first commit

1 files changed, 166 insertions, 0 deletions

diff --git a/src/subprocs.c b/src/subprocs.c
new file mode 100644
index 0000000..757daf8
--- /dev/null
+++ b/src/subprocs.c
@@ -0,0 +1,166 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 8 -*-
+ *
+ * subprocs.c --- choosing, spawning, and killing screenhacks.
+ *
+ * xscreensaver, Copyright (c) 1991-2003 Jamie Zawinski <[email protected]>
+ * Modified:     Copyright (c) 2004 William Jon McCann <[email protected]>
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation.  No representations are made about the suitability of this
+ * software for any purpose.  It is provided "as is" without express or
+ * implied warranty.
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+
+#ifndef ESRCH
+# include <errno.h>
+#endif
+
+#include <sys/time.h>		/* sys/resource.h needs this for timeval */
+# include <sys/wait.h>		/* for waitpid() and associated macros */
+
+#ifdef VMS
+# include <processes.h>
+# include <unixio.h>		/* for close */
+# include <unixlib.h>		/* for getpid */
+# define pid_t int
+# define fork  vfork
+#endif /* VMS */
+
+#include <signal.h>		/* for the signal names */
+
+#include <glib.h>
+#include "subprocs.h"
+
+#if !defined(SIGCHLD) && defined(SIGCLD)
+# define SIGCHLD SIGCLD
+#endif
+
+/* Semaphore to temporarily turn the SIGCHLD handler into a no-op.
+   Don't alter this directly -- use block_sigchld() / unblock_sigchld().
+*/
+static int block_sigchld_handler = 0;
+
+
+#ifdef HAVE_SIGACTION
+sigset_t
+#else  /* !HAVE_SIGACTION */
+int
+#endif /* !HAVE_SIGACTION */
+block_sigchld (void)
+{
+#ifdef HAVE_SIGACTION
+	sigset_t child_set;
+	sigemptyset (&child_set);
+	sigaddset (&child_set, SIGCHLD);
+	sigaddset (&child_set, SIGPIPE);
+	sigprocmask (SIG_BLOCK, &child_set, 0);
+#endif /* HAVE_SIGACTION */
+
+	block_sigchld_handler++;
+
+#ifdef HAVE_SIGACTION
+	return child_set;
+#else  /* !HAVE_SIGACTION */
+	return 0;
+#endif /* !HAVE_SIGACTION */
+}
+
+void
+unblock_sigchld (void)
+{
+#ifdef HAVE_SIGACTION
+	sigset_t child_set;
+	sigemptyset (&child_set);
+	sigaddset (&child_set, SIGCHLD);
+	sigaddset (&child_set, SIGPIPE);
+	sigprocmask (SIG_UNBLOCK, &child_set, 0);
+#endif /* HAVE_SIGACTION */
+
+	block_sigchld_handler--;
+}
+
+int
+signal_pid (int    pid,
+            int    signal)
+{
+	int status = -1;
+	gboolean verbose = TRUE;
+
+	if (block_sigchld_handler)
+		/* This function should not be called from the signal handler. */
+		abort();
+
+	block_sigchld ();                      /* we control the horizontal... */
+
+	status = kill (pid, signal);
+
+	if (verbose && status < 0)
+	{
+		if (errno == ESRCH)
+			g_message ("Child process %lu was already dead.",
+			           (unsigned long) pid);
+		else
+		{
+			char buf [1024];
+			snprintf (buf, sizeof (buf), "Couldn't kill child process %lu",
+			          (unsigned long) pid);
+			perror (buf);
+		}
+	}
+
+	unblock_sigchld ();
+
+	if (block_sigchld_handler < 0)
+		abort ();
+
+	return status;
+}
+
+#ifndef VMS
+
+void
+await_dying_children (int      pid,
+                      gboolean debug)
+{
+	while (1)
+	{
+		int wait_status = 0;
+		pid_t kid;
+
+		errno = 0;
+		kid = waitpid (-1, &wait_status, WNOHANG|WUNTRACED);
+
+		if (debug)
+		{
+			if (kid < 0 && errno)
+				g_message ("waitpid(%d) ==> %ld (%d)", pid, (long) kid, errno);
+			else if (kid != 0)
+				g_message ("waitpid(%d) ==> %ld", pid, (long) kid);
+		}
+
+		/* 0 means no more children to reap.
+		   -1 means error -- except "interrupted system call" isn't a "real"
+		   error, so if we get that, we should just try again. */
+		if (kid < 0 && errno != EINTR)
+			break;
+	}
+}
+
+
+#else  /* VMS */
+static void await_dying_children (saver_info *si)
+{
+	return;
+}
+#endif /* VMS */
+