tchdbex.c

Tokyo Cabinet的Tokyo Cabinet 是一个DBM的实现。这里的数据库由一系列key-value对的记录构成。key和value都可以是任意长度的字节序列,既可以是二进制也可以是字符

#include <tcutil.h>
#include <tchdb.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdint.h>

int main(int argc, char **argv){
  TCHDB *hdb;
  int ecode;
  char *key, *value;

  /* create the object */
  hdb = tchdbnew();

  /* open the database */
  if(!tchdbopen(hdb, "casket.tch", HDBOWRITER | HDBOCREAT)){
    ecode = tchdbecode(hdb);
    fprintf(stderr, "open error: %s\n", tchdberrmsg(ecode));
  }

  /* store records */
  if(!tchdbput2(hdb, "foo", "hop") ||
     !tchdbput2(hdb, "bar", "step") ||
     !tchdbput2(hdb, "baz", "jump")){
    ecode = tchdbecode(hdb);
    fprintf(stderr, "put error: %s\n", tchdberrmsg(ecode));
  }

  /* retrieve records */
  value = tchdbget2(hdb, "foo");
  if(value){
    printf("%s\n", value);
    free(value);
  } else {
    ecode = tchdbecode(hdb);
    fprintf(stderr, "get error: %s\n", tchdberrmsg(ecode));
  }

  /* traverse records */
  tchdbiterinit(hdb);
  while((key = tchdbiternext2(hdb)) != NULL){
    value = tchdbget2(hdb, key);
    if(value){
      printf("%s:%s\n", key, value);
      free(value);
    }
    free(key);
  }

  /* close the database */
  if(!tchdbclose(hdb)){
    ecode = tchdbecode(hdb);
    fprintf(stderr, "close error: %s\n", tchdberrmsg(ecode));
  }

  /* delete the object */
  tchdbdel(hdb);

  return 0;
}