Summary: Under the C mapping how do you allocate storage for a basic type
you wish to place in an any.

Consider inserting a long into an Any.

Do you do this: solution 1

any->_type = TC_long;
any->_value = CORBA_alloc(sizeof(CORBA_long));

or this: solution 2

any->_type = TC_long;
any->value = CORBA_long_alloc();

One vendor argues that the text below supports solution 2. However
as a long is not a constructed type solution 1 seems more natural.

>From "17.8 Mapping Considerations for Constructed Types" of CORBA 2.1
specification:

"For types whose parameter passing modes require heap allocation,
an ORB implementation will provide allocation functions. These types
include variable-length struct, variable-length union, sequence, any,
string, wstring and array of a variable-length type. The return value
of these allocation functions must be freed using CORBA_free(). For
one of these listed types T, the ORB implementation will provide
the following type-specific allocation function:

T *T__alloc(); /* C */"

urgent resolution, issue resolved

Summary: Nothing defines what an "objref_ptr" is. This was presumably pasted in from C++ mapping which has a T_ptr concept. Stop using this term in the C mapping or define it

Fixed in CORBA 2.2 editing process

Summary: Additional Commentary:

In tset/c/hdr/DII/ORB/send_multiple_requests.c,
VSOrb 1.1.0 test examines our orb on the assumption that
send_multiple_requests() is defined like the following.

CORBA_Status CORBA_send_multiple_requests(
CORBA_ORB orb,
CORBA_Request reqs[],
CORBA_long count,
CORBA_Flags invoke_flags,
CORBA_Environment *env
);

But, according to section 4.3.2 of CORBA 2.1 specification,
send_multiple_requests() is defined like the following.

/* C */
CORBA_Status CORBA_send_multiple_requests(
CORBA_Request reqs[],
CORBA_Environment *env,
CORBA_long count,
CORBA_Flags invoke_flags
);

Section C - Interpretation Responses

The Open Group Initial Response:
An interpretation from OMG is required to determine whether Section
4.3.2 or Section 17.17 of CORBA 2.1 is definitive.

Consultants Initial Response:
We believe Section 4.3.2 is incorrect according to the general
C mapping rules (as are many of the other examples). We are
following rules defined in Section 17.17 which states that every
function signature takes the object as the first parameter and an
Environment object as the last parameter.

Interpretations Subgroup Responses:

urgent resolution....issue closed

Summary: Section 14.11. Para 6 indicates error to set _length or _maximum member larger than specified bound. Say "If the _length and _maximum members are set to a value larger than specified...."

replace sentence

Summary: Section 14.5. ISO C permits declaration of anonymous structures when type is being defined. From a coding style perspective it"s better to require use of defined type names

close

Summary: Section 14.15: Bullet 2 indicates that last parameter to each operation is an output parameter..Inconsistent with lead sentence, CORBA 1.2, and not reflectedin rest of doc.

Fixed by Portability submission

Summary: Section 14.13: Para 6 Change "For an array T..." to "An array T..."

Fixed in CORBA 2.2 editing process

Summary: Editorial issue: The definition on page 14-15 is given as char* CORBA_string_alloc(CORBA_unsigned_long_len); The return type should be "CORBA_char*".

Fixed in CORBA 2.2 editing process

Summary: C signature for example4_op5 as well as CORBA_BOA_set_exception have the environment parameter in the wrong place

Fixed by Portability Submission

Summary: Section 14.11: It"s not clear how a portable application could know value of bound of sequence. It"s specified in PIDL but is not represented in generated C header

add sentence

Summary: Paragraph refers to "DIR". This term has not been recently defined in the specification.

Fixed in CORBA 2.2 editing process

Summary: Order of arguments to C Language mapped operations seems to have changed from CORBA 1.2. Order must remain the same. Order must be used consistently throughout this specification .

Fixed by Portability submission

Summary: Example CORBA_ORB_object_to_string function shows CORBA 1.2 function argument ordering. This is inconsistent with text in sect. 14.15. Spec must be internally consistent.

Fixed by Portability submission

Summary: CORBA_exception_id() returns a pointer to the character string indentifying the exception. It would be nice to explicitly say that this is the same string defined in 14.14.

Replace sentence to clarify

Summary: It would be useful if CORBA_string_alloc() took an "optional" second argument which would be the string value to initialize the new string to, since ANSI C does not have strdup().

Close with no change

Summary: In section 14-10 of the C mapping, it says that an ORB can use a struct to hold a union. Doesn"t this cause portability problems?

Close with no change

Summary: Section 14.3 of the C mapping says that interface definitions may not occur within the scope of module declarations. Doesn"t it mean "within the scope of another interface definition"?

resolved and closed

Summary: Par. 14.1.8 indicates that ORB may handle calls to pseudo-objects via DII specially. This spec. should indicate that DII can"t be portably used for pseudo-object references.

close – paragraph is deleted

Summary: Entire section should not be here.It"s relevant to all potential language mappings. It should be moved to an appendix, since it is not a normative part of the specification

delete section

Summary: Who owns the parameters "exceptname" and "param" to CORBA_BOA_set_exception? Shouldn"t that routine take a second CORBA_Environment parameter to signal errors in its operation?

