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#include "rc.h"
// -----------------------------------------------------------------------
// globals
static Tree *nodes;
// -----------------------------------------------------------------------
// exported funcs
Tree*
newtree(void)
{
Tree *t;
alloc(t);
t->str = nil;
t->child[0] = t->child[1] = t->child[2] = nil;
t->redir.fd[0] = t->redir.fd[1] = t->redir.type = 0;
t->link = nodes, nodes = t;
return t;
}
void
freetree(Tree *t)
{
if (!t)
return;
freetree(t->child[0]);
freetree(t->child[1]);
freetree(t->child[2]);
if (t->str)
efree(t->str);
efree(t);
}
void
freenodes(void)
{
Tree *t, *u;
for (t = nodes;t;t = u) {
u = t->link;
if (t->str)
efree(t->str);
efree(t);
}
nodes = nil;
}
/* tree creation */
Tree*
tree3(int type, Tree *c0, Tree *c1, Tree *c2)
{
Tree *t;
t = newtree();
t->type = type;
t->child[0] = c0;
t->child[1] = c1;
t->child[2] = c2;
return t;
}
Tree*
tree2(int type, Tree *c0, Tree *c1)
{
return tree3(type, c0, c1, nil);
}
Tree*
tree1(int type, Tree *c0)
{
return tree3(type, c0, nil, nil);
}
/* tree hang */
Tree*
hang1(Tree *p, Tree *c0)
{
p->child[0] = c0;
return p;
}
Tree*
hang2(Tree *p, Tree *c0, Tree *c1)
{
p->child[0] = c0;
p->child[1] = c1;
return p;
}
Tree*
hang3(Tree *p, Tree *c0, Tree *c1, Tree *c2)
{
p->child[0] = c0;
p->child[1] = c1;
p->child[2] = c2;
return p;
}
/* hangs the cmd underneath the epilogue */
Tree*
epihang(Tree *c, Tree *epi)
{
Tree *p;
if(!epi)
return c;
for(p=epi;p->child[1];p = p->child[1])
;
p->child[1] = c;
return epi;
}
/* hangs tree t from a new simple node. percolates redirections to root */
Tree*
simplehang(Tree *t)
{
Tree *u;
t = tree1(Tsimple, t);
for(u = t->child[0];u->type==Targs;u=u->child[0]) {
if (u->child[1]->type==Tdup
|| u->child[1]->type==Tredir){
u->child[1]->child[1] = t;
t = u->child[1];
u->child[1] = nil;
}
}
return t;
}
Tree*
wordnode(char *w)
{
Tree *t = newtree();
t->type = Tword;
t->str = strdup(w);
return t;
}
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