Fossil

/*
** If zDbName is a valid local database file, open it and return
** true.  If it is not a valid local database file, return 0.
*/
static int isValidLocalDb(const char *zDbName){
  i64 lsize;
  char *zVFileDef;

  if( file_access(zDbName, F_OK) ) return 0;
  lsize = file_size(zDbName, ExtFILE);
  if( lsize%1024!=0 || lsize<4096 ) return 0;
  db_open_or_attach(zDbName, "localdb");
  zVFileDef = db_text(0, "SELECT sql FROM localdb.sqlite_master"
                         " WHERE name=='vfile'");
  if( zVFileDef==0 ) return 0;

  /* Check to see if the checkout database has the lastest schema changes.
  ** The most recent schema change (2019-01-19) is the addition of the
  ** vmerge.mhash field.  If the schema has that one column, assume
  ** everything else is up-to-date. 
  */
  if( db_table_has_column("localdb","vmerge","mhash") ){
    return 1;   /* This is a checkout database with the latest schema */
  }

  /* If there is no vfile table, then assume we have picked up something
  ** that is not even close to being a valid checkout database */
  if( !db_table_exists("localdb","vfile") ){
    return 0;  /* Not a  DB */
  }

  /* If the "isexe" column is missing from the vfile table, then
  ** add it now.   This code added on 2010-03-06.  After all users have
  ** upgraded, this code can be safely deleted.
  */
  if( sqlite3_strglob("* isexe *", zVFileDef)!=0 ){
  if( !db_table_has_column("localdb","vfile","isexe") ){
    db_multi_exec("ALTER TABLE vfile ADD COLUMN isexe BOOLEAN DEFAULT 0");
  }

  /* If "islink"/"isLink" columns are missing from tables, then
  ** add them now.   This code added on 2011-01-17 and 2011-08-27.
  ** After all users have upgraded, this code can be safely deleted.
  */
  if( sqlite3_strglob("* islink *", zVFileDef)!=0 ){
  if( !db_table_has_column("localdb","vfile","isLink") ){
    db_multi_exec("ALTER TABLE vfile ADD COLUMN islink BOOLEAN DEFAULT 0");
    if( db_local_table_exists_but_lacks_column("stashfile", "isLink") ){
      db_multi_exec("ALTER TABLE stashfile ADD COLUMN isLink BOOL DEFAULT 0");
    }
    if( db_local_table_exists_but_lacks_column("undo", "isLink") ){
      db_multi_exec("ALTER TABLE undo ADD COLUMN isLink BOOLEAN DEFAULT 0");
    }
    if( db_local_table_exists_but_lacks_column("undo_vfile", "islink") ){
      db_multi_exec("ALTER TABLE undo_vfile ADD COLUMN islink BOOL DEFAULT 0");
    }
  }
  fossil_free(zVFileDef);

  /* The design of the vmerge table changed on 2019-01-19, adding the mhash
  ** column and changing the UNIQUE index.  However, we must ahve the
  ** repository database at hand in order to do the migration, so that
  ** step is deferred. */
  return 1;
}

/*
** Locate the root directory of the local repository tree.  The root
** directory is found by searching for a file named "_FOSSIL_" or ".fslckout"
** that contains a valid repository database.

  }

  /* Make a change to the CHECK constraint on the BLOB table for
  ** version 2.0 and later.
  */
  rebuild_schema_update_2_0();   /* Do the Fossil-2.0 schema updates */

  /* Additional checks that occur when opening the checkout database */
  if( g.localOpen ){
  /* If the checkout database was opened first, then check to make
  ** sure that the repository database that was just opened has not
  ** be replaced by a clone of the same project, with different RID
  ** values.
  */
  if( g.localOpen && !db_fingerprint_ok() ){
    /* Uncomment the following when we are ready for automatic recovery: */

    /* Ensure that the repository database that was just opened has not
    ** be replaced by a clone of the same project, with different RID
    ** values.
    */
    if( !db_fingerprint_ok() ){
      /* Uncomment the following when we are ready for automatic recovery: */
#if 0
    stash_rid_renumbering_event();
      stash_rid_renumbering_event();
#else
    fossil_print(
      "Oops. It looks like the repository database file located at\n"
      "    \"%s\"\n", zDbName
    );
    fossil_print(
      "has been swapped with a clone that may have different\n"
      "integer keys for the various artifacts. As of 2019-01-11,\n"
      "we are working on enhancing Fossil to be able to deal with\n"
      "that automatically, but we are not there yet. Sorry.\n\n"
    );
    fossil_print(
      "As an interim workaround, try:\n"
      "  %s close --force\n"
      "  %s open \"%s\" --keep\n"
      "Noting that any STASH and UNDO information "
      "WILL BE IRREVOCABLY LOST.\n\n",
      g.argv[0],
      g.argv[0], zDbName
    );
    fossil_fatal("bad fingerprint");
      fossil_print(
        "Oops. It looks like the repository database file located at\n"
        "    \"%s\"\n", zDbName
      );
      fossil_print(
        "has been swapped with a clone that may have different\n"
        "integer keys for the various artifacts. As of 2019-01-11,\n"
        "we are working on enhancing Fossil to be able to deal with\n"
        "that automatically, but we are not there yet. Sorry.\n\n"
      );
      fossil_print(
        "As an interim workaround, try:\n"
        "  %s close --force\n"
        "  %s open \"%s\" --keep\n"
        "Noting that any STASH and UNDO information "
        "WILL BE IRREVOCABLY LOST.\n\n",
        g.argv[0],
        g.argv[0], zDbName
      );
      fossil_fatal("bad fingerprint");
#endif
    }else

    /* Make sure the checkout database schema migration of 2019-01-19 
    ** (the addition of the vmerge.mhash column and making that columns
    ** part of the PRIMARY KEY) has occurred.
    */
    if( !db_table_has_column("localdb", "vmerge", "mhash") ){
      db_multi_exec("ALTER TABLE vmerge RENAME TO old_vmerge;");
      db_multi_exec(zLocalSchemaVmerge /*works-like:""*/);
      db_multi_exec(  
         "INSERT OR IGNORE INTO vmerge(id,merge,mhash)"
         "  SELECT id, merge, blob.uuid FROM old_vmerge, blob"
         "   WHERE old_vmerge.merge=blob.rid;"
         "DROP TABLE old_vmerge;"
      );
    }
  }
}

/*
** Return true if there have been any changes to the repository
** database since it was opened.
**

  }

#if defined(_WIN32) || defined(__CYGWIN__)
# define LOCALDB_NAME "./_FOSSIL_"
#else
# define LOCALDB_NAME "./.fslckout"
#endif
  db_init_database(LOCALDB_NAME, zLocalSchema,
  db_init_database(LOCALDB_NAME, zLocalSchema, zLocalSchemaVmerge,
#ifdef FOSSIL_LOCAL_WAL
                   "COMMIT; PRAGMA journal_mode=WAL; BEGIN;",
#endif
                   (char*)0);
  db_delete_on_failure(LOCALDB_NAME);
  db_open_local(0);
  if( allowSymlinks>=0 ){