1 files changed, 310 insertions, 0 deletions
diff --git a/src/global/tok822_tree.c b/src/global/tok822_tree.c
new file mode 100644
index 0000000..a66cf11
--- /dev/null
+++ b/src/global/tok822_tree.c
@@ -0,0 +1,310 @@
+/*++
+/* NAME
+/*	tok822_tree 3
+/* SUMMARY
+/*	assorted token tree operators
+/* SYNOPSIS
+/*	#include <tok822.h>
+/*
+/*	TOK822	*tok822_append(t1, t2)
+/*	TOK822	*t1;
+/*	TOK822	*t2;
+/*
+/*	TOK822	*tok822_prepend(t1, t2)
+/*	TOK822	*t1;
+/*	TOK822	*t2;
+/*
+/*	TOK822	*tok822_cut_before(tp)
+/*	TOK822	*tp;
+/*
+/*	TOK822	*tok822_cut_after(tp)
+/*	TOK822	*tp;
+/*
+/*	TOK822	*tok822_unlink(tp)
+/*	TOK822	*tp;
+/*
+/*	TOK822	*tok822_sub_append(t1, t2)
+/*	TOK822	*t1;
+/*
+/*	TOK822	*tok822_sub_prepend(t1, t2)
+/*	TOK822	*t1;
+/*	TOK822	*t2;
+/*
+/*	TOK822	*tok822_sub_keep_before(t1, t2)
+/*	TOK822	*tp;
+/*
+/*	TOK822	*tok822_sub_keep_after(t1, t2)
+/*	TOK822	*tp;
+/*
+/*	int	tok822_apply(list, type, action)
+/*	TOK822	*list;
+/*	int	type;
+/*	int	(*action)(TOK822 *token);
+/*
+/*	int	tok822_grep(list, type)
+/*	TOK822	*list;
+/*	int	type;
+/*
+/*	TOK822	*tok822_free_tree(tp)
+/*	TOK822	*tp;
+/* DESCRIPTION
+/*	This module manipulates trees of token structures. Trees grow
+/*	to the right or downwards. Operators are provided to cut and
+/*	combine trees in various manners.
+/*
+/*	tok822_append() appends the token list \fIt2\fR to the right
+/*	of token list \fIt1\fR. The result is the last token in \fIt2\fR.
+/*	The appended list inherits the \fIowner\fR attribute from \fIt1\fR.
+/*	The parent node, if any, is not updated.
+/*
+/*	tok822_prepend() inserts the token list \fIt2\fR to the left
+/*	of token \fIt1\fR. The result is the last token in \fIt2\fR.
+/*	The appended list inherits the \fIowner\fR attribute from \fIt1\fR.
+/*	The parent node, if any, is not updated.
+/*
+/*	tok822_cut_before() breaks a token list on the left side of \fItp\fR
+/*	and returns the left neighbor of \tItp\fR.
+/*
+/*	tok822_cut_after() breaks a token list on the right side of \fItp\fR
+/*	and returns the right neighbor of \tItp\fR.
+/*
+/*	tok822_unlink() disconnects a token from its left and right neighbors
+/*	and returns the left neighbor of \tItp\fR.
+/*
+/*	tok822_sub_append() appends the token list \fIt2\fR to the right
+/*	of the token list below \fIt1\fR. The result is the last token
+/*	in \fIt2\fR.
+/*
+/*	tok822_sub_prepend() prepends the token list \fIt2\fR to the left
+/*	of the token list below \fIt1\fR. The result is the last token
+/*	in \fIt2\fR.
+/*
+/*	tok822_sub_keep_before() keeps the token list below \fIt1\fR on the
+/*	left side of \fIt2\fR and returns the tail of the disconnected list.
+/*
+/*	tok822_sub_keep_after() keeps the token list below \fIt1\fR on the
+/*	right side of \fIt2\fR and returns the head of the disconnected list.
+/*
+/*	tok822_apply() applies the specified action routine to all tokens
+/*	matching the given type (to all tokens when a null type is given).
+/*	Processing terminates when the action routine returns a non-zero
+/*	value. The result is the last result returned by the action routine.
+/*	tok822_apply() does not traverse vertical links.
+/*
+/*	tok822_grep() returns a null-terminated array of pointers to tokens
+/*	matching the specified type (all tokens when a null type is given).
+/*	tok822_grep() does not traverse vertical links. The result must be
+/*	given to myfree().
+/*
+/*	tok822_free_tree() destroys a tree of token structures and
+/*	conveniently returns a null pointer.
