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Added random, strdup, and strtok_r.

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This commit is contained in:
Philip Homburg 2005-07-11 13:06:27 +00:00
parent c60f3ff846
commit b5809b6a81
5 changed files with 609 additions and 0 deletions
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15
lib/other/Makefile
View file

@ -52,9 +52,12 @@ OBJECTS = \
$(LIBRARY)(popen.o) \
$(LIBRARY)(putenv.o) \
$(LIBRARY)(putw.o) \
$(LIBRARY)(random.o) \
$(LIBRARY)(setgroups.o) \
$(LIBRARY)(settimeofday.o) \
$(LIBRARY)(stderr.o) \
$(LIBRARY)(strdup.o) \
$(LIBRARY)(strtok_r.o) \
$(LIBRARY)(swab.o) \
$(LIBRARY)(syscall.o) \
$(LIBRARY)(sysconf.o) \
@ -210,6 +213,9 @@ $(LIBRARY)(putw.o): putw.c
$(LIBRARY)(rindex.o): rindex.c
$(CC1) rindex.c
$(LIBRARY)(random.o): random.c
$(CC1) random.c
$(LIBRARY)(setgroups.o): setgroups.c
$(CC1) setgroups.c
@ -219,6 +225,12 @@ $(LIBRARY)(settimeofday.o): settimeofday.c
$(LIBRARY)(stderr.o): stderr.c
$(CC1) stderr.c
$(LIBRARY)(strdup.o): strdup.c
$(CC1) strdup.c
$(LIBRARY)(strtok_r.o): strtok_r.c
$(CC1) strtok_r.c
$(LIBRARY)(swab.o): swab.c
$(CC1) swab.c
@ -248,3 +260,6 @@ $(LIBRARY)(v8regexp.o): v8regexp.c
$(LIBRARY)(v8regsub.o): v8regsub.c
$(CC1) v8regsub.c
$(LIBRARY)(writev.o): writev.c
$(CC1) writev.c

363
lib/other/random.c Normal file
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@ -0,0 +1,363 @@
/*
* Copyright (c) 1983, 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)random.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <stdio.h>
#include <stdlib.h>
/*
* random.c:
*
* An improved random number generation package. In addition to the standard
* rand()/srand() like interface, this package also has a special state info
* interface. The initstate() routine is called with a seed, an array of
* bytes, and a count of how many bytes are being passed in; this array is
* then initialized to contain information for random number generation with
* that much state information. Good sizes for the amount of state
* information are 32, 64, 128, and 256 bytes. The state can be switched by
* calling the setstate() routine with the same array as was initiallized
* with initstate(). By default, the package runs with 128 bytes of state
* information and generates far better random numbers than a linear
* congruential generator. If the amount of state information is less than
* 32 bytes, a simple linear congruential R.N.G. is used.
*
* Internally, the state information is treated as an array of longs; the
* zeroeth element of the array is the type of R.N.G. being used (small
* integer); the remainder of the array is the state information for the
* R.N.G. Thus, 32 bytes of state information will give 7 longs worth of
* state information, which will allow a degree seven polynomial. (Note:
* the zeroeth word of state information also has some other information
* stored in it -- see setstate() for details).
*
* The random number generation technique is a linear feedback shift register
* approach, employing trinomials (since there are fewer terms to sum up that
* way). In this approach, the least significant bit of all the numbers in
* the state table will act as a linear feedback shift register, and will
* have period 2^deg - 1 (where deg is the degree of the polynomial being
* used, assuming that the polynomial is irreducible and primitive). The
* higher order bits will have longer periods, since their values are also
* influenced by pseudo-random carries out of the lower bits. The total
* period of the generator is approximately deg*(2**deg - 1); thus doubling
* the amount of state information has a vast influence on the period of the
* generator. Note: the deg*(2**deg - 1) is an approximation only good for
* large deg, when the period of the shift register is the dominant factor.
* With deg equal to seven, the period is actually much longer than the
* 7*(2**7 - 1) predicted by this formula.
*/
/*
* For each of the currently supported random number generators, we have a
* break value on the amount of state information (you need at least this
* many bytes of state info to support this random number generator), a degree
* for the polynomial (actually a trinomial) that the R.N.G. is based on, and
* the separation between the two lower order coefficients of the trinomial.
