litex/software/libbase/libc.c

585 lines
12 KiB
C

/*
* Milkymist SoC (Software)
* Copyright (C) 2007, 2008, 2009, 2010, 2011 Sebastien Bourdeauducq
* Copyright (C) Linus Torvalds and Linux kernel developers
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <limits.h>
int errno;
/**
* strchr - Find the first occurrence of a character in a string
* @s: The string to be searched
* @c: The character to search for
*/
char *strchr(const char *s, int c)
{
for (; *s != (char)c; ++s)
if (*s == '\0')
return NULL;
return (char *)s;
}
/**
* strrchr - Find the last occurrence of a character in a string
* @s: The string to be searched
* @c: The character to search for
*/
char *strrchr(const char *s, int c)
{
const char *p = s + strlen(s);
do {
if (*p == (char)c)
return (char *)p;
} while (--p >= s);
return NULL;
}
/**
* strnchr - Find a character in a length limited string
* @s: The string to be searched
* @count: The number of characters to be searched
* @c: The character to search for
*/
char *strnchr(const char *s, size_t count, int c)
{
for (; count-- && *s != '\0'; ++s)
if (*s == (char)c)
return (char *)s;
return NULL;
}
/**
* strcpy - Copy a %NUL terminated string
* @dest: Where to copy the string to
* @src: Where to copy the string from
*/
char *strcpy(char *dest, const char *src)
{
char *tmp = dest;
while ((*dest++ = *src++) != '\0')
/* nothing */;
return tmp;
}
/**
* strncpy - Copy a length-limited, %NUL-terminated string
* @dest: Where to copy the string to
* @src: Where to copy the string from
* @count: The maximum number of bytes to copy
*
* The result is not %NUL-terminated if the source exceeds
* @count bytes.
*
* In the case where the length of @src is less than that of
* count, the remainder of @dest will be padded with %NUL.
*
*/
char *strncpy(char *dest, const char *src, size_t count)
{
char *tmp = dest;
while (count) {
if ((*tmp = *src) != 0)
src++;
tmp++;
count--;
}
return dest;
}
/**
* strcmp - Compare two strings
* @cs: One string
* @ct: Another string
*/
int strcmp(const char *cs, const char *ct)
{
signed char __res;
while (1) {
if ((__res = *cs - *ct++) != 0 || !*cs++)
break;
}
return __res;
}
/**
* strncmp - Compare two strings using the first characters only
* @cs: One string
* @ct: Another string
* @count: Number of characters
*/
int strncmp(const char *cs, const char *ct, size_t count)
{
signed char __res;
size_t n;
n = 0;
__res = 0;
while (n < count) {
if ((__res = *cs - *ct++) != 0 || !*cs++)
break;
n++;
}
return __res;
}
/**
* strlen - Find the length of a string
* @s: The string to be sized
*/
size_t strlen(const char *s)
{
const char *sc;
for (sc = s; *sc != '\0'; ++sc)
/* nothing */;
return sc - s;
}
/**
* strnlen - Find the length of a length-limited string
* @s: The string to be sized
* @count: The maximum number of bytes to search
*/
size_t strnlen(const char *s, size_t count)
{
const char *sc;
for (sc = s; count-- && *sc != '\0'; ++sc)
/* nothing */;
return sc - s;
}
/**
* memcmp - Compare two areas of memory
* @cs: One area of memory
* @ct: Another area of memory
* @count: The size of the area.
*/
int memcmp(const void *cs, const void *ct, size_t count)
{
const unsigned char *su1, *su2;
int res = 0;
for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
if ((res = *su1 - *su2) != 0)
break;
return res;
}
/**
* memset - Fill a region of memory with the given value
* @s: Pointer to the start of the area.
* @c: The byte to fill the area with
* @count: The size of the area.
*/
void *memset(void *s, int c, size_t count)
{
char *xs = s;
while (count--)
*xs++ = c;
return s;
}
/**
* memcpy - Copies one area of memory to another
* @dest: Destination
* @src: Source
* @n: The size to copy.
*/
void *memcpy(void *to, const void *from, size_t n)
{
void *xto = to;
size_t temp;
if(!n)
return xto;
if((long)to & 1) {
char *cto = to;
const char *cfrom = from;
*cto++ = *cfrom++;
to = cto;
from = cfrom;
n--;
}
if(n > 2 && (long)to & 2) {
short *sto = to;
const short *sfrom = from;
*sto++ = *sfrom++;
to = sto;
from = sfrom;
n -= 2;
}
temp = n >> 2;
if(temp) {
long *lto = to;
const long *lfrom = from;
for(; temp; temp--)
*lto++ = *lfrom++;
to = lto;
from = lfrom;
}
if(n & 2) {
short *sto = to;
const short *sfrom = from;
*sto++ = *sfrom++;
to = sto;
from = sfrom;
}
if(n & 1) {
char *cto = to;
const char *cfrom = from;
*cto = *cfrom;
}
return xto;
}
/**
* memmove - Copies one area of memory to another, overlap possible
* @dest: Destination
* @src: Source
* @n: The size to copy.
