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   1 #include <string.h>
   2 #include <stdio.h>
   3
   4 /**
   5  * tdb2 - [[WORK IN PROGRESS!]] The trivial (64bit transactional) database
   6  *
   7  * The tdb2 module provides an efficient keyword data mapping (usually
   8  * within a file).  It supports transactions, so the contents of the
   9  * database is reliable even across crashes.
  10  *
  11  * Example:
  12  *      #include <ccan/tdb2/tdb2.h>
  13  *      #include <ccan/str/str.h>
  14  *      #include <err.h>
  15  *      #include <stdio.h>
  16  *
  17  *      static void usage(void)
  18  *      {
  19  *              errx(1, "Usage: %s fetch <dbfile> <key>\n"
  20  *                   "OR %s store <dbfile> <key> <data>");
  21  *      }
  22  *
  23  *      int main(int argc, char *argv[])
  24  *      {
  25  *              struct tdb_context *tdb;
  26  *              TDB_DATA key, value;
  27  *
  28  *              if (argc < 4)
  29  *                      usage();
  30  *
  31  *              tdb = tdb_open(argv[2], 1024, TDB_DEFAULT, O_CREAT|O_RDWR,
  32  *                              0600);
  33  *              if (!tdb)
  34  *                      err(1, "Opening %s", argv[2]);
  35  *
  36  *              key.dptr = (void *)argv[3];
  37  *              key.dsize = strlen(argv[3]);
  38  *
  39  *              if (streq(argv[1], "fetch")) {
  40  *                      if (argc != 4)
  41  *                              usage();
  42  *                      value = tdb_fetch(tdb, key);
  43  *                      if (!value.dptr)
  44  *                              errx(1, "fetch %s: %s",
  45  *                                   argv[3], tdb_errorstr(tdb));
  46  *                      printf("%.*s\n", value.dsize, (char *)value.dptr);
  47  *                      free(value.dptr);
  48  *              } else if (streq(argv[1], "store")) {
  49  *                      if (argc != 5)
  50  *                              usage();
  51  *                      value.dptr = (void *)argv[4];
  52  *                      value.dsize = strlen(argv[4]);
  53  *                      if (tdb_store(tdb, key, value, 0) != 0)
  54  *                              errx(1, "store %s: %s",
  55  *                                   argv[3], tdb_errorstr(tdb));
  56  *              } else
  57  *                      usage();
  58  *
  59  *              return 0;
  60  *      }
  61  *
  62  * Maintainer: Rusty Russell <rusty@rustcorp.com.au>
  63  *
  64  * Author: Rusty Russell
  65  *
  66  * Licence: LGPLv3 (or later)
  67  */
  68 int main(int argc, char *argv[])
  69 {
  70         if (argc != 2)
  71                 return 1;
  72
  73         if (strcmp(argv[1], "depends") == 0) {
  74                 printf("ccan/hash\n");
  75                 printf("ccan/likely\n");
  76                 printf("ccan/asearch\n");
  77                 return 0;
  78         }
  79
  80         return 1;
  81 }