Library Template and Library Directory
A Library Template is built by a Compiler for a program that declares Entrypoints which are in an external Library to which it will Link.
A Library Directory is built by a Compiler for a program which Exports Entrypoints and will Freeze to become a Library.
This is the general structure of a LibraryTemplate and a Library Directory. The structure of a Library Template and a Library Directory are almost the same, and any differences are noted in the text.
| Header Area |
| Stack Reference Area |
| Objects Area |
| Types Area |
| Names Area |
| Attributes Area |
| UseInfo Area |
| Free Area |
This description is for a Level 6 Library Template on MCP 5.0. It only discusses the fields used by a Compiler.
Library Template Header Area
The Header Area contains Level information and indexes to the other Areas. Many of the fields are only used by the MCP when the Template is touched.
L_HeaderAreaSizeInWordsV = 15.
| Library Template Header Area | ||||
|---|---|---|---|---|
| Word | Field | Name | Values | Description |
| 0 | L_StatusV | |||
| [23:8] | L_LevelF | L_Template3V = 3 L_Template6V = 6 |
A Level 4 Template has the same
layout as a Level 3 Template, but contains Imported or Exported Data
(42.1).
A Level 5 Template allows a WAIT on an imported Event (47). |
|
| [6:1] | L_OneWayF | |||
| [5:2] | L_TypeF | L_ServerV = 0 L_Single_CLEV = 1 L_Multi_CLEV = 2 L_Win32_DLLV = 3 |
||
| [3:4] | L_LinkClassF | L_UserV = 0 L_SupportV = 1 |
||
| 1 | [31:16] | L3_FreeIndexF | This is the index of the Free Area in Level 3 Templates, which has been moved to Word 8 for Level 6 Templates. | |
| [15:16] | L_UseInfoIndexF | Word Index of the MCP UseInfo Area | ||
| 2 | [47:16] | L_StackRefIndexF | Word Index of the Stack Reference Area for APPROVAL and CHANGE procedures. | |
| [31:16] | L_ImportsIndexF | Word Index of Imported Objects Area. These are the Objects declared to belong to a Library, and for which the Compiler generates a Library Template. | ||
| [15:16] | L_ExportsIndexF | Word Index of Exported Objects Area. These are the Objects which are Exported from the program, and for which the Compiler generates a Library DirectoryTemplate. | ||
| 3 | [47:16] | L_TypesIndexF | Word Index of the Types Area. It contains the Type descriptions of the Objects and their Parameters. | |
| [31:16] | L_NamesIndexF | Word Index of the Names Area, which contains the names of the Objects. | ||
| [15:16] | L_AttributesIndexF | Word Index of the Attributes Area, which contains the Attributes for a Library, such as TITLE and LIBACCESS. | ||
| 4 | 0 | |||
| 5 | 0 | |||
| 6 | 0 | |||
| 7 | 0 | |||
| 8 | [19:20] | L_FreeIndexF | Word Index of the Free Area used by the MCP. | |
| 9 | 0 | |||
| 10 | 0 | |||
| 11 | 0 | Only Level 6 and later Templates have Words 11..14 | ||
| 12 | 0 | |||
| 13 | 0 | |||
| 14 | 0 | |||
Library Template Stack Reference Area.
The Stack Reference Area is located at the Word given by Template[1].L_StackRefIndexF.
This area maintains stack references (Lex Level and Displacement) to any CHANGE or APPROVAL procedures for a Library.
L_StackRefAreaSizeInWordsV = 6.
| Library Template Stack Reference Area | ||||
|---|---|---|---|---|
| Word | Field | Name | Values | Description |
| 0 | [15:16] | L_SizeF | 6 | L_StackRefAreaSizeInWordsV |
| 1 | [11:12] | L_TemplateOffsetF | The Stack Displacement of the Library Template. | |
| 2 | 0 | |||
| 3 | L_LinkEventV | |||
| [47:24] | L_ApprovalF | Composite Field | ||
| [47:4] | L_Approval_LexLevelF | |||
| [43:4] | 0 | |||
| [39:16] | L_Approval_OffsetF | |||
| [23:24] | L_ChangeF | Composite Field | ||
| [23:4] | L_Change_LexLevelF | |||
| [19:4] | 0 | |||
| [15:16] | L_Change_OffsetF | |||
| 4 | ||||
| 5 | ||||
Library Template Objects Area.
The Objects Area definition is used for both Imported Objects and Exported Objects.
The Imported Objects are located at the Word given by Template[2].L_ImportsIndexF.
The Exported Objects are located at the Word given by Template[2].L_ExportsIndexF.
