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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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