Foro de elhacker.net

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
char *fn_strtok(char *str, char const *set);
 
int main(void)
{
   char str[] = "?a???b,,,#c";
 
   printf("\"%s\"\n", strtok(str, "?"));
   printf("\"%s\"\n", strtok(NULL, ","));
   printf("\"%s\"\n", strtok(NULL, "#,"));
   printf("%p\n", (void *) strtok(NULL, "?"));
 
   strcpy(str, "?a???b,,,#c");
 
   printf("\"%s\"\n", fn_strtok(str, "?"));
   printf("\"%s\"\n", fn_strtok(NULL, ","));
   printf("\"%s\"\n", fn_strtok(NULL, "#,"));
   printf("%p\n", (void *) fn_strtok(NULL, "?"));
 
   return EXIT_SUCCESS;
}
 
char *fn_strtok(char *str, char const *set)
{
   static char *p;
 
   if (str == NULL)
      str = p;
 
   p = str += strspn(str, set);
   if (*str == '\0')
      str = NULL;
   else {
      p += strcspn(p, set);
 
      if (*p != '\0')
         *p++ = '\0';
   }
 
   return str;
}

"a"
"??b"
"c"
(null)
"a"
"??b"
"c"
(null)

/***
*wcscat.c - contains wcscat() and wcscpy()
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       wcscat() appends one wchar_t string onto another.
*       wcscpy() copies one wchar_t string into another.
*
*       wcscat() concatenates (appends) a copy of the source string to the
*       end of the destination string, returning the destination string.
*       Strings are wide-character strings.
*
*       wcscpy() copies the source string to the spot pointed to be
*       the destination string, returning the destination string.
*       Strings are wide-character strings.
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wchar_t *wcscat(dst, src) - concatenate (append) one wchar_t string to another
*
*Purpose:
*       Concatenates src onto the end of dest.  Assumes enough
*       space in dest.
*
*Entry:
*       wchar_t *dst - wchar_t string to which "src" is to be appended
*       const wchar_t *src - wchar_t string to be appended to the end of "dst"
*
*Exit:
*       The address of "dst"
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl wcscat (
        wchar_t * dst,
        const wchar_t * src
        )
{
        wchar_t * cp = dst;
 
        while( *cp )
                cp++;                   /* find end of dst */
 
        while( *cp++ = *src++ ) ;       /* Copy src to end of dst */
 
        return( dst );                  /* return dst */
 
}
 
 
/***
*wchar_t *wcscpy(dst, src) - copy one wchar_t string over another
*
*Purpose:
*       Copies the wchar_t string src into the spot specified by
*       dest; assumes enough room.
*
*Entry:
*       wchar_t * dst - wchar_t string over which "src" is to be copied
*       const wchar_t * src - wchar_t string to be copied over "dst"
*
*Exit:
*       The address of "dst"
*
*Exceptions:
*******************************************************************************/
 
wchar_t * __cdecl wcscpy(wchar_t * dst, const wchar_t * src)
{
        wchar_t * cp = dst;
 
        while( *cp++ = *src++ )
                ;               /* Copy src over dst */
 
        return( dst );
}
 
 

/***
*wcschr.c - search a wchar_t string for a given wchar_t character
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines wcschr() - search a wchar_t string for a wchar_t character
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wchar_t *wcschr(string, c) - search a string for a wchar_t character
*
*Purpose:
*       Searches a wchar_t string for a given wchar_t character,
*       which may be the null character L'\0'.
*
*Entry:
*       wchar_t *string - wchar_t string to search in
*       wchar_t c - wchar_t character to search for
*
*Exit:
*       returns pointer to the first occurence of c in string
*       returns NULL if c does not occur in string
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl wcschr (
        const wchar_t * string,
        wchar_t ch
        )
{
        while (*string && *string != (wchar_t)ch)
                string++;
 
        if (*string == (wchar_t)ch)
                return((wchar_t *)string);
        return(NULL);
}
 
 

