Domain Creators

There are two keys to a domain creator; one has destroy rights, the other does not. Let DC represent a domain creator key of either type. A domain creator has a key called its "brander".

DC(DOMAINCREATOR__CREATE{=12};SB==>c;D)

Attempts to create a domain. SB must be an official space bank; if not, c will be 1. The domain will be constructed of three nodes obtained from the space bank SB; if three nodes cannot be obtained, c will be 2 and SB will be unchanged. If successful, D will be the only domain key to a new domain. D has destroy rights. The domain's brand will be the brander of this DC. This call is prompt if SB is. C1 through C13 and C16 through C47 will be DK(0).

While only you hold D after this call, consider (iden), (id-ex) and (idth) about how others might acquire D if access to DC is not suitably restricted.

{obsolete}DC(DOMAINCREATOR__CREATE_DOMAIN{=0};,SB==>c;D)
Same as the above, except the unusual position of the SB key.

DC(DOMAINCREATOR__DESTROY_DOMAIN{=1};D,SB==>c;)
Attempts to destroy domain D. D must be a domain key to a domain whose brand is the brander of this DC. If SB is not an official space bank c will be 1. If the attempt to destroy any of the three nodes of the domain fails {e.g., because SB is not the same space bank that was used to create the domain}, c will be 2. If D is not a domain with the right brand, c will be 3. Otherwise, the operation is successful, c is 0, and all keys to D become DK(0). This call is prompt if SB is. {The databyte of D is ignored.}

DC(DOMAINCREATOR__DESTROY_ME{=8},(4,n);RE,SB,,EX)
Destroys the domain designated by resume key EX {the caller} and returns to resume key RE. Useful for a domain that wants to commit suicide and notify someone else when it has. If EX is not a resume key to a domain whose brand is the brander of this DC, return code 3 is returned to EX. If SB is not an official space bank, return code 1 is returned to EX. If the attempt to destroy any of the three nodes of the domain fails, return code 2 is returned to EX. Otherwise, return code n is returned to RE. If the string for n has fewer than 4 bytes it is padded with zeros. Similar to "DESTROY_DOMAIN" above.

{obsolete}DC(DOMAINCREATOR__DESTROY_CALLER{=X'40000000'}+n;RE,SB,,EX ) where 0 <= n < 2**30
Similar to the above, but the return code n is restricted.

DC(DOMAINCREATOR__IDENTIFY_ENTRY{=2};E==>c;D)
If E is a start key and the brand of the domain designated by E is the brander of this DC then this operation returns the databyte {(crent)} of E in c and a domain key to E's domain in D; otherwise it returns -1 in c. The databyte of D will be zero. This call is prompt.

DC(DOMAINCREATOR__IDENTIFY_EXIT{=3};E==>c;D)
Similar to "identify entry". E must be a return or fault key. See (p3,res-ex) about why restart keys are excluded.

{obsolete}DC(DOMAINCREATOR__DESTROY{=4};,SB==>c;)
Attempts to destroy DC. If DC does not have destroy rights, c will be kt+2. If SB is not an official prompt space bank c will be 1. If the attempt to return space used by DC fails, c will be 2. Otherwise c will be 0 and all keys to DC {both with and without destroy rights} will be DK(0).

DC(DOMAINCREATOR__IDENTIFY_thing;S==>c;D,N)
{Order codes 5, 6, 7, 9, 10 & 11} If (S is a segment key with a segment keeper key and the no-call bit off and n is 4, or S is a meter key and n is 8) and S's keeper key is (a start key and m is 1, or a resume key and m is 2, or a domain key and m is 3) and the keeper's domain's brander was DC's brander, then DC(n+m;S==>c;D,N) returns a node key N to the node designated by S, D is a domain key to the keeper's domain, c is the databyte from S {or 0 if S is a meter key}. N has the same databyte as S. Otherwise c=-1 and N and D are DK(0). This function of the domain tool does not allow the tool holder to discover information that could otherwise be considered safely hidden.

On Mar 4 1985 order code 5 required 1300 microseconds on a 4341.

DC(DOMAINCREATOR__WEAKEN{=13};==>;WDC)
Returns a key WDC to DC without destroy rights.

DC(kt;==>c;) returns X'0D' in c promptly.

DC(kt+4 ==> c;)

If DC doesn't have destroy rights, c=kt+2.

Otherwise, this operation attempts to destroy the DC. c=0 if successful. c=1 if unsuccessful {because the bank that DC was made from has been destroyed} {and DC is useless}.

The following definitions can be found in MACLIBS PLIGATES and DOMAIN, member DOMCDEFS.
DOMAINCREATOR__CREATE_DOMAIN=0, DOMAINCREATOR__DESTROY_DOMAIN=1, DOMAINCREATOR__IDENTIFY_ENTRY=2, DOMAINCREATOR__IDENTIFY_EXIT=3, DOMAINCREATOR__DESTROY=4, DOMAINCREATOR__IDENTIFY_SEGMENT=5, DOMAINCREATOR__IDENTIFY_SEGMENT_WITH_EXIT_KEY_KEEPER=6, DOMAINCREATOR__IDENTIFY_SEGMENT_WITH_DOMAIN_KEY_KEEPER=7, DOMAINCREATOR__WEAKEN=13,
DOMAINCREATOR__DESTROY_CALLER=X'40000000'

{arcane}{nonref}Design Notes:
{arcane}{nonref}Design proposal: We want to have a weakened version of a DC so that a domain can destroy itself without interfering with DDT {i.e., without being able to get a strong key to itself}.

It would be useful to have an operation on a DC that takes a domain key to a domain, the bank from which that domain was built and severs all keys to that domain and returns a new domain key thereto. This is safe because all of the necessary authority is already present in the DC and its parameters. It would be efficient because the DC could ask the bank to sever the root node.

Let DCC be the domain creator creator. It is prompt.

DCC(0;PSB,M ==> c;DC) "Create DC"

PSB must be an official prompt space bank; if not, c will be 1. PSB is used to create at most four nodes and one page for a new domain creator DC. If space cannot be obtained, c will be 2. {Any space that was obtained is returned.} If some space created from PSB is zapped before the DCC call returns, it may return kt+1 in c, or it may not return at all {but DCC remains prompt}. If such space is zapped later, calls to the DC may do likewise.

The new domain creator will run under meter M.

If successful, c will be zero and DC will be the only key to a new domain creator whose brander is a key available only to DCC. DC has destroy rights.

DCC(1;DC ==> c;) "Identify DC"
If DC is not a domain creator created by the DCC, c is -1. Otherwise c is 0 if the DC has destroy rights and 1 if it doesn't.

DCC(kt;==>c;) returns X'010D' in c.