1 files changed, 121 insertions, 0 deletions
diff --git a/lib/util/locking.c b/lib/util/locking.c
new file mode 100644
index 0000000..64499e6
--- /dev/null
+++ b/lib/util/locking.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 1999-2005, 2007, 2009-2015
+ *	Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Sponsored in part by the Defense Advanced Research Projects
+ * Agency (DARPA) and Air Force Research Laboratory, Air Force
+ * Materiel Command, USAF, under agreement number F39502-99-1-0512.
+ */
+
+/*
+ * This is an open source non-commercial project. Dear PVS-Studio, please check it.
+ * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <stdlib.h>
+#ifdef HAVE_STRING_H
+# include <string.h>
+#endif /* HAVE_STRING_H */
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif /* HAVE_STRING_H */
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "sudo_compat.h"
+#include "sudo_util.h"
+#include "sudo_debug.h"
+
+/*
+ * Lock/unlock all or part of a file.
+ */
+#ifdef HAVE_LOCKF
+bool
+sudo_lock_file_v1(int fd, int type)
+{
+    return sudo_lock_region_v1(fd, type, 0);
+}
+
+bool
+sudo_lock_region_v1(int fd, int type, off_t len)
+{
+    int op;
+    debug_decl(sudo_lock_region, SUDO_DEBUG_UTIL)
+
+    switch (type) {
+	case SUDO_LOCK:
+	    op = F_LOCK;
+	    break;
+	case SUDO_TLOCK:
+	    op = F_TLOCK;
+	    break;
+	case SUDO_UNLOCK:
+	    op = F_ULOCK;
+	    break;
+	default:
+	    errno = EINVAL;
+	    debug_return_bool(false);
+    }
+    debug_return_bool(lockf(fd, op, len) == 0);
+}
+#else
+bool
+sudo_lock_file_v1(int fd, int type)
+{
+    return sudo_lock_region_v1(fd, type, 0);
+}
+
+bool
+sudo_lock_region_v1(int fd, int type, off_t len)
+{
+    struct flock lock;
+    int func;
+    debug_decl(sudo_lock_file, SUDO_DEBUG_UTIL)
+
+    switch (type) {
+	case SUDO_LOCK:
+	    lock.l_type = F_WRLCK;
+	    func = F_SETLKW;
+	    break;
+	case SUDO_TLOCK:
+	    lock.l_type = F_WRLCK;
+	    func = F_SETLK;
+	    break;
+	case SUDO_UNLOCK:
+	    lock.l_type = F_UNLCK;
+	    func = F_SETLK;
+	    break;
+	default:
+	    errno = EINVAL;
+	    debug_return_bool(false);
+    }
+    lock.l_start = 0;
+    lock.l_len = len;
+    lock.l_pid = 0;
+    lock.l_whence = len ? SEEK_CUR : SEEK_SET;
+
+    debug_return_bool(fcntl(fd, func, &lock) == 0);
+}
+#endif