/***
*wcscmp.c - routine to compare two wchar_t strings (for equal, less, or greater)
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       Compares two wide-character strings, determining their lexical order.
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wcscmp - compare two wchar_t strings,
*        returning less than, equal to, or greater than
*
*Purpose:
*       wcscmp compares two wide-character strings and returns an integer
*       to indicate whether the first is less than the second, the two are
*       equal, or whether the first is greater than the second.
*
*       Comparison is done wchar_t by wchar_t on an UNSIGNED basis, which is to
*       say that Null wchar_t(0) is less than any other character.
*
*Entry:
*       const wchar_t * src - string for left-hand side of comparison
*       const wchar_t * dst - string for right-hand side of comparison
*
*Exit:
*       returns -1 if src <  dst
*       returns  0 if src == dst
*       returns +1 if src >  dst
*
*Exceptions:
*
*******************************************************************************/
 
int __cdecl wcscmp (
        const wchar_t * src,
        const wchar_t * dst
        )
{
        int ret = 0 ;
 
        while( ! (ret = (int)(*src - *dst)) && *dst)
                ++src, ++dst;
 
        if ( ret < 0 )
                ret = -1 ;
        else if ( ret > 0 )
                ret = 1 ;
 
        return( ret );
}
 
 

/***
*wcslen.c - contains wcslen() routine
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       wcslen returns the length of a null-terminated wide-character string,
*       not including the null wchar_t itself.
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wcslen - return the length of a null-terminated wide-character string
*
*Purpose:
*       Finds the length in wchar_t's of the given string, not including
*       the final null wchar_t (wide-characters).
*
*Entry:
*       const wchar_t * wcs - string whose length is to be computed
*
*Exit:
*       length of the string "wcs", exclusive of the final null wchar_t
*
*Exceptions:
*
*******************************************************************************/
 
size_t __cdecl wcslen (
        const wchar_t * wcs
        )
{
        const wchar_t *eos = wcs;
 
        while( *eos++ ) ;
 
        return( (size_t)(eos - wcs - 1) );
}
 
 

/***
*wcsncpy.c - copy at most n characters of wide-character string
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines wcsncpy() - copy at most n characters of wchar_t string
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wchar_t *wcsncpy(dest, source, count) - copy at most n wide characters
*
*Purpose:
*       Copies count characters from the source string to the
*       destination.  If count is less than the length of source,
*       NO NULL CHARACTER is put onto the end of the copied string.
*       If count is greater than the length of sources, dest is padded
*       with null characters to length count (wide-characters).
*
*
*Entry:
*       wchar_t *dest - pointer to destination
*       wchar_t *source - source string for copy
*       size_t count - max number of characters to copy
*
*Exit:
*       returns dest
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl wcsncpy (
        wchar_t * dest,
        const wchar_t * source,
        size_t count
        )
{
        wchar_t *start = dest;
 
        while (count && (*dest++ = *source++))    /* copy string */
                count--;
 
        if (count)                              /* pad out with zeroes */
                while (--count)
                        *dest++ = L'\0';
 
        return(start);
}
 
 

/***
*wcspbrk.c - scans wide character string for a character from control string
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines wcspbrk()- returns pointer to the first wide-character in
*       a wide-character string in the control string.
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wchar_t *wcspbrk(string, control) - scans string for a character from control
*
*Purpose:
*       Returns pointer to the first wide-character in
*       a wide-character string in the control string.
*
*Entry:
*       wchar_t *string - string to search in
*       wchar_t *control - string containing characters to search for
*
*Exit:
*       returns a pointer to the first character from control found
*       in string.
*       returns NULL if string and control have no characters in common.
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl wcspbrk (
        const wchar_t * string,
        const wchar_t * control
        )
{
        wchar_t *wcset;
 
        /* 1st char in control string stops search */
        while (*string) {
            for (wcset = (wchar_t *) control; *wcset; wcset++) {
                if (*wcset == *string) {
                    return (wchar_t *) string;
                }
            }
            string++;
        }
        return NULL;
}
 
 

/***
*wcsrchr.c - find last occurrence of wchar_t character in wide string
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines wcsrchr() - find the last occurrence of a given character
*       in a string (wide-characters).
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wchar_t *wcsrchr(string, ch) - find last occurrence of ch in wide string
*
*Purpose:
*       Finds the last occurrence of ch in string.  The terminating
*       null character is used as part of the search (wide-characters).
*
*Entry:
*       wchar_t *string - string to search in
*       wchar_t ch - character to search for
*
*Exit:
*       returns a pointer to the last occurrence of ch in the given
*       string
*       returns NULL if ch does not occurr in the string
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl wcsrchr (
        const wchar_t * string,
        wchar_t ch
        )
{
        wchar_t *start = (wchar_t *)string;
 
        while (*string++)                       /* find end of string */
                ;
                                                /* search towards front */
        while (--string != start && *string != (wchar_t)ch)
                ;
 
        if (*string == (wchar_t)ch)             /* wchar_t found ? */
                return( (wchar_t *)string );
 
        return(NULL);
}
 
 

