advent-of-c-ode/libs/utils.c

#include "utils.h"

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

char *strreplace(char *s, const char *s1, const char *s2) {
    char *p = strstr(s, s1);
	while (p != NULL){
        size_t len1 = strlen(s1);
        size_t len2 = strlen(s2);
        if (len1 != len2){
            memmove(p + len2, p + len1, strlen(p + len1) + 1);
		}
        memcpy(p, s2, len2);
		p = strstr(s, s1);
	}
    return s;
}

char *trimwhitespace(char *str){
  char *end;

  // Trim leading space
  while(isspace((unsigned char)*str)) str++;

  if(*str == 0)  // All spaces?
    return str;

  // Trim trailing space
  end = str + strlen(str) - 1;
  while(end > str && isspace((unsigned char)*end)) end--;

  // Write new null terminator character
  end[1] = '\0';

  return str;
}