*/
#define TYPE_0 0 /* linear congruential */
#define BREAK_0 8
#define DEG_0 0
#define SEP_0 0
#define TYPE_1 1 /* x**7 + x**3 + 1 */
#define BREAK_1 32
#define DEG_1 7
#define SEP_1 3
#define TYPE_2 2 /* x**15 + x + 1 */
#define BREAK_2 64
#define DEG_2 15
#define SEP_2 1
#define TYPE_3 3 /* x**31 + x**3 + 1 */
#define BREAK_3 128
#define DEG_3 31
#define SEP_3 3
#define TYPE_4 4 /* x**63 + x + 1 */
#define BREAK_4 256
#define DEG_4 63
#define SEP_4 1
/*
* Array versions of the above information to make code run faster --
* relies on fact that TYPE_i == i.
*/
#define MAX_TYPES 5 /* max number of types above */
static int degrees[MAX_TYPES] = { DEG_0, DEG_1, DEG_2, DEG_3, DEG_4 };
static int seps [MAX_TYPES] = { SEP_0, SEP_1, SEP_2, SEP_3, SEP_4 };
/*
* Initially, everything is set up as if from:
*
* initstate(1, &randtbl, 128);
*
* Note that this initialization takes advantage of the fact that srandom()
* advances the front and rear pointers 10*rand_deg times, and hence the
* rear pointer which starts at 0 will also end up at zero; thus the zeroeth
* element of the state information, which contains info about the current
* position of the rear pointer is just
*
* MAX_TYPES * (rptr - state) + TYPE_3 == TYPE_3.
*/
static long randtbl[DEG_3 + 1] = {
TYPE_3,
0x9a319039, 0x32d9c024, 0x9b663182, 0x5da1f342, 0xde3b81e0, 0xdf0a6fb5,
0xf103bc02, 0x48f340fb, 0x7449e56b, 0xbeb1dbb0, 0xab5c5918, 0x946554fd,
0x8c2e680f, 0xeb3d799f, 0xb11ee0b7, 0x2d436b86, 0xda672e2a, 0x1588ca88,
0xe369735d, 0x904f35f7, 0xd7158fd6, 0x6fa6f051, 0x616e6b96, 0xac94efdc,
0x36413f93, 0xc622c298, 0xf5a42ab8, 0x8a88d77b, 0xf5ad9d0e, 0x8999220b,
0x27fb47b9,
};
/*
* fptr and rptr are two pointers into the state info, a front and a rear
* pointer. These two pointers are always rand_sep places aparts, as they
* cycle cyclically through the state information. (Yes, this does mean we
* could get away with just one pointer, but the code for random() is more
* efficient this way). The pointers are left positioned as they would be
* from the call
*
* initstate(1, randtbl, 128);
*
* (The position of the rear pointer, rptr, is really 0 (as explained above
* in the initialization of randtbl) because the state table pointer is set
* to point to randtbl[1] (as explained below).
*/
static long *fptr = &randtbl[SEP_3 + 1];
static long *rptr = &randtbl[1];
/*
* The following things are the pointer to the state information table, the
* type of the current generator, the degree of the current polynomial being
* used, and the separation between the two pointers. Note that for efficiency
* of random(), we remember the first location of the state information, not
* the zeroeth. Hence it is valid to access state[-1], which is used to
* store the type of the R.N.G. Also, we remember the last location, since
* this is more efficient than indexing every time to find the address of
* the last element to see if the front and rear pointers have wrapped.
*/
static long *state = &randtbl[1];
static int rand_type = TYPE_3;
static int rand_deg = DEG_3;
static int rand_sep = SEP_3;
static long *end_ptr = &randtbl[DEG_3 + 1];
/*
* srandom:
*
* Initialize the random number generator based on the given seed. If the
* type is the trivial no-state-information type, just remember the seed.
* Otherwise, initializes state[] based on the given "seed" via a linear
* congruential generator. Then, the pointers are set to known locations
* that are exactly rand_sep places apart. Lastly, it cycles the state
* information a given number of times to get rid of any initial dependencies
* introduced by the L.C.R.N.G. Note that the initialization of randtbl[]
* for default usage relies on values produced by this routine.
*/
void
srandom(x)
u_int x;
{
register int i, j;
if (rand_type == TYPE_0)
state[0] = x;
else {
j = 1;
state[0] = x;
for (i = 1; i < rand_deg; i++)
state[i] = 1103515245 * state[i - 1] + 12345;
fptr = &state[rand_sep];
rptr = &state[0];
for (i = 0; i < 10 * rand_deg; i++)
(void)random();
}
}
/*
* initstate:
*
* Initialize the state information in the given array of n bytes for future
* random number generation. Based on the number of bytes we are given, and
* the break values for the different R.N.G.'s, we choose the best (largest)
* one we can and set things up for it. srandom() is then called to
* initialize the state information.
