foreign-c/docs/reference.md

Reference

Types

Types are given as symbols, for example 'int8 or 'pointer.

• int8
• uint8
• int16
• uint16
• int32
• uint32
• int64
• uint64
• char
• unsigned-char
• short
• unsigned-short
• int
• unsigned-int
• long
• unsigned-long
• float
• double
• pointer

Procedures or macros

On some implementations these are procedures, on some macros.

The arguments are in form

• NAME - TYPE

The return value is in form

• TYPE

pffi-shared-object-auto-load

Arguments:

• headers - (list string ...)
  • C headers of the library
  • For example (list "curl/curl.h")
• object-name - symbol
  • The name of the dynamic library file you want to load
  • Without the "lib" in front of it
  • Without the ".so" or ".dll" at the end
• additional-versions - (list string...)
  • For example (list ".0" ".1")
• additional-paths - (list string...)
  • Any additional paths you want to search for the library
  • For example (list "./mylibs")

Returns:

• object - Shared object, the type depends on the implementation

pffi-shared-object-load

It is recommended to use the pffi-shared-object-auto-load instead of this directly.

Arguments:

• headers - (list string ...) - Headers that need to be included - Example (list "curl/curl.h")
• path - string - The full path to the shared object you want to load, including any "lib" infront and .so/.dll at the end - Example "libcurl.so"

Returns:

• object - Shared object, the type depends on the implementation

pffi-define

Defines new foreign procedure.

Arguments:

• scheme-name - symbol - The name of the procedure used on scheme side
• shared-object - object - The shared object - Use pffi-shared-object-auto-load or pffi-shared-object-load to get this
• c-name - symbol - The name of the C function
• return-type - symbol - The return type of the C function
• arguments-types - (list symbol ...) - The C function argument types - Need to be given in form (list 'type 'type)

pffi-define-callback

Defines new callback function.

Arguments:

• scheme-name - The name of the function used on scheme side
• return-type - symbol - The return type of the callback
• arguments-types - (list symbol ...) - The callback function argument types
• procedure - procedure
  • Procedure used as callback function
  • Argument count must match the argument-types count

pffi-size-of

Get the size of type.

Arguments:

• type - symbol - The type you want the size of

Returns:

• number - The size of the given type

pffi-pointer-allocate

Allocates a pointer of given size.

Arguments:

• size - number - The size of the pointer you want to allocate

Returns:

• object - A pointer of given size

pffi-pointer-null

Create a null pointer.

Returns:

• object - Null pointer

pffi-string->pointer

Arguments:

• string-content - string - The string you want to transform into pointer

Returns:

• object - Pointer of the given string

pffi-pointer->string

Arguments:

• pointer - object - The pointer you want to transform to string

Returns:

• string - String from the given pointer

pffi-pointer-free

Arguments:

• pointer - object - The pointer you want to free

pffi-pointer?

Arguments:

• object - object - The object you want to check wether it is a pointer or not

Returns:

• boolean - Returns true if given object is pointer, otherwise false

pffi-pointer-set!

Arguments:

• pointer - object - The pointer you want to modify
• type - symbol - The type of value that will be put into the pointer
• offset -number - The location of the value inside the pointer - For example: (+ (pffi-size-of 'int) (pffi-size-of 'pointer)) or 0
• value - object
  • The value to be placed into the object

pffi-pointer-get

Arguments:

• pointer - object
  • The pointer you want to get the value from
• type - symbol
  • The type of value you want to get
  • For example: 'int
• offset - number
  • The location of the value inside the pointer
  • For example: (+ (pffi-size-of 'int) (pffi-size-of 'pointer)) or 0

Returns:

• object
  • The value in the poiner in the given offset as given type