Split stdin lines from getline at commas

#define _POSIX_C_SOURCE 200809L
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>

/* Read stdin line by line and print each comma-separated field. */
int main(void)
{
    char *line = NULL;
    size_t capacity = 0;
    ssize_t length;
    while ((length = getline(&line, &capacity, stdin)) != -1) {
        while (length > 0 && (line[length - 1] == '\n' || line[length - 1] == '\r')) {
            line[--length] = '\0';
        }
        char *field = line;
        for (char *cursor = line;; cursor++) {
            if (*cursor != ',' && *cursor != '\0') {
                continue;
            }
            char saved = *cursor;
            *cursor = '\0';
            printf("%s\n", field);
            if (saved == '\0') break;
            field = cursor + 1;
        }
    }
    free(line);
    return 0;
}