le2lib: block other signals during signal handler execution

Signed-off-by: Tobias Ulmer <tu@emlix.com>

diff --git a/generic/le2lib.c b/generic/le2lib.c
index ceda311c95b174b7c19d98102a6947ce7d51d48f..233317d44df39a2de0311cad6e66ab6d826aa68f 100644 (file)
--- a/generic/le2lib.c
+++ b/generic/le2lib.c
@@ -806,17 +806,6 @@ static volatile sig_atomic_t signal_received_first = 0;
 static void
 signal_handler(int sig)
 {
-       /*
-        * It's normal for subsequent signals to occur (eg. SIGPIPE)
-        * Ignore signals after they occurred once
-        */
-       struct sigaction sa;
-       sigaction(sig, NULL, &sa);
-       sa.sa_handler = SIG_IGN;
-
-       if (sigaction(sig, &sa, NULL) < 0)
-               fprintf(stderr, "e2: signal_handler: sigaction failed!\n");
-
        /* Make sure we don't install lua_signal_handler more than once */
        if (signal_shutdown)
                return;
@@ -856,8 +845,14 @@ signal_install(lua_State *L)
                sigaddset(&block_set, signals[i]);
 
        sa.sa_handler = signal_handler;
+       /* No SA_RESTART:
+        * In order for e2lib.interrupt_hook() to run on the Lua side, we need
+        * to have some "movement" in the Lua code on interrupt. Thus any
+        * waiting syscalls need to return not only to the C side, but we need
+        * to return EINTR to the Lua side and loop there. */
        sa.sa_flags = 0;
-       sigemptyset(&sa.sa_mask);
+       /* Do not allow other signals during exection of signal_handler */
+       sa.sa_mask = block_set;
 
        for (i = 0; signals[i] != 0; i++) {
                if (sigaction(signals[i], &sa, NULL) < 0) {
@@ -877,7 +872,7 @@ signal_install(lua_State *L)
        return 1;
 }
 
-/* Return the first received signal  triggering shutdown */
+/* Return the first received signal triggering shutdown */
 static int
 signal_received(lua_State *L)
 {