thesis-lisp/compiler/node.c

#include "node.h"

#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>

struct node *string_from_owned(char *ptr) {
    struct node *n = malloc(sizeof(struct node));
    n->type = N_STRING;
    n->n_string = ptr;
    return n;
}

struct node *cons(struct node *a, struct node *b) {
    struct node *n = malloc(sizeof(struct node));
    n->type = N_CONS;
    n->n_cons.car = a;
    n->n_cons.cdr = b;
    return n;
}

struct node *ident(const char *text) {
    struct node *n = malloc(sizeof(struct node));
    n->type = N_IDENT;
    n->n_ident = strdup(text);
    return n;
}

struct node *integer(intmax_t v) {
    struct node *n = malloc(sizeof(struct node));
    n->type = N_INTEGER;
    n->n_integer = v;
    return n;
}

struct node *list(int n, ...) {
    struct node *head, *tail, *pair;
    va_list ap;
    va_start(ap, n);
    head = NULL;
    for (int i = 0; i < n; ++i) {
        pair = cons(va_arg(ap, struct node *), NULL);
        if (head) {
            tail->n_cons.cdr = pair;
        } else {
            head = pair;
        }
        tail = pair;
    }
    va_end(ap);
    return head;
}

void vm_print(const struct node *node, int depth) {
    if (!node) {
        printf("nil");
        return;
    }
    switch (node->type) {
    case N_IDENT:
        printf("%s", node->n_ident);
        break;
    case N_INTEGER:
        printf("%zd", node->n_integer);
        break;
    case N_STRING:
        printf("\"%s\"", node->n_string);
        break;
    case N_CONS:
        if (!depth) {
            printf("(");
        }
        vm_print(node->n_cons.car, 0);
        if (node->n_cons.cdr) {
            printf(" ");
            if (node->n_cons.cdr->type == N_CONS) {
                vm_print(node->n_cons.cdr, depth + 1);
            } else {
                printf(". ");
                vm_print(node->n_cons.cdr, 0);
            }
        }
        if (!depth) {
            printf(")");
        }
        break;
    }
}