The size of the area depends on the number of objects, and is stored in Word 0. The size of the area includes the Size Word.
| Library Template Objects Area | ||||
|---|---|---|---|---|
| Word | Field | Name | Values | Description |
| 0 | ||||
| [15:16] | L_SizeF | The total number of words in the area, including this word. | ||
| 1..(L_SizeF-1) | 2 Word Object Descriptions | |||
The Objects are sorted in ascending order by Name.
| Library Template Object | ||||
|---|---|---|---|---|
| Word | Field | Name | Values | Description |
| 0 | [47:4] | L_ProvisionF | L_DirectV = 0 L_IndirectV = 1 L_ByCallingV = 2 L_DynamicV = 3 |
|
| [43:8] | L_NameLengthF | Length of Object Name in Bytes | ||
| [35:20] | L_NameIndexF | Byte Index of Object Name from the start of the Library Template Names Area | ||
| [15:16] | L_TypeIndexF | Index of the Type Tree | ||
| 1 | [47:16] | L_IndirObjF | Frame offset in Indirect Library | |
| [25:2] | L_AccessModeF | L_NoAccessV = 0 L_ReadOnlyV = 1, L_ReadWriteV = 2 |
||
| [19:4] | L_ObjectLinkClassF | |||
| [15:16] | L_DisplacementF | |||
The Exported Objects described in a Library Directory have a sentinel Object with the name 4"FF". A Library Template does not have a sentinel Object.
Library Template Types Area.
The Types Area is located at the Word given by Template[3].L_TypesIndexF. It contains entries which describe the types and parameters of the library objects.
| Library Template Types Area | ||||
|---|---|---|---|---|
| Word | Field | Name | Values | Description |
| 0 | ||||
| [15:16] | L_SizeF | The total number of words in the area, including this word. | ||
| 1..(L_SizeF-1) | Type Definitions | |||
See BuildTypeDescription in Algol at 82050000.
Library Template Names Area
The Names Area is located at the Word given by Template[3].L_NamesIndexF. It contains the Ebcdic names of the Objects.
| Library Template Names Area | ||||
|---|---|---|---|---|
| Word | Field | Name | Values | Description |
| 0 | ||||
| [15:16] | L_SizeF | The total number of words in the area, including this word. | ||
| 1..(L_SizeF-1) | Ebcdic Names. The Sentinel name for Exported Objects is 4"FF". | |||
Library Template Attributes Area
The Names Area is located at the Word given by Template[3].L_NamesIndexF. It contains the Ebcdic names of the Objects.
| Library Template Attributes Area | ||||
| Word | Field | Name | Values | Description |
|---|---|---|---|---|
| 0 | ||||
| [15:16] | L_SizeF | The total number of words in the area, including this word. | ||
| 1 | 0 | This word is referred to as the VALUE Word, and is 0. | ||
| 2..(L_SizeF-2) | A list of Library Attribute
entries, terminated by a NULL Byte. The Last Word is filled with NULLs to
the Word Boundary.
An extra, Lib_Template_Attributes_Extra = 5, null Words are allocated at the end of the Attributes Area. |
|||
There are several different formats for attribute definitions,
- Standard String attributes -
48"02"<1 byte attno><standard form name>. For example,
TITLE and FUNCTIONNAME.
- Long string attributes -
48"02"<attno><2 byte length><text>. These are
detected by their Attribute Number. For example, LIBPARAMETER.
- Scalar Attributes - <1 byte attlength><1byte attno><attvalue>. The <attvalue> size is given by <attlength> minus 2.
| Name | Attribute No. | Format | Comments |
|---|---|---|---|
| INTNAME | 48"00" | 48"0200"<standard form name> | The <standard form name> has only 1 name, and no usercode or familyname. |
| TITLE | 48"01" | 48"0201"<standard form name> | |
| LIBPARAMETER | 48"02" | 48"0202"<2 byte length><text> | |
| FUNCTIONNAME | 48"03" | 48"0203"<standard form name> | |
| LIBACCESS | 48"04" | 48"0304"<libaccess code> | A <libaccess code> is
returned by the VALUE Function using one of these Mnemonics, BYTITLE (1) BYFUNCTION (2) BYINITIATOR (3) |
| TRUSTED | 48"05" | ||
| LINKCLASS | 48"06" | A <linkclass code> is
retuned by the VALUE Function using one of these Mnemonics, MCPLIB (1) MCSLIB (2) ENVLIB (3) PPLIB (4) COMPILERLIB (5) MAXCLASS (15) |
|
| LIBRARYDEF | 48"08" | Not yet implemented. |
Library Template UseInfo Area
The UseInfo Area is located at the Word given by Template[1].L_UseInfoIndexF.
L_UseInfoAreaSizeInWordsV = 3.
This area is used by the MCP and is set to 0 by the Compilers.
Library Template Free Area
The Free Area is located at the Word given by Template[8].L_FreeIndexF.
L_FreeAreaSizeInWordsV = 10.
This area is used by the MCP and is set to 0 by the Compilers.