1/****************************************************************************
2 * Copyright (c) 1998-2007,2008 Free Software Foundation, Inc.              *
3 *                                                                          *
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11 *                                                                          *
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14 *                                                                          *
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22 *                                                                          *
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28
29/****************************************************************************
30 *  Author: Thomas E. Dickey <dickey@clark.net> 1997                        *
31 ****************************************************************************/
32
33/*
34**	tries.c
35**
36**	Functions to manage the tree of partial-completions for keycodes.
37**
38*/
39
40#include <curses.priv.h>
41
42MODULE_ID("$Id: tries.c,v 1.27 2008/08/16 19:22:55 tom Exp $")
43
44/*
45 * Expand a keycode into the string that it corresponds to, returning null if
46 * no match was found, otherwise allocating a string of the result.
47 */
48NCURSES_EXPORT(char *)
49_nc_expand_try(TRIES * tree, unsigned code, int *count, size_t len)
50{
51    TRIES *ptr = tree;
52    char *result = 0;
53
54    if (code != 0) {
55	while (ptr != 0) {
56	    if ((result = _nc_expand_try(ptr->child, code, count, len + 1))
57		!= 0) {
58		break;
59	    }
60	    if (ptr->value == code) {
61		*count -= 1;
62		if (*count == -1) {
63		    result = typeCalloc(char, len + 2);
64		    break;
65		}
66	    }
67	    ptr = ptr->sibling;
68	}
69    }
70    if (result != 0) {
71	if (ptr != 0 && (result[len] = (char) ptr->ch) == 0)
72	    *((unsigned char *) (result + len)) = 128;
73#ifdef TRACE
74	if (len == 0 && USE_TRACEF(TRACE_MAXIMUM)) {
75	    _tracef("expand_key %s %s", _nc_tracechar(SP, code), _nc_visbuf(result));
76	    _nc_unlock_global(tracef);
77	}
78#endif
79    }
80    return result;
81}
82
83/*
84 * Remove a code from the specified tree, freeing the unused nodes.  Returns
85 * true if the code was found/removed.
86 */
87NCURSES_EXPORT(int)
88_nc_remove_key(TRIES ** tree, unsigned code)
89{
90    T((T_CALLED("_nc_remove_key(%p,%d)"), tree, code));
91
92    if (code == 0)
93	returnCode(FALSE);
94
95    while (*tree != 0) {
96	if (_nc_remove_key(&(*tree)->child, code)) {
97	    returnCode(TRUE);
98	}
99	if ((*tree)->value == code) {
100	    if ((*tree)->child) {
101		/* don't cut the whole sub-tree */
102		(*tree)->value = 0;
103	    } else {
104		TRIES *to_free = *tree;
105		*tree = (*tree)->sibling;
106		free(to_free);
107	    }
108	    returnCode(TRUE);
109	}
110	tree = &(*tree)->sibling;
111    }
112    returnCode(FALSE);
113}
114
115/*
116 * Remove a string from the specified tree, freeing the unused nodes.  Returns
117 * true if the string was found/removed.
118 */
119NCURSES_EXPORT(int)
120_nc_remove_string(TRIES ** tree, const char *string)
121{
122    T((T_CALLED("_nc_remove_string(%p,%s)"), tree, _nc_visbuf(string)));
123
124    if (string == 0 || *string == 0)
125	returnCode(FALSE);
126
127    while (*tree != 0) {
128	if (UChar((*tree)->ch) == UChar(*string)) {
129	    if (string[1] != 0)
130		returnCode(_nc_remove_string(&(*tree)->child, string + 1));
131	    if ((*tree)->child == 0) {
132		TRIES *to_free = *tree;
133		*tree = (*tree)->sibling;
134		free(to_free);
135		returnCode(TRUE);
136	    } else {
137		returnCode(FALSE);
138	    }
139	}
140	tree = &(*tree)->sibling;
141    }
142    returnCode(FALSE);
143}
144