upload android base code part3

android/bionic/linker/linker_memory.cpp

@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2015 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 "linker_allocator.h"
+
+#include <stdlib.h>
+#include <sys/cdefs.h>
+#include <unistd.h>
+
+#include <async_safe/log.h>
+
+static LinkerMemoryAllocator g_linker_allocator;
+static pid_t fallback_tid = 0;
+
+// Used by libdebuggerd_handler to switch allocators during a crash dump, in
+// case the linker heap is corrupted. Do not use this function.
+extern "C" void __linker_enable_fallback_allocator() {
+  if (fallback_tid != 0) {
+    async_safe_fatal("attempted to use currently-in-use fallback allocator");
+  }
+
+  fallback_tid = gettid();
+}
+
+extern "C" void __linker_disable_fallback_allocator() {
+  if (fallback_tid == 0) {
+    async_safe_fatal("attempted to disable unused fallback allocator");
+  }
+
+  fallback_tid = 0;
+}
+
+static LinkerMemoryAllocator& get_fallback_allocator() {
+  static LinkerMemoryAllocator fallback_allocator;
+  return fallback_allocator;
+}
+
+static LinkerMemoryAllocator& get_allocator() {
+  if (__predict_false(fallback_tid) && __predict_false(gettid() == fallback_tid)) {
+    return get_fallback_allocator();
+  }
+  return g_linker_allocator;
+}
+
+void* malloc(size_t byte_count) {
+  return get_allocator().alloc(byte_count);
+}
+
+void* calloc(size_t item_count, size_t item_size) {
+  return get_allocator().alloc(item_count*item_size);
+}
+
+void* realloc(void* p, size_t byte_count) {
+  return get_allocator().realloc(p, byte_count);
+}
+
+void free(void* ptr) {
+  get_allocator().free(ptr);
+}
+