/***
*wcsrev.c - reverse a wide-character string in place
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines _wcsrev() - reverse a wchar_t string in place (not including
*       L'\0' character)
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wchar_t *_wcsrev(string) - reverse a wide-character string in place
*
*Purpose:
*       Reverses the order of characters in the string.  The terminating
*       null character remains in place (wide-characters).
*
*Entry:
*       wchar_t *string - string to reverse
*
*Exit:
*       returns string - now with reversed characters
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl _wcsrev (
        wchar_t * string
        )
{
        wchar_t *start = string;
        wchar_t *left = string;
        wchar_t ch;
 
        while (*string++)                 /* find end of string */
                ;
        string -= 2;
 
        while (left < string)
        {
                ch = *left;
                *left++ = *string;
                *string-- = ch;
        }
 
        return(start);
}
 
 

/***
*wcsspn.c - find length of initial substring of chars from a control string
*       (wide-character strings)
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines wcsspn() - finds the length of the initial substring of
*       a string consisting entirely of characters from a control string
*       (wide-character strings).
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*int wcsspn(string, control) - find init substring of control chars
*
*Purpose:
*       Finds the index of the first character in string that does belong
*       to the set of characters specified by control.  This is
*       equivalent to the length of the initial substring of string that
*       consists entirely of characters from control.  The L'\0' character
*       that terminates control is not considered in the matching process
*       (wide-character strings).
*
*Entry:
*       wchar_t *string - string to search
*       wchar_t *control - string containing characters not to search for
*
*Exit:
*       returns index of first wchar_t in string not in control
*
*Exceptions:
*
*******************************************************************************/
 
size_t __cdecl wcsspn (
        const wchar_t * string,
        const wchar_t * control
        )
{
        wchar_t *str = (wchar_t *) string;
        wchar_t *ctl;
 
        /* 1st char not in control string stops search */
        while (*str) {
            for (ctl = (wchar_t *)control; *ctl != *str; ctl++) {
                if (*ctl == (wchar_t)0) {
                    /*
                     * reached end of control string without finding a match
                     */
                    return str - string;
                }
            }
            str++;
        }
        /*
         * The whole string consisted of characters from control
         */
        return str - string;
}
 
 

/***
*wcsstr.c - search for one wide-character string inside another
*
*       Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines wcsstr() - search for one wchar_t string inside another
*
*******************************************************************************/
 
 
#include <string.h>
 
/***
*wchar_t *wcsstr(string1, string2) - search for string2 in string1
*       (wide strings)
*
*Purpose:
*       finds the first occurrence of string2 in string1 (wide strings)
*
*Entry:
*       wchar_t *string1 - string to search in
*       wchar_t *string2 - string to search for
*
*Exit:
*       returns a pointer to the first occurrence of string2 in
*       string1, or NULL if string2 does not occur in string1
*
*Uses:
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl wcsstr (
        const wchar_t * wcs1,
        const wchar_t * wcs2
        )
{
        wchar_t *cp = (wchar_t *) wcs1;
        wchar_t *s1, *s2;
 
        while (*cp)
        {
                s1 = cp;
                s2 = (wchar_t *) wcs2;
 
                while ( *s1 && *s2 && !(*s1-*s2) )
                        s1++, s2++;
 
                if (!*s2)
                        return(cp);
 
                cp++;
        }
 
        return(NULL);
}
 
 

/***
*wcstok.c - tokenize a wide-character string with given delimiters
*
*       Copyright (c) 1989-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       defines wcstok() - breaks wide-character string into series of token
*       via repeated calls.
*
*******************************************************************************/
 
 
#include "headers.hxx"
 
