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The scl_struct_sized pragma is one of the [[SCL_Pragmas#Qualification|Qualification]] pragmas. The scl_struct_sized pragma identifies a particular struct or pointer-to-struct as a sized structure. A sized structure typically has bytes allocated past its type definition.
The scl_struct_sized pragma is one of the [[SCL_Pragmas#Qualification|Qualification]] pragmas. The scl_struct_sized pragma identifies a particular struct or pointer-to-struct as a sized structure. A sized structure typically has bytes allocated past its type definition.
 
= STRIDE Versions =
Available in STRIDE 3.0.0103 (StoneSteps Tower 3) and later versions
== Syntax ==
== Syntax ==
  #pragma scl_struct_sized(type-name, max-size)
  #pragma scl_struct_sized(type-name, max-size)

Revision as of 18:07, 5 November 2008

The scl_struct_sized pragma

The scl_struct_sized pragma is one of the Qualification pragmas. The scl_struct_sized pragma identifies a particular struct or pointer-to-struct as a sized structure. A sized structure typically has bytes allocated past its type definition.

STRIDE Versions

Available in STRIDE 3.0.0103 (StoneSteps Tower 3) and later versions

Syntax

#pragma scl_struct_sized(type-name, max-size)

Parameters Type Description
type-name Struct,
Pointer
Specifies a structure type (or a pointer to such type) that is to be sized (allocated bytes beyond its type definition).

The following restrictions apply:

  • The structure type may not be pointed to by a sized pointer.
  • The structure type may not be a member of any other structure or union.
  • The structure type may not be passed as a function parameter.
  • The structure type may only reside in IN/INOUT memory blocks.
  • If the last member of the structure is an array, the array's size is calculated based upon max-size - (size of struct's other members).
  • If the last member of the structure is an array, the array's element type may not contain a sized structure or a conformant array (see scl_conform).
max-size Integer Specifies the number of bytes to be allocated for the sized struct.

The following restrictions apply:

  • The max-size type must be an integral type (int, short, char).
  • The max-size value (at runtime) may not be less than the structure's type size.
  • The max-size value (at runtime) may not exceed the maximum payload size.
  • The max_size field must be in the same payload block as the type-name sized struct (i.e. no indirection '*' or '->').

Examples

Example 1

This example shows the declaration for a simple sized struct.

typedef struct {
    int nSize;
    int nSomeJunk;
    int nMoreJunk;
} SimpleSizedStruct;

extern void f(SimpleSizedStruct* s);
#pragma scl_function(f)
#pragma scl_struct_sized(f.s, nSize);

Example 2

This example shows the declaration of a sized struct with a conformant array.

#define SOME_BOUND 1
typedef struct {
    int nSize;
    int nSomeJunk;
    int ary[SOME_BOUND];
} ConformantArraySizedStruct;

extern void f(SimpleSizedStruct* s);
#pragma scl_function(f)
#pragma scl_struct_sized(f.s, nSize);

See Also

  • For additional information on scl_string, including constraints, refer to the section on scl_struct_sized in the SCL Reference Guide.