*
* Note that on return from srandom(), we set state[-1] to be the type
* multiplexed with the current value of the rear pointer; this is so
* successive calls to initstate() won't lose this information and will be
* able to restart with setstate().
*
* Note: the first thing we do is save the current state, if any, just like
* setstate() so that it doesn't matter when initstate is called.
*
* Returns a pointer to the old state.
*/
char *
initstate(seed, arg_state, n)
u_int seed; /* seed for R.N.G. */
char *arg_state; /* pointer to state array */
size_t n; /* # bytes of state info */
{
register char *ostate = (char *)(&state[-1]);
if (rand_type == TYPE_0)
state[-1] = rand_type;
else
state[-1] = MAX_TYPES * (rptr - state) + rand_type;
if (n < BREAK_0) {
(void)fprintf(stderr,
"random: not enough state (%d bytes); ignored.\n", n);
return(0);
}
if (n < BREAK_1) {
rand_type = TYPE_0;
rand_deg = DEG_0;
rand_sep = SEP_0;
} else if (n < BREAK_2) {
rand_type = TYPE_1;
rand_deg = DEG_1;
rand_sep = SEP_1;
} else if (n < BREAK_3) {
rand_type = TYPE_2;
rand_deg = DEG_2;
rand_sep = SEP_2;
} else if (n < BREAK_4) {
rand_type = TYPE_3;
rand_deg = DEG_3;
rand_sep = SEP_3;
} else {
rand_type = TYPE_4;
rand_deg = DEG_4;
rand_sep = SEP_4;
}
state = &(((long *)arg_state)[1]); /* first location */
end_ptr = &state[rand_deg]; /* must set end_ptr before srandom */
srandom(seed);
if (rand_type == TYPE_0)
state[-1] = rand_type;
else
state[-1] = MAX_TYPES*(rptr - state) + rand_type;
return(ostate);
}
/*
* setstate:
*
* Restore the state from the given state array.
*
* Note: it is important that we also remember the locations of the pointers
* in the current state information, and restore the locations of the pointers
* from the old state information. This is done by multiplexing the pointer
* location into the zeroeth word of the state information.
*
* Note that due to the order in which things are done, it is OK to call
* setstate() with the same state as the current state.
*
* Returns a pointer to the old state information.
*/
char *
setstate(arg_state)
const char *arg_state;
{
register long *new_state = (long *)arg_state;
register int type = new_state[0] % MAX_TYPES;
register int rear = new_state[0] / MAX_TYPES;
char *ostate = (char *)(&state[-1]);
if (rand_type == TYPE_0)
state[-1] = rand_type;
else
state[-1] = MAX_TYPES * (rptr - state) + rand_type;
switch(type) {
case TYPE_0:
case TYPE_1:
case TYPE_2:
case TYPE_3:
case TYPE_4:
rand_type = type;
rand_deg = degrees[type];
rand_sep = seps[type];
break;
default:
(void)fprintf(stderr,
"random: state info corrupted; not changed.\n");
}
state = &new_state[1];
if (rand_type != TYPE_0) {
rptr = &state[rear];
fptr = &state[(rear + rand_sep) % rand_deg];
}
end_ptr = &state[rand_deg]; /* set end_ptr too */
return(ostate);
}
/*
* random:
*
* If we are using the trivial TYPE_0 R.N.G., just do the old linear
* congruential bit. Otherwise, we do our fancy trinomial stuff, which is
* the same in all the other cases due to all the global variables that have
* been set up. The basic operation is to add the number at the rear pointer
* into the one at the front pointer. Then both pointers are advanced to
* the next location cyclically in the table. The value returned is the sum
* generated, reduced to 31 bits by throwing away the "least random" low bit.
*
* Note: the code takes advantage of the fact that both the front and
* rear pointers can't wrap on the same call by not testing the rear
* pointer if the front one has wrapped.
*
* Returns a 31-bit random number.
