gethostname.c: change to report ENAMETOOLONG error when buflen is less
change to behaviour the same as glibc for the check about buflen
Change-Id: I98265a8fe441df6fed2527686f89b087364ca53d
Signed-off-by: Yongqin Liu <yongqin.liu@linaro.org>
diff --git a/libc/bionic/gethostname.cpp b/libc/bionic/gethostname.cpp
new file mode 100644
index 0000000..962fea1
--- /dev/null
+++ b/libc/bionic/gethostname.cpp
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2008 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 <sys/utsname.h>
+#include <unistd.h>
+
+int gethostname(char* buf, size_t n) {
+ struct utsname name;
+ if (uname(&name) == -1) {
+ return -1;
+ }
+
+ size_t name_length = static_cast<size_t>(strlen(name.nodename) + 1);
+ if (name_length > n) {
+ errno = ENAMETOOLONG;
+ return -1;
+ }
+
+ memcpy(buf, name.nodename, name_length);
+ return 0;
+}