post-scarcity/src/c/environment/function_bindings.c
2026-05-07 06:47:58 +01:00

354 lines
13 KiB
C

/**
* environment/function_bindings.c
*
* Post Scarcity Software Environment:
*
* Provide bindings for substrate functions. At least in theory, these
* bindings only need to be initialised on node zero.
* todo: they really ought to be in a namespace ::system:bootstrap, once I
* have namespaces and paths working.
*
* (c) 2026 Simon Brooke <simon@journeyman.cc>
* Licensed under GPL version 2.0, or, at your option, any later version.
*/
#include <stdbool.h>
#include <stdlib.h>
#include <wchar.h>
#include "debug.h"
#include "environment/privileged_keywords.h"
#include "io/io.h"
#include "io/peek.h"
#include "io/print.h"
#include "io/read.h"
#include "memory/node.h"
#include "memory/pointer.h"
#include "memory/tags.h"
#include "ops/assoc.h"
#include "ops/bind.h"
#include "ops/cond.h"
#include "ops/eq.h"
#include "ops/eval_apply.h"
#include "ops/inspect.h"
#include "ops/keys.h"
#include "ops/list_ops.h"
#include "ops/mapcar.h"
#include "ops/progn.h"
#include "ops/quote.h"
#include "ops/repl.h"
#include "ops/reverse.h"
#include "payloads/stack.h"
#include "ops/string_ops.h"
#include "ops/truth.h"
#include "payloads/cons.h"
#include "payloads/function.h"
#include "payloads/special.h"
#include "payloads/stack.h"
/**
* Bind this compiled `executable` function, as a Lisp function, to
* this name in the `oblist`.
* \todo where a function is not compiled from source, we could cache
* the name on the source pointer. Would make stack frames potentially
* more readable and aid debugging generally.
*/
struct pso_pointer
bind_function( struct pso_pointer frame_pointer, wchar_t *name, wchar_t *doc,
struct pso_pointer ( *executable ) ( struct pso_pointer ) ) {
struct pso_pointer result = fetch_env( frame_pointer );
struct pso_pointer n = c_string_to_lisp_symbol( frame_pointer, name );
struct pso_pointer d = c_string_to_lisp_string( frame_pointer, doc );
struct pso_pointer meta = make_cons( frame_pointer,
make_cons( frame_pointer,
privileged_keyword_layer,
privileged_keyword_bootstrap ),
make_cons( frame_pointer,
make_cons( frame_pointer,
privileged_keyword_name,
n ),
make_cons( frame_pointer,
make_cons
( frame_pointer,
privileged_keyword_documentation,
d ),
nil ) ) );
struct pso_pointer r = make_function( frame_pointer, meta, executable );
debug_print( doc, DEBUG_BOOTSTRAP, 0 );
if ( !exceptionp( r ) ) {
debug_print( L"... bound\n", DEBUG_BOOTSTRAP, 0 );
result =
make_cons( frame_pointer, make_cons( frame_pointer, n, r ),
result );
} else {
debug_print( L"... failed to bind\n", DEBUG_BOOTSTRAP, 0 );
}
return result;
}
/**
* Bind this compiled `executable` function, as a Lisp special form, to
* this `name` in the `oblist`.
*/
struct pso_pointer
bind_special( struct pso_pointer frame_pointer, wchar_t *name, wchar_t *doc,
struct pso_pointer ( *executable ) ( struct pso_pointer ) ) {
struct pso_pointer result = fetch_env( frame_pointer );
struct pso_pointer n = c_string_to_lisp_symbol( frame_pointer, name );
struct pso_pointer d = c_string_to_lisp_string( frame_pointer, doc );
struct pso_pointer meta = make_cons( frame_pointer,
make_cons( frame_pointer,
privileged_keyword_bootstrap,
nil ),
make_cons( frame_pointer,
make_cons( frame_pointer,
privileged_keyword_name,
n ),
make_cons( frame_pointer,
make_cons
( frame_pointer,
privileged_keyword_documentation,
d ),
nil ) ) );
struct pso_pointer r = make_special( frame_pointer, meta, executable );
debug_print( doc, DEBUG_BOOTSTRAP, 0 );
if ( !exceptionp( r ) ) {
debug_print( L"... bound\n", DEBUG_BOOTSTRAP, 0 );
result =
make_cons( frame_pointer, make_cons( frame_pointer, n, r ),
result );
} else {
debug_print( L"... failed to bind\n", DEBUG_BOOTSTRAP, 0 );
}
return result;
}
struct function_data {
wchar_t *name;
wchar_t *documentation;
void *executable;
};
/* right, the problem with all those pretty '#ifdefs' which might allow us to
* simply switch functions on and off just by including or not including .h
* files is that the C compiler is too primitive to know how many items there
* are in an array. So this number must be edited manually, and must be right.