#ifndef X_STRING_H_
#define X_STRING_H_
#include <string.h>
#endif
 
/***
*wchar_t *wcstok(string, control) - tokenize string with delimiter in control
*       (wide-characters)
*
*Purpose:
*       wcstok considers the string to consist of a sequence of zero or more
*       text tokens separated by spans of one or more control chars. the first
*       call, with string specified, returns a pointer to the first wchar_t of
*       the first token, and will write a null wchar_t into string immediately
*       following the returned token. subsequent calls with zero for the first
*       argument (string) will work thru the string until no tokens remain. the
*       control string may be different from call to call. when no tokens remain
*       in string a NULL pointer is returned. remember the control chars with a
*       bit map, one bit per wchar_t. the null wchar_t is always a control char
*       (wide-characters).
*
*Entry:
*       wchar_t *string - wchar_t string to tokenize, or NULL to get next token
*       wchar_t *control - wchar_t string of characters to use as delimiters
*
*Exit:
*       returns pointer to first token in string, or if string
*       was NULL, to next token
*       returns NULL when no more tokens remain.
*
*Uses:
*
*Exceptions:
*
*******************************************************************************/
 
wchar_t * __cdecl wcstok (
        wchar_t * string,
        const wchar_t * control
        )
{
    wchar_t *token;
    const wchar_t *ctl;
 
    THREADSTATE *pts = GetThreadState();
 
    /* If string==NULL, continue with previous string */
    if (!string)
        string = pts->wtoken;
 
    /* Find beginning of token (skip over leading delimiters). Note that
     * there is no token iff this loop sets string to point to the terminal
     * null (*string == '\0') */
 
    while (*string) {
            for (ctl=control; *ctl && *ctl != *string; ctl++)
                    ;
            if (!*ctl) break;
            string++;
    }
 
    token = string;
 
    /* Find the end of the token. If it is not the end of the string,
     * put a null there. */
    for ( ; *string ; string++ ) {
            for (ctl=control; *ctl && *ctl != *string; ctl++)
                    ;
            if (*ctl) {
                    *string++ = '\0';
                    break;
            }
    }
 
    /* Update nextoken (or the corresponding field in the per-thread data
     * structure */
    pts->wtoken = string;
 
    /* Determine if a token has been found. */
    if ( token == string )
            return NULL;
    else
            return token;
}
 
 

/***
*wcstol.c - Contains C runtimes wcstol and wcstoul
*
*       Copyright (c) 1989-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
*       wcstol - convert wchar_t string to long signed integer
*       wcstoul - convert wchar_t string to long unsigned integer
*
*******************************************************************************/
 
#include "headers.hxx"
 
#ifndef X_STDLIB_H_
#define X_STDLIB_H_
#include <stdlib.h>
#endif
 
#ifndef X_LIMITS_H_
#define X_LIMITS_H_
#include <limits.h>
#endif
 
#ifndef X_CTYPE_H_
#define X_CTYPE_H_
#include <ctype.h>
#endif
 
/***
*wcstol, wcstoul(nptr,endptr,ibase) - Convert ascii string to long un/signed
*       int.
*
*Purpose:
*       Convert an ascii string to a long 32-bit value.  The base
*       used for the caculations is supplied by the caller.  The base
*       must be in the range 0, 2-36.  If a base of 0 is supplied, the
*       ascii string must be examined to determine the base of the
*       number:
*               (a) First char = '0', second char = 'x' or 'X',
*                   use base 16.
*               (b) First char = '0', use base 8
*               (c) First char in range '1' - '9', use base 10.
*
*       If the 'endptr' value is non-NULL, then wcstol/wcstoul places
*       a pointer to the terminating character in this value.
*       See ANSI standard for details
*
*Entry:
*       nptr == NEAR/FAR pointer to the start of string.
*       endptr == NEAR/FAR pointer to the end of the string.
*       ibase == integer base to use for the calculations.
*
*       string format: [whitespace] [sign] [0] [x] [digits/letters]
*
*Exit:
*       Good return:
*               result
*
*       Overflow return:
*               wcstol -- LONG_MAX or LONG_MIN
*               wcstoul -- ULONG_MAX
*               wcstol/wcstoul -- errno == ERANGE
*
*       No digits or bad base return:
*               0
*               endptr = nptr*
*
*Exceptions:
*       None.
*******************************************************************************/
 
/* flag values */
#define FL_UNSIGNED   1       /* wcstoul called */
#define FL_NEG        2       /* negative sign found */
#define FL_OVERFLOW   4       /* overflow occured */
#define FL_READDIGIT  8       /* we've read at least one correct digit */
 
