#include "shash.h"
#include "util.h"
+#define THIS_MODULE VLM_fatal_signal
+#include "vlog.h"
+
/* Signals to catch. */
static const int fatal_signals[] = { SIGTERM, SIGINT, SIGHUP, SIGALRM };
/* Registers 'hook' to be called when a process termination signal is raised.
* If 'run_at_exit' is true, 'hook' is also called during normal process
- * termination, e.g. when exit() is called or when main() returns. */
+ * termination, e.g. when exit() is called or when main() returns.
+ *
+ * 'func' will be invoked from an asynchronous signal handler, so it must be
+ * written appropriately. For example, it must not call most C library
+ * functions, including malloc() or free(). */
void
fatal_signal_add_hook(void (*func)(void *aux), void *aux, bool run_at_exit)
{
fatal_signal_unblock();
}
+/* Like fatal_signal_remove_file_to_unlink(), but also unlinks 'file'.
+ * Returns 0 if successful, otherwise a positive errno value. */
+int
+fatal_signal_unlink_file_now(const char *file)
+{
+ int error = unlink(file) ? errno : 0;
+ if (error) {
+ VLOG_WARN("could not unlink \"%s\" (%s)", file, strerror(error));
+ }
+
+ fatal_signal_remove_file_to_unlink(file);
+
+ return error;
+}
+
static void
unlink_files(void *aux UNUSED)
{
do_unlink_files();
}
+/* This is a fatal_signal_add_hook() callback (via unlink_files()). It will be
+ * invoked from an asynchronous signal handler, so it cannot call most C
+ * library functions (unlink() is an explicit exception, see
+ * http://www.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_04.html).
+ * That includes free(), so it doesn't try to free the 'files' data
+ * structure. */
static void
do_unlink_files(void)
{