scl/src/exec.c
Jacob 6e05f1334a Updated grammar rules for new scope system.
Need to implement scope fields still though.
2025-04-12 14:29:39 -04:00

145 lines
3.6 KiB
C

#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include "include/ast.h"
#include "include/builtin.h"
#include "include/exec.h"
#include "include/htab.h"
#include "include/stack.h"
#include "include/util.h"
extern AST* root;
AST* exec_find(char* name);
AST* exec_start(AST* ast) {
log_dbg("Started execution.");
scope = stack_init();
HTab* global = htab_init();
for (int i = 0; i < BUILTIN_FNS_LN; i++)
htab_ins(
global, BUILTIN_FNS[i].name,
ast_init(AST_TYPE_BIF, ast_bif_data_init(BUILTIN_FNS[i].fn))
);
// Push global namespace to `scope`.
stack_push(scope, global);
return exec_exp(ast);
}
AST* exec_exp(AST* ast) {
switch (ast->type) {
case AST_TYPE_BLOCK: return exec_block(ast);
case AST_TYPE_CALL: return exec_call(ast);
case AST_TYPE_NUM: return ast;
case AST_TYPE_VREF: return exec_vref(ast);
case AST_TYPE_VDEF: return exec_vdef(ast);
case AST_TYPE_FDEF: return exec_fdef(ast);
default: printf("what\n"); exit(1);
}
}
AST* exec_block(AST* ast) {
ASTBlockData* block = (ASTBlockData*)ast->data;
HTab* local = htab_init();
stack_push(scope, local);
// Loop through all but last ast.
for (int i = 0; i < block->ln - 1; i++) exec_exp(block->inside[i]);
AST* last = exec_exp(block->inside[block->ln - 1]);
stack_pop(scope);
htab_destroy(local);
return last;
}
AST* exec_call(AST* ast) {
log_dbg("Started call execution.");
ASTCallData* data = (ASTCallData*)ast->data;
size_t argc = data->argc;
AST** argv = data->argv;
char* fname = data->to;
AST* fdef = exec_find(fname);
if (fdef == NULL)
return ast_init(
AST_TYPE_EXC, ast_exc_data_init("No such function found.", NULL)
);
switch (fdef->type) {
case AST_TYPE_BIF:
ASTBIFData bifdata = fdef->data;
return bifdata(argc, argv);
case AST_TYPE_FDEF: return exec_cf(fdef, argc, argv);
default:
return ast_init(AST_TYPE_EXC, ast_exc_data_init("Good job!", NULL));
}
}
AST* exec_cf(AST* ast, size_t argc, AST** argv) {
ASTFDefData* fdef = (ASTFDefData*)ast->data;
for (int i = 0; i < argc; i++) {
char* key = ((ASTArgData*)fdef->argv[i]->data)->name;
AST* val = argv[i];
htab_ins(scope->buf[scope->ln - 1], key, val);
}
return exec_exp(fdef->body);
}
AST* exec_find(char* name) {
AST* val = NULL;
for (int i = scope->ln - 1; i >= 0; i--) {
HTab* lvl = scope->buf[i];
val = htab_get(lvl, name);
if (val != NULL) return val;
}
return NULL;
}
AST* exec_vdef(AST* ast) {
ASTVDefData* data = (ASTVDefData*)ast->data;
AST* val = data->val;
char* key = data->name;
htab_ins(scope->buf[scope->ln - 1], key, val);
return exec_exp(val);
}
AST* exec_vref(AST* ast) {
log_dbg("attempting to reference var");
ASTVrefData* vref = (ASTVrefData*)ast->data;
AST* found = exec_find(vref->to);
if (found == NULL) {
// TODO: Better memory management here.
static char msg[256];
snprintf(
msg, sizeof(msg), "Could not find value in scope for `%s`.",
vref->to
);
return ast_init(AST_TYPE_EXC, ast_exc_data_init(msg, NULL));
}
return exec_exp(found);
}
AST* exec_fdef(AST* ast) {
ASTFDefData* fdef = (ASTFDefData*)ast->data;
AST* val = fdef->body;
char* key = fdef->name;
htab_ins(scope->buf[scope->ln - 1], key, val);
return val; // Function definitions return function body.
}
void exec_print(double n) { printf("= %lf\n", n); }