diff options
author | Boris Kolpackov <boris@codesynthesis.com> | 2009-09-06 12:52:53 +0200 |
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committer | Boris Kolpackov <boris@codesynthesis.com> | 2009-09-06 12:52:53 +0200 |
commit | cb9ea47e7825b5073d4d645afb94f6326cb7cf4d (patch) | |
tree | 201c215b08df918924153a60520046c294438a6b /cutl/shared-ptr/base.cxx |
Start the libcutl repository
Diffstat (limited to 'cutl/shared-ptr/base.cxx')
-rw-r--r-- | cutl/shared-ptr/base.cxx | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/cutl/shared-ptr/base.cxx b/cutl/shared-ptr/base.cxx new file mode 100644 index 0000000..a74ed15 --- /dev/null +++ b/cutl/shared-ptr/base.cxx @@ -0,0 +1,63 @@ +// file : cutl/shared-ptr/base.cxx +// author : Boris Kolpackov <boris@codesynthesis.com> +// copyright : Copyright (c) 2009 Code Synthesis Tools CC +// license : MIT; see accompanying LICENSE file + +#include <cutl/shared-ptr/base.hxx> + +using std::size_t; + +// +// +cutl::share shared = cutl::share (1); +cutl::share exclusive = cutl::share (2); + +// +// +namespace cutl +{ + char const* not_shared:: + what () const throw () + { + return "object is not shared"; + } +} + +// +// +void* +operator new (size_t n, cutl::share s) throw (std::bad_alloc) +{ + if (s == shared) + { + // Here we need to make sure we don't break the alignment of the + // returned block. For that we need to know the maximum alignment + // of this platform. Twice the pointer size is a good guess for + // most platforms. + // + size_t* p = static_cast<size_t*> (operator new (n + 2 * sizeof (size_t))); + *p++ = 1; // Initial count. + *p++ = 0xDEADBEEF; // Signature. + return p; + } + else + return operator new (n); + +} + +void +operator delete (void* p, cutl::share s) throw () +{ + // This version of operator delete is only called when the c-tor + // fails. In this case there is no object and we can just free the + // memory. + // + if (s == shared) + { + size_t* sp = static_cast<size_t*> (p); + sp -= 2; + operator delete (sp); + } + else + operator delete (p); +} |