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+
+/* Utility library. */
+
+#include <mymalloc.h>
+#include <vstring.h>
+
+/* Global library. */
+
+#include "tok822.h"
+
+/* tok822_append - insert token list, return end of inserted list */
+
+TOK822 *tok822_append(TOK822 *t1, TOK822 *t2)
+{
+    TOK822 *next = t1->next;
+
+    t1->next = t2;
+    t2->prev = t1;
+
+    t2->owner = t1->owner;
+    while (t2->next)
+	(t2 = t2->next)->owner = t1->owner;
+
+    t2->next = next;
+    if (next)
+	next->prev = t2;
+    return (t2);
+}
+
+/* tok822_prepend - insert token list, return end of inserted list */
+
+TOK822 *tok822_prepend(TOK822 *t1, TOK822 *t2)
+{
+    TOK822 *prev = t1->prev;
+
+    if (prev)
+	prev->next = t2;
+    t2->prev = prev;
+
+    t2->owner = t1->owner;
+    while (t2->next)
+	(t2 = t2->next)->owner = t1->owner;
+
+    t2->next = t1;
+    t1->prev = t2;
+    return (t2);
+}
+
+/* tok822_cut_before - split list before token, return predecessor token */
+
+TOK822 *tok822_cut_before(TOK822 *tp)
+{
+    TOK822 *prev = tp->prev;
+
+    if (prev) {
+	prev->next = 0;
+	tp->prev = 0;
+    }
+    return (prev);
+}
+
+/* tok822_cut_after - split list after token, return successor token */
+
+TOK822 *tok822_cut_after(TOK822 *tp)
+{
+    TOK822 *next = tp->next;
+
+    if (next) {
+	next->prev = 0;
+	tp->next = 0;
+    }
+    return (next);
+}
+
+/* tok822_unlink - take token away from list, return predecessor token */
+
+TOK822 *tok822_unlink(TOK822 *tp)
+{
+    TOK822 *prev = tp->prev;
+    TOK822 *next = tp->next;
+
+    if (prev)
+	prev->next = next;
+    if (next)
+	next->prev = prev;
+    tp->prev = tp->next = 0;
+    return (prev);
+}
+
+/* tok822_sub_append - append sublist, return end of appended list */
+
+TOK822 *tok822_sub_append(TOK822 *t1, TOK822 *t2)
+{
+    if (t1->head) {
+	return (t1->tail = tok822_append(t1->tail, t2));
+    } else {
+	t1->head = t2;
+	t2->owner = t1;
+	while (t2->next)
+	    (t2 = t2->next)->owner = t1;
+	return (t1->tail = t2);
+    }
+}
+
+/* tok822_sub_prepend - prepend sublist, return end of prepended list */
+
+TOK822 *tok822_sub_prepend(TOK822 *t1, TOK822 *t2)
+{
+    TOK822 *tp;
+
+    if (t1->head) {
+	tp = tok822_prepend(t1->head, t2);
+	t1->head = t2;
+	return (tp);
+    } else {
+	t1->head = t2;
+	t2->owner = t1;
+	while (t2->next)
+	    (t2 = t2->next)->owner = t1;
+	return (t1->tail = t2);
+    }
+}
+
+/* tok822_sub_keep_before - cut sublist, return tail of disconnected list */
+
+TOK822 *tok822_sub_keep_before(TOK822 *t1, TOK822 *t2)
+{
+    TOK822 *tail = t1->tail;
+
+    if ((t1->tail = tok822_cut_before(t2)) == 0)
+	t1->head = 0;
+    return (tail);
+}
+
+/* tok822_sub_keep_after - cut sublist, return head of disconnected list */
+
+TOK822 *tok822_sub_keep_after(TOK822 *t1, TOK822 *t2)
+{
+    TOK822 *head = t1->head;
+
+    if ((t1->head = tok822_cut_after(t2)) == 0)
+	t1->tail = 0;
+    return (head);
+}
+
+/* tok822_free_tree - destroy token tree */
+
+TOK822 *tok822_free_tree(TOK822 *tp)
+{
+    TOK822 *next;
+
+    for (/* void */; tp != 0; tp = next) {
+	if (tp->head)
+	    tok822_free_tree(tp->head);
+	next = tp->next;
+	tok822_free(tp);
+    }
+    return (0);
+}
+
+/* tok822_apply - apply action to specified tokens */
+
+int     tok822_apply(TOK822 *tree, int type, TOK822_ACTION action)
+{
+    TOK822 *tp;
+    int     result = 0;
+
+    for (tp = tree; tp; tp = tp->next) {
+	if (type == 0 || tp->type == type)
+	    if ((result = action(tp)) != 0)
+		break;
+    }
+    return (result);
+}
+
+/* tok822_grep - list matching tokens */
+
+TOK822 **tok822_grep(TOK822 *tree, int type)
+{
+    TOK822 **list;
+    TOK822 *tp;
+    int     count;
+
+    for (count = 0, tp = tree; tp; tp = tp->next)
+	if (type == 0 || tp->type == type)
+	    count++;
+
+    list = (TOK822 **) mymalloc(sizeof(*list) * (count + 1));
+
+    for (count = 0, tp = tree; tp; tp = tp->next)
+	if (type == 0 || tp->type == type)
+	    list[count++] = tp;
+
+    list[count] = 0;
+    return (list);
+}