*/
#define N_FUNCTION_INITIALISERS 4
/** initialisers for functions */
struct function_data function_initialisers[] = {
#ifdef _psse_io_io_h
{L"close", L"(close stream): close `stream`.", &lisp_close},
{L"open",
L"(open stream), (open stream write?): open `stream`; if `write?` is "
L"present and is non-nil, open for writing, else for reading.",
&lisp_open},
{L"slurp",
L"(slurp stream): read the whole contents of this `stream`, "
L"which may "
L"be an open stream open for reading or a URL, into a string, and return "
L"the " L"string.",
&lisp_slurp},
#endif
#ifdef __psse_io_peek_h
{L"peek",
L"(peek stream): return the next character which may be read from "
L"`stream`, without removing it.",
&peek},
#endif
#ifdef __psse_io_print_h
{L"print",
L"(print object), (print object stream) print this `object` in a format "
L"suitable to be read by `read`, q.v.; if `stream` is specified and is a "
L"stream open for writing, to that stream.",
&print},
{L"princ",
L"(princ object), (princ object stream) print this `object` in a format "
L"more suited to human readers; if `stream` is specified and is a stream "
L"open for writing, to that stream.",
&print},
#endif
#ifdef __psse_io_read_h
{L"read",
L"(read stream) read one complete Lisp expression from `stream`, and "
L"return that expression unevaluated.",
&read},
{L"read-character",
L"(read-character stream): read a single character from `stream` and "
L"return it.",
&read_character},
{L"read-number",
L"(read-number stream): read a number from `stream` and return it.",
&read_number},
{L"read-symbol",
L"(read-symbol stream): read a symbol from `stream` and return it.",
&read_symbol},
#endif
#ifdef __psse_ops_assoc_h
{L"assoc",
L"(assoc key store): search `store` for the value associated with "
L"`key`.",
&assoc},
#endif
#ifdef __psse_ops_bind_h
{L"bind!",
L"(bind! key value store): bind `key` to `value` in this store, modifying "
L"the store if it is writable to the user, otherwise returning a new "
L"store",
&bind},
#endif
#ifdef __psse_ops_eq_h
{L"eq",
L"(eq args...): shallow, cheap equality; returns `t` if all `args...` "
L"are the same object, else `nil`.",
&eq},
{L"equal",
L"(equal a b): expensive, deep equality: returns `t` if objects `a` "
L"and `b` have recursively equal value.",
&equal},
#endif
#ifdef __psse_ops_eval_apply_h
// TODO: there's a lot of other stuff in eval_apply.c, which ought to be in
// other files but at present isn't.
{L"apply",
L"(apply fn args...): apply this `fn` to these `args...` and return "
L"their value.",
&lisp_apply},
{L"eval",
L"(eval expression): evaluate this `expression` and return its value",
&lisp_eval},
#endif
#ifdef __psse_ops_inspect_h
{L"inspect",
L"(inspect expr), (inspect expr write-stream): inspect one complete "
L"lisp expression and return `nil`. If `write-stream` is specified and "
L"is a write stream, then print to that stream, else to the stream "
L"which is the value of `*out*` in the environment.",
&lisp_inspect},
#endif
#ifdef __psse_ops_keys_h
{L"keys", L"(keys store): returns a list of the keys in this `store`.",
&lisp_keys},
#endif
#ifdef __psse_ops_list_ops_h
{L"count",
L"(count sequence): returns the number of top level elements in "
L"`sequence`.",
&count},
#endif
#ifdef __psse_ops_mapcar_h
{L"mapcar",
L"(mapcar fn list): map this `fn` over this `list`, and return a list "
L"of the results.",
&lisp_mapcar},
#endif
#ifdef __psse_ops_progn_h
{L"progn",
L"(progn expressions...): Evaluate each expression in "
L"`expressions` in turn and return the value of the last.",
&lisp_progn},
#endif
#ifdef __psse_ops_repl_h
{L"repl", L"(repl show_prompt?): Start a new read, eval, print loop.",
&repl},
#endif
#ifdef __psse_ops_reverse_h
{L"reverse",
L"(reverse sequence): return a sequence like this `sequence`, but with "
L"the order of top level elements reversed.",
&reverse},
#endif
#ifdef __psse_ops_truth_h
{L"and",
L"(and expressions...): returns `t` if none of these `expressions...` "
L"evaluates to `nil`, else `nil`.",
&and},
{L"nil?",
L"(nil? expression): returns `t` if `expression` evaluates to `nil`, else "
L"`nil`.",
&nilp},
{L"not",
L"(not expression): returns `t` unless `expression` evaluates to `nil`, "
L"else " L"`nil`.",
&not},
{L"or",
L"(or expressions...): returns `nil` if every one of these `expressions...` "
L"evaluates to `nil`, else `t`.",
&or},
{L"true?",
L"(true? expression): returns `t` if `expression` evaluates to `t`, else "
L"`nil`.",
&truep},
#endif
{L"END MARKER", L"END MARKER", NULL}
};
/* right, the problem with all those pretty '#ifdefs' which might allow us to
* simply switch functions on and off just by including or not including .h
* files is that the C compiler is too primitive to know how many items there
* are in an array */
#define N_SPECIAL_INITIALISERS 1
/** initialisers for special forms */
struct function_data special_initialisers[] = {
#ifdef __psse_ops_cond_h
{L"cond",
L"(cond clauses...): special form; conditional. Each `clause` is expected "
L"to be a "
L"list; if the first item in such a list evaluates to non-nil, the "
L"remaining items in that list are evaluated in turn and the value of "
L"the last returned. If no arg `clause` has a first element which "
L"evaluates to non nil, then nil is returned",
&lisp_cond},
#endif
#ifdef __psse_ops_quote_h
{L"quote",
L"(quote expression): special form; protect `expression` from "
L"evaluation.",
&quote},
#endif
{L"END MARKER", L"END MARKER", NULL}
};
struct pso_pointer
initialise_function_bindings( struct pso_pointer frame_pointer ) {
struct pso_pointer result = fetch_env( frame_pointer );
for ( int i = 0; function_initialisers[i].executable != NULL; i++ ) {
struct pso_pointer b = c_car( bind_function( frame_pointer,
function_initialisers
[i].name,
function_initialisers
[i].documentation,
function_initialisers
[i].executable ) );
result = make_cons( frame_pointer, b, result );
}
for ( int i = 0; special_initialisers[i].executable != NULL; i++ ) {
struct pso_pointer b = c_car( bind_special( frame_pointer,
special_initialisers
[i].name,
special_initialisers
[i].documentation,
special_initialisers
[i].executable ) );
result = make_cons( frame_pointer, b, result );
}
return result;
}