Merge branch 't/web_fix'

[paraslash.git] / signal.c

diff --git a/signal.c b/signal.c
index 59a0d45aba7ad975fc287862308891435c4e9095..0b7b47fa3d1401d57ae11ed107f487e9036a2870 100644 (file)
--- a/signal.c
+++ b/signal.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2004-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2004-2012 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -7,7 +7,6 @@
 
 #include <signal.h>
 #include <sys/types.h>
-#include <dirent.h>
 
 #include "para.h"
 #include "error.h"
@@ -102,20 +101,6 @@ int para_reap_child(pid_t *pid)
        return 1;
 }
 
-/**
- * Paraslash's zombie killer.
- *
- * It just calls \p para_reap_child() until there are no more children left to
- * reap.
- */
-void para_reap_children(void)
-{
-       pid_t pid;
-
-       while (para_reap_child(&pid) > 0)
-               ; /* nothing */
-}
-
 /**
  * Install the given handler for the given signal.
  *
@@ -163,29 +148,66 @@ void para_install_sighandler(int sig)
 }
 
 /**
- * Return the number of next pending signal.
+ * Block a signal for the caller.
+ *
+ * \param sig The signal to block.
  *
- * This should be called if the fd for the signal pipe is ready for reading.
+ * This sets the given signal in the current signal mask of the calling process
+ * to prevent this signal from delivery.
  *
- * \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.
+ * \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;
 }