signal.h: Add documentation of signal_pre_select().

[paraslash.git] / signal.h

diff --git a/signal.h b/signal.h
index 50c5f636a84168f637ae26db9a41086d5177580f..742f677a2568cad3001ae9cc2220344ebf7f8b1b 100644 (file)
--- a/signal.h
+++ b/signal.h
@@ -1,13 +1,48 @@
 /*
- * Copyright (C) 2007 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
 /** \file signal.h exported symbols from signal.c */
 
-int para_signal_init(void);
-int para_install_sighandler(int);
-void para_reap_children(void);
-pid_t para_reap_child(void);
-int para_next_signal(void);
+/**
+ * Task for signal handling.
+ */
+struct signal_task {
+       /** The signal pipe. */
+       int fd;
+       /** The associated task structure. */
+       struct task *task;
+};
+
+/**
+ * A generic pre-select method for signal tasks.
+ *
+ * \param s Passed to para_fd_set().
+ * \param context Signal task pointer.
+ *
+ * This convenience helper is called from several programs which need to handle
+ * signals, including para_server and para_audiod. These programs define a
+ * signal task structure and set its ->pre_select method to this function which
+ * adds the file descriptor of the signal task to the set of descriptors to be
+ * watched in the next select() call.
+ *
+ * Although the second parameter must be in fact a pointer to a signal_task
+ * structure, the parameter is specified as void * here to match the
+ * ->pre_select method of struct task.
+ */
+_static_inline_ void signal_pre_select(struct sched *s, void *context)
+{
+       struct signal_task *st = context;
+       para_fd_set(st->fd, &s->rfds, &s->max_fileno);
+}
+
+struct signal_task *signal_init_or_die(void);
+void para_sigaction(int sig, void (*handler)(int));
+void para_install_sighandler(int);
+int para_reap_child(pid_t *pid);
+int para_next_signal(fd_set *rfds);
+void signal_shutdown(struct signal_task *st);
+void para_block_signal(int sig);
+void para_unblock_signal(int sig);