1/****************************************************************************
2 * Copyright (c) 2000-2007,2012 Free Software Foundation, Inc.              *
3 *                                                                          *
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5 * copy of this software and associated documentation files (the            *
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9 * copies of the Software, and to permit persons to whom the Software is    *
10 * furnished to do so, subject to the following conditions:                 *
11 *                                                                          *
12 * The above copyright notice and this permission notice shall be included  *
13 * in all copies or substantial portions of the Software.                   *
14 *                                                                          *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
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22 *                                                                          *
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26 * authorization.                                                           *
27 ****************************************************************************/
28
29/****************************************************************************
30 *  Author: Thomas E. Dickey                                                *
31 ****************************************************************************/
32
33/*
34**	lib_mvcur.c
35**/
36
37#include <curses.priv.h>
38
39MODULE_ID("$Id: strings.c,v 1.8 2012/02/22 22:34:31 tom Exp $")
40
41/****************************************************************************
42 * Useful string functions (especially for mvcur)
43 ****************************************************************************/
44
45#if !HAVE_STRSTR
46NCURSES_EXPORT(char *)
47_nc_strstr(const char *haystack, const char *needle)
48{
49    size_t len1 = strlen(haystack);
50    size_t len2 = strlen(needle);
51    char *result = 0;
52
53    while ((len1 != 0) && (len1-- >= len2)) {
54	if (!strncmp(haystack, needle, len2)) {
55	    result = (char *) haystack;
56	    break;
57	}
58	haystack++;
59    }
60    return result;
61}
62#endif
63
64/*
65 * Initialize the descriptor so we can append to it.  Note that 'src' may
66 * be a null pointer (see _nc_str_null), so the corresponding strcat and
67 * strcpy calls have to allow for this.
68 */
69NCURSES_EXPORT(string_desc *)
70_nc_str_init(string_desc * dst, char *src, size_t len)
71{
72    if (dst != 0) {
73	dst->s_head = src;
74	dst->s_tail = src;
75	dst->s_size = len - 1;
76	dst->s_init = dst->s_size;
77	if (src != 0)
78	    *src = 0;
79    }
80    return dst;
81}
82
83/*
84 * Initialize the descriptor for only tracking the amount of memory used.
85 */
86NCURSES_EXPORT(string_desc *)
87_nc_str_null(string_desc * dst, size_t len)
88{
89    return _nc_str_init(dst, 0, len);
90}
91
92/*
93 * Copy a descriptor
94 */
95NCURSES_EXPORT(string_desc *)
96_nc_str_copy(string_desc * dst, string_desc * src)
97{
98    *dst = *src;
99    return dst;
100}
101
102/*
103 * Replaces strcat into a fixed buffer, returning false on failure.
104 */
105NCURSES_EXPORT(bool)
106_nc_safe_strcat(string_desc * dst, const char *src)
107{
108    if (src != 0) {
109	size_t len = strlen(src);
110
111	if (len < dst->s_size) {
112	    if (dst->s_tail != 0) {
113		_nc_STRCPY(dst->s_tail, src, dst->s_size);
114		dst->s_tail += len;
115	    }
116	    dst->s_size -= len;
117	    return TRUE;
118	}
119    }
120    return FALSE;
121}
122
123/*
124 * Replaces strcpy into a fixed buffer, returning false on failure.
125 */
126NCURSES_EXPORT(bool)
127_nc_safe_strcpy(string_desc * dst, const char *src)
128{
129    if (src != 0) {
130	size_t len = strlen(src);
131
132	if (len < dst->s_size) {
133	    if (dst->s_head != 0) {
134		_nc_STRCPY(dst->s_head, src, dst->s_size);
135		dst->s_tail = dst->s_head + len;
136	    }
137	    dst->s_size = dst->s_init - len;
138	    return TRUE;
139	}
140    }
141    return FALSE;
142}
143