mirror of
https://github.com/obgm/libcoap.git
synced 2026-11-01 23:45:48 +03:00
Carsten Schoenert
0e59edc231
Resume the cleaning of the public header files, no functional changes. Reformatting the infos in the head of the header files, restructure header inclusion check to be more generic. Reorder some include directives in a alphabetical order. Remove including instructions for C++ stuff, it's already done in the coap.h header, and the user only has to include this header file. Dropping the prefixing of the include guarding of uthash.h because it would cause trouble with the macro handling in TinyDLS. Thanks Olaf for reminding this!
85 lines
1.7 KiB
C
85 lines
1.7 KiB
C
/*
|
|
* prng.h -- Pseudo Random Numbers
|
|
*
|
|
* Copyright (C) 2010-2011 Olaf Bergmann <bergmann@tzi.org>
|
|
*
|
|
* This file is part of the CoAP library libcoap. Please see README for terms
|
|
* of use.
|
|
*/
|
|
|
|
/**
|
|
* @file prng.h
|
|
* @brief Pseudo Random Numbers
|
|
*/
|
|
|
|
#ifndef _COAP_PRNG_H_
|
|
#define _COAP_PRNG_H_
|
|
|
|
/**
|
|
* @defgroup prng Pseudo Random Numbers
|
|
* @{
|
|
*/
|
|
|
|
#ifndef WITH_CONTIKI
|
|
#include <stdlib.h>
|
|
|
|
/**
|
|
* Fills \p buf with \p len random bytes. This is the default implementation for
|
|
* prng(). You might want to change prng() to use a better PRNG on your specific
|
|
* platform.
|
|
*/
|
|
static inline int
|
|
coap_prng_impl(unsigned char *buf, size_t len) {
|
|
while (len--)
|
|
*buf++ = rand() & 0xFF;
|
|
return 1;
|
|
}
|
|
#else /* WITH_CONTIKI */
|
|
#include <string.h>
|
|
|
|
/**
|
|
* Fills \p buf with \p len random bytes. This is the default implementation for
|
|
* prng(). You might want to change prng() to use a better PRNG on your specific
|
|
* platform.
|
|
*/
|
|
static inline int
|
|
contiki_prng_impl(unsigned char *buf, size_t len) {
|
|
unsigned short v = random_rand();
|
|
while (len > sizeof(v)) {
|
|
memcpy(buf, &v, sizeof(v));
|
|
len -= sizeof(v);
|
|
buf += sizeof(v);
|
|
v = random_rand();
|
|
}
|
|
|
|
memcpy(buf, &v, len);
|
|
return 1;
|
|
}
|
|
|
|
#define prng(Buf,Length) contiki_prng_impl((Buf), (Length))
|
|
#define prng_init(Value) random_init((unsigned short)(Value))
|
|
#endif /* WITH_CONTIKI */
|
|
|
|
#ifndef prng
|
|
/**
|
|
* Fills \p Buf with \p Length bytes of random data.
|
|
*
|
|
* @hideinitializer
|
|
*/
|
|
#define prng(Buf,Length) coap_prng_impl((Buf), (Length))
|
|
#endif
|
|
|
|
#ifndef prng_init
|
|
/**
|
|
* Called to set the PRNG seed. You may want to re-define this to allow for a
|
|
* better PRNG.
|
|
*
|
|
* @hideinitializer
|
|
*/
|
|
#define prng_init(Value) srand((unsigned long)(Value))
|
|
#endif
|
|
|
|
/** @} */
|
|
|
|
#endif /* _COAP_PRNG_H_ */
|