POA update eliminated conditions - close

Summary: On p. 14-24, the example of CORBA_ORB_object_to_string seems to have the CORBA_environment parameter in an unexpected position. Is this intentional? And what about the example on 14-28?

Fixed by Portability submission

Summary: Section 14.11 of the C mapping introduces a release flag hidden inside the C struct; however, that struct is completely specified and leaves no bit for that flag. How does this work?

Close with no change

Summary: Sun wants to ensure that DII interface permits implementations that support invocations without consulting the interface repository as intended by CORBA.

close

Summary: Section 14.14 calls for a string literal which "uniquely identifies this exception type", but does not specify any rules for generating such identifiers.

Close with no change

Summary: The C mapping allocation procedures (T__alloc()) don"t allow for malloc"ing space for both the header struct and the values in one call.

Close with no change

Summary: The fact that a sequence of longs is to be mapped into a struct is very confusing.

Close with no change

Summary: There seems to be no provision for the possibility of C keywords appearing in IDL.

resolved and closed

Summary: The C mapping advises avoiding the indiscriminate use of underscores in identifiers. To whom is this addressed? Should it be a more general restriction?

resolved

Summary: In PIN4O.00001 OMG have ruled that the content of an any is a
pointer to the type. So a long in an Any looks like this;

any ----> long

But what about strings? As this type includes a pointer part
itself the above rules would make the following appear to be the
conformant case;

any----> ptr to string -----> string : option 1

Having a pointer to a pointer is a bit unwieldy but appears to follow
the rules. Collapsing this to simply a pointer to the str thus;

any----> string : option 2

is more natural for programmers but ambiguous within the spec.

We would like to know which of these two options is correct.

Section C - Interpretation Responses

The Open Group Initial Response:
This request is being sent for review by OMG. We request that OMG
rule which of the two options is correct or whether both are equally
so.

Consultants Initial Response:
We recommend this request be sent to OMG for a binding interpretation.

We recommend a PIN be granted to clarify the requirements for branding
irrespective of which of the two options OMG selects.

urgent resolution, issue closed

Summary: What if user calls T_allocbuf for a bound sequence with a length that doesn"t match sequence constraint?Does this go undetected?. A related issue is issue # 108

Summary: Sequence buffers are allocated seperately from sequence which contain them, they can be released separately as well. Is this the job of the omnipotent CORBA_free?

Summary: Mapping for IDL typedefs was dropped between CORBA 1.2 and 2.0. It should explicitly stated. Restoring text from 1.2 mapping is probably sufficient

Summary: Loose specification of the #define generated for an exception id: Specification by example is never a good idea. The specification should be more explizit.

Summary: Generate a Seq_releasebuf function for sequence Seq of type T to perform any buffer internal release. Function is called by Seq_freebuf prior to free buffer pointer acc. to release flag

Summary: Generate a Seq_initbuf function to initialize a buffer for sequence Seq of type T. Seq__allocbuf allocates a buffer and calls seq_initbuf to initialize the allocated buffer

Summary: Generate pairs of (T_init, T_alloc) functions for any type T (with descriptions described in issue # 309 concerning T_alloc)

Summary: Define 2 functions, CORBA_exception_init and CORBA_systemException_init to initialize respectively user-defined exceptions and system exceptions to be raised

Summary: Table 22,p 14-20 of C mapping lists argument passing cases. In both cases(3+6) the value is either an out parameter or return value. How to handle CORBA_free as caller or callee

Summary: generate pairs of (E_init, E_alloc) and (E_release, E_free) functions for exception E with behavior similar to the corresponding functions defined for any type T.

Summary: State as undefined the behavior of a sequence as long as its Seq_init function (as specified in issue # 322) has not been called this function initializing the release flag.

Summary: Generate pairs of (T_release, T_free) functions for any type T T_release performs any internal memory release T_free calls T_release and frees the pointer argument

Summary: Define the type of system exceptions to be typedef definitions of a generic system exception type CORBA_SystemException

Summary: Para describes strategy an implementation will use for determining an exception TypeCode. Information not relevant to application developer. Mark as guidance to Implementor.

Summary: Para indicates that all the parameter memory is freed as appropriate when DIR returns. Who frees memory? If DIR frees memory, then change the wording as appropriate.

Summary: Section D.11 presents C mapping for sequence. For performance reasons, Sun prefers to embed the release flag in the sequence.

Summary: In the definition of CORBA_ORB_init environment parameter comes last and it uses env instead of ev. Same inconsitency in CORBA_ORB_list_initial_services/CORBA_ORB_list_initial_references

Summary: vec10 and CORBA_sequence_long: are these distinct types?Would they have distinct typecodes and distinct entries in the Interface Repository?

Summary: Spec contains mutually inconsistent example (p 14-11 and 14-13. P 14-13 suggests that C structure MUST be named CORBA_sequence_long instead and must be enclosed in #ifdef...#endif

Summary: When sequence occurs as anonymous (local) type in a struct,union,etc, how should this be treated?

Summary: Are we supposed to declare and define allocators for new sequence Type? What is acceptable, required, forbidden (in terms of functions)?

Summary: Sec 14.25.2: It"s not clear what happens if CORBA_BOA_set_exception is called more than once for a given object invocation. This should be specified.

Summary: Section D.7 describes the mapping for CORBA_any. Sun would like to replace current C mapping for Any with opaque type, i.e conforming applications may not access members of CORBA_any struct

Summary: In C mapping what is representation of "string" in _value field of an any? "char *" or "char **"? "char **" seems to be more applicable-usage requires an "_alloc" function

Summary: The spec mentions 2 allocation functionsfor sequences of "T". These should better be inside the same (or similar) #ifdef...#endif as the struct typedef

Summary: It refers to a "third case", but there are no cases described, and there are only 2 examples. What are the cases this paragraph refers to?

Summary: There is very probably a small error in the C language specification.
Below is what I wrote to the mailing list concerned with building the ORBit ORB. It
was confirmed by one of the main coders behind ORBit.

> This is something else, but I was more confused because the OMG "C language
> mapping" spec at page 19-39 really seems to contain an error.
> In that example, they also create an application specific servant structure called
> AppServant, and they set the finalizer using
>
> AppServant my_servant = ...
>
> my_servant.epv._base_epv.finalize = my_finalizer_func;
>
> That should really have been (at least, that"s what I think):
>
> my_servant.base.vepv._base_epv.finalize = my_finalizer_func;
>
> I hope you agree with me there, or else I"m probably getting out of touch with C.

Summary: I currently implement a subset of CORBA 2.0. Not CORBA-compliant in terms of C-mapping for arguments to pseudo-objects and real objects. Give clear statement on argument order for real objects

Summary: Example foo::bar on page 14-17 has fixed array out parameter. Mapping shown on this page doesn"t agree with tables 20 and 21.

Summary: Sec 14.11 specifies generation of a buffer allocator for each sequence type of form T* sequence_T_allocbuf (CORBA_unsigned_long_len); very difficult to implement correctly.

Summary: Section 14.28.1, 14.28.2, 14.29: CORBA_string is not defined anywhere in the code sample. These should be typedefed as CORBA_char * or char *

Summary: Section 14.3: Reference is made to CORBA_OBJECT_NIL but there is no defined value for this. A value must be explicitly defined and typed

Summary: The first para of section 14.17 seems to have crept back after a deletion in a n earlier draft- it shouldn"t since it generalizes things (wrongly) which are properly described later

Summary: Spec. should be clear that the pointer passed in out parameters by caller should be uninitialized. This clarification should be in case (3) and (6) of Table 22

Summary: Mapping should be explicit about how release flag interacts with inout, out, and return parameter. There probably is arelated C++ issue

Summary: Sect.14.23: Section indicates that ORBs may restrict the scope of legal operations on pseudo-objects. Minimal subset of operations should be defined so port. applications know what to rely on.

Summary: Section 14.22: Al IDL compilers will generate a C language header. Does that mean that the C Language is required to be supported by all CORBA implementations?

Summary: Information on implementation strategies for pseudo-objects is not relevant to application portability. It should be removed or appropriately annotated as guidance for ORB implementors.

Summary: In case 5 of table 22 in section 14.19, what is the specified behavior if the release flag is FALSE, but the value to be returned is longer than the value specified?

Summary: Section 14.19: Asteriks in table are meant to indicate that item is a C Language pointer. They should not be subscribed.

Summary: Generate T__alloc functions for any type T except interfaces: no function, any: CORBA_any_alloc string: CORBA_string_alloc

Summary: When must this be done? always, whenever the release flag is TRUE, whenever the sequence elements contain secondary storage, whenever it is an out, inout, or return

Summary: Generate a E_free function dual to Ealloc for exception E. /* C API / void E_free (E);

Summary: Generate string literal for exceptions as the stringification of the macro name e.g.for exception E: /*C code generation */ #define ex_E "ex_E"

Summary: Generate a pair of (Seq_allocbuf, Seq_freebuf) functions, for sequence Seq of type T to manage resource of buffer sequences: Seqallocbuf and Seq_freebuf

Summary: The proposal is to state as undefined the behavior of a sequence as lon as its release flag has not been initialized

Summary: Define the _minor field of system exceptions to be of type CORBA_ExceptionMinor

Summary: Reserve the CORBA_exception_id function for user-defined exceptions only.

Summary: Map sequence type names and sequence element type names enclosed within a scope according to the encoding scheme described as follows (/archives/issues/issue314)

Summary: Deprecate use of CORBA_free and generate T_free functions for any type T instead. Specification of T_free is current spec for CORBA_free suitable for type T

Summary: Add release flag to generated C structure and map IDL sequence type from following definition (/archives/issues/issue311)

Summary: Define a library function CORBA_Environment_init to initialize the non-opaque fields of CORBA_Environment (see file)

Summary: Why is it not CORBA_sequence_CORBA_long? What is the precise rule by which these names are constructed?