Guido van Rossum | 85a5fbb | 1990-10-14 12:07:46 +0000 | [diff] [blame] | 1 | /* Parse tree node implementation */ |
| 2 | |
| 3 | #include "PROTO.h" |
| 4 | #include "malloc.h" |
| 5 | #include "node.h" |
| 6 | |
| 7 | node * |
| 8 | newnode(type) |
| 9 | int type; |
| 10 | { |
| 11 | node *n = NEW(node, 1); |
| 12 | if (n == NULL) |
| 13 | return NULL; |
| 14 | n->n_type = type; |
| 15 | n->n_str = NULL; |
| 16 | n->n_nchildren = 0; |
| 17 | n->n_child = NULL; |
| 18 | return n; |
| 19 | } |
| 20 | |
| 21 | #define XXX 3 /* Node alignment factor to speed up realloc */ |
| 22 | #define XXXROUNDUP(n) ((n) == 1 ? 1 : ((n) + XXX - 1) / XXX * XXX) |
| 23 | |
| 24 | node * |
| 25 | addchild(n1, type, str) |
| 26 | register node *n1; |
| 27 | int type; |
| 28 | char *str; |
| 29 | { |
| 30 | register int nch = n1->n_nchildren; |
| 31 | register int nch1 = nch+1; |
| 32 | register node *n; |
| 33 | if (XXXROUNDUP(nch) < nch1) { |
| 34 | n = n1->n_child; |
| 35 | nch1 = XXXROUNDUP(nch1); |
| 36 | RESIZE(n, node, nch1); |
| 37 | if (n == NULL) |
| 38 | return NULL; |
| 39 | n1->n_child = n; |
| 40 | } |
| 41 | n = &n1->n_child[n1->n_nchildren++]; |
| 42 | n->n_type = type; |
| 43 | n->n_str = str; |
| 44 | n->n_nchildren = 0; |
| 45 | n->n_child = NULL; |
| 46 | return n; |
| 47 | } |
Guido van Rossum | 03a24cd | 1990-11-18 17:37:06 +0000 | [diff] [blame^] | 48 | |
| 49 | static void |
| 50 | freechildren(n) |
| 51 | node *n; |
| 52 | { |
| 53 | int i; |
| 54 | for (i = NCH(n); --i >= 0; ) |
| 55 | freechildren(CHILD(n, i)); |
| 56 | if (n->n_child != NULL) |
| 57 | DEL(n->n_child); |
| 58 | if (STR(n) != NULL) |
| 59 | DEL(STR(n)); |
| 60 | } |
| 61 | |
| 62 | void |
| 63 | freenode(n) |
| 64 | node *n; |
| 65 | { |
| 66 | if (n != NULL) { |
| 67 | freechildren(n); |
| 68 | DEL(n); |
| 69 | } |
| 70 | } |