Function to trimmed string in ANSI C 11

c_string_trim.c

// COMPILE: gcc -std=c11 -Wall -Wextra c_string_trim.c -o string_trim

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

char * string_trim(char * string) {
	int s_size = strlen(string);

	int left_spaces = 0;
	for(int i=0; i<s_size; i++) {
		if(isspace(string[i])) {
			left_spaces++;
		} else {
			break;
		}
	}

	int right_spaces = 0;
	for(int i=(s_size-1); i>=0; i--) {
		if(isspace(string[i])) {
			right_spaces++;
		} else {
			break;
		}
	}

	char * new_ptr = calloc(s_size-left_spaces-right_spaces+1, sizeof(char));
	int count = 0;
	
	for(int i=left_spaces; i<(s_size-right_spaces); i++) {
		new_ptr[count++] = string[i];
	}
	new_ptr[count] = '\0';

	return new_ptr;
}

int main() {
	char string[] = "\t\t  Hello World \t\r\n";

	char * string_trimmed = string_trim(string);
	printf("'%s'\n", string_trimmed);

	free(string_trimmed);
	return 0;
}