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#include "rc.h"
#include "parse.h"
static Tree *nodes;
Tree*
maketree(void)
{
Tree *node = emalloc(sizeof(*node));
node->link = nodes;
nodes = node;
return node;
}
void
freeparsetree(void)
{
Tree *t, *nt;
for(t = nodes; t; t = nt) {
nt = t->link;
if(t->type == Tword && t->str)
efree(t->str);
efree(t);
}
nodes = nil;
}
Tree*
maketree1(int type, Tree *c0)
{
return maketree2(type, c0, nil);
}
Tree*
maketree2(int type, Tree *c0, Tree *c1)
{
return maketree3(type, c0, c1, nil);
}
Tree*
maketree3(int type, Tree *c0, Tree *c1, Tree *c2)
{
Tree *node = maketree();
node->type = type;
node->child[0] = c0;
node->child[1] = c1;
node->child[2] = c2;
return node;
}
Tree*
hangchild1(Tree *node, Tree *c, int i)
{
node->child[i] = c;
return node;
}
Tree*
hangchild2(Tree *node, Tree *c1, int i1, Tree *c2, int i2)
{
node->child[i1] = c1;
node->child[i2] = c2;
return node;
}
Tree*
hangchild3(Tree *node, Tree *c0, Tree *c1, Tree *c2)
{
node->child[0] = c0;
node->child[1] = c1;
node->child[2] = c2;
return node;
}
/*
* add a Tbasic node.
* percolate all the redirections up to the root
*/
Tree*
basictree(Tree *cmd)
{
Tree *c;
cmd = maketree1(Tbasic, cmd);
for(c=cmd->child[0]; c->type==Targs; c = c->child[0]){
if(c->child[1]->type == Tdup || c->child[1]->type == Tredir){
c->child[1]->child[1] = cmd;
cmd = c->child[1];
c->child[1] = nil;
}
}
return cmd;
}
Tree*
hangepilog(Tree *cmd, Tree *epi)
{
Tree *p;
if(!epi)
return cmd;
for(p = epi; p->child[1]; p = p->child[1])
;
p->child[1] = cmd;
return epi;
}
Tree*
token(int type, char *s)
{
Tree *node = maketree();
node->type = type;
node->str = strdup(s);
return node;
}
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