Initial revision

From-SVN: r14877

1 files changed, 121 insertions, 0 deletions

diff --git a/libstdc++/stl/tempbuf.h b/libstdc++/stl/tempbuf.h
new file mode 100644
index 0000000..18d9952
--- /dev/null
+++ b/libstdc++/stl/tempbuf.h
@@ -0,0 +1,121 @@
+/*
+ *
+ * Copyright (c) 1994
+ * Hewlett-Packard Company
+ *
+ * Permission to use, copy, modify, distribute and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appear in all copies and
+ * that both that copyright notice and this permission notice appear
+ * in supporting documentation.  Hewlett-Packard Company makes no
+ * representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied warranty.
+ *
+ *
+ * Copyright (c) 1996
+ * Silicon Graphics Computer Systems, Inc.
+ *
+ * Permission to use, copy, modify, distribute and sell this software
+ * and its documentation for any purpose is hereby granted without fee,
+ * provided that the above copyright notice appear in all copies and
+ * that both that copyright notice and this permission notice appear
+ * in supporting documentation.  Silicon Graphics makes no
+ * representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied warranty.
+ */
+
+#ifndef __SGI_STL_TEMPBUF_H
+#define __SGI_STL_TEMPBUF_H
+
+#include <limits.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <pair.h>
+#include <type_traits.h>
+
+template <class T>
+pair<T*, ptrdiff_t> get_temporary_buffer(ptrdiff_t len, T*) {
+  if (len > ptrdiff_t(INT_MAX / sizeof(T)))
+    len = INT_MAX / sizeof(T);
+
+  while (len > 0) {
+    T* tmp = (T*) malloc((size_t)len * sizeof(T));
+    if (tmp != 0)
+      return pair<T*, ptrdiff_t>(tmp, len);
+    len /= 2;
+  }
+
+  return pair<T*, ptrdiff_t>((T*)0, 0);
+}
+
+template <class T>
+void return_temporary_buffer(T* p) {
+  free(p);
+}
+
+template <class ForwardIterator,
+          class T /* = iterator_traits<ForwardIterator>::value_type */>
+class temporary_buffer {
+private:
+  ptrdiff_t original_len;
+  ptrdiff_t len;
+  T* buffer;
+
+  void allocate_buffer() {
+    original_len = len;
+    buffer = 0;
+
+    if (len > (ptrdiff_t)(INT_MAX / sizeof(T)))
+      len = INT_MAX / sizeof(T);
+
+    while (len > 0) {
+      buffer = (T*) malloc(len * sizeof(T));
+      if (buffer)
+        break;
+      len /= 2;
+    }
+  }
+
+  void initialize_buffer(const T&, __true_type) {}
+  void initialize_buffer(const T& val, __false_type) {
+    uninitialized_fill_n(buffer, len, val);
+  }
+
+public:
+  ptrdiff_t size() const { return len; }
+  ptrdiff_t requested_size() const { return original_len; }
+  T* begin() { return buffer; }
+  T* end() { return buffer + len; }
+
+  temporary_buffer(ForwardIterator first, ForwardIterator last) {
+#ifdef __STL_USE_EXCEPTIONS
+    try {
+#endif      
+      len = 0;
+      distance(first, last, len);
+      allocate_buffer();
+      if (len > 0)
+        initialize_buffer(*first,
+                          __type_traits<T>::has_trivial_default_constructor());
+#ifdef __STL_USE_EXCEPTIONS
+    }
+    catch(...) {
+      free(buffer);
+      buffer = 0;
+      len = 0;
+      throw;
+    }
+#endif      
+  }
+ 
+  ~temporary_buffer() {  
+    destroy(buffer, buffer + len);
+    free(buffer);
+  }
+
+private:
+  temporary_buffer(const temporary_buffer&) {}
+  void operator=(const temporary_buffer&) {}
+};
+
+#endif /* __SGI_STL_TEMPBUF_H */