/*
- * Copyright (C) 2004-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2004-2011 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
#include <signal.h>
#include <sys/types.h>
-#include <dirent.h>
#include "para.h"
#include "error.h"
}
/**
- * Return the number of next pending signal.
+ * Block a signal for the caller.
*
- * This should be called if the fd for the signal pipe is ready for reading.
+ * \param sig The signal to block.
*
- * \return On success, the number of the received signal is returned. If the
- * read returned zero or was interrupted by another signal the function returns
- * 0. Otherwise, a negative error value is returned.
+ * This sets the given signal in the current signal mask of the calling process
+ * to prevent this signal from delivery.
+ *
+ * \sa \ref para_unblock_signal(), sigprocmask(2), sigaddset(3).
*/
-int para_next_signal(void)
+void para_block_signal(int sig)
{
- int s;
- ssize_t r = read(signal_pipe[0], &s, sizeof(s));
+ sigset_t set;
- if (!r) {
- PARA_CRIT_LOG("read from signal pipe returned zero\n");
- return 0;
- }
- if (r < 0) {
- if (errno == EAGAIN || errno == EINTR)
- return 0;
- return -ERRNO_TO_PARA_ERROR(errno);
+ PARA_DEBUG_LOG("blocking signal %d\n", sig);
+ sigemptyset(&set);
+ sigaddset(&set, sig);
+ sigprocmask(SIG_BLOCK, &set, NULL);
+}
+
+/**
+ * Unblock a signal.
+ *
+ * \param sig The signal to unblock.
+ *
+ * This function removes the given signal from the current set of blocked
+ * signals.
+ *
+ * \sa \ref para_block_signal(), sigprocmask(2), sigaddset(3).
+ */
+void para_unblock_signal(int sig)
+{
+ sigset_t set;
+
+ PARA_DEBUG_LOG("unblocking signal %d\n", sig);
+ sigemptyset(&set);
+ sigaddset(&set, sig);
+ sigprocmask(SIG_UNBLOCK, &set, NULL);
+}
+
+/**
+ * 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)
+{
+ size_t n;
+ int s, ret = read_nonblock(signal_pipe[0], &s, sizeof(s), rfds, &n);
+
+ if (ret < 0) {
+ PARA_EMERG_LOG("%s\n", para_strerror(-ret));
+ exit(EXIT_FAILURE);
}
- assert(r == sizeof(s));
+ if (n == 0)
+ return 0;
+ assert(n == sizeof(s));
PARA_DEBUG_LOG("next signal: %d\n", s);
return s;
}