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authorpatacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3>2011-03-30 21:15:57 +0000
committerpatacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3>2011-03-30 21:15:57 +0000
commite503954f9899ad12f55646317e48fad4bf1cbfb2 (patch)
tree6fe69444df4b94dc4864a0b18358cddcb1e156f5 /nuttx/lib/stdlib
parent144c447139eb6739d67c01a446bf00826316f624 (diff)
downloadpx4-nuttx-e503954f9899ad12f55646317e48fad4bf1cbfb2.tar.gz
px4-nuttx-e503954f9899ad12f55646317e48fad4bf1cbfb2.tar.bz2
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Move more files into subdirectories under lib/
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3441 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/lib/stdlib')
-rw-r--r--nuttx/lib/stdlib/Make.defs36
-rw-r--r--nuttx/lib/stdlib/lib_abs.c54
-rw-r--r--nuttx/lib/stdlib/lib_imaxabs.c54
-rw-r--r--nuttx/lib/stdlib/lib_labs.c54
-rw-r--r--nuttx/lib/stdlib/lib_llabs.c57
-rw-r--r--nuttx/lib/stdlib/lib_qsort.c238
-rw-r--r--nuttx/lib/stdlib/lib_rand.c212
7 files changed, 705 insertions, 0 deletions
diff --git a/nuttx/lib/stdlib/Make.defs b/nuttx/lib/stdlib/Make.defs
new file mode 100644
index 000000000..42bf13bda
--- /dev/null
+++ b/nuttx/lib/stdlib/Make.defs
@@ -0,0 +1,36 @@
+############################################################################
+# lib/stdlib/Make.defs
+#
+# Copyright (C) 2011 Gregory Nutt. All rights reserved.
+# Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in
+# the documentation and/or other materials provided with the
+# distribution.
+# 3. Neither the name NuttX nor the names of its contributors may be
+# used to endorse or promote products derived from this software
+# without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+STDLIB_SRCS = lib_abs.c lib_imaxabs.c lib_labs.c lib_llabs.c lib_rand.c lib_qsort.c
diff --git a/nuttx/lib/stdlib/lib_abs.c b/nuttx/lib/stdlib/lib_abs.c
new file mode 100644
index 000000000..5c805d857
--- /dev/null
+++ b/nuttx/lib/stdlib/lib_abs.c
@@ -0,0 +1,54 @@
+/************************************************************************
+ * lib/stdlib/lib_abs.c
+ *
+ * Copyright (C) 2010-2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************************/
+
+/************************************************************************
+ * Included Files
+ ************************************************************************/
+
+#include <nuttx/config.h>
+#include <stdlib.h>
+
+/************************************************************************
+ * Global Functions
+ ************************************************************************/
+
+int abs(int j)
+{
+ if (j < 0)
+ {
+ j = -j;
+ }
+ return j;
+}
diff --git a/nuttx/lib/stdlib/lib_imaxabs.c b/nuttx/lib/stdlib/lib_imaxabs.c
new file mode 100644
index 000000000..d16791b26
--- /dev/null
+++ b/nuttx/lib/stdlib/lib_imaxabs.c
@@ -0,0 +1,54 @@
+/************************************************************************
+ * lib/stdlib//lib_abs.c
+ *
+ * Copyright (C) 2010-2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************************/
+
+/************************************************************************
+ * Included Files
+ ************************************************************************/
+
+#include <nuttx/config.h>
+#include <inttypes.h>
+
+/************************************************************************
+ * Global Functions
+ ************************************************************************/
+
+intmax_t imaxabs(intmax_t j)
+{
+ if (j < 0)
+ {
+ j = -j;
+ }
+ return j;
+}
diff --git a/nuttx/lib/stdlib/lib_labs.c b/nuttx/lib/stdlib/lib_labs.c
