Merge branch 'upstream' into dfsg-orig

[debian/gnuradio] / gruel / src / lib / pmt / pmt_pool.cc

diff --git a/gruel/src/lib/pmt/pmt_pool.cc b/gruel/src/lib/pmt/pmt_pool.cc
new file mode 100644 (file)
index 0000000..731d28c
--- /dev/null
+++ b/gruel/src/lib/pmt/pmt_pool.cc
@@ -0,0 +1,112 @@
+/* -*- 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <gruel/pmt_pool.h>
+#include <algorithm>
+#include <stdint.h>
+
+namespace pmt {
+
+static inline size_t
+ROUNDUP(size_t x, size_t stride)
+{
+  return ((((x) + (stride) - 1)/(stride)) * (stride));
+}
+
+pmt_pool::pmt_pool(size_t itemsize, size_t alignment,
+                  size_t allocation_size, size_t max_items)
+  : d_itemsize(ROUNDUP(itemsize, alignment)),
+    d_alignment(alignment),
+    d_allocation_size(std::max(allocation_size, 16 * itemsize)),
+    d_max_items(max_items), d_n_items(0),
+    d_freelist(0)
+{
+}
+
+pmt_pool::~pmt_pool()
+{
+  for (unsigned int i = 0; i < d_allocations.size(); i++){
+    delete [] d_allocations[i];
+  }
+}
+
+void *
+pmt_pool::malloc()
+{
+  scoped_lock guard(d_mutex);
+  item *p;
+
+  if (d_max_items != 0){
+    while (d_n_items >= d_max_items)
+      d_cond.wait(guard);
+  }
+
+  if (d_freelist){     // got something?
+    p = d_freelist;
+    d_freelist = p->d_next;
+    d_n_items++;
+    return p;
+  }
+
+  // allocate a new chunk
+  char *alloc = new char[d_allocation_size + d_alignment - 1];
+  d_allocations.push_back(alloc);
+
+  // get the alignment we require
+  char *start = (char *)(((uintptr_t)alloc + d_alignment-1) & -d_alignment);
+  char *end = alloc + d_allocation_size + d_alignment - 1;
+  size_t n = (end - start) / d_itemsize;
+
+  // link the new items onto the free list.
+  p = (item *) start;
+  for (size_t i = 0; i < n; i++){
+    p->d_next = d_freelist;
+    d_freelist = p;
+    p = (item *)((char *) p + d_itemsize);
+  }
+
+  // now return the first one
+  p = d_freelist;
+  d_freelist = p->d_next;
+  d_n_items++;
+  return p;
+}
+
+void
+pmt_pool::free(void *foo)
+{
+  if (!foo)
+    return;
+
+  scoped_lock guard(d_mutex);
+
+  item *p = (item *) foo;
+  p->d_next = d_freelist;
+  d_freelist = p;
+  d_n_items--;
+  if (d_max_items != 0)
+    d_cond.notify_one();
+}
+
+} /* namespace pmt */