| /* Parse tree node implementation */ |
| |
| #include "pgenheaders.h" |
| #include "node.h" |
| |
| node * |
| newtree(type) |
| int type; |
| { |
| node *n = NEW(node, 1); |
| if (n == NULL) |
| return NULL; |
| n->n_type = type; |
| n->n_str = NULL; |
| n->n_lineno = 0; |
| n->n_nchildren = 0; |
| n->n_child = NULL; |
| return n; |
| } |
| |
| #define XXX 3 /* Node alignment factor to speed up realloc */ |
| #define XXXROUNDUP(n) ((n) == 1 ? 1 : ((n) + XXX - 1) / XXX * XXX) |
| |
| node * |
| addchild(n1, type, str, lineno) |
| register node *n1; |
| int type; |
| char *str; |
| int lineno; |
| { |
| register int nch = n1->n_nchildren; |
| register int nch1 = nch+1; |
| register node *n; |
| if (XXXROUNDUP(nch) < nch1) { |
| n = n1->n_child; |
| nch1 = XXXROUNDUP(nch1); |
| RESIZE(n, node, nch1); |
| if (n == NULL) |
| return NULL; |
| n1->n_child = n; |
| } |
| n = &n1->n_child[n1->n_nchildren++]; |
| n->n_type = type; |
| n->n_str = str; |
| n->n_lineno = lineno; |
| n->n_nchildren = 0; |
| n->n_child = NULL; |
| return n; |
| } |
| |
| /* Forward */ |
| static void freechildren PROTO((node *)); |
| |
| |
| void |
| freetree(n) |
| node *n; |
| { |
| if (n != NULL) { |
| freechildren(n); |
| DEL(n); |
| } |
| } |
| |
| static void |
| freechildren(n) |
| node *n; |
| { |
| int i; |
| for (i = NCH(n); --i >= 0; ) |
| freechildren(CHILD(n, i)); |
| if (n->n_child != NULL) |
| DEL(n->n_child); |
| if (STR(n) != NULL) |
| DEL(STR(n)); |
| } |