Fossil

  lsize = file_size(zDbName, ExtFILE);
  if( lsize%1024!=0 || lsize<4096 ) return 0;
  db_open_or_attach(zDbName, "localdb");

  /* 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 and vfile.mhash fields.  If the schema has the vmerge.mhash
  ** 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 */

        fossil_print(
          "WARNING: The repository database has been replaced by a clone.\n"
          "Bisect history and undo have been lost.\n"
        );
      }
    }

    /* Make sure the checkout database schema migration of 2019-01-20 
    ** has occurred.
    **
    ** The 2019-01-19 migration is the addition of the vmerge.mhash and
    ** vfile.mhash columns and making the vmerge.mhash column part of the
    ** PRIMARY KEY for vmerge.
    */
    if( !db_table_has_column("localdb", "vfile", "mhash") ){
      db_multi_exec("ALTER TABLE vfile ADD COLUMN mhash;");
      db_multi_exec(
        "UPDATE vfile"
        "   SET mhash=(SELECT uuid FROM blob WHERE blob.rid=vfile.mrid)"
        " WHERE mrid!=rid;"
      );
      if( !db_table_has_column("localdb", "vmerge", "mhash") ){
        db_exec_sql("ALTER TABLE vmerge RENAME TO old_vmerge;");
        db_exec_sql(zLocalSchemaVmerge);
        db_exec_sql(  
           "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;"
        );
      }
    }

** This routine only returns true if there have been changes
** to "repository".
*/
int db_repository_has_changed(void){
  unsigned int v;
  if( !g.repositoryOpen ) return 0;
  sqlite3_file_control(g.db, "repository", SQLITE_FCNTL_DATA_VERSION, &v);
  return g.iRepoDataVers != v;               
}

/*
** Flags for the db_find_and_open_repository() function.
*/
#if INTERFACE
#define OPEN_OK_NOT_FOUND       0x001   /* Do not error out if not found */

**        (a) "fossil ui"
**        (b) "fossil server" with the --localauth option
**        (c) "fossil http" with the --localauth option
**        (d) CGI with the "localauth" setting in the cgi script.
**
** For maximum security, set "localauth" to 1.  However, because
** of the other restrictions (2) through (4), it should be safe
** to leave "localauth" set to 0 in most installations, and 
** especially on cloned repositories on workstations. Leaving
** "localauth" at 0 makes the "fossil ui" command more convenient
** to use.
*/
/*
** SETTING: lock-timeout  width=25 default=60
** This is the number of seconds that a check-in lock will be held on

/*
** SETTING: mtime-changes    boolean default=on
** Use file modification times (mtimes) to detect when
** files have been modified.  If disabled, all managed files
** are hashed to detect changes, which can be slow for large
** projects.
*/
#if FOSSIL_ENABLE_LEGACY_MV_RM
/*
** SETTING: mv-rm-files      boolean default=off
** If enabled, the "mv" and "rename" commands will also move
** the associated files within the checkout -AND- the "rm"
** and "delete" commands will also remove the associated
** files from within the checkout.
*/
#endif
/*
** SETTING: pgp-command      width=40
** Command used to clear-sign manifests at check-in.
** Default value is "gpg --clearsign -o"
*/
/*
** SETTING: forbid-delta-manifests    boolean default=off

**
** The fingerprint consists of the rcvid, a "/", and the MD5 checksum of
** the remaining fields of the RCVFROM table entry.  MD5 is used for this
** because it is 4x faster than SHA3 and 5x faster than SHA1, and there
** are no security concerns - this is just a checksum, not a security
** token.
*/
char *db_fingerprint(int rcvid, int iVersion){ 
  char *z = 0;
  Blob sql = BLOB_INITIALIZER;
  Stmt q;
  if( iVersion==0 ){
    /* The original fingerprint algorithm used "quote(mtime)".  But this
    ** could give slightly different answers depending on how the floating-
    ** point hardware is configured.  For example, it gave different

void test_fingerprint(void){
  int rcvid = 0;
  db_find_and_open_repository(OPEN_ANY_SCHEMA,0);
  if( g.argc==3 ){
    rcvid = atoi(g.argv[2]);
  }else if( g.argc!=2 ){
    fossil_fatal("wrong number of arguments");
  } 
  fossil_print("legacy:              %z\n", db_fingerprint(rcvid, 0));
  fossil_print("version-1:           %z\n", db_fingerprint(rcvid, 1));
  if( g.localOpen ){
    fossil_print("localdb:             %z\n", db_lget("fingerprint","(none)"));
    fossil_print("db_fingerprint_ok(): %d\n", db_fingerprint_ok());
  }
  fossil_print("Fossil version:      %s - %.10s %.19s\n", 
    RELEASE_VERSION, MANIFEST_DATE, MANIFEST_UUID);
}

/*
** Set the value of the "checkout" entry in the VVAR table.
**
** Also set "fingerprint" and "checkout-hash".

  fossil_free(zRepo);
  /* If the initial test fails, try again using the older fingerprint
  ** algorithm */
  if( !rc ){
    zRepo = db_fingerprint(atoi(zCkout), 0);
    rc = fossil_strcmp(zCkout,zRepo)==0;
    fossil_free(zRepo);
  }  
  fossil_free(zCkout);
  return rc;
}