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#include "bc.h"
#include <stdio.h>
#include <stdlib.h>
static bc_expression *newexp(enum bc_expression_type t)
{
bc_expression *e = calloc(1, sizeof (*e));
if (e == NULL) {
perror("bc: out of memory:");
exit(1);
}
e->type = t;
return e;
}
void freeexp(bc_expression *exp)
{
if (exp->lval) {
bc_free(exp->lval);
}
if (exp->rval) {
bc_free(exp->rval);
}
/*
if (exp->literal) {
bc_free(exp->literal);
}
*/
if (exp->left) {
freeexp(exp->left);
}
if (exp->right) {
freeexp(exp->right);
}
free(exp);
}
bc_num *bc_eval(bc_expression *exp)
{
bc_num *r = NULL;
if (exp->left) {
exp->lval = bc_eval(exp->left);
}
if (exp->right) {
exp->rval = bc_eval(exp->right);
}
switch (exp->type) {
case NAMED:
r = bc_let(exp->letter);
break;
case LITERAL:
r = exp->literal;
break;
case FUNCTION_CALL:
r = NULL;
break;
case OPERATION:
switch (exp->op) {
case MUL: r = bc_mul(exp->lval, exp->rval); break;
case DIV: r = bc_div(exp->lval, exp->rval); break;
case ADD: r = bc_add(exp->lval, exp->rval); break;
case SUB: r = bc_sub(exp->lval, exp->rval); break;
case MOD: r = bc_mod(exp->lval, exp->rval); break;
case POW: r = bc_pow(exp->lval, exp->rval); break;
case SET: r = bc_set(exp->lval, exp->rval); break;
case SADD: r = bc_sadd(exp->lval, exp->rval); break;
case SSUB: r = bc_ssub(exp->lval, exp->rval); break;
case SMUL: r = bc_smul(exp->lval, exp->rval); break;
case SDIV: r = bc_sdiv(exp->lval, exp->rval); break;
case SMOD: r = bc_smod(exp->lval, exp->rval); break;
case SPOW: r = bc_spow(exp->lval, exp->rval); break;
case EQ: r = bc_eq(exp->lval, exp->rval); break;
case LE: r = bc_le(exp->lval, exp->rval); break;
case GE: r = bc_ge(exp->lval, exp->rval); break;
case NE: r = bc_ne(exp->lval, exp->rval); break;
case LT: r = bc_lt(exp->lval, exp->rval); break;
case GT: r = bc_gt(exp->lval, exp->rval); break;
case NEG: r = bc_neg(exp->lval); break;
case INC: r = bc_inc(exp->lval); break;
case DEC: r = bc_dec(exp->lval); break;
}
break;
}
free(exp);
return r;
}
bc_expression *bc_named(char letter)
{
bc_expression *e = newexp(NAMED);
e->letter = letter;
return e;
}
bc_expression *bc_literal(bc_num *n)
{
bc_expression *e = newexp(LITERAL);
e->literal = n;
return e;
}
bc_expression *bc_function_call(char letter, void *arg)
{
bc_expression *e = newexp(FUNCTION_CALL);
e->letter = letter;
e->literal = arg;
return e;
}
bc_expression *bc_operation(bc_op op, bc_expression *left, bc_expression *right)
{
bc_expression *e = newexp(OPERATION);
e->op = op;
e->left = left;
e->right = right;
return e;
}
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