Wildcard Matching

Implement wildcard pattern matching with support for '?' and '*'.
'?' Matches any single character.
'*' Matches any sequence of characters (including the empty sequence).
The matching should cover the entire input string (not partial).
The function prototype should be:
bool isMatch(const char *s, const char *p)
Some examples:
isMatch("aa","a") ? false
isMatch("aa","aa") ? true
isMatch("aaa","aa") ? false
isMatch("aa", "*") ? true
isMatch("aa", "a*") ? true
isMatch("ab", "?*") ? true
isMatch("aab", "c*a*b") ? false

Solution: ...

class Solution {
public:
    bool isMatch(const char *s, const char *p) {
        const char *sBackup = NULL, *pBackup = NULL;
        while (*s != '\0') {
            if (*p == '?' || *s == *p) {
                s++;
                p++;
            } else if (*p == '*') {
                while (*p == '*') p++;
                if (*p == '\0') return true;
                sBackup = s;
                pBackup = p;
            } else {
                if (!sBackup) return false;
                s = ++sBackup;
                p = pBackup;
            }
        }
        while (*p == '*') p++;
        return *s == '\0' && *p == '\0';
    }
};