const GateProcessSupport_GETREFCOUNT_FAILED |
 |
Status returned by getReferenceCount when there is an error
#define GateProcessSupport_GETREFCOUNT_FAILED (Int)-1
const GateProcessSupport_Q_BLOCKING |
 |
Blocking quality
#define GateProcessSupport_Q_BLOCKING (Int)1
DETAILS
Gates with this "quality" may cause the calling thread to block;
i.e., suspend execution until another thread leaves the gate.
const GateProcessSupport_Q_PREEMPTING |
 |
Preempting quality
#define GateProcessSupport_Q_PREEMPTING (Int)2
DETAILS
Gates with this "quality" allow other threads to preempt the thread
that has already entered the gate.
config GateProcessSupport_A_POSIX_Error // module-wide |
 |
extern const Assert_Id GateProcessSupport_A_POSIX_Error;
config GateProcessSupport_A_invalidKey // module-wide |
 |
Asserted in GateProcess_create
extern const Assert_Id GateProcessSupport_A_invalidKey;
config GateProcessSupport_E_POSIX_Error // module-wide |
 |
extern const Error_Id GateProcessSupport_E_POSIX_Error;
config GateProcessSupport_L_create // module-wide |
 |
extern const Log_Event GateProcessSupport_L_create;
config GateProcessSupport_L_extant // module-wide |
 |
extern const Log_Event GateProcessSupport_L_extant;
config GateProcessSupport_perms // module-wide |
 |
unix-style RW perms for the underlying sem
extern const Int GateProcessSupport_perms;
GateProcessSupport_query() // module-wide |
 |
Runtime test for a particular gate quality
Bool GateProcessSupport_query(Int qual);
ARGUMENTS
qual
constant describing a quality
RETURNS
Returns TRUE if the gate has the given quality,
and FALSE otherwise, which includes the case when the gate does not
recognize the constant describing the quality.
Module-Wide Built-Ins |
 |
// Get this module's unique id
Bool GateProcessSupport_Module_startupDone();
// Test if this module has completed startup
// The heap from which this module allocates memory
Bool GateProcessSupport_Module_hasMask();
// Test whether this module has a diagnostics mask
Bits16 GateProcessSupport_Module_getMask();
// Returns the diagnostics mask for this module
Void GateProcessSupport_Module_setMask(Bits16 mask);
// Set the diagnostics mask for this module
Instance Object Types |
 |
typedef struct GateProcessSupport_Object GateProcessSupport_Object;
// Opaque internal representation of an instance object
// Client reference to an instance object
typedef struct GateProcessSupport_Struct GateProcessSupport_Struct;
// Opaque client structure large enough to hold an instance object
// Convert this instance structure pointer into an instance handle
// Convert this instance handle into an instance structure pointer
Instance Config Parameters |
 |
typedef struct GateProcessSupport_Params {
// Instance config-params structure
// Common per-instance configs
Int key;
// globally unique key for SysV-style semaphore
} GateProcessSupport_Params;
// Initialize this config-params structure with supplier-specified defaults before instance creation
config GateProcessSupport_key // instance |
 |
globally unique key for SysV-style semaphore
Instance Creation |
 |
// Allocate and initialize a new instance object and return its handle
// Initialize a new instance object inside the provided structure
ARGUMENTS
params
per-instance config params, or NULL to select default values (target-domain only)
eb
active error-handling block, or NULL to select default policy (target-domain only)
DETAILS
This function creates a new GateProcess object which is initialized to
count. All gates created with the same key reference the same
underlying synchronization object and work between processes. The
underlying synchronization object should be automatically deleted when
all references to it have been deleted, and the reference count should
An implementation for a platform on which this is technically impossible
(e.g. an operating system that does not support multiple processes) may
provide a 'toy' implemenation with behavior matching that of
IGateProcessSupport.
Instance Deletion |
 |
// Finalize and free this previously allocated instance object, setting the referenced handle to NULL
// Finalize the instance object inside the provided structure
GateProcessSupport_enter() // instance |
 |
Enter this gate
ARGUMENTS
handle
handle of a previously-created GateProcessSupport instance object
DETAILS
Each gate provider can implement mutual exclusion using different
algorithms; e.g., disabling all scheduling, disabling the scheduling
of all threads below a specified "priority level", suspending the
caller when the gate has been entered by another thread and
re-enabling it when the the other thread leaves the gate. However,
in all cases, after this method returns that caller has exclusive
access to the data protected by this gate.
A thread may reenter a gate without blocking or failing.
RETURNS
Returns a "key" that is used to
leave this gate; this
value is used to restore thread preemption to the state that
existed just prior to entering this gate.
GateProcessSupport_getReferenceCount() // instance |
 |
Get the number of processes with references to this Gate
ARGUMENTS
handle
handle of a previously-created GateProcessSupport instance object
err
Pointer to Error.Block
RETURNS
Returns the number of processes that possess a
reference to this gate, or GETREFCOUNT_FAILED if an
error occured.
A 'toy' implementation should always return 0.
