Merge branch 'dfsg-orig'

[debian/gnuradio] / gruel / src / include / gruel / pmt_pool.h

diff --git a/gruel/src/include/gruel/pmt_pool.h b/gruel/src/include/gruel/pmt_pool.h
new file mode 100644 (file)
index 0000000..b792523
--- /dev/null
+++ b/gruel/src/include/gruel/pmt_pool.h
@@ -0,0 +1,72 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007,2009 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#ifndef INCLUDED_PMT_POOL_H
+#define INCLUDED_PMT_POOL_H
+
+#include <cstddef>
+#include <vector>
+#include <boost/thread.hpp>
+
+namespace pmt {
+
+/*!
+ * \brief very simple thread-safe fixed-size allocation pool
+ *
+ * FIXME may want to go to global allocation with per-thread free list.
+ * This would eliminate virtually all lock contention.
+ */
+class pmt_pool {
+
+  struct item {
+    struct item        *d_next;
+  };
+  
+  typedef boost::unique_lock<boost::mutex>  scoped_lock;
+  mutable boost::mutex                 d_mutex;
+  boost::condition_variable    d_cond;
+  
+  size_t             d_itemsize;
+  size_t             d_alignment;
+  size_t             d_allocation_size;
+  size_t             d_max_items;
+  size_t             d_n_items;
+  item              *d_freelist;
+  std::vector<char *> d_allocations;
+
+public:
+  /*!
+   * \param itemsize size in bytes of the items to be allocated.
+   * \param alignment alignment in bytes of all objects to be allocated (must be power-of-2).
+   * \param allocation_size number of bytes to allocate at a time from the underlying allocator.
+   * \param max_items is the maximum number of items to allocate.  If this number is exceeded,
+   *         the allocate blocks.  0 implies no limit.
+   */
+  pmt_pool(size_t itemsize, size_t alignment = 16,
+          size_t allocation_size = 4096, size_t max_items = 0);
+  ~pmt_pool();
+
+  void *malloc();
+  void free(void *p);
+};
+
+} /* namespace pmt */
+
+#endif /* INCLUDED_PMT_POOL_H */