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>
This commit is contained in:
Matthias Schiffer 2016-06-21 17:19:11 +02:00 committed by Felix Fietkau
parent 1f019ceea1
commit 1ad3d93eb8
2 changed files with 8 additions and 3 deletions

View file

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

View file

@ -103,7 +103,7 @@ static inline void uloop_end(void)
} }
int uloop_init(void); int uloop_init(void);
void uloop_run(void); int uloop_run(void);
void uloop_done(void); void uloop_done(void);
#endif #endif