*/
long
random()
{
long i;
if (rand_type == TYPE_0)
i = state[0] = (state[0] * 1103515245 + 12345) & 0x7fffffff;
else {
*fptr += *rptr;
i = (*fptr >> 1) & 0x7fffffff; /* chucking least random bit */
if (++fptr >= end_ptr) {
fptr = state;
++rptr;
} else if (++rptr >= end_ptr)
rptr = state;
}
return(i);
}

23
lib/other/strdup.c Normal file
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@ -0,0 +1,23 @@
/*
lib/other/strdup.c
*/
#include <stdlib.h>
#include <string.h>
char *strdup(s1)
const char *s1;
{
size_t len;
char *s2;
len= strlen(s1)+1;
s2= malloc(len);
if (s2 == NULL)
return NULL;
strcpy(s2, s1);
return s2;
}

169
lib/other/strtok_r.c Normal file
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@ -0,0 +1,169 @@
/*
* Copyright (c) 1998 Softweyr LLC. All rights reserved.
*
* strtok_r, from Berkeley strtok
* Oct 13, 1998 by Wes Peters <wes@softweyr.com>
*
* Copyright (c) 1988, 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
* notices, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notices, 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 Softweyr LLC, 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 SOFTWEYR LLC, 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 SOFTWEYR LLC, 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.
*/
#ifndef lint
static const char rcsid[] =
"$FreeBSD: src/lib/libc/string/strtok.c,v 1.2.6.1 2001/07/09 23:30:07 obrien Exp $";
#endif
#include <stddef.h>
#include <string.h>
char *
strtok_r(char *s, const char *delim, char **last)
{
char *spanp;
int c, sc;
char *tok;
if (s == NULL && (s = *last) == NULL)
{
return NULL;
}
/*
* Skip (span) leading delimiters (s += strspn(s, delim), sort of).
*/
cont:
c = *s++;
for (spanp = (char *)delim; (sc = *spanp++) != 0; )
{
if (c == sc)
{
goto cont;
}
}
if (c == 0) /* no non-delimiter characters */
{
*last = NULL;
return NULL;
}
tok = s - 1;
/*
* Scan token (scan for delimiters: s += strcspn(s, delim), sort of).
* Note that delim must have one NUL; we stop if we see that, too.
*/
for (;;)
{
c = *s++;
spanp = (char *)delim;
do
{
if ((sc = *spanp++) == c)
{
if (c == 0)
{
s = NULL;
}
else
{
char *w = s - 1;
*w = '\0';
}
*last = s;
return tok;
}
}
while (sc != 0);
}
/* NOTREACHED */
}
#if 0
char *
strtok(char *s, const char *delim)
{
static char *last;
return strtok_r(s, delim, &last);
}
#endif
#if defined(DEBUG_STRTOK)
/*
* Test the tokenizer.
*/
int
main()
{
char test[80], blah[80];
char *sep = "\\/:;=-";
char *word, *phrase, *brkt, *brkb;
printf("String tokenizer test:\n");
strcpy(test, "This;is.a:test:of=the/string\\tokenizer-function.");
for (word = strtok(test, sep);
word;
word = strtok(NULL, sep))
{
printf("Next word is \"%s\".\n", word);
}
phrase = "foo";
strcpy(test, "This;is.a:test:of=the/string\\tokenizer-function.");
for (word = strtok_r(test, sep, &brkt);
word;
word = strtok_r(NULL, sep, &brkt))
{
strcpy(blah, "blah:blat:blab:blag");
for (phrase = strtok_r(blah, sep, &brkb);
phrase;
phrase = strtok_r(NULL, sep, &brkb))
{
printf("So far we're at %s:%s\n", word, phrase);
}
}
return 0;
}
#endif /* DEBUG_STRTOK */

39
lib/other/writev.c Normal file
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@ -0,0 +1,39 @@
#include <errno.h>
#include <stdio.h>
#include <sys/uio.h>
ssize_t writev(int fildes, const struct iovec *iov, int iovcnt)
{
#if DEBUG
fprintf(stderr, "bind: not implemented for fd %d\n", socket);
#endif
errno= ENOSYS;
return -1;
#if 0
int i, r;
char *p;
ssize_t l, sum;
/* We should buffer */
sum= 0;
for (i= 0; i<iovcnt; i++)
{
p= iov[i].iov_base;
l= iov[i].iov_len;
while (l > 0)
{
r= write(fildes, p, l);
if (r <= 0)
{
assert(sum == 0);
return r;
}
p += r;
l -= r;
sum += r;
}
}
return sum;
#endif
}