Simple brute force for string matching in C

bf.c

/**
This is a simple proof of concept of a brute force algorithm for string matching with
given set of characters.
The way this works is that the algorithm counts from first to last possible combination of 
given characters. Instead of counting(incrementing) in number base 10 we use 
a new base which is derived from your set of possible characters (we count in symbols).
So if your characters list contains 27 characters the program actually counts in a 27 base
number system.

Author: Luka Vidaković
Website: http://www.lukavidakovic.com
Date: 13.9.2012.
*/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

// max length of a string and symbol set
#define MAX_LENGTH 3
// symbols/characters which will be used for generating word combinations
char symbols[] = "abcdefgh123";

char *symbolsPtr = symbols;
char **base = NULL;
int currentLength=1,i,counter;

/**
Expand base array to length+1, and set all elements to first element from possible characters
list because array[length] is overflowed so we start with 1 element bigger array from the smallest 
possible combination
*/
void expandArray(char **baseArray,char* symbols,int length) {
	baseArray = (char**) realloc(baseArray,sizeof(char*)*(length+1));
	for(i=0;i<=length;i++) {
		baseArray[i] = symbols;
	}
}

// Given the base pointer and length of string it prints the current base 
void printArray(char **baseArray,int len) {
	for(i=0;i<len;i++) {
		putchar(*baseArray[i]);
	}
	putchar('\n');
}

int main() {

	base = (char**) malloc(sizeof(char*));
	const char *symbolsEnd = symbolsPtr+strlen(symbols);

	// while length of base is smaller or equal to given string length
	while(currentLength <= MAX_LENGTH) {
		while(symbolsPtr < symbolsEnd) {
			base[currentLength-1] = symbolsPtr++;
			printArray(base,currentLength); // Combinations!
		}

		for(i=currentLength-1,counter=0;i>=0;i--) {
			if(*base[i] == *(symbolsEnd-1)) {
				counter++;
			}
			else break;
		}
		// if all positions have the highest character expand array for 1 because of the overflow 			
		if(counter == currentLength) {
			expandArray(base,symbols,currentLength);
			currentLength++;
		}
		// else "carry 1"
		else {
			base[currentLength-counter-1]++;
			for(i=currentLength-1;i>=currentLength-counter;i--) {
				base[i] = symbols;
			}
		}
		symbolsPtr = symbols;
	}
	free(base);
	return 0;
}