Android does not always provide posix_memalign

Summary: We could provide `posix_memalign` instead as part of portability, but I am not sure how to tell whether or not it will be available.

Reviewed By: yfeldblum

Differential Revision: D2991432

fb-gh-sync-id: 587314d43779f3b8fead2c41ed05016e6350f2ee
shipit-source-id: 587314d43779f3b8fead2c41ed05016e6350f2ee

folly/Makefile.am

@@ -268,6 +268,7 @@ nobase_follyinclude_HEADERS = \
 	portability/Constexpr.h \
 	portability/Environment.h \
 	portability/GFlags.h \
+	portability/Stdlib.h \
 	portability/Syscall.h \
 	portability/SysTime.h \
 	portability/SysUio.h \
@@ -397,6 +398,7 @@ libfolly_la_SOURCES = \
 	MacAddress.cpp \
 	MemoryMapping.cpp \
 	portability/Environment.cpp \
+	portability/Stdlib.cpp \
 	portability/SysTime.cpp \
 	portability/Time.cpp \
 	Random.cpp \

folly/portability/Stdlib.cpp

+/*
+ * Copyright 2016 Facebook, Inc.
+ *
+ * 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.
+ */
+
+#include <folly/portability/Stdlib.h>
+
+#include <errno.h>
+
+#if defined(__ANDROID__)
+
+#include <android/api-level.h>
+
+#if (__ANDROID_API__ <= 15)
+
+int posix_memalign(void** memptr, size_t alignment, size_t size) {
+  int rc = 0;
+  int saved_errno = errno;
+  void* ptr = nullptr;
+  ptr = memalign(alignment, size);
+  if (nullptr == ptr) {
+    rc = errno;
+  } else {
+    *memptr = ptr;
+  }
+  errno = saved_errno;
+  return rc;
+}
+
+#endif
+#endif

folly/portability/Stdlib.h

+/*
+ * Copyright 2016 Facebook, Inc.
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include <cstdlib>
+
+extern int posix_memalign(void** memptr, size_t alignment, size_t size);

folly/test/RangeTest.cpp

@@ -19,9 +19,10 @@
 
 #include <folly/Range.h>
 
+#include <folly/portability/Stdlib.h>
+
 #include <sys/mman.h>
 #include <array>
-#include <cstdlib>
 #include <iterator>
 #include <limits>
 #include <random>