new file mode 100644
index 000000000..c9d9c1935
--- /dev/null
+++ b/nuttx/lib/stdlib/lib_labs.c
@@ -0,0 +1,54 @@
+/************************************************************************
+ * lib/stdlib/lib_labs.c
+ *
+ * Copyright (C) 2010-2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************************/
+
+/************************************************************************
+ * Included Files
+ ************************************************************************/
+
+#include <nuttx/config.h>
+#include <stdlib.h>
+
+/************************************************************************
+ * Global Functions
+ ************************************************************************/
+
+long int labs(long int j)
+{
+ if (j < 0)
+ {
+ j = -j;
+ }
+ return j;
+}
diff --git a/nuttx/lib/stdlib/lib_llabs.c b/nuttx/lib/stdlib/lib_llabs.c
new file mode 100644
index 000000000..24e26e9e1
--- /dev/null
+++ b/nuttx/lib/stdlib/lib_llabs.c
@@ -0,0 +1,57 @@
+/************************************************************************
+ * lib/stdlib/lib_llabs.c
+ *
+ * Copyright (C) 2010-2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************************/
+
+/************************************************************************
+ * Included Files
+ ************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/compiler.h>
+#include <stdlib.h>
+
+/************************************************************************
+ * Global Functions
+ ************************************************************************/
+
+#ifdef CONFIG_HAVE_LONG_LONG
+long long int llabs(long long int j)
+{
+ if (j < 0)
+ {
+ j = -j;
+ }
+ return j;
+}
+#endif
diff --git a/nuttx/lib/stdlib/lib_qsort.c b/nuttx/lib/stdlib/lib_qsort.c
new file mode 100644
index 000000000..13bca7499
--- /dev/null
+++ b/nuttx/lib/stdlib/lib_qsort.c
@@ -0,0 +1,238 @@
+/****************************************************************************
+ * lib/stdlib/lib_qsort.c
+ *
+ * Copyright (C) 2007, 2009, 2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Leveraged from:
+ *
+ * Copyright (c) 1992, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdlib.h>
+
+/****************************************************************************
+ * Preprocessor Definitions
+ ****************************************************************************/
+
+#define min(a, b) (a) < (b) ? a : b
+
+#define swapcode(TYPE, parmi, parmj, n) \
+ { \
+ long i = (n) / sizeof (TYPE); \
+ register TYPE *pi = (TYPE *) (parmi); \
+ register TYPE *pj = (TYPE *) (parmj); \
+ do { \
+ register TYPE t = *pi; \
+ *pi++ = *pj; \
+ *pj++ = t; \
+ } while (--i > 0); \
+ }
+
+#define SWAPINIT(a, size) \
+ swaptype = ((char *)a - (char *)0) % sizeof(long) || \
+ size % sizeof(long) ? 2 : size == sizeof(long)? 0 : 1;
+
+#define swap(a, b) \
+ if (swaptype == 0) \
+ { \
+ long t = *(long *)(a); \
+ *(long *)(a) = *(long *)(b); \
+ *(long *)(b) = t; \
+ } \
+ else \
+ { \
+ swapfunc(a, b, size, swaptype); \
+ }
+
+#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype)
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static inline void swapfunc(char *a, char *b, int n, int swaptype);
+static inline char *med3(char *a, char *b, char *c,
+ int (*compar)(const void *, const void *));
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+static inline void swapfunc(char *a, char *b, int n, int swaptype)
+{
+ if(swaptype <= 1)
+ {
+ swapcode(long, a, b, n)
+ }
+ else
+ {
+ swapcode(char, a, b, n)
+ }
+}
+
+static inline char *med3(char *a, char *b, char *c,
+ int (*compar)(const void *, const void *))
+{
+ return compar(a, b) < 0 ?
