1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
--Copyright: Matra Datavision 1992,1993
-- File: OSD_MailBox.cdl
-- Created: Thu 19 March 1992
-- Author: Stephan GARNAUD (ARM)
-- <sga@sparc4>
class MailBox from OSD
---Purpose: Establishes a mailbox with VMS-like-features and with
-- asynchronous functions.
-- The mail boxes are used to communicate asynchronously
-- between processes.
-- Basically MailBox facilities provide tools to communicate
-- between a client process and a server process.
-- The client process puts data/requests into the mail-box and
-- the server process gets these data/requests. In this context
-- client and server must run on the same machine.
-- Warning: On VMS, you need TMPMBX privilege.
uses Function, SharedMemory, Error, AsciiString from TCollection
raises ConstructionError, NullObject, OSDError, ProgramError
is
Create returns MailBox;
---Purpose: To be used with 'Open'.
-- It just allocates room for 'myName'.
-- This is for a client process.
---Level: Advanced
Create (name : AsciiString ; Size : Integer ; Async_function : Function)
returns MailBox
---Purpose: Instantiates MailBox object with a name, size required
-- and a function to read mail boxes asynchronously.
-- Each process working with the same MailBox must use
-- a common known access : the mail-box's name.
--
-- This is for a server process.
-- Raises ConstructionError when the name is not composed by
-- characters in range of ' ' .. '~'.
-- Raises NullObject when Async_function is a null function
-- pointer
-- Raises ProgramError when Size has a negative or null value.
---Level: Advanced
raises ConstructionError, NullObject, ProgramError;
Build (me : in out) is static;
---Purpose: Builds (physically) <me> into system.
-- <me> is created and ready to run.
-- This can be seen as an asynchronous server.
---Level: Advanced
Open (me: out ; name : AsciiString ; Size : Integer)
---Purpose: Opens mail box, and is ready to communicate with an
-- already created mailbox.
-- Raises NullObject when the name is a null string.
-- Raises ConstructionError when the name contains characters not
-- in range of ' '...'~'.
-- Raises ProgramError when the mail box has a null size.
-- This can be seen as a client.
---Level: Advanced
raises ConstructionError, NullObject, ProgramError is static;
Delete (me: out)
---Purpose: Removes the mail box from system.
-- This is used only by server process !
-- Raises ProgramError when the mail box is already deleted.
---Level: Advanced
raises ProgramError is static;
Write (me : in out; Message : AsciiString ; Length : Integer)
---Purpose: Writes a message of specified length into mail box.
-- <Message> is used as a buffer, not as a common string.
-- So this can be not null terminated like a 'char *'.
-- This is why <Length> is useful.
-- Raises ProgramError when the length of the data is either
-- negative or zero.
--
---Level: Advanced
raises ProgramError is static;
Failed (me) returns Boolean is static;
---Purpose: Returns TRUE if an error occurs
---Level: Advanced
Reset (me : in out) is static;
---Purpose: Resets error counter to zero
---Level: Advanced
Perror (me : in out)
---Purpose: Raises OSD_Error
---Level: Advanced
raises OSDError is static;
Error (me) returns Integer is static;
---Purpose: Returns error number if 'Failed' is TRUE.
---Level: Advanced
fields
myId : Integer; -- Mail box Identification
myName : AsciiString; -- Name of mail box
mySize : Integer; -- Size of data area
myFunc : Function; -- AST like function
myError: Error;
end MailBox from OSD;
|
