node_internals.h

// Copyright Joyent, Inc. and other Node contributors.
//
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// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
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// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
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#ifndef SRC_NODE_INTERNALS_H_
#define SRC_NODE_INTERNALS_H_

namespace node {

#ifndef offset_of
// g++ in strict mode complains loudly about the system offsetof() macro
// because it uses NULL as the base address.
#define offset_of(type, member) \
  ((intptr_t) ((char *) &(((type *) 8)->member) - 8))
#endif

#ifndef container_of
#define container_of(ptr, type, member) \
  ((type *) ((char *) (ptr) - offset_of(type, member)))
#endif

#ifndef ARRAY_SIZE
#define ARRAY_SIZE(a) (sizeof((a)) / sizeof((a)[0]))
#endif

} // namespace node

#endif // SRC_NODE_INTERNALS_H_