+ (compar(b, c) < 0 ? b : (compar(a, c) < 0 ? c : a ))
+ :(compar(b, c) > 0 ? b : (compar(a, c) < 0 ? a : c ));
+}
+
+/****************************************************************************
+ * Public Function
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: qsort
+ *
+ * Description:
+ * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
+ *
+ ****************************************************************************/
+
+void qsort(void *base, size_t nmemb, size_t size,
+ int(*compar)(const void *, const void *))
+{
+ char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
+ int d, r, swaptype, swap_cnt;
+
+loop:
+ SWAPINIT(base, size);
+ swap_cnt = 0;
+ if (nmemb < 7)
+ {
+ for (pm = (char *) base + size; pm < (char *) base + nmemb * size; pm += size)
+ {
+ for (pl = pm; pl > (char *) base && compar(pl - size, pl) > 0; pl -= size)
+ {
+ swap(pl, pl - size);
+ }
+ }
+ return;
+ }
+
+ pm = (char *) base + (nmemb / 2) * size;
+ if (nmemb > 7)
+ {
+ pl = base;
+ pn = (char *) base + (nmemb - 1) * size;
+ if (nmemb > 40)
+ {
+ d = (nmemb / 8) * size;
+ pl = med3(pl, pl + d, pl + 2 * d, compar);
+ pm = med3(pm - d, pm, pm + d, compar);
+ pn = med3(pn - 2 * d, pn - d, pn, compar);
+ }
+ pm = med3(pl, pm, pn, compar);
+ }
+ swap(base, pm);
+ pa = pb = (char *) base + size;
+
+ pc = pd = (char *) base + (nmemb - 1) * size;
+ for (;;)
+ {
+ while (pb <= pc && (r = compar(pb, base)) <= 0)
+ {
+ if (r == 0)
+ {
+ swap_cnt = 1;
+ swap(pa, pb);
+ pa += size;
+ }
+ pb += size;
+ }
+ while (pb <= pc && (r = compar(pc, base)) >= 0)
+ {
+ if (r == 0)
+ {
+ swap_cnt = 1;
+ swap(pc, pd);
+ pd -= size;
+ }
+ pc -= size;
+ }
+
+ if (pb > pc)
+ {
+ break;
+ }
+
+ swap(pb, pc);
+ swap_cnt = 1;
+ pb += size;
+ pc -= size;
+ }
+
+ if (swap_cnt == 0)
+ {
+ /* Switch to insertion sort */
+
+ for (pm = (char *) base + size; pm < (char *) base + nmemb * size; pm += size)
+ {
+ for (pl = pm; pl > (char *) base && compar(pl - size, pl) > 0; pl -= size)
+ {
+ swap(pl, pl - size);
+ }
+ }
+ return;
+ }
+
+ pn = (char *) base + nmemb * size;
+ r = min(pa - (char *)base, pb - pa);
+ vecswap(base, pb - r, r);
+ r = min(pd - pc, pn - pd - size);
+ vecswap(pb, pn - r, r);
+
+ if ((r = pb - pa) > size)
+ {
+ qsort(base, r / size, size, compar);
+ }
+
+ if ((r = pd - pc) > size)
+ {
+ /* Iterate rather than recurse to save stack space */
+ base = pn - r;
+ nmemb = r / size;
+ goto loop;
+ }
+}
+
diff --git a/nuttx/lib/stdlib/lib_rand.c b/nuttx/lib/stdlib/lib_rand.c
new file mode 100644
index 000000000..3f3b33d5f
--- /dev/null
+++ b/nuttx/lib/stdlib/lib_rand.c
@@ -0,0 +1,212 @@
+/************************************************************
+ * lib/stdlib/lib_rand.c
+ *
+ * Copyright (C) 2007,l 2011 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Compilation Switches
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <sys/types.h>
+#include <stdlib.h>
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+#ifndef RND_ORDER
+#define RND_ORDER 1
+#endif
+
+/* Values needed by the random number generator */
+
+#define RND1_CONSTK 470001
+#define RND1_CONSTP 999563
+#define RND2_CONSTK1 366528
+#define RND2_CONSTK2 508531
+#define RND2_CONSTP 998917
+#define RND3_CONSTK1 360137
+#define RND3_CONSTK2 519815
+#define RND3_CONSTK3 616087
+#define RND3_CONSTP 997783
+
+#if RND_ORDER == 1
+# define RND_CONSTP RND1_CONSTP
+#elif RND_ORDER == 2
+# define RND_CONSTP RND2_CONSTP
+#else
+# define RND_CONSTP RND3_CONSTP
