loop: make uloop_run() return the cancelling signal

When a process quits in response to a signal it handles, it should to so
be re-sending the signal to itself. This especially important for SIGINT,
as is explained in [1].

uloop currently hides the reason for quitting uloop_run(). Fix this by
returning the signal that caused the loop to quit (or 0 when uloop_end()
was used), so a program using loop an comply with [1].

[1] https://www.cons.org/cracauer/sigint.html

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>

diff --git a/uloop.c b/uloop.c
index e60fb09705aa8c0dc4768127eeac09f5298ee9e8..0b75d4b3f4bd72f2d7fc33a918b09782c204d9a6 100644 (file)
--- a/uloop.c
+++ b/uloop.c
@@ -58,6 +58,7 @@ static struct list_head processes = LIST_HEAD_INIT(processes);
 
 static int poll_fd = -1;
 bool uloop_cancelled = false;
+static int uloop_status = 0;
 static bool do_sigchld = false;
 
 static struct uloop_fd_event cur_fds[ULOOP_MAX_EVENTS];
@@ -391,6 +392,7 @@ static void uloop_signal_wake(void)
 
 static void uloop_handle_sigint(int signo)
 {
+       uloop_status = signo;
        uloop_cancelled = true;
        uloop_signal_wake();
 }
@@ -506,7 +508,7 @@ static void uloop_clear_processes(void)
                uloop_process_delete(p);
 }
 
-void uloop_run(void)
+int uloop_run(void)
 {
        static int recursive_calls = 0;
        struct timeval tv;
@@ -518,8 +520,9 @@ void uloop_run(void)
        if (!recursive_calls++)
                uloop_setup_signals(true);
 
+       uloop_status = 0;
        uloop_cancelled = false;
-       while(!uloop_cancelled)
+       while (!uloop_cancelled)
        {
                uloop_gettime(&tv);
                uloop_process_timeouts(&tv);
@@ -536,6 +539,8 @@ void uloop_run(void)
 
        if (!--recursive_calls)
                uloop_setup_signals(false);
+
+       return uloop_status;
 }
 
 void uloop_done(void)

diff --git a/uloop.h b/uloop.h
index 756451405381015cb02f390ad43298ec02ae1ef8..2f1eb4c49e12896d11e64bb8e16c0fd8e76b0ef0 100644 (file)
--- a/uloop.h
+++ b/uloop.h
@@ -103,7 +103,7 @@ static inline void uloop_end(void)
 }
 
 int uloop_init(void);
-void uloop_run(void);
+int uloop_run(void);
 void uloop_done(void);
 
 #endif