fdisk: make SIGINT handler signal-safe

Checking debug options and calling fprintf is not signal-safe.
Install a debug handler if debugging is requested and use signal-safe
output in it.

Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>

diff --git a/disk-utils/fdisk.c b/disk-utils/fdisk.c
index f44a4899ebf1874083478079a9e831b2b09e6be5..d46a468e8ab00409af61f6b4d1f7d1d8c1bf2755 100644 (file)
--- a/disk-utils/fdisk.c
+++ b/disk-utils/fdisk.c
@@ -81,7 +81,13 @@ static void fdiskprog_init_debug(void)
 
 static void reply_sighandler(int sig __attribute__((unused)))
 {
-       DBG(ASK, ul_debug("got signal"));
+       /* nothing to do here */
+}
+
+static void reply_debug_sighandler(int sig __attribute__((unused)))
+{
+       /* signal-safe version of DBG(ASK, ul_debug("got signal")) */
+       ul_sig_printf("%d: %s: %8s: %s\n", getpid(), "fdisk", "ASK", "got signal");
 }
 
 static int reply_running;
@@ -111,6 +117,7 @@ int get_user_reply(const char *prompt, char *buf, size_t bufsz)
        DBG(ASK, ul_debug("asking for user reply %s", is_interactive ? "[interactive]" : ""));
 
        sigemptyset(&act.sa_mask);
+       ON_DBG(ASK, act.sa_handler = reply_debug_sighandler);
        sigaction(SIGINT, &act, &oldact);
 
 #ifdef HAVE_LIBREADLINE