lbnmem.c
上传用户:zbbssh
上传日期:2007-01-08
资源大小:196k
文件大小:3k
- /*
- * lbnmem.c - low-level bignum memory handling.
- *
- * Copyright (c) 1995 Colin Plumb. All rights reserved.
- * For licensing and other legal details, see the file legal.c.
- *
- * Note that in all cases, the pointers passed around
- * are pointers to the *least* significant end of the word.
- * On big-endian machines, these are pointers to the *end*
- * of the allocated range.
- *
- * BNSECURE is a simple level of security; for more security
- * change these function to use locked unswappable memory.
- */
- #if HAVE_CONFIG_H
- #include "config.h"
- #endif
- #if HAVE_STDLIB_H
- #include <stdlib.h> /* For malloc() & co. */
- #else
- void *malloc();
- void free();
- #endif
- #if HAVE_STRING_H
- #include <string.h> /* For memset */
- #elif HAVE_STRINGS_H
- #include <strings.h>
- #endif
- #if NEED_MEMORY_H
- #include <memory.h>
- #endif
- #if DBMALLOC
- /* Development debugging */
- #include "../dbmalloc/malloc.h"
- #endif
- #include "lbn.h"
- #include "lbnmem.h"
- #include "kludge.h"
- #ifndef lbnMemWipe
- void
- lbnMemWipe(void *ptr, unsigned bytes)
- {
- memset(ptr, 0, bytes);
- }
- #define lbnMemWipe(ptr, bytes) memset(ptr, 0, bytes)
- #endif
- #ifndef lbnMemAlloc
- void *
- lbnMemAlloc(unsigned bytes)
- {
- return malloc(bytes);
- }
- #define lbnMemAlloc(bytes) malloc(bytes)
- #endif
- #ifndef lbnMemFree
- void
- lbnMemFree(void *ptr, unsigned bytes)
- {
- lbnMemWipe(ptr, bytes);
- free(ptr);
- }
- #endif
- #ifndef lbnRealloc
- #if defined(lbnMemRealloc) || !BNSECURE
- void *
- lbnRealloc(void *ptr, unsigned oldbytes, unsigned newbytes)
- {
- if (ptr) {
- BIG(ptr = (char *)ptr - oldbytes;)
- if (newbytes < oldbytes)
- memmove(ptr, (char *)ptr + oldbytes-newbytes, oldbytes);
- }
- #ifdef lbnMemRealloc
- ptr = lbnMemRealloc(ptr, oldbytes, newbytes);
- #else
- ptr = realloc(ptr, newbytes);
- #endif
- if (ptr) {
- if (newbytes > oldbytes)
- memmove((char *)ptr + newbytes-oldbytes, ptr, oldbytes);
- BIG(ptr = (char *)ptr + newbytes;)
- }
- return ptr;
- }
- #else /* BNSECURE */
- void *
- lbnRealloc(void *ptr, unsigned oldbytes, unsigned newbytes)
- {
- void *new = lbnMemAlloc(newbytes);
- if (!new)
- return new;
- if (!ptr)
- return BIGLITTLE((char *)new+newbytes, new);
- /*
- * The following copies are a bit non-obvious in the big-endian case
- * because one of the pointers points to the *end* of allocated memory.
- */
- if (newbytes > oldbytes) { /* Copy all of old into part of new */
- BIG(new = (char *)new + newbytes;)
- BIG(ptr = (char *)ptr - oldbytes;)
- memcpy(BIGLITTLE((char *)new-oldbytes, new), ptr, oldbytes);
- } else { /* Copy part of old into all of new */
- memcpy(new, BIGLITTLE((char *)ptr-newbytes, ptr), newbytes);
- BIG(new = (char *)new + newbytes;)
- BIG(ptr = (char *)ptr - oldbytes;)
- }
- lbnMemFree(ptr, oldbytes);
- return new;
- }
- #endif /* BNSECURE */
- #endif /* !lbnRealloc */