X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=signal.c;h=d9a6aa37057415117c32a6a18c33d81977499392;hb=6bbc7c29dd69ed34ef90dac72951abbfd7cc1877;hp=4e876cfe6f6d01cb6b51ca05c283a8a466e7b286;hpb=26a032fffa6c6e6f092ed3d14c2b5f08e5c736d6;p=paraslash.git diff --git a/signal.c b/signal.c index 4e876cfe..d9a6aa37 100644 --- a/signal.c +++ b/signal.c @@ -27,7 +27,7 @@ static int signal_pipe[2]; * signal arrives, the signal handler writes the number of the signal received * to one end of the signal pipe. The application can test for pending signals * by checking if the file descriptor of the other end of the signal pipe is - * ready for reading, see select(2). + * ready for reading. * * \return This function either succeeds or calls exit(3) to terminate the * current process. On success, a signal task structure is returned. @@ -72,10 +72,13 @@ static void generic_signal_handler(int s) errno = save_errno; return; } - if (ret < 0) - PARA_EMERG_LOG("%s\n", strerror(errno)); - else - PARA_EMERG_LOG("short write to signal pipe\n"); + /* + * This is a fatal error which should never happen. We must not call + * PARA_XXX_LOG() here because this might acquire the log mutex which + * is already taken by the main program if the interrupt occurs while a + * log message is being printed. The mutex will not be released as long + * as this signal handler is running, so a deadlock ensues. + */ exit(EXIT_FAILURE); } @@ -202,16 +205,14 @@ void para_unblock_signal(int sig) /** * Return the number of the next pending signal. * - * \param rfds The fd_set containing the signal pipe. - * * \return On success, the number of the received signal is returned. If there * is no signal currently pending, the function returns zero. On read errors * from the signal pipe, the process is terminated. */ -int para_next_signal(fd_set *rfds) +int para_next_signal(void) { size_t n; - int s, ret = read_nonblock(signal_pipe[0], &s, sizeof(s), rfds, &n); + int s, ret = read_nonblock(signal_pipe[0], &s, sizeof(s), &n); if (ret < 0) { PARA_EMERG_LOG("%s\n", para_strerror(-ret));