From 2d80409b226afeaff1bf69e3e18ab83f5e0eaf1f Mon Sep 17 00:00:00 2001 From: "mostang.com!davidm" Date: Thu, 19 Dec 2002 07:16:50 +0000 Subject: [PATCH] Rename: src/mempool.h -> include/mempool.h (Logical change 1.32) --- include/mempool.h | 88 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) diff --git a/include/mempool.h b/include/mempool.h index e69de29b..9617b2bf 100644 --- a/include/mempool.h +++ b/include/mempool.h @@ -0,0 +1,88 @@ +/* libunwind - a platform-independent unwind library + Copyright (C) 2002 Hewlett-Packard Co + Contributed by David Mosberger-Tang + +This file is part of libunwind. + +Permission is hereby granted, free of charge, to any person obtaining +a copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be +included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE +LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ + +#ifndef mempool_h +#define mempool_h + +/* Memory pools provide simple memory management of fixed-size + objects. Memory pools are used for two purposes: + + o To ensure a stack can be unwound even when a process + is out of memory. + + o To ensure a stack can be unwound at any time in a + multi-threaded process (e.g., even at a time when the normal + malloc-lock is taken, possibly by the very thread that is + being unwind). + + + To achieve the second objective, memory pools allocate memory + directly via mmap() system call (or an equivalent facility). + + The first objective is accomplished by reserving memory ahead of + time. Since the memory requirements of stack unwinding generally + depends on the complexity of the procedures being unwind, there is + no absolute guarantee that unwinding will always work, but in + practice, this should not be a serious problem. */ + +#include + +#define IPREFIX UNW_PASTE(_UI,UNW_TARGET) +#define sos_alloc(s) UNW_PASTE(IPREFIX, _sos_alloc)(s) +#define sos_free(p) UNW_PASTE(IPREFIX, _sos_free)(p) +#define mempool_init(p,s,r) UNW_PASTE(IPREFIX, _mempool_init)(p,s,r) +#define mempool_alloc(p) UNW_PASTE(IPREFIX, _mempool_alloc)(p) +#define mempool_free(p,o) UNW_PASTE(IPREFIX, _mempool_free)(p,o) + +/* The mempool structure should be treated as an opaque object. It's + declared here only to enable static allocation of mempools. */ +struct mempool + { + size_t obj_size; /* object size (rounded up for alignment) */ + unsigned int reserve; /* minimum (desired) size of the free-list */ + size_t chunk_size; /* allocation granularity */ + unsigned int num_free; /* number of objects on the free-list */ + struct object + { + struct object *next; + } + *free_list; + }; + +/* Emergency allocation for one-time stuff that doesn't fit the memory + pool model. */ +extern void *sos_alloc (size_t size); +extern void sos_free (void *ptr); + +/* Initialize POOL for an object size of OBJECT_SIZE bytes. RESERVE + is the number of objects that should be reserved for use under + tight memory situations. If it is zero, mempool attempts to pick a + reasonable default value. */ +extern void mempool_init (struct mempool *pool, + size_t obj_size, size_t reserve); +extern void *mempool_alloc (struct mempool *pool); +extern void mempool_free (struct mempool *pool, void *object); + +#endif /* mempool_h */