*/
void *memmove(void *dest, const void *src, size_t count)
{
char *tmp, *s;
if(dest <= src) {
tmp = (char *) dest;
s = (char *) src;
while(count--)
*tmp++ = *s++;
} else {
tmp = (char *)dest + count;
s = (char *)src + count;
while(count--)
*--tmp = *--s;
}
return dest;
}
/**
* strstr - Find the first substring in a %NUL terminated string
* @s1: The string to be searched
* @s2: The string to search for
*/
char *strstr(const char *s1, const char *s2)
{
size_t l1, l2;
l2 = strlen(s2);
if (!l2)
return (char *)s1;
l1 = strlen(s1);
while (l1 >= l2) {
l1--;
if (!memcmp(s1, s2, l2))
return (char *)s1;
s1++;
}
return NULL;
}
/**
* strtoul - convert a string to an unsigned long
* @nptr: The start of the string
* @endptr: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
*/
unsigned long strtoul(const char *nptr, char **endptr, int base)
{
unsigned long result = 0,value;
if (!base) {
base = 10;
if (*nptr == '0') {
base = 8;
nptr++;
if ((toupper(*nptr) == 'X') && isxdigit(nptr[1])) {
nptr++;
base = 16;
}
}
} else if (base == 16) {
if (nptr[0] == '0' && toupper(nptr[1]) == 'X')
nptr += 2;
}
while (isxdigit(*nptr) &&
(value = isdigit(*nptr) ? *nptr-'0' : toupper(*nptr)-'A'+10) < base) {
result = result*base + value;
nptr++;
}
if (endptr)
*endptr = (char *)nptr;
return result;
}
/**
* strtol - convert a string to a signed long
* @nptr: The start of the string
* @endptr: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
*/
long strtol(const char *nptr, char **endptr, int base)
{
if(*nptr=='-')
return -strtoul(nptr+1,endptr,base);
return strtoul(nptr,endptr,base);
}
int skip_atoi(const char **s)
{
int i=0;
while (isdigit(**s))
i = i*10 + *((*s)++) - '0';
return i;
}
char *number(char *buf, char *end, unsigned long num, int base, int size, int precision, int type)
{
char c,sign,tmp[66];
const char *digits;
static const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
static const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
int i;
digits = (type & PRINTF_LARGE) ? large_digits : small_digits;
if (type & PRINTF_LEFT)
type &= ~PRINTF_ZEROPAD;
if (base < 2 || base > 36)
return NULL;
c = (type & PRINTF_ZEROPAD) ? '0' : ' ';
sign = 0;
if (type & PRINTF_SIGN) {
if ((signed long) num < 0) {
sign = '-';
num = - (signed long) num;
size--;
} else if (type & PRINTF_PLUS) {
sign = '+';
size--;
} else if (type & PRINTF_SPACE) {
sign = ' ';
size--;
}
}
if (type & PRINTF_SPECIAL) {
if (base == 16)
size -= 2;
else if (base == 8)
size--;
}
i = 0;
if (num == 0)
tmp[i++]='0';
else while (num != 0) {
tmp[i++] = digits[num % base];
num = num / base;
}
if (i > precision)
precision = i;
size -= precision;
if (!(type&(PRINTF_ZEROPAD+PRINTF_LEFT))) {
while(size-->0) {
if (buf < end)
*buf = ' ';
++buf;
}
}
if (sign) {
if (buf < end)
*buf = sign;
++buf;
}
if (type & PRINTF_SPECIAL) {
if (base==8) {
if (buf < end)
*buf = '0';
++buf;
} else if (base==16) {
if (buf < end)
*buf = '0';
++buf;
if (buf < end)
*buf = digits[33];
++buf;
}
}
if (!(type & PRINTF_LEFT)) {
while (size-- > 0) {
if (buf < end)
*buf = c;
++buf;
}
}
while (i < precision--) {
if (buf < end)
*buf = '0';
++buf;
}
while (i-- > 0) {
if (buf < end)
*buf = tmp[i];
++buf;
}
while (size-- > 0) {
if (buf < end)
*buf = ' ';
++buf;
}
return buf;
}
/**
* vscnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The return value is the number of characters which have been written into
* the @buf not including the trailing '\0'. If @size is <= 0 the function
* returns 0.
*
* Call this function if you are already dealing with a va_list.
* You probably want scnprintf() instead.
*/
int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
int i;
i=vsnprintf(buf,size,fmt,args);
return (i >= size) ? (size - 1) : i;
}
/**
* snprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The return value is the number of characters which would be
* generated for the given input, excluding the trailing null,
* as per ISO C99. If the return is greater than or equal to
* @size, the resulting string is truncated.
*/
int snprintf(char * buf, size_t size, const char *fmt, ...)
{
va_list args;
int i;
va_start(args, fmt);
i=vsnprintf(buf,size,fmt,args);
va_end(args);
return i;
}
/**
* scnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The return value is the number of characters written into @buf not including
* the trailing '\0'. If @size is <= 0 the function returns 0.
*/
int scnprintf(char * buf, size_t size, const char *fmt, ...)
{
va_list args;
int i;
va_start(args, fmt);
i = vsnprintf(buf, size, fmt, args);
va_end(args);
return (i >= size) ? (size - 1) : i;
}
/**
* vsprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The function returns the number of characters written
* into @buf. Use vsnprintf() or vscnprintf() in order to avoid
* buffer overflows.
*
* Call this function if you are already dealing with a va_list.
* You probably want sprintf() instead.
*/
int vsprintf(char *buf, const char *fmt, va_list args)
{
return vsnprintf(buf, INT_MAX, fmt, args);
}
/**
* sprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The function returns the number of characters written
* into @buf. Use snprintf() or scnprintf() in order to avoid
* buffer overflows.
*/
int sprintf(char * buf, const char *fmt, ...)
{
va_list args;
int i;
va_start(args, fmt);
i=vsnprintf(buf, INT_MAX, fmt, args);
va_end(args);
return i;
}
/**
* rand - Returns a pseudo random number
*/
static unsigned int randseed;
unsigned int rand(void)
{
randseed = 129 * randseed + 907633385;
return randseed;
}
void srand(unsigned int seed)
{
randseed = seed;
}
void abort(void)
{
printf("Aborted.");
while(1);
}