Add {get,set}domainname(2)
{get,set}domainname aren't in POSIX but are widely-implemented
extensions.
The Linux kernel provides a setdomainname syscall but not a symmetric
getdomainname syscall, since it expects userspace to get the domain name
from uname(2).
Change-Id: I96726c242f4bb646c130b361688328b0b97269a0
Signed-off-by: Greg Hackmann <ghackmann@google.com>
diff --git a/libc/bionic/getdomainname.cpp b/libc/bionic/getdomainname.cpp
new file mode 100644
index 0000000..761a999
--- /dev/null
+++ b/libc/bionic/getdomainname.cpp
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/utsname.h>
+
+int getdomainname(char* name, size_t len) {
+ utsname uts;
+ if (uname(&uts) == -1) return -1;
+
+ // Note: getdomainname()'s behavior varies across implementations when len is
+ // too small. bionic follows the historical libc policy of returning EINVAL,
+ // instead of glibc's policy of copying the first len bytes without a NULL
+ // terminator.
+ if (strlen(uts.domainname) >= len) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ strncpy(name, uts.domainname, len);
+ return 0;
+}