+#endif
+
+/************************************************************
+ * Private Type Declarations
+ ************************************************************/
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+static unsigned int nrand(unsigned int nLimit);
+static double_t frand1(void);
+#if (RND_ORDER > 1)
+static double_t frand2(void);
+#if (RND_ORDER > 2)
+static double_t frand3(void);
+#endif
+#endif
+
+/**********************************************************
+ * Global Constant Data
+ **********************************************************/
+
+/************************************************************
+ * Global Variables
+ ************************************************************/
+
+/**********************************************************
+ * Private Constant Data
+ **********************************************************/
+
+/************************************************************
+ * Private Variables
+ ************************************************************/
+
+static unsigned long g_nRandInt1;
+#if (RND_ORDER > 1)
+static unsigned long g_nRandInt2;
+#if (RND_ORDER > 2)
+static unsigned long g_nRandInt3;
+#endif
+#endif
+
+/************************************************************
+ * Function: srand, rand
+ ************************************************************/
+
+void srand(unsigned int seed)
+{
+ g_nRandInt1 = seed;
+#if (RND_ORDER > 1)
+ g_nRandInt2 = seed;
+ (void)frand1();
+#if (RND_ORDER > 2)
+ g_nRandInt3 = seed;
+ (void)frand2();
+#endif
+#endif
+
+} /* end srand */
+
+int rand(void)
+{
+ return (int)nrand(32768);
+
+} /* end rand */
+
+static unsigned int nrand(unsigned int nLimit)
+{
+ unsigned long nResult;
+ double_t fRatio;
+
+ /* Loop to be sure a legal random number is generated */
+ do {
+
+ /* Get a random integer in the requested range */
+#if (RND_ORDER == 1)
+ fRatio = frand1();
+#elif (RND_ORDER == 2)
+ fRatio = frand2();
+#else
+ fRatio = frand3();
+#endif
+
+ /* Then, produce the return-able value */
+ nResult = (unsigned long)(((double_t)nLimit) * fRatio);
+
+ } while (nResult >= (unsigned long)nLimit);
+
+ return (unsigned int)nResult;
+
+} /* end nrand */
+
+static double_t frand1(void)
+{
+ unsigned long nRandInt;
+
+ /* First order congruential generator */
+ nRandInt = (RND1_CONSTK * g_nRandInt1) % RND1_CONSTP;
+ g_nRandInt1 = nRandInt;
+
+ /* Construct an floating point value in the range from 0.0 up to 1.0 */
+ return ((double_t)nRandInt) / ((double_t)RND_CONSTP);
+
+} /* end frand */
+
+#if (RND_ORDER > 1)
+static double_t frand2(void)
+{
+ unsigned long nRandInt;
+
+ /* Second order congruential generator */
+ nRandInt = (RND2_CONSTK1 * g_nRandInt1 + RND2_CONSTK2 * g_nRandInt2) %
+ RND2_CONSTP;
+ g_nRandInt2 = g_nRandInt1;
+ g_nRandInt1 = nRandInt;
+
+ /* Construct an floating point value in the range from 0.0 up to 1.0 */
+ return ((double_t)nRandInt) / ((double_t)RND_CONSTP);
+
+} /* end frand */
+
+#if (RND_ORDER > 2)
+static double_t frand(void)
+{
+ unsigned long nRandInt;
+
+ /* Third order congruential generator */
+ nRandInt = (RND3_CONSTK1 * g_nRandInt1 + RND3_CONSTK2 * g_nRandInt2 +
+ RND3_CONSTK2 * g_nRandInt3) % RND3_CONSTP;
+ g_nRandInt3 = g_nRandInt2;
+ g_nRandInt2 = g_nRandInt1;
+ g_nRandInt1 = nRandInt;
+
+ /* Construct an floating point value in the range from 0.0 up to 1.0 */
+ return ((double_t)nRandInt) / ((double_t)RND_CONSTP);
+
+} /* end frand */
+#endif
+#endif