1 USING: alien alien.c-types compiler.tree help.markup help.syntax
3 IN: stack-checker.alien
5 HELP: alien-node-params
6 { $class-description "Base class for the parameter slot of " { $link #alien-node } " nodes. It has the following slots:"
8 { { $slot "return" } { "a " { $link c-type-name } " which indicates the type of the functions return value." } }
9 { { $slot "parameters" } { "a " { $link sequence } " of " { $link c-type-name } " giving the types of the functions parameters." } }
10 { { $slot "abi" } { "calling convention of the function the node parameters operates on." } }
15 HELP: alien-callback-params
16 { $class-description "Class that holds the parameter types and return value type of an alien callback call." }
17 { $see-also #alien-callback } ;
20 { $values { "params" alien-node-params } { "quot" quotation } }
21 { $description "Builds a quotation which coerces values on the stack to the required types for the alien call." }
24 "USING: alien.c-types prettyprint stack-checker.alien ;"
25 "T{ alien-invoke-params { parameters { void* c-string int } } } param-prep-quot ."
26 "[ [ [ [ ] dip >c-ptr ] dip \\ utf8 string>alien ] dip >fixnum ]"
30 HELP: callback-parameter-quot
31 { $values { "params" alien-node-params } { "quot" quotation } }
32 { $description "Builds a quotation which coerces values on the stack to the required types for an alien callback. This word is essentially the opposite to " { $link param-prep-quot } "." }
35 "USING: alien.c-types prettyprint stack-checker.alien ;"
36 "T{ alien-node-params { parameters { c-string } } } callback-parameter-quot ."
37 "[ { object } declare [ ] dip \ utf8 alien>string ]"
41 HELP: infer-alien-assembly
42 { $description "Infers " { $link alien-assembly } " calls." } ;
44 HELP: infer-alien-invoke
45 { $description "Appends the necessary SSA nodes for performing an " { $link alien-invoke } " call to the IR tree being constructed." } ;
47 HELP: wrap-callback-quot
48 { $values { "params" alien-node-params } { "quot" quotation } { "quot'" quotation } }
49 { $description "Wraps the given quotation in protective packaging so that it becomes suitable to be used as an alien callback. That means that the parameters are unpacked from C types to Factor types and, if the callback returns something, the top data stack item is afterwards converted to a C compatible value." }
51 "Here a callback that returns the length of a " { $link c-string } " is wrapped:"
53 "USING: alien.c-types prettyprint stack-checker.alien ;"
54 "T{ alien-node-params { return int } { parameters { c-string } } } "
55 "[ length ] wrap-callback-quot ."
58 " { object } declare [ ] dip \ utf8 alien>string"
61 " dup current-callback eq?"
62 " [ drop ] [ wait-for-callback ] if"
68 ARTICLE: "stack-checker.alien" "Inferring alien words" "This vocab contains code for inferring the words that form part of the alien FFI: " { $link alien-invoke } ", " { $link alien-indirect } ", " { $link alien-assembly } " and " { $link alien-callback } ". The words performing the inferring are:"
76 ABOUT: "stack-checker.alien"