hm.c

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

static int hash(char *key, int capacity) {
    int h = 0;
    for (size_t i = 0; i < strlen(key); ++i) {
        h = (h + key[i] * 43) % capacity;
    }
    return h;
}

static int rehash(char *key) {
    return 1;
}

static int find_index(hm h, char *key) {
    int i    = hash(key, h.capacity);
    int init = i;
    while (h.table[i].state != empty &&
           strncmp(h.table[i].key, key, MAX_LEN) != 0) {
        i = (i + rehash(key)) % h.capacity;
        if (i == init) {
            return -1;
        }
    }
    return i;
}

void hm_init(hm *h, int capacity) {
    h->table    = malloc(capacity * sizeof(cell_t));
    h->capacity = capacity;
    for (int i = 0; i < h->capacity; ++i) {
        h->table[i].state = empty;
    }
}

void hm_destroy(hm *h) {
    free(h->table);
    h->table    = NULL;
    h->capacity = -1;
}

bool hm_set(hm *h, char *key, char *value) {
    int i    = hash(key, h->capacity);
    int init = i;
    while (h->table[i].state == occupied &&
           strncmp(h->table[i].key, key, MAX_LEN) != 0) {
        i = (i + rehash(key)) % h->capacity;
        if (i == init) {
            return false;
        }
    }
    if (strncpy(h->table[i].key, key, MAX_LEN) == NULL) {
        return false;
    };
    if (strncpy(h->table[i].value, value, MAX_LEN) == NULL) {
        return false;
    };
    h->table[i].state = occupied;
    return true;
}

char *hm_get(hm h, char *key) {
    int i = find_index(h, key);
    return (i >= 0 && h.table[i].state == occupied) ? h.table[i].value : NULL;
}

char *hm_remove(hm *h, char *key) {
    int i = find_index(*h, key);
    if (i >= 0 && h->table[i].state == occupied) {
        h->table[i].state = deleted;
        return h->table[i].value;
    } else {
        return NULL;
    }
}

void hm_print(hm h) {
    for (int i = 0; i < h.capacity; ++i) {
        if (h.table[i].state == occupied) {
            printf("[%d], key: %s, value: %s\n", i, h.table[i].key,
                h.table[i].value);

        } else {
            printf("[%d], key: none, value: none\n", i);
        }
    }
}