Add David Gilbert's variadic function call support

man/Makefile.am

@@ -2,7 +2,7 @@
 
 AUTOMAKE_OPTIONS=foreign
 
-EXTRA_DIST = ffi.3 ffi_call.3 ffi_prep_cif.3
+EXTRA_DIST = ffi.3 ffi_call.3 ffi_prep_cif.3 ffi_prep_cif_var.3
 
-man_MANS = ffi.3 ffi_call.3 ffi_prep_cif.3
+man_MANS = ffi.3 ffi_call.3 ffi_prep_cif.3 ffi_prep_cif_var.3
 

man/ffi.3

@@ -16,6 +16,15 @@ libffi, -lffi
 .Fa "ffi_type **atypes"
 .Fc
 .Ft void
+.Fo ffi_prep_cif_var
+.Fa "ffi_cif *cif"
+.Fa "ffi_abi abi"
+.Fa "unsigned int nfixedargs"
+.Fa "unsigned int ntotalargs"
+.Fa "ffi_type *rtype"
+.Fa "ffi_type **atypes"
+.Fc
+.Ft void
 .Fo ffi_call
 .Fa "ffi_cif *cif"
 .Fa "void (*fn)(void)"
@@ -28,4 +37,5 @@ generate a call to another function at runtime without requiring knowledge of
 the called function's interface at compile time.
 .Sh SEE ALSO
 .Xr ffi_prep_cif 3 ,
+.Xr ffi_prep_cif_var 3 ,
 .Xr ffi_call 3

man/ffi_prep_cif.3

@@ -37,7 +37,9 @@ structs that describe the data type, size and alignment of each argument.
 points to an
 .Nm ffi_type
 that describes the data type, size and alignment of the
-return value.
+return value. Note that to call a variadic function
+.Nm ffi_prep_cif_var
+must be used instead.
 .Sh RETURN VALUES
 Upon successful completion,
 .Nm ffi_prep_cif
@@ -63,4 +65,6 @@ defined in
 .
 .Sh SEE ALSO
 .Xr ffi 3 ,
-.Xr ffi_call 3 
+.Xr ffi_call 3 ,
+.Xr ffi_prep_cif_var 3
+

man/ffi_prep_cif_var.3

@@ -0,0 +1,73 @@
+.Dd January 25, 2011
+.Dt ffi_prep_cif_var 3
+.Sh NAME
+.Nm ffi_prep_cif_var
+.Nd Prepare a
+.Nm ffi_cif
+structure for use with
+.Nm ffi_call
+for variadic functions.
+.Sh SYNOPSIS
+.In ffi.h
+.Ft ffi_status
+.Fo ffi_prep_cif_var
+.Fa "ffi_cif *cif"
+.Fa "ffi_abi abi"
+.Fa "unsigned int nfixedargs"
+.Fa "unsigned int ntotalargs"
+.Fa "ffi_type *rtype"
+.Fa "ffi_type **atypes"
+.Fc
+.Sh DESCRIPTION
+The
+.Nm ffi_prep_cif_var
+function prepares a
+.Nm ffi_cif
+structure for use with
+.Nm ffi_call
+for variadic functions.
+.Fa abi
+specifies a set of calling conventions to use.
+.Fa atypes
+is an array of
+.Fa ntotalargs
+pointers to
+.Nm ffi_type
+structs that describe the data type, size and alignment of each argument.
+.Fa rtype
+points to an
+.Nm ffi_type
+that describes the data type, size and alignment of the
+return value.
+.Fa nfixedargs
+must contain the number of fixed (non-variadic) arguments.
+Note that to call a non-variadic function
+.Nm ffi_prep_cif
+must be used.
+.Sh RETURN VALUES
+Upon successful completion,
+.Nm ffi_prep_cif_var
+returns
+.Nm FFI_OK .
+It will return
+.Nm FFI_BAD_TYPEDEF
+if
+.Fa cif
+is
+.Nm NULL
+or
+.Fa atypes
+or
+.Fa rtype
+is malformed. If
+.Fa abi
+does not refer to a valid ABI,
+.Nm FFI_BAD_ABI
+will be returned. Available ABIs are
+defined in
+.Nm <ffitarget.h>
+.
+.Sh SEE ALSO
+.Xr ffi 3 ,
+.Xr ffi_call 3 ,
+.Xr ffi_prep_cif 3