added POSIX regex to expr
[unix-history] / bin / cp / path.c
CommitLineData
15637ed4
RG
1/*-
2 * Copyright (c) 1991 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static char sccsid[] = "@(#)path.c 5.1 (Berkeley) 4/3/91";
36#endif /* not lint */
37
38#include <sys/param.h>
39#include <stdio.h>
40#include <string.h>
41#include "cp.h"
42
43/*
44 * These functions manipulate paths in PATH_T structures.
45 *
46 * They eliminate multiple slashes in paths when they notice them,
47 * and keep the path non-slash terminated.
48 *
49 * Both path_set() and path_append() return 0 if the requested name
50 * would be too long.
51 */
52
53#define STRIP_TRAILING_SLASH(p) { \
54 while ((p)->p_end > (p)->p_path && (p)->p_end[-1] == '/') \
55 *--(p)->p_end = 0; \
56}
57
58/*
59 * Move specified string into path. Convert "" to "." to handle BSD
60 * semantics for a null path. Strip trailing slashes.
61 */
62path_set(p, string)
63 register PATH_T *p;
64 char *string;
65{
66 if (strlen(string) > MAXPATHLEN) {
67 (void)fprintf(stderr,
68 "%s: %s: name too long.\n", progname, string);
69 return(0);
70 }
71
72 (void)strcpy(p->p_path, string);
73 p->p_end = p->p_path + strlen(p->p_path);
74
75 if (p->p_path == p->p_end) {
76 *p->p_end++ = '.';
77 *p->p_end = 0;
78 }
79
80 STRIP_TRAILING_SLASH(p);
81 return(1);
82}
83
84/*
85 * Append specified string to path, inserting '/' if necessary. Return a
86 * pointer to the old end of path for restoration.
87 */
88char *
89path_append(p, name, len)
90 register PATH_T *p;
91 char *name;
92 int len;
93{
94 char *old;
95
96 old = p->p_end;
97 if (len == -1)
98 len = strlen(name);
99
100 /* The "+ 1" accounts for the '/' between old path and name. */
101 if ((len + p->p_end - p->p_path + 1) > MAXPATHLEN) {
102 (void)fprintf(stderr,
103 "%s: %s/%s: name too long.\n", progname, p->p_path, name);
104 return(0);
105 }
106
107 /*
108 * This code should always be executed, since paths shouldn't
109 * end in '/'.
110 */
111 if (p->p_end[-1] != '/') {
112 *p->p_end++ = '/';
113 *p->p_end = 0;
114 }
115
116 (void)strncat(p->p_end, name, len);
117 p->p_end += len;
118 *p->p_end = 0;
119
120 STRIP_TRAILING_SLASH(p);
121 return(old);
122}
123
124/*
125 * Restore path to previous value. (As returned by path_append.)
126 */
127void
128path_restore(p, old)
129 PATH_T *p;
130 char *old;
131{
132 p->p_end = old;
133 *p->p_end = 0;
134}
135
136/*
137 * Return basename of path.
138 */
139char *
140path_basename(p)
141 PATH_T *p;
142{
143 char *basename;
144
145 basename = rindex(p->p_path, '/');
146 return(basename ? basename + 1 : p->p_path);
147}