Infrastructure: Split the files into subdirectories.

[mLib] / mem / arena.h

diff --git a/mem/arena.h b/mem/arena.h
new file mode 100644 (file)
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--- /dev/null
+++ b/mem/arena.h
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+/* -*-c-*-
+ *
+ * Abstraction for memory allocation arenas
+ *
+ * (c) 2000 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of the mLib utilities library.
+ *
+ * mLib is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * mLib 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 Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with mLib; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#ifndef MLIB_ARENA_H
+#define MLIB_ARENA_H
+
+#ifdef __cplusplus
+  extern "C" {
+#endif
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <stdlib.h>
+
+/*----- Data structures ---------------------------------------------------*/
+
+/* --- An arena structure --- */
+
+typedef struct arena {
+  const struct arena_ops *ops;
+} arena;
+
+typedef struct arena_ops {
+  void *(*alloc)(arena */*a*/, size_t /*sz*/);
+  void *(*realloc)(arena */*a*/, void */*p*/, size_t /*sz*/, size_t /*osz*/);
+  void (*free)(arena */*a*/, void */*p*/);
+  void (*purge)(arena */*a*/);
+} arena_ops;
+
+/*----- Global variables --------------------------------------------------*/
+
+extern arena *arena_global;            /* Standard global arena */
+extern arena arena_stdlib;             /* Arena based on @malloc@/@free@ */
+
+/*----- Functions provided ------------------------------------------------*/
+
+/* --- @arena_fakerealloc@ --- *
+ *
+ * Arguments:  @arena *a@ = pointer to arena block
+ *             @void *p@ = pointer to memory block to resize
+ *             @size_t sz@ = size desired for the block
+ *             @size_t osz@ = size of the old block
+ *
+ * Returns:    ---
+ *
+ * Use:                Standard fake @realloc@ function, for use if you don't
+ *             support @realloc@ properly.
+ */
+
+extern void *arena_fakerealloc(arena */*a*/, void */*p*/,
+                              size_t /*sz*/, size_t /*osz*/);
+
+/* --- Useful macros --- */
+
+#define A_ALLOC(a, sz) (((a)->ops->alloc)((a), (sz)))
+#define A_REALLOC(a, p, sz, osz) (((a)->ops->realloc)((a), (p), (sz), (osz)))
+#define A_FREE(a, p) (((a)->ops->free)((a), (p)))
+
+/* --- Simple function equivalents --- */
+
+extern void *a_alloc(arena */*a*/, size_t /*sz*/);
+extern void *a_realloc(arena */*a*/, void */*p*/,
+                      size_t /*sz*/, size_t /*osz*/);
+extern void a_free(arena */*a*/, void */*p*/);
+
+/*----- That's all, folks -------------------------------------------------*/
+
+#ifdef __cplusplus
+  }
+#endif
+
+#endif