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#include "rc.h"
#include "exec.h"
#include "io.h"
#include "fns.h"
tree *treenodes;
/*
* create and clear a new tree node, and add it
* to the node list.
*/
tree *newtree(void){
tree *t=new(tree);
t->iskw=0;
t->str=0;
t->child[0]=t->child[1]=t->child[2]=0;
t->next=treenodes;
treenodes=t;
return t;
}
void freenodes(void){
tree *t, *u;
for(t=treenodes;t;t=u){
u=t->next;
if(t->str) efree(t->str);
efree((char *)t);
}
treenodes=0;
}
tree *tree1(int type, tree *c0)
{
return tree3(type, c0, (tree *)0, (tree *)0);
}
tree *tree2(int type, tree *c0, tree *c1)
{
return tree3(type, c0, c1, (tree *)0);
}
tree *tree3(int type, tree *c0, tree *c1, tree *c2)
{
tree *t;
if(type==';'){
if(c0==0) return c1;
if(c1==0) return c0;
}
t=newtree();
t->type=type;
t->child[0]=c0;
t->child[1]=c1;
t->child[2]=c2;
return t;
}
tree *mung1(tree *t, tree *c0)
{
t->child[0]=c0;
return t;
}
tree *mung2(tree *t, tree *c0, tree *c1)
{
t->child[0]=c0;
t->child[1]=c1;
return t;
}
tree *mung3(tree *t, tree *c0, tree *c1, tree *c2)
{
t->child[0]=c0;
t->child[1]=c1;
t->child[2]=c2;
return t;
}
tree *epimung(tree *comp, tree *epi)
{
tree *p;
if(epi==0) return comp;
for(p=epi;p->child[1];p=p->child[1]);
p->child[1]=comp;
return epi;
}
/*
* Add a SIMPLE node at the root of t and percolate all the redirections
* up to the root.
*/
tree *simplemung(tree *t)
{
tree *u;
struct io *s;
t=tree1(SIMPLE, t);
s=openstr();
pfmt(s, "%t", t);
t->str=strdup(s->strp);
closeio(s);
for(u=t->child[0];u->type==ARGLIST;u=u->child[0]){
if(u->child[1]->type==DUP
|| u->child[1]->type==REDIR){
u->child[1]->child[1]=t;
t=u->child[1];
u->child[1]=0;
}
}
return t;
}
tree *token(char *str, int type)
{
tree *t=newtree();
t->type=type;
t->str=strdup(str);
return t;
}
void freetree(tree *p)
{
if(p==0) return;
freetree(p->child[0]);
freetree(p->child[1]);
freetree(p->child[2]);
if(p->str) efree(p->str);
efree((char *)p);
}
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