#pragma warning (disable: 4305)
#pragma warning (disable: 4306)
 
static unsigned long __cdecl wcstoxl (
        const wchar_t *nptr,
        wchar_t **endptr,
        int ibase,
        int flags
        )
{
        const wchar_t *p;
        wchar_t c;
        unsigned long number;
        unsigned digval;
        unsigned long maxval;
 
        p = nptr;                       /* p is our scanning pointer */
        number = 0;                     /* start with zero */
 
        c = *p++;                       /* read char */
        while (_istspace(c))
                c = *p++;               /* skip whitespace */
 
        if (c == '-') {
                flags |= FL_NEG;        /* remember minus sign */
                c = *p++;
        }
        else if (c == '+')
                c = *p++;               /* skip sign */
 
        if (ibase < 0 || ibase == 1 || ibase > 36) {
                /* bad base! */
                if (endptr)
                        /* store beginning of string in endptr */
                        *endptr = (wchar_t *)nptr;
                return 0L;              /* return 0 */
        }
        else if (ibase == 0) {
                /* determine base free-lance, based on first two chars of
                   string */
                if (c != L'0')
                        ibase = 10;
                else if (*p == L'x' || *p == L'X')
                        ibase = 16;
                else
                        ibase = 8;
        }
 
        if (ibase == 16) {
                /* we might have 0x in front of number; remove if there */
                if (c == L'0' && (*p == L'x' || *p == L'X')) {
                        ++p;
                        c = *p++;       /* advance past prefix */
                }
        }
 
        /* if our number exceeds this, we will overflow on multiply */
        maxval = ULONG_MAX / ibase;
 
 
        for (;;) {      /* exit in middle of loop */
                /* convert c to value */
                if (_istdigit(c))
                        digval = c - L'0';
                else if (_istalpha(c))
                        digval = (TCHAR)CharUpper((LPTSTR)c) - L'A' + 10;
                else
                        break;
                if (digval >= (unsigned)ibase)
                        break;          /* exit loop if bad digit found */
 
                /* record the fact we have read one digit */
                flags |= FL_READDIGIT;
 
                /* we now need to compute number = number * base + digval,
                   but we need to know if overflow occured.  This requires
                   a tricky pre-check. */
 
                if (number < maxval || (number == maxval &&
                (unsigned long)digval <= ULONG_MAX % ibase)) {
                        /* we won't overflow, go ahead and multiply */
                        number = number * ibase + digval;
                }
                else {
                        /* we would have overflowed -- set the overflow flag */
                        flags |= FL_OVERFLOW;
                }
 
                c = *p++;               /* read next digit */
        }
 
        --p;                            /* point to place that stopped scan */
 
        if (!(flags & FL_READDIGIT)) {
                /* no number there; return 0 and point to beginning of
                   string */
                if (endptr)
                        /* store beginning of string in endptr later on */
                        p = nptr;
                number = 0L;            /* return 0 */
        }
        else if ( (flags & FL_OVERFLOW) ||
                  ( !(flags & FL_UNSIGNED) &&
                    ( ( (flags & FL_NEG) && (number > -LONG_MIN) ) ||
                      ( !(flags & FL_NEG) && (number > LONG_MAX) ) ) ) )
        {
                /* overflow or signed overflow occurred */
                //errno = ERANGE;
                if ( flags & FL_UNSIGNED )
                        number = ULONG_MAX;
                else if ( flags & FL_NEG )
                        number = (unsigned long)(-LONG_MIN);
                else
                        number = LONG_MAX;
        }
 
        if (endptr != NULL)
                /* store pointer to char that stopped the scan */
                *endptr = (wchar_t *)p;
 
        if (flags & FL_NEG)
                /* negate result if there was a neg sign */
                number = (unsigned long)(-(long)number);
 
        return number;                  /* done. */
}
 
#pragma warning (default: 4305)
#pragma warning (default: 4306)
 
long __cdecl wcstol (
        const wchar_t *nptr,
        wchar_t **endptr,
        int ibase
        )
{
        return (long) wcstoxl(nptr, endptr, ibase, 0);
}
 
unsigned long __cdecl wcstoul (
        const wchar_t *nptr,
        wchar_t **endptr,
        int ibase
        )
{
        return wcstoxl(nptr, endptr, ibase, FL_UNSIGNED);
}