Merge of ncurses-4.1-971129

1 files changed, 174 insertions, 0 deletions

diff --git a/lib/libcurses/tries.c b/lib/libcurses/tries.c
new file mode 100644
index 00000000000..a93e59fa983
--- /dev/null
+++ b/lib/libcurses/tries.c
@@ -0,0 +1,174 @@
+/*	$OpenBSD: tries.c,v 1.1 1997/12/03 05:21:45 millert Exp $	*/
+
+/******************************************************************************
+ * Copyright 1997 by Thomas E. Dickey <dickey@clark.net>                      *
+ * All Rights Reserved.                                                       *
+ *                                                                            *
+ * Permission to use, copy, modify, and distribute this software and its      *
+ * documentation for any purpose and without fee is hereby granted, provided  *
+ * that the above copyright notice appear in all copies and that both that    *
+ * copyright notice and this permission notice appear in supporting           *
+ * documentation, and that the name of the above listed copyright holder(s)   *
+ * not be used in advertising or publicity pertaining to distribution of the  *
+ * software without specific, written prior permission. THE ABOVE LISTED      *
+ * COPYRIGHT HOLDER(S) DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,  *
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO     *
+ * EVENT SHALL THE ABOVE LISTED COPYRIGHT HOLDER(S) BE LIABLE FOR ANY         *
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER       *
+ * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF       *
+ * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN        *
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.                   *
+ ******************************************************************************/
+
+/*
+**	tries.c
+**
+**	Functions to manage the tree of partial-completions for keycodes.
+**
+*/
+
+#include <curses.priv.h>
+
+MODULE_ID("Id: tries.c,v 1.5 1997/10/26 21:55:15 tom Exp $")
+
+#define SET_TRY(dst,src) if ((dst->ch = *src++) == 128) dst->ch = '\0'
+
+void _nc_add_to_try(struct tries **tree, char *str, unsigned short code)
+{
+	static bool     out_of_memory = FALSE;
+	struct tries    *ptr, *savedptr;
+	unsigned char	*txt = (unsigned char *)str;
+
+	if (txt == 0 || out_of_memory || code == 0)
+		return;
+
+	if ((*tree) != 0) {
+		ptr = savedptr = (*tree);
+
+		for (;;) {
+			unsigned char cmp = *txt;
+
+			while (ptr->ch != cmp
+			       &&  ptr->sibling != 0)
+				ptr = ptr->sibling;
+	
+			if (ptr->ch == cmp) {
+				if (*(++txt) == '\0') {
+					ptr->value = code;
+					return;
+				}
+				if (ptr->child != 0)
+					ptr = ptr->child;
+				else
+					break;
+			} else {
+				if ((ptr->sibling = typeCalloc(struct tries,1)) == 0) {
+					out_of_memory = TRUE;
+					return;
+				}
+
+				savedptr = ptr = ptr->sibling;
+				SET_TRY(ptr,txt);
+				ptr->value = 0;
+
+				break;
+			}
+		} /* end for (;;) */
+	} else {   /* (*tree) == 0 :: First sequence to be added */
+		savedptr = ptr = (*tree) = typeCalloc(struct tries,1);
+
+		if (ptr == 0) {
+			out_of_memory = TRUE;
+			return;
+		}
+
+		SET_TRY(ptr,txt);
+		ptr->value = 0;
+	}
+
+	    /* at this point, we are adding to the try.  ptr->child == 0 */
+
+	while (*txt) {
+		ptr->child = typeCalloc(struct tries,1);
+
+		ptr = ptr->child;
+
+		if (ptr == 0) {
+			out_of_memory = TRUE;
+
+			while ((ptr = savedptr) != 0) {
+				savedptr = ptr->child;
+				free(ptr);
+			}
+
+			return;
+		}
+
+		SET_TRY(ptr,txt);
+		ptr->value = 0;
+	}
+
+	ptr->value = code;
+	return;
+}
+
+/*
+ * Expand a keycode into the string that it corresponds to, returning null if
+ * no match was found, otherwise allocating a string of the result.
+ */
+char *_nc_expand_try(struct tries *tree, unsigned short code, size_t len)
+{
+	struct tries *ptr = tree;
+	char *result = 0;
+
+	if (code != 0) {
+		while (ptr != 0) {
+			if ((result = _nc_expand_try(ptr->child, code, len + 1)) != 0) {
+				break;
+			}
+			if (ptr->value == code) {
+				result = typeCalloc(char, len+2);
+				break;
+			}
+			ptr = ptr->sibling;
+		}
+	}
+	if (result != 0) {
+		if ((result[len] = ptr->ch) == 0)
+			*((unsigned char *)(result+len)) = 128;
+#ifdef TRACE
+		if (len == 0)
+			_tracef("expand_key %s %s", _trace_key(code), _nc_visbuf(result));
+#endif
+	}
+	return result;
+}
+
+/*
+ * Remove a code from the specified tree, freeing the unused nodes.  Returns
+ * true if the code was found/removed.
+ */
+int _nc_remove_key(struct tries **tree, unsigned short code)
+{
+	if (code == 0)
+		return FALSE;
+		
+	while (*tree != 0) {
+		if (_nc_remove_key(&(*tree)->child, code)) {
+			return TRUE;
+		}
+		if ((*tree)->value == code) {
+			if((*tree)->child) {
+				/* don't cut the whole sub-tree */
+				(*tree)->value = 0;
+			} else {
+				struct tries *to_free = *tree;
+				*tree = (*tree)->sibling;
+				free(to_free);
+			}
+			return TRUE;
+		}
+		tree = &(*tree)->sibling;
+	}
+	return FALSE;
+}