Separate libutils and libsystemproperties

native/jni/systemproperties/include/system_properties/system_properties.h

@@ -0,0 +1,90 @@
+/*
+ * 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.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <sys/param.h>
+#include <sys/system_properties.h>
+
+#include "contexts.h"
+#include "contexts_pre_split.h"
+#include "contexts_serialized.h"
+#include "contexts_split.h"
+
+constexpr int PROP_FILENAME_MAX = 1024;
+
+class SystemProperties {
+ public:
+  friend struct LocalPropertyTestState;
+  friend class SystemPropertiesTest;
+  // Note that system properties are initialized before libc calls static initializers, so
+  // doing any initialization in this constructor is an error.  Even a Constructor that zero
+  // initializes this class will clobber the previous property initialization.
+  // We rely on the static SystemProperties in libc to be placed in .bss and zero initialized.
+  SystemProperties() = default;
+  // Special constructor for testing that also zero initializes the important members.
+  explicit SystemProperties(bool initialized) : initialized_(initialized) {
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(SystemProperties);
+
+  bool Init(const char* filename);
+  bool AreaInit(const char* filename, bool* fsetxattr_failed);
+  uint32_t AreaSerial();
+  const prop_info* Find(const char* name);
+  int Read(const prop_info* pi, char* name, char* value);
+  void ReadCallback(const prop_info* pi,
+                    void (*callback)(void* cookie, const char* name, const char* value,
+                                     uint32_t serial),
+                    void* cookie);
+  int Get(const char* name, char* value);
+  int Update(prop_info* pi, const char* value, unsigned int len);
+  int Add(const char* name, unsigned int namelen, const char* value, unsigned int valuelen);
+  int Delete(const char *name);
+  uint32_t Serial(const prop_info* pi);
+  uint32_t WaitAny(uint32_t old_serial);
+  bool Wait(const prop_info* pi, uint32_t old_serial, uint32_t* new_serial_ptr,
+            const timespec* relative_timeout);
+  const prop_info* FindNth(unsigned n);
+  int Foreach(void (*propfn)(const prop_info* pi, void* cookie), void* cookie);
+
+ private:
+  // We don't want to use new or malloc in properties (b/31659220), and we don't want to waste a
+  // full page by using mmap(), so we set aside enough space to create any context of the three
+  // contexts.
+  static constexpr size_t kMaxContextsAlign =
+      MAX(alignof(ContextsSerialized), MAX(alignof(ContextsSplit), alignof(ContextsPreSplit)));
+  static constexpr size_t kMaxContextsSize =
+      MAX(sizeof(ContextsSerialized), MAX(sizeof(ContextsSplit), sizeof(ContextsPreSplit)));
+  alignas(kMaxContextsAlign) char contexts_data_[kMaxContextsSize];
+  Contexts* contexts_;
+
+  bool initialized_;
+  char property_filename_[PROP_FILENAME_MAX];
+};