lander/lsm/src/store/lsm_store.c

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

#include "lsm.h"
#include "lsm/store.h"
#include "lsm/trie.h"
#include "lsm/store_internal.h"

lsm_error lsm_store_init(lsm_store **ptr) {
  lsm_store *store = calloc(1, sizeof(lsm_store));

  if (store == NULL) {
    return lsm_error_failed_alloc;
  }

  lsm_error res = lsm_trie_init(&store->trie);

  if (res != lsm_error_ok) {
    free(store);

    return res;
  }

  *ptr = store;

  return lsm_error_ok;
}

lsm_error lsm_store_open(lsm_store **ptr, char *db_path, char *data_path) {
  lsm_store *store;
  LSM_RES(lsm_store_init(&store));

  // TODO implement all of reading the db file

  store->db_path = db_path;
  store->data_path = data_path;

  *ptr = store;

  return lsm_error_ok;
}

lsm_error lsm_store_search(lsm_entry **out, lsm_store *store, lsm_str *key) {
  return lsm_trie_search((void **)out, store->trie, key);
}

lsm_error lsm_store_insert(lsm_entry **out, lsm_store *store, lsm_str *key) {
  lsm_entry *entry;

  LSM_RES(lsm_entry_init(&entry));
  LSM_RES(lsm_trie_insert(store->trie, key, entry));

  entry->key = key;
  *out = entry;

  return lsm_error_ok;
}

lsm_error lsm_store_data_append(lsm_store *store, lsm_entry *entry, lsm_str *data) {
  uint64_t new_len = entry->data.len + lsm_str_len(data);

  // Data is in memory and still fits -> keep it in memory
  if ((new_len <= LSM_STORE_DISK_THRESHOLD) && (!entry->data.on_disk)) {
    char *buf = realloc(entry->data.value.ptr, new_len * sizeof(char));

    if (buf == NULL) {
      return lsm_error_failed_alloc;
    }

    memcpy(&buf[entry->data.len], lsm_str_ptr(data), lsm_str_len(data));
    entry->data.value.ptr = buf;
    entry->data.len = new_len;
  }
  // Data will end up on disk
  else {
    // Data is not yet on disk, so we create the file
    if (!entry->data.on_disk) {

    }
  }
}