019
20.10.2003, 12:19 Uhr
virtual
Sexiest Bit alive
(Operator)
|
Da haste aber glück: ich habe grade sowas zufälligerweise grade fertig geschrieben (Igitt, muß grade C machen!) - Vorgefertigt gibt es da aber nichts:
Bisher nicht in die Tiefe getestet:
| C++: |
/** like_compare
* This compares the a key and a string, whereas the key may contain wildcards:
* '?' - Means one arb. character
* '*' - Means 0-N arb. characters
* @param <code>key</code> Key to compare
* @param <code>str</code> String to compare
* @return -1, if mismatch, 0 if exact match. If the value is positive, the
* match is as better as smaller the result is.
*/
int
like_compare(
const char* key,
const char* str)
{
int match = 0;
size_t len = 0;
/*
* Assert parameters
*/
if (NULL==key || NULL==str)
{
return -1;
}
/*
* Loop to consume the entire key
*/
len = strlen(str);
while (*key)
{
size_t var_min = 0;
int var_max = 0;
size_t fix_len = 0;
size_t i=0;
/*
* analye next portion of key.
*
*/
while ('?'==*key || '*'==*key)
{
if ('?'==*key++)
++var_min;
else
var_max = 1;
}
while (key[fix_len] && '?'!=key[fix_len] && '*'!=key[fix_len])
{
++fix_len;
}
/*
* Check minimum count of unspecified characters (number of '?')
*/
if (len<var_min)
{
/* str too short */
return -1;
}
str += var_min;
len -= var_min;
match += var_min;
/*
* Check next fixed part and variable count of unspecified characters
*/
if (var_max)
{
int found = 0;
/*
* there is at least one '*' now in key. if no further fixed
* text follows, we are ready so far, because this must be the
* end of the key
*/
if (0==fix_len)
{
match += 2*len;
return match;
}
/*
* Now we have to find the fixed text somewhere in str
*/
for (i=0; i<len-fix_len && !found; ++i, --len, ++str, match += 2)
{
found = 0==strncmp(key, str, fix_len);
;
}
if (!found)
{
/* mismatch */
return -1;
}
key += fix_len;
str += fix_len-1;
}else
{
/*
* There is no '*', so the fixed part must match!
*/
if (len<fix_len)
{
/* str too short */
return -1;
}
for(i=0; i<fix_len; ++i, ++key, ++str, --len)
{
if (*str != *key)
{
/* mismatch */
return -1;
}
}
}
}
/*
* Final check
*/
if (*str)
{
/* Mismatch (key too short) */
return -1;
}
return match;
}
|
--
Gruß, virtual
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Ich eß' nur was ein Gesicht hat (Creme 21) |
