1/****************************************************************************
2 * Copyright (c) 1998-2009,2010 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 1.30 2010/08/28 21:08:23 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",
76		    _nc_tracechar(CURRENT_SCREEN, (int) code),
77		    _nc_visbuf(result));
78	    _nc_unlock_global(tracef);
79	}
80#endif
81    }
82    return result;
83}
84
85/*
86 * Remove a code from the specified tree, freeing the unused nodes.  Returns
87 * true if the code was found/removed.
88 */
89NCURSES_EXPORT(int)
90_nc_remove_key(TRIES ** tree, unsigned code)
91{
92    T((T_CALLED("_nc_remove_key(%p,%d)"), (void *) tree, code));
93
94    if (code == 0)
95	returnCode(FALSE);
96
97    while (*tree != 0) {
98	if (_nc_remove_key(&(*tree)->child, code)) {
99	    returnCode(TRUE);
100	}
101	if ((*tree)->value == code) {
102	    if ((*tree)->child) {
103		/* don't cut the whole sub-tree */
104		(*tree)->value = 0;
105	    } else {
106		TRIES *to_free = *tree;
107		*tree = (*tree)->sibling;
108		free(to_free);
109	    }
110	    returnCode(TRUE);
111	}
112	tree = &(*tree)->sibling;
113    }
114    returnCode(FALSE);
115}
116
117/*
118 * Remove a string from the specified tree, freeing the unused nodes.  Returns
119 * true if the string was found/removed.
120 */
121NCURSES_EXPORT(int)
122_nc_remove_string(TRIES ** tree, const char *string)
123{
124    T((T_CALLED("_nc_remove_string(%p,%s)"), (void *) tree, _nc_visbuf(string)));
125
126    if (string == 0 || *string == 0)
127	returnCode(FALSE);
128
129    while (*tree != 0) {
130	if (UChar((*tree)->ch) == UChar(*string)) {
131	    if (string[1] != 0)
132		returnCode(_nc_remove_string(&(*tree)->child, string + 1));
133	    if ((*tree)->child == 0) {
134		TRIES *to_free = *tree;
135		*tree = (*tree)->sibling;
136		free(to_free);
137		returnCode(TRUE);
138	    } else {
139		returnCode(FALSE);
140	    }
141	}
142	tree = &(*tree)->sibling;
143    }
144    returnCode(FALSE);
145}
146