GateProcessSupport_leave() // instance |
 |
Leave this gate
ARGUMENTS
handle
handle of a previously-created GateProcessSupport instance object
key
the value returned by a matching call to
enter
DETAILS
This method is only called by threads that have previously entered
this gate via
enter. After this method returns, the
caller must not access the data structure protected by this gate
(unless the caller has entered the gate more than once and other
calls to
leave remain to balance the number of previous
calls to
enter).
Instance Convertors |
 |
// unconditionally move one level up the inheritance hierarchy
// conditionally move one level down the inheritance hierarchy; NULL upon failure
// unconditionally move 2 levels up the inheritance hierarchy
// conditionally move 2 levels down the inheritance hierarchy; NULL upon failure
// unconditionally move 3 levels up the inheritance hierarchy
// conditionally move 3 levels down the inheritance hierarchy; NULL upon failure
Instance Built-Ins |
 |
Int GateProcessSupport_Object_count();
// The number of statically-created instance objects
// The handle of the i-th statically-created instance object (array == NULL)
// The handle of the first dynamically-created instance object, or NULL
// The handle of the next dynamically-created instance object, or NULL
// The heap used to allocate dynamically-created instance objects
// The label associated with this instance object
// The name of this instance object
const GateProcessSupport.GETREFCOUNT_FAILED |
 |
Status returned by getReferenceCount when there is an error
XDCscript usage |
meta-domain |
const GateProcessSupport.GETREFCOUNT_FAILED = -1;
C SYNOPSIS
const GateProcessSupport.Q_BLOCKING |
 |
Blocking quality
XDCscript usage |
meta-domain |
const GateProcessSupport.Q_BLOCKING = 1;
DETAILS
Gates with this "quality" may cause the calling thread to block;
i.e., suspend execution until another thread leaves the gate.
C SYNOPSIS
const GateProcessSupport.Q_PREEMPTING |
 |
Preempting quality
XDCscript usage |
meta-domain |
const GateProcessSupport.Q_PREEMPTING = 2;
DETAILS
Gates with this "quality" allow other threads to preempt the thread
that has already entered the gate.
C SYNOPSIS
config GateProcessSupport.A_POSIX_Error // module-wide |
 |
XDCscript usage |
meta-domain |
msg: "A_POSIX_Error: a POSIX function returned failure"
};
C SYNOPSIS
config GateProcessSupport.A_invalidKey // module-wide |
 |
Asserted in GateProcess_create
XDCscript usage |
meta-domain |
msg: "A_invalidKey: params key has not been set"
};
C SYNOPSIS
config GateProcessSupport.E_POSIX_Error // module-wide |
 |
XDCscript usage |
meta-domain |
msg: "E_POSIX_Error: a POSIX function returned failure, errno is %d"
};
C SYNOPSIS
config GateProcessSupport.L_create // module-wide |
 |
XDCscript usage |
meta-domain |
msg: "--- GateProcess(%d) DNE, creating"
};
C SYNOPSIS
config GateProcessSupport.L_extant // module-wide |
 |
XDCscript usage |
meta-domain |
msg: "--- GateProcess(%d) already exists, incrementing reference count"
};
C SYNOPSIS
config GateProcessSupport.perms // module-wide |
 |
unix-style RW perms for the underlying sem
XDCscript usage |
meta-domain |
GateProcessSupport.perms = Int 0666;
C SYNOPSIS
metaonly config GateProcessSupport.common$ // module-wide |
 |
Common module configuration parameters
XDCscript usage |
meta-domain |
DETAILS
All modules have this configuration parameter. Its name
contains the '$' character to ensure it does not conflict with
configuration parameters declared by the module. This allows
new configuration parameters to be added in the future without
any chance of breaking existing modules.
metaonly GateProcessSupport.queryMeta() // module-wide |
 |
Configuration time test for a particular gate quality
XDCscript usage |
meta-domain |
GateProcessSupport.queryMeta(Int qual) returns Bool
ARGUMENTS
qual
constant describing a quality
RETURNS
Returns TRUE if the gate has the given quality,
and FALSE otherwise, which includes the case when the gate does not
recognize the constant describing the quality.
Instance Config Parameters |
 |
XDCscript usage |
meta-domain |
var params = new GateProcessSupport.Params;
// Instance config-params object
params.key = Int -1;
// globally unique key for SysV-style semaphore
config GateProcessSupport.key // instance |
 |
globally unique key for SysV-style semaphore
XDCscript usage |
meta-domain |
var params = new GateProcessSupport.Params;
...
params.key = Int -1;
C SYNOPSIS
Instance Creation |
 |
XDCscript usage |
meta-domain |
var params =
new GateProcessSupport.
Params;
// Allocate instance config-params
params.config = ...
// Assign individual configs
var inst = GateProcessSupport.create(params);
// Create an instance-object
ARGUMENTS
params
per-instance config params, or NULL to select default values (target-domain only)
eb
active error-handling block, or NULL to select default policy (target-domain only)
DETAILS
This function creates a new GateProcess object which is initialized to
count. All gates created with the same key reference the same
underlying synchronization object and work between processes. The
underlying synchronization object should be automatically deleted when
all references to it have been deleted, and the reference count should
An implementation for a platform on which this is technically impossible
(e.g. an operating system that does not support multiple processes) may
provide a 'toy' implemenation with behavior matching that of
IGateProcessSupport.