Fix GNU/POSIX basename headers.

Including glibc's <libgen.h> will result in the user getting the POSIX
version of basename always, regardless of when it is included relative
to <string.h>. Prior to this patch, our implementation would result in
the one that's included first winning.

Bug: http://b/25459151
Change-Id: Id4aaf1670dad317d6bbc05763a84ee87596e8e59

1 files changed, 89 insertions, 0 deletions

diff --git a/tests/libgen_basename_test.cpp b/tests/libgen_basename_test.cpp
new file mode 100644
index 0000000..55939d1
--- /dev/null
+++ b/tests/libgen_basename_test.cpp
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _GNU_SOURCE
+  #define _GNU_SOURCE 1
+#endif
+
+#include <string.h>
+
+#if defined(basename)
+  #error basename should not be defined at this point
+#endif
+
+static const char* gnu_basename(const char* in) {
+  return basename(in);
+}
+
+#include <libgen.h>
+
+#if !defined(basename)
+  #error basename should be defined at this point
+#endif
+
+static char* posix_basename(char* in) {
+  return basename(in);
+}
+
+#include <errno.h>
+#include <gtest/gtest.h>
+
+static void __TestGnuBasename(const char* in, const char* expected_out, int line) {
+  const char* out = gnu_basename(in);
+  ASSERT_STREQ(expected_out, out) << "(" << line << "): " << in << std::endl;
+  ASSERT_EQ(0, errno) << "(" << line << "): " << in << std::endl;
+}
+
+static void __TestPosixBasename(const char* in, const char* expected_out, int line) {
+  char* writable_in = (in != NULL) ? strdup(in) : NULL;
+  errno = 0;
+  const char* out = posix_basename(&writable_in[0]);
+  ASSERT_STREQ(expected_out, out) << "(" << line << "): " << in << std::endl;
+  ASSERT_EQ(0, errno) << "(" << line << "): " << in << std::endl;
+  free(writable_in);
+}
+
+#define TestGnuBasename(in, expected) __TestGnuBasename(in, expected, __LINE__)
+#define TestPosixBasename(in, expected) __TestPosixBasename(in, expected, __LINE__)
+
+TEST(libgen_basename, gnu_basename) {
+  // GNU's basename doesn't accept NULL
+  // TestGnuBasename(NULL, ".");
+  TestGnuBasename("", "");
+  TestGnuBasename("/usr/lib", "lib");
+  TestGnuBasename("/system/bin/sh/", "");
+  TestGnuBasename("/usr/", "");
+  TestGnuBasename("usr", "usr");
+  TestGnuBasename("/", "");
+  TestGnuBasename(".", ".");
+  TestGnuBasename("..", "..");
+  TestGnuBasename("///", "");
+  TestGnuBasename("//usr//lib//", "");
+}
+
+TEST(libgen_basename, posix_basename) {
+  TestPosixBasename(NULL, ".");
+  TestPosixBasename("", ".");
+  TestPosixBasename("/usr/lib", "lib");
+  TestPosixBasename("/system/bin/sh/", "sh");
+  TestPosixBasename("/usr/", "usr");
+  TestPosixBasename("usr", "usr");
+  TestPosixBasename("/", "/");
+  TestPosixBasename(".", ".");
+  TestPosixBasename("..", "..");
+  TestPosixBasename("///", "/");
+  TestPosixBasename("//usr//lib//", "lib");
+}