release: rc-1.4

1 files changed, 172 insertions, 0 deletions

diff --git a/tree.c b/tree.c
new file mode 100644
index 0000000..6ce1ee8
--- /dev/null
+++ b/tree.c
@@ -0,0 +1,172 @@
+/* tree.c: functions for manipulating parse-trees. (create, copy, delete) */
+
+#include "rc.h"
+
+/* make a new node, pass it back to yyparse. Used to generate the parsetree. */
+
+extern Node *mk(int /*nodetype*/ t,...) {
+	va_list ap;
+	Node *n;
+	va_start(ap, t);
+	switch (t) {
+	default:
+		panic("unexpected node in mk");
+		/* NOTREACHED */
+	case nDup:
+		n = nalloc(offsetof(Node, u[3]));
+		n->u[0].i = va_arg(ap, int);
+		n->u[1].i = va_arg(ap, int);
+		n->u[2].i = va_arg(ap, int);
+		break;
+	case nWord: case nQword:
+		n = nalloc(offsetof(Node, u[2]));
+		n->u[0].s = va_arg(ap, char *);
+		n->u[1].s = va_arg(ap, char *);
+		break;
+	case nBang: case nNowait:
+	case nCount: case nFlat: case nRmfn: case nSubshell:
+	case nVar: case nCase:
+		n = nalloc(offsetof(Node, u[1]));
+		n->u[0].p = va_arg(ap, Node *);
+		break;
+	case nAndalso: case nAssign: case nBackq: case nBody: case nBrace: case nConcat:
+	case nElse: case nEpilog: case nIf: case nNewfn: case nCbody:
+	case nOrelse: case nPre: case nArgs: case nSwitch:
+	case nMatch: case nVarsub: case nWhile: case nLappend:
+		n = nalloc(offsetof(Node, u[2]));
+		n->u[0].p = va_arg(ap, Node *);
+		n->u[1].p = va_arg(ap, Node *);
+		break;
+	case nForin:
+		n = nalloc(offsetof(Node, u[3]));
+		n->u[0].p = va_arg(ap, Node *);
+		n->u[1].p = va_arg(ap, Node *);
+		n->u[2].p = va_arg(ap, Node *);
+		break;
+	case nPipe:
+		n = nalloc(offsetof(Node, u[4]));
+		n->u[0].i = va_arg(ap, int);
+		n->u[1].i = va_arg(ap, int);
+		n->u[2].p = va_arg(ap, Node *);
+		n->u[3].p = va_arg(ap, Node *);
+		break;
+	case nRedir:
+	case nNmpipe:
+		n = nalloc(offsetof(Node, u[3]));
+		n->u[0].i = va_arg(ap, int);
+		n->u[1].i = va_arg(ap, int);
+		n->u[2].p = va_arg(ap, Node *);
+		break;
+ 	}
+	n->type = t;
+	va_end(ap);
+	return n;
+}
+
+/* copy a tree to malloc space. Used when storing the definition of a function */
+
+extern Node *treecpy(Node *s, void *(*alloc)(SIZE_T)) {
+	Node *n;
+	if (s == NULL)
+		return NULL;
+	switch (s->type) {
+	default:
+		panic("unexpected node in treecpy");
+		/* NOTREACHED */
+	case nDup:
+		n = (*alloc)(offsetof(Node, u[3]));
+		n->u[0].i = s->u[0].i;
+		n->u[1].i = s->u[1].i;
+		n->u[2].i = s->u[2].i;
+		break;
+	case nWord: case nQword:
+		n = (*alloc)(offsetof(Node, u[2]));
+		n->u[0].s = strcpy((char *) (*alloc)(strlen(s->u[0].s) + 1), s->u[0].s);
+		if (s->u[1].s != NULL) {
+			SIZE_T i = strlen(s->u[0].s);
+			n->u[1].s = (*alloc)(i);
+			memcpy(n->u[1].s, s->u[1].s, i);
+		} else
+			n->u[1].s = NULL;
+		break;
+	case nBang: case nNowait: case nCase:
+	case nCount: case nFlat: case nRmfn: case nSubshell: case nVar:
+		n = (*alloc)(offsetof(Node, u[1]));
+		n->u[0].p = treecpy(s->u[0].p, alloc);
+		break;
+	case nAndalso: case nAssign: case nBackq: case nBody: case nBrace: case nConcat:
+	case nElse: case nEpilog: case nIf: case nNewfn: case nCbody:
+	case nOrelse: case nPre: case nArgs: case nSwitch:
+	case nMatch: case nVarsub: case nWhile: case nLappend:
+		n = (*alloc)(offsetof(Node, u[2]));
+		n->u[0].p = treecpy(s->u[0].p, alloc);
+		n->u[1].p = treecpy(s->u[1].p, alloc);
+		break;
+	case nForin:
+		n = (*alloc)(offsetof(Node, u[3]));
+		n->u[0].p = treecpy(s->u[0].p, alloc);
+		n->u[1].p = treecpy(s->u[1].p, alloc);
+		n->u[2].p = treecpy(s->u[2].p, alloc);
+		break;
+	case nPipe:
+		n = (*alloc)(offsetof(Node, u[4]));
+		n->u[0].i = s->u[0].i;
+		n->u[1].i = s->u[1].i;
+		n->u[2].p = treecpy(s->u[2].p, alloc);
+		n->u[3].p = treecpy(s->u[3].p, alloc);
+		break;
+	case nRedir:
+	case nNmpipe:
+		n = (*alloc)(offsetof(Node, u[3]));
+		n->u[0].i = s->u[0].i;
+		n->u[1].i = s->u[1].i;
+		n->u[2].p = treecpy(s->u[2].p, alloc);
+		break;
+	}
+	n->type = s->type;
+	return n;
+}
+
+/* free a function definition that is no longer needed */
+
+extern void treefree(Node *s) {
+	if (s == NULL)
+		return;
+	switch (s->type) {
+	default:
+		panic("unexpected node in treefree");
+		/* NOTREACHED */
+	case nDup:
+		break;
+	case nWord: case nQword:
+		efree(s->u[0].s);
+		efree(s->u[1].s);
+		break;
+	case nBang: case nNowait:
+	case nCount: case nFlat: case nRmfn:
+	case nSubshell: case nVar: case nCase:
+		treefree(s->u[0].p);
+		break;
+	case nAndalso: case nAssign: case nBackq: case nBody: case nBrace: case nConcat:
+	case nElse: case nEpilog: case nIf: case nNewfn:
+	case nOrelse: case nPre: case nArgs: case nCbody:
+	case nSwitch: case nMatch:  case nVarsub: case nWhile:
+	case nLappend:
+		treefree(s->u[1].p);
+		treefree(s->u[0].p);
+		break;
+	case nForin:
+		treefree(s->u[2].p);
+		treefree(s->u[1].p);
+		treefree(s->u[0].p);
+		break;
+	case nPipe:
+		treefree(s->u[2].p);
+		treefree(s->u[3].p);
+		break;
+	case nRedir:
+	case nNmpipe:
+		treefree(s->u[2].p);
+	}
+	efree(s);
+}