From b7055b02a3ef6613835f542ca2ef82716a24a03c Mon Sep 17 00:00:00 2001
From: Ben Kibbey <bjk@luxsci.net>
Date: Wed, 10 Oct 2007 20:11:48 -0400
Subject: [PATCH] Use sigaction(2) in the parent process. A child process no
 longer calls log_write() from it's signal handler or right before exit.
 Instead the parent process logs the pid and exit status.

---
 src/pwmd.c | 36 +++++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 15 deletions(-)

diff --git a/src/pwmd.c b/src/pwmd.c
index a1bcfd89..b8fb7206 100644
--- a/src/pwmd.c
+++ b/src/pwmd.c
@@ -176,7 +176,7 @@ void log_write(const gchar *fmt, ...)
  * The pthreads docs say mutex locking isn't recommended in a signal handler
  * because it's not asyncronise. So don't flood pwmd will a bunch of signals.
  */
-static void catchsig(gint sig)
+static void catchsig(gint sig, siginfo_t *info, gpointer uctx)
 {
     gint status;
 
@@ -204,13 +204,15 @@ static void catchsig(gint sig)
 	case SIGCHLD:
 	    waitpid(-1, &status, 0);
 
-	    if (WIFEXITED(status) || WIFSIGNALED(status))
+	    if (WIFEXITED(status) || WIFSIGNALED(status)) {
 		clients--;
+		log_write(N_("pid %i exited with status %i"), info->si_pid, info->si_status);
+	    }
 
 	    break;
 	case SIGHUP:
-	    log_write(N_("clearing file cache"));
 	    MUTEX_LOCK(NULL);
+	    log_write(N_("clearing file cache"));
 	    cache_clear(NULL, 2);
 	    MUTEX_UNLOCK;
 	    break;
@@ -264,23 +266,24 @@ static void setup_gcrypt()
 static void child_catchsig(int sig)
 {
     assuan_context_t ctx = global_client->ctx;
+    gint ret = EXIT_FAILURE;
 
     switch (sig) {
 	case SIGTERM:
+	    ret = EXIT_SUCCESS;
 	case SIGPIPE:
 	    MUTEX_UNLOCK;
 	    cleanup_assuan(ctx);
 	    g_free(global_client);
 	    assuan_deinit_server(ctx);
-	    log_write(N_("exiting"));
-	    _exit(EXIT_SUCCESS);
+	    _exit(ret);
 	    break;
 	case SIGABRT:
 	    MUTEX_UNLOCK;
 #ifndef MEM_DEBUG
 	    xpanic();
 #endif
-	    exit(EXIT_FAILURE);
+	    _exit(EXIT_FAILURE);
 	default:
 	    break;
     }
@@ -374,7 +377,6 @@ done:
 
     g_free(cl);
     assuan_deinit_server(ctx);
-    log_write(N_("exiting"));
     _exit(EXIT_SUCCESS);
 }
 
@@ -994,6 +996,7 @@ int main(int argc, char *argv[])
     gint default_timeout;
     gint rcfile_spec = 0;
     gint estatus = EXIT_FAILURE;
+    struct sigaction sact;
 #ifndef MEM_DEBUG
     GMemVTable mtable = { xmalloc, xrealloc, xfree, xcalloc, NULL, NULL };
 #endif
@@ -1274,13 +1277,16 @@ int main(int argc, char *argv[])
 	goto do_exit;
     }
 
-    signal(SIGCHLD, catchsig);
-    signal(SIGTERM, catchsig);
-    signal(SIGINT, catchsig);
-    signal(SIGHUP, catchsig);
-    signal(SIGALRM, catchsig);
-    signal(SIGABRT, catchsig);
-    signal(SIGUSR1, catchsig);
+    memset(&sact, 0, sizeof(struct sigaction));
+    sact.sa_flags = SA_SIGINFO;
+    sact.sa_sigaction = catchsig;
+    sigaction(SIGCHLD, &sact, NULL);
+    sigaction(SIGTERM, &sact, NULL);
+    sigaction(SIGINT, &sact, NULL);
+    sigaction(SIGHUP, &sact, NULL);
+    sigaction(SIGALRM, &sact, NULL);
+    sigaction(SIGABRT, &sact, NULL);
+    sigaction(SIGUSR1, &sact, NULL);
     alarm(1);
 
     if (background) {
@@ -1310,7 +1316,7 @@ int main(int argc, char *argv[])
 	    if (quit)
 		break;
 
-	    if (errno == EAGAIN)
+	    if (errno == EAGAIN || errno == EINTR)
 		continue;
 
 	    log_write("accept(): %s", strerror(errno));
-- 
2.11.4.GIT