Create a lib that uses scudo instead of jemalloc.

The media processes already use scudo as their allocator. However, it
doesn't really correctly replace the normal allocation functions, so create
a set of wrappers that allow us to use scudo closer to how jemalloc is used.

This is only a temporary change, and should be removed for the next
release of Android. In that version, we will be using standalone
scudo which won't require this wrapper code.

Bug: 123689570

Test: Ran new bionic unit tests. There are failures, but only with
Test: extensions that scudo does not support.

Change-Id: I0516c23d654a9b6c69b157c5501245d2e0b3d264
diff --git a/libc/bionic/scudo/scudo.cpp b/libc/bionic/scudo/scudo.cpp
new file mode 100644
index 0000000..fb09b92
--- /dev/null
+++ b/libc/bionic/scudo/scudo.cpp
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2019 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 <malloc.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/param.h>
+#include <sys/prctl.h>
+
+#include "private/bionic_macros.h"
+
+#include "scudo.h"
+
+// Disable Scudo's mismatch allocation check, as it is being triggered
+// by some third party code.
+extern "C" const char *__scudo_default_options() {
+  return "DeallocationTypeMismatch=false";
+}
+
+static inline bool AllocTooBig(size_t bytes) {
+#if defined(__LP64__)
+  if (__predict_false(bytes > 0x10000000000ULL)) {
+#else
+  if (__predict_false(bytes > 0x80000000ULL)) {
+#endif
+    return true;
+  }
+  return false;
+}
+
+void* scudo_aligned_alloc(size_t alignment, size_t size) {
+  if (alignment == 0 || !powerof2(alignment) || (size % alignment) != 0) {
+    errno = EINVAL;
+    return nullptr;
+  }
+  if (AllocTooBig(size)) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+
+  return aligned_alloc(alignment, size);
+}
+
+void* scudo_calloc(size_t item_count, size_t item_size) {
+  size_t total;
+  if (__builtin_mul_overflow(item_count, item_size, &total) || AllocTooBig(total)) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  return calloc(item_count, item_size);
+}
+
+void scudo_free(void* ptr) {
+  free(ptr);
+}
+
+extern "C" size_t __sanitizer_get_current_allocated_bytes();
+extern "C" size_t __sanitizer_get_heap_size();
+
+struct mallinfo scudo_mallinfo() {
+  struct mallinfo info {};
+  info.uordblks = __sanitizer_get_current_allocated_bytes();
+  info.hblkhd = __sanitizer_get_heap_size();
+  info.usmblks = info.hblkhd;
+  return info;
+}
+
+void* scudo_malloc(size_t byte_count) {
+  if (AllocTooBig(byte_count)) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  return malloc(byte_count);
+}
+
+size_t scudo_malloc_usable_size(const void* ptr) {
+  return malloc_usable_size(ptr);
+}
+
+void* scudo_memalign(size_t alignment, size_t byte_count) {
+  if (AllocTooBig(byte_count)) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  if (alignment != 0) {
+    if (!powerof2(alignment)) {
+      alignment = BIONIC_ROUND_UP_POWER_OF_2(alignment);
+    }
+  } else {
+    alignment = 1;
+  }
+  return memalign(alignment, byte_count);
+}
+
+void* scudo_realloc(void* ptr, size_t byte_count) {
+  if (AllocTooBig(byte_count)) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  return realloc(ptr, byte_count);
+}
+
+int scudo_posix_memalign(void** memptr, size_t alignment, size_t size) {
+  if (alignment < sizeof(void*) || !powerof2(alignment)) {
+    return EINVAL;
+  }
+  if (AllocTooBig(size)) {
+    return ENOMEM;
+  }
+  return posix_memalign(memptr, alignment, size);
+}
+
+#if defined(HAVE_DEPRECATED_MALLOC_FUNCS)
+extern "C" void* pvalloc(size_t);
+
+void* scudo_pvalloc(size_t size) {
+  if (AllocTooBig(size)) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  return pvalloc(size);
+}
+
+extern "C" void* valloc(size_t);
+
+void* scudo_valloc(size_t size) {
+  if (AllocTooBig(size)) {
+    errno = ENOMEM;
+    return nullptr;
+  }
+  return valloc(size);
+}
+#endif
+
+// Do not try and name the scudo maps by overriding __sanitizer::internal_mmap.
+// There is already a function called MmapNamed that names the maps.
+// Unfortunately, there is no easy way to override MmapNamed because
+// too much of the code is not compiled into functions available in the
+// library, and the code is complicated.