h->entry, &handlers);
+ pthread_mutex_unlock(&handlers_lock);
+}
+
+void __export sigchld_unregister_handler(struct sigchld_handler_t *h)
+{
+ pthread_mutex_lock(&handlers_lock);
+ pthread_mutex_lock(&h->lock);
+ if (h->pid) {
+ list_del(&h->entry);
+ h->pid = 0;
+ }
+ pthread_mutex_unlock(&h->lock);
+ pthread_mutex_unlock(&handlers_lock);
+}
+
+void __export sigchld_lock()
+{
+ pthread_mutex_lock(&handlers_lock);
+ ++lock_refs;
+ pthread_mutex_unlock(&handlers_lock);
+}
+
+void __export sigchld_unlock()
+{
+ pthread_mutex_lock(&handlers_lock);
+ if (--lock_refs == 0)
+ pthread_cond_signal(&refs_cond);
+ pthread_mutex_unlock(&handlers_lock);
+}
+
+static void __init init(void)
+{
+ if (pthread_create(&sigchld_thr, NULL, sigchld_thread, NULL))
+ log_emerg("sigchld: pthread_create: %s\n", strerror(errno));
+}