Product Documentation

FairCom RTG V3 Update Guide

Previous Topic

Next Topic

ctcmpcif - IFIL-based Compact Utility Included

The ctcmpcif utility has been added to the command-line utilities. This utility can be used to encrypt and decrypt c-tree data files.

Operational Model:

  • Client
  • Standalone
  • FairCom DB Standalone SQL Service

Standalone Usage

ctcmpcif <data file name> <user> <pass> <server> <-sectors> <options>

Where:

  • <-sectors> - The sector size to use. Enter a dash followed by the size of the sectors. The sector parameter is especially useful if you need to adjust a file’s PAGE_SIZE to match the FairCom Server. This option must go after <server>. The sector size is 256 is in the example below:

    ctcmpcif xx8.dat ADMIN ADMIN FAIRCOMSMS -256

<options> can be:

  • -callback - Enable notifications of compact progress.
  • -compress - Create the compacted data file with compression (defaults to zlib library if not specified in server configuration).
  • -encrypt=cipher - Create the compacted file using the specified cipher. See the encryption sections below.
    Accepted values:
    • AES: aes16, aes24, or aes32
    • Blowfish: blf8, blf9, ..., or blf56
    • DES: des8, des16, or des24
    • none
  • -flexrec - (Supported in V11.5 and later) Add Hot Alter Table support to the file.
  • -idxseg=<M>@<S> - If creating an index, use M automatic segments of size S. Size is specified in megabytes, or you can specify MB or GB as a suffix. (Example: -idxseg=10@1GB)
  • -nocompress - Create the compacted data file without compression.
  • -noflexrec - (Supported in V11.5 and later) Remove Hot Alter Table support from the file.
  • -oldsec - Use the utility's original security attribute assignment.
  • -online - (In V13 and later) Defragment the file in ctSHARED mode. Online compact is not allowed for changing encryption or compression settings.
  • -purge - Delete records that have illegal duplicate key values.
  • -redosrl - Reassign serial numbers to the records in the compacted file instead of copying the values from the original file.
  • -repairdata - Attempt repair if damaged data records are detected.
  • ‑sortmem=<N> - Set the size of sort memory to N KB in non-client builds. This option can be used to increase the rebuild speed for large files.
  • -temppath=<temporary_path> - Use the specified directory for temporary files.
  • -updifil - Update IFIL resources in the data file.
  • -x8 - Use extended create blocks read from data and index files.

Client-Side Usage

# ctcmpcif DataFileName [-purge] [-updifil] [<UserId>]
[<UserPassword> [<ServerName>]]

Where:

  • -purge - purge duplicate records.
  • -updifil - update IFIL resources in the data file.

UserID, UserPassword, and ServerName are only needed for client versions of this utility. FairCom recommends building this utility as a Single-user Standalone application.

ctcmpcif reads the IFIL structure from DataFileName and calls CompactIFileXtd() and RebuildIFileXtd() to compact and rebuild DataFileName and its associated indexes. If ctcmpcif cannot extract the IFIL from the target file, it will ask for the name of another copy of the file from which to extract the IFIL information.

Prior to FairCom DB V9.3, several option values were defined such as updateIFIL, purgeIFIL, and badpartIFIL, that can be specified. These values are specified by adding them together. For example: myifil.tfilno = updateIFIL + purgeIFIL. A new approach simplifies checking of these options. The following option values are now specified in ctport.h:

#define updateIFILoption 0x0002

#define purgeIFILoption 0x0004

#define badpartIFILoption 0x0008

#define redosrlIFILoption 0x0010

These values can now be OR-ed together and the negative of the result stored in the tfilno field of the IFIL structure passed to the compact or rebuild function. For example, to indicate that you want to assign new serial numbers, do the following:

myifil.tfilno = -redosrlIFILoption;

CMPIFIL(&myifil);

If you want to also use more than one option when compacting or rebuilding a file, OR them in to the value and negate the result. For example,

/* assign new serial numbers and update IFIL resource. */

myifil.tfilno = -(redosrlIFILoption | updateIFILoption);

CMPIFIL(&myifil);

ctcmpcif will attempt to open files of any page size definition. In addition, in standalone mode, it will create the new file based on the provided page size.

Note: This tool does not compact partitioned files. If you attempt to compact a partitioned file, the tool will return PCMP_ERR (954, compacting partitioned file not supported).

Changing Encryption Attributes

In V11 and later, the compact utility can optionally change the encryption attributes. To use this option, OR in the setencryptIFILoption bit into the tfilno field of the IFIL structure whose address you pass to the compact API function. When using this and other options, remember to negate the tfilno value after you OR in the options. For example:

myifil.tfilno = -(redosrlIFILoption | setencryptIFILoption);

CMPIFIL(&myifil);

Specifying the Encryption Cipher

In V11 and later, the ctcmpcif utility supports an option to specify the encryption cipher for the data and index files created by the compact operation. Usage:

-encrypt=cipher - Create the compacted file using the specified cipher:

  • for AES, use aes16, aes24, or aes32
  • for Blowfish, use blf8, blf9, ..., or blf56
  • for DES, use des8, des16, or des24
  • for Twofish, use twf16, twf24, or twf32
  • for no encryption, use none

Note: If an index file does not exist, the original data file's encryption attributes are used when creating that index file.

To change the encryption attributes of a file using this ctcmpcif compact utility or the compact API function from a client, you must add the option CHANGE_ENCRYPTION_ON_COMPACT YES to ctsrvr.cfg. Otherwise, the operation fails with error NSUP_ERR (454, not supported).

Environment Variable to Enable Advanced Encryption

In V11.5 and later, c-tree supports enabling advanced encryption at run time using an environment variable. Set the environment variable CTREE_ADVANCED_ENCRYPTION to YES to enable advanced encryption if it is supported. This environment variable can be used to allow c-tree utilities to enable advanced encryption even if they haven't been updated yet to automatically enable advanced encryption when needed. Examples include the rebuild and compact utilities, ctrbldif and ctcmpcif.

Note: If c-tree does not support advanced encryption and this environment variable is set, the c-tree initialization will fail.

Considerations

  • Even without the -x8 option, some extended create block settings such as the huge file, extended header, and 6-byte transaction number options, are always applied to new files.
  • The -x8 option requires all associated index files that are referenced in the data file's IFIL structure to exist, as the utilities use OpenIFile() to open the data file and all associated index files to read the extended create block values.

When an application calls the standalone version of the Xtd8 file compact or rebuild functions (for example, CMPIFILX8() or RBLIFILX8()), index files created by the compact or rebuild no longer have the 6-byte transaction number attribute enabled if the specified extended create block's x8mode field has the ctNO6BTRAN bit set.

  • A rebuild or compact will fail with the new error code TFLN_ERR (943) when a client library that supports the new rebuild or compact option format attempts to use this feature with a FairCom Server that does not support this new format.
  • In V11 and later, the compact and rebuild API functions preserve the original files' encryption attributes by default. If the index files don't exist when compact/rebuild are called, they will be created with the data file's encryption attributes.
  • In V11 and later, the compact utility always deletes and recreates the index files after saving the resources from the original index file. This provides the expected behavior of (possibly) reducing the size of the index file.

See also

  • File Recovery in the FairCom DB Developer's Guide
  • Updates in handling of security attributes
  • Preventing Possible Data Loss with Compact & Rebuild Operations

TOCIndex