string.c

minimal python variant for small footprint apps like embedded apps

/*
 *  linux/lib/string.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

/*
 * stupid library routines.. The optimized versions should generally be found
 * as inline code in <asm-xx/string.h>
 *
 * These are buggy as well..
 */

/* Adapted for the use in the 332 kernel 
 * D. Jeff Dionne, 1995.
 */

/* Additional hole filled: strtol
 * M. Schlifer, NOV 1995.
*/

#include <sys/types.h>
#include <string.h>
#include <ctype.h>

char * ___strtok = NULL;

#ifndef __HAVE_ARCH_STRTOUL
unsigned long strtoul(const char *cp,char **endp,unsigned int base)
{
  unsigned long result = 0,value;
  
  if (!base) {
    base = 10;
    if (*cp == '0') {
      base = 8;
      cp++;
      if ((*cp == 'x') && isxdigit(cp[1])) {
	cp++;
	base = 16;
      }
    }
  }
  while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp) ? toupper(*cp) : *cp)-'A'+10) < base) {
    result = result*base + value;
    cp++;
  }
  if (endp)
    *endp = (char *)cp;
  return result;
}
#endif

#ifndef __HAVE_ARCH_STRTOL
signed long strtol(const char *cp,char **endp,unsigned int base)
{
  signed long sign;
  signed long result = 0,value;
  if (!isdigit(*cp))
    {
      if ((*cp) == '-')
	sign = -1;
      else
	sign = 1;
      cp++;
    }
  else sign = 1;
  if (!base) {
    base = 10;
    if (*cp == '0') {
      base = 8;
      cp++;
      if ((*cp == 'x') && isxdigit(cp[1])) {
	cp++;
	base = 16;
      }
    }
  }
  while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
							     ? toupper(*cp) : *cp)-'A'+10) < base) {
    result = result*base + value;
    cp++;
  }
  if (endp)
    *endp = (char *)cp;
  return (result * sign);
}
#endif

#ifndef __HAVE_ARCH_STRCPY
char * strcpy(char * dest,const char *src)
{
  char *tmp = dest;
  
  while ((*dest++ = *src++) != '\0')
    /* nothing */;
  return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRNCPY
char * strncpy(char * dest,const char *src,size_t count)
{
  char *tmp = dest;
  
  while (count-- && (*dest++ = *src++) != '\0')
    /* nothing */;
  
  return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRCAT
char * strcat(char * dest, const char * src)
{
  char *tmp = dest;
  
  while (*dest)
    dest++;
  while ((*dest++ = *src++) != '\0');

  return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRNCAT
char * strncat(char *dest, const char *src, size_t count)
{
  char *tmp = dest;
  
  if (count) {
    while (*dest)
      dest++;
    while ((*dest++ = *src++)) {
      if (--count == 0)
	break;
    }
  }
  
  return tmp;
}
#endif

#ifndef __HAVE_ARCH_STRCMP
int strcmp(const char * cs,const char * ct)
{
  register signed char __res;
  
  while (1) {
    if ((__res = *cs - *ct++) != 0 || !*cs++)
      break;
  }
  
  return __res;
}
#endif

#ifndef __HAVE_ARCH_STRNCMP
int strncmp(const char * cs,const char * ct,size_t count)
{
  register signed char __res = 0;
  
  while (count) {
    if ((__res = *cs - *ct++) != 0 || !*cs++)
      break;
    count--;
  }
  
  return __res;
}
#endif

#ifndef __HAVE_ARCH_STRCHR
char * strchr(const char * s, int c)
{
  for(; *s != (char) c; ++s)
    if (*s == '\0')
      return NULL;
  return (char *) s;
}
#endif

#ifndef __HAVE_ARCH_STRLEN
size_t strlen(const char * s)
{
  const char *sc;
  
  for (sc = s; *sc != '\0'; ++sc)
    /* nothing */;
  return sc - s;
}
#endif

#ifndef __HAVE_ARCH_STRNLEN
size_t strnlen(const char * s, size_t count)
{
  const char *sc;
  
  for (sc = s; count-- && *sc != '\0'; ++sc)
    /* nothing */;
  return sc - s;
}
#endif

#ifndef __HAVE_ARCH_STRSPN
size_t strspn(const char *s, const char *accept)
{
  const char *p;
  const char *a;
  size_t count = 0;
  
  for (p = s; *p != '\0'; ++p) {
    for (a = accept; *a != '\0'; ++a) {
      if (*p == *a)
	break;
    }
    if (*a == '\0')
      return count;
    ++count;
  }

  return count;
}
#endif

#ifndef __HAVE_ARCH_STRPBRK
char * strpbrk(const char * cs,const char * ct)
{
  const char *sc1,*sc2;
  
  for( sc1 = cs; *sc1 != '\0'; ++sc1) {
    for( sc2 = ct; *sc2 != '\0'; ++sc2) {
      if (*sc1 == *sc2)
	return (char *) sc1;
    }
  }
  return NULL;
}
#endif

#ifndef __HAVE_ARCH_STRTOK
char * strtok(char * s,const char * ct)
{
  char *sbegin, *send;
  
  sbegin  = s ? s : ___strtok;
  if (!sbegin) {
    return NULL;
  }
  sbegin += strspn(sbegin,ct);
  if (*sbegin == '\0') {
    ___strtok = NULL;
    return( NULL );
  }
  send = strpbrk( sbegin, ct);
  if (send && *send != '\0')
    *send++ = '\0';
  ___strtok = send;
  return (sbegin);
}
#endif

#ifndef __HAVE_ARCH_MEMSET
void * memset(void * s,char c,size_t count)
{
  char *xs = (char *) s;

  while (count--)
    *xs++ = c;
  
  return s;
}
#endif

#ifndef __HAVE_ARCH_BCOPY
char * bcopy(const char * src, char * dest, int count)
{
  char *tmp = dest;
  
  while (count--)
    *tmp++ = *src++;
  
  return dest;
}
#endif

#ifndef __HAVE_ARCH_MEMCPY
void * memcpy(void * dest,const void *src,size_t count)
{
  char *tmp = (char *) dest, *s = (char *) src;
  
  while (count--)
    *tmp++ = *s++;
  
  return dest;
}
#endif

#ifndef __HAVE_ARCH_MEMMOVE
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;
}
#endif

#ifndef __HAVE_ARCH_MEMCMP
int memcmp(const void * cs,const void * ct,size_t count)
{
  const unsigned char *su1, *su2;
  signed char res = 0;
  
  for( su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
    if ((res = *su1 - *su2) != 0)
      break;
  return res;
}
#endif

/*
 * find the first occurrence of byte 'c', or 1 past the area if none
 */
#ifndef __HAVE_ARCH_MEMSCAN
void * memscan(void * addr, int c, size_t size)
{
  unsigned char * p = (unsigned char *) addr;

  while (size) {
    if (*p == c)
      return (void *) p;
    p++;
    size--;
  }
  return (void *) p;
}
#endif

#ifndef __HAVE_ARCH_STRSTR
char * strstr(const char * s1,const char * s2)
{
  int 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;
}
#endif