Non-standard functions

Collaboration diagram for Non-standard functions:

Functions
char *	lwip_strnstr (const char *buffer, const char *token, size_t n)
int	lwip_stricmp (const char *str1, const char *str2)
int	lwip_strnicmp (const char *str1, const char *str2, size_t len)
void	lwip_itoa (char *result, size_t bufsize, int number)

Detailed Description

lwIP provides default implementations for non-standard functions. These can be mapped to OS functions to reduce code footprint if desired. All defines related to this section must not be placed in lwipopts.h, but in arch/cc.h! These options cannot be #defined in lwipopts.h since they are not options of lwIP itself, but options of the lwIP port to your system.

Function Documentation

lwip_strnstr()

char* lwip_strnstr	(	const char *	buffer,
		const char *	token,
		size_t	n
	)

lwIP default implementation for strnstr() non-standard function. This can be #defined to strnstr() depending on your platform port.

{
  const char* p;
  size_t tokenlen = strlen(token);
  if (tokenlen == 0) {
    return LWIP_CONST_CAST(char *, buffer);
  }
  for (p = buffer; *p && (p + tokenlen <= buffer + n); p++) {
    if ((*p == *token) && (strncmp(p, token, tokenlen) == 0)) {
      return LWIP_CONST_CAST(char *, p);
    }
  }
  return NULL;
}

lwip_stricmp()

int lwip_stricmp	(	const char *	str1,
		const char *	str2
	)

lwIP default implementation for stricmp() non-standard function. This can be #defined to stricmp() depending on your platform port.

{
  char c1, c2;
 
  do {
    c1 = *str1++;
    c2 = *str2++;
    if (c1 != c2) {
      char c1_upc = c1 | 0x20;
      if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
        /* characters are not equal an one is in the alphabet range:
        downcase both chars and check again */
        char c2_upc = c2 | 0x20;
        if (c1_upc != c2_upc) {
          /* still not equal */
          /* don't care for < or > */
          return 1;
        }
      } else {
        /* characters are not equal but none is in the alphabet range */
        return 1;
      }
    }
  } while (c1 != 0);
  return 0;
}

lwip_strnicmp()

int lwip_strnicmp	(	const char *	str1,
		const char *	str2,
		size_t	len
	)

lwIP default implementation for strnicmp() non-standard function. This can be #defined to strnicmp() depending on your platform port.

{
  char c1, c2;
 
  do {
    c1 = *str1++;
    c2 = *str2++;
    if (c1 != c2) {
      char c1_upc = c1 | 0x20;
      if ((c1_upc >= 'a') && (c1_upc <= 'z')) {
        /* characters are not equal an one is in the alphabet range:
        downcase both chars and check again */
        char c2_upc = c2 | 0x20;
        if (c1_upc != c2_upc) {
          /* still not equal */
          /* don't care for < or > */
          return 1;
        }
      } else {
        /* characters are not equal but none is in the alphabet range */
        return 1;
      }
    }
  } while (len-- && c1 != 0);
  return 0;
}

lwip_itoa()

void lwip_itoa	(	char *	result,
		size_t	bufsize,
		int	number
	)

lwIP default implementation for itoa() non-standard function. This can be #defined to itoa() or snprintf(result, bufsize, "%d", number) depending on your platform port.

{
  const int base = 10;
  char* ptr = result, *ptr1 = result, tmp_char;
  int tmp_value;
  LWIP_UNUSED_ARG(bufsize);
 
  do {
    tmp_value = number;
    number /= base;
    *ptr++ = "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"[35 + (tmp_value - number * base)];
  } while(number);
 
   /* Apply negative sign */
  if (tmp_value < 0) {
     *ptr++ = '-';
  }
  *ptr-- = '\0';
  while(ptr1 < ptr) {
    tmp_char = *ptr;
    *ptr--= *ptr1;
    *ptr